usb host: Faraday USB2.0 FUSBH200-HCD driver

FUSBH200-HCD is an USB2.0 hcd for Faraday FUSBH200.
FUSBH200 is an ehci-like controller with some differences.
First, register layout of FUSBH200 is incompatible with EHCI.
Furthermore, FUSBH200 is lack of siTDs which means iTDs
are used for both HS and FS ISO transfer.

Signed-off-by: Yuan-Hsin Chen <yhchen@faraday-tech.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/Makefile

@@ -25,6 +25,7 @@ obj-$(CONFIG_USB_HWA_HCD)	+= host/
 obj-$(CONFIG_USB_ISP1760_HCD)	+= host/
 obj-$(CONFIG_USB_IMX21_HCD)	+= host/
 obj-$(CONFIG_USB_FSL_MPH_DR_OF)	+= host/
+obj-$(CONFIG_USB_FUSBH200_HCD)	+= host/
 
 obj-$(CONFIG_USB_C67X00_HCD)	+= c67x00/
 

drivers/usb/host/Kconfig

@@ -345,6 +345,17 @@ config USB_ISP1362_HCD
 	  To compile this driver as a module, choose M here: the
 	  module will be called isp1362-hcd.
 
+config USB_FUSBH200_HCD
+	tristate "FUSBH200 HCD support"
+	depends on USB
+	default N
+	---help---
+	Faraday FUSBH200 is designed to meet USB2.0 EHCI specification
+	with minor modification.
+
+	To compile this driver as a module, choose M here: the
+	module will be called fusbh200-hcd.
+
 config USB_OHCI_HCD
 	tristate "OHCI HCD support"
 	depends on USB_ARCH_HAS_OHCI

drivers/usb/host/Makefile

@@ -52,3 +52,4 @@ obj-$(CONFIG_USB_FSL_MPH_DR_OF)	+= fsl-mph-dr-of.o
 obj-$(CONFIG_USB_OCTEON2_COMMON) += octeon2-common.o
 obj-$(CONFIG_USB_HCD_BCMA)	+= bcma-hcd.o
 obj-$(CONFIG_USB_HCD_SSB)	+= ssb-hcd.o
+obj-$(CONFIG_USB_FUSBH200_HCD)	+= fusbh200-hcd.o

drivers/usb/host/fusbh200-hcd.c

@@ -0,0 +1,5975 @@
+/*
+ * Faraday FUSBH200 EHCI-like driver
+ *
+ * Copyright (c) 2013 Faraday Technology Corporation
+ *
+ * Author: Yuan-Hsin Chen <yhchen@faraday-tech.com>
+ * 	   Feng-Hsin Chiang <john453@faraday-tech.com>
+ * 	   Po-Yu Chuang <ratbert.chuang@gmail.com>
+ *
+ * Most of code borrowed from the Linux-3.7 EHCI driver
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/dmapool.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/ioport.h>
+#include <linux/sched.h>
+#include <linux/vmalloc.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/hrtimer.h>
+#include <linux/list.h>
+#include <linux/interrupt.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+#include <linux/moduleparam.h>
+#include <linux/dma-mapping.h>
+#include <linux/debugfs.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/platform_device.h>
+
+#include <asm/byteorder.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/unaligned.h>
+
+/*-------------------------------------------------------------------------*/
+#define DRIVER_AUTHOR "Yuan-Hsin Chen"
+#define DRIVER_DESC "FUSBH200 Host Controller (EHCI) Driver"
+
+static const char	hcd_name [] = "fusbh200_hcd";
+
+#undef VERBOSE_DEBUG
+#undef FUSBH200_URB_TRACE
+
+#ifdef DEBUG
+#define FUSBH200_STATS
+#endif
+
+/* magic numbers that can affect system performance */
+#define	FUSBH200_TUNE_CERR		3	/* 0-3 qtd retries; 0 == don't stop */
+#define	FUSBH200_TUNE_RL_HS		4	/* nak throttle; see 4.9 */
+#define	FUSBH200_TUNE_RL_TT		0
+#define	FUSBH200_TUNE_MULT_HS	1	/* 1-3 transactions/uframe; 4.10.3 */
+#define	FUSBH200_TUNE_MULT_TT	1
+/*
+ * Some drivers think it's safe to schedule isochronous transfers more than
+ * 256 ms into the future (partly as a result of an old bug in the scheduling
+ * code).  In an attempt to avoid trouble, we will use a minimum scheduling
+ * length of 512 frames instead of 256.
+ */
+#define	FUSBH200_TUNE_FLS		1	/* (medium) 512-frame schedule */
+
+/* Initial IRQ latency:  faster than hw default */
+static int log2_irq_thresh = 0;		// 0 to 6
+module_param (log2_irq_thresh, int, S_IRUGO);
+MODULE_PARM_DESC (log2_irq_thresh, "log2 IRQ latency, 1-64 microframes");
+
+/* initial park setting:  slower than hw default */
+static unsigned park = 0;
+module_param (park, uint, S_IRUGO);
+MODULE_PARM_DESC (park, "park setting; 1-3 back-to-back async packets");
+
+/* for link power management(LPM) feature */
+static unsigned int hird;
+module_param(hird, int, S_IRUGO);
+MODULE_PARM_DESC(hird, "host initiated resume duration, +1 for each 75us");
+
+#define	INTR_MASK (STS_IAA | STS_FATAL | STS_PCD | STS_ERR | STS_INT)
+
+#include "fusbh200.h"
+
+/*-------------------------------------------------------------------------*/
+
+#define fusbh200_dbg(fusbh200, fmt, args...) \
+	dev_dbg (fusbh200_to_hcd(fusbh200)->self.controller , fmt , ## args )
+#define fusbh200_err(fusbh200, fmt, args...) \
+	dev_err (fusbh200_to_hcd(fusbh200)->self.controller , fmt , ## args )
+#define fusbh200_info(fusbh200, fmt, args...) \
+	dev_info (fusbh200_to_hcd(fusbh200)->self.controller , fmt , ## args )
+#define fusbh200_warn(fusbh200, fmt, args...) \
+	dev_warn (fusbh200_to_hcd(fusbh200)->self.controller , fmt , ## args )
+
+#ifdef VERBOSE_DEBUG
+#	define fusbh200_vdbg fusbh200_dbg
+#else
+	static inline void fusbh200_vdbg(struct fusbh200_hcd *fusbh200, ...) {}
+#endif
+
+#ifdef	DEBUG
+
+/* check the values in the HCSPARAMS register
+ * (host controller _Structural_ parameters)
+ * see EHCI spec, Table 2-4 for each value
+ */
+static void dbg_hcs_params (struct fusbh200_hcd *fusbh200, char *label)
+{
+	u32	params = fusbh200_readl(fusbh200, &fusbh200->caps->hcs_params);
+
+	fusbh200_dbg (fusbh200,
+		"%s hcs_params 0x%x ports=%d\n",
+		label, params,
+		HCS_N_PORTS (params)
+		);
+}
+#else
+
+static inline void dbg_hcs_params (struct fusbh200_hcd *fusbh200, char *label) {}
+
+#endif
+
+#ifdef	DEBUG
+
+/* check the values in the HCCPARAMS register
+ * (host controller _Capability_ parameters)
+ * see EHCI Spec, Table 2-5 for each value
+ * */
+static void dbg_hcc_params (struct fusbh200_hcd *fusbh200, char *label)
+{
+	u32	params = fusbh200_readl(fusbh200, &fusbh200->caps->hcc_params);
+
+	fusbh200_dbg (fusbh200,
+		"%s hcc_params %04x uframes %s%s\n",
+		label,
+		params,
+		HCC_PGM_FRAMELISTLEN(params) ? "256/512/1024" : "1024",
+		HCC_CANPARK(params) ? " park" : "");
+}
+#else
+
+static inline void dbg_hcc_params (struct fusbh200_hcd *fusbh200, char *label) {}
+
+#endif
+
+#ifdef	DEBUG
+
+static void __maybe_unused
+dbg_qtd (const char *label, struct fusbh200_hcd *fusbh200, struct fusbh200_qtd *qtd)
+{
+	fusbh200_dbg(fusbh200, "%s td %p n%08x %08x t%08x p0=%08x\n", label, qtd,
+		hc32_to_cpup(fusbh200, &qtd->hw_next),
+		hc32_to_cpup(fusbh200, &qtd->hw_alt_next),
+		hc32_to_cpup(fusbh200, &qtd->hw_token),
+		hc32_to_cpup(fusbh200, &qtd->hw_buf [0]));
+	if (qtd->hw_buf [1])
+		fusbh200_dbg(fusbh200, "  p1=%08x p2=%08x p3=%08x p4=%08x\n",
+			hc32_to_cpup(fusbh200, &qtd->hw_buf[1]),
+			hc32_to_cpup(fusbh200, &qtd->hw_buf[2]),
+			hc32_to_cpup(fusbh200, &qtd->hw_buf[3]),
+			hc32_to_cpup(fusbh200, &qtd->hw_buf[4]));
+}
+
+static void __maybe_unused
+dbg_qh (const char *label, struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{
+	struct fusbh200_qh_hw *hw = qh->hw;
+
+	fusbh200_dbg (fusbh200, "%s qh %p n%08x info %x %x qtd %x\n", label,
+		qh, hw->hw_next, hw->hw_info1, hw->hw_info2, hw->hw_current);
+	dbg_qtd("overlay", fusbh200, (struct fusbh200_qtd *) &hw->hw_qtd_next);
+}
+
+static void __maybe_unused
+dbg_itd (const char *label, struct fusbh200_hcd *fusbh200, struct fusbh200_itd *itd)
+{
+	fusbh200_dbg (fusbh200, "%s [%d] itd %p, next %08x, urb %p\n",
+		label, itd->frame, itd, hc32_to_cpu(fusbh200, itd->hw_next),
+		itd->urb);
+	fusbh200_dbg (fusbh200,
+		"  trans: %08x %08x %08x %08x %08x %08x %08x %08x\n",
+		hc32_to_cpu(fusbh200, itd->hw_transaction[0]),
+		hc32_to_cpu(fusbh200, itd->hw_transaction[1]),
+		hc32_to_cpu(fusbh200, itd->hw_transaction[2]),
+		hc32_to_cpu(fusbh200, itd->hw_transaction[3]),
+		hc32_to_cpu(fusbh200, itd->hw_transaction[4]),
+		hc32_to_cpu(fusbh200, itd->hw_transaction[5]),
+		hc32_to_cpu(fusbh200, itd->hw_transaction[6]),
+		hc32_to_cpu(fusbh200, itd->hw_transaction[7]));
+	fusbh200_dbg (fusbh200,
+		"  buf:   %08x %08x %08x %08x %08x %08x %08x\n",
+		hc32_to_cpu(fusbh200, itd->hw_bufp[0]),
+		hc32_to_cpu(fusbh200, itd->hw_bufp[1]),
+		hc32_to_cpu(fusbh200, itd->hw_bufp[2]),
+		hc32_to_cpu(fusbh200, itd->hw_bufp[3]),
+		hc32_to_cpu(fusbh200, itd->hw_bufp[4]),
+		hc32_to_cpu(fusbh200, itd->hw_bufp[5]),
+		hc32_to_cpu(fusbh200, itd->hw_bufp[6]));
+	fusbh200_dbg (fusbh200, "  index: %d %d %d %d %d %d %d %d\n",
+		itd->index[0], itd->index[1], itd->index[2],
+		itd->index[3], itd->index[4], itd->index[5],
+		itd->index[6], itd->index[7]);
+}
+
+static int __maybe_unused
+dbg_status_buf (char *buf, unsigned len, const char *label, u32 status)
+{
+	return scnprintf (buf, len,
+		"%s%sstatus %04x%s%s%s%s%s%s%s%s%s%s",
+		label, label [0] ? " " : "", status,
+		(status & STS_ASS) ? " Async" : "",
+		(status & STS_PSS) ? " Periodic" : "",
+		(status & STS_RECL) ? " Recl" : "",
+		(status & STS_HALT) ? " Halt" : "",
+		(status & STS_IAA) ? " IAA" : "",
+		(status & STS_FATAL) ? " FATAL" : "",
+		(status & STS_FLR) ? " FLR" : "",
+		(status & STS_PCD) ? " PCD" : "",
+		(status & STS_ERR) ? " ERR" : "",
+		(status & STS_INT) ? " INT" : ""
+		);
+}
+
+static int __maybe_unused
+dbg_intr_buf (char *buf, unsigned len, const char *label, u32 enable)
+{
+	return scnprintf (buf, len,
+		"%s%sintrenable %02x%s%s%s%s%s%s",
+		label, label [0] ? " " : "", enable,
+		(enable & STS_IAA) ? " IAA" : "",
+		(enable & STS_FATAL) ? " FATAL" : "",
+		(enable & STS_FLR) ? " FLR" : "",
+		(enable & STS_PCD) ? " PCD" : "",
+		(enable & STS_ERR) ? " ERR" : "",
+		(enable & STS_INT) ? " INT" : ""
+		);
+}
+
+static const char *const fls_strings [] =
+    { "1024", "512", "256", "??" };
+
+static int
+dbg_command_buf (char *buf, unsigned len, const char *label, u32 command)
+{
+	return scnprintf (buf, len,
+		"%s%scommand %07x %s=%d ithresh=%d%s%s%s "
+		"period=%s%s %s",
+		label, label [0] ? " " : "", command,
+		(command & CMD_PARK) ? " park" : "(park)",
+		CMD_PARK_CNT (command),
+		(command >> 16) & 0x3f,
+		(command & CMD_IAAD) ? " IAAD" : "",
+		(command & CMD_ASE) ? " Async" : "",
+		(command & CMD_PSE) ? " Periodic" : "",
+		fls_strings [(command >> 2) & 0x3],
+		(command & CMD_RESET) ? " Reset" : "",
+		(command & CMD_RUN) ? "RUN" : "HALT"
+		);
+}
+
+static int
+dbg_port_buf (char *buf, unsigned len, const char *label, int port, u32 status)
+{
+	char	*sig;
+
+	/* signaling state */
+	switch (status & (3 << 10)) {
+	case 0 << 10: sig = "se0"; break;
+	case 1 << 10: sig = "k"; break;		/* low speed */
+	case 2 << 10: sig = "j"; break;
+	default: sig = "?"; break;
+	}
+
+	return scnprintf (buf, len,
+		"%s%sport:%d status %06x %d "
+		"sig=%s%s%s%s%s%s%s%s",
+		label, label [0] ? " " : "", port, status,
+		status>>25,/*device address */
+		sig,
+		(status & PORT_RESET) ? " RESET" : "",
+		(status & PORT_SUSPEND) ? " SUSPEND" : "",
+		(status & PORT_RESUME) ? " RESUME" : "",
+		(status & PORT_PEC) ? " PEC" : "",
+		(status & PORT_PE) ? " PE" : "",
+		(status & PORT_CSC) ? " CSC" : "",
+		(status & PORT_CONNECT) ? " CONNECT" : "");
+}
+
+#else
+static inline void __maybe_unused
+dbg_qh (char *label, struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{}
+
+static inline int __maybe_unused
+dbg_status_buf (char *buf, unsigned len, const char *label, u32 status)
+{ return 0; }
+
+static inline int __maybe_unused
+dbg_command_buf (char *buf, unsigned len, const char *label, u32 command)
+{ return 0; }
+
+static inline int __maybe_unused
+dbg_intr_buf (char *buf, unsigned len, const char *label, u32 enable)
+{ return 0; }
+
+static inline int __maybe_unused
+dbg_port_buf (char *buf, unsigned len, const char *label, int port, u32 status)
+{ return 0; }
+
+#endif	/* DEBUG */
+
+/* functions have the "wrong" filename when they're output... */
+#define dbg_status(fusbh200, label, status) { \
+	char _buf [80]; \
+	dbg_status_buf (_buf, sizeof _buf, label, status); \
+	fusbh200_dbg (fusbh200, "%s\n", _buf); \
+}
+
+#define dbg_cmd(fusbh200, label, command) { \
+	char _buf [80]; \
+	dbg_command_buf (_buf, sizeof _buf, label, command); \
+	fusbh200_dbg (fusbh200, "%s\n", _buf); \
+}
+
+#define dbg_port(fusbh200, label, port, status) { \
+	char _buf [80]; \
+	dbg_port_buf (_buf, sizeof _buf, label, port, status); \
+	fusbh200_dbg (fusbh200, "%s\n", _buf); \
+}
+
+/*-------------------------------------------------------------------------*/
+
+#ifdef STUB_DEBUG_FILES
+
+static inline void create_debug_files (struct fusbh200_hcd *bus) { }
+static inline void remove_debug_files (struct fusbh200_hcd *bus) { }
+
+#else
+
+/* troubleshooting help: expose state in debugfs */
+
+static int debug_async_open(struct inode *, struct file *);
+static int debug_periodic_open(struct inode *, struct file *);
+static int debug_registers_open(struct inode *, struct file *);
+static int debug_async_open(struct inode *, struct file *);
+
+static ssize_t debug_output(struct file*, char __user*, size_t, loff_t*);
+static int debug_close(struct inode *, struct file *);
+
+static const struct file_operations debug_async_fops = {
+	.owner		= THIS_MODULE,
+	.open		= debug_async_open,
+	.read		= debug_output,
+	.release	= debug_close,
+	.llseek		= default_llseek,
+};
+static const struct file_operations debug_periodic_fops = {
+	.owner		= THIS_MODULE,
+	.open		= debug_periodic_open,
+	.read		= debug_output,
+	.release	= debug_close,
+	.llseek		= default_llseek,
+};
+static const struct file_operations debug_registers_fops = {
+	.owner		= THIS_MODULE,
+	.open		= debug_registers_open,
+	.read		= debug_output,
+	.release	= debug_close,
+	.llseek		= default_llseek,
+};
+
+static struct dentry *fusbh200_debug_root;
+
+struct debug_buffer {
+	ssize_t (*fill_func)(struct debug_buffer *);	/* fill method */
+	struct usb_bus *bus;
+	struct mutex mutex;	/* protect filling of buffer */
+	size_t count;		/* number of characters filled into buffer */
+	char *output_buf;
+	size_t alloc_size;
+};
+
+#define speed_char(info1) ({ char tmp; \
+		switch (info1 & (3 << 12)) { \
+		case QH_FULL_SPEED: tmp = 'f'; break; \
+		case QH_LOW_SPEED:  tmp = 'l'; break; \
+		case QH_HIGH_SPEED: tmp = 'h'; break; \
+		default: tmp = '?'; break; \
+		}; tmp; })
+
+static inline char token_mark(struct fusbh200_hcd *fusbh200, __hc32 token)
+{
+	__u32 v = hc32_to_cpu(fusbh200, token);
+
+	if (v & QTD_STS_ACTIVE)
+		return '*';
+	if (v & QTD_STS_HALT)
+		return '-';
+	if (!IS_SHORT_READ (v))
+		return ' ';
+	/* tries to advance through hw_alt_next */
+	return '/';
+}
+
+static void qh_lines (
+	struct fusbh200_hcd *fusbh200,
+	struct fusbh200_qh *qh,
+	char **nextp,
+	unsigned *sizep
+)
+{
+	u32			scratch;
+	u32			hw_curr;
+	struct list_head	*entry;
+	struct fusbh200_qtd		*td;
+	unsigned		temp;
+	unsigned		size = *sizep;
+	char			*next = *nextp;
+	char			mark;
+	__le32			list_end = FUSBH200_LIST_END(fusbh200);
+	struct fusbh200_qh_hw	*hw = qh->hw;
+
+	if (hw->hw_qtd_next == list_end)	/* NEC does this */
+		mark = '@';
+	else
+		mark = token_mark(fusbh200, hw->hw_token);
+	if (mark == '/') {	/* qh_alt_next controls qh advance? */
+		if ((hw->hw_alt_next & QTD_MASK(fusbh200))
+				== fusbh200->async->hw->hw_alt_next)
+			mark = '#';	/* blocked */
+		else if (hw->hw_alt_next == list_end)
+			mark = '.';	/* use hw_qtd_next */
+		/* else alt_next points to some other qtd */
+	}
+	scratch = hc32_to_cpup(fusbh200, &hw->hw_info1);
+	hw_curr = (mark == '*') ? hc32_to_cpup(fusbh200, &hw->hw_current) : 0;
+	temp = scnprintf (next, size,
+			"qh/%p dev%d %cs ep%d %08x %08x (%08x%c %s nak%d)",
+			qh, scratch & 0x007f,
+			speed_char (scratch),
+			(scratch >> 8) & 0x000f,
+			scratch, hc32_to_cpup(fusbh200, &hw->hw_info2),
+			hc32_to_cpup(fusbh200, &hw->hw_token), mark,
+			(cpu_to_hc32(fusbh200, QTD_TOGGLE) & hw->hw_token)
+				? "data1" : "data0",
+			(hc32_to_cpup(fusbh200, &hw->hw_alt_next) >> 1) & 0x0f);
+	size -= temp;
+	next += temp;
+
+	/* hc may be modifying the list as we read it ... */
+	list_for_each (entry, &qh->qtd_list) {
+		td = list_entry (entry, struct fusbh200_qtd, qtd_list);
+		scratch = hc32_to_cpup(fusbh200, &td->hw_token);
+		mark = ' ';
+		if (hw_curr == td->qtd_dma)
+			mark = '*';
+		else if (hw->hw_qtd_next == cpu_to_hc32(fusbh200, td->qtd_dma))
+			mark = '+';
+		else if (QTD_LENGTH (scratch)) {
+			if (td->hw_alt_next == fusbh200->async->hw->hw_alt_next)
+				mark = '#';
+			else if (td->hw_alt_next != list_end)
+				mark = '/';
+		}
+		temp = snprintf (next, size,
+				"\n\t%p%c%s len=%d %08x urb %p",
+				td, mark, ({ char *tmp;
+				 switch ((scratch>>8)&0x03) {
+				 case 0: tmp = "out"; break;
+				 case 1: tmp = "in"; break;
+				 case 2: tmp = "setup"; break;
+				 default: tmp = "?"; break;
+				 } tmp;}),
+				(scratch >> 16) & 0x7fff,
+				scratch,
+				td->urb);
+		if (size < temp)
+			temp = size;
+		size -= temp;
+		next += temp;
+		if (temp == size)
+			goto done;
+	}
+
+	temp = snprintf (next, size, "\n");
+	if (size < temp)
+		temp = size;
+	size -= temp;
+	next += temp;
+
+done:
+	*sizep = size;
+	*nextp = next;
+}
+
+static ssize_t fill_async_buffer(struct debug_buffer *buf)
+{
+	struct usb_hcd		*hcd;
+	struct fusbh200_hcd	*fusbh200;
+	unsigned long		flags;
+	unsigned		temp, size;
+	char			*next;
+	struct fusbh200_qh		*qh;
+
+	hcd = bus_to_hcd(buf->bus);
+	fusbh200 = hcd_to_fusbh200 (hcd);
+	next = buf->output_buf;
+	size = buf->alloc_size;
+
+	*next = 0;
+
+	/* dumps a snapshot of the async schedule.
+	 * usually empty except for long-term bulk reads, or head.
+	 * one QH per line, and TDs we know about
+	 */
+	spin_lock_irqsave (&fusbh200->lock, flags);
+	for (qh = fusbh200->async->qh_next.qh; size > 0 && qh; qh = qh->qh_next.qh)
+		qh_lines (fusbh200, qh, &next, &size);
+	if (fusbh200->async_unlink && size > 0) {
+		temp = scnprintf(next, size, "\nunlink =\n");
+		size -= temp;
+		next += temp;
+
+		for (qh = fusbh200->async_unlink; size > 0 && qh;
+				qh = qh->unlink_next)
+			qh_lines (fusbh200, qh, &next, &size);
+	}
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+
+	return strlen(buf->output_buf);
+}
+
+#define DBG_SCHED_LIMIT 64
+static ssize_t fill_periodic_buffer(struct debug_buffer *buf)
+{
+	struct usb_hcd		*hcd;
+	struct fusbh200_hcd		*fusbh200;
+	unsigned long		flags;
+	union fusbh200_shadow	p, *seen;
+	unsigned		temp, size, seen_count;
+	char			*next;
+	unsigned		i;
+	__hc32			tag;
+
+	if (!(seen = kmalloc (DBG_SCHED_LIMIT * sizeof *seen, GFP_ATOMIC)))
+		return 0;
+	seen_count = 0;
+
+	hcd = bus_to_hcd(buf->bus);
+	fusbh200 = hcd_to_fusbh200 (hcd);
+	next = buf->output_buf;
+	size = buf->alloc_size;
+
+	temp = scnprintf (next, size, "size = %d\n", fusbh200->periodic_size);
+	size -= temp;
+	next += temp;
+
+	/* dump a snapshot of the periodic schedule.
+	 * iso changes, interrupt usually doesn't.
+	 */
+	spin_lock_irqsave (&fusbh200->lock, flags);
+	for (i = 0; i < fusbh200->periodic_size; i++) {
+		p = fusbh200->pshadow [i];
+		if (likely (!p.ptr))
+			continue;
+		tag = Q_NEXT_TYPE(fusbh200, fusbh200->periodic [i]);
+
+		temp = scnprintf (next, size, "%4d: ", i);
+		size -= temp;
+		next += temp;
+
+		do {
+			struct fusbh200_qh_hw *hw;
+
+			switch (hc32_to_cpu(fusbh200, tag)) {
+			case Q_TYPE_QH:
+				hw = p.qh->hw;
+				temp = scnprintf (next, size, " qh%d-%04x/%p",
+						p.qh->period,
+						hc32_to_cpup(fusbh200,
+							&hw->hw_info2)
+							/* uframe masks */
+							& (QH_CMASK | QH_SMASK),
+						p.qh);
+				size -= temp;
+				next += temp;
+				/* don't repeat what follows this qh */
+				for (temp = 0; temp < seen_count; temp++) {
+					if (seen [temp].ptr != p.ptr)
+						continue;
+					if (p.qh->qh_next.ptr) {
+						temp = scnprintf (next, size,
+							" ...");
+						size -= temp;
+						next += temp;
+					}
+					break;
+				}
+				/* show more info the first time around */
+				if (temp == seen_count) {
+					u32	scratch = hc32_to_cpup(fusbh200,
+							&hw->hw_info1);
+					struct fusbh200_qtd	*qtd;
+					char		*type = "";
+
+					/* count tds, get ep direction */
+					temp = 0;
+					list_for_each_entry (qtd,
+							&p.qh->qtd_list,
+							qtd_list) {
+						temp++;
+						switch (0x03 & (hc32_to_cpu(
+							fusbh200,
+							qtd->hw_token) >> 8)) {
+						case 0: type = "out"; continue;
+						case 1: type = "in"; continue;
+						}
+					}
+
+					temp = scnprintf (next, size,
+						" (%c%d ep%d%s "
+						"[%d/%d] q%d p%d)",
+						speed_char (scratch),
+						scratch & 0x007f,
+						(scratch >> 8) & 0x000f, type,
+						p.qh->usecs, p.qh->c_usecs,
+						temp,
+						0x7ff & (scratch >> 16));
+
+					if (seen_count < DBG_SCHED_LIMIT)
+						seen [seen_count++].qh = p.qh;
+				} else
+					temp = 0;
+				tag = Q_NEXT_TYPE(fusbh200, hw->hw_next);
+				p = p.qh->qh_next;
+				break;
+			case Q_TYPE_FSTN:
+				temp = scnprintf (next, size,
+					" fstn-%8x/%p", p.fstn->hw_prev,
+					p.fstn);
+				tag = Q_NEXT_TYPE(fusbh200, p.fstn->hw_next);
+				p = p.fstn->fstn_next;
+				break;
+			case Q_TYPE_ITD:
+				temp = scnprintf (next, size,
+					" itd/%p", p.itd);
+				tag = Q_NEXT_TYPE(fusbh200, p.itd->hw_next);
+				p = p.itd->itd_next;
+				break;
+			}
+			size -= temp;
+			next += temp;
+		} while (p.ptr);
+
+		temp = scnprintf (next, size, "\n");
+		size -= temp;
+		next += temp;
+	}
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+	kfree (seen);
+
+	return buf->alloc_size - size;
+}
+#undef DBG_SCHED_LIMIT
+
+static const char *rh_state_string(struct fusbh200_hcd *fusbh200)
+{
+	switch (fusbh200->rh_state) {
+	case FUSBH200_RH_HALTED:
+		return "halted";
+	case FUSBH200_RH_SUSPENDED:
+		return "suspended";
+	case FUSBH200_RH_RUNNING:
+		return "running";
+	case FUSBH200_RH_STOPPING:
+		return "stopping";
+	}
+	return "?";
+}
+
+static ssize_t fill_registers_buffer(struct debug_buffer *buf)
+{
+	struct usb_hcd		*hcd;
+	struct fusbh200_hcd	*fusbh200;
+	unsigned long		flags;
+	unsigned		temp, size, i;
+	char			*next, scratch [80];
+	static char		fmt [] = "%*s\n";
+	static char		label [] = "";
+
+	hcd = bus_to_hcd(buf->bus);
+	fusbh200 = hcd_to_fusbh200 (hcd);
+	next = buf->output_buf;
+	size = buf->alloc_size;
+
+	spin_lock_irqsave (&fusbh200->lock, flags);
+
+	if (!HCD_HW_ACCESSIBLE(hcd)) {
+		size = scnprintf (next, size,
+			"bus %s, device %s\n"
+			"%s\n"
+			"SUSPENDED (no register access)\n",
+			hcd->self.controller->bus->name,
+			dev_name(hcd->self.controller),
+			hcd->product_desc);
+		goto done;
+	}
+
+	/* Capability Registers */
+	i = HC_VERSION(fusbh200, fusbh200_readl(fusbh200, &fusbh200->caps->hc_capbase));
+	temp = scnprintf (next, size,
+		"bus %s, device %s\n"
+		"%s\n"
+		"EHCI %x.%02x, rh state %s\n",
+		hcd->self.controller->bus->name,
+		dev_name(hcd->self.controller),
+		hcd->product_desc,
+		i >> 8, i & 0x0ff, rh_state_string(fusbh200));
+	size -= temp;
+	next += temp;
+
+	// FIXME interpret both types of params
+	i = fusbh200_readl(fusbh200, &fusbh200->caps->hcs_params);
+	temp = scnprintf (next, size, "structural params 0x%08x\n", i);
+	size -= temp;
+	next += temp;
+
+	i = fusbh200_readl(fusbh200, &fusbh200->caps->hcc_params);
+	temp = scnprintf (next, size, "capability params 0x%08x\n", i);
+	size -= temp;
+	next += temp;
+
+	/* Operational Registers */
+	temp = dbg_status_buf (scratch, sizeof scratch, label,
+			fusbh200_readl(fusbh200, &fusbh200->regs->status));
+	temp = scnprintf (next, size, fmt, temp, scratch);
+	size -= temp;
+	next += temp;
+
+	temp = dbg_command_buf (scratch, sizeof scratch, label,
+			fusbh200_readl(fusbh200, &fusbh200->regs->command));
+	temp = scnprintf (next, size, fmt, temp, scratch);
+	size -= temp;
+	next += temp;
+
+	temp = dbg_intr_buf (scratch, sizeof scratch, label,
+			fusbh200_readl(fusbh200, &fusbh200->regs->intr_enable));
+	temp = scnprintf (next, size, fmt, temp, scratch);
+	size -= temp;
+	next += temp;
+
+	temp = scnprintf (next, size, "uframe %04x\n",
+			fusbh200_read_frame_index(fusbh200));
+	size -= temp;
+	next += temp;
+
+	if (fusbh200->async_unlink) {
+		temp = scnprintf(next, size, "async unlink qh %p\n",
+				fusbh200->async_unlink);
+		size -= temp;
+		next += temp;
+	}
+
+#ifdef FUSBH200_STATS
+	temp = scnprintf (next, size,
+		"irq normal %ld err %ld iaa %ld (lost %ld)\n",
+		fusbh200->stats.normal, fusbh200->stats.error, fusbh200->stats.iaa,
+		fusbh200->stats.lost_iaa);
+	size -= temp;
+	next += temp;
+
+	temp = scnprintf (next, size, "complete %ld unlink %ld\n",
+		fusbh200->stats.complete, fusbh200->stats.unlink);
+	size -= temp;
+	next += temp;
+#endif
+
+done:
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+
+	return buf->alloc_size - size;
+}
+
+static struct debug_buffer *alloc_buffer(struct usb_bus *bus,
+				ssize_t (*fill_func)(struct debug_buffer *))
+{
+	struct debug_buffer *buf;
+
+	buf = kzalloc(sizeof(struct debug_buffer), GFP_KERNEL);
+
+	if (buf) {
+		buf->bus = bus;
+		buf->fill_func = fill_func;
+		mutex_init(&buf->mutex);
+		buf->alloc_size = PAGE_SIZE;
+	}
+
+	return buf;
+}
+
+static int fill_buffer(struct debug_buffer *buf)
+{
+	int ret = 0;
+
+	if (!buf->output_buf)
+		buf->output_buf = vmalloc(buf->alloc_size);
+
+	if (!buf->output_buf) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ret = buf->fill_func(buf);
+
+	if (ret >= 0) {
+		buf->count = ret;
+		ret = 0;
+	}
+
+out:
+	return ret;
+}
+
+static ssize_t debug_output(struct file *file, char __user *user_buf,
+			    size_t len, loff_t *offset)
+{
+	struct debug_buffer *buf = file->private_data;
+	int ret = 0;
+
+	mutex_lock(&buf->mutex);
+	if (buf->count == 0) {
+		ret = fill_buffer(buf);
+		if (ret != 0) {
+			mutex_unlock(&buf->mutex);
+			goto out;
+		}
+	}
+	mutex_unlock(&buf->mutex);
+
+	ret = simple_read_from_buffer(user_buf, len, offset,
+				      buf->output_buf, buf->count);
+
+out:
+	return ret;
+
+}
+
+static int debug_close(struct inode *inode, struct file *file)
+{
+	struct debug_buffer *buf = file->private_data;
+
+	if (buf) {
+		vfree(buf->output_buf);
+		kfree(buf);
+	}
+
+	return 0;
+}
+static int debug_async_open(struct inode *inode, struct file *file)
+{
+	file->private_data = alloc_buffer(inode->i_private, fill_async_buffer);
+
+	return file->private_data ? 0 : -ENOMEM;
+}
+
+static int debug_periodic_open(struct inode *inode, struct file *file)
+{
+	struct debug_buffer *buf;
+	buf = alloc_buffer(inode->i_private, fill_periodic_buffer);
+	if (!buf)
+		return -ENOMEM;
+
+	buf->alloc_size = (sizeof(void *) == 4 ? 6 : 8)*PAGE_SIZE;
+	file->private_data = buf;
+	return 0;
+}
+
+static int debug_registers_open(struct inode *inode, struct file *file)
+{
+	file->private_data = alloc_buffer(inode->i_private,
+					  fill_registers_buffer);
+
+	return file->private_data ? 0 : -ENOMEM;
+}
+
+static inline void create_debug_files (struct fusbh200_hcd *fusbh200)
+{
+	struct usb_bus *bus = &fusbh200_to_hcd(fusbh200)->self;
+
+	fusbh200->debug_dir = debugfs_create_dir(bus->bus_name, fusbh200_debug_root);
+	if (!fusbh200->debug_dir)
+		return;
+
+	if (!debugfs_create_file("async", S_IRUGO, fusbh200->debug_dir, bus,
+						&debug_async_fops))
+		goto file_error;
+
+	if (!debugfs_create_file("periodic", S_IRUGO, fusbh200->debug_dir, bus,
+						&debug_periodic_fops))
+		goto file_error;
+
+	if (!debugfs_create_file("registers", S_IRUGO, fusbh200->debug_dir, bus,
+						    &debug_registers_fops))
+		goto file_error;
+
+	return;
+
+file_error:
+	debugfs_remove_recursive(fusbh200->debug_dir);
+}
+
+static inline void remove_debug_files (struct fusbh200_hcd *fusbh200)
+{
+	debugfs_remove_recursive(fusbh200->debug_dir);
+}
+
+#endif /* STUB_DEBUG_FILES */
+/*-------------------------------------------------------------------------*/
+
+/*
+ * handshake - spin reading hc until handshake completes or fails
+ * @ptr: address of hc register to be read
+ * @mask: bits to look at in result of read
+ * @done: value of those bits when handshake succeeds
+ * @usec: timeout in microseconds
+ *
+ * Returns negative errno, or zero on success
+ *
+ * Success happens when the "mask" bits have the specified value (hardware
+ * handshake done).  There are two failure modes:  "usec" have passed (major
+ * hardware flakeout), or the register reads as all-ones (hardware removed).
+ *
+ * That last failure should_only happen in cases like physical cardbus eject
+ * before driver shutdown. But it also seems to be caused by bugs in cardbus
+ * bridge shutdown:  shutting down the bridge before the devices using it.
+ */
+static int handshake (struct fusbh200_hcd *fusbh200, void __iomem *ptr,
+		      u32 mask, u32 done, int usec)
+{
+	u32	result;
+
+	do {
+		result = fusbh200_readl(fusbh200, ptr);
+		if (result == ~(u32)0)		/* card removed */
+			return -ENODEV;
+		result &= mask;
+		if (result == done)
+			return 0;
+		udelay (1);
+		usec--;
+	} while (usec > 0);
+	return -ETIMEDOUT;
+}
+
+/*
+ * Force HC to halt state from unknown (EHCI spec section 2.3).
+ * Must be called with interrupts enabled and the lock not held.
+ */
+static int fusbh200_halt (struct fusbh200_hcd *fusbh200)
+{
+	u32	temp;
+
+	spin_lock_irq(&fusbh200->lock);
+
+	/* disable any irqs left enabled by previous code */
+	fusbh200_writel(fusbh200, 0, &fusbh200->regs->intr_enable);
+
+	/*
+	 * This routine gets called during probe before fusbh200->command
+	 * has been initialized, so we can't rely on its value.
+	 */
+	fusbh200->command &= ~CMD_RUN;
+	temp = fusbh200_readl(fusbh200, &fusbh200->regs->command);
+	temp &= ~(CMD_RUN | CMD_IAAD);
+	fusbh200_writel(fusbh200, temp, &fusbh200->regs->command);
+
+	spin_unlock_irq(&fusbh200->lock);
+	synchronize_irq(fusbh200_to_hcd(fusbh200)->irq);
+
+	return handshake(fusbh200, &fusbh200->regs->status,
+			  STS_HALT, STS_HALT, 16 * 125);
+}
+
+/*
+ * Reset a non-running (STS_HALT == 1) controller.
+ * Must be called with interrupts enabled and the lock not held.
+ */
+static int fusbh200_reset (struct fusbh200_hcd *fusbh200)
+{
+	int	retval;
+	u32	command = fusbh200_readl(fusbh200, &fusbh200->regs->command);
+
+	/* If the EHCI debug controller is active, special care must be
+	 * taken before and after a host controller reset */
+	if (fusbh200->debug && !dbgp_reset_prep(fusbh200_to_hcd(fusbh200)))
+		fusbh200->debug = NULL;
+
+	command |= CMD_RESET;
+	dbg_cmd (fusbh200, "reset", command);
+	fusbh200_writel(fusbh200, command, &fusbh200->regs->command);
+	fusbh200->rh_state = FUSBH200_RH_HALTED;
+	fusbh200->next_statechange = jiffies;
+	retval = handshake (fusbh200, &fusbh200->regs->command,
+			    CMD_RESET, 0, 250 * 1000);
+
+	if (retval)
+		return retval;
+
+	if (fusbh200->debug)
+		dbgp_external_startup(fusbh200_to_hcd(fusbh200));
+
+	fusbh200->port_c_suspend = fusbh200->suspended_ports =
+			fusbh200->resuming_ports = 0;
+	return retval;
+}
+
+/*
+ * Idle the controller (turn off the schedules).
+ * Must be called with interrupts enabled and the lock not held.
+ */
+static void fusbh200_quiesce (struct fusbh200_hcd *fusbh200)
+{
+	u32	temp;
+
+	if (fusbh200->rh_state != FUSBH200_RH_RUNNING)
+		return;
+
+	/* wait for any schedule enables/disables to take effect */
+	temp = (fusbh200->command << 10) & (STS_ASS | STS_PSS);
+	handshake(fusbh200, &fusbh200->regs->status, STS_ASS | STS_PSS, temp, 16 * 125);
+
+	/* then disable anything that's still active */
+	spin_lock_irq(&fusbh200->lock);
+	fusbh200->command &= ~(CMD_ASE | CMD_PSE);
+	fusbh200_writel(fusbh200, fusbh200->command, &fusbh200->regs->command);
+	spin_unlock_irq(&fusbh200->lock);
+
+	/* hardware can take 16 microframes to turn off ... */
+	handshake(fusbh200, &fusbh200->regs->status, STS_ASS | STS_PSS, 0, 16 * 125);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void end_unlink_async(struct fusbh200_hcd *fusbh200);
+static void unlink_empty_async(struct fusbh200_hcd *fusbh200);
+static void fusbh200_work(struct fusbh200_hcd *fusbh200);
+static void start_unlink_intr(struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh);
+static void end_unlink_intr(struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh);
+
+/*-------------------------------------------------------------------------*/
+
+/* Set a bit in the USBCMD register */
+static void fusbh200_set_command_bit(struct fusbh200_hcd *fusbh200, u32 bit)
+{
+	fusbh200->command |= bit;
+	fusbh200_writel(fusbh200, fusbh200->command, &fusbh200->regs->command);
+
+	/* unblock posted write */
+	fusbh200_readl(fusbh200, &fusbh200->regs->command);
+}
+
+/* Clear a bit in the USBCMD register */
+static void fusbh200_clear_command_bit(struct fusbh200_hcd *fusbh200, u32 bit)
+{
+	fusbh200->command &= ~bit;
+	fusbh200_writel(fusbh200, fusbh200->command, &fusbh200->regs->command);
+
+	/* unblock posted write */
+	fusbh200_readl(fusbh200, &fusbh200->regs->command);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * EHCI timer support...  Now using hrtimers.
+ *
+ * Lots of different events are triggered from fusbh200->hrtimer.  Whenever
+ * the timer routine runs, it checks each possible event; events that are
+ * currently enabled and whose expiration time has passed get handled.
+ * The set of enabled events is stored as a collection of bitflags in
+ * fusbh200->enabled_hrtimer_events, and they are numbered in order of
+ * increasing delay values (ranging between 1 ms and 100 ms).
+ *
+ * Rather than implementing a sorted list or tree of all pending events,
+ * we keep track only of the lowest-numbered pending event, in
+ * fusbh200->next_hrtimer_event.  Whenever fusbh200->hrtimer gets restarted, its
+ * expiration time is set to the timeout value for this event.
+ *
+ * As a result, events might not get handled right away; the actual delay
+ * could be anywhere up to twice the requested delay.  This doesn't
+ * matter, because none of the events are especially time-critical.  The
+ * ones that matter most all have a delay of 1 ms, so they will be
+ * handled after 2 ms at most, which is okay.  In addition to this, we
+ * allow for an expiration range of 1 ms.
+ */
+
+/*
+ * Delay lengths for the hrtimer event types.
+ * Keep this list sorted by delay length, in the same order as
+ * the event types indexed by enum fusbh200_hrtimer_event in fusbh200.h.
+ */
+static unsigned event_delays_ns[] = {
+	1 * NSEC_PER_MSEC,	/* FUSBH200_HRTIMER_POLL_ASS */
+	1 * NSEC_PER_MSEC,	/* FUSBH200_HRTIMER_POLL_PSS */
+	1 * NSEC_PER_MSEC,	/* FUSBH200_HRTIMER_POLL_DEAD */
+	1125 * NSEC_PER_USEC,	/* FUSBH200_HRTIMER_UNLINK_INTR */
+	2 * NSEC_PER_MSEC,	/* FUSBH200_HRTIMER_FREE_ITDS */
+	6 * NSEC_PER_MSEC,	/* FUSBH200_HRTIMER_ASYNC_UNLINKS */
+	10 * NSEC_PER_MSEC,	/* FUSBH200_HRTIMER_IAA_WATCHDOG */
+	10 * NSEC_PER_MSEC,	/* FUSBH200_HRTIMER_DISABLE_PERIODIC */
+	15 * NSEC_PER_MSEC,	/* FUSBH200_HRTIMER_DISABLE_ASYNC */
+	100 * NSEC_PER_MSEC,	/* FUSBH200_HRTIMER_IO_WATCHDOG */
+};
+
+/* Enable a pending hrtimer event */
+static void fusbh200_enable_event(struct fusbh200_hcd *fusbh200, unsigned event,
+		bool resched)
+{
+	ktime_t		*timeout = &fusbh200->hr_timeouts[event];
+
+	if (resched)
+		*timeout = ktime_add(ktime_get(),
+				ktime_set(0, event_delays_ns[event]));
+	fusbh200->enabled_hrtimer_events |= (1 << event);
+
+	/* Track only the lowest-numbered pending event */
+	if (event < fusbh200->next_hrtimer_event) {
+		fusbh200->next_hrtimer_event = event;
+		hrtimer_start_range_ns(&fusbh200->hrtimer, *timeout,
+				NSEC_PER_MSEC, HRTIMER_MODE_ABS);
+	}
+}
+
+
+/* Poll the STS_ASS status bit; see when it agrees with CMD_ASE */
+static void fusbh200_poll_ASS(struct fusbh200_hcd *fusbh200)
+{
+	unsigned	actual, want;
+
+	/* Don't enable anything if the controller isn't running (e.g., died) */
+	if (fusbh200->rh_state != FUSBH200_RH_RUNNING)
+		return;
+
+	want = (fusbh200->command & CMD_ASE) ? STS_ASS : 0;
+	actual = fusbh200_readl(fusbh200, &fusbh200->regs->status) & STS_ASS;
+
+	if (want != actual) {
+
+		/* Poll again later, but give up after about 20 ms */
+		if (fusbh200->ASS_poll_count++ < 20) {
+			fusbh200_enable_event(fusbh200, FUSBH200_HRTIMER_POLL_ASS, true);
+			return;
+		}
+		fusbh200_dbg(fusbh200, "Waited too long for the async schedule status (%x/%x), giving up\n",
+				want, actual);
+	}
+	fusbh200->ASS_poll_count = 0;
+
+	/* The status is up-to-date; restart or stop the schedule as needed */
+	if (want == 0) {	/* Stopped */
+		if (fusbh200->async_count > 0)
+			fusbh200_set_command_bit(fusbh200, CMD_ASE);
+
+	} else {		/* Running */
+		if (fusbh200->async_count == 0) {
+
+			/* Turn off the schedule after a while */
+			fusbh200_enable_event(fusbh200, FUSBH200_HRTIMER_DISABLE_ASYNC,
+					true);
+		}
+	}
+}
+
+/* Turn off the async schedule after a brief delay */
+static void fusbh200_disable_ASE(struct fusbh200_hcd *fusbh200)
+{
+	fusbh200_clear_command_bit(fusbh200, CMD_ASE);
+}
+
+
+/* Poll the STS_PSS status bit; see when it agrees with CMD_PSE */
+static void fusbh200_poll_PSS(struct fusbh200_hcd *fusbh200)
+{
+	unsigned	actual, want;
+
+	/* Don't do anything if the controller isn't running (e.g., died) */
+	if (fusbh200->rh_state != FUSBH200_RH_RUNNING)
+		return;
+
+	want = (fusbh200->command & CMD_PSE) ? STS_PSS : 0;
+	actual = fusbh200_readl(fusbh200, &fusbh200->regs->status) & STS_PSS;
+
+	if (want != actual) {
+
+		/* Poll again later, but give up after about 20 ms */
+		if (fusbh200->PSS_poll_count++ < 20) {
+			fusbh200_enable_event(fusbh200, FUSBH200_HRTIMER_POLL_PSS, true);
+			return;
+		}
+		fusbh200_dbg(fusbh200, "Waited too long for the periodic schedule status (%x/%x), giving up\n",
+				want, actual);
+	}
+	fusbh200->PSS_poll_count = 0;
+
+	/* The status is up-to-date; restart or stop the schedule as needed */
+	if (want == 0) {	/* Stopped */
+		if (fusbh200->periodic_count > 0)
+			fusbh200_set_command_bit(fusbh200, CMD_PSE);
+
+	} else {		/* Running */
+		if (fusbh200->periodic_count == 0) {
+
+			/* Turn off the schedule after a while */
+			fusbh200_enable_event(fusbh200, FUSBH200_HRTIMER_DISABLE_PERIODIC,
+					true);
+		}
+	}
+}
+
+/* Turn off the periodic schedule after a brief delay */
+static void fusbh200_disable_PSE(struct fusbh200_hcd *fusbh200)
+{
+	fusbh200_clear_command_bit(fusbh200, CMD_PSE);
+}
+
+
+/* Poll the STS_HALT status bit; see when a dead controller stops */
+static void fusbh200_handle_controller_death(struct fusbh200_hcd *fusbh200)
+{
+	if (!(fusbh200_readl(fusbh200, &fusbh200->regs->status) & STS_HALT)) {
+
+		/* Give up after a few milliseconds */
+		if (fusbh200->died_poll_count++ < 5) {
+			/* Try again later */
+			fusbh200_enable_event(fusbh200, FUSBH200_HRTIMER_POLL_DEAD, true);
+			return;
+		}
+		fusbh200_warn(fusbh200, "Waited too long for the controller to stop, giving up\n");
+	}
+
+	/* Clean up the mess */
+	fusbh200->rh_state = FUSBH200_RH_HALTED;
+	fusbh200_writel(fusbh200, 0, &fusbh200->regs->intr_enable);
+	fusbh200_work(fusbh200);
+	end_unlink_async(fusbh200);
+
+	/* Not in process context, so don't try to reset the controller */
+}
+
+
+/* Handle unlinked interrupt QHs once they are gone from the hardware */
+static void fusbh200_handle_intr_unlinks(struct fusbh200_hcd *fusbh200)
+{
+	bool		stopped = (fusbh200->rh_state < FUSBH200_RH_RUNNING);
+
+	/*
+	 * Process all the QHs on the intr_unlink list that were added
+	 * before the current unlink cycle began.  The list is in
+	 * temporal order, so stop when we reach the first entry in the
+	 * current cycle.  But if the root hub isn't running then
+	 * process all the QHs on the list.
+	 */
+	fusbh200->intr_unlinking = true;
+	while (fusbh200->intr_unlink) {
+		struct fusbh200_qh	*qh = fusbh200->intr_unlink;
+
+		if (!stopped && qh->unlink_cycle == fusbh200->intr_unlink_cycle)
+			break;
+		fusbh200->intr_unlink = qh->unlink_next;
+		qh->unlink_next = NULL;
+		end_unlink_intr(fusbh200, qh);
+	}
+
+	/* Handle remaining entries later */
+	if (fusbh200->intr_unlink) {
+		fusbh200_enable_event(fusbh200, FUSBH200_HRTIMER_UNLINK_INTR, true);
+		++fusbh200->intr_unlink_cycle;
+	}
+	fusbh200->intr_unlinking = false;
+}
+
+
+/* Start another free-iTDs/siTDs cycle */
+static void start_free_itds(struct fusbh200_hcd *fusbh200)
+{
+	if (!(fusbh200->enabled_hrtimer_events & BIT(FUSBH200_HRTIMER_FREE_ITDS))) {
+		fusbh200->last_itd_to_free = list_entry(
+				fusbh200->cached_itd_list.prev,
+				struct fusbh200_itd, itd_list);
+		fusbh200_enable_event(fusbh200, FUSBH200_HRTIMER_FREE_ITDS, true);
+	}
+}
+
+/* Wait for controller to stop using old iTDs and siTDs */
+static void end_free_itds(struct fusbh200_hcd *fusbh200)
+{
+	struct fusbh200_itd		*itd, *n;
+
+	if (fusbh200->rh_state < FUSBH200_RH_RUNNING) {
+		fusbh200->last_itd_to_free = NULL;
+	}
+
+	list_for_each_entry_safe(itd, n, &fusbh200->cached_itd_list, itd_list) {
+		list_del(&itd->itd_list);
+		dma_pool_free(fusbh200->itd_pool, itd, itd->itd_dma);
+		if (itd == fusbh200->last_itd_to_free)
+			break;
+	}
+
+	if (!list_empty(&fusbh200->cached_itd_list))
+		start_free_itds(fusbh200);
+}
+
+
+/* Handle lost (or very late) IAA interrupts */
+static void fusbh200_iaa_watchdog(struct fusbh200_hcd *fusbh200)
+{
+	if (fusbh200->rh_state != FUSBH200_RH_RUNNING)
+		return;
+
+	/*
+	 * Lost IAA irqs wedge things badly; seen first with a vt8235.
+	 * So we need this watchdog, but must protect it against both
+	 * (a) SMP races against real IAA firing and retriggering, and
+	 * (b) clean HC shutdown, when IAA watchdog was pending.
+	 */
+	if (fusbh200->async_iaa) {
+		u32 cmd, status;
+
+		/* If we get here, IAA is *REALLY* late.  It's barely
+		 * conceivable that the system is so busy that CMD_IAAD
+		 * is still legitimately set, so let's be sure it's
+		 * clear before we read STS_IAA.  (The HC should clear
+		 * CMD_IAAD when it sets STS_IAA.)
+		 */
+		cmd = fusbh200_readl(fusbh200, &fusbh200->regs->command);
+
+		/*
+		 * If IAA is set here it either legitimately triggered
+		 * after the watchdog timer expired (_way_ late, so we'll
+		 * still count it as lost) ... or a silicon erratum:
+		 * - VIA seems to set IAA without triggering the IRQ;
+		 * - IAAD potentially cleared without setting IAA.
+		 */
+		status = fusbh200_readl(fusbh200, &fusbh200->regs->status);
+		if ((status & STS_IAA) || !(cmd & CMD_IAAD)) {
+			COUNT(fusbh200->stats.lost_iaa);
+			fusbh200_writel(fusbh200, STS_IAA, &fusbh200->regs->status);
+		}
+
+		fusbh200_vdbg(fusbh200, "IAA watchdog: status %x cmd %x\n",
+				status, cmd);
+		end_unlink_async(fusbh200);
+	}
+}
+
+
+/* Enable the I/O watchdog, if appropriate */
+static void turn_on_io_watchdog(struct fusbh200_hcd *fusbh200)
+{
+	/* Not needed if the controller isn't running or it's already enabled */
+	if (fusbh200->rh_state != FUSBH200_RH_RUNNING ||
+			(fusbh200->enabled_hrtimer_events &
+				BIT(FUSBH200_HRTIMER_IO_WATCHDOG)))
+		return;
+
+	/*
+	 * Isochronous transfers always need the watchdog.
+	 * For other sorts we use it only if the flag is set.
+	 */
+	if (fusbh200->isoc_count > 0 || (fusbh200->need_io_watchdog &&
+			fusbh200->async_count + fusbh200->intr_count > 0))
+		fusbh200_enable_event(fusbh200, FUSBH200_HRTIMER_IO_WATCHDOG, true);
+}
+
+
+/*
+ * Handler functions for the hrtimer event types.
+ * Keep this array in the same order as the event types indexed by
+ * enum fusbh200_hrtimer_event in fusbh200.h.
+ */
+static void (*event_handlers[])(struct fusbh200_hcd *) = {
+	fusbh200_poll_ASS,			/* FUSBH200_HRTIMER_POLL_ASS */
+	fusbh200_poll_PSS,			/* FUSBH200_HRTIMER_POLL_PSS */
+	fusbh200_handle_controller_death,	/* FUSBH200_HRTIMER_POLL_DEAD */
+	fusbh200_handle_intr_unlinks,	/* FUSBH200_HRTIMER_UNLINK_INTR */
+	end_free_itds,			/* FUSBH200_HRTIMER_FREE_ITDS */
+	unlink_empty_async,		/* FUSBH200_HRTIMER_ASYNC_UNLINKS */
+	fusbh200_iaa_watchdog,		/* FUSBH200_HRTIMER_IAA_WATCHDOG */
+	fusbh200_disable_PSE,		/* FUSBH200_HRTIMER_DISABLE_PERIODIC */
+	fusbh200_disable_ASE,		/* FUSBH200_HRTIMER_DISABLE_ASYNC */
+	fusbh200_work,			/* FUSBH200_HRTIMER_IO_WATCHDOG */
+};
+
+static enum hrtimer_restart fusbh200_hrtimer_func(struct hrtimer *t)
+{
+	struct fusbh200_hcd	*fusbh200 = container_of(t, struct fusbh200_hcd, hrtimer);
+	ktime_t		now;
+	unsigned long	events;
+	unsigned long	flags;
+	unsigned	e;
+
+	spin_lock_irqsave(&fusbh200->lock, flags);
+
+	events = fusbh200->enabled_hrtimer_events;
+	fusbh200->enabled_hrtimer_events = 0;
+	fusbh200->next_hrtimer_event = FUSBH200_HRTIMER_NO_EVENT;
+
+	/*
+	 * Check each pending event.  If its time has expired, handle
+	 * the event; otherwise re-enable it.
+	 */
+	now = ktime_get();
+	for_each_set_bit(e, &events, FUSBH200_HRTIMER_NUM_EVENTS) {
+		if (now.tv64 >= fusbh200->hr_timeouts[e].tv64)
+			event_handlers[e](fusbh200);
+		else
+			fusbh200_enable_event(fusbh200, e, false);
+	}
+
+	spin_unlock_irqrestore(&fusbh200->lock, flags);
+	return HRTIMER_NORESTART;
+}
+
+/*-------------------------------------------------------------------------*/
+
+#define fusbh200_bus_suspend	NULL
+#define fusbh200_bus_resume	NULL
+
+/*-------------------------------------------------------------------------*/
+
+static int check_reset_complete (
+	struct fusbh200_hcd	*fusbh200,
+	int		index,
+	u32 __iomem	*status_reg,
+	int		port_status
+) {
+	if (!(port_status & PORT_CONNECT))
+		return port_status;
+
+	/* if reset finished and it's still not enabled -- handoff */
+	if (!(port_status & PORT_PE)) {
+		/* with integrated TT, there's nobody to hand it to! */
+		fusbh200_dbg (fusbh200,
+			"Failed to enable port %d on root hub TT\n",
+			index+1);
+		return port_status;
+	} else {
+		fusbh200_dbg(fusbh200, "port %d reset complete, port enabled\n",
+			index + 1);
+	}
+
+	return port_status;
+}
+
+/*-------------------------------------------------------------------------*/
+
+
+/* build "status change" packet (one or two bytes) from HC registers */
+
+static int
+fusbh200_hub_status_data (struct usb_hcd *hcd, char *buf)
+{
+	struct fusbh200_hcd	*fusbh200 = hcd_to_fusbh200 (hcd);
+	u32		temp, status;
+	u32		mask;
+	int		retval = 1;
+	unsigned long	flags;
+
+	/* init status to no-changes */
+	buf [0] = 0;
+
+	/* Inform the core about resumes-in-progress by returning
+	 * a non-zero value even if there are no status changes.
+	 */
+	status = fusbh200->resuming_ports;
+
+	mask = PORT_CSC | PORT_PEC;
+	// PORT_RESUME from hardware ~= PORT_STAT_C_SUSPEND
+
+	/* no hub change reports (bit 0) for now (power, ...) */
+
+	/* port N changes (bit N)? */
+	spin_lock_irqsave (&fusbh200->lock, flags);
+
+	temp = fusbh200_readl(fusbh200, &fusbh200->regs->port_status);
+
+	/*
+	 * Return status information even for ports with OWNER set.
+	 * Otherwise khubd wouldn't see the disconnect event when a
+	 * high-speed device is switched over to the companion
+	 * controller by the user.
+	 */
+
+	if ((temp & mask) != 0 || test_bit(0, &fusbh200->port_c_suspend)
+			|| (fusbh200->reset_done[0] && time_after_eq(
+				jiffies, fusbh200->reset_done[0]))) {
+		buf [0] |= 1 << 1;
+		status = STS_PCD;
+	}
+	/* FIXME autosuspend idle root hubs */
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+	return status ? retval : 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void
+fusbh200_hub_descriptor (
+	struct fusbh200_hcd		*fusbh200,
+	struct usb_hub_descriptor	*desc
+) {
+	int		ports = HCS_N_PORTS (fusbh200->hcs_params);
+	u16		temp;
+
+	desc->bDescriptorType = 0x29;
+	desc->bPwrOn2PwrGood = 10;	/* fusbh200 1.0, 2.3.9 says 20ms max */
+	desc->bHubContrCurrent = 0;
+
+	desc->bNbrPorts = ports;
+	temp = 1 + (ports / 8);
+	desc->bDescLength = 7 + 2 * temp;
+
+	/* two bitmaps:  ports removable, and usb 1.0 legacy PortPwrCtrlMask */
+	memset(&desc->u.hs.DeviceRemovable[0], 0, temp);
+	memset(&desc->u.hs.DeviceRemovable[temp], 0xff, temp);
+
+	temp = 0x0008;		/* per-port overcurrent reporting */
+	temp |= 0x0002;		/* no power switching */
+	desc->wHubCharacteristics = cpu_to_le16(temp);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int fusbh200_hub_control (
+	struct usb_hcd	*hcd,
+	u16		typeReq,
+	u16		wValue,
+	u16		wIndex,
+	char		*buf,
+	u16		wLength
+) {
+	struct fusbh200_hcd	*fusbh200 = hcd_to_fusbh200 (hcd);
+	int		ports = HCS_N_PORTS (fusbh200->hcs_params);
+	u32 __iomem	*status_reg = &fusbh200->regs->port_status;
+	u32		temp, temp1, status;
+	unsigned long	flags;
+	int		retval = 0;
+	unsigned	selector;
+
+	/*
+	 * FIXME:  support SetPortFeatures USB_PORT_FEAT_INDICATOR.
+	 * HCS_INDICATOR may say we can change LEDs to off/amber/green.
+	 * (track current state ourselves) ... blink for diagnostics,
+	 * power, "this is the one", etc.  EHCI spec supports this.
+	 */
+
+	spin_lock_irqsave (&fusbh200->lock, flags);
+	switch (typeReq) {
+	case ClearHubFeature:
+		switch (wValue) {
+		case C_HUB_LOCAL_POWER:
+		case C_HUB_OVER_CURRENT:
+			/* no hub-wide feature/status flags */
+			break;
+		default:
+			goto error;
+		}
+		break;
+	case ClearPortFeature:
+		if (!wIndex || wIndex > ports)
+			goto error;
+		wIndex--;
+		temp = fusbh200_readl(fusbh200, status_reg);
+		temp &= ~PORT_RWC_BITS;
+
+		/*
+		 * Even if OWNER is set, so the port is owned by the
+		 * companion controller, khubd needs to be able to clear
+		 * the port-change status bits (especially
+		 * USB_PORT_STAT_C_CONNECTION).
+		 */
+
+		switch (wValue) {
+		case USB_PORT_FEAT_ENABLE:
+			fusbh200_writel(fusbh200, temp & ~PORT_PE, status_reg);
+			break;
+		case USB_PORT_FEAT_C_ENABLE:
+			fusbh200_writel(fusbh200, temp | PORT_PEC, status_reg);
+			break;
+		case USB_PORT_FEAT_SUSPEND:
+			if (temp & PORT_RESET)
+				goto error;
+			if (!(temp & PORT_SUSPEND))
+				break;
+			if ((temp & PORT_PE) == 0)
+				goto error;
+
+			/* resume signaling for 20 msec */
+			fusbh200_writel(fusbh200, temp | PORT_RESUME, status_reg);
+			fusbh200->reset_done[wIndex] = jiffies
+					+ msecs_to_jiffies(20);
+			break;
+		case USB_PORT_FEAT_C_SUSPEND:
+			clear_bit(wIndex, &fusbh200->port_c_suspend);
+			break;
+		case USB_PORT_FEAT_C_CONNECTION:
+			fusbh200_writel(fusbh200, temp | PORT_CSC, status_reg);
+			break;
+		case USB_PORT_FEAT_C_OVER_CURRENT:
+			fusbh200_writel(fusbh200, temp | BMISR_OVC, &fusbh200->regs->bmisr);
+			break;
+		case USB_PORT_FEAT_C_RESET:
+			/* GetPortStatus clears reset */
+			break;
+		default:
+			goto error;
+		}
+		fusbh200_readl(fusbh200, &fusbh200->regs->command);	/* unblock posted write */
+		break;
+	case GetHubDescriptor:
+		fusbh200_hub_descriptor (fusbh200, (struct usb_hub_descriptor *)
+			buf);
+		break;
+	case GetHubStatus:
+		/* no hub-wide feature/status flags */
+		memset (buf, 0, 4);
+		//cpu_to_le32s ((u32 *) buf);
+		break;
+	case GetPortStatus:
+		if (!wIndex || wIndex > ports)
+			goto error;
+		wIndex--;
+		status = 0;
+		temp = fusbh200_readl(fusbh200, status_reg);
+
+		// wPortChange bits
+		if (temp & PORT_CSC)
+			status |= USB_PORT_STAT_C_CONNECTION << 16;
+		if (temp & PORT_PEC)
+			status |= USB_PORT_STAT_C_ENABLE << 16;
+
+		temp1 = fusbh200_readl(fusbh200, &fusbh200->regs->bmisr);
+		if (temp1 & BMISR_OVC)
+			status |= USB_PORT_STAT_C_OVERCURRENT << 16;
+
+		/* whoever resumes must GetPortStatus to complete it!! */
+		if (temp & PORT_RESUME) {
+
+			/* Remote Wakeup received? */
+			if (!fusbh200->reset_done[wIndex]) {
+				/* resume signaling for 20 msec */
+				fusbh200->reset_done[wIndex] = jiffies
+						+ msecs_to_jiffies(20);
+				/* check the port again */
+				mod_timer(&fusbh200_to_hcd(fusbh200)->rh_timer,
+						fusbh200->reset_done[wIndex]);
+			}
+
+			/* resume completed? */
+			else if (time_after_eq(jiffies,
+					fusbh200->reset_done[wIndex])) {
+				clear_bit(wIndex, &fusbh200->suspended_ports);
+				set_bit(wIndex, &fusbh200->port_c_suspend);
+				fusbh200->reset_done[wIndex] = 0;
+
+				/* stop resume signaling */
+				temp = fusbh200_readl(fusbh200, status_reg);
+				fusbh200_writel(fusbh200,
+					temp & ~(PORT_RWC_BITS | PORT_RESUME),
+					status_reg);
+				clear_bit(wIndex, &fusbh200->resuming_ports);
+				retval = handshake(fusbh200, status_reg,
+					   PORT_RESUME, 0, 2000 /* 2msec */);
+				if (retval != 0) {
+					fusbh200_err(fusbh200,
+						"port %d resume error %d\n",
+						wIndex + 1, retval);
+					goto error;
+				}
+				temp &= ~(PORT_SUSPEND|PORT_RESUME|(3<<10));
+			}
+		}
+
+		/* whoever resets must GetPortStatus to complete it!! */
+		if ((temp & PORT_RESET)
+				&& time_after_eq(jiffies,
+					fusbh200->reset_done[wIndex])) {
+			status |= USB_PORT_STAT_C_RESET << 16;
+			fusbh200->reset_done [wIndex] = 0;
+			clear_bit(wIndex, &fusbh200->resuming_ports);
+
+			/* force reset to complete */
+			fusbh200_writel(fusbh200, temp & ~(PORT_RWC_BITS | PORT_RESET),
+					status_reg);
+			/* REVISIT:  some hardware needs 550+ usec to clear
+			 * this bit; seems too long to spin routinely...
+			 */
+			retval = handshake(fusbh200, status_reg,
+					PORT_RESET, 0, 1000);
+			if (retval != 0) {
+				fusbh200_err (fusbh200, "port %d reset error %d\n",
+					wIndex + 1, retval);
+				goto error;
+			}
+
+			/* see what we found out */
+			temp = check_reset_complete (fusbh200, wIndex, status_reg,
+					fusbh200_readl(fusbh200, status_reg));
+		}
+
+		if (!(temp & (PORT_RESUME|PORT_RESET))) {
+			fusbh200->reset_done[wIndex] = 0;
+			clear_bit(wIndex, &fusbh200->resuming_ports);
+		}
+
+		/* transfer dedicated ports to the companion hc */
+		if ((temp & PORT_CONNECT) &&
+				test_bit(wIndex, &fusbh200->companion_ports)) {
+			temp &= ~PORT_RWC_BITS;
+			fusbh200_writel(fusbh200, temp, status_reg);
+			fusbh200_dbg(fusbh200, "port %d --> companion\n", wIndex + 1);
+			temp = fusbh200_readl(fusbh200, status_reg);
+		}
+
+		/*
+		 * Even if OWNER is set, there's no harm letting khubd
+		 * see the wPortStatus values (they should all be 0 except
+		 * for PORT_POWER anyway).
+		 */
+
+		if (temp & PORT_CONNECT) {
+			status |= USB_PORT_STAT_CONNECTION;
+			status |= fusbh200_port_speed(fusbh200, temp);
+		}
+		if (temp & PORT_PE)
+			status |= USB_PORT_STAT_ENABLE;
+
+		/* maybe the port was unsuspended without our knowledge */
+		if (temp & (PORT_SUSPEND|PORT_RESUME)) {
+			status |= USB_PORT_STAT_SUSPEND;
+		} else if (test_bit(wIndex, &fusbh200->suspended_ports)) {
+			clear_bit(wIndex, &fusbh200->suspended_ports);
+			clear_bit(wIndex, &fusbh200->resuming_ports);
+			fusbh200->reset_done[wIndex] = 0;
+			if (temp & PORT_PE)
+				set_bit(wIndex, &fusbh200->port_c_suspend);
+		}
+
+		temp1 = fusbh200_readl(fusbh200, &fusbh200->regs->bmisr);
+		if (temp1 & BMISR_OVC)
+			status |= USB_PORT_STAT_OVERCURRENT;
+		if (temp & PORT_RESET)
+			status |= USB_PORT_STAT_RESET;
+		if (test_bit(wIndex, &fusbh200->port_c_suspend))
+			status |= USB_PORT_STAT_C_SUSPEND << 16;
+
+#ifndef	VERBOSE_DEBUG
+	if (status & ~0xffff)	/* only if wPortChange is interesting */
+#endif
+		dbg_port (fusbh200, "GetStatus", wIndex + 1, temp);
+		put_unaligned_le32(status, buf);
+		break;
+	case SetHubFeature:
+		switch (wValue) {
+		case C_HUB_LOCAL_POWER:
+		case C_HUB_OVER_CURRENT:
+			/* no hub-wide feature/status flags */
+			break;
+		default:
+			goto error;
+		}
+		break;
+	case SetPortFeature:
+		selector = wIndex >> 8;
+		wIndex &= 0xff;
+
+		if (!wIndex || wIndex > ports)
+			goto error;
+		wIndex--;
+		temp = fusbh200_readl(fusbh200, status_reg);
+		temp &= ~PORT_RWC_BITS;
+		switch (wValue) {
+		case USB_PORT_FEAT_SUSPEND:
+			if ((temp & PORT_PE) == 0
+					|| (temp & PORT_RESET) != 0)
+				goto error;
+
+			/* After above check the port must be connected.
+			 * Set appropriate bit thus could put phy into low power
+			 * mode if we have hostpc feature
+			 */
+			fusbh200_writel(fusbh200, temp | PORT_SUSPEND, status_reg);
+			set_bit(wIndex, &fusbh200->suspended_ports);
+			break;
+		case USB_PORT_FEAT_RESET:
+			if (temp & PORT_RESUME)
+				goto error;
+			/* line status bits may report this as low speed,
+			 * which can be fine if this root hub has a
+			 * transaction translator built in.
+			 */
+			fusbh200_vdbg (fusbh200, "port %d reset\n", wIndex + 1);
+			temp |= PORT_RESET;
+			temp &= ~PORT_PE;
+
+			/*
+			 * caller must wait, then call GetPortStatus
+			 * usb 2.0 spec says 50 ms resets on root
+			 */
+			fusbh200->reset_done [wIndex] = jiffies
+					+ msecs_to_jiffies (50);
+			fusbh200_writel(fusbh200, temp, status_reg);
+			break;
+
+		/* For downstream facing ports (these):  one hub port is put
+		 * into test mode according to USB2 11.24.2.13, then the hub
+		 * must be reset (which for root hub now means rmmod+modprobe,
+		 * or else system reboot).  See EHCI 2.3.9 and 4.14 for info
+		 * about the EHCI-specific stuff.
+		 */
+		case USB_PORT_FEAT_TEST:
+			if (!selector || selector > 5)
+				goto error;
+			spin_unlock_irqrestore(&fusbh200->lock, flags);
+			fusbh200_quiesce(fusbh200);
+			spin_lock_irqsave(&fusbh200->lock, flags);
+
+			/* Put all enabled ports into suspend */
+			temp = fusbh200_readl(fusbh200, status_reg) & ~PORT_RWC_BITS;
+			if (temp & PORT_PE)
+				fusbh200_writel(fusbh200, temp | PORT_SUSPEND,
+						status_reg);
+
+			spin_unlock_irqrestore(&fusbh200->lock, flags);
+			fusbh200_halt(fusbh200);
+			spin_lock_irqsave(&fusbh200->lock, flags);
+
+			temp = fusbh200_readl(fusbh200, status_reg);
+			temp |= selector << 16;
+			fusbh200_writel(fusbh200, temp, status_reg);
+			break;
+
+		default:
+			goto error;
+		}
+		fusbh200_readl(fusbh200, &fusbh200->regs->command);	/* unblock posted writes */
+		break;
+
+	default:
+error:
+		/* "stall" on error */
+		retval = -EPIPE;
+	}
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+	return retval;
+}
+
+static void __maybe_unused fusbh200_relinquish_port(struct usb_hcd *hcd,
+		int portnum)
+{
+	return;
+}
+
+static int __maybe_unused fusbh200_port_handed_over(struct usb_hcd *hcd,
+		int portnum)
+{
+	return 0;
+}
+/*-------------------------------------------------------------------------*/
+/*
+ * There's basically three types of memory:
+ *	- data used only by the HCD ... kmalloc is fine
+ *	- async and periodic schedules, shared by HC and HCD ... these
+ *	  need to use dma_pool or dma_alloc_coherent
+ *	- driver buffers, read/written by HC ... single shot DMA mapped
+ *
+ * There's also "register" data (e.g. PCI or SOC), which is memory mapped.
+ * No memory seen by this driver is pageable.
+ */
+
+/*-------------------------------------------------------------------------*/
+
+/* Allocate the key transfer structures from the previously allocated pool */
+
+static inline void fusbh200_qtd_init(struct fusbh200_hcd *fusbh200, struct fusbh200_qtd *qtd,
+				  dma_addr_t dma)
+{
+	memset (qtd, 0, sizeof *qtd);
+	qtd->qtd_dma = dma;
+	qtd->hw_token = cpu_to_hc32(fusbh200, QTD_STS_HALT);
+	qtd->hw_next = FUSBH200_LIST_END(fusbh200);
+	qtd->hw_alt_next = FUSBH200_LIST_END(fusbh200);
+	INIT_LIST_HEAD (&qtd->qtd_list);
+}
+
+static struct fusbh200_qtd *fusbh200_qtd_alloc (struct fusbh200_hcd *fusbh200, gfp_t flags)
+{
+	struct fusbh200_qtd		*qtd;
+	dma_addr_t		dma;
+
+	qtd = dma_pool_alloc (fusbh200->qtd_pool, flags, &dma);
+	if (qtd != NULL) {
+		fusbh200_qtd_init(fusbh200, qtd, dma);
+	}
+	return qtd;
+}
+
+static inline void fusbh200_qtd_free (struct fusbh200_hcd *fusbh200, struct fusbh200_qtd *qtd)
+{
+	dma_pool_free (fusbh200->qtd_pool, qtd, qtd->qtd_dma);
+}
+
+
+static void qh_destroy(struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{
+	/* clean qtds first, and know this is not linked */
+	if (!list_empty (&qh->qtd_list) || qh->qh_next.ptr) {
+		fusbh200_dbg (fusbh200, "unused qh not empty!\n");
+		BUG ();
+	}
+	if (qh->dummy)
+		fusbh200_qtd_free (fusbh200, qh->dummy);
+	dma_pool_free(fusbh200->qh_pool, qh->hw, qh->qh_dma);
+	kfree(qh);
+}
+
+static struct fusbh200_qh *fusbh200_qh_alloc (struct fusbh200_hcd *fusbh200, gfp_t flags)
+{
+	struct fusbh200_qh		*qh;
+	dma_addr_t		dma;
+
+	qh = kzalloc(sizeof *qh, GFP_ATOMIC);
+	if (!qh)
+		goto done;
+	qh->hw = (struct fusbh200_qh_hw *)
+		dma_pool_alloc(fusbh200->qh_pool, flags, &dma);
+	if (!qh->hw)
+		goto fail;
+	memset(qh->hw, 0, sizeof *qh->hw);
+	qh->qh_dma = dma;
+	// INIT_LIST_HEAD (&qh->qh_list);
+	INIT_LIST_HEAD (&qh->qtd_list);
+
+	/* dummy td enables safe urb queuing */
+	qh->dummy = fusbh200_qtd_alloc (fusbh200, flags);
+	if (qh->dummy == NULL) {
+		fusbh200_dbg (fusbh200, "no dummy td\n");
+		goto fail1;
+	}
+done:
+	return qh;
+fail1:
+	dma_pool_free(fusbh200->qh_pool, qh->hw, qh->qh_dma);
+fail:
+	kfree(qh);
+	return NULL;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* The queue heads and transfer descriptors are managed from pools tied
+ * to each of the "per device" structures.
+ * This is the initialisation and cleanup code.
+ */
+
+static void fusbh200_mem_cleanup (struct fusbh200_hcd *fusbh200)
+{
+	if (fusbh200->async)
+		qh_destroy(fusbh200, fusbh200->async);
+	fusbh200->async = NULL;
+
+	if (fusbh200->dummy)
+		qh_destroy(fusbh200, fusbh200->dummy);
+	fusbh200->dummy = NULL;
+
+	/* DMA consistent memory and pools */
+	if (fusbh200->qtd_pool)
+		dma_pool_destroy (fusbh200->qtd_pool);
+	fusbh200->qtd_pool = NULL;
+
+	if (fusbh200->qh_pool) {
+		dma_pool_destroy (fusbh200->qh_pool);
+		fusbh200->qh_pool = NULL;
+	}
+
+	if (fusbh200->itd_pool)
+		dma_pool_destroy (fusbh200->itd_pool);
+	fusbh200->itd_pool = NULL;
+
+	if (fusbh200->periodic)
+		dma_free_coherent (fusbh200_to_hcd(fusbh200)->self.controller,
+			fusbh200->periodic_size * sizeof (u32),
+			fusbh200->periodic, fusbh200->periodic_dma);
+	fusbh200->periodic = NULL;
+
+	/* shadow periodic table */
+	kfree(fusbh200->pshadow);
+	fusbh200->pshadow = NULL;
+}
+
+/* remember to add cleanup code (above) if you add anything here */
+static int fusbh200_mem_init (struct fusbh200_hcd *fusbh200, gfp_t flags)
+{
+	int i;
+
+	/* QTDs for control/bulk/intr transfers */
+	fusbh200->qtd_pool = dma_pool_create ("fusbh200_qtd",
+			fusbh200_to_hcd(fusbh200)->self.controller,
+			sizeof (struct fusbh200_qtd),
+			32 /* byte alignment (for hw parts) */,
+			4096 /* can't cross 4K */);
+	if (!fusbh200->qtd_pool) {
+		goto fail;
+	}
+
+	/* QHs for control/bulk/intr transfers */
+	fusbh200->qh_pool = dma_pool_create ("fusbh200_qh",
+			fusbh200_to_hcd(fusbh200)->self.controller,
+			sizeof(struct fusbh200_qh_hw),
+			32 /* byte alignment (for hw parts) */,
+			4096 /* can't cross 4K */);
+	if (!fusbh200->qh_pool) {
+		goto fail;
+	}
+	fusbh200->async = fusbh200_qh_alloc (fusbh200, flags);
+	if (!fusbh200->async) {
+		goto fail;
+	}
+
+	/* ITD for high speed ISO transfers */
+	fusbh200->itd_pool = dma_pool_create ("fusbh200_itd",
+			fusbh200_to_hcd(fusbh200)->self.controller,
+			sizeof (struct fusbh200_itd),
+			64 /* byte alignment (for hw parts) */,
+			4096 /* can't cross 4K */);
+	if (!fusbh200->itd_pool) {
+		goto fail;
+	}
+
+	/* Hardware periodic table */
+	fusbh200->periodic = (__le32 *)
+		dma_alloc_coherent (fusbh200_to_hcd(fusbh200)->self.controller,
+			fusbh200->periodic_size * sizeof(__le32),
+			&fusbh200->periodic_dma, 0);
+	if (fusbh200->periodic == NULL) {
+		goto fail;
+	}
+
+		for (i = 0; i < fusbh200->periodic_size; i++)
+			fusbh200->periodic[i] = FUSBH200_LIST_END(fusbh200);
+
+	/* software shadow of hardware table */
+	fusbh200->pshadow = kcalloc(fusbh200->periodic_size, sizeof(void *), flags);
+	if (fusbh200->pshadow != NULL)
+		return 0;
+
+fail:
+	fusbh200_dbg (fusbh200, "couldn't init memory\n");
+	fusbh200_mem_cleanup (fusbh200);
+	return -ENOMEM;
+}
+/*-------------------------------------------------------------------------*/
+/*
+ * EHCI hardware queue manipulation ... the core.  QH/QTD manipulation.
+ *
+ * Control, bulk, and interrupt traffic all use "qh" lists.  They list "qtd"
+ * entries describing USB transactions, max 16-20kB/entry (with 4kB-aligned
+ * buffers needed for the larger number).  We use one QH per endpoint, queue
+ * multiple urbs (all three types) per endpoint.  URBs may need several qtds.
+ *
+ * ISO traffic uses "ISO TD" (itd) records, and (along with
+ * interrupts) needs careful scheduling.  Performance improvements can be
+ * an ongoing challenge.  That's in "ehci-sched.c".
+ *
+ * USB 1.1 devices are handled (a) by "companion" OHCI or UHCI root hubs,
+ * or otherwise through transaction translators (TTs) in USB 2.0 hubs using
+ * (b) special fields in qh entries or (c) split iso entries.  TTs will
+ * buffer low/full speed data so the host collects it at high speed.
+ */
+
+/*-------------------------------------------------------------------------*/
+
+/* fill a qtd, returning how much of the buffer we were able to queue up */
+
+static int
+qtd_fill(struct fusbh200_hcd *fusbh200, struct fusbh200_qtd *qtd, dma_addr_t buf,
+		  size_t len, int token, int maxpacket)
+{
+	int	i, count;
+	u64	addr = buf;
+
+	/* one buffer entry per 4K ... first might be short or unaligned */
+	qtd->hw_buf[0] = cpu_to_hc32(fusbh200, (u32)addr);
+	qtd->hw_buf_hi[0] = cpu_to_hc32(fusbh200, (u32)(addr >> 32));
+	count = 0x1000 - (buf & 0x0fff);	/* rest of that page */
+	if (likely (len < count))		/* ... iff needed */
+		count = len;
+	else {
+		buf +=  0x1000;
+		buf &= ~0x0fff;
+
+		/* per-qtd limit: from 16K to 20K (best alignment) */
+		for (i = 1; count < len && i < 5; i++) {
+			addr = buf;
+			qtd->hw_buf[i] = cpu_to_hc32(fusbh200, (u32)addr);
+			qtd->hw_buf_hi[i] = cpu_to_hc32(fusbh200,
+					(u32)(addr >> 32));
+			buf += 0x1000;
+			if ((count + 0x1000) < len)
+				count += 0x1000;
+			else
+				count = len;
+		}
+
+		/* short packets may only terminate transfers */
+		if (count != len)
+			count -= (count % maxpacket);
+	}
+	qtd->hw_token = cpu_to_hc32(fusbh200, (count << 16) | token);
+	qtd->length = count;
+
+	return count;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static inline void
+qh_update (struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh, struct fusbh200_qtd *qtd)
+{
+	struct fusbh200_qh_hw *hw = qh->hw;
+
+	/* writes to an active overlay are unsafe */
+	BUG_ON(qh->qh_state != QH_STATE_IDLE);
+
+	hw->hw_qtd_next = QTD_NEXT(fusbh200, qtd->qtd_dma);
+	hw->hw_alt_next = FUSBH200_LIST_END(fusbh200);
+
+	/* Except for control endpoints, we make hardware maintain data
+	 * toggle (like OHCI) ... here (re)initialize the toggle in the QH,
+	 * and set the pseudo-toggle in udev. Only usb_clear_halt() will
+	 * ever clear it.
+	 */
+	if (!(hw->hw_info1 & cpu_to_hc32(fusbh200, QH_TOGGLE_CTL))) {
+		unsigned	is_out, epnum;
+
+		is_out = qh->is_out;
+		epnum = (hc32_to_cpup(fusbh200, &hw->hw_info1) >> 8) & 0x0f;
+		if (unlikely (!usb_gettoggle (qh->dev, epnum, is_out))) {
+			hw->hw_token &= ~cpu_to_hc32(fusbh200, QTD_TOGGLE);
+			usb_settoggle (qh->dev, epnum, is_out, 1);
+		}
+	}
+
+	hw->hw_token &= cpu_to_hc32(fusbh200, QTD_TOGGLE | QTD_STS_PING);
+}
+
+/* if it weren't for a common silicon quirk (writing the dummy into the qh
+ * overlay, so qh->hw_token wrongly becomes inactive/halted), only fault
+ * recovery (including urb dequeue) would need software changes to a QH...
+ */
+static void
+qh_refresh (struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{
+	struct fusbh200_qtd *qtd;
+
+	if (list_empty (&qh->qtd_list))
+		qtd = qh->dummy;
+	else {
+		qtd = list_entry (qh->qtd_list.next,
+				struct fusbh200_qtd, qtd_list);
+		/*
+		 * first qtd may already be partially processed.
+		 * If we come here during unlink, the QH overlay region
+		 * might have reference to the just unlinked qtd. The
+		 * qtd is updated in qh_completions(). Update the QH
+		 * overlay here.
+		 */
+		if (cpu_to_hc32(fusbh200, qtd->qtd_dma) == qh->hw->hw_current) {
+			qh->hw->hw_qtd_next = qtd->hw_next;
+			qtd = NULL;
+		}
+	}
+
+	if (qtd)
+		qh_update (fusbh200, qh, qtd);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void qh_link_async(struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh);
+
+static void fusbh200_clear_tt_buffer_complete(struct usb_hcd *hcd,
+		struct usb_host_endpoint *ep)
+{
+	struct fusbh200_hcd		*fusbh200 = hcd_to_fusbh200(hcd);
+	struct fusbh200_qh		*qh = ep->hcpriv;
+	unsigned long		flags;
+
+	spin_lock_irqsave(&fusbh200->lock, flags);
+	qh->clearing_tt = 0;
+	if (qh->qh_state == QH_STATE_IDLE && !list_empty(&qh->qtd_list)
+			&& fusbh200->rh_state == FUSBH200_RH_RUNNING)
+		qh_link_async(fusbh200, qh);
+	spin_unlock_irqrestore(&fusbh200->lock, flags);
+}
+
+static void fusbh200_clear_tt_buffer(struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh,
+		struct urb *urb, u32 token)
+{
+
+	/* If an async split transaction gets an error or is unlinked,
+	 * the TT buffer may be left in an indeterminate state.  We
+	 * have to clear the TT buffer.
+	 *
+	 * Note: this routine is never called for Isochronous transfers.
+	 */
+	if (urb->dev->tt && !usb_pipeint(urb->pipe) && !qh->clearing_tt) {
+#ifdef DEBUG
+		struct usb_device *tt = urb->dev->tt->hub;
+		dev_dbg(&tt->dev,
+			"clear tt buffer port %d, a%d ep%d t%08x\n",
+			urb->dev->ttport, urb->dev->devnum,
+			usb_pipeendpoint(urb->pipe), token);
+#endif /* DEBUG */
+		if (urb->dev->tt->hub !=
+		    fusbh200_to_hcd(fusbh200)->self.root_hub) {
+			if (usb_hub_clear_tt_buffer(urb) == 0)
+				qh->clearing_tt = 1;
+		}
+	}
+}
+
+static int qtd_copy_status (
+	struct fusbh200_hcd *fusbh200,
+	struct urb *urb,
+	size_t length,
+	u32 token
+)
+{
+	int	status = -EINPROGRESS;
+
+	/* count IN/OUT bytes, not SETUP (even short packets) */
+	if (likely (QTD_PID (token) != 2))
+		urb->actual_length += length - QTD_LENGTH (token);
+
+	/* don't modify error codes */
+	if (unlikely(urb->unlinked))
+		return status;
+
+	/* force cleanup after short read; not always an error */
+	if (unlikely (IS_SHORT_READ (token)))
+		status = -EREMOTEIO;
+
+	/* serious "can't proceed" faults reported by the hardware */
+	if (token & QTD_STS_HALT) {
+		if (token & QTD_STS_BABBLE) {
+			/* FIXME "must" disable babbling device's port too */
+			status = -EOVERFLOW;
+		/* CERR nonzero + halt --> stall */
+		} else if (QTD_CERR(token)) {
+			status = -EPIPE;
+
+		/* In theory, more than one of the following bits can be set
+		 * since they are sticky and the transaction is retried.
+		 * Which to test first is rather arbitrary.
+		 */
+		} else if (token & QTD_STS_MMF) {
+			/* fs/ls interrupt xfer missed the complete-split */
+			status = -EPROTO;
+		} else if (token & QTD_STS_DBE) {
+			status = (QTD_PID (token) == 1) /* IN ? */
+				? -ENOSR  /* hc couldn't read data */
+				: -ECOMM; /* hc couldn't write data */
+		} else if (token & QTD_STS_XACT) {
+			/* timeout, bad CRC, wrong PID, etc */
+			fusbh200_dbg(fusbh200, "devpath %s ep%d%s 3strikes\n",
+				urb->dev->devpath,
+				usb_pipeendpoint(urb->pipe),
+				usb_pipein(urb->pipe) ? "in" : "out");
+			status = -EPROTO;
+		} else {	/* unknown */
+			status = -EPROTO;
+		}
+
+		fusbh200_vdbg (fusbh200,
+			"dev%d ep%d%s qtd token %08x --> status %d\n",
+			usb_pipedevice (urb->pipe),
+			usb_pipeendpoint (urb->pipe),
+			usb_pipein (urb->pipe) ? "in" : "out",
+			token, status);
+	}
+
+	return status;
+}
+
+static void
+fusbh200_urb_done(struct fusbh200_hcd *fusbh200, struct urb *urb, int status)
+__releases(fusbh200->lock)
+__acquires(fusbh200->lock)
+{
+	if (likely (urb->hcpriv != NULL)) {
+		struct fusbh200_qh	*qh = (struct fusbh200_qh *) urb->hcpriv;
+
+		/* S-mask in a QH means it's an interrupt urb */
+		if ((qh->hw->hw_info2 & cpu_to_hc32(fusbh200, QH_SMASK)) != 0) {
+
+			/* ... update hc-wide periodic stats (for usbfs) */
+			fusbh200_to_hcd(fusbh200)->self.bandwidth_int_reqs--;
+		}
+	}
+
+	if (unlikely(urb->unlinked)) {
+		COUNT(fusbh200->stats.unlink);
+	} else {
+		/* report non-error and short read status as zero */
+		if (status == -EINPROGRESS || status == -EREMOTEIO)
+			status = 0;
+		COUNT(fusbh200->stats.complete);
+	}
+
+#ifdef FUSBH200_URB_TRACE
+	fusbh200_dbg (fusbh200,
+		"%s %s urb %p ep%d%s status %d len %d/%d\n",
+		__func__, urb->dev->devpath, urb,
+		usb_pipeendpoint (urb->pipe),
+		usb_pipein (urb->pipe) ? "in" : "out",
+		status,
+		urb->actual_length, urb->transfer_buffer_length);
+#endif
+
+	/* complete() can reenter this HCD */
+	usb_hcd_unlink_urb_from_ep(fusbh200_to_hcd(fusbh200), urb);
+	spin_unlock (&fusbh200->lock);
+	usb_hcd_giveback_urb(fusbh200_to_hcd(fusbh200), urb, status);
+	spin_lock (&fusbh200->lock);
+}
+
+static int qh_schedule (struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh);
+
+/*
+ * Process and free completed qtds for a qh, returning URBs to drivers.
+ * Chases up to qh->hw_current.  Returns number of completions called,
+ * indicating how much "real" work we did.
+ */
+static unsigned
+qh_completions (struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{
+	struct fusbh200_qtd		*last, *end = qh->dummy;
+	struct list_head	*entry, *tmp;
+	int			last_status;
+	int			stopped;
+	unsigned		count = 0;
+	u8			state;
+	struct fusbh200_qh_hw	*hw = qh->hw;
+
+	if (unlikely (list_empty (&qh->qtd_list)))
+		return count;
+
+	/* completions (or tasks on other cpus) must never clobber HALT
+	 * till we've gone through and cleaned everything up, even when
+	 * they add urbs to this qh's queue or mark them for unlinking.
+	 *
+	 * NOTE:  unlinking expects to be done in queue order.
+	 *
+	 * It's a bug for qh->qh_state to be anything other than
+	 * QH_STATE_IDLE, unless our caller is scan_async() or
+	 * scan_intr().
+	 */
+	state = qh->qh_state;
+	qh->qh_state = QH_STATE_COMPLETING;
+	stopped = (state == QH_STATE_IDLE);
+
+ rescan:
+	last = NULL;
+	last_status = -EINPROGRESS;
+	qh->needs_rescan = 0;
+
+	/* remove de-activated QTDs from front of queue.
+	 * after faults (including short reads), cleanup this urb
+	 * then let the queue advance.
+	 * if queue is stopped, handles unlinks.
+	 */
+	list_for_each_safe (entry, tmp, &qh->qtd_list) {
+		struct fusbh200_qtd	*qtd;
+		struct urb	*urb;
+		u32		token = 0;
+
+		qtd = list_entry (entry, struct fusbh200_qtd, qtd_list);
+		urb = qtd->urb;
+
+		/* clean up any state from previous QTD ...*/
+		if (last) {
+			if (likely (last->urb != urb)) {
+				fusbh200_urb_done(fusbh200, last->urb, last_status);
+				count++;
+				last_status = -EINPROGRESS;
+			}
+			fusbh200_qtd_free (fusbh200, last);
+			last = NULL;
+		}
+
+		/* ignore urbs submitted during completions we reported */
+		if (qtd == end)
+			break;
+
+		/* hardware copies qtd out of qh overlay */
+		rmb ();
+		token = hc32_to_cpu(fusbh200, qtd->hw_token);
+
+		/* always clean up qtds the hc de-activated */
+ retry_xacterr:
+		if ((token & QTD_STS_ACTIVE) == 0) {
+
+			/* Report Data Buffer Error: non-fatal but useful */
+			if (token & QTD_STS_DBE)
+				fusbh200_dbg(fusbh200,
+					"detected DataBufferErr for urb %p ep%d%s len %d, qtd %p [qh %p]\n",
+					urb,
+					usb_endpoint_num(&urb->ep->desc),
+					usb_endpoint_dir_in(&urb->ep->desc) ? "in" : "out",
+					urb->transfer_buffer_length,
+					qtd,
+					qh);
+
+			/* on STALL, error, and short reads this urb must
+			 * complete and all its qtds must be recycled.
+			 */
+			if ((token & QTD_STS_HALT) != 0) {
+
+				/* retry transaction errors until we
+				 * reach the software xacterr limit
+				 */
+				if ((token & QTD_STS_XACT) &&
+						QTD_CERR(token) == 0 &&
+						++qh->xacterrs < QH_XACTERR_MAX &&
+						!urb->unlinked) {
+					fusbh200_dbg(fusbh200,
+	"detected XactErr len %zu/%zu retry %d\n",
+	qtd->length - QTD_LENGTH(token), qtd->length, qh->xacterrs);
+
+					/* reset the token in the qtd and the
+					 * qh overlay (which still contains
+					 * the qtd) so that we pick up from
+					 * where we left off
+					 */
+					token &= ~QTD_STS_HALT;
+					token |= QTD_STS_ACTIVE |
+							(FUSBH200_TUNE_CERR << 10);
+					qtd->hw_token = cpu_to_hc32(fusbh200,
+							token);
+					wmb();
+					hw->hw_token = cpu_to_hc32(fusbh200,
+							token);
+					goto retry_xacterr;
+				}
+				stopped = 1;
+
+			/* magic dummy for some short reads; qh won't advance.
+			 * that silicon quirk can kick in with this dummy too.
+			 *
+			 * other short reads won't stop the queue, including
+			 * control transfers (status stage handles that) or
+			 * most other single-qtd reads ... the queue stops if
+			 * URB_SHORT_NOT_OK was set so the driver submitting
+			 * the urbs could clean it up.
+			 */
+			} else if (IS_SHORT_READ (token)
+					&& !(qtd->hw_alt_next
+						& FUSBH200_LIST_END(fusbh200))) {
+				stopped = 1;
+			}
+
+		/* stop scanning when we reach qtds the hc is using */
+		} else if (likely (!stopped
+				&& fusbh200->rh_state >= FUSBH200_RH_RUNNING)) {
+			break;
+
+		/* scan the whole queue for unlinks whenever it stops */
+		} else {
+			stopped = 1;
+
+			/* cancel everything if we halt, suspend, etc */
+			if (fusbh200->rh_state < FUSBH200_RH_RUNNING)
+				last_status = -ESHUTDOWN;
+
+			/* this qtd is active; skip it unless a previous qtd
+			 * for its urb faulted, or its urb was canceled.
+			 */
+			else if (last_status == -EINPROGRESS && !urb->unlinked)
+				continue;
+
+			/* qh unlinked; token in overlay may be most current */
+			if (state == QH_STATE_IDLE
+					&& cpu_to_hc32(fusbh200, qtd->qtd_dma)
+						== hw->hw_current) {
+				token = hc32_to_cpu(fusbh200, hw->hw_token);
+
+				/* An unlink may leave an incomplete
+				 * async transaction in the TT buffer.
+				 * We have to clear it.
+				 */
+				fusbh200_clear_tt_buffer(fusbh200, qh, urb, token);
+			}
+		}
+
+		/* unless we already know the urb's status, collect qtd status
+		 * and update count of bytes transferred.  in common short read
+		 * cases with only one data qtd (including control transfers),
+		 * queue processing won't halt.  but with two or more qtds (for
+		 * example, with a 32 KB transfer), when the first qtd gets a
+		 * short read the second must be removed by hand.
+		 */
+		if (last_status == -EINPROGRESS) {
+			last_status = qtd_copy_status(fusbh200, urb,
+					qtd->length, token);
+			if (last_status == -EREMOTEIO
+					&& (qtd->hw_alt_next
+						& FUSBH200_LIST_END(fusbh200)))
+				last_status = -EINPROGRESS;
+
+			/* As part of low/full-speed endpoint-halt processing
+			 * we must clear the TT buffer (11.17.5).
+			 */
+			if (unlikely(last_status != -EINPROGRESS &&
+					last_status != -EREMOTEIO)) {
+				/* The TT's in some hubs malfunction when they
+				 * receive this request following a STALL (they
+				 * stop sending isochronous packets).  Since a
+				 * STALL can't leave the TT buffer in a busy
+				 * state (if you believe Figures 11-48 - 11-51
+				 * in the USB 2.0 spec), we won't clear the TT
+				 * buffer in this case.  Strictly speaking this
+				 * is a violation of the spec.
+				 */
+				if (last_status != -EPIPE)
+					fusbh200_clear_tt_buffer(fusbh200, qh, urb,
+							token);
+			}
+		}
+
+		/* if we're removing something not at the queue head,
+		 * patch the hardware queue pointer.
+		 */
+		if (stopped && qtd->qtd_list.prev != &qh->qtd_list) {
+			last = list_entry (qtd->qtd_list.prev,
+					struct fusbh200_qtd, qtd_list);
+			last->hw_next = qtd->hw_next;
+		}
+
+		/* remove qtd; it's recycled after possible urb completion */
+		list_del (&qtd->qtd_list);
+		last = qtd;
+
+		/* reinit the xacterr counter for the next qtd */
+		qh->xacterrs = 0;
+	}
+
+	/* last urb's completion might still need calling */
+	if (likely (last != NULL)) {
+		fusbh200_urb_done(fusbh200, last->urb, last_status);
+		count++;
+		fusbh200_qtd_free (fusbh200, last);
+	}
+
+	/* Do we need to rescan for URBs dequeued during a giveback? */
+	if (unlikely(qh->needs_rescan)) {
+		/* If the QH is already unlinked, do the rescan now. */
+		if (state == QH_STATE_IDLE)
+			goto rescan;
+
+		/* Otherwise we have to wait until the QH is fully unlinked.
+		 * Our caller will start an unlink if qh->needs_rescan is
+		 * set.  But if an unlink has already started, nothing needs
+		 * to be done.
+		 */
+		if (state != QH_STATE_LINKED)
+			qh->needs_rescan = 0;
+	}
+
+	/* restore original state; caller must unlink or relink */
+	qh->qh_state = state;
+
+	/* be sure the hardware's done with the qh before refreshing
+	 * it after fault cleanup, or recovering from silicon wrongly
+	 * overlaying the dummy qtd (which reduces DMA chatter).
+	 */
+	if (stopped != 0 || hw->hw_qtd_next == FUSBH200_LIST_END(fusbh200)) {
+		switch (state) {
+		case QH_STATE_IDLE:
+			qh_refresh(fusbh200, qh);
+			break;
+		case QH_STATE_LINKED:
+			/* We won't refresh a QH that's linked (after the HC
+			 * stopped the queue).  That avoids a race:
+			 *  - HC reads first part of QH;
+			 *  - CPU updates that first part and the token;
+			 *  - HC reads rest of that QH, including token
+			 * Result:  HC gets an inconsistent image, and then
+			 * DMAs to/from the wrong memory (corrupting it).
+			 *
+			 * That should be rare for interrupt transfers,
+			 * except maybe high bandwidth ...
+			 */
+
+			/* Tell the caller to start an unlink */
+			qh->needs_rescan = 1;
+			break;
+		/* otherwise, unlink already started */
+		}
+	}
+
+	return count;
+}
+
+/*-------------------------------------------------------------------------*/
+
+// high bandwidth multiplier, as encoded in highspeed endpoint descriptors
+#define hb_mult(wMaxPacketSize) (1 + (((wMaxPacketSize) >> 11) & 0x03))
+// ... and packet size, for any kind of endpoint descriptor
+#define max_packet(wMaxPacketSize) ((wMaxPacketSize) & 0x07ff)
+
+/*
+ * reverse of qh_urb_transaction:  free a list of TDs.
+ * used for cleanup after errors, before HC sees an URB's TDs.
+ */
+static void qtd_list_free (
+	struct fusbh200_hcd		*fusbh200,
+	struct urb		*urb,
+	struct list_head	*qtd_list
+) {
+	struct list_head	*entry, *temp;
+
+	list_for_each_safe (entry, temp, qtd_list) {
+		struct fusbh200_qtd	*qtd;
+
+		qtd = list_entry (entry, struct fusbh200_qtd, qtd_list);
+		list_del (&qtd->qtd_list);
+		fusbh200_qtd_free (fusbh200, qtd);
+	}
+}
+
+/*
+ * create a list of filled qtds for this URB; won't link into qh.
+ */
+static struct list_head *
+qh_urb_transaction (
+	struct fusbh200_hcd		*fusbh200,
+	struct urb		*urb,
+	struct list_head	*head,
+	gfp_t			flags
+) {
+	struct fusbh200_qtd		*qtd, *qtd_prev;
+	dma_addr_t		buf;
+	int			len, this_sg_len, maxpacket;
+	int			is_input;
+	u32			token;
+	int			i;
+	struct scatterlist	*sg;
+
+	/*
+	 * URBs map to sequences of QTDs:  one logical transaction
+	 */
+	qtd = fusbh200_qtd_alloc (fusbh200, flags);
+	if (unlikely (!qtd))
+		return NULL;
+	list_add_tail (&qtd->qtd_list, head);
+	qtd->urb = urb;
+
+	token = QTD_STS_ACTIVE;
+	token |= (FUSBH200_TUNE_CERR << 10);
+	/* for split transactions, SplitXState initialized to zero */
+
+	len = urb->transfer_buffer_length;
+	is_input = usb_pipein (urb->pipe);
+	if (usb_pipecontrol (urb->pipe)) {
+		/* SETUP pid */
+		qtd_fill(fusbh200, qtd, urb->setup_dma,
+				sizeof (struct usb_ctrlrequest),
+				token | (2 /* "setup" */ << 8), 8);
+
+		/* ... and always at least one more pid */
+		token ^= QTD_TOGGLE;
+		qtd_prev = qtd;
+		qtd = fusbh200_qtd_alloc (fusbh200, flags);
+		if (unlikely (!qtd))
+			goto cleanup;
+		qtd->urb = urb;
+		qtd_prev->hw_next = QTD_NEXT(fusbh200, qtd->qtd_dma);
+		list_add_tail (&qtd->qtd_list, head);
+
+		/* for zero length DATA stages, STATUS is always IN */
+		if (len == 0)
+			token |= (1 /* "in" */ << 8);
+	}
+
+	/*
+	 * data transfer stage:  buffer setup
+	 */
+	i = urb->num_mapped_sgs;
+	if (len > 0 && i > 0) {
+		sg = urb->sg;
+		buf = sg_dma_address(sg);
+
+		/* urb->transfer_buffer_length may be smaller than the
+		 * size of the scatterlist (or vice versa)
+		 */
+		this_sg_len = min_t(int, sg_dma_len(sg), len);
+	} else {
+		sg = NULL;
+		buf = urb->transfer_dma;
+		this_sg_len = len;
+	}
+
+	if (is_input)
+		token |= (1 /* "in" */ << 8);
+	/* else it's already initted to "out" pid (0 << 8) */
+
+	maxpacket = max_packet(usb_maxpacket(urb->dev, urb->pipe, !is_input));
+
+	/*
+	 * buffer gets wrapped in one or more qtds;
+	 * last one may be "short" (including zero len)
+	 * and may serve as a control status ack
+	 */
+	for (;;) {
+		int this_qtd_len;
+
+		this_qtd_len = qtd_fill(fusbh200, qtd, buf, this_sg_len, token,
+				maxpacket);
+		this_sg_len -= this_qtd_len;
+		len -= this_qtd_len;
+		buf += this_qtd_len;
+
+		/*
+		 * short reads advance to a "magic" dummy instead of the next
+		 * qtd ... that forces the queue to stop, for manual cleanup.
+		 * (this will usually be overridden later.)
+		 */
+		if (is_input)
+			qtd->hw_alt_next = fusbh200->async->hw->hw_alt_next;
+
+		/* qh makes control packets use qtd toggle; maybe switch it */
+		if ((maxpacket & (this_qtd_len + (maxpacket - 1))) == 0)
+			token ^= QTD_TOGGLE;
+
+		if (likely(this_sg_len <= 0)) {
+			if (--i <= 0 || len <= 0)
+				break;
+			sg = sg_next(sg);
+			buf = sg_dma_address(sg);
+			this_sg_len = min_t(int, sg_dma_len(sg), len);
+		}
+
+		qtd_prev = qtd;
+		qtd = fusbh200_qtd_alloc (fusbh200, flags);
+		if (unlikely (!qtd))
+			goto cleanup;
+		qtd->urb = urb;
+		qtd_prev->hw_next = QTD_NEXT(fusbh200, qtd->qtd_dma);
+		list_add_tail (&qtd->qtd_list, head);
+	}
+
+	/*
+	 * unless the caller requires manual cleanup after short reads,
+	 * have the alt_next mechanism keep the queue running after the
+	 * last data qtd (the only one, for control and most other cases).
+	 */
+	if (likely ((urb->transfer_flags & URB_SHORT_NOT_OK) == 0
+				|| usb_pipecontrol (urb->pipe)))
+		qtd->hw_alt_next = FUSBH200_LIST_END(fusbh200);
+
+	/*
+	 * control requests may need a terminating data "status" ack;
+	 * other OUT ones may need a terminating short packet
+	 * (zero length).
+	 */
+	if (likely (urb->transfer_buffer_length != 0)) {
+		int	one_more = 0;
+
+		if (usb_pipecontrol (urb->pipe)) {
+			one_more = 1;
+			token ^= 0x0100;	/* "in" <--> "out"  */
+			token |= QTD_TOGGLE;	/* force DATA1 */
+		} else if (usb_pipeout(urb->pipe)
+				&& (urb->transfer_flags & URB_ZERO_PACKET)
+				&& !(urb->transfer_buffer_length % maxpacket)) {
+			one_more = 1;
+		}
+		if (one_more) {
+			qtd_prev = qtd;
+			qtd = fusbh200_qtd_alloc (fusbh200, flags);
+			if (unlikely (!qtd))
+				goto cleanup;
+			qtd->urb = urb;
+			qtd_prev->hw_next = QTD_NEXT(fusbh200, qtd->qtd_dma);
+			list_add_tail (&qtd->qtd_list, head);
+
+			/* never any data in such packets */
+			qtd_fill(fusbh200, qtd, 0, 0, token, 0);
+		}
+	}
+
+	/* by default, enable interrupt on urb completion */
+	if (likely (!(urb->transfer_flags & URB_NO_INTERRUPT)))
+		qtd->hw_token |= cpu_to_hc32(fusbh200, QTD_IOC);
+	return head;
+
+cleanup:
+	qtd_list_free (fusbh200, urb, head);
+	return NULL;
+}
+
+/*-------------------------------------------------------------------------*/
+
+// Would be best to create all qh's from config descriptors,
+// when each interface/altsetting is established.  Unlink
+// any previous qh and cancel its urbs first; endpoints are
+// implicitly reset then (data toggle too).
+// That'd mean updating how usbcore talks to HCDs. (2.7?)
+
+
+/*
+ * Each QH holds a qtd list; a QH is used for everything except iso.
+ *
+ * For interrupt urbs, the scheduler must set the microframe scheduling
+ * mask(s) each time the QH gets scheduled.  For highspeed, that's
+ * just one microframe in the s-mask.  For split interrupt transactions
+ * there are additional complications: c-mask, maybe FSTNs.
+ */
+static struct fusbh200_qh *
+qh_make (
+	struct fusbh200_hcd		*fusbh200,
+	struct urb		*urb,
+	gfp_t			flags
+) {
+	struct fusbh200_qh		*qh = fusbh200_qh_alloc (fusbh200, flags);
+	u32			info1 = 0, info2 = 0;
+	int			is_input, type;
+	int			maxp = 0;
+	struct usb_tt		*tt = urb->dev->tt;
+	struct fusbh200_qh_hw	*hw;
+
+	if (!qh)
+		return qh;
+
+	/*
+	 * init endpoint/device data for this QH
+	 */
+	info1 |= usb_pipeendpoint (urb->pipe) << 8;
+	info1 |= usb_pipedevice (urb->pipe) << 0;
+
+	is_input = usb_pipein (urb->pipe);
+	type = usb_pipetype (urb->pipe);
+	maxp = usb_maxpacket (urb->dev, urb->pipe, !is_input);
+
+	/* 1024 byte maxpacket is a hardware ceiling.  High bandwidth
+	 * acts like up to 3KB, but is built from smaller packets.
+	 */
+	if (max_packet(maxp) > 1024) {
+		fusbh200_dbg(fusbh200, "bogus qh maxpacket %d\n", max_packet(maxp));
+		goto done;
+	}
+
+	/* Compute interrupt scheduling parameters just once, and save.
+	 * - allowing for high bandwidth, how many nsec/uframe are used?
+	 * - split transactions need a second CSPLIT uframe; same question
+	 * - splits also need a schedule gap (for full/low speed I/O)
+	 * - qh has a polling interval
+	 *
+	 * For control/bulk requests, the HC or TT handles these.
+	 */
+	if (type == PIPE_INTERRUPT) {
+		qh->usecs = NS_TO_US(usb_calc_bus_time(USB_SPEED_HIGH,
+				is_input, 0,
+				hb_mult(maxp) * max_packet(maxp)));
+		qh->start = NO_FRAME;
+
+		if (urb->dev->speed == USB_SPEED_HIGH) {
+			qh->c_usecs = 0;
+			qh->gap_uf = 0;
+
+			qh->period = urb->interval >> 3;
+			if (qh->period == 0 && urb->interval != 1) {
+				/* NOTE interval 2 or 4 uframes could work.
+				 * But interval 1 scheduling is simpler, and
+				 * includes high bandwidth.
+				 */
+				urb->interval = 1;
+			} else if (qh->period > fusbh200->periodic_size) {
+				qh->period = fusbh200->periodic_size;
+				urb->interval = qh->period << 3;
+			}
+		} else {
+			int		think_time;
+
+			/* gap is f(FS/LS transfer times) */
+			qh->gap_uf = 1 + usb_calc_bus_time (urb->dev->speed,
+					is_input, 0, maxp) / (125 * 1000);
+
+			/* FIXME this just approximates SPLIT/CSPLIT times */
+			if (is_input) {		// SPLIT, gap, CSPLIT+DATA
+				qh->c_usecs = qh->usecs + HS_USECS (0);
+				qh->usecs = HS_USECS (1);
+			} else {		// SPLIT+DATA, gap, CSPLIT
+				qh->usecs += HS_USECS (1);
+				qh->c_usecs = HS_USECS (0);
+			}
+
+			think_time = tt ? tt->think_time : 0;
+			qh->tt_usecs = NS_TO_US (think_time +
+					usb_calc_bus_time (urb->dev->speed,
+					is_input, 0, max_packet (maxp)));
+			qh->period = urb->interval;
+			if (qh->period > fusbh200->periodic_size) {
+				qh->period = fusbh200->periodic_size;
+				urb->interval = qh->period;
+			}
+		}
+	}
+
+	/* support for tt scheduling, and access to toggles */
+	qh->dev = urb->dev;
+
+	/* using TT? */
+	switch (urb->dev->speed) {
+	case USB_SPEED_LOW:
+		info1 |= QH_LOW_SPEED;
+		/* FALL THROUGH */
+
+	case USB_SPEED_FULL:
+		/* EPS 0 means "full" */
+		if (type != PIPE_INTERRUPT)
+			info1 |= (FUSBH200_TUNE_RL_TT << 28);
+		if (type == PIPE_CONTROL) {
+			info1 |= QH_CONTROL_EP;		/* for TT */
+			info1 |= QH_TOGGLE_CTL;		/* toggle from qtd */
+		}
+		info1 |= maxp << 16;
+
+		info2 |= (FUSBH200_TUNE_MULT_TT << 30);
+
+		/* Some Freescale processors have an erratum in which the
+		 * port number in the queue head was 0..N-1 instead of 1..N.
+		 */
+		if (fusbh200_has_fsl_portno_bug(fusbh200))
+			info2 |= (urb->dev->ttport-1) << 23;
+		else
+			info2 |= urb->dev->ttport << 23;
+
+		/* set the address of the TT; for TDI's integrated
+		 * root hub tt, leave it zeroed.
+		 */
+		if (tt && tt->hub != fusbh200_to_hcd(fusbh200)->self.root_hub)
+			info2 |= tt->hub->devnum << 16;
+
+		/* NOTE:  if (PIPE_INTERRUPT) { scheduler sets c-mask } */
+
+		break;
+
+	case USB_SPEED_HIGH:		/* no TT involved */
+		info1 |= QH_HIGH_SPEED;
+		if (type == PIPE_CONTROL) {
+			info1 |= (FUSBH200_TUNE_RL_HS << 28);
+			info1 |= 64 << 16;	/* usb2 fixed maxpacket */
+			info1 |= QH_TOGGLE_CTL;	/* toggle from qtd */
+			info2 |= (FUSBH200_TUNE_MULT_HS << 30);
+		} else if (type == PIPE_BULK) {
+			info1 |= (FUSBH200_TUNE_RL_HS << 28);
+			/* The USB spec says that high speed bulk endpoints
+			 * always use 512 byte maxpacket.  But some device
+			 * vendors decided to ignore that, and MSFT is happy
+			 * to help them do so.  So now people expect to use
+			 * such nonconformant devices with Linux too; sigh.
+			 */
+			info1 |= max_packet(maxp) << 16;
+			info2 |= (FUSBH200_TUNE_MULT_HS << 30);
+		} else {		/* PIPE_INTERRUPT */
+			info1 |= max_packet (maxp) << 16;
+			info2 |= hb_mult (maxp) << 30;
+		}
+		break;
+	default:
+		fusbh200_dbg(fusbh200, "bogus dev %p speed %d\n", urb->dev,
+			urb->dev->speed);
+done:
+		qh_destroy(fusbh200, qh);
+		return NULL;
+	}
+
+	/* NOTE:  if (PIPE_INTERRUPT) { scheduler sets s-mask } */
+
+	/* init as live, toggle clear, advance to dummy */
+	qh->qh_state = QH_STATE_IDLE;
+	hw = qh->hw;
+	hw->hw_info1 = cpu_to_hc32(fusbh200, info1);
+	hw->hw_info2 = cpu_to_hc32(fusbh200, info2);
+	qh->is_out = !is_input;
+	usb_settoggle (urb->dev, usb_pipeendpoint (urb->pipe), !is_input, 1);
+	qh_refresh (fusbh200, qh);
+	return qh;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void enable_async(struct fusbh200_hcd *fusbh200)
+{
+	if (fusbh200->async_count++)
+		return;
+
+	/* Stop waiting to turn off the async schedule */
+	fusbh200->enabled_hrtimer_events &= ~BIT(FUSBH200_HRTIMER_DISABLE_ASYNC);
+
+	/* Don't start the schedule until ASS is 0 */
+	fusbh200_poll_ASS(fusbh200);
+	turn_on_io_watchdog(fusbh200);
+}
+
+static void disable_async(struct fusbh200_hcd *fusbh200)
+{
+	if (--fusbh200->async_count)
+		return;
+
+	/* The async schedule and async_unlink list are supposed to be empty */
+	WARN_ON(fusbh200->async->qh_next.qh || fusbh200->async_unlink);
+
+	/* Don't turn off the schedule until ASS is 1 */
+	fusbh200_poll_ASS(fusbh200);
+}
+
+/* move qh (and its qtds) onto async queue; maybe enable queue.  */
+
+static void qh_link_async (struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{
+	__hc32		dma = QH_NEXT(fusbh200, qh->qh_dma);
+	struct fusbh200_qh	*head;
+
+	/* Don't link a QH if there's a Clear-TT-Buffer pending */
+	if (unlikely(qh->clearing_tt))
+		return;
+
+	WARN_ON(qh->qh_state != QH_STATE_IDLE);
+
+	/* clear halt and/or toggle; and maybe recover from silicon quirk */
+	qh_refresh(fusbh200, qh);
+
+	/* splice right after start */
+	head = fusbh200->async;
+	qh->qh_next = head->qh_next;
+	qh->hw->hw_next = head->hw->hw_next;
+	wmb ();
+
+	head->qh_next.qh = qh;
+	head->hw->hw_next = dma;
+
+	qh->xacterrs = 0;
+	qh->qh_state = QH_STATE_LINKED;
+	/* qtd completions reported later by interrupt */
+
+	enable_async(fusbh200);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * For control/bulk/interrupt, return QH with these TDs appended.
+ * Allocates and initializes the QH if necessary.
+ * Returns null if it can't allocate a QH it needs to.
+ * If the QH has TDs (urbs) already, that's great.
+ */
+static struct fusbh200_qh *qh_append_tds (
+	struct fusbh200_hcd		*fusbh200,
+	struct urb		*urb,
+	struct list_head	*qtd_list,
+	int			epnum,
+	void			**ptr
+)
+{
+	struct fusbh200_qh		*qh = NULL;
+	__hc32			qh_addr_mask = cpu_to_hc32(fusbh200, 0x7f);
+
+	qh = (struct fusbh200_qh *) *ptr;
+	if (unlikely (qh == NULL)) {
+		/* can't sleep here, we have fusbh200->lock... */
+		qh = qh_make (fusbh200, urb, GFP_ATOMIC);
+		*ptr = qh;
+	}
+	if (likely (qh != NULL)) {
+		struct fusbh200_qtd	*qtd;
+
+		if (unlikely (list_empty (qtd_list)))
+			qtd = NULL;
+		else
+			qtd = list_entry (qtd_list->next, struct fusbh200_qtd,
+					qtd_list);
+
+		/* control qh may need patching ... */
+		if (unlikely (epnum == 0)) {
+
+                        /* usb_reset_device() briefly reverts to address 0 */
+                        if (usb_pipedevice (urb->pipe) == 0)
+				qh->hw->hw_info1 &= ~qh_addr_mask;
+		}
+
+		/* just one way to queue requests: swap with the dummy qtd.
+		 * only hc or qh_refresh() ever modify the overlay.
+		 */
+		if (likely (qtd != NULL)) {
+			struct fusbh200_qtd		*dummy;
+			dma_addr_t		dma;
+			__hc32			token;
+
+			/* to avoid racing the HC, use the dummy td instead of
+			 * the first td of our list (becomes new dummy).  both
+			 * tds stay deactivated until we're done, when the
+			 * HC is allowed to fetch the old dummy (4.10.2).
+			 */
+			token = qtd->hw_token;
+			qtd->hw_token = HALT_BIT(fusbh200);
+
+			dummy = qh->dummy;
+
+			dma = dummy->qtd_dma;
+			*dummy = *qtd;
+			dummy->qtd_dma = dma;
+
+			list_del (&qtd->qtd_list);
+			list_add (&dummy->qtd_list, qtd_list);
+			list_splice_tail(qtd_list, &qh->qtd_list);
+
+			fusbh200_qtd_init(fusbh200, qtd, qtd->qtd_dma);
+			qh->dummy = qtd;
+
+			/* hc must see the new dummy at list end */
+			dma = qtd->qtd_dma;
+			qtd = list_entry (qh->qtd_list.prev,
+					struct fusbh200_qtd, qtd_list);
+			qtd->hw_next = QTD_NEXT(fusbh200, dma);
+
+			/* let the hc process these next qtds */
+			wmb ();
+			dummy->hw_token = token;
+
+			urb->hcpriv = qh;
+		}
+	}
+	return qh;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int
+submit_async (
+	struct fusbh200_hcd		*fusbh200,
+	struct urb		*urb,
+	struct list_head	*qtd_list,
+	gfp_t			mem_flags
+) {
+	int			epnum;
+	unsigned long		flags;
+	struct fusbh200_qh		*qh = NULL;
+	int			rc;
+
+	epnum = urb->ep->desc.bEndpointAddress;
+
+#ifdef FUSBH200_URB_TRACE
+	{
+		struct fusbh200_qtd *qtd;
+		qtd = list_entry(qtd_list->next, struct fusbh200_qtd, qtd_list);
+		fusbh200_dbg(fusbh200,
+			 "%s %s urb %p ep%d%s len %d, qtd %p [qh %p]\n",
+			 __func__, urb->dev->devpath, urb,
+			 epnum & 0x0f, (epnum & USB_DIR_IN) ? "in" : "out",
+			 urb->transfer_buffer_length,
+			 qtd, urb->ep->hcpriv);
+	}
+#endif
+
+	spin_lock_irqsave (&fusbh200->lock, flags);
+	if (unlikely(!HCD_HW_ACCESSIBLE(fusbh200_to_hcd(fusbh200)))) {
+		rc = -ESHUTDOWN;
+		goto done;
+	}
+	rc = usb_hcd_link_urb_to_ep(fusbh200_to_hcd(fusbh200), urb);
+	if (unlikely(rc))
+		goto done;
+
+	qh = qh_append_tds(fusbh200, urb, qtd_list, epnum, &urb->ep->hcpriv);
+	if (unlikely(qh == NULL)) {
+		usb_hcd_unlink_urb_from_ep(fusbh200_to_hcd(fusbh200), urb);
+		rc = -ENOMEM;
+		goto done;
+	}
+
+	/* Control/bulk operations through TTs don't need scheduling,
+	 * the HC and TT handle it when the TT has a buffer ready.
+	 */
+	if (likely (qh->qh_state == QH_STATE_IDLE))
+		qh_link_async(fusbh200, qh);
+ done:
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+	if (unlikely (qh == NULL))
+		qtd_list_free (fusbh200, urb, qtd_list);
+	return rc;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void single_unlink_async(struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{
+	struct fusbh200_qh		*prev;
+
+	/* Add to the end of the list of QHs waiting for the next IAAD */
+	qh->qh_state = QH_STATE_UNLINK;
+	if (fusbh200->async_unlink)
+		fusbh200->async_unlink_last->unlink_next = qh;
+	else
+		fusbh200->async_unlink = qh;
+	fusbh200->async_unlink_last = qh;
+
+	/* Unlink it from the schedule */
+	prev = fusbh200->async;
+	while (prev->qh_next.qh != qh)
+		prev = prev->qh_next.qh;
+
+	prev->hw->hw_next = qh->hw->hw_next;
+	prev->qh_next = qh->qh_next;
+	if (fusbh200->qh_scan_next == qh)
+		fusbh200->qh_scan_next = qh->qh_next.qh;
+}
+
+static void start_iaa_cycle(struct fusbh200_hcd *fusbh200, bool nested)
+{
+	/*
+	 * Do nothing if an IAA cycle is already running or
+	 * if one will be started shortly.
+	 */
+	if (fusbh200->async_iaa || fusbh200->async_unlinking)
+		return;
+
+	/* Do all the waiting QHs at once */
+	fusbh200->async_iaa = fusbh200->async_unlink;
+	fusbh200->async_unlink = NULL;
+
+	/* If the controller isn't running, we don't have to wait for it */
+	if (unlikely(fusbh200->rh_state < FUSBH200_RH_RUNNING)) {
+		if (!nested)		/* Avoid recursion */
+			end_unlink_async(fusbh200);
+
+	/* Otherwise start a new IAA cycle */
+	} else if (likely(fusbh200->rh_state == FUSBH200_RH_RUNNING)) {
+		/* Make sure the unlinks are all visible to the hardware */
+		wmb();
+
+		fusbh200_writel(fusbh200, fusbh200->command | CMD_IAAD,
+				&fusbh200->regs->command);
+		fusbh200_readl(fusbh200, &fusbh200->regs->command);
+		fusbh200_enable_event(fusbh200, FUSBH200_HRTIMER_IAA_WATCHDOG, true);
+	}
+}
+
+/* the async qh for the qtds being unlinked are now gone from the HC */
+
+static void end_unlink_async(struct fusbh200_hcd *fusbh200)
+{
+	struct fusbh200_qh		*qh;
+
+	/* Process the idle QHs */
+ restart:
+	fusbh200->async_unlinking = true;
+	while (fusbh200->async_iaa) {
+		qh = fusbh200->async_iaa;
+		fusbh200->async_iaa = qh->unlink_next;
+		qh->unlink_next = NULL;
+
+		qh->qh_state = QH_STATE_IDLE;
+		qh->qh_next.qh = NULL;
+
+		qh_completions(fusbh200, qh);
+		if (!list_empty(&qh->qtd_list) &&
+				fusbh200->rh_state == FUSBH200_RH_RUNNING)
+			qh_link_async(fusbh200, qh);
+		disable_async(fusbh200);
+	}
+	fusbh200->async_unlinking = false;
+
+	/* Start a new IAA cycle if any QHs are waiting for it */
+	if (fusbh200->async_unlink) {
+		start_iaa_cycle(fusbh200, true);
+		if (unlikely(fusbh200->rh_state < FUSBH200_RH_RUNNING))
+			goto restart;
+	}
+}
+
+static void unlink_empty_async(struct fusbh200_hcd *fusbh200)
+{
+	struct fusbh200_qh		*qh, *next;
+	bool			stopped = (fusbh200->rh_state < FUSBH200_RH_RUNNING);
+	bool			check_unlinks_later = false;
+
+	/* Unlink all the async QHs that have been empty for a timer cycle */
+	next = fusbh200->async->qh_next.qh;
+	while (next) {
+		qh = next;
+		next = qh->qh_next.qh;
+
+		if (list_empty(&qh->qtd_list) &&
+				qh->qh_state == QH_STATE_LINKED) {
+			if (!stopped && qh->unlink_cycle ==
+					fusbh200->async_unlink_cycle)
+				check_unlinks_later = true;
+			else
+				single_unlink_async(fusbh200, qh);
+		}
+	}
+
+	/* Start a new IAA cycle if any QHs are waiting for it */
+	if (fusbh200->async_unlink)
+		start_iaa_cycle(fusbh200, false);
+
+	/* QHs that haven't been empty for long enough will be handled later */
+	if (check_unlinks_later) {
+		fusbh200_enable_event(fusbh200, FUSBH200_HRTIMER_ASYNC_UNLINKS, true);
+		++fusbh200->async_unlink_cycle;
+	}
+}
+
+/* makes sure the async qh will become idle */
+/* caller must own fusbh200->lock */
+
+static void start_unlink_async(struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{
+	/*
+	 * If the QH isn't linked then there's nothing we can do
+	 * unless we were called during a giveback, in which case
+	 * qh_completions() has to deal with it.
+	 */
+	if (qh->qh_state != QH_STATE_LINKED) {
+		if (qh->qh_state == QH_STATE_COMPLETING)
+			qh->needs_rescan = 1;
+		return;
+	}
+
+	single_unlink_async(fusbh200, qh);
+	start_iaa_cycle(fusbh200, false);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void scan_async (struct fusbh200_hcd *fusbh200)
+{
+	struct fusbh200_qh		*qh;
+	bool			check_unlinks_later = false;
+
+	fusbh200->qh_scan_next = fusbh200->async->qh_next.qh;
+	while (fusbh200->qh_scan_next) {
+		qh = fusbh200->qh_scan_next;
+		fusbh200->qh_scan_next = qh->qh_next.qh;
+ rescan:
+		/* clean any finished work for this qh */
+		if (!list_empty(&qh->qtd_list)) {
+			int temp;
+
+			/*
+			 * Unlinks could happen here; completion reporting
+			 * drops the lock.  That's why fusbh200->qh_scan_next
+			 * always holds the next qh to scan; if the next qh
+			 * gets unlinked then fusbh200->qh_scan_next is adjusted
+			 * in single_unlink_async().
+			 */
+			temp = qh_completions(fusbh200, qh);
+			if (qh->needs_rescan) {
+				start_unlink_async(fusbh200, qh);
+			} else if (list_empty(&qh->qtd_list)
+					&& qh->qh_state == QH_STATE_LINKED) {
+				qh->unlink_cycle = fusbh200->async_unlink_cycle;
+				check_unlinks_later = true;
+			} else if (temp != 0)
+				goto rescan;
+		}
+	}
+
+	/*
+	 * Unlink empty entries, reducing DMA usage as well
+	 * as HCD schedule-scanning costs.  Delay for any qh
+	 * we just scanned, there's a not-unusual case that it
+	 * doesn't stay idle for long.
+	 */
+	if (check_unlinks_later && fusbh200->rh_state == FUSBH200_RH_RUNNING &&
+			!(fusbh200->enabled_hrtimer_events &
+				BIT(FUSBH200_HRTIMER_ASYNC_UNLINKS))) {
+		fusbh200_enable_event(fusbh200, FUSBH200_HRTIMER_ASYNC_UNLINKS, true);
+		++fusbh200->async_unlink_cycle;
+	}
+}
+/*-------------------------------------------------------------------------*/
+/*
+ * EHCI scheduled transaction support:  interrupt, iso, split iso
+ * These are called "periodic" transactions in the EHCI spec.
+ *
+ * Note that for interrupt transfers, the QH/QTD manipulation is shared
+ * with the "asynchronous" transaction support (control/bulk transfers).
+ * The only real difference is in how interrupt transfers are scheduled.
+ *
+ * For ISO, we make an "iso_stream" head to serve the same role as a QH.
+ * It keeps track of every ITD (or SITD) that's linked, and holds enough
+ * pre-calculated schedule data to make appending to the queue be quick.
+ */
+
+static int fusbh200_get_frame (struct usb_hcd *hcd);
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * periodic_next_shadow - return "next" pointer on shadow list
+ * @periodic: host pointer to qh/itd
+ * @tag: hardware tag for type of this record
+ */
+static union fusbh200_shadow *
+periodic_next_shadow(struct fusbh200_hcd *fusbh200, union fusbh200_shadow *periodic,
+		__hc32 tag)
+{
+	switch (hc32_to_cpu(fusbh200, tag)) {
+	case Q_TYPE_QH:
+		return &periodic->qh->qh_next;
+	case Q_TYPE_FSTN:
+		return &periodic->fstn->fstn_next;
+	default:
+		return &periodic->itd->itd_next;
+	}
+}
+
+static __hc32 *
+shadow_next_periodic(struct fusbh200_hcd *fusbh200, union fusbh200_shadow *periodic,
+		__hc32 tag)
+{
+	switch (hc32_to_cpu(fusbh200, tag)) {
+	/* our fusbh200_shadow.qh is actually software part */
+	case Q_TYPE_QH:
+		return &periodic->qh->hw->hw_next;
+	/* others are hw parts */
+	default:
+		return periodic->hw_next;
+	}
+}
+
+/* caller must hold fusbh200->lock */
+static void periodic_unlink (struct fusbh200_hcd *fusbh200, unsigned frame, void *ptr)
+{
+	union fusbh200_shadow	*prev_p = &fusbh200->pshadow[frame];
+	__hc32			*hw_p = &fusbh200->periodic[frame];
+	union fusbh200_shadow	here = *prev_p;
+
+	/* find predecessor of "ptr"; hw and shadow lists are in sync */
+	while (here.ptr && here.ptr != ptr) {
+		prev_p = periodic_next_shadow(fusbh200, prev_p,
+				Q_NEXT_TYPE(fusbh200, *hw_p));
+		hw_p = shadow_next_periodic(fusbh200, &here,
+				Q_NEXT_TYPE(fusbh200, *hw_p));
+		here = *prev_p;
+	}
+	/* an interrupt entry (at list end) could have been shared */
+	if (!here.ptr)
+		return;
+
+	/* update shadow and hardware lists ... the old "next" pointers
+	 * from ptr may still be in use, the caller updates them.
+	 */
+	*prev_p = *periodic_next_shadow(fusbh200, &here,
+			Q_NEXT_TYPE(fusbh200, *hw_p));
+
+	*hw_p = *shadow_next_periodic(fusbh200, &here,
+				Q_NEXT_TYPE(fusbh200, *hw_p));
+}
+
+/* how many of the uframe's 125 usecs are allocated? */
+static unsigned short
+periodic_usecs (struct fusbh200_hcd *fusbh200, unsigned frame, unsigned uframe)
+{
+	__hc32			*hw_p = &fusbh200->periodic [frame];
+	union fusbh200_shadow	*q = &fusbh200->pshadow [frame];
+	unsigned		usecs = 0;
+	struct fusbh200_qh_hw	*hw;
+
+	while (q->ptr) {
+		switch (hc32_to_cpu(fusbh200, Q_NEXT_TYPE(fusbh200, *hw_p))) {
+		case Q_TYPE_QH:
+			hw = q->qh->hw;
+			/* is it in the S-mask? */
+			if (hw->hw_info2 & cpu_to_hc32(fusbh200, 1 << uframe))
+				usecs += q->qh->usecs;
+			/* ... or C-mask? */
+			if (hw->hw_info2 & cpu_to_hc32(fusbh200,
+					1 << (8 + uframe)))
+				usecs += q->qh->c_usecs;
+			hw_p = &hw->hw_next;
+			q = &q->qh->qh_next;
+			break;
+		// case Q_TYPE_FSTN:
+		default:
+			/* for "save place" FSTNs, count the relevant INTR
+			 * bandwidth from the previous frame
+			 */
+			if (q->fstn->hw_prev != FUSBH200_LIST_END(fusbh200)) {
+				fusbh200_dbg (fusbh200, "ignoring FSTN cost ...\n");
+			}
+			hw_p = &q->fstn->hw_next;
+			q = &q->fstn->fstn_next;
+			break;
+		case Q_TYPE_ITD:
+			if (q->itd->hw_transaction[uframe])
+				usecs += q->itd->stream->usecs;
+			hw_p = &q->itd->hw_next;
+			q = &q->itd->itd_next;
+			break;
+		}
+	}
+#ifdef	DEBUG
+	if (usecs > fusbh200->uframe_periodic_max)
+		fusbh200_err (fusbh200, "uframe %d sched overrun: %d usecs\n",
+			frame * 8 + uframe, usecs);
+#endif
+	return usecs;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int same_tt (struct usb_device *dev1, struct usb_device *dev2)
+{
+	if (!dev1->tt || !dev2->tt)
+		return 0;
+	if (dev1->tt != dev2->tt)
+		return 0;
+	if (dev1->tt->multi)
+		return dev1->ttport == dev2->ttport;
+	else
+		return 1;
+}
+
+/* return true iff the device's transaction translator is available
+ * for a periodic transfer starting at the specified frame, using
+ * all the uframes in the mask.
+ */
+static int tt_no_collision (
+	struct fusbh200_hcd		*fusbh200,
+	unsigned		period,
+	struct usb_device	*dev,
+	unsigned		frame,
+	u32			uf_mask
+)
+{
+	if (period == 0)	/* error */
+		return 0;
+
+	/* note bandwidth wastage:  split never follows csplit
+	 * (different dev or endpoint) until the next uframe.
+	 * calling convention doesn't make that distinction.
+	 */
+	for (; frame < fusbh200->periodic_size; frame += period) {
+		union fusbh200_shadow	here;
+		__hc32			type;
+		struct fusbh200_qh_hw	*hw;
+
+		here = fusbh200->pshadow [frame];
+		type = Q_NEXT_TYPE(fusbh200, fusbh200->periodic [frame]);
+		while (here.ptr) {
+			switch (hc32_to_cpu(fusbh200, type)) {
+			case Q_TYPE_ITD:
+				type = Q_NEXT_TYPE(fusbh200, here.itd->hw_next);
+				here = here.itd->itd_next;
+				continue;
+			case Q_TYPE_QH:
+				hw = here.qh->hw;
+				if (same_tt (dev, here.qh->dev)) {
+					u32		mask;
+
+					mask = hc32_to_cpu(fusbh200,
+							hw->hw_info2);
+					/* "knows" no gap is needed */
+					mask |= mask >> 8;
+					if (mask & uf_mask)
+						break;
+				}
+				type = Q_NEXT_TYPE(fusbh200, hw->hw_next);
+				here = here.qh->qh_next;
+				continue;
+			// case Q_TYPE_FSTN:
+			default:
+				fusbh200_dbg (fusbh200,
+					"periodic frame %d bogus type %d\n",
+					frame, type);
+			}
+
+			/* collision or error */
+			return 0;
+		}
+	}
+
+	/* no collision */
+	return 1;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void enable_periodic(struct fusbh200_hcd *fusbh200)
+{
+	if (fusbh200->periodic_count++)
+		return;
+
+	/* Stop waiting to turn off the periodic schedule */
+	fusbh200->enabled_hrtimer_events &= ~BIT(FUSBH200_HRTIMER_DISABLE_PERIODIC);
+
+	/* Don't start the schedule until PSS is 0 */
+	fusbh200_poll_PSS(fusbh200);
+	turn_on_io_watchdog(fusbh200);
+}
+
+static void disable_periodic(struct fusbh200_hcd *fusbh200)
+{
+	if (--fusbh200->periodic_count)
+		return;
+
+	/* Don't turn off the schedule until PSS is 1 */
+	fusbh200_poll_PSS(fusbh200);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* periodic schedule slots have iso tds (normal or split) first, then a
+ * sparse tree for active interrupt transfers.
+ *
+ * this just links in a qh; caller guarantees uframe masks are set right.
+ * no FSTN support (yet; fusbh200 0.96+)
+ */
+static void qh_link_periodic(struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{
+	unsigned	i;
+	unsigned	period = qh->period;
+
+	dev_dbg (&qh->dev->dev,
+		"link qh%d-%04x/%p start %d [%d/%d us]\n",
+		period, hc32_to_cpup(fusbh200, &qh->hw->hw_info2)
+			& (QH_CMASK | QH_SMASK),
+		qh, qh->start, qh->usecs, qh->c_usecs);
+
+	/* high bandwidth, or otherwise every microframe */
+	if (period == 0)
+		period = 1;
+
+	for (i = qh->start; i < fusbh200->periodic_size; i += period) {
+		union fusbh200_shadow	*prev = &fusbh200->pshadow[i];
+		__hc32			*hw_p = &fusbh200->periodic[i];
+		union fusbh200_shadow	here = *prev;
+		__hc32			type = 0;
+
+		/* skip the iso nodes at list head */
+		while (here.ptr) {
+			type = Q_NEXT_TYPE(fusbh200, *hw_p);
+			if (type == cpu_to_hc32(fusbh200, Q_TYPE_QH))
+				break;
+			prev = periodic_next_shadow(fusbh200, prev, type);
+			hw_p = shadow_next_periodic(fusbh200, &here, type);
+			here = *prev;
+		}
+
+		/* sorting each branch by period (slow-->fast)
+		 * enables sharing interior tree nodes
+		 */
+		while (here.ptr && qh != here.qh) {
+			if (qh->period > here.qh->period)
+				break;
+			prev = &here.qh->qh_next;
+			hw_p = &here.qh->hw->hw_next;
+			here = *prev;
+		}
+		/* link in this qh, unless some earlier pass did that */
+		if (qh != here.qh) {
+			qh->qh_next = here;
+			if (here.qh)
+				qh->hw->hw_next = *hw_p;
+			wmb ();
+			prev->qh = qh;
+			*hw_p = QH_NEXT (fusbh200, qh->qh_dma);
+		}
+	}
+	qh->qh_state = QH_STATE_LINKED;
+	qh->xacterrs = 0;
+
+	/* update per-qh bandwidth for usbfs */
+	fusbh200_to_hcd(fusbh200)->self.bandwidth_allocated += qh->period
+		? ((qh->usecs + qh->c_usecs) / qh->period)
+		: (qh->usecs * 8);
+
+	list_add(&qh->intr_node, &fusbh200->intr_qh_list);
+
+	/* maybe enable periodic schedule processing */
+	++fusbh200->intr_count;
+	enable_periodic(fusbh200);
+}
+
+static void qh_unlink_periodic(struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{
+	unsigned	i;
+	unsigned	period;
+
+	/*
+	 * If qh is for a low/full-speed device, simply unlinking it
+	 * could interfere with an ongoing split transaction.  To unlink
+	 * it safely would require setting the QH_INACTIVATE bit and
+	 * waiting at least one frame, as described in EHCI 4.12.2.5.
+	 *
+	 * We won't bother with any of this.  Instead, we assume that the
+	 * only reason for unlinking an interrupt QH while the current URB
+	 * is still active is to dequeue all the URBs (flush the whole
+	 * endpoint queue).
+	 *
+	 * If rebalancing the periodic schedule is ever implemented, this
+	 * approach will no longer be valid.
+	 */
+
+	/* high bandwidth, or otherwise part of every microframe */
+	if ((period = qh->period) == 0)
+		period = 1;
+
+	for (i = qh->start; i < fusbh200->periodic_size; i += period)
+		periodic_unlink (fusbh200, i, qh);
+
+	/* update per-qh bandwidth for usbfs */
+	fusbh200_to_hcd(fusbh200)->self.bandwidth_allocated -= qh->period
+		? ((qh->usecs + qh->c_usecs) / qh->period)
+		: (qh->usecs * 8);
+
+	dev_dbg (&qh->dev->dev,
+		"unlink qh%d-%04x/%p start %d [%d/%d us]\n",
+		qh->period,
+		hc32_to_cpup(fusbh200, &qh->hw->hw_info2) & (QH_CMASK | QH_SMASK),
+		qh, qh->start, qh->usecs, qh->c_usecs);
+
+	/* qh->qh_next still "live" to HC */
+	qh->qh_state = QH_STATE_UNLINK;
+	qh->qh_next.ptr = NULL;
+
+	if (fusbh200->qh_scan_next == qh)
+		fusbh200->qh_scan_next = list_entry(qh->intr_node.next,
+				struct fusbh200_qh, intr_node);
+	list_del(&qh->intr_node);
+}
+
+static void start_unlink_intr(struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{
+	/* If the QH isn't linked then there's nothing we can do
+	 * unless we were called during a giveback, in which case
+	 * qh_completions() has to deal with it.
+	 */
+	if (qh->qh_state != QH_STATE_LINKED) {
+		if (qh->qh_state == QH_STATE_COMPLETING)
+			qh->needs_rescan = 1;
+		return;
+	}
+
+	qh_unlink_periodic (fusbh200, qh);
+
+	/* Make sure the unlinks are visible before starting the timer */
+	wmb();
+
+	/*
+	 * The EHCI spec doesn't say how long it takes the controller to
+	 * stop accessing an unlinked interrupt QH.  The timer delay is
+	 * 9 uframes; presumably that will be long enough.
+	 */
+	qh->unlink_cycle = fusbh200->intr_unlink_cycle;
+
+	/* New entries go at the end of the intr_unlink list */
+	if (fusbh200->intr_unlink)
+		fusbh200->intr_unlink_last->unlink_next = qh;
+	else
+		fusbh200->intr_unlink = qh;
+	fusbh200->intr_unlink_last = qh;
+
+	if (fusbh200->intr_unlinking)
+		;	/* Avoid recursive calls */
+	else if (fusbh200->rh_state < FUSBH200_RH_RUNNING)
+		fusbh200_handle_intr_unlinks(fusbh200);
+	else if (fusbh200->intr_unlink == qh) {
+		fusbh200_enable_event(fusbh200, FUSBH200_HRTIMER_UNLINK_INTR, true);
+		++fusbh200->intr_unlink_cycle;
+	}
+}
+
+static void end_unlink_intr(struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{
+	struct fusbh200_qh_hw	*hw = qh->hw;
+	int			rc;
+
+	qh->qh_state = QH_STATE_IDLE;
+	hw->hw_next = FUSBH200_LIST_END(fusbh200);
+
+	qh_completions(fusbh200, qh);
+
+	/* reschedule QH iff another request is queued */
+	if (!list_empty(&qh->qtd_list) && fusbh200->rh_state == FUSBH200_RH_RUNNING) {
+		rc = qh_schedule(fusbh200, qh);
+
+		/* An error here likely indicates handshake failure
+		 * or no space left in the schedule.  Neither fault
+		 * should happen often ...
+		 *
+		 * FIXME kill the now-dysfunctional queued urbs
+		 */
+		if (rc != 0)
+			fusbh200_err(fusbh200, "can't reschedule qh %p, err %d\n",
+					qh, rc);
+	}
+
+	/* maybe turn off periodic schedule */
+	--fusbh200->intr_count;
+	disable_periodic(fusbh200);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int check_period (
+	struct fusbh200_hcd *fusbh200,
+	unsigned	frame,
+	unsigned	uframe,
+	unsigned	period,
+	unsigned	usecs
+) {
+	int		claimed;
+
+	/* complete split running into next frame?
+	 * given FSTN support, we could sometimes check...
+	 */
+	if (uframe >= 8)
+		return 0;
+
+	/* convert "usecs we need" to "max already claimed" */
+	usecs = fusbh200->uframe_periodic_max - usecs;
+
+	/* we "know" 2 and 4 uframe intervals were rejected; so
+	 * for period 0, check _every_ microframe in the schedule.
+	 */
+	if (unlikely (period == 0)) {
+		do {
+			for (uframe = 0; uframe < 7; uframe++) {
+				claimed = periodic_usecs (fusbh200, frame, uframe);
+				if (claimed > usecs)
+					return 0;
+			}
+		} while ((frame += 1) < fusbh200->periodic_size);
+
+	/* just check the specified uframe, at that period */
+	} else {
+		do {
+			claimed = periodic_usecs (fusbh200, frame, uframe);
+			if (claimed > usecs)
+				return 0;
+		} while ((frame += period) < fusbh200->periodic_size);
+	}
+
+	// success!
+	return 1;
+}
+
+static int check_intr_schedule (
+	struct fusbh200_hcd		*fusbh200,
+	unsigned		frame,
+	unsigned		uframe,
+	const struct fusbh200_qh	*qh,
+	__hc32			*c_maskp
+)
+{
+	int		retval = -ENOSPC;
+	u8		mask = 0;
+
+	if (qh->c_usecs && uframe >= 6)		/* FSTN territory? */
+		goto done;
+
+	if (!check_period (fusbh200, frame, uframe, qh->period, qh->usecs))
+		goto done;
+	if (!qh->c_usecs) {
+		retval = 0;
+		*c_maskp = 0;
+		goto done;
+	}
+
+	/* Make sure this tt's buffer is also available for CSPLITs.
+	 * We pessimize a bit; probably the typical full speed case
+	 * doesn't need the second CSPLIT.
+	 *
+	 * NOTE:  both SPLIT and CSPLIT could be checked in just
+	 * one smart pass...
+	 */
+	mask = 0x03 << (uframe + qh->gap_uf);
+	*c_maskp = cpu_to_hc32(fusbh200, mask << 8);
+
+	mask |= 1 << uframe;
+	if (tt_no_collision (fusbh200, qh->period, qh->dev, frame, mask)) {
+		if (!check_period (fusbh200, frame, uframe + qh->gap_uf + 1,
+					qh->period, qh->c_usecs))
+			goto done;
+		if (!check_period (fusbh200, frame, uframe + qh->gap_uf,
+					qh->period, qh->c_usecs))
+			goto done;
+		retval = 0;
+	}
+done:
+	return retval;
+}
+
+/* "first fit" scheduling policy used the first time through,
+ * or when the previous schedule slot can't be re-used.
+ */
+static int qh_schedule(struct fusbh200_hcd *fusbh200, struct fusbh200_qh *qh)
+{
+	int		status;
+	unsigned	uframe;
+	__hc32		c_mask;
+	unsigned	frame;		/* 0..(qh->period - 1), or NO_FRAME */
+	struct fusbh200_qh_hw	*hw = qh->hw;
+
+	qh_refresh(fusbh200, qh);
+	hw->hw_next = FUSBH200_LIST_END(fusbh200);
+	frame = qh->start;
+
+	/* reuse the previous schedule slots, if we can */
+	if (frame < qh->period) {
+		uframe = ffs(hc32_to_cpup(fusbh200, &hw->hw_info2) & QH_SMASK);
+		status = check_intr_schedule (fusbh200, frame, --uframe,
+				qh, &c_mask);
+	} else {
+		uframe = 0;
+		c_mask = 0;
+		status = -ENOSPC;
+	}
+
+	/* else scan the schedule to find a group of slots such that all
+	 * uframes have enough periodic bandwidth available.
+	 */
+	if (status) {
+		/* "normal" case, uframing flexible except with splits */
+		if (qh->period) {
+			int		i;
+
+			for (i = qh->period; status && i > 0; --i) {
+				frame = ++fusbh200->random_frame % qh->period;
+				for (uframe = 0; uframe < 8; uframe++) {
+					status = check_intr_schedule (fusbh200,
+							frame, uframe, qh,
+							&c_mask);
+					if (status == 0)
+						break;
+				}
+			}
+
+		/* qh->period == 0 means every uframe */
+		} else {
+			frame = 0;
+			status = check_intr_schedule (fusbh200, 0, 0, qh, &c_mask);
+		}
+		if (status)
+			goto done;
+		qh->start = frame;
+
+		/* reset S-frame and (maybe) C-frame masks */
+		hw->hw_info2 &= cpu_to_hc32(fusbh200, ~(QH_CMASK | QH_SMASK));
+		hw->hw_info2 |= qh->period
+			? cpu_to_hc32(fusbh200, 1 << uframe)
+			: cpu_to_hc32(fusbh200, QH_SMASK);
+		hw->hw_info2 |= c_mask;
+	} else
+		fusbh200_dbg (fusbh200, "reused qh %p schedule\n", qh);
+
+	/* stuff into the periodic schedule */
+	qh_link_periodic(fusbh200, qh);
+done:
+	return status;
+}
+
+static int intr_submit (
+	struct fusbh200_hcd		*fusbh200,
+	struct urb		*urb,
+	struct list_head	*qtd_list,
+	gfp_t			mem_flags
+) {
+	unsigned		epnum;
+	unsigned long		flags;
+	struct fusbh200_qh		*qh;
+	int			status;
+	struct list_head	empty;
+
+	/* get endpoint and transfer/schedule data */
+	epnum = urb->ep->desc.bEndpointAddress;
+
+	spin_lock_irqsave (&fusbh200->lock, flags);
+
+	if (unlikely(!HCD_HW_ACCESSIBLE(fusbh200_to_hcd(fusbh200)))) {
+		status = -ESHUTDOWN;
+		goto done_not_linked;
+	}
+	status = usb_hcd_link_urb_to_ep(fusbh200_to_hcd(fusbh200), urb);
+	if (unlikely(status))
+		goto done_not_linked;
+
+	/* get qh and force any scheduling errors */
+	INIT_LIST_HEAD (&empty);
+	qh = qh_append_tds(fusbh200, urb, &empty, epnum, &urb->ep->hcpriv);
+	if (qh == NULL) {
+		status = -ENOMEM;
+		goto done;
+	}
+	if (qh->qh_state == QH_STATE_IDLE) {
+		if ((status = qh_schedule (fusbh200, qh)) != 0)
+			goto done;
+	}
+
+	/* then queue the urb's tds to the qh */
+	qh = qh_append_tds(fusbh200, urb, qtd_list, epnum, &urb->ep->hcpriv);
+	BUG_ON (qh == NULL);
+
+	/* ... update usbfs periodic stats */
+	fusbh200_to_hcd(fusbh200)->self.bandwidth_int_reqs++;
+
+done:
+	if (unlikely(status))
+		usb_hcd_unlink_urb_from_ep(fusbh200_to_hcd(fusbh200), urb);
+done_not_linked:
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+	if (status)
+		qtd_list_free (fusbh200, urb, qtd_list);
+
+	return status;
+}
+
+static void scan_intr(struct fusbh200_hcd *fusbh200)
+{
+	struct fusbh200_qh		*qh;
+
+	list_for_each_entry_safe(qh, fusbh200->qh_scan_next, &fusbh200->intr_qh_list,
+			intr_node) {
+ rescan:
+		/* clean any finished work for this qh */
+		if (!list_empty(&qh->qtd_list)) {
+			int temp;
+
+			/*
+			 * Unlinks could happen here; completion reporting
+			 * drops the lock.  That's why fusbh200->qh_scan_next
+			 * always holds the next qh to scan; if the next qh
+			 * gets unlinked then fusbh200->qh_scan_next is adjusted
+			 * in qh_unlink_periodic().
+			 */
+			temp = qh_completions(fusbh200, qh);
+			if (unlikely(qh->needs_rescan ||
+					(list_empty(&qh->qtd_list) &&
+						qh->qh_state == QH_STATE_LINKED)))
+				start_unlink_intr(fusbh200, qh);
+			else if (temp != 0)
+				goto rescan;
+		}
+	}
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* fusbh200_iso_stream ops work with both ITD and SITD */
+
+static struct fusbh200_iso_stream *
+iso_stream_alloc (gfp_t mem_flags)
+{
+	struct fusbh200_iso_stream *stream;
+
+	stream = kzalloc(sizeof *stream, mem_flags);
+	if (likely (stream != NULL)) {
+		INIT_LIST_HEAD(&stream->td_list);
+		INIT_LIST_HEAD(&stream->free_list);
+		stream->next_uframe = -1;
+	}
+	return stream;
+}
+
+static void
+iso_stream_init (
+	struct fusbh200_hcd		*fusbh200,
+	struct fusbh200_iso_stream	*stream,
+	struct usb_device	*dev,
+	int			pipe,
+	unsigned		interval
+)
+{
+	u32			buf1;
+	unsigned		epnum, maxp;
+	int			is_input;
+	long			bandwidth;
+	unsigned 		multi;
+
+	/*
+	 * this might be a "high bandwidth" highspeed endpoint,
+	 * as encoded in the ep descriptor's wMaxPacket field
+	 */
+	epnum = usb_pipeendpoint (pipe);
+	is_input = usb_pipein (pipe) ? USB_DIR_IN : 0;
+	maxp = usb_maxpacket(dev, pipe, !is_input);
+	if (is_input) {
+		buf1 = (1 << 11);
+	} else {
+		buf1 = 0;
+	}
+
+	maxp = max_packet(maxp);
+	multi = hb_mult(maxp);
+	buf1 |= maxp;
+	maxp *= multi;
+
+	stream->buf0 = cpu_to_hc32(fusbh200, (epnum << 8) | dev->devnum);
+	stream->buf1 = cpu_to_hc32(fusbh200, buf1);
+	stream->buf2 = cpu_to_hc32(fusbh200, multi);
+
+	/* usbfs wants to report the average usecs per frame tied up
+	 * when transfers on this endpoint are scheduled ...
+	 */
+	if (dev->speed == USB_SPEED_FULL) {
+		interval <<= 3;
+		stream->usecs = NS_TO_US(usb_calc_bus_time(dev->speed,
+				is_input, 1, maxp));
+		stream->usecs /= 8;
+	} else {
+		stream->highspeed = 1;
+		stream->usecs = HS_USECS_ISO (maxp);
+	}
+	bandwidth = stream->usecs * 8;
+	bandwidth /= interval;
+
+	stream->bandwidth = bandwidth;
+	stream->udev = dev;
+	stream->bEndpointAddress = is_input | epnum;
+	stream->interval = interval;
+	stream->maxp = maxp;
+}
+
+static struct fusbh200_iso_stream *
+iso_stream_find (struct fusbh200_hcd *fusbh200, struct urb *urb)
+{
+	unsigned		epnum;
+	struct fusbh200_iso_stream	*stream;
+	struct usb_host_endpoint *ep;
+	unsigned long		flags;
+
+	epnum = usb_pipeendpoint (urb->pipe);
+	if (usb_pipein(urb->pipe))
+		ep = urb->dev->ep_in[epnum];
+	else
+		ep = urb->dev->ep_out[epnum];
+
+	spin_lock_irqsave (&fusbh200->lock, flags);
+	stream = ep->hcpriv;
+
+	if (unlikely (stream == NULL)) {
+		stream = iso_stream_alloc(GFP_ATOMIC);
+		if (likely (stream != NULL)) {
+			ep->hcpriv = stream;
+			stream->ep = ep;
+			iso_stream_init(fusbh200, stream, urb->dev, urb->pipe,
+					urb->interval);
+		}
+
+	/* if dev->ep [epnum] is a QH, hw is set */
+	} else if (unlikely (stream->hw != NULL)) {
+		fusbh200_dbg (fusbh200, "dev %s ep%d%s, not iso??\n",
+			urb->dev->devpath, epnum,
+			usb_pipein(urb->pipe) ? "in" : "out");
+		stream = NULL;
+	}
+
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+	return stream;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* fusbh200_iso_sched ops can be ITD-only or SITD-only */
+
+static struct fusbh200_iso_sched *
+iso_sched_alloc (unsigned packets, gfp_t mem_flags)
+{
+	struct fusbh200_iso_sched	*iso_sched;
+	int			size = sizeof *iso_sched;
+
+	size += packets * sizeof (struct fusbh200_iso_packet);
+	iso_sched = kzalloc(size, mem_flags);
+	if (likely (iso_sched != NULL)) {
+		INIT_LIST_HEAD (&iso_sched->td_list);
+	}
+	return iso_sched;
+}
+
+static inline void
+itd_sched_init(
+	struct fusbh200_hcd		*fusbh200,
+	struct fusbh200_iso_sched	*iso_sched,
+	struct fusbh200_iso_stream	*stream,
+	struct urb		*urb
+)
+{
+	unsigned	i;
+	dma_addr_t	dma = urb->transfer_dma;
+
+	/* how many uframes are needed for these transfers */
+	iso_sched->span = urb->number_of_packets * stream->interval;
+
+	/* figure out per-uframe itd fields that we'll need later
+	 * when we fit new itds into the schedule.
+	 */
+	for (i = 0; i < urb->number_of_packets; i++) {
+		struct fusbh200_iso_packet	*uframe = &iso_sched->packet [i];
+		unsigned		length;
+		dma_addr_t		buf;
+		u32			trans;
+
+		length = urb->iso_frame_desc [i].length;
+		buf = dma + urb->iso_frame_desc [i].offset;
+
+		trans = FUSBH200_ISOC_ACTIVE;
+		trans |= buf & 0x0fff;
+		if (unlikely (((i + 1) == urb->number_of_packets))
+				&& !(urb->transfer_flags & URB_NO_INTERRUPT))
+			trans |= FUSBH200_ITD_IOC;
+		trans |= length << 16;
+		uframe->transaction = cpu_to_hc32(fusbh200, trans);
+
+		/* might need to cross a buffer page within a uframe */
+		uframe->bufp = (buf & ~(u64)0x0fff);
+		buf += length;
+		if (unlikely ((uframe->bufp != (buf & ~(u64)0x0fff))))
+			uframe->cross = 1;
+	}
+}
+
+static void
+iso_sched_free (
+	struct fusbh200_iso_stream	*stream,
+	struct fusbh200_iso_sched	*iso_sched
+)
+{
+	if (!iso_sched)
+		return;
+	// caller must hold fusbh200->lock!
+	list_splice (&iso_sched->td_list, &stream->free_list);
+	kfree (iso_sched);
+}
+
+static int
+itd_urb_transaction (
+	struct fusbh200_iso_stream	*stream,
+	struct fusbh200_hcd		*fusbh200,
+	struct urb		*urb,
+	gfp_t			mem_flags
+)
+{
+	struct fusbh200_itd		*itd;
+	dma_addr_t		itd_dma;
+	int			i;
+	unsigned		num_itds;
+	struct fusbh200_iso_sched	*sched;
+	unsigned long		flags;
+
+	sched = iso_sched_alloc (urb->number_of_packets, mem_flags);
+	if (unlikely (sched == NULL))
+		return -ENOMEM;
+
+	itd_sched_init(fusbh200, sched, stream, urb);
+
+	if (urb->interval < 8)
+		num_itds = 1 + (sched->span + 7) / 8;
+	else
+		num_itds = urb->number_of_packets;
+
+	/* allocate/init ITDs */
+	spin_lock_irqsave (&fusbh200->lock, flags);
+	for (i = 0; i < num_itds; i++) {
+
+		/*
+		 * Use iTDs from the free list, but not iTDs that may
+		 * still be in use by the hardware.
+		 */
+		if (likely(!list_empty(&stream->free_list))) {
+			itd = list_first_entry(&stream->free_list,
+					struct fusbh200_itd, itd_list);
+			if (itd->frame == fusbh200->now_frame)
+				goto alloc_itd;
+			list_del (&itd->itd_list);
+			itd_dma = itd->itd_dma;
+		} else {
+ alloc_itd:
+			spin_unlock_irqrestore (&fusbh200->lock, flags);
+			itd = dma_pool_alloc (fusbh200->itd_pool, mem_flags,
+					&itd_dma);
+			spin_lock_irqsave (&fusbh200->lock, flags);
+			if (!itd) {
+				iso_sched_free(stream, sched);
+				spin_unlock_irqrestore(&fusbh200->lock, flags);
+				return -ENOMEM;
+			}
+		}
+
+		memset (itd, 0, sizeof *itd);
+		itd->itd_dma = itd_dma;
+		list_add (&itd->itd_list, &sched->td_list);
+	}
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+
+	/* temporarily store schedule info in hcpriv */
+	urb->hcpriv = sched;
+	urb->error_count = 0;
+	return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static inline int
+itd_slot_ok (
+	struct fusbh200_hcd		*fusbh200,
+	u32			mod,
+	u32			uframe,
+	u8			usecs,
+	u32			period
+)
+{
+	uframe %= period;
+	do {
+		/* can't commit more than uframe_periodic_max usec */
+		if (periodic_usecs (fusbh200, uframe >> 3, uframe & 0x7)
+				> (fusbh200->uframe_periodic_max - usecs))
+			return 0;
+
+		/* we know urb->interval is 2^N uframes */
+		uframe += period;
+	} while (uframe < mod);
+	return 1;
+}
+
+/*
+ * This scheduler plans almost as far into the future as it has actual
+ * periodic schedule slots.  (Affected by TUNE_FLS, which defaults to
+ * "as small as possible" to be cache-friendlier.)  That limits the size
+ * transfers you can stream reliably; avoid more than 64 msec per urb.
+ * Also avoid queue depths of less than fusbh200's worst irq latency (affected
+ * by the per-urb URB_NO_INTERRUPT hint, the log2_irq_thresh module parameter,
+ * and other factors); or more than about 230 msec total (for portability,
+ * given FUSBH200_TUNE_FLS and the slop).  Or, write a smarter scheduler!
+ */
+
+#define SCHEDULE_SLOP	80	/* microframes */
+
+static int
+iso_stream_schedule (
+	struct fusbh200_hcd		*fusbh200,
+	struct urb		*urb,
+	struct fusbh200_iso_stream	*stream
+)
+{
+	u32			now, next, start, period, span;
+	int			status;
+	unsigned		mod = fusbh200->periodic_size << 3;
+	struct fusbh200_iso_sched	*sched = urb->hcpriv;
+
+	period = urb->interval;
+	span = sched->span;
+
+	if (span > mod - SCHEDULE_SLOP) {
+		fusbh200_dbg (fusbh200, "iso request %p too long\n", urb);
+		status = -EFBIG;
+		goto fail;
+	}
+
+	now = fusbh200_read_frame_index(fusbh200) & (mod - 1);
+
+	/* Typical case: reuse current schedule, stream is still active.
+	 * Hopefully there are no gaps from the host falling behind
+	 * (irq delays etc), but if there are we'll take the next
+	 * slot in the schedule, implicitly assuming URB_ISO_ASAP.
+	 */
+	if (likely (!list_empty (&stream->td_list))) {
+		u32	excess;
+
+		/* For high speed devices, allow scheduling within the
+		 * isochronous scheduling threshold.  For full speed devices
+		 * and Intel PCI-based controllers, don't (work around for
+		 * Intel ICH9 bug).
+		 */
+		if (!stream->highspeed && fusbh200->fs_i_thresh)
+			next = now + fusbh200->i_thresh;
+		else
+			next = now;
+
+		/* Fell behind (by up to twice the slop amount)?
+		 * We decide based on the time of the last currently-scheduled
+		 * slot, not the time of the next available slot.
+		 */
+		excess = (stream->next_uframe - period - next) & (mod - 1);
+		if (excess >= mod - 2 * SCHEDULE_SLOP)
+			start = next + excess - mod + period *
+					DIV_ROUND_UP(mod - excess, period);
+		else
+			start = next + excess + period;
+		if (start - now >= mod) {
+			fusbh200_dbg(fusbh200, "request %p would overflow (%d+%d >= %d)\n",
+					urb, start - now - period, period,
+					mod);
+			status = -EFBIG;
+			goto fail;
+		}
+	}
+
+	/* need to schedule; when's the next (u)frame we could start?
+	 * this is bigger than fusbh200->i_thresh allows; scheduling itself
+	 * isn't free, the slop should handle reasonably slow cpus.  it
+	 * can also help high bandwidth if the dma and irq loads don't
+	 * jump until after the queue is primed.
+	 */
+	else {
+		int done = 0;
+		start = SCHEDULE_SLOP + (now & ~0x07);
+
+		/* NOTE:  assumes URB_ISO_ASAP, to limit complexity/bugs */
+
+		/* find a uframe slot with enough bandwidth.
+		 * Early uframes are more precious because full-speed
+		 * iso IN transfers can't use late uframes,
+		 * and therefore they should be allocated last.
+		 */
+		next = start;
+		start += period;
+		do {
+			start--;
+			/* check schedule: enough space? */
+			if (itd_slot_ok(fusbh200, mod, start,
+					stream->usecs, period))
+				done = 1;
+		} while (start > next && !done);
+
+		/* no room in the schedule */
+		if (!done) {
+			fusbh200_dbg(fusbh200, "iso resched full %p (now %d max %d)\n",
+				urb, now, now + mod);
+			status = -ENOSPC;
+			goto fail;
+		}
+	}
+
+	/* Tried to schedule too far into the future? */
+	if (unlikely(start - now + span - period
+				>= mod - 2 * SCHEDULE_SLOP)) {
+		fusbh200_dbg(fusbh200, "request %p would overflow (%d+%d >= %d)\n",
+				urb, start - now, span - period,
+				mod - 2 * SCHEDULE_SLOP);
+		status = -EFBIG;
+		goto fail;
+	}
+
+	stream->next_uframe = start & (mod - 1);
+
+	/* report high speed start in uframes; full speed, in frames */
+	urb->start_frame = stream->next_uframe;
+	if (!stream->highspeed)
+		urb->start_frame >>= 3;
+
+	/* Make sure scan_isoc() sees these */
+	if (fusbh200->isoc_count == 0)
+		fusbh200->next_frame = now >> 3;
+	return 0;
+
+ fail:
+	iso_sched_free(stream, sched);
+	urb->hcpriv = NULL;
+	return status;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static inline void
+itd_init(struct fusbh200_hcd *fusbh200, struct fusbh200_iso_stream *stream,
+		struct fusbh200_itd *itd)
+{
+	int i;
+
+	/* it's been recently zeroed */
+	itd->hw_next = FUSBH200_LIST_END(fusbh200);
+	itd->hw_bufp [0] = stream->buf0;
+	itd->hw_bufp [1] = stream->buf1;
+	itd->hw_bufp [2] = stream->buf2;
+
+	for (i = 0; i < 8; i++)
+		itd->index[i] = -1;
+
+	/* All other fields are filled when scheduling */
+}
+
+static inline void
+itd_patch(
+	struct fusbh200_hcd		*fusbh200,
+	struct fusbh200_itd		*itd,
+	struct fusbh200_iso_sched	*iso_sched,
+	unsigned		index,
+	u16			uframe
+)
+{
+	struct fusbh200_iso_packet	*uf = &iso_sched->packet [index];
+	unsigned		pg = itd->pg;
+
+	// BUG_ON (pg == 6 && uf->cross);
+
+	uframe &= 0x07;
+	itd->index [uframe] = index;
+
+	itd->hw_transaction[uframe] = uf->transaction;
+	itd->hw_transaction[uframe] |= cpu_to_hc32(fusbh200, pg << 12);
+	itd->hw_bufp[pg] |= cpu_to_hc32(fusbh200, uf->bufp & ~(u32)0);
+	itd->hw_bufp_hi[pg] |= cpu_to_hc32(fusbh200, (u32)(uf->bufp >> 32));
+
+	/* iso_frame_desc[].offset must be strictly increasing */
+	if (unlikely (uf->cross)) {
+		u64	bufp = uf->bufp + 4096;
+
+		itd->pg = ++pg;
+		itd->hw_bufp[pg] |= cpu_to_hc32(fusbh200, bufp & ~(u32)0);
+		itd->hw_bufp_hi[pg] |= cpu_to_hc32(fusbh200, (u32)(bufp >> 32));
+	}
+}
+
+static inline void
+itd_link (struct fusbh200_hcd *fusbh200, unsigned frame, struct fusbh200_itd *itd)
+{
+	union fusbh200_shadow	*prev = &fusbh200->pshadow[frame];
+	__hc32			*hw_p = &fusbh200->periodic[frame];
+	union fusbh200_shadow	here = *prev;
+	__hc32			type = 0;
+
+	/* skip any iso nodes which might belong to previous microframes */
+	while (here.ptr) {
+		type = Q_NEXT_TYPE(fusbh200, *hw_p);
+		if (type == cpu_to_hc32(fusbh200, Q_TYPE_QH))
+			break;
+		prev = periodic_next_shadow(fusbh200, prev, type);
+		hw_p = shadow_next_periodic(fusbh200, &here, type);
+		here = *prev;
+	}
+
+	itd->itd_next = here;
+	itd->hw_next = *hw_p;
+	prev->itd = itd;
+	itd->frame = frame;
+	wmb ();
+	*hw_p = cpu_to_hc32(fusbh200, itd->itd_dma | Q_TYPE_ITD);
+}
+
+/* fit urb's itds into the selected schedule slot; activate as needed */
+static void itd_link_urb(
+	struct fusbh200_hcd		*fusbh200,
+	struct urb		*urb,
+	unsigned		mod,
+	struct fusbh200_iso_stream	*stream
+)
+{
+	int			packet;
+	unsigned		next_uframe, uframe, frame;
+	struct fusbh200_iso_sched	*iso_sched = urb->hcpriv;
+	struct fusbh200_itd		*itd;
+
+	next_uframe = stream->next_uframe & (mod - 1);
+
+	if (unlikely (list_empty(&stream->td_list))) {
+		fusbh200_to_hcd(fusbh200)->self.bandwidth_allocated
+				+= stream->bandwidth;
+		fusbh200_vdbg (fusbh200,
+			"schedule devp %s ep%d%s-iso period %d start %d.%d\n",
+			urb->dev->devpath, stream->bEndpointAddress & 0x0f,
+			(stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out",
+			urb->interval,
+			next_uframe >> 3, next_uframe & 0x7);
+	}
+
+	/* fill iTDs uframe by uframe */
+	for (packet = 0, itd = NULL; packet < urb->number_of_packets; ) {
+		if (itd == NULL) {
+			/* ASSERT:  we have all necessary itds */
+			// BUG_ON (list_empty (&iso_sched->td_list));
+
+			/* ASSERT:  no itds for this endpoint in this uframe */
+
+			itd = list_entry (iso_sched->td_list.next,
+					struct fusbh200_itd, itd_list);
+			list_move_tail (&itd->itd_list, &stream->td_list);
+			itd->stream = stream;
+			itd->urb = urb;
+			itd_init (fusbh200, stream, itd);
+		}
+
+		uframe = next_uframe & 0x07;
+		frame = next_uframe >> 3;
+
+		itd_patch(fusbh200, itd, iso_sched, packet, uframe);
+
+		next_uframe += stream->interval;
+		next_uframe &= mod - 1;
+		packet++;
+
+		/* link completed itds into the schedule */
+		if (((next_uframe >> 3) != frame)
+				|| packet == urb->number_of_packets) {
+			itd_link(fusbh200, frame & (fusbh200->periodic_size - 1), itd);
+			itd = NULL;
+		}
+	}
+	stream->next_uframe = next_uframe;
+
+	/* don't need that schedule data any more */
+	iso_sched_free (stream, iso_sched);
+	urb->hcpriv = NULL;
+
+	++fusbh200->isoc_count;
+	enable_periodic(fusbh200);
+}
+
+#define	ISO_ERRS (FUSBH200_ISOC_BUF_ERR | FUSBH200_ISOC_BABBLE | FUSBH200_ISOC_XACTERR)
+
+/* Process and recycle a completed ITD.  Return true iff its urb completed,
+ * and hence its completion callback probably added things to the hardware
+ * schedule.
+ *
+ * Note that we carefully avoid recycling this descriptor until after any
+ * completion callback runs, so that it won't be reused quickly.  That is,
+ * assuming (a) no more than two urbs per frame on this endpoint, and also
+ * (b) only this endpoint's completions submit URBs.  It seems some silicon
+ * corrupts things if you reuse completed descriptors very quickly...
+ */
+static bool itd_complete(struct fusbh200_hcd *fusbh200, struct fusbh200_itd *itd)
+{
+	struct urb				*urb = itd->urb;
+	struct usb_iso_packet_descriptor	*desc;
+	u32					t;
+	unsigned				uframe;
+	int					urb_index = -1;
+	struct fusbh200_iso_stream			*stream = itd->stream;
+	struct usb_device			*dev;
+	bool					retval = false;
+
+	/* for each uframe with a packet */
+	for (uframe = 0; uframe < 8; uframe++) {
+		if (likely (itd->index[uframe] == -1))
+			continue;
+		urb_index = itd->index[uframe];
+		desc = &urb->iso_frame_desc [urb_index];
+
+		t = hc32_to_cpup(fusbh200, &itd->hw_transaction [uframe]);
+		itd->hw_transaction [uframe] = 0;
+
+		/* report transfer status */
+		if (unlikely (t & ISO_ERRS)) {
+			urb->error_count++;
+			if (t & FUSBH200_ISOC_BUF_ERR)
+				desc->status = usb_pipein (urb->pipe)
+					? -ENOSR  /* hc couldn't read */
+					: -ECOMM; /* hc couldn't write */
+			else if (t & FUSBH200_ISOC_BABBLE)
+				desc->status = -EOVERFLOW;
+			else /* (t & FUSBH200_ISOC_XACTERR) */
+				desc->status = -EPROTO;
+
+			/* HC need not update length with this error */
+			if (!(t & FUSBH200_ISOC_BABBLE)) {
+				desc->actual_length = fusbh200_itdlen(urb, desc, t);
+				urb->actual_length += desc->actual_length;
+			}
+		} else if (likely ((t & FUSBH200_ISOC_ACTIVE) == 0)) {
+			desc->status = 0;
+			desc->actual_length = fusbh200_itdlen(urb, desc, t);
+			urb->actual_length += desc->actual_length;
+		} else {
+			/* URB was too late */
+			desc->status = -EXDEV;
+		}
+	}
+
+	/* handle completion now? */
+	if (likely ((urb_index + 1) != urb->number_of_packets))
+		goto done;
+
+	/* ASSERT: it's really the last itd for this urb
+	list_for_each_entry (itd, &stream->td_list, itd_list)
+		BUG_ON (itd->urb == urb);
+	 */
+
+	/* give urb back to the driver; completion often (re)submits */
+	dev = urb->dev;
+	fusbh200_urb_done(fusbh200, urb, 0);
+	retval = true;
+	urb = NULL;
+
+	--fusbh200->isoc_count;
+	disable_periodic(fusbh200);
+
+	if (unlikely(list_is_singular(&stream->td_list))) {
+		fusbh200_to_hcd(fusbh200)->self.bandwidth_allocated
+				-= stream->bandwidth;
+		fusbh200_vdbg (fusbh200,
+			"deschedule devp %s ep%d%s-iso\n",
+			dev->devpath, stream->bEndpointAddress & 0x0f,
+			(stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out");
+	}
+
+done:
+	itd->urb = NULL;
+
+	/* Add to the end of the free list for later reuse */
+	list_move_tail(&itd->itd_list, &stream->free_list);
+
+	/* Recycle the iTDs when the pipeline is empty (ep no longer in use) */
+	if (list_empty(&stream->td_list)) {
+		list_splice_tail_init(&stream->free_list,
+				&fusbh200->cached_itd_list);
+		start_free_itds(fusbh200);
+	}
+
+	return retval;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int itd_submit (struct fusbh200_hcd *fusbh200, struct urb *urb,
+	gfp_t mem_flags)
+{
+	int			status = -EINVAL;
+	unsigned long		flags;
+	struct fusbh200_iso_stream	*stream;
+
+	/* Get iso_stream head */
+	stream = iso_stream_find (fusbh200, urb);
+	if (unlikely (stream == NULL)) {
+		fusbh200_dbg (fusbh200, "can't get iso stream\n");
+		return -ENOMEM;
+	}
+	if (unlikely (urb->interval != stream->interval &&
+		      fusbh200_port_speed(fusbh200, 0) == USB_PORT_STAT_HIGH_SPEED)) {
+			fusbh200_dbg (fusbh200, "can't change iso interval %d --> %d\n",
+				stream->interval, urb->interval);
+			goto done;
+	}
+
+#ifdef FUSBH200_URB_TRACE
+	fusbh200_dbg (fusbh200,
+		"%s %s urb %p ep%d%s len %d, %d pkts %d uframes [%p]\n",
+		__func__, urb->dev->devpath, urb,
+		usb_pipeendpoint (urb->pipe),
+		usb_pipein (urb->pipe) ? "in" : "out",
+		urb->transfer_buffer_length,
+		urb->number_of_packets, urb->interval,
+		stream);
+#endif
+
+	/* allocate ITDs w/o locking anything */
+	status = itd_urb_transaction (stream, fusbh200, urb, mem_flags);
+	if (unlikely (status < 0)) {
+		fusbh200_dbg (fusbh200, "can't init itds\n");
+		goto done;
+	}
+
+	/* schedule ... need to lock */
+	spin_lock_irqsave (&fusbh200->lock, flags);
+	if (unlikely(!HCD_HW_ACCESSIBLE(fusbh200_to_hcd(fusbh200)))) {
+		status = -ESHUTDOWN;
+		goto done_not_linked;
+	}
+	status = usb_hcd_link_urb_to_ep(fusbh200_to_hcd(fusbh200), urb);
+	if (unlikely(status))
+		goto done_not_linked;
+	status = iso_stream_schedule(fusbh200, urb, stream);
+	if (likely (status == 0))
+		itd_link_urb (fusbh200, urb, fusbh200->periodic_size << 3, stream);
+	else
+		usb_hcd_unlink_urb_from_ep(fusbh200_to_hcd(fusbh200), urb);
+ done_not_linked:
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+ done:
+	return status;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void scan_isoc(struct fusbh200_hcd *fusbh200)
+{
+	unsigned	uf, now_frame, frame;
+	unsigned	fmask = fusbh200->periodic_size - 1;
+	bool		modified, live;
+
+	/*
+	 * When running, scan from last scan point up to "now"
+	 * else clean up by scanning everything that's left.
+	 * Touches as few pages as possible:  cache-friendly.
+	 */
+	if (fusbh200->rh_state >= FUSBH200_RH_RUNNING) {
+		uf = fusbh200_read_frame_index(fusbh200);
+		now_frame = (uf >> 3) & fmask;
+		live = true;
+	} else  {
+		now_frame = (fusbh200->next_frame - 1) & fmask;
+		live = false;
+	}
+	fusbh200->now_frame = now_frame;
+
+	frame = fusbh200->next_frame;
+	for (;;) {
+		union fusbh200_shadow	q, *q_p;
+		__hc32			type, *hw_p;
+
+restart:
+		/* scan each element in frame's queue for completions */
+		q_p = &fusbh200->pshadow [frame];
+		hw_p = &fusbh200->periodic [frame];
+		q.ptr = q_p->ptr;
+		type = Q_NEXT_TYPE(fusbh200, *hw_p);
+		modified = false;
+
+		while (q.ptr != NULL) {
+			switch (hc32_to_cpu(fusbh200, type)) {
+			case Q_TYPE_ITD:
+				/* If this ITD is still active, leave it for
+				 * later processing ... check the next entry.
+				 * No need to check for activity unless the
+				 * frame is current.
+				 */
+				if (frame == now_frame && live) {
+					rmb();
+					for (uf = 0; uf < 8; uf++) {
+						if (q.itd->hw_transaction[uf] &
+							    ITD_ACTIVE(fusbh200))
+							break;
+					}
+					if (uf < 8) {
+						q_p = &q.itd->itd_next;
+						hw_p = &q.itd->hw_next;
+						type = Q_NEXT_TYPE(fusbh200,
+							q.itd->hw_next);
+						q = *q_p;
+						break;
+					}
+				}
+
+				/* Take finished ITDs out of the schedule
+				 * and process them:  recycle, maybe report
+				 * URB completion.  HC won't cache the
+				 * pointer for much longer, if at all.
+				 */
+				*q_p = q.itd->itd_next;
+				*hw_p = q.itd->hw_next;
+				type = Q_NEXT_TYPE(fusbh200, q.itd->hw_next);
+				wmb();
+				modified = itd_complete (fusbh200, q.itd);
+				q = *q_p;
+				break;
+			default:
+				fusbh200_dbg(fusbh200, "corrupt type %d frame %d shadow %p\n",
+					type, frame, q.ptr);
+				// BUG ();
+				/* FALL THROUGH */
+			case Q_TYPE_QH:
+			case Q_TYPE_FSTN:
+				/* End of the iTDs and siTDs */
+				q.ptr = NULL;
+				break;
+			}
+
+			/* assume completion callbacks modify the queue */
+			if (unlikely(modified && fusbh200->isoc_count > 0))
+				goto restart;
+		}
+
+		/* Stop when we have reached the current frame */
+		if (frame == now_frame)
+			break;
+		frame = (frame + 1) & fmask;
+	}
+	fusbh200->next_frame = now_frame;
+}
+/*-------------------------------------------------------------------------*/
+/*
+ * Display / Set uframe_periodic_max
+ */
+static ssize_t show_uframe_periodic_max(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct fusbh200_hcd		*fusbh200;
+	int			n;
+
+	fusbh200 = hcd_to_fusbh200(bus_to_hcd(dev_get_drvdata(dev)));
+	n = scnprintf(buf, PAGE_SIZE, "%d\n", fusbh200->uframe_periodic_max);
+	return n;
+}
+
+
+static ssize_t store_uframe_periodic_max(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct fusbh200_hcd		*fusbh200;
+	unsigned		uframe_periodic_max;
+	unsigned		frame, uframe;
+	unsigned short		allocated_max;
+	unsigned long		flags;
+	ssize_t			ret;
+
+	fusbh200 = hcd_to_fusbh200(bus_to_hcd(dev_get_drvdata(dev)));
+	if (kstrtouint(buf, 0, &uframe_periodic_max) < 0)
+		return -EINVAL;
+
+	if (uframe_periodic_max < 100 || uframe_periodic_max >= 125) {
+		fusbh200_info(fusbh200, "rejecting invalid request for "
+				"uframe_periodic_max=%u\n", uframe_periodic_max);
+		return -EINVAL;
+	}
+
+	ret = -EINVAL;
+
+	/*
+	 * lock, so that our checking does not race with possible periodic
+	 * bandwidth allocation through submitting new urbs.
+	 */
+	spin_lock_irqsave (&fusbh200->lock, flags);
+
+	/*
+	 * for request to decrease max periodic bandwidth, we have to check
+	 * every microframe in the schedule to see whether the decrease is
+	 * possible.
+	 */
+	if (uframe_periodic_max < fusbh200->uframe_periodic_max) {
+		allocated_max = 0;
+
+		for (frame = 0; frame < fusbh200->periodic_size; ++frame)
+			for (uframe = 0; uframe < 7; ++uframe)
+				allocated_max = max(allocated_max,
+						    periodic_usecs (fusbh200, frame, uframe));
+
+		if (allocated_max > uframe_periodic_max) {
+			fusbh200_info(fusbh200,
+				"cannot decrease uframe_periodic_max becase "
+				"periodic bandwidth is already allocated "
+				"(%u > %u)\n",
+				allocated_max, uframe_periodic_max);
+			goto out_unlock;
+		}
+	}
+
+	/* increasing is always ok */
+
+	fusbh200_info(fusbh200, "setting max periodic bandwidth to %u%% "
+			"(== %u usec/uframe)\n",
+			100*uframe_periodic_max/125, uframe_periodic_max);
+
+	if (uframe_periodic_max != 100)
+		fusbh200_warn(fusbh200, "max periodic bandwidth set is non-standard\n");
+
+	fusbh200->uframe_periodic_max = uframe_periodic_max;
+	ret = count;
+
+out_unlock:
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+	return ret;
+}
+static DEVICE_ATTR(uframe_periodic_max, 0644, show_uframe_periodic_max, store_uframe_periodic_max);
+
+
+static inline int create_sysfs_files(struct fusbh200_hcd *fusbh200)
+{
+	struct device	*controller = fusbh200_to_hcd(fusbh200)->self.controller;
+	int	i = 0;
+
+	if (i)
+		goto out;
+
+	i = device_create_file(controller, &dev_attr_uframe_periodic_max);
+out:
+	return i;
+}
+
+static inline void remove_sysfs_files(struct fusbh200_hcd *fusbh200)
+{
+	struct device	*controller = fusbh200_to_hcd(fusbh200)->self.controller;
+
+	device_remove_file(controller, &dev_attr_uframe_periodic_max);
+}
+/*-------------------------------------------------------------------------*/
+
+/* On some systems, leaving remote wakeup enabled prevents system shutdown.
+ * The firmware seems to think that powering off is a wakeup event!
+ * This routine turns off remote wakeup and everything else, on all ports.
+ */
+static void fusbh200_turn_off_all_ports(struct fusbh200_hcd *fusbh200)
+{
+	u32 __iomem *status_reg = &fusbh200->regs->port_status;
+
+	fusbh200_writel(fusbh200, PORT_RWC_BITS, status_reg);
+}
+
+/*
+ * Halt HC, turn off all ports, and let the BIOS use the companion controllers.
+ * Must be called with interrupts enabled and the lock not held.
+ */
+static void fusbh200_silence_controller(struct fusbh200_hcd *fusbh200)
+{
+	fusbh200_halt(fusbh200);
+
+	spin_lock_irq(&fusbh200->lock);
+	fusbh200->rh_state = FUSBH200_RH_HALTED;
+	fusbh200_turn_off_all_ports(fusbh200);
+	spin_unlock_irq(&fusbh200->lock);
+}
+
+/* fusbh200_shutdown kick in for silicon on any bus (not just pci, etc).
+ * This forcibly disables dma and IRQs, helping kexec and other cases
+ * where the next system software may expect clean state.
+ */
+static void fusbh200_shutdown(struct usb_hcd *hcd)
+{
+	struct fusbh200_hcd	*fusbh200 = hcd_to_fusbh200(hcd);
+
+	spin_lock_irq(&fusbh200->lock);
+	fusbh200->shutdown = true;
+	fusbh200->rh_state = FUSBH200_RH_STOPPING;
+	fusbh200->enabled_hrtimer_events = 0;
+	spin_unlock_irq(&fusbh200->lock);
+
+	fusbh200_silence_controller(fusbh200);
+
+	hrtimer_cancel(&fusbh200->hrtimer);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * fusbh200_work is called from some interrupts, timers, and so on.
+ * it calls driver completion functions, after dropping fusbh200->lock.
+ */
+static void fusbh200_work (struct fusbh200_hcd *fusbh200)
+{
+	/* another CPU may drop fusbh200->lock during a schedule scan while
+	 * it reports urb completions.  this flag guards against bogus
+	 * attempts at re-entrant schedule scanning.
+	 */
+	if (fusbh200->scanning) {
+		fusbh200->need_rescan = true;
+		return;
+	}
+	fusbh200->scanning = true;
+
+ rescan:
+	fusbh200->need_rescan = false;
+	if (fusbh200->async_count)
+		scan_async(fusbh200);
+	if (fusbh200->intr_count > 0)
+		scan_intr(fusbh200);
+	if (fusbh200->isoc_count > 0)
+		scan_isoc(fusbh200);
+	if (fusbh200->need_rescan)
+		goto rescan;
+	fusbh200->scanning = false;
+
+	/* the IO watchdog guards against hardware or driver bugs that
+	 * misplace IRQs, and should let us run completely without IRQs.
+	 * such lossage has been observed on both VT6202 and VT8235.
+	 */
+	turn_on_io_watchdog(fusbh200);
+}
+
+/*
+ * Called when the fusbh200_hcd module is removed.
+ */
+static void fusbh200_stop (struct usb_hcd *hcd)
+{
+	struct fusbh200_hcd		*fusbh200 = hcd_to_fusbh200 (hcd);
+
+	fusbh200_dbg (fusbh200, "stop\n");
+
+	/* no more interrupts ... */
+
+	spin_lock_irq(&fusbh200->lock);
+	fusbh200->enabled_hrtimer_events = 0;
+	spin_unlock_irq(&fusbh200->lock);
+
+	fusbh200_quiesce(fusbh200);
+	fusbh200_silence_controller(fusbh200);
+	fusbh200_reset (fusbh200);
+
+	hrtimer_cancel(&fusbh200->hrtimer);
+	remove_sysfs_files(fusbh200);
+	remove_debug_files (fusbh200);
+
+	/* root hub is shut down separately (first, when possible) */
+	spin_lock_irq (&fusbh200->lock);
+	end_free_itds(fusbh200);
+	spin_unlock_irq (&fusbh200->lock);
+	fusbh200_mem_cleanup (fusbh200);
+
+#ifdef	FUSBH200_STATS
+	fusbh200_dbg(fusbh200, "irq normal %ld err %ld iaa %ld (lost %ld)\n",
+		fusbh200->stats.normal, fusbh200->stats.error, fusbh200->stats.iaa,
+		fusbh200->stats.lost_iaa);
+	fusbh200_dbg (fusbh200, "complete %ld unlink %ld\n",
+		fusbh200->stats.complete, fusbh200->stats.unlink);
+#endif
+
+	dbg_status (fusbh200, "fusbh200_stop completed",
+		    fusbh200_readl(fusbh200, &fusbh200->regs->status));
+}
+
+/* one-time init, only for memory state */
+static int hcd_fusbh200_init(struct usb_hcd *hcd)
+{
+	struct fusbh200_hcd		*fusbh200 = hcd_to_fusbh200(hcd);
+	u32			temp;
+	int			retval;
+	u32			hcc_params;
+	struct fusbh200_qh_hw	*hw;
+
+	spin_lock_init(&fusbh200->lock);
+
+	/*
+	 * keep io watchdog by default, those good HCDs could turn off it later
+	 */
+	fusbh200->need_io_watchdog = 1;
+
+	hrtimer_init(&fusbh200->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+	fusbh200->hrtimer.function = fusbh200_hrtimer_func;
+	fusbh200->next_hrtimer_event = FUSBH200_HRTIMER_NO_EVENT;
+
+	hcc_params = fusbh200_readl(fusbh200, &fusbh200->caps->hcc_params);
+
+	/*
+	 * by default set standard 80% (== 100 usec/uframe) max periodic
+	 * bandwidth as required by USB 2.0
+	 */
+	fusbh200->uframe_periodic_max = 100;
+
+	/*
+	 * hw default: 1K periodic list heads, one per frame.
+	 * periodic_size can shrink by USBCMD update if hcc_params allows.
+	 */
+	fusbh200->periodic_size = DEFAULT_I_TDPS;
+	INIT_LIST_HEAD(&fusbh200->intr_qh_list);
+	INIT_LIST_HEAD(&fusbh200->cached_itd_list);
+
+	if (HCC_PGM_FRAMELISTLEN(hcc_params)) {
+		/* periodic schedule size can be smaller than default */
+		switch (FUSBH200_TUNE_FLS) {
+		case 0: fusbh200->periodic_size = 1024; break;
+		case 1: fusbh200->periodic_size = 512; break;
+		case 2: fusbh200->periodic_size = 256; break;
+		default:	BUG();
+		}
+	}
+	if ((retval = fusbh200_mem_init(fusbh200, GFP_KERNEL)) < 0)
+		return retval;
+
+	/* controllers may cache some of the periodic schedule ... */
+	fusbh200->i_thresh = 2;
+
+	/*
+	 * dedicate a qh for the async ring head, since we couldn't unlink
+	 * a 'real' qh without stopping the async schedule [4.8].  use it
+	 * as the 'reclamation list head' too.
+	 * its dummy is used in hw_alt_next of many tds, to prevent the qh
+	 * from automatically advancing to the next td after short reads.
+	 */
+	fusbh200->async->qh_next.qh = NULL;
+	hw = fusbh200->async->hw;
+	hw->hw_next = QH_NEXT(fusbh200, fusbh200->async->qh_dma);
+	hw->hw_info1 = cpu_to_hc32(fusbh200, QH_HEAD);
+	hw->hw_token = cpu_to_hc32(fusbh200, QTD_STS_HALT);
+	hw->hw_qtd_next = FUSBH200_LIST_END(fusbh200);
+	fusbh200->async->qh_state = QH_STATE_LINKED;
+	hw->hw_alt_next = QTD_NEXT(fusbh200, fusbh200->async->dummy->qtd_dma);
+
+	/* clear interrupt enables, set irq latency */
+	if (log2_irq_thresh < 0 || log2_irq_thresh > 6)
+		log2_irq_thresh = 0;
+	temp = 1 << (16 + log2_irq_thresh);
+	if (HCC_CANPARK(hcc_params)) {
+		/* HW default park == 3, on hardware that supports it (like
+		 * NVidia and ALI silicon), maximizes throughput on the async
+		 * schedule by avoiding QH fetches between transfers.
+		 *
+		 * With fast usb storage devices and NForce2, "park" seems to
+		 * make problems:  throughput reduction (!), data errors...
+		 */
+		if (park) {
+			park = min(park, (unsigned) 3);
+			temp |= CMD_PARK;
+			temp |= park << 8;
+		}
+		fusbh200_dbg(fusbh200, "park %d\n", park);
+	}
+	if (HCC_PGM_FRAMELISTLEN(hcc_params)) {
+		/* periodic schedule size can be smaller than default */
+		temp &= ~(3 << 2);
+		temp |= (FUSBH200_TUNE_FLS << 2);
+	}
+	fusbh200->command = temp;
+
+	/* Accept arbitrarily long scatter-gather lists */
+	if (!(hcd->driver->flags & HCD_LOCAL_MEM))
+		hcd->self.sg_tablesize = ~0;
+	return 0;
+}
+
+/* start HC running; it's halted, hcd_fusbh200_init() has been run (once) */
+static int fusbh200_run (struct usb_hcd *hcd)
+{
+	struct fusbh200_hcd		*fusbh200 = hcd_to_fusbh200 (hcd);
+	u32			temp;
+	u32			hcc_params;
+
+	hcd->uses_new_polling = 1;
+
+	/* EHCI spec section 4.1 */
+
+	fusbh200_writel(fusbh200, fusbh200->periodic_dma, &fusbh200->regs->frame_list);
+	fusbh200_writel(fusbh200, (u32)fusbh200->async->qh_dma, &fusbh200->regs->async_next);
+
+	/*
+	 * hcc_params controls whether fusbh200->regs->segment must (!!!)
+	 * be used; it constrains QH/ITD/SITD and QTD locations.
+	 * pci_pool consistent memory always uses segment zero.
+	 * streaming mappings for I/O buffers, like pci_map_single(),
+	 * can return segments above 4GB, if the device allows.
+	 *
+	 * NOTE:  the dma mask is visible through dma_supported(), so
+	 * drivers can pass this info along ... like NETIF_F_HIGHDMA,
+	 * Scsi_Host.highmem_io, and so forth.  It's readonly to all
+	 * host side drivers though.
+	 */
+	hcc_params = fusbh200_readl(fusbh200, &fusbh200->caps->hcc_params);
+
+	// Philips, Intel, and maybe others need CMD_RUN before the
+	// root hub will detect new devices (why?); NEC doesn't
+	fusbh200->command &= ~(CMD_IAAD|CMD_PSE|CMD_ASE|CMD_RESET);
+	fusbh200->command |= CMD_RUN;
+	fusbh200_writel(fusbh200, fusbh200->command, &fusbh200->regs->command);
+	dbg_cmd (fusbh200, "init", fusbh200->command);
+
+	/*
+	 * Start, enabling full USB 2.0 functionality ... usb 1.1 devices
+	 * are explicitly handed to companion controller(s), so no TT is
+	 * involved with the root hub.  (Except where one is integrated,
+	 * and there's no companion controller unless maybe for USB OTG.)
+	 *
+	 * Turning on the CF flag will transfer ownership of all ports
+	 * from the companions to the EHCI controller.  If any of the
+	 * companions are in the middle of a port reset at the time, it
+	 * could cause trouble.  Write-locking ehci_cf_port_reset_rwsem
+	 * guarantees that no resets are in progress.  After we set CF,
+	 * a short delay lets the hardware catch up; new resets shouldn't
+	 * be started before the port switching actions could complete.
+	 */
+	down_write(&ehci_cf_port_reset_rwsem);
+	fusbh200->rh_state = FUSBH200_RH_RUNNING;
+	fusbh200_readl(fusbh200, &fusbh200->regs->command);	/* unblock posted writes */
+	msleep(5);
+	up_write(&ehci_cf_port_reset_rwsem);
+	fusbh200->last_periodic_enable = ktime_get_real();
+
+	temp = HC_VERSION(fusbh200, fusbh200_readl(fusbh200, &fusbh200->caps->hc_capbase));
+	fusbh200_info (fusbh200,
+		"USB %x.%x started, EHCI %x.%02x\n",
+		((fusbh200->sbrn & 0xf0)>>4), (fusbh200->sbrn & 0x0f),
+		temp >> 8, temp & 0xff);
+
+	fusbh200_writel(fusbh200, INTR_MASK,
+		    &fusbh200->regs->intr_enable); /* Turn On Interrupts */
+
+	/* GRR this is run-once init(), being done every time the HC starts.
+	 * So long as they're part of class devices, we can't do it init()
+	 * since the class device isn't created that early.
+	 */
+	create_debug_files(fusbh200);
+	create_sysfs_files(fusbh200);
+
+	return 0;
+}
+
+static int fusbh200_setup(struct usb_hcd *hcd)
+{
+	struct fusbh200_hcd *fusbh200 = hcd_to_fusbh200(hcd);
+	int retval;
+
+	fusbh200->regs = (void __iomem *)fusbh200->caps +
+	    HC_LENGTH(fusbh200, fusbh200_readl(fusbh200, &fusbh200->caps->hc_capbase));
+	dbg_hcs_params(fusbh200, "reset");
+	dbg_hcc_params(fusbh200, "reset");
+
+	/* cache this readonly data; minimize chip reads */
+	fusbh200->hcs_params = fusbh200_readl(fusbh200, &fusbh200->caps->hcs_params);
+
+	fusbh200->sbrn = HCD_USB2;
+
+	/* data structure init */
+	retval = hcd_fusbh200_init(hcd);
+	if (retval)
+		return retval;
+
+	retval = fusbh200_halt(fusbh200);
+	if (retval)
+		return retval;
+
+	fusbh200_reset(fusbh200);
+
+	return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static irqreturn_t fusbh200_irq (struct usb_hcd *hcd)
+{
+	struct fusbh200_hcd		*fusbh200 = hcd_to_fusbh200 (hcd);
+	u32			status, masked_status, pcd_status = 0, cmd;
+	int			bh;
+
+	spin_lock (&fusbh200->lock);
+
+	status = fusbh200_readl(fusbh200, &fusbh200->regs->status);
+
+	/* e.g. cardbus physical eject */
+	if (status == ~(u32) 0) {
+		fusbh200_dbg (fusbh200, "device removed\n");
+		goto dead;
+	}
+
+	/*
+	 * We don't use STS_FLR, but some controllers don't like it to
+	 * remain on, so mask it out along with the other status bits.
+	 */
+	masked_status = status & (INTR_MASK | STS_FLR);
+
+	/* Shared IRQ? */
+	if (!masked_status || unlikely(fusbh200->rh_state == FUSBH200_RH_HALTED)) {
+		spin_unlock(&fusbh200->lock);
+		return IRQ_NONE;
+	}
+
+	/* clear (just) interrupts */
+	fusbh200_writel(fusbh200, masked_status, &fusbh200->regs->status);
+	cmd = fusbh200_readl(fusbh200, &fusbh200->regs->command);
+	bh = 0;
+
+#ifdef	VERBOSE_DEBUG
+	/* unrequested/ignored: Frame List Rollover */
+	dbg_status (fusbh200, "irq", status);
+#endif
+
+	/* INT, ERR, and IAA interrupt rates can be throttled */
+
+	/* normal [4.15.1.2] or error [4.15.1.1] completion */
+	if (likely ((status & (STS_INT|STS_ERR)) != 0)) {
+		if (likely ((status & STS_ERR) == 0))
+			COUNT (fusbh200->stats.normal);
+		else
+			COUNT (fusbh200->stats.error);
+		bh = 1;
+	}
+
+	/* complete the unlinking of some qh [4.15.2.3] */
+	if (status & STS_IAA) {
+
+		/* Turn off the IAA watchdog */
+		fusbh200->enabled_hrtimer_events &= ~BIT(FUSBH200_HRTIMER_IAA_WATCHDOG);
+
+		/*
+		 * Mild optimization: Allow another IAAD to reset the
+		 * hrtimer, if one occurs before the next expiration.
+		 * In theory we could always cancel the hrtimer, but
+		 * tests show that about half the time it will be reset
+		 * for some other event anyway.
+		 */
+		if (fusbh200->next_hrtimer_event == FUSBH200_HRTIMER_IAA_WATCHDOG)
+			++fusbh200->next_hrtimer_event;
+
+		/* guard against (alleged) silicon errata */
+		if (cmd & CMD_IAAD)
+			fusbh200_dbg(fusbh200, "IAA with IAAD still set?\n");
+		if (fusbh200->async_iaa) {
+			COUNT(fusbh200->stats.iaa);
+			end_unlink_async(fusbh200);
+		} else
+			fusbh200_dbg(fusbh200, "IAA with nothing unlinked?\n");
+	}
+
+	/* remote wakeup [4.3.1] */
+	if (status & STS_PCD) {
+		int pstatus;
+		u32 __iomem *status_reg = &fusbh200->regs->port_status;
+
+		/* kick root hub later */
+		pcd_status = status;
+
+		/* resume root hub? */
+		if (fusbh200->rh_state == FUSBH200_RH_SUSPENDED)
+			usb_hcd_resume_root_hub(hcd);
+
+		pstatus = fusbh200_readl(fusbh200, status_reg);
+
+		if (test_bit(0, &fusbh200->suspended_ports) &&
+				((pstatus & PORT_RESUME) ||
+					!(pstatus & PORT_SUSPEND)) &&
+				(pstatus & PORT_PE) &&
+				fusbh200->reset_done[0] == 0) {
+
+			/* start 20 msec resume signaling from this port,
+			 * and make khubd collect PORT_STAT_C_SUSPEND to
+			 * stop that signaling.  Use 5 ms extra for safety,
+			 * like usb_port_resume() does.
+			 */
+			fusbh200->reset_done[0] = jiffies + msecs_to_jiffies(25);
+			set_bit(0, &fusbh200->resuming_ports);
+			fusbh200_dbg (fusbh200, "port 1 remote wakeup\n");
+			mod_timer(&hcd->rh_timer, fusbh200->reset_done[0]);
+		}
+	}
+
+	/* PCI errors [4.15.2.4] */
+	if (unlikely ((status & STS_FATAL) != 0)) {
+		fusbh200_err(fusbh200, "fatal error\n");
+		dbg_cmd(fusbh200, "fatal", cmd);
+		dbg_status(fusbh200, "fatal", status);
+dead:
+		usb_hc_died(hcd);
+
+		/* Don't let the controller do anything more */
+		fusbh200->shutdown = true;
+		fusbh200->rh_state = FUSBH200_RH_STOPPING;
+		fusbh200->command &= ~(CMD_RUN | CMD_ASE | CMD_PSE);
+		fusbh200_writel(fusbh200, fusbh200->command, &fusbh200->regs->command);
+		fusbh200_writel(fusbh200, 0, &fusbh200->regs->intr_enable);
+		fusbh200_handle_controller_death(fusbh200);
+
+		/* Handle completions when the controller stops */
+		bh = 0;
+	}
+
+	if (bh)
+		fusbh200_work (fusbh200);
+	spin_unlock (&fusbh200->lock);
+	if (pcd_status)
+		usb_hcd_poll_rh_status(hcd);
+	return IRQ_HANDLED;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * non-error returns are a promise to giveback() the urb later
+ * we drop ownership so next owner (or urb unlink) can get it
+ *
+ * urb + dev is in hcd.self.controller.urb_list
+ * we're queueing TDs onto software and hardware lists
+ *
+ * hcd-specific init for hcpriv hasn't been done yet
+ *
+ * NOTE:  control, bulk, and interrupt share the same code to append TDs
+ * to a (possibly active) QH, and the same QH scanning code.
+ */
+static int fusbh200_urb_enqueue (
+	struct usb_hcd	*hcd,
+	struct urb	*urb,
+	gfp_t		mem_flags
+) {
+	struct fusbh200_hcd		*fusbh200 = hcd_to_fusbh200 (hcd);
+	struct list_head	qtd_list;
+
+	INIT_LIST_HEAD (&qtd_list);
+
+	switch (usb_pipetype (urb->pipe)) {
+	case PIPE_CONTROL:
+		/* qh_completions() code doesn't handle all the fault cases
+		 * in multi-TD control transfers.  Even 1KB is rare anyway.
+		 */
+		if (urb->transfer_buffer_length > (16 * 1024))
+			return -EMSGSIZE;
+		/* FALLTHROUGH */
+	/* case PIPE_BULK: */
+	default:
+		if (!qh_urb_transaction (fusbh200, urb, &qtd_list, mem_flags))
+			return -ENOMEM;
+		return submit_async(fusbh200, urb, &qtd_list, mem_flags);
+
+	case PIPE_INTERRUPT:
+		if (!qh_urb_transaction (fusbh200, urb, &qtd_list, mem_flags))
+			return -ENOMEM;
+		return intr_submit(fusbh200, urb, &qtd_list, mem_flags);
+
+	case PIPE_ISOCHRONOUS:
+		return itd_submit (fusbh200, urb, mem_flags);
+	}
+}
+
+/* remove from hardware lists
+ * completions normally happen asynchronously
+ */
+
+static int fusbh200_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
+{
+	struct fusbh200_hcd		*fusbh200 = hcd_to_fusbh200 (hcd);
+	struct fusbh200_qh		*qh;
+	unsigned long		flags;
+	int			rc;
+
+	spin_lock_irqsave (&fusbh200->lock, flags);
+	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
+	if (rc)
+		goto done;
+
+	switch (usb_pipetype (urb->pipe)) {
+	// case PIPE_CONTROL:
+	// case PIPE_BULK:
+	default:
+		qh = (struct fusbh200_qh *) urb->hcpriv;
+		if (!qh)
+			break;
+		switch (qh->qh_state) {
+		case QH_STATE_LINKED:
+		case QH_STATE_COMPLETING:
+			start_unlink_async(fusbh200, qh);
+			break;
+		case QH_STATE_UNLINK:
+		case QH_STATE_UNLINK_WAIT:
+			/* already started */
+			break;
+		case QH_STATE_IDLE:
+			/* QH might be waiting for a Clear-TT-Buffer */
+			qh_completions(fusbh200, qh);
+			break;
+		}
+		break;
+
+	case PIPE_INTERRUPT:
+		qh = (struct fusbh200_qh *) urb->hcpriv;
+		if (!qh)
+			break;
+		switch (qh->qh_state) {
+		case QH_STATE_LINKED:
+		case QH_STATE_COMPLETING:
+			start_unlink_intr(fusbh200, qh);
+			break;
+		case QH_STATE_IDLE:
+			qh_completions (fusbh200, qh);
+			break;
+		default:
+			fusbh200_dbg (fusbh200, "bogus qh %p state %d\n",
+					qh, qh->qh_state);
+			goto done;
+		}
+		break;
+
+	case PIPE_ISOCHRONOUS:
+		// itd...
+
+		// wait till next completion, do it then.
+		// completion irqs can wait up to 1024 msec,
+		break;
+	}
+done:
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+	return rc;
+}
+
+/*-------------------------------------------------------------------------*/
+
+// bulk qh holds the data toggle
+
+static void
+fusbh200_endpoint_disable (struct usb_hcd *hcd, struct usb_host_endpoint *ep)
+{
+	struct fusbh200_hcd		*fusbh200 = hcd_to_fusbh200 (hcd);
+	unsigned long		flags;
+	struct fusbh200_qh		*qh, *tmp;
+
+	/* ASSERT:  any requests/urbs are being unlinked */
+	/* ASSERT:  nobody can be submitting urbs for this any more */
+
+rescan:
+	spin_lock_irqsave (&fusbh200->lock, flags);
+	qh = ep->hcpriv;
+	if (!qh)
+		goto done;
+
+	/* endpoints can be iso streams.  for now, we don't
+	 * accelerate iso completions ... so spin a while.
+	 */
+	if (qh->hw == NULL) {
+		struct fusbh200_iso_stream	*stream = ep->hcpriv;
+
+		if (!list_empty(&stream->td_list))
+			goto idle_timeout;
+
+		/* BUG_ON(!list_empty(&stream->free_list)); */
+		kfree(stream);
+		goto done;
+	}
+
+	if (fusbh200->rh_state < FUSBH200_RH_RUNNING)
+		qh->qh_state = QH_STATE_IDLE;
+	switch (qh->qh_state) {
+	case QH_STATE_LINKED:
+	case QH_STATE_COMPLETING:
+		for (tmp = fusbh200->async->qh_next.qh;
+				tmp && tmp != qh;
+				tmp = tmp->qh_next.qh)
+			continue;
+		/* periodic qh self-unlinks on empty, and a COMPLETING qh
+		 * may already be unlinked.
+		 */
+		if (tmp)
+			start_unlink_async(fusbh200, qh);
+		/* FALL THROUGH */
+	case QH_STATE_UNLINK:		/* wait for hw to finish? */
+	case QH_STATE_UNLINK_WAIT:
+idle_timeout:
+		spin_unlock_irqrestore (&fusbh200->lock, flags);
+		schedule_timeout_uninterruptible(1);
+		goto rescan;
+	case QH_STATE_IDLE:		/* fully unlinked */
+		if (qh->clearing_tt)
+			goto idle_timeout;
+		if (list_empty (&qh->qtd_list)) {
+			qh_destroy(fusbh200, qh);
+			break;
+		}
+		/* else FALL THROUGH */
+	default:
+		/* caller was supposed to have unlinked any requests;
+		 * that's not our job.  just leak this memory.
+		 */
+		fusbh200_err (fusbh200, "qh %p (#%02x) state %d%s\n",
+			qh, ep->desc.bEndpointAddress, qh->qh_state,
+			list_empty (&qh->qtd_list) ? "" : "(has tds)");
+		break;
+	}
+ done:
+	ep->hcpriv = NULL;
+	spin_unlock_irqrestore (&fusbh200->lock, flags);
+}
+
+static void
+fusbh200_endpoint_reset(struct usb_hcd *hcd, struct usb_host_endpoint *ep)
+{
+	struct fusbh200_hcd		*fusbh200 = hcd_to_fusbh200(hcd);
+	struct fusbh200_qh		*qh;
+	int			eptype = usb_endpoint_type(&ep->desc);
+	int			epnum = usb_endpoint_num(&ep->desc);
+	int			is_out = usb_endpoint_dir_out(&ep->desc);
+	unsigned long		flags;
+
+	if (eptype != USB_ENDPOINT_XFER_BULK && eptype != USB_ENDPOINT_XFER_INT)
+		return;
+
+	spin_lock_irqsave(&fusbh200->lock, flags);
+	qh = ep->hcpriv;
+
+	/* For Bulk and Interrupt endpoints we maintain the toggle state
+	 * in the hardware; the toggle bits in udev aren't used at all.
+	 * When an endpoint is reset by usb_clear_halt() we must reset
+	 * the toggle bit in the QH.
+	 */
+	if (qh) {
+		usb_settoggle(qh->dev, epnum, is_out, 0);
+		if (!list_empty(&qh->qtd_list)) {
+			WARN_ONCE(1, "clear_halt for a busy endpoint\n");
+		} else if (qh->qh_state == QH_STATE_LINKED ||
+				qh->qh_state == QH_STATE_COMPLETING) {
+
+			/* The toggle value in the QH can't be updated
+			 * while the QH is active.  Unlink it now;
+			 * re-linking will call qh_refresh().
+			 */
+			if (eptype == USB_ENDPOINT_XFER_BULK)
+				start_unlink_async(fusbh200, qh);
+			else
+				start_unlink_intr(fusbh200, qh);
+		}
+	}
+	spin_unlock_irqrestore(&fusbh200->lock, flags);
+}
+
+static int fusbh200_get_frame (struct usb_hcd *hcd)
+{
+	struct fusbh200_hcd		*fusbh200 = hcd_to_fusbh200 (hcd);
+	return (fusbh200_read_frame_index(fusbh200) >> 3) % fusbh200->periodic_size;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * The EHCI in ChipIdea HDRC cannot be a separate module or device,
+ * because its registers (and irq) are shared between host/gadget/otg
+ * functions  and in order to facilitate role switching we cannot
+ * give the fusbh200 driver exclusive access to those.
+ */
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR (DRIVER_AUTHOR);
+MODULE_LICENSE ("GPL");
+
+static const struct hc_driver fusbh200_fusbh200_hc_driver = {
+	.description 		= hcd_name,
+	.product_desc 		= "Faraday USB2.0 Host Controller",
+	.hcd_priv_size 		= sizeof(struct fusbh200_hcd),
+
+	/*
+	 * generic hardware linkage
+	 */
+	.irq 			= fusbh200_irq,
+	.flags 			= HCD_MEMORY | HCD_USB2,
+
+	/*
+	 * basic lifecycle operations
+	 */
+	.reset 			= hcd_fusbh200_init,
+	.start 			= fusbh200_run,
+	.stop 			= fusbh200_stop,
+	.shutdown 		= fusbh200_shutdown,
+
+	/*
+	 * managing i/o requests and associated device resources
+	 */
+	.urb_enqueue 		= fusbh200_urb_enqueue,
+	.urb_dequeue 		= fusbh200_urb_dequeue,
+	.endpoint_disable 	= fusbh200_endpoint_disable,
+	.endpoint_reset 	= fusbh200_endpoint_reset,
+
+	/*
+	 * scheduling support
+	 */
+	.get_frame_number 	= fusbh200_get_frame,
+
+	/*
+	 * root hub support
+	 */
+	.hub_status_data 	= fusbh200_hub_status_data,
+	.hub_control 		= fusbh200_hub_control,
+	.bus_suspend 		= fusbh200_bus_suspend,
+	.bus_resume 		= fusbh200_bus_resume,
+
+	.relinquish_port 	= fusbh200_relinquish_port,
+	.port_handed_over 	= fusbh200_port_handed_over,
+
+	.clear_tt_buffer_complete = fusbh200_clear_tt_buffer_complete,
+};
+
+void fusbh200_init(struct fusbh200_hcd *fusbh200)
+{
+	u32 reg;
+
+	reg = fusbh200_readl(fusbh200, &fusbh200->regs->bmcsr);
+	reg |= BMCSR_INT_POLARITY;
+	reg &= ~BMCSR_VBUS_OFF;
+	fusbh200_writel(fusbh200, reg, &fusbh200->regs->bmcsr);
+
+	reg = fusbh200_readl(fusbh200, &fusbh200->regs->bmier);
+	fusbh200_writel(fusbh200, reg | BMIER_OVC_EN | BMIER_VBUS_ERR_EN,
+		&fusbh200->regs->bmier);
+}
+
+/**
+ * fusbh200_hcd_fusbh200_probe - initialize faraday FUSBH200 HCDs
+ *
+ * Allocates basic resources for this USB host controller, and
+ * then invokes the start() method for the HCD associated with it
+ * through the hotplug entry's driver_data.
+ */
+static int fusbh200_hcd_fusbh200_probe(struct platform_device *pdev)
+{
+	struct device			*dev = &pdev->dev;
+	struct usb_hcd 			*hcd;
+	struct resource			*res;
+	int 				irq;
+	int 				retval = -ENODEV;
+	struct fusbh200_hcd 		*fusbh200;
+
+	if (usb_disabled())
+		return -ENODEV;
+
+	pdev->dev.power.power_state = PMSG_ON;
+
+	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!res) {
+		dev_err(dev,
+			"Found HC with no IRQ. Check %s setup!\n",
+			dev_name(dev));
+		return -ENODEV;
+	}
+
+	irq = res->start;
+
+	hcd = usb_create_hcd(&fusbh200_fusbh200_hc_driver, dev,
+			dev_name(dev));
+	if (!hcd) {
+		dev_err(dev, "failed to create hcd with err %d\n", retval);
+		retval = -ENOMEM;
+		goto fail_create_hcd;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(dev,
+			"Found HC with no register addr. Check %s setup!\n",
+			dev_name(dev));
+		retval = -ENODEV;
+		goto fail_request_resource;
+	}
+
+	hcd->rsrc_start = res->start;
+	hcd->rsrc_len = resource_size(res);
+	hcd->has_tt = 1;
+
+	if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
+				fusbh200_fusbh200_hc_driver.description)) {
+		dev_dbg(dev, "controller already in use\n");
+		retval = -EBUSY;
+		goto fail_request_resource;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+	if (!res) {
+		dev_err(dev,
+			"Found HC with no register addr. Check %s setup!\n",
+			dev_name(dev));
+		retval = -ENODEV;
+		goto fail_request_resource;
+	}
+
+	hcd->regs = ioremap_nocache(res->start, resource_size(res));
+	if (hcd->regs == NULL) {
+		dev_dbg(dev, "error mapping memory\n");
+		retval = -EFAULT;
+		goto fail_ioremap;
+	}
+
+	fusbh200 = hcd_to_fusbh200(hcd);
+
+	fusbh200->caps = hcd->regs;
+
+	retval = fusbh200_setup(hcd);
+	if (retval)
+		return retval;
+
+	fusbh200_init(fusbh200);
+
+	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
+	if (retval) {
+		dev_err(dev, "failed to add hcd with err %d\n", retval);
+		goto fail_add_hcd;
+	}
+
+	return retval;
+
+fail_add_hcd:
+	iounmap(hcd->regs);
+fail_ioremap:
+	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
+fail_request_resource:
+	usb_put_hcd(hcd);
+fail_create_hcd:
+	dev_err(dev, "init %s fail, %d\n", dev_name(dev), retval);
+	return retval;
+}
+
+/**
+ * fusbh200_hcd_fusbh200_remove - shutdown processing for EHCI HCDs
+ * @dev: USB Host Controller being removed
+ *
+ * Reverses the effect of fotg2xx_usb_hcd_probe(), first invoking
+ * the HCD's stop() method.  It is always called from a thread
+ * context, normally "rmmod", "apmd", or something similar.
+ */
+int fusbh200_hcd_fusbh200_remove(struct platform_device *pdev)
+{
+	struct device *dev	= &pdev->dev;
+	struct usb_hcd *hcd	= dev_get_drvdata(dev);
+
+	if (!hcd)
+		return 0;
+
+	usb_remove_hcd(hcd);
+	iounmap(hcd->regs);
+	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
+	usb_put_hcd(hcd);
+	platform_set_drvdata(pdev, NULL);
+
+	return 0;
+}
+
+struct platform_driver fusbh200_hcd_fusbh200_driver = {
+	.driver = {
+		.name   = "fusbh200",
+	},
+	.probe  = fusbh200_hcd_fusbh200_probe,
+	.remove = fusbh200_hcd_fusbh200_remove,
+};
+
+static int __init fusbh200_hcd_init(void)
+{
+	int retval = 0;
+
+	if (usb_disabled())
+		return -ENODEV;
+
+	printk(KERN_INFO "%s: " DRIVER_DESC "\n", hcd_name);
+	set_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
+	if (test_bit(USB_UHCI_LOADED, &usb_hcds_loaded) ||
+			test_bit(USB_OHCI_LOADED, &usb_hcds_loaded))
+		printk(KERN_WARNING "Warning! fusbh200_hcd should always be loaded"
+				" before uhci_hcd and ohci_hcd, not after\n");
+
+	pr_debug("%s: block sizes: qh %Zd qtd %Zd itd %Zd\n",
+		 hcd_name,
+		 sizeof(struct fusbh200_qh), sizeof(struct fusbh200_qtd),
+		 sizeof(struct fusbh200_itd));
+
+#ifdef DEBUG
+	fusbh200_debug_root = debugfs_create_dir("fusbh200", usb_debug_root);
+	if (!fusbh200_debug_root) {
+		retval = -ENOENT;
+		goto err_debug;
+	}
+#endif
+
+	retval = platform_driver_register(&fusbh200_hcd_fusbh200_driver);
+	if (retval < 0)
+		goto clean;
+	return retval;
+
+	platform_driver_unregister(&fusbh200_hcd_fusbh200_driver);
+clean:
+#ifdef DEBUG
+	debugfs_remove(fusbh200_debug_root);
+	fusbh200_debug_root = NULL;
+err_debug:
+#endif
+	clear_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
+	return retval;
+}
+module_init(fusbh200_hcd_init);
+
+static void __exit fusbh200_hcd_cleanup(void)
+{
+	platform_driver_unregister(&fusbh200_hcd_fusbh200_driver);
+#ifdef DEBUG
+	debugfs_remove(fusbh200_debug_root);
+#endif
+	clear_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
+}
+module_exit(fusbh200_hcd_cleanup);

drivers/usb/host/fusbh200.h

@@ -0,0 +1,743 @@
+#ifndef __LINUX_FUSBH200_H
+#define __LINUX_FUSBH200_H
+
+/* definitions used for the EHCI driver */
+
+/*
+ * __hc32 and __hc16 are "Host Controller" types, they may be equivalent to
+ * __leXX (normally) or __beXX (given FUSBH200_BIG_ENDIAN_DESC), depending on
+ * the host controller implementation.
+ *
+ * To facilitate the strongest possible byte-order checking from "sparse"
+ * and so on, we use __leXX unless that's not practical.
+ */
+#define __hc32	__le32
+#define __hc16	__le16
+
+/* statistics can be kept for tuning/monitoring */
+struct fusbh200_stats {
+	/* irq usage */
+	unsigned long		normal;
+	unsigned long		error;
+	unsigned long		iaa;
+	unsigned long		lost_iaa;
+
+	/* termination of urbs from core */
+	unsigned long		complete;
+	unsigned long		unlink;
+};
+
+/* fusbh200_hcd->lock guards shared data against other CPUs:
+ *   fusbh200_hcd:	async, unlink, periodic (and shadow), ...
+ *   usb_host_endpoint: hcpriv
+ *   fusbh200_qh:	qh_next, qtd_list
+ *   fusbh200_qtd:	qtd_list
+ *
+ * Also, hold this lock when talking to HC registers or
+ * when updating hw_* fields in shared qh/qtd/... structures.
+ */
+
+#define	FUSBH200_MAX_ROOT_PORTS	1		/* see HCS_N_PORTS */
+
+/*
+ * fusbh200_rh_state values of FUSBH200_RH_RUNNING or above mean that the
+ * controller may be doing DMA.  Lower values mean there's no DMA.
+ */
+enum fusbh200_rh_state {
+	FUSBH200_RH_HALTED,
+	FUSBH200_RH_SUSPENDED,
+	FUSBH200_RH_RUNNING,
+	FUSBH200_RH_STOPPING
+};
+
+/*
+ * Timer events, ordered by increasing delay length.
+ * Always update event_delays_ns[] and event_handlers[] (defined in
+ * ehci-timer.c) in parallel with this list.
+ */
+enum fusbh200_hrtimer_event {
+	FUSBH200_HRTIMER_POLL_ASS,		/* Poll for async schedule off */
+	FUSBH200_HRTIMER_POLL_PSS,		/* Poll for periodic schedule off */
+	FUSBH200_HRTIMER_POLL_DEAD,		/* Wait for dead controller to stop */
+	FUSBH200_HRTIMER_UNLINK_INTR,	/* Wait for interrupt QH unlink */
+	FUSBH200_HRTIMER_FREE_ITDS,		/* Wait for unused iTDs and siTDs */
+	FUSBH200_HRTIMER_ASYNC_UNLINKS,	/* Unlink empty async QHs */
+	FUSBH200_HRTIMER_IAA_WATCHDOG,	/* Handle lost IAA interrupts */
+	FUSBH200_HRTIMER_DISABLE_PERIODIC,	/* Wait to disable periodic sched */
+	FUSBH200_HRTIMER_DISABLE_ASYNC,	/* Wait to disable async sched */
+	FUSBH200_HRTIMER_IO_WATCHDOG,	/* Check for missing IRQs */
+	FUSBH200_HRTIMER_NUM_EVENTS		/* Must come last */
+};
+#define FUSBH200_HRTIMER_NO_EVENT	99
+
+struct fusbh200_hcd {			/* one per controller */
+	/* timing support */
+	enum fusbh200_hrtimer_event	next_hrtimer_event;
+	unsigned		enabled_hrtimer_events;
+	ktime_t			hr_timeouts[FUSBH200_HRTIMER_NUM_EVENTS];
+	struct hrtimer		hrtimer;
+
+	int			PSS_poll_count;
+	int			ASS_poll_count;
+	int			died_poll_count;
+
+	/* glue to PCI and HCD framework */
+	struct fusbh200_caps __iomem *caps;
+	struct fusbh200_regs __iomem *regs;
+	struct fusbh200_dbg_port __iomem *debug;
+
+	__u32			hcs_params;	/* cached register copy */
+	spinlock_t		lock;
+	enum fusbh200_rh_state	rh_state;
+
+	/* general schedule support */
+	bool			scanning:1;
+	bool			need_rescan:1;
+	bool			intr_unlinking:1;
+	bool			async_unlinking:1;
+	bool			shutdown:1;
+	struct fusbh200_qh		*qh_scan_next;
+
+	/* async schedule support */
+	struct fusbh200_qh		*async;
+	struct fusbh200_qh		*dummy;		/* For AMD quirk use */
+	struct fusbh200_qh		*async_unlink;
+	struct fusbh200_qh		*async_unlink_last;
+	struct fusbh200_qh		*async_iaa;
+	unsigned		async_unlink_cycle;
+	unsigned		async_count;	/* async activity count */
+
+	/* periodic schedule support */
+#define	DEFAULT_I_TDPS		1024		/* some HCs can do less */
+	unsigned		periodic_size;
+	__hc32			*periodic;	/* hw periodic table */
+	dma_addr_t		periodic_dma;
+	struct list_head	intr_qh_list;
+	unsigned		i_thresh;	/* uframes HC might cache */
+
+	union fusbh200_shadow	*pshadow;	/* mirror hw periodic table */
+	struct fusbh200_qh		*intr_unlink;
+	struct fusbh200_qh		*intr_unlink_last;
+	unsigned		intr_unlink_cycle;
+	unsigned		now_frame;	/* frame from HC hardware */
+	unsigned		next_frame;	/* scan periodic, start here */
+	unsigned		intr_count;	/* intr activity count */
+	unsigned		isoc_count;	/* isoc activity count */
+	unsigned		periodic_count;	/* periodic activity count */
+	unsigned		uframe_periodic_max; /* max periodic time per uframe */
+
+
+	/* list of itds completed while now_frame was still active */
+	struct list_head	cached_itd_list;
+	struct fusbh200_itd	*last_itd_to_free;
+
+	/* per root hub port */
+	unsigned long		reset_done [FUSBH200_MAX_ROOT_PORTS];
+
+	/* bit vectors (one bit per port) */
+	unsigned long		bus_suspended;		/* which ports were
+			already suspended at the start of a bus suspend */
+	unsigned long		companion_ports;	/* which ports are
+			dedicated to the companion controller */
+	unsigned long		owned_ports;		/* which ports are
+			owned by the companion during a bus suspend */
+	unsigned long		port_c_suspend;		/* which ports have
+			the change-suspend feature turned on */
+	unsigned long		suspended_ports;	/* which ports are
+			suspended */
+	unsigned long		resuming_ports;		/* which ports have
+			started to resume */
+
+	/* per-HC memory pools (could be per-bus, but ...) */
+	struct dma_pool		*qh_pool;	/* qh per active urb */
+	struct dma_pool		*qtd_pool;	/* one or more per qh */
+	struct dma_pool		*itd_pool;	/* itd per iso urb */
+
+	unsigned		random_frame;
+	unsigned long		next_statechange;
+	ktime_t			last_periodic_enable;
+	u32			command;
+
+	/* SILICON QUIRKS */
+	unsigned		need_io_watchdog:1;
+	unsigned		fs_i_thresh:1;	/* Intel iso scheduling */
+
+	u8			sbrn;		/* packed release number */
+
+	/* irq statistics */
+#ifdef FUSBH200_STATS
+	struct fusbh200_stats	stats;
+#	define COUNT(x) do { (x)++; } while (0)
+#else
+#	define COUNT(x) do {} while (0)
+#endif
+
+	/* debug files */
+#ifdef DEBUG
+	struct dentry		*debug_dir;
+#endif
+};
+
+/* convert between an HCD pointer and the corresponding FUSBH200_HCD */
+static inline struct fusbh200_hcd *hcd_to_fusbh200 (struct usb_hcd *hcd)
+{
+	return (struct fusbh200_hcd *) (hcd->hcd_priv);
+}
+static inline struct usb_hcd *fusbh200_to_hcd (struct fusbh200_hcd *fusbh200)
+{
+	return container_of ((void *) fusbh200, struct usb_hcd, hcd_priv);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* EHCI register interface, corresponds to EHCI Revision 0.95 specification */
+
+/* Section 2.2 Host Controller Capability Registers */
+struct fusbh200_caps {
+	/* these fields are specified as 8 and 16 bit registers,
+	 * but some hosts can't perform 8 or 16 bit PCI accesses.
+	 * some hosts treat caplength and hciversion as parts of a 32-bit
+	 * register, others treat them as two separate registers, this
+	 * affects the memory map for big endian controllers.
+	 */
+	u32		hc_capbase;
+#define HC_LENGTH(fusbh200, p)	(0x00ff&((p) >> /* bits 7:0 / offset 00h */ \
+				(fusbh200_big_endian_capbase(fusbh200) ? 24 : 0)))
+#define HC_VERSION(fusbh200, p)	(0xffff&((p) >> /* bits 31:16 / offset 02h */ \
+				(fusbh200_big_endian_capbase(fusbh200) ? 0 : 16)))
+	u32		hcs_params;     /* HCSPARAMS - offset 0x4 */
+#define HCS_N_PORTS(p)		(((p)>>0)&0xf)	/* bits 3:0, ports on HC */
+
+	u32		hcc_params;      /* HCCPARAMS - offset 0x8 */
+#define HCC_CANPARK(p)		((p)&(1 << 2))  /* true: can park on async qh */
+#define HCC_PGM_FRAMELISTLEN(p) ((p)&(1 << 1))  /* true: periodic_size changes*/
+	u8		portroute[8];	 /* nibbles for routing - offset 0xC */
+};
+
+
+/* Section 2.3 Host Controller Operational Registers */
+struct fusbh200_regs {
+
+	/* USBCMD: offset 0x00 */
+	u32		command;
+
+/* EHCI 1.1 addendum */
+/* 23:16 is r/w intr rate, in microframes; default "8" == 1/msec */
+#define CMD_PARK	(1<<11)		/* enable "park" on async qh */
+#define CMD_PARK_CNT(c)	(((c)>>8)&3)	/* how many transfers to park for */
+#define CMD_IAAD	(1<<6)		/* "doorbell" interrupt async advance */
+#define CMD_ASE		(1<<5)		/* async schedule enable */
+#define CMD_PSE		(1<<4)		/* periodic schedule enable */
+/* 3:2 is periodic frame list size */
+#define CMD_RESET	(1<<1)		/* reset HC not bus */
+#define CMD_RUN		(1<<0)		/* start/stop HC */
+
+	/* USBSTS: offset 0x04 */
+	u32		status;
+#define STS_ASS		(1<<15)		/* Async Schedule Status */
+#define STS_PSS		(1<<14)		/* Periodic Schedule Status */
+#define STS_RECL	(1<<13)		/* Reclamation */
+#define STS_HALT	(1<<12)		/* Not running (any reason) */
+/* some bits reserved */
+	/* these STS_* flags are also intr_enable bits (USBINTR) */
+#define STS_IAA		(1<<5)		/* Interrupted on async advance */
+#define STS_FATAL	(1<<4)		/* such as some PCI access errors */
+#define STS_FLR		(1<<3)		/* frame list rolled over */
+#define STS_PCD		(1<<2)		/* port change detect */
+#define STS_ERR		(1<<1)		/* "error" completion (overflow, ...) */
+#define STS_INT		(1<<0)		/* "normal" completion (short, ...) */
+
+	/* USBINTR: offset 0x08 */
+	u32		intr_enable;
+
+	/* FRINDEX: offset 0x0C */
+	u32		frame_index;	/* current microframe number */
+	/* CTRLDSSEGMENT: offset 0x10 */
+	u32		segment;	/* address bits 63:32 if needed */
+	/* PERIODICLISTBASE: offset 0x14 */
+	u32		frame_list;	/* points to periodic list */
+	/* ASYNCLISTADDR: offset 0x18 */
+	u32		async_next;	/* address of next async queue head */
+
+	u32	reserved1;
+	/* PORTSC: offset 0x20 */
+	u32	port_status;
+/* 31:23 reserved */
+#define PORT_USB11(x) (((x)&(3<<10)) == (1<<10))	/* USB 1.1 device */
+#define PORT_RESET	(1<<8)		/* reset port */
+#define PORT_SUSPEND	(1<<7)		/* suspend port */
+#define PORT_RESUME	(1<<6)		/* resume it */
+#define PORT_PEC	(1<<3)		/* port enable change */
+#define PORT_PE		(1<<2)		/* port enable */
+#define PORT_CSC	(1<<1)		/* connect status change */
+#define PORT_CONNECT	(1<<0)		/* device connected */
+#define PORT_RWC_BITS   (PORT_CSC | PORT_PEC)
+
+	u32	reserved2[3];
+
+	/* BMCSR: offset 0x30 */
+	u32	bmcsr; /* Bus Moniter Control/Status Register */
+#define BMCSR_HOST_SPD_TYP	(3<<9)
+#define BMCSR_VBUS_OFF		(1<<4)
+#define BMCSR_INT_POLARITY	(1<<3)
+
+	/* BMISR: offset 0x34 */
+	u32	bmisr; /* Bus Moniter Interrupt Status Register*/
+#define BMISR_OVC		(1<<1)
+
+	/* BMIER: offset 0x38 */
+	u32	bmier; /* Bus Moniter Interrupt Enable Register */
+#define BMIER_OVC_EN		(1<<1)
+#define BMIER_VBUS_ERR_EN	(1<<0)
+};
+
+/* Appendix C, Debug port ... intended for use with special "debug devices"
+ * that can help if there's no serial console.  (nonstandard enumeration.)
+ */
+struct fusbh200_dbg_port {
+	u32	control;
+#define DBGP_OWNER	(1<<30)
+#define DBGP_ENABLED	(1<<28)
+#define DBGP_DONE	(1<<16)
+#define DBGP_INUSE	(1<<10)
+#define DBGP_ERRCODE(x)	(((x)>>7)&0x07)
+#	define DBGP_ERR_BAD	1
+#	define DBGP_ERR_SIGNAL	2
+#define DBGP_ERROR	(1<<6)
+#define DBGP_GO		(1<<5)
+#define DBGP_OUT	(1<<4)
+#define DBGP_LEN(x)	(((x)>>0)&0x0f)
+	u32	pids;
+#define DBGP_PID_GET(x)		(((x)>>16)&0xff)
+#define DBGP_PID_SET(data, tok)	(((data)<<8)|(tok))
+	u32	data03;
+	u32	data47;
+	u32	address;
+#define DBGP_EPADDR(dev, ep)	(((dev)<<8)|(ep))
+};
+
+#ifdef CONFIG_EARLY_PRINTK_DBGP
+#include <linux/init.h>
+extern int __init early_dbgp_init(char *s);
+extern struct console early_dbgp_console;
+#endif /* CONFIG_EARLY_PRINTK_DBGP */
+
+struct usb_hcd;
+
+static inline int xen_dbgp_reset_prep(struct usb_hcd *hcd)
+{
+	return 1; /* Shouldn't this be 0? */
+}
+
+static inline int xen_dbgp_external_startup(struct usb_hcd *hcd)
+{
+	return -1;
+}
+
+#ifdef CONFIG_EARLY_PRINTK_DBGP
+/* Call backs from fusbh200 host driver to fusbh200 debug driver */
+extern int dbgp_external_startup(struct usb_hcd *);
+extern int dbgp_reset_prep(struct usb_hcd *hcd);
+#else
+static inline int dbgp_reset_prep(struct usb_hcd *hcd)
+{
+	return xen_dbgp_reset_prep(hcd);
+}
+static inline int dbgp_external_startup(struct usb_hcd *hcd)
+{
+	return xen_dbgp_external_startup(hcd);
+}
+#endif
+
+/*-------------------------------------------------------------------------*/
+
+#define	QTD_NEXT(fusbh200, dma)	cpu_to_hc32(fusbh200, (u32)dma)
+
+/*
+ * EHCI Specification 0.95 Section 3.5
+ * QTD: describe data transfer components (buffer, direction, ...)
+ * See Fig 3-6 "Queue Element Transfer Descriptor Block Diagram".
+ *
+ * These are associated only with "QH" (Queue Head) structures,
+ * used with control, bulk, and interrupt transfers.
+ */
+struct fusbh200_qtd {
+	/* first part defined by EHCI spec */
+	__hc32			hw_next;	/* see EHCI 3.5.1 */
+	__hc32			hw_alt_next;    /* see EHCI 3.5.2 */
+	__hc32			hw_token;       /* see EHCI 3.5.3 */
+#define	QTD_TOGGLE	(1 << 31)	/* data toggle */
+#define	QTD_LENGTH(tok)	(((tok)>>16) & 0x7fff)
+#define	QTD_IOC		(1 << 15)	/* interrupt on complete */
+#define	QTD_CERR(tok)	(((tok)>>10) & 0x3)
+#define	QTD_PID(tok)	(((tok)>>8) & 0x3)
+#define	QTD_STS_ACTIVE	(1 << 7)	/* HC may execute this */
+#define	QTD_STS_HALT	(1 << 6)	/* halted on error */
+#define	QTD_STS_DBE	(1 << 5)	/* data buffer error (in HC) */
+#define	QTD_STS_BABBLE	(1 << 4)	/* device was babbling (qtd halted) */
+#define	QTD_STS_XACT	(1 << 3)	/* device gave illegal response */
+#define	QTD_STS_MMF	(1 << 2)	/* incomplete split transaction */
+#define	QTD_STS_STS	(1 << 1)	/* split transaction state */
+#define	QTD_STS_PING	(1 << 0)	/* issue PING? */
+
+#define ACTIVE_BIT(fusbh200)	cpu_to_hc32(fusbh200, QTD_STS_ACTIVE)
+#define HALT_BIT(fusbh200)		cpu_to_hc32(fusbh200, QTD_STS_HALT)
+#define STATUS_BIT(fusbh200)	cpu_to_hc32(fusbh200, QTD_STS_STS)
+
+	__hc32			hw_buf [5];        /* see EHCI 3.5.4 */
+	__hc32			hw_buf_hi [5];        /* Appendix B */
+
+	/* the rest is HCD-private */
+	dma_addr_t		qtd_dma;		/* qtd address */
+	struct list_head	qtd_list;		/* sw qtd list */
+	struct urb		*urb;			/* qtd's urb */
+	size_t			length;			/* length of buffer */
+} __attribute__ ((aligned (32)));
+
+/* mask NakCnt+T in qh->hw_alt_next */
+#define QTD_MASK(fusbh200)	cpu_to_hc32 (fusbh200, ~0x1f)
+
+#define IS_SHORT_READ(token) (QTD_LENGTH (token) != 0 && QTD_PID (token) == 1)
+
+/*-------------------------------------------------------------------------*/
+
+/* type tag from {qh,itd,fstn}->hw_next */
+#define Q_NEXT_TYPE(fusbh200,dma)	((dma) & cpu_to_hc32(fusbh200, 3 << 1))
+
+/*
+ * Now the following defines are not converted using the
+ * cpu_to_le32() macro anymore, since we have to support
+ * "dynamic" switching between be and le support, so that the driver
+ * can be used on one system with SoC EHCI controller using big-endian
+ * descriptors as well as a normal little-endian PCI EHCI controller.
+ */
+/* values for that type tag */
+#define Q_TYPE_ITD	(0 << 1)
+#define Q_TYPE_QH	(1 << 1)
+#define Q_TYPE_SITD	(2 << 1)
+#define Q_TYPE_FSTN	(3 << 1)
+
+/* next async queue entry, or pointer to interrupt/periodic QH */
+#define QH_NEXT(fusbh200,dma)	(cpu_to_hc32(fusbh200, (((u32)dma)&~0x01f)|Q_TYPE_QH))
+
+/* for periodic/async schedules and qtd lists, mark end of list */
+#define FUSBH200_LIST_END(fusbh200)	cpu_to_hc32(fusbh200, 1) /* "null pointer" to hw */
+
+/*
+ * Entries in periodic shadow table are pointers to one of four kinds
+ * of data structure.  That's dictated by the hardware; a type tag is
+ * encoded in the low bits of the hardware's periodic schedule.  Use
+ * Q_NEXT_TYPE to get the tag.
+ *
+ * For entries in the async schedule, the type tag always says "qh".
+ */
+union fusbh200_shadow {
+	struct fusbh200_qh	*qh;		/* Q_TYPE_QH */
+	struct fusbh200_itd	*itd;		/* Q_TYPE_ITD */
+	struct fusbh200_fstn	*fstn;		/* Q_TYPE_FSTN */
+	__hc32			*hw_next;	/* (all types) */
+	void			*ptr;
+};
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * EHCI Specification 0.95 Section 3.6
+ * QH: describes control/bulk/interrupt endpoints
+ * See Fig 3-7 "Queue Head Structure Layout".
+ *
+ * These appear in both the async and (for interrupt) periodic schedules.
+ */
+
+/* first part defined by EHCI spec */
+struct fusbh200_qh_hw {
+	__hc32			hw_next;	/* see EHCI 3.6.1 */
+	__hc32			hw_info1;       /* see EHCI 3.6.2 */
+#define	QH_CONTROL_EP	(1 << 27)	/* FS/LS control endpoint */
+#define	QH_HEAD		(1 << 15)	/* Head of async reclamation list */
+#define	QH_TOGGLE_CTL	(1 << 14)	/* Data toggle control */
+#define	QH_HIGH_SPEED	(2 << 12)	/* Endpoint speed */
+#define	QH_LOW_SPEED	(1 << 12)
+#define	QH_FULL_SPEED	(0 << 12)
+#define	QH_INACTIVATE	(1 << 7)	/* Inactivate on next transaction */
+	__hc32			hw_info2;        /* see EHCI 3.6.2 */
+#define	QH_SMASK	0x000000ff
+#define	QH_CMASK	0x0000ff00
+#define	QH_HUBADDR	0x007f0000
+#define	QH_HUBPORT	0x3f800000
+#define	QH_MULT		0xc0000000
+	__hc32			hw_current;	/* qtd list - see EHCI 3.6.4 */
+
+	/* qtd overlay (hardware parts of a struct fusbh200_qtd) */
+	__hc32			hw_qtd_next;
+	__hc32			hw_alt_next;
+	__hc32			hw_token;
+	__hc32			hw_buf [5];
+	__hc32			hw_buf_hi [5];
+} __attribute__ ((aligned(32)));
+
+struct fusbh200_qh {
+	struct fusbh200_qh_hw	*hw;		/* Must come first */
+	/* the rest is HCD-private */
+	dma_addr_t		qh_dma;		/* address of qh */
+	union fusbh200_shadow	qh_next;	/* ptr to qh; or periodic */
+	struct list_head	qtd_list;	/* sw qtd list */
+	struct list_head	intr_node;	/* list of intr QHs */
+	struct fusbh200_qtd		*dummy;
+	struct fusbh200_qh		*unlink_next;	/* next on unlink list */
+
+	unsigned		unlink_cycle;
+
+	u8			needs_rescan;	/* Dequeue during giveback */
+	u8			qh_state;
+#define	QH_STATE_LINKED		1		/* HC sees this */
+#define	QH_STATE_UNLINK		2		/* HC may still see this */
+#define	QH_STATE_IDLE		3		/* HC doesn't see this */
+#define	QH_STATE_UNLINK_WAIT	4		/* LINKED and on unlink q */
+#define	QH_STATE_COMPLETING	5		/* don't touch token.HALT */
+
+	u8			xacterrs;	/* XactErr retry counter */
+#define	QH_XACTERR_MAX		32		/* XactErr retry limit */
+
+	/* periodic schedule info */
+	u8			usecs;		/* intr bandwidth */
+	u8			gap_uf;		/* uframes split/csplit gap */
+	u8			c_usecs;	/* ... split completion bw */
+	u16			tt_usecs;	/* tt downstream bandwidth */
+	unsigned short		period;		/* polling interval */
+	unsigned short		start;		/* where polling starts */
+#define NO_FRAME ((unsigned short)~0)			/* pick new start */
+
+	struct usb_device	*dev;		/* access to TT */
+	unsigned		is_out:1;	/* bulk or intr OUT */
+	unsigned		clearing_tt:1;	/* Clear-TT-Buf in progress */
+};
+
+/*-------------------------------------------------------------------------*/
+
+/* description of one iso transaction (up to 3 KB data if highspeed) */
+struct fusbh200_iso_packet {
+	/* These will be copied to iTD when scheduling */
+	u64			bufp;		/* itd->hw_bufp{,_hi}[pg] |= */
+	__hc32			transaction;	/* itd->hw_transaction[i] |= */
+	u8			cross;		/* buf crosses pages */
+	/* for full speed OUT splits */
+	u32			buf1;
+};
+
+/* temporary schedule data for packets from iso urbs (both speeds)
+ * each packet is one logical usb transaction to the device (not TT),
+ * beginning at stream->next_uframe
+ */
+struct fusbh200_iso_sched {
+	struct list_head	td_list;
+	unsigned		span;
+	struct fusbh200_iso_packet	packet [0];
+};
+
+/*
+ * fusbh200_iso_stream - groups all (s)itds for this endpoint.
+ * acts like a qh would, if EHCI had them for ISO.
+ */
+struct fusbh200_iso_stream {
+	/* first field matches fusbh200_hq, but is NULL */
+	struct fusbh200_qh_hw	*hw;
+
+	u8			bEndpointAddress;
+	u8			highspeed;
+	struct list_head	td_list;	/* queued itds */
+	struct list_head	free_list;	/* list of unused itds */
+	struct usb_device	*udev;
+	struct usb_host_endpoint *ep;
+
+	/* output of (re)scheduling */
+	int			next_uframe;
+	__hc32			splits;
+
+	/* the rest is derived from the endpoint descriptor,
+	 * trusting urb->interval == f(epdesc->bInterval) and
+	 * including the extra info for hw_bufp[0..2]
+	 */
+	u8			usecs, c_usecs;
+	u16			interval;
+	u16			tt_usecs;
+	u16			maxp;
+	u16			raw_mask;
+	unsigned		bandwidth;
+
+	/* This is used to initialize iTD's hw_bufp fields */
+	__hc32			buf0;
+	__hc32			buf1;
+	__hc32			buf2;
+
+	/* this is used to initialize sITD's tt info */
+	__hc32			address;
+};
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * EHCI Specification 0.95 Section 3.3
+ * Fig 3-4 "Isochronous Transaction Descriptor (iTD)"
+ *
+ * Schedule records for high speed iso xfers
+ */
+struct fusbh200_itd {
+	/* first part defined by EHCI spec */
+	__hc32			hw_next;           /* see EHCI 3.3.1 */
+	__hc32			hw_transaction [8]; /* see EHCI 3.3.2 */
+#define FUSBH200_ISOC_ACTIVE        (1<<31)        /* activate transfer this slot */
+#define FUSBH200_ISOC_BUF_ERR       (1<<30)        /* Data buffer error */
+#define FUSBH200_ISOC_BABBLE        (1<<29)        /* babble detected */
+#define FUSBH200_ISOC_XACTERR       (1<<28)        /* XactErr - transaction error */
+#define	FUSBH200_ITD_LENGTH(tok)	(((tok)>>16) & 0x0fff)
+#define	FUSBH200_ITD_IOC		(1 << 15)	/* interrupt on complete */
+
+#define ITD_ACTIVE(fusbh200)	cpu_to_hc32(fusbh200, FUSBH200_ISOC_ACTIVE)
+
+	__hc32			hw_bufp [7];	/* see EHCI 3.3.3 */
+	__hc32			hw_bufp_hi [7];	/* Appendix B */
+
+	/* the rest is HCD-private */
+	dma_addr_t		itd_dma;	/* for this itd */
+	union fusbh200_shadow	itd_next;	/* ptr to periodic q entry */
+
+	struct urb		*urb;
+	struct fusbh200_iso_stream	*stream;	/* endpoint's queue */
+	struct list_head	itd_list;	/* list of stream's itds */
+
+	/* any/all hw_transactions here may be used by that urb */
+	unsigned		frame;		/* where scheduled */
+	unsigned		pg;
+	unsigned		index[8];	/* in urb->iso_frame_desc */
+} __attribute__ ((aligned (32)));
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * EHCI Specification 0.96 Section 3.7
+ * Periodic Frame Span Traversal Node (FSTN)
+ *
+ * Manages split interrupt transactions (using TT) that span frame boundaries
+ * into uframes 0/1; see 4.12.2.2.  In those uframes, a "save place" FSTN
+ * makes the HC jump (back) to a QH to scan for fs/ls QH completions until
+ * it hits a "restore" FSTN; then it returns to finish other uframe 0/1 work.
+ */
+struct fusbh200_fstn {
+	__hc32			hw_next;	/* any periodic q entry */
+	__hc32			hw_prev;	/* qh or FUSBH200_LIST_END */
+
+	/* the rest is HCD-private */
+	dma_addr_t		fstn_dma;
+	union fusbh200_shadow	fstn_next;	/* ptr to periodic q entry */
+} __attribute__ ((aligned (32)));
+
+/*-------------------------------------------------------------------------*/
+
+/* Prepare the PORTSC wakeup flags during controller suspend/resume */
+
+#define fusbh200_prepare_ports_for_controller_suspend(fusbh200, do_wakeup)	\
+		fusbh200_adjust_port_wakeup_flags(fusbh200, true, do_wakeup);
+
+#define fusbh200_prepare_ports_for_controller_resume(fusbh200)			\
+		fusbh200_adjust_port_wakeup_flags(fusbh200, false, false);
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Some EHCI controllers have a Transaction Translator built into the
+ * root hub. This is a non-standard feature.  Each controller will need
+ * to add code to the following inline functions, and call them as
+ * needed (mostly in root hub code).
+ */
+
+static inline unsigned int
+fusbh200_get_speed(struct fusbh200_hcd *fusbh200, unsigned int portsc)
+{
+	return (readl(&fusbh200->regs->bmcsr)
+		& BMCSR_HOST_SPD_TYP) >> 9;
+}
+
+/* Returns the speed of a device attached to a port on the root hub. */
+static inline unsigned int
+fusbh200_port_speed(struct fusbh200_hcd *fusbh200, unsigned int portsc)
+{
+	switch (fusbh200_get_speed(fusbh200, portsc)) {
+	case 0:
+		return 0;
+	case 1:
+		return USB_PORT_STAT_LOW_SPEED;
+	case 2:
+	default:
+		return USB_PORT_STAT_HIGH_SPEED;
+	}
+}
+
+/*-------------------------------------------------------------------------*/
+
+#define	fusbh200_has_fsl_portno_bug(e)		(0)
+
+/*
+ * While most USB host controllers implement their registers in
+ * little-endian format, a minority (celleb companion chip) implement
+ * them in big endian format.
+ *
+ * This attempts to support either format at compile time without a
+ * runtime penalty, or both formats with the additional overhead
+ * of checking a flag bit.
+ *
+ */
+
+#define fusbh200_big_endian_mmio(e)	0
+#define fusbh200_big_endian_capbase(e)	0
+
+static inline unsigned int fusbh200_readl(const struct fusbh200_hcd *fusbh200,
+		__u32 __iomem * regs)
+{
+	return readl(regs);
+}
+
+static inline void fusbh200_writel(const struct fusbh200_hcd *fusbh200,
+		const unsigned int val, __u32 __iomem *regs)
+{
+	writel(val, regs);
+}
+
+/* cpu to fusbh200 */
+static inline __hc32 cpu_to_hc32 (const struct fusbh200_hcd *fusbh200, const u32 x)
+{
+	return cpu_to_le32(x);
+}
+
+/* fusbh200 to cpu */
+static inline u32 hc32_to_cpu (const struct fusbh200_hcd *fusbh200, const __hc32 x)
+{
+	return le32_to_cpu(x);
+}
+
+static inline u32 hc32_to_cpup (const struct fusbh200_hcd *fusbh200, const __hc32 *x)
+{
+	return le32_to_cpup(x);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static inline unsigned fusbh200_read_frame_index(struct fusbh200_hcd *fusbh200)
+{
+	return fusbh200_readl(fusbh200, &fusbh200->regs->frame_index);
+}
+
+#define fusbh200_itdlen(urb, desc, t) ({			\
+	usb_pipein((urb)->pipe) ?				\
+	(desc)->length - FUSBH200_ITD_LENGTH(t) :			\
+	FUSBH200_ITD_LENGTH(t);					\
+})
+/*-------------------------------------------------------------------------*/
+
+#ifndef DEBUG
+#define STUB_DEBUG_FILES
+#endif	/* DEBUG */
+
+/*-------------------------------------------------------------------------*/
+
+#endif /* __LINUX_FUSBH200_H */