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@@ -0,0 +1,651 @@
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+/*
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+ * (C) Copyright 2009-2010
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+ * Nokia Siemens Networks, michael.lawnick.ext@nsn.com
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+ *
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+ * Portions Copyright (C) 2010 Cavium Networks, Inc.
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+ *
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+ * This is a driver for the i2c adapter in Cavium Networks' OCTEON processors.
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+ *
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+ * This file is licensed under the terms of the GNU General Public
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+ * License version 2. This program is licensed "as is" without any
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+ * warranty of any kind, whether express or implied.
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+ */
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+
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+#include <linux/kernel.h>
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+#include <linux/module.h>
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+#include <linux/sched.h>
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+#include <linux/init.h>
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+
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+#include <linux/io.h>
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+#include <linux/i2c.h>
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+#include <linux/interrupt.h>
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+#include <linux/delay.h>
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+#include <linux/platform_device.h>
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+
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+#include <asm/octeon/octeon.h>
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+
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+#define DRV_NAME "i2c-octeon"
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+
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+/* The previous out-of-tree version was implicitly version 1.0. */
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+#define DRV_VERSION "2.0"
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+
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+/* register offsets */
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+#define SW_TWSI 0x00
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+#define TWSI_INT 0x10
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+
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+/* Controller command patterns */
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+#define SW_TWSI_V 0x8000000000000000ull
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+#define SW_TWSI_EOP_TWSI_DATA 0x0C00000100000000ull
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+#define SW_TWSI_EOP_TWSI_CTL 0x0C00000200000000ull
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+#define SW_TWSI_EOP_TWSI_CLKCTL 0x0C00000300000000ull
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+#define SW_TWSI_EOP_TWSI_STAT 0x0C00000300000000ull
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+#define SW_TWSI_EOP_TWSI_RST 0x0C00000700000000ull
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+#define SW_TWSI_OP_TWSI_CLK 0x0800000000000000ull
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+#define SW_TWSI_R 0x0100000000000000ull
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+
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+/* Controller command and status bits */
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+#define TWSI_CTL_CE 0x80
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+#define TWSI_CTL_ENAB 0x40
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+#define TWSI_CTL_STA 0x20
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+#define TWSI_CTL_STP 0x10
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+#define TWSI_CTL_IFLG 0x08
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+#define TWSI_CTL_AAK 0x04
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+
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+/* Some status values */
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+#define STAT_START 0x08
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+#define STAT_RSTART 0x10
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+#define STAT_TXADDR_ACK 0x18
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+#define STAT_TXDATA_ACK 0x28
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+#define STAT_RXADDR_ACK 0x40
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+#define STAT_RXDATA_ACK 0x50
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+#define STAT_IDLE 0xF8
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+
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+struct octeon_i2c {
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+ wait_queue_head_t queue;
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+ struct i2c_adapter adap;
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+ int irq;
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+ int twsi_freq;
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+ int sys_freq;
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+ resource_size_t twsi_phys;
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+ void __iomem *twsi_base;
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+ resource_size_t regsize;
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+ struct device *dev;
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+};
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+
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+/**
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+ * octeon_i2c_write_sw - write an I2C core register.
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+ * @i2c: The struct octeon_i2c.
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+ * @eop_reg: Register selector.
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+ * @data: Value to be written.
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+ *
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+ * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
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+ */
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+static void octeon_i2c_write_sw(struct octeon_i2c *i2c,
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+ u64 eop_reg,
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+ u8 data)
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+{
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+ u64 tmp;
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+
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+ __raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + SW_TWSI);
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+ do {
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+ tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
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+ } while ((tmp & SW_TWSI_V) != 0);
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+}
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+
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+/**
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+ * octeon_i2c_read_sw - write an I2C core register.
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+ * @i2c: The struct octeon_i2c.
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+ * @eop_reg: Register selector.
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+ *
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+ * Returns the data.
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+ *
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+ * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
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+ */
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+static u8 octeon_i2c_read_sw(struct octeon_i2c *i2c, u64 eop_reg)
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+{
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+ u64 tmp;
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+
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+ __raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base + SW_TWSI);
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+ do {
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+ tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
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+ } while ((tmp & SW_TWSI_V) != 0);
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+
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+ return tmp & 0xFF;
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+}
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+
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+/**
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+ * octeon_i2c_write_int - write the TWSI_INT register
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+ * @i2c: The struct octeon_i2c.
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+ * @data: Value to be written.
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+ */
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+static void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
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+{
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+ u64 tmp;
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+
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+ __raw_writeq(data, i2c->twsi_base + TWSI_INT);
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+ tmp = __raw_readq(i2c->twsi_base + TWSI_INT);
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+}
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+
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+/**
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+ * octeon_i2c_int_enable - enable the TS interrupt.
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+ * @i2c: The struct octeon_i2c.
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+ *
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+ * The interrupt will be asserted when there is non-STAT_IDLE state in
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+ * the SW_TWSI_EOP_TWSI_STAT register.
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+ */
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+static void octeon_i2c_int_enable(struct octeon_i2c *i2c)
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+{
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+ octeon_i2c_write_int(i2c, 0x40);
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+}
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+
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+/**
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+ * octeon_i2c_int_disable - disable the TS interrupt.
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+ * @i2c: The struct octeon_i2c.
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+ */
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+static void octeon_i2c_int_disable(struct octeon_i2c *i2c)
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+{
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+ octeon_i2c_write_int(i2c, 0);
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+}
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+
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+/**
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+ * octeon_i2c_unblock - unblock the bus.
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+ * @i2c: The struct octeon_i2c.
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+ *
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+ * If there was a reset while a device was driving 0 to bus,
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+ * bus is blocked. We toggle it free manually by some clock
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+ * cycles and send a stop.
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+ */
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+static void octeon_i2c_unblock(struct octeon_i2c *i2c)
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+{
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+ int i;
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+
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+ dev_dbg(i2c->dev, "%s\n", __func__);
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+ for (i = 0; i < 9; i++) {
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+ octeon_i2c_write_int(i2c, 0x0);
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+ udelay(5);
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+ octeon_i2c_write_int(i2c, 0x200);
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+ udelay(5);
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+ }
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+ octeon_i2c_write_int(i2c, 0x300);
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+ udelay(5);
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+ octeon_i2c_write_int(i2c, 0x100);
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+ udelay(5);
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+ octeon_i2c_write_int(i2c, 0x0);
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+}
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+
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+/**
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+ * octeon_i2c_isr - the interrupt service routine.
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+ * @int: The irq, unused.
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+ * @dev_id: Our struct octeon_i2c.
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+ */
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+static irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
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+{
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+ struct octeon_i2c *i2c = dev_id;
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+
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+ octeon_i2c_int_disable(i2c);
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+ wake_up_interruptible(&i2c->queue);
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+
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+ return IRQ_HANDLED;
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+}
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+
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+
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+static int octeon_i2c_test_iflg(struct octeon_i2c *i2c)
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+{
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+ return (octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_CTL) & TWSI_CTL_IFLG) != 0;
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+}
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+
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+/**
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+ * octeon_i2c_wait - wait for the IFLG to be set.
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+ * @i2c: The struct octeon_i2c.
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+ *
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+ * Returns 0 on success, otherwise a negative errno.
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+ */
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+static int octeon_i2c_wait(struct octeon_i2c *i2c)
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+{
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+ int result;
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+
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+ octeon_i2c_int_enable(i2c);
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+
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+ result = wait_event_interruptible_timeout(i2c->queue,
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+ octeon_i2c_test_iflg(i2c),
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+ i2c->adap.timeout);
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+
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+ octeon_i2c_int_disable(i2c);
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+
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+ if (result < 0) {
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+ dev_dbg(i2c->dev, "%s: wait interrupted\n", __func__);
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+ return result;
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+ } else if (result == 0) {
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+ dev_dbg(i2c->dev, "%s: timeout\n", __func__);
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+ result = -ETIMEDOUT;
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+ }
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+
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+ return 0;
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+}
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+
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+/**
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+ * octeon_i2c_start - send START to the bus.
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+ * @i2c: The struct octeon_i2c.
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+ *
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+ * Returns 0 on success, otherwise a negative errno.
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+ */
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+static int octeon_i2c_start(struct octeon_i2c *i2c)
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+{
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+ u8 data;
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+ int result;
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+
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+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
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+ TWSI_CTL_ENAB | TWSI_CTL_STA);
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+
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+ result = octeon_i2c_wait(i2c);
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+ if (result) {
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+ if (octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT) == STAT_IDLE) {
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+ /*
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+ * Controller refused to send start flag May
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+ * be a client is holding SDA low - let's try
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+ * to free it.
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+ */
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+ octeon_i2c_unblock(i2c);
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+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
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+ TWSI_CTL_ENAB | TWSI_CTL_STA);
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+
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+ result = octeon_i2c_wait(i2c);
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+ }
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+ if (result)
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+ return result;
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+ }
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+
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+ data = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
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+ if ((data != STAT_START) && (data != STAT_RSTART)) {
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+ dev_err(i2c->dev, "%s: bad status (0x%x)\n", __func__, data);
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+ return -EIO;
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+ }
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+
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+ return 0;
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+}
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+
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+/**
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+ * octeon_i2c_stop - send STOP to the bus.
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+ * @i2c: The struct octeon_i2c.
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+ *
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+ * Returns 0 on success, otherwise a negative errno.
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+ */
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+static int octeon_i2c_stop(struct octeon_i2c *i2c)
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+{
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+ u8 data;
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+
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+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
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+ TWSI_CTL_ENAB | TWSI_CTL_STP);
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+
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+ data = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
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+
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+ if (data != STAT_IDLE) {
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+ dev_err(i2c->dev, "%s: bad status(0x%x)\n", __func__, data);
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+ return -EIO;
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+ }
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+ return 0;
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+}
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+
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+/**
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+ * octeon_i2c_write - send data to the bus.
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+ * @i2c: The struct octeon_i2c.
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+ * @target: Target address.
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+ * @data: Pointer to the data to be sent.
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+ * @length: Length of the data.
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+ *
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+ * The address is sent over the bus, then the data.
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+ *
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+ * Returns 0 on success, otherwise a negative errno.
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+ */
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+static int octeon_i2c_write(struct octeon_i2c *i2c, int target,
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+ const u8 *data, int length)
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+{
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+ int i, result;
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+ u8 tmp;
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+
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+ result = octeon_i2c_start(i2c);
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+ if (result)
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+ return result;
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+
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+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, target << 1);
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+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
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+
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+ result = octeon_i2c_wait(i2c);
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+ if (result)
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+ return result;
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+
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+ for (i = 0; i < length; i++) {
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+ tmp = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
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+ if ((tmp != STAT_TXADDR_ACK) && (tmp != STAT_TXDATA_ACK)) {
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+ dev_err(i2c->dev,
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+ "%s: bad status before write (0x%x)\n",
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+ __func__, tmp);
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+ return -EIO;
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+ }
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+
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+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, data[i]);
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+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
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+
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+ result = octeon_i2c_wait(i2c);
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+ if (result)
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+ return result;
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+ }
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+
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+ return 0;
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+}
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+
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+/**
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+ * octeon_i2c_read - receive data from the bus.
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+ * @i2c: The struct octeon_i2c.
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+ * @target: Target address.
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|
|
+ * @data: Pointer to the location to store the datae .
|
|
|
|
+ * @length: Length of the data.
|
|
|
|
+ *
|
|
|
|
+ * The address is sent over the bus, then the data is read.
|
|
|
|
+ *
|
|
|
|
+ * Returns 0 on success, otherwise a negative errno.
|
|
|
|
+ */
|
|
|
|
+static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
|
|
|
|
+ u8 *data, int length)
|
|
|
|
+{
|
|
|
|
+ int i, result;
|
|
|
|
+ u8 tmp;
|
|
|
|
+
|
|
|
|
+ if (length < 1)
|
|
|
|
+ return -EINVAL;
|
|
|
|
+
|
|
|
|
+ result = octeon_i2c_start(i2c);
|
|
|
|
+ if (result)
|
|
|
|
+ return result;
|
|
|
|
+
|
|
|
|
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, (target<<1) | 1);
|
|
|
|
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
|
|
|
|
+
|
|
|
|
+ result = octeon_i2c_wait(i2c);
|
|
|
|
+ if (result)
|
|
|
|
+ return result;
|
|
|
|
+
|
|
|
|
+ for (i = 0; i < length; i++) {
|
|
|
|
+ tmp = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
|
|
|
|
+ if ((tmp != STAT_RXDATA_ACK) && (tmp != STAT_RXADDR_ACK)) {
|
|
|
|
+ dev_err(i2c->dev,
|
|
|
|
+ "%s: bad status before read (0x%x)\n",
|
|
|
|
+ __func__, tmp);
|
|
|
|
+ return -EIO;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ if (i+1 < length)
|
|
|
|
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
|
|
|
|
+ TWSI_CTL_ENAB | TWSI_CTL_AAK);
|
|
|
|
+ else
|
|
|
|
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
|
|
|
|
+ TWSI_CTL_ENAB);
|
|
|
|
+
|
|
|
|
+ result = octeon_i2c_wait(i2c);
|
|
|
|
+ if (result)
|
|
|
|
+ return result;
|
|
|
|
+
|
|
|
|
+ data[i] = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_DATA);
|
|
|
|
+ }
|
|
|
|
+ return 0;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+/**
|
|
|
|
+ * octeon_i2c_xfer - The driver's master_xfer function.
|
|
|
|
+ * @adap: Pointer to the i2c_adapter structure.
|
|
|
|
+ * @msgs: Pointer to the messages to be processed.
|
|
|
|
+ * @num: Length of the MSGS array.
|
|
|
|
+ *
|
|
|
|
+ * Returns the number of messages processed, or a negative errno on
|
|
|
|
+ * failure.
|
|
|
|
+ */
|
|
|
|
+static int octeon_i2c_xfer(struct i2c_adapter *adap,
|
|
|
|
+ struct i2c_msg *msgs,
|
|
|
|
+ int num)
|
|
|
|
+{
|
|
|
|
+ struct i2c_msg *pmsg;
|
|
|
|
+ int i;
|
|
|
|
+ int ret = 0;
|
|
|
|
+ struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
|
|
|
+
|
|
|
|
+ for (i = 0; ret == 0 && i < num; i++) {
|
|
|
|
+ pmsg = &msgs[i];
|
|
|
|
+ dev_dbg(i2c->dev,
|
|
|
|
+ "Doing %s %d byte(s) to/from 0x%02x - %d of %d messages\n",
|
|
|
|
+ pmsg->flags & I2C_M_RD ? "read" : "write",
|
|
|
|
+ pmsg->len, pmsg->addr, i + 1, num);
|
|
|
|
+ if (pmsg->flags & I2C_M_RD)
|
|
|
|
+ ret = octeon_i2c_read(i2c, pmsg->addr, pmsg->buf,
|
|
|
|
+ pmsg->len);
|
|
|
|
+ else
|
|
|
|
+ ret = octeon_i2c_write(i2c, pmsg->addr, pmsg->buf,
|
|
|
|
+ pmsg->len);
|
|
|
|
+ }
|
|
|
|
+ octeon_i2c_stop(i2c);
|
|
|
|
+
|
|
|
|
+ return (ret != 0) ? ret : num;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static u32 octeon_i2c_functionality(struct i2c_adapter *adap)
|
|
|
|
+{
|
|
|
|
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static const struct i2c_algorithm octeon_i2c_algo = {
|
|
|
|
+ .master_xfer = octeon_i2c_xfer,
|
|
|
|
+ .functionality = octeon_i2c_functionality,
|
|
|
|
+};
|
|
|
|
+
|
|
|
|
+static struct i2c_adapter octeon_i2c_ops = {
|
|
|
|
+ .owner = THIS_MODULE,
|
|
|
|
+ .name = "OCTEON adapter",
|
|
|
|
+ .algo = &octeon_i2c_algo,
|
|
|
|
+ .timeout = 2,
|
|
|
|
+};
|
|
|
|
+
|
|
|
|
+/**
|
|
|
|
+ * octeon_i2c_setclock - Calculate and set clock divisors.
|
|
|
|
+ */
|
|
|
|
+static int __init octeon_i2c_setclock(struct octeon_i2c *i2c)
|
|
|
|
+{
|
|
|
|
+ int tclk, thp_base, inc, thp_idx, mdiv_idx, ndiv_idx, foscl, diff;
|
|
|
|
+ int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = 1000000;
|
|
|
|
+
|
|
|
|
+ for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
|
|
|
|
+ /*
|
|
|
|
+ * An mdiv value of less than 2 seems to not work well
|
|
|
|
+ * with ds1337 RTCs, so we constrain it to larger
|
|
|
|
+ * values.
|
|
|
|
+ */
|
|
|
|
+ for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
|
|
|
|
+ /*
|
|
|
|
+ * For given ndiv and mdiv values check the
|
|
|
|
+ * two closest thp values.
|
|
|
|
+ */
|
|
|
|
+ tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
|
|
|
|
+ tclk *= (1 << ndiv_idx);
|
|
|
|
+ thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
|
|
|
|
+ for (inc = 0; inc <= 1; inc++) {
|
|
|
|
+ thp_idx = thp_base + inc;
|
|
|
|
+ if (thp_idx < 5 || thp_idx > 0xff)
|
|
|
|
+ continue;
|
|
|
|
+
|
|
|
|
+ foscl = i2c->sys_freq / (2 * (thp_idx + 1));
|
|
|
|
+ foscl = foscl / (1 << ndiv_idx);
|
|
|
|
+ foscl = foscl / (mdiv_idx + 1) / 10;
|
|
|
|
+ diff = abs(foscl - i2c->twsi_freq);
|
|
|
|
+ if (diff < delta_hz) {
|
|
|
|
+ delta_hz = diff;
|
|
|
|
+ thp = thp_idx;
|
|
|
|
+ mdiv = mdiv_idx;
|
|
|
|
+ ndiv = ndiv_idx;
|
|
|
|
+ }
|
|
|
|
+ }
|
|
|
|
+ }
|
|
|
|
+ }
|
|
|
|
+ octeon_i2c_write_sw(i2c, SW_TWSI_OP_TWSI_CLK, thp);
|
|
|
|
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
|
|
|
|
+
|
|
|
|
+ return 0;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static int __init octeon_i2c_initlowlevel(struct octeon_i2c *i2c)
|
|
|
|
+{
|
|
|
|
+ u8 status;
|
|
|
|
+ int tries;
|
|
|
|
+
|
|
|
|
+ /* disable high level controller, enable bus access */
|
|
|
|
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
|
|
|
|
+
|
|
|
|
+ /* reset controller */
|
|
|
|
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_RST, 0);
|
|
|
|
+
|
|
|
|
+ for (tries = 10; tries; tries--) {
|
|
|
|
+ udelay(1);
|
|
|
|
+ status = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
|
|
|
|
+ if (status == STAT_IDLE)
|
|
|
|
+ return 0;
|
|
|
|
+ }
|
|
|
|
+ dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n", __func__, status);
|
|
|
|
+ return -EIO;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static int __devinit octeon_i2c_probe(struct platform_device *pdev)
|
|
|
|
+{
|
|
|
|
+ int irq, result = 0;
|
|
|
|
+ struct octeon_i2c *i2c;
|
|
|
|
+ struct octeon_i2c_data *i2c_data;
|
|
|
|
+ struct resource *res_mem;
|
|
|
|
+
|
|
|
|
+ /* All adaptors have an irq. */
|
|
|
|
+ irq = platform_get_irq(pdev, 0);
|
|
|
|
+ if (irq < 0)
|
|
|
|
+ return irq;
|
|
|
|
+
|
|
|
|
+ i2c = kzalloc(sizeof(*i2c), GFP_KERNEL);
|
|
|
|
+ if (!i2c) {
|
|
|
|
+ dev_err(&pdev->dev, "kzalloc failed\n");
|
|
|
|
+ result = -ENOMEM;
|
|
|
|
+ goto out;
|
|
|
|
+ }
|
|
|
|
+ i2c->dev = &pdev->dev;
|
|
|
|
+ i2c_data = pdev->dev.platform_data;
|
|
|
|
+
|
|
|
|
+ res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
|
|
+
|
|
|
|
+ if (res_mem == NULL) {
|
|
|
|
+ dev_err(i2c->dev, "found no memory resource\n");
|
|
|
|
+ result = -ENXIO;
|
|
|
|
+ goto fail_region;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ if (i2c_data == NULL) {
|
|
|
|
+ dev_err(i2c->dev, "no I2C frequency data\n");
|
|
|
|
+ result = -ENXIO;
|
|
|
|
+ goto fail_region;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ i2c->twsi_phys = res_mem->start;
|
|
|
|
+ i2c->regsize = resource_size(res_mem);
|
|
|
|
+ i2c->twsi_freq = i2c_data->i2c_freq;
|
|
|
|
+ i2c->sys_freq = i2c_data->sys_freq;
|
|
|
|
+
|
|
|
|
+ if (!request_mem_region(i2c->twsi_phys, i2c->regsize, res_mem->name)) {
|
|
|
|
+ dev_err(i2c->dev, "request_mem_region failed\n");
|
|
|
|
+ goto fail_region;
|
|
|
|
+ }
|
|
|
|
+ i2c->twsi_base = ioremap(i2c->twsi_phys, i2c->regsize);
|
|
|
|
+
|
|
|
|
+ init_waitqueue_head(&i2c->queue);
|
|
|
|
+
|
|
|
|
+ i2c->irq = irq;
|
|
|
|
+
|
|
|
|
+ result = request_irq(i2c->irq, octeon_i2c_isr, 0, DRV_NAME, i2c);
|
|
|
|
+ if (result < 0) {
|
|
|
|
+ dev_err(i2c->dev, "failed to attach interrupt\n");
|
|
|
|
+ goto fail_irq;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ result = octeon_i2c_initlowlevel(i2c);
|
|
|
|
+ if (result) {
|
|
|
|
+ dev_err(i2c->dev, "init low level failed\n");
|
|
|
|
+ goto fail_add;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ result = octeon_i2c_setclock(i2c);
|
|
|
|
+ if (result) {
|
|
|
|
+ dev_err(i2c->dev, "clock init failed\n");
|
|
|
|
+ goto fail_add;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ i2c->adap = octeon_i2c_ops;
|
|
|
|
+ i2c->adap.dev.parent = &pdev->dev;
|
|
|
|
+ i2c->adap.nr = pdev->id >= 0 ? pdev->id : 0;
|
|
|
|
+ i2c_set_adapdata(&i2c->adap, i2c);
|
|
|
|
+ platform_set_drvdata(pdev, i2c);
|
|
|
|
+
|
|
|
|
+ result = i2c_add_numbered_adapter(&i2c->adap);
|
|
|
|
+ if (result < 0) {
|
|
|
|
+ dev_err(i2c->dev, "failed to add adapter\n");
|
|
|
|
+ goto fail_add;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ dev_info(i2c->dev, "version %s\n", DRV_VERSION);
|
|
|
|
+
|
|
|
|
+ return result;
|
|
|
|
+
|
|
|
|
+fail_add:
|
|
|
|
+ platform_set_drvdata(pdev, NULL);
|
|
|
|
+ free_irq(i2c->irq, i2c);
|
|
|
|
+fail_irq:
|
|
|
|
+ iounmap(i2c->twsi_base);
|
|
|
|
+ release_mem_region(i2c->twsi_phys, i2c->regsize);
|
|
|
|
+fail_region:
|
|
|
|
+ kfree(i2c);
|
|
|
|
+out:
|
|
|
|
+ return result;
|
|
|
|
+};
|
|
|
|
+
|
|
|
|
+static int __devexit octeon_i2c_remove(struct platform_device *pdev)
|
|
|
|
+{
|
|
|
|
+ struct octeon_i2c *i2c = platform_get_drvdata(pdev);
|
|
|
|
+
|
|
|
|
+ i2c_del_adapter(&i2c->adap);
|
|
|
|
+ platform_set_drvdata(pdev, NULL);
|
|
|
|
+ free_irq(i2c->irq, i2c);
|
|
|
|
+ iounmap(i2c->twsi_base);
|
|
|
|
+ release_mem_region(i2c->twsi_phys, i2c->regsize);
|
|
|
|
+ kfree(i2c);
|
|
|
|
+ return 0;
|
|
|
|
+};
|
|
|
|
+
|
|
|
|
+static struct platform_driver octeon_i2c_driver = {
|
|
|
|
+ .probe = octeon_i2c_probe,
|
|
|
|
+ .remove = __devexit_p(octeon_i2c_remove),
|
|
|
|
+ .driver = {
|
|
|
|
+ .owner = THIS_MODULE,
|
|
|
|
+ .name = DRV_NAME,
|
|
|
|
+ },
|
|
|
|
+};
|
|
|
|
+
|
|
|
|
+static int __init octeon_i2c_init(void)
|
|
|
|
+{
|
|
|
|
+ int rv;
|
|
|
|
+
|
|
|
|
+ rv = platform_driver_register(&octeon_i2c_driver);
|
|
|
|
+ return rv;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static void __exit octeon_i2c_exit(void)
|
|
|
|
+{
|
|
|
|
+ platform_driver_unregister(&octeon_i2c_driver);
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+MODULE_AUTHOR("Michael Lawnick <michael.lawnick.ext@nsn.com>");
|
|
|
|
+MODULE_DESCRIPTION("I2C-Bus adapter for Cavium OCTEON processors");
|
|
|
|
+MODULE_LICENSE("GPL");
|
|
|
|
+MODULE_VERSION(DRV_VERSION);
|
|
|
|
+MODULE_ALIAS("platform:" DRV_NAME);
|
|
|
|
+
|
|
|
|
+module_init(octeon_i2c_init);
|
|
|
|
+module_exit(octeon_i2c_exit);
|