spi: remove completely broken Tegra driver

The current SPI driver has many issues. Examples are:

* Segfaulting on most transfers due to expecting all transfers to have
  both RX and TX buffers.
* Hanging on TX transfers since the whole driver flow is driven by RX
  DMA completion, but the HW is only told to enable RX for RX transfers.
* Use of clk_disable_unprepare() from atomic context.
* Once those and other minor issues are fixed, the driver still doesn't
  actually work.
* The driver also implements a deprecated API to the SPI core.

For this reason, simply remove the driver completely. This has two
advantages:

1) This will remove the last use of Tegra's <mach/dma.h>, which will
   allow that file to be removed, which is required for single zImage
   work.

2) The downstream driver is significaly different from the current
   code. I believe a patch to re-add the downstream driver (with
   appropriate cleanup) will be much simpler to review if it's a new
   file rather than randomly interspered with essentially unrelated
   existing code.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/spi/Kconfig

@@ -377,12 +377,6 @@ config SPI_MXS
 	help
 	  SPI driver for Freescale MXS devices.
 
-config SPI_TEGRA
-	tristate "Nvidia Tegra SPI controller"
-	depends on ARCH_TEGRA && (TEGRA_SYSTEM_DMA || TEGRA20_APB_DMA)
-	help
-	  SPI driver for NVidia Tegra SoCs
-
 config SPI_TI_SSP
 	tristate "TI Sequencer Serial Port - SPI Support"
 	depends on MFD_TI_SSP

drivers/spi/Makefile

@@ -59,7 +59,6 @@ obj-$(CONFIG_SPI_SH_MSIOF)		+= spi-sh-msiof.o
 obj-$(CONFIG_SPI_SH_SCI)		+= spi-sh-sci.o
 obj-$(CONFIG_SPI_SIRF)		+= spi-sirf.o
 obj-$(CONFIG_SPI_STMP3XXX)		+= spi-stmp.o
-obj-$(CONFIG_SPI_TEGRA)			+= spi-tegra.o
 obj-$(CONFIG_SPI_TI_SSP)		+= spi-ti-ssp.o
 obj-$(CONFIG_SPI_TLE62X0)		+= spi-tle62x0.o
 obj-$(CONFIG_SPI_TOPCLIFF_PCH)		+= spi-topcliff-pch.o

drivers/spi/spi-tegra.c

@@ -1,702 +0,0 @@
-/*
- * Driver for Nvidia TEGRA spi controller.
- *
- * Copyright (C) 2010 Google, Inc.
- *
- * Author:
- *     Erik Gilling <konkers@android.com>
- *
- * This software is licensed under the terms of the GNU General Public
- * License version 2, as published by the Free Software Foundation, and
- * may be copied, distributed, and modified under those terms.
- *
- * 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.
- *
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/err.h>
-#include <linux/platform_device.h>
-#include <linux/io.h>
-#include <linux/dma-mapping.h>
-#include <linux/dmapool.h>
-#include <linux/clk.h>
-#include <linux/interrupt.h>
-#include <linux/delay.h>
-
-#include <linux/spi/spi.h>
-#include <linux/dmaengine.h>
-
-#include <mach/dma.h>
-
-#define SLINK_COMMAND		0x000
-#define   SLINK_BIT_LENGTH(x)		(((x) & 0x1f) << 0)
-#define   SLINK_WORD_SIZE(x)		(((x) & 0x1f) << 5)
-#define   SLINK_BOTH_EN			(1 << 10)
-#define   SLINK_CS_SW			(1 << 11)
-#define   SLINK_CS_VALUE		(1 << 12)
-#define   SLINK_CS_POLARITY		(1 << 13)
-#define   SLINK_IDLE_SDA_DRIVE_LOW	(0 << 16)
-#define   SLINK_IDLE_SDA_DRIVE_HIGH	(1 << 16)
-#define   SLINK_IDLE_SDA_PULL_LOW	(2 << 16)
-#define   SLINK_IDLE_SDA_PULL_HIGH	(3 << 16)
-#define   SLINK_IDLE_SDA_MASK		(3 << 16)
-#define   SLINK_CS_POLARITY1		(1 << 20)
-#define   SLINK_CK_SDA			(1 << 21)
-#define   SLINK_CS_POLARITY2		(1 << 22)
-#define   SLINK_CS_POLARITY3		(1 << 23)
-#define   SLINK_IDLE_SCLK_DRIVE_LOW	(0 << 24)
-#define   SLINK_IDLE_SCLK_DRIVE_HIGH	(1 << 24)
-#define   SLINK_IDLE_SCLK_PULL_LOW	(2 << 24)
-#define   SLINK_IDLE_SCLK_PULL_HIGH	(3 << 24)
-#define   SLINK_IDLE_SCLK_MASK		(3 << 24)
-#define   SLINK_M_S			(1 << 28)
-#define   SLINK_WAIT			(1 << 29)
-#define   SLINK_GO			(1 << 30)
-#define   SLINK_ENB			(1 << 31)
-
-#define SLINK_COMMAND2		0x004
-#define   SLINK_LSBFE			(1 << 0)
-#define   SLINK_SSOE			(1 << 1)
-#define   SLINK_SPIE			(1 << 4)
-#define   SLINK_BIDIROE			(1 << 6)
-#define   SLINK_MODFEN			(1 << 7)
-#define   SLINK_INT_SIZE(x)		(((x) & 0x1f) << 8)
-#define   SLINK_CS_ACTIVE_BETWEEN	(1 << 17)
-#define   SLINK_SS_EN_CS(x)		(((x) & 0x3) << 18)
-#define   SLINK_SS_SETUP(x)		(((x) & 0x3) << 20)
-#define   SLINK_FIFO_REFILLS_0		(0 << 22)
-#define   SLINK_FIFO_REFILLS_1		(1 << 22)
-#define   SLINK_FIFO_REFILLS_2		(2 << 22)
-#define   SLINK_FIFO_REFILLS_3		(3 << 22)
-#define   SLINK_FIFO_REFILLS_MASK	(3 << 22)
-#define   SLINK_WAIT_PACK_INT(x)	(((x) & 0x7) << 26)
-#define   SLINK_SPC0			(1 << 29)
-#define   SLINK_TXEN			(1 << 30)
-#define   SLINK_RXEN			(1 << 31)
-
-#define SLINK_STATUS		0x008
-#define   SLINK_COUNT(val)		(((val) >> 0) & 0x1f)
-#define   SLINK_WORD(val)		(((val) >> 5) & 0x1f)
-#define   SLINK_BLK_CNT(val)		(((val) >> 0) & 0xffff)
-#define   SLINK_MODF			(1 << 16)
-#define   SLINK_RX_UNF			(1 << 18)
-#define   SLINK_TX_OVF			(1 << 19)
-#define   SLINK_TX_FULL			(1 << 20)
-#define   SLINK_TX_EMPTY		(1 << 21)
-#define   SLINK_RX_FULL			(1 << 22)
-#define   SLINK_RX_EMPTY		(1 << 23)
-#define   SLINK_TX_UNF			(1 << 24)
-#define   SLINK_RX_OVF			(1 << 25)
-#define   SLINK_TX_FLUSH		(1 << 26)
-#define   SLINK_RX_FLUSH		(1 << 27)
-#define   SLINK_SCLK			(1 << 28)
-#define   SLINK_ERR			(1 << 29)
-#define   SLINK_RDY			(1 << 30)
-#define   SLINK_BSY			(1 << 31)
-
-#define SLINK_MAS_DATA		0x010
-#define SLINK_SLAVE_DATA	0x014
-
-#define SLINK_DMA_CTL		0x018
-#define   SLINK_DMA_BLOCK_SIZE(x)	(((x) & 0xffff) << 0)
-#define   SLINK_TX_TRIG_1		(0 << 16)
-#define   SLINK_TX_TRIG_4		(1 << 16)
-#define   SLINK_TX_TRIG_8		(2 << 16)
-#define   SLINK_TX_TRIG_16		(3 << 16)
-#define   SLINK_TX_TRIG_MASK		(3 << 16)
-#define   SLINK_RX_TRIG_1		(0 << 18)
-#define   SLINK_RX_TRIG_4		(1 << 18)
-#define   SLINK_RX_TRIG_8		(2 << 18)
-#define   SLINK_RX_TRIG_16		(3 << 18)
-#define   SLINK_RX_TRIG_MASK		(3 << 18)
-#define   SLINK_PACKED			(1 << 20)
-#define   SLINK_PACK_SIZE_4		(0 << 21)
-#define   SLINK_PACK_SIZE_8		(1 << 21)
-#define   SLINK_PACK_SIZE_16		(2 << 21)
-#define   SLINK_PACK_SIZE_32		(3 << 21)
-#define   SLINK_PACK_SIZE_MASK		(3 << 21)
-#define   SLINK_IE_TXC			(1 << 26)
-#define   SLINK_IE_RXC			(1 << 27)
-#define   SLINK_DMA_EN			(1 << 31)
-
-#define SLINK_STATUS2		0x01c
-#define   SLINK_TX_FIFO_EMPTY_COUNT(val)	(((val) & 0x3f) >> 0)
-#define   SLINK_RX_FIFO_FULL_COUNT(val)		(((val) & 0x3f) >> 16)
-
-#define SLINK_TX_FIFO		0x100
-#define SLINK_RX_FIFO		0x180
-
-static const unsigned long spi_tegra_req_sels[] = {
-	TEGRA_DMA_REQ_SEL_SL2B1,
-	TEGRA_DMA_REQ_SEL_SL2B2,
-	TEGRA_DMA_REQ_SEL_SL2B3,
-	TEGRA_DMA_REQ_SEL_SL2B4,
-};
-
-#define BB_LEN			32
-
-struct spi_tegra_data {
-	struct spi_master	*master;
-	struct platform_device	*pdev;
-	spinlock_t		lock;
-
-	struct clk		*clk;
-	void __iomem		*base;
-	unsigned long		phys;
-
-	u32			cur_speed;
-
-	struct list_head	queue;
-	struct spi_transfer	*cur;
-	unsigned		cur_pos;
-	unsigned		cur_len;
-	unsigned		cur_bytes_per_word;
-
-	/* The tegra spi controller has a bug which causes the first word
-	 * in PIO transactions to be garbage.  Since packed DMA transactions
-	 * require transfers to be 4 byte aligned we need a bounce buffer
-	 * for the generic case.
-	 */
-	int			dma_req_len;
-#if defined(CONFIG_TEGRA_SYSTEM_DMA)
-	struct tegra_dma_req	rx_dma_req;
-	struct tegra_dma_channel *rx_dma;
-#else
-	struct dma_chan		*rx_dma;
-	struct dma_slave_config	sconfig;
-	struct dma_async_tx_descriptor	*rx_dma_desc;
-	dma_cookie_t		rx_cookie;
-#endif
-	u32			*rx_bb;
-	dma_addr_t		rx_bb_phys;
-};
-
-#if !defined(CONFIG_TEGRA_SYSTEM_DMA)
-static void tegra_spi_rx_dma_complete(void *args);
-#endif
-
-static inline unsigned long spi_tegra_readl(struct spi_tegra_data *tspi,
-					    unsigned long reg)
-{
-	return readl(tspi->base + reg);
-}
-
-static inline void spi_tegra_writel(struct spi_tegra_data *tspi,
-				    unsigned long val,
-				    unsigned long reg)
-{
-	writel(val, tspi->base + reg);
-}
-
-static void spi_tegra_go(struct spi_tegra_data *tspi)
-{
-	unsigned long val;
-
-	wmb();
-
-	val = spi_tegra_readl(tspi, SLINK_DMA_CTL);
-	val &= ~SLINK_DMA_BLOCK_SIZE(~0) & ~SLINK_DMA_EN;
-	val |= SLINK_DMA_BLOCK_SIZE(tspi->dma_req_len / 4 - 1);
-	spi_tegra_writel(tspi, val, SLINK_DMA_CTL);
-#if defined(CONFIG_TEGRA_SYSTEM_DMA)
-	tspi->rx_dma_req.size = tspi->dma_req_len;
-	tegra_dma_enqueue_req(tspi->rx_dma, &tspi->rx_dma_req);
-#else
-	tspi->rx_dma_desc = dmaengine_prep_slave_single(tspi->rx_dma,
-				tspi->rx_bb_phys, tspi->dma_req_len,
-				DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
-	if (!tspi->rx_dma_desc) {
-		dev_err(&tspi->pdev->dev, "dmaengine slave prep failed\n");
-		return;
-	}
-	tspi->rx_dma_desc->callback = tegra_spi_rx_dma_complete;
-	tspi->rx_dma_desc->callback_param = tspi;
-	tspi->rx_cookie = dmaengine_submit(tspi->rx_dma_desc);
-	dma_async_issue_pending(tspi->rx_dma);
-#endif
-
-	val |= SLINK_DMA_EN;
-	spi_tegra_writel(tspi, val, SLINK_DMA_CTL);
-}
-
-static unsigned spi_tegra_fill_tx_fifo(struct spi_tegra_data *tspi,
-				  struct spi_transfer *t)
-{
-	unsigned len = min(t->len - tspi->cur_pos, BB_LEN *
-			   tspi->cur_bytes_per_word);
-	u8 *tx_buf = (u8 *)t->tx_buf + tspi->cur_pos;
-	int i, j;
-	unsigned long val;
-
-	val = spi_tegra_readl(tspi, SLINK_COMMAND);
-	val &= ~SLINK_WORD_SIZE(~0);
-	val |= SLINK_WORD_SIZE(len / tspi->cur_bytes_per_word - 1);
-	spi_tegra_writel(tspi, val, SLINK_COMMAND);
-
-	for (i = 0; i < len; i += tspi->cur_bytes_per_word) {
-		val = 0;
-		for (j = 0; j < tspi->cur_bytes_per_word; j++)
-			val |= tx_buf[i + j] << j * 8;
-
-		spi_tegra_writel(tspi, val, SLINK_TX_FIFO);
-	}
-
-	tspi->dma_req_len = len / tspi->cur_bytes_per_word * 4;
-
-	return len;
-}
-
-static unsigned spi_tegra_drain_rx_fifo(struct spi_tegra_data *tspi,
-				  struct spi_transfer *t)
-{
-	unsigned len = tspi->cur_len;
-	u8 *rx_buf = (u8 *)t->rx_buf + tspi->cur_pos;
-	int i, j;
-	unsigned long val;
-
-	for (i = 0; i < len; i += tspi->cur_bytes_per_word) {
-		val = tspi->rx_bb[i / tspi->cur_bytes_per_word];
-		for (j = 0; j < tspi->cur_bytes_per_word; j++)
-			rx_buf[i + j] = (val >> (j * 8)) & 0xff;
-	}
-
-	return len;
-}
-
-static void spi_tegra_start_transfer(struct spi_device *spi,
-				    struct spi_transfer *t)
-{
-	struct spi_tegra_data *tspi = spi_master_get_devdata(spi->master);
-	u32 speed;
-	u8 bits_per_word;
-	unsigned long val;
-
-	speed = t->speed_hz ? t->speed_hz : spi->max_speed_hz;
-	bits_per_word = t->bits_per_word ? t->bits_per_word  :
-		spi->bits_per_word;
-
-	tspi->cur_bytes_per_word = (bits_per_word - 1) / 8 + 1;
-
-	if (speed != tspi->cur_speed)
-		clk_set_rate(tspi->clk, speed);
-
-	if (tspi->cur_speed == 0)
-		clk_prepare_enable(tspi->clk);
-
-	tspi->cur_speed = speed;
-
-	val = spi_tegra_readl(tspi, SLINK_COMMAND2);
-	val &= ~SLINK_SS_EN_CS(~0) | SLINK_RXEN | SLINK_TXEN;
-	if (t->rx_buf)
-		val |= SLINK_RXEN;
-	if (t->tx_buf)
-		val |= SLINK_TXEN;
-	val |= SLINK_SS_EN_CS(spi->chip_select);
-	val |= SLINK_SPIE;
-	spi_tegra_writel(tspi, val, SLINK_COMMAND2);
-
-	val = spi_tegra_readl(tspi, SLINK_COMMAND);
-	val &= ~SLINK_BIT_LENGTH(~0);
-	val |= SLINK_BIT_LENGTH(bits_per_word - 1);
-
-	/* FIXME: should probably control CS manually so that we can be sure
-	 * it does not go low between transfer and to support delay_usecs
-	 * correctly.
-	 */
-	val &= ~SLINK_IDLE_SCLK_MASK & ~SLINK_CK_SDA & ~SLINK_CS_SW;
-
-	if (spi->mode & SPI_CPHA)
-		val |= SLINK_CK_SDA;
-
-	if (spi->mode & SPI_CPOL)
-		val |= SLINK_IDLE_SCLK_DRIVE_HIGH;
-	else
-		val |= SLINK_IDLE_SCLK_DRIVE_LOW;
-
-	val |= SLINK_M_S;
-
-	spi_tegra_writel(tspi, val, SLINK_COMMAND);
-
-	spi_tegra_writel(tspi, SLINK_RX_FLUSH | SLINK_TX_FLUSH, SLINK_STATUS);
-
-	tspi->cur = t;
-	tspi->cur_pos = 0;
-	tspi->cur_len = spi_tegra_fill_tx_fifo(tspi, t);
-
-	spi_tegra_go(tspi);
-}
-
-static void spi_tegra_start_message(struct spi_device *spi,
-				    struct spi_message *m)
-{
-	struct spi_transfer *t;
-
-	m->actual_length = 0;
-	m->status = 0;
-
-	t = list_first_entry(&m->transfers, struct spi_transfer, transfer_list);
-	spi_tegra_start_transfer(spi, t);
-}
-
-static void handle_spi_rx_dma_complete(struct spi_tegra_data *tspi)
-{
-	unsigned long flags;
-	struct spi_message *m;
-	struct spi_device *spi;
-	int timeout = 0;
-	unsigned long val;
-
-	/* the SPI controller may come back with both the BSY and RDY bits
-	 * set.  In this case we need to wait for the BSY bit to clear so
-	 * that we are sure the DMA is finished.  1000 reads was empirically
-	 * determined to be long enough.
-	 */
-	while (timeout++ < 1000) {
-		if (!(spi_tegra_readl(tspi, SLINK_STATUS) & SLINK_BSY))
-			break;
-	}
-
-	spin_lock_irqsave(&tspi->lock, flags);
-
-	val = spi_tegra_readl(tspi, SLINK_STATUS);
-	val |= SLINK_RDY;
-	spi_tegra_writel(tspi, val, SLINK_STATUS);
-
-	m = list_first_entry(&tspi->queue, struct spi_message, queue);
-
-	if (timeout >= 1000)
-		m->status = -EIO;
-
-	spi = m->state;
-
-	tspi->cur_pos += spi_tegra_drain_rx_fifo(tspi, tspi->cur);
-	m->actual_length += tspi->cur_pos;
-
-	if (tspi->cur_pos < tspi->cur->len) {
-		tspi->cur_len = spi_tegra_fill_tx_fifo(tspi, tspi->cur);
-		spi_tegra_go(tspi);
-	} else if (!list_is_last(&tspi->cur->transfer_list,
-				 &m->transfers)) {
-		tspi->cur =  list_first_entry(&tspi->cur->transfer_list,
-					      struct spi_transfer,
-					      transfer_list);
-		spi_tegra_start_transfer(spi, tspi->cur);
-	} else {
-		list_del(&m->queue);
-
-		m->complete(m->context);
-
-		if (!list_empty(&tspi->queue)) {
-			m = list_first_entry(&tspi->queue, struct spi_message,
-					     queue);
-			spi = m->state;
-			spi_tegra_start_message(spi, m);
-		} else {
-			clk_disable_unprepare(tspi->clk);
-			tspi->cur_speed = 0;
-		}
-	}
-
-	spin_unlock_irqrestore(&tspi->lock, flags);
-}
-#if defined(CONFIG_TEGRA_SYSTEM_DMA)
-static void tegra_spi_rx_dma_complete(struct tegra_dma_req *req)
-{
-	struct spi_tegra_data *tspi = req->dev;
-	handle_spi_rx_dma_complete(tspi);
-}
-#else
-static void tegra_spi_rx_dma_complete(void *args)
-{
-	struct spi_tegra_data *tspi = args;
-	handle_spi_rx_dma_complete(tspi);
-}
-#endif
-
-static int spi_tegra_setup(struct spi_device *spi)
-{
-	struct spi_tegra_data *tspi = spi_master_get_devdata(spi->master);
-	unsigned long cs_bit;
-	unsigned long val;
-	unsigned long flags;
-
-	dev_dbg(&spi->dev, "setup %d bpw, %scpol, %scpha, %dHz\n",
-		spi->bits_per_word,
-		spi->mode & SPI_CPOL ? "" : "~",
-		spi->mode & SPI_CPHA ? "" : "~",
-		spi->max_speed_hz);
-
-
-	switch (spi->chip_select) {
-	case 0:
-		cs_bit = SLINK_CS_POLARITY;
-		break;
-
-	case 1:
-		cs_bit = SLINK_CS_POLARITY1;
-		break;
-
-	case 2:
-		cs_bit = SLINK_CS_POLARITY2;
-		break;
-
-	case 4:
-		cs_bit = SLINK_CS_POLARITY3;
-		break;
-
-	default:
-		return -EINVAL;
-	}
-
-	spin_lock_irqsave(&tspi->lock, flags);
-
-	val = spi_tegra_readl(tspi, SLINK_COMMAND);
-	if (spi->mode & SPI_CS_HIGH)
-		val |= cs_bit;
-	else
-		val &= ~cs_bit;
-	spi_tegra_writel(tspi, val, SLINK_COMMAND);
-
-	spin_unlock_irqrestore(&tspi->lock, flags);
-
-	return 0;
-}
-
-static int spi_tegra_transfer(struct spi_device *spi, struct spi_message *m)
-{
-	struct spi_tegra_data *tspi = spi_master_get_devdata(spi->master);
-	struct spi_transfer *t;
-	unsigned long flags;
-	int was_empty;
-
-	if (list_empty(&m->transfers) || !m->complete)
-		return -EINVAL;
-
-	list_for_each_entry(t, &m->transfers, transfer_list) {
-		if (t->bits_per_word < 0 || t->bits_per_word > 32)
-			return -EINVAL;
-
-		if (t->len == 0)
-			return -EINVAL;
-
-		if (!t->rx_buf && !t->tx_buf)
-			return -EINVAL;
-	}
-
-	m->state = spi;
-
-	spin_lock_irqsave(&tspi->lock, flags);
-	was_empty = list_empty(&tspi->queue);
-	list_add_tail(&m->queue, &tspi->queue);
-
-	if (was_empty)
-		spi_tegra_start_message(spi, m);
-
-	spin_unlock_irqrestore(&tspi->lock, flags);
-
-	return 0;
-}
-
-static int __devinit spi_tegra_probe(struct platform_device *pdev)
-{
-	struct spi_master	*master;
-	struct spi_tegra_data	*tspi;
-	struct resource		*r;
-	int ret;
-#if !defined(CONFIG_TEGRA_SYSTEM_DMA)
-	dma_cap_mask_t mask;
-#endif
-
-	master = spi_alloc_master(&pdev->dev, sizeof *tspi);
-	if (master == NULL) {
-		dev_err(&pdev->dev, "master allocation failed\n");
-		return -ENOMEM;
-	}
-
-	/* the spi->mode bits understood by this driver: */
-	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
-
-	master->bus_num = pdev->id;
-
-	master->setup = spi_tegra_setup;
-	master->transfer = spi_tegra_transfer;
-	master->num_chipselect = 4;
-
-	dev_set_drvdata(&pdev->dev, master);
-	tspi = spi_master_get_devdata(master);
-	tspi->master = master;
-	tspi->pdev = pdev;
-	spin_lock_init(&tspi->lock);
-
-	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (r == NULL) {
-		ret = -ENODEV;
-		goto err0;
-	}
-
-	if (!request_mem_region(r->start, resource_size(r),
-				dev_name(&pdev->dev))) {
-		ret = -EBUSY;
-		goto err0;
-	}
-
-	tspi->phys = r->start;
-	tspi->base = ioremap(r->start, resource_size(r));
-	if (!tspi->base) {
-		dev_err(&pdev->dev, "can't ioremap iomem\n");
-		ret = -ENOMEM;
-		goto err1;
-	}
-
-	tspi->clk = clk_get(&pdev->dev, NULL);
-	if (IS_ERR(tspi->clk)) {
-		dev_err(&pdev->dev, "can not get clock\n");
-		ret = PTR_ERR(tspi->clk);
-		goto err2;
-	}
-
-	INIT_LIST_HEAD(&tspi->queue);
-
-#if defined(CONFIG_TEGRA_SYSTEM_DMA)
-	tspi->rx_dma = tegra_dma_allocate_channel(TEGRA_DMA_MODE_ONESHOT);
-	if (!tspi->rx_dma) {
-		dev_err(&pdev->dev, "can not allocate rx dma channel\n");
-		ret = -ENODEV;
-		goto err3;
-	}
-#else
-	dma_cap_zero(mask);
-	dma_cap_set(DMA_SLAVE, mask);
-	tspi->rx_dma = dma_request_channel(mask, NULL, NULL);
-	if (!tspi->rx_dma) {
-		dev_err(&pdev->dev, "can not allocate rx dma channel\n");
-		ret = -ENODEV;
-		goto err3;
-	}
-
-#endif
-
-	tspi->rx_bb = dma_alloc_coherent(&pdev->dev, sizeof(u32) * BB_LEN,
-					 &tspi->rx_bb_phys, GFP_KERNEL);
-	if (!tspi->rx_bb) {
-		dev_err(&pdev->dev, "can not allocate rx bounce buffer\n");
-		ret = -ENOMEM;
-		goto err4;
-	}
-
-#if defined(CONFIG_TEGRA_SYSTEM_DMA)
-	tspi->rx_dma_req.complete = tegra_spi_rx_dma_complete;
-	tspi->rx_dma_req.to_memory = 1;
-	tspi->rx_dma_req.dest_addr = tspi->rx_bb_phys;
-	tspi->rx_dma_req.dest_bus_width = 32;
-	tspi->rx_dma_req.source_addr = tspi->phys + SLINK_RX_FIFO;
-	tspi->rx_dma_req.source_bus_width = 32;
-	tspi->rx_dma_req.source_wrap = 4;
-	tspi->rx_dma_req.req_sel = spi_tegra_req_sels[pdev->id];
-	tspi->rx_dma_req.dev = tspi;
-#else
-	/* Dmaengine Dma slave config */
-	tspi->sconfig.src_addr = tspi->phys + SLINK_RX_FIFO;
-	tspi->sconfig.dst_addr = tspi->phys + SLINK_RX_FIFO;
-	tspi->sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
-	tspi->sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
-	tspi->sconfig.slave_id = spi_tegra_req_sels[pdev->id];
-	tspi->sconfig.src_maxburst = 1;
-	tspi->sconfig.dst_maxburst = 1;
-	ret = dmaengine_device_control(tspi->rx_dma,
-			DMA_SLAVE_CONFIG, (unsigned long) &tspi->sconfig);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "can not do slave configure for dma %d\n",
-			ret);
-		goto err4;
-	}
-#endif
-
-	master->dev.of_node = pdev->dev.of_node;
-	ret = spi_register_master(master);
-
-	if (ret < 0)
-		goto err5;
-
-	return ret;
-
-err5:
-	dma_free_coherent(&pdev->dev, sizeof(u32) * BB_LEN,
-			  tspi->rx_bb, tspi->rx_bb_phys);
-err4:
-#if defined(CONFIG_TEGRA_SYSTEM_DMA)
-	tegra_dma_free_channel(tspi->rx_dma);
-#else
-	dma_release_channel(tspi->rx_dma);
-#endif
-err3:
-	clk_put(tspi->clk);
-err2:
-	iounmap(tspi->base);
-err1:
-	release_mem_region(r->start, resource_size(r));
-err0:
-	spi_master_put(master);
-	return ret;
-}
-
-static int __devexit spi_tegra_remove(struct platform_device *pdev)
-{
-	struct spi_master	*master;
-	struct spi_tegra_data	*tspi;
-	struct resource		*r;
-
-	master = spi_master_get(dev_get_drvdata(&pdev->dev));
-	tspi = spi_master_get_devdata(master);
-
-	spi_unregister_master(master);
-#if defined(CONFIG_TEGRA_SYSTEM_DMA)
-	tegra_dma_free_channel(tspi->rx_dma);
-#else
-	dma_release_channel(tspi->rx_dma);
-#endif
-
-	dma_free_coherent(&pdev->dev, sizeof(u32) * BB_LEN,
-			  tspi->rx_bb, tspi->rx_bb_phys);
-
-	clk_put(tspi->clk);
-	iounmap(tspi->base);
-
-	spi_master_put(master);
-
-	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	release_mem_region(r->start, resource_size(r));
-
-	return 0;
-}
-
-MODULE_ALIAS("platform:spi_tegra");
-
-#ifdef CONFIG_OF
-static struct of_device_id spi_tegra_of_match_table[] __devinitdata = {
-	{ .compatible = "nvidia,tegra20-spi", },
-	{}
-};
-MODULE_DEVICE_TABLE(of, spi_tegra_of_match_table);
-#else /* CONFIG_OF */
-#define spi_tegra_of_match_table NULL
-#endif /* CONFIG_OF */
-
-static struct platform_driver spi_tegra_driver = {
-	.driver = {
-		.name =		"spi_tegra",
-		.owner =	THIS_MODULE,
-		.of_match_table = spi_tegra_of_match_table,
-	},
-	.probe =	spi_tegra_probe,
-	.remove =	__devexit_p(spi_tegra_remove),
-};
-module_platform_driver(spi_tegra_driver);
-
-MODULE_LICENSE("GPL");