[i2c] [PATCH] DaVinci I2C controller support (take#4)

Vladimir Barinov vbarinov at ru.mvista.com
Wed Aug 29 17:05:09 CEST 2007


Hello Jean,

The patch inlined below adds I2C DaVinci controller support after your last review.

> Weird. Can't the firmware be fixed instead?
> Does the locking happens even when not addressing the MSP430? Do you
> have a driver for it? 
I haven't.

I've corrected the places you have pointed to and also I've removed the code related to MSP430 firmware fixes.
We haven't got the TI's response and decided to omit that code. The locking is not reproduceable for other 
devices on i2c bus. I assume that the firmware should certainly be fixed.

The patch is against 2.6.23-rc4 kernel version.

Vladimir

-----------------------
Signed-off-by: Vladimir Barinov <vbarinov at ru.mvista.com>
Acked-by: Trilok Soni <soni.trilok at gmail.com>

Index: linux-2.6.i2c/drivers/i2c/busses/i2c-davinci.c
===================================================================
--- /dev/null
+++ linux-2.6.i2c/drivers/i2c/busses/i2c-davinci.c
@@ -0,0 +1,586 @@
+/*
+ * TI DAVINCI I2C adapter driver.
+ *
+ * Copyright (C) 2006 Texas Instruments.
+ * Copyright (C) 2007 MontaVista Software Inc.
+ *
+ * Updated by Vinod & Sudhakar Feb 2005
+ *
+ * ----------------------------------------------------------------------------
+ *
+ * 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/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/clk.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+
+#include <asm/hardware.h>
+#include <asm/mach-types.h>
+
+#include <asm/arch/i2c.h>
+
+/* ----- global defines ----------------------------------------------- */
+
+#define DAVINCI_I2C_TIMEOUT	(1*HZ)
+#define I2C_DAVINCI_INTR_ALL    (DAVINCI_I2C_IMR_AAS | \
+				 DAVINCI_I2C_IMR_SCD | \
+				 DAVINCI_I2C_IMR_ARDY | \
+				 DAVINCI_I2C_IMR_NACK | \
+				 DAVINCI_I2C_IMR_AL)
+
+#define DAVINCI_I2C_OAR_REG	0x00
+#define DAVINCI_I2C_IMR_REG	0x04
+#define DAVINCI_I2C_STR_REG	0x08
+#define DAVINCI_I2C_CLKL_REG	0x0c
+#define DAVINCI_I2C_CLKH_REG	0x10
+#define DAVINCI_I2C_CNT_REG	0x14
+#define DAVINCI_I2C_DRR_REG	0x18
+#define DAVINCI_I2C_SAR_REG	0x1c
+#define DAVINCI_I2C_DXR_REG	0x20
+#define DAVINCI_I2C_MDR_REG	0x24
+#define DAVINCI_I2C_IVR_REG	0x28
+#define DAVINCI_I2C_EMDR_REG	0x2c
+#define DAVINCI_I2C_PSC_REG	0x30
+
+#define DAVINCI_I2C_IVR_AAS	0x07
+#define DAVINCI_I2C_IVR_SCD	0x06
+#define DAVINCI_I2C_IVR_XRDY	0x05
+#define DAVINCI_I2C_IVR_RDR	0x04
+#define DAVINCI_I2C_IVR_ARDY	0x03
+#define DAVINCI_I2C_IVR_NACK	0x02
+#define DAVINCI_I2C_IVR_AL	0x01
+
+#define DAVINCI_I2C_STR_BB	(1 << 12)
+#define DAVINCI_I2C_STR_RSFULL	(1 << 11)
+#define DAVINCI_I2C_STR_SCD	(1 << 5)
+#define DAVINCI_I2C_STR_ARDY	(1 << 2)
+#define DAVINCI_I2C_STR_NACK	(1 << 1)
+#define DAVINCI_I2C_STR_AL	(1 << 0)
+
+#define DAVINCI_I2C_MDR_NACK	(1 << 15)
+#define DAVINCI_I2C_MDR_STT	(1 << 13)
+#define DAVINCI_I2C_MDR_STP	(1 << 11)
+#define DAVINCI_I2C_MDR_MST	(1 << 10)
+#define DAVINCI_I2C_MDR_TRX	(1 << 9)
+#define DAVINCI_I2C_MDR_XA	(1 << 8)
+#define DAVINCI_I2C_MDR_IRS	(1 << 5)
+
+#define DAVINCI_I2C_IMR_AAS	(1 << 6)
+#define DAVINCI_I2C_IMR_SCD	(1 << 5)
+#define DAVINCI_I2C_IMR_XRDY	(1 << 4)
+#define DAVINCI_I2C_IMR_RRDY	(1 << 3)
+#define DAVINCI_I2C_IMR_ARDY	(1 << 2)
+#define DAVINCI_I2C_IMR_NACK	(1 << 1)
+#define DAVINCI_I2C_IMR_AL	(1 << 0)
+
+#define MOD_REG_BIT(val, mask, set) do { \
+	if (set) { \
+		val |= mask; \
+	} else { \
+		val &= ~mask; \
+	} \
+} while (0)
+
+struct davinci_i2c_dev {
+	struct device           *dev;
+	void __iomem		*base;
+	struct completion	cmd_complete;
+	struct clk              *clk;
+	int			cmd_err;
+	u8			*buf;
+	size_t			buf_len;
+	int			irq;
+	struct i2c_adapter	adapter;
+};
+
+/* default platform data to use if not supplied in the platform_device */
+static struct davinci_i2c_platform_data davinci_i2c_platform_data_default = {
+	.bus_freq	= 100,
+	.bus_delay	= 0,
+};
+
+static inline void davinci_i2c_write_reg(struct davinci_i2c_dev *i2c_dev,
+					 int reg, u16 val)
+{
+	__raw_writew(val, i2c_dev->base + reg);
+}
+
+static inline u16 davinci_i2c_read_reg(struct davinci_i2c_dev *i2c_dev, int reg)
+{
+	return __raw_readw(i2c_dev->base + reg);
+}
+
+/*
+ * This functions configures I2C and brings I2C out of reset.
+ * This function is called during I2C init function. This function
+ * also gets called if I2C encounters any errors.
+ */
+static int i2c_davinci_init(struct davinci_i2c_dev *dev)
+{
+	struct davinci_i2c_platform_data *pdata = dev->dev->platform_data;
+	u16 psc;
+	u32 clk;
+	u32 clkh;
+	u32 clkl;
+	u32 input_clock = clk_get_rate(dev->clk);
+	u16 w;
+
+	if (!pdata)
+		pdata = &davinci_i2c_platform_data_default;
+
+	/* put I2C into reset */
+	w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
+	MOD_REG_BIT(w, DAVINCI_I2C_MDR_IRS, 0);
+	davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w);
+
+	/* NOTE: I2C Clock divider programming info
+	 * As per I2C specs the following formulas provide prescaler
+	 * and low/high divider values
+	 * input clk --> PSC Div -----------> ICCL/H Div --> output clock
+	 *                       module clk
+	 *
+	 * output clk = module clk / (PSC + 1) [ (ICCL + d) + (ICCH + d) ]
+	 *
+	 * Thus,
+	 * (ICCL + ICCH) = clk = (input clk / ((psc +1) * output clk)) - 2d;
+	 *
+	 * where if PSC == 0, d = 7,
+	 *       if PSC == 1, d = 6
+	 *       if PSC > 1 , d = 5
+	 */
+
+	psc = 26; /* To get 1MHz clock */
+
+	clk = ((input_clock / (psc + 1)) / (pdata->bus_freq * 1000)) - 10;
+	clkh = (50 * clk) / 100;
+	clkl = clk - clkh;
+
+	davinci_i2c_write_reg(dev, DAVINCI_I2C_PSC_REG, psc);
+	davinci_i2c_write_reg(dev, DAVINCI_I2C_CLKH_REG, clkh);
+	davinci_i2c_write_reg(dev, DAVINCI_I2C_CLKL_REG, clkl);
+
+	dev_dbg(dev->dev, "CLK  = %d\n", clk);
+	dev_dbg(dev->dev, "PSC  = %d\n",
+		davinci_i2c_read_reg(dev, DAVINCI_I2C_PSC_REG));
+	dev_dbg(dev->dev, "CLKL = %d\n",
+		davinci_i2c_read_reg(dev, DAVINCI_I2C_CLKL_REG));
+	dev_dbg(dev->dev, "CLKH = %d\n",
+		davinci_i2c_read_reg(dev, DAVINCI_I2C_CLKH_REG));
+
+	/* Take the I2C module out of reset: */
+	w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
+	MOD_REG_BIT(w, DAVINCI_I2C_MDR_IRS, 1);
+	davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w);
+
+	/* Enable interrupts */
+	davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, I2C_DAVINCI_INTR_ALL);
+
+	return 0;
+}
+
+/*
+ * Waiting for bus not busy
+ */
+static int i2c_davinci_wait_bus_not_busy(struct davinci_i2c_dev *dev,
+					 char allow_sleep)
+{
+	unsigned long timeout;
+
+	timeout = jiffies + DAVINCI_I2C_TIMEOUT;
+	while (davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG)
+	       & DAVINCI_I2C_STR_BB) {
+		if (time_after(jiffies, timeout)) {
+			dev_warn(dev->dev,
+				 "timeout waiting for bus ready\n");
+			return -ETIMEDOUT;
+		}
+		if (allow_sleep)
+			schedule_timeout(1);
+	}
+
+	return 0;
+}
+
+/*
+ * Low level master read/write transaction. This function is called
+ * from i2c_davinci_xfer.
+ */
+static int
+i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop)
+{
+	struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+	struct davinci_i2c_platform_data *pdata = dev->dev->platform_data;
+	u32 flag;
+	u32 stat;
+	u16 w;
+	int r;
+
+	if (msg->len == 0)
+		return -EINVAL;
+
+	if (!pdata)
+		pdata = &davinci_i2c_platform_data_default;
+	/* Introduce a delay, required for some boards (e.g Davinci EVM) */
+	if (pdata->bus_delay)
+		udelay(pdata->bus_delay);
+
+	/* set the slave address */
+	davinci_i2c_write_reg(dev, DAVINCI_I2C_SAR_REG, msg->addr);
+
+	dev->buf = msg->buf;
+	dev->buf_len = msg->len;
+
+	davinci_i2c_write_reg(dev, DAVINCI_I2C_CNT_REG, dev->buf_len);
+
+	init_completion(&dev->cmd_complete);
+	dev->cmd_err = 0;
+
+	/* Clear any pending interrupts by reading the IVR */
+	stat = davinci_i2c_read_reg(dev, DAVINCI_I2C_IVR_REG);
+
+	/* Take I2C out of reset, configure it as master and set the
+	 * start bit */
+	flag = DAVINCI_I2C_MDR_IRS | DAVINCI_I2C_MDR_MST | DAVINCI_I2C_MDR_STT;
+
+	/* if the slave address is ten bit address, enable XA bit */
+	if (msg->flags & I2C_M_TEN)
+		flag |= DAVINCI_I2C_MDR_XA;
+	if (!(msg->flags & I2C_M_RD))
+		flag |= DAVINCI_I2C_MDR_TRX;
+	if (stop)
+		flag |= DAVINCI_I2C_MDR_STP;
+
+	/* Enable receive or transmit interrupts */
+	w = davinci_i2c_read_reg(dev, DAVINCI_I2C_IMR_REG);
+	if (msg->flags & I2C_M_RD)
+		MOD_REG_BIT(w, DAVINCI_I2C_IMR_RRDY, 1);
+	else
+		MOD_REG_BIT(w, DAVINCI_I2C_IMR_XRDY, 1);
+	davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, w);
+
+	/* write the data into mode register */
+	davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag);
+
+	r = wait_for_completion_interruptible_timeout(&dev->cmd_complete,
+						      DAVINCI_I2C_TIMEOUT);
+	dev->buf_len = 0;
+	if (r < 0)
+		return r;
+
+	if (r == 0) {
+		dev_err(dev->dev, "controller timed out\n");
+		i2c_davinci_init(dev);
+		return -ETIMEDOUT;
+	}
+
+	/* no error */
+	if (likely(!dev->cmd_err))
+		return msg->len;
+
+	/* We have an error */
+	if (dev->cmd_err & DAVINCI_I2C_STR_AL) {
+		i2c_davinci_init(dev);
+		return -EIO;
+	}
+
+	if (dev->cmd_err & DAVINCI_I2C_STR_NACK) {
+		if (msg->flags & I2C_M_IGNORE_NAK)
+			return msg->len;
+		if (stop) {
+			w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
+			MOD_REG_BIT(w, DAVINCI_I2C_MDR_STP, 1);
+			davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w);
+		}
+		return -EREMOTEIO;
+	}
+	return -EIO;
+}
+
+/*
+ * Prepare controller for a transaction and call i2c_davinci_xfer_msg
+ */
+static int
+i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
+{
+	struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+	int i;
+	int ret;
+
+	dev_dbg(dev->dev, "%s: msgs: %d\n", __FUNCTION__, num);
+
+	ret = i2c_davinci_wait_bus_not_busy(dev, 1);
+	if (ret < 0) {
+		dev_warn(dev->dev, "timeout waiting for bus ready\n");
+		return ret;
+	}
+
+	for (i = 0; i < num; i++) {
+		ret = i2c_davinci_xfer_msg(adap, &msgs[i], (i == (num - 1)));
+		if (ret < 0)
+			return ret;
+	}
+
+	dev_dbg(dev->dev, "%s:%d ret: %d\n", __FUNCTION__, __LINE__, ret);
+
+	return num;
+}
+
+static u32 i2c_davinci_func(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+}
+
+/*
+ * Interrupt service routine. This gets called whenever an I2C interrupt
+ * occurs.
+ */
+static irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id)
+{
+	struct davinci_i2c_dev *dev = dev_id;
+	u32 stat;
+	int count = 0;
+	u16 w;
+
+	while ((stat = davinci_i2c_read_reg(dev, DAVINCI_I2C_IVR_REG))) {
+		dev_dbg(dev->dev, "%s: stat=0x%x\n", __FUNCTION__, stat);
+		if (count++ == 100) {
+			dev_warn(dev->dev, "Too much work in one IRQ\n");
+			break;
+		}
+
+		switch (stat) {
+		case DAVINCI_I2C_IVR_AL:
+			dev->cmd_err |= DAVINCI_I2C_STR_AL;
+			complete(&dev->cmd_complete);
+			break;
+
+		case DAVINCI_I2C_IVR_NACK:
+			dev->cmd_err |= DAVINCI_I2C_STR_NACK;
+			complete(&dev->cmd_complete);
+			break;
+
+		case DAVINCI_I2C_IVR_ARDY:
+			w = davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG);
+			MOD_REG_BIT(w, DAVINCI_I2C_STR_ARDY, 1);
+			davinci_i2c_write_reg(dev, DAVINCI_I2C_STR_REG, w);
+			complete(&dev->cmd_complete);
+			break;
+
+		case DAVINCI_I2C_IVR_RDR:
+			if (dev->buf_len) {
+				*dev->buf++ =
+				    davinci_i2c_read_reg(dev,
+							 DAVINCI_I2C_DRR_REG);
+				dev->buf_len--;
+				if (dev->buf_len)
+					continue;
+
+				w = davinci_i2c_read_reg(dev,
+							 DAVINCI_I2C_STR_REG);
+				MOD_REG_BIT(w, DAVINCI_I2C_IMR_RRDY, 0);
+				davinci_i2c_write_reg(dev,
+						      DAVINCI_I2C_STR_REG,
+						      w);
+			} else
+				dev_err(dev->dev, "RDR IRQ while no"
+					"data requested\n");
+			break;
+
+		case DAVINCI_I2C_IVR_XRDY:
+			if (dev->buf_len) {
+				davinci_i2c_write_reg(dev, DAVINCI_I2C_DXR_REG,
+						      *dev->buf++);
+				dev->buf_len--;
+				if (dev->buf_len)
+					continue;
+
+				w = davinci_i2c_read_reg(dev,
+							 DAVINCI_I2C_IMR_REG);
+				MOD_REG_BIT(w, DAVINCI_I2C_IMR_XRDY, 0);
+				davinci_i2c_write_reg(dev,
+						      DAVINCI_I2C_IMR_REG,
+						      w);
+			} else
+				dev_err(dev->dev, "TDR IRQ while no data to"
+					"send\n");
+			break;
+
+		case DAVINCI_I2C_IVR_SCD:
+			w = davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG);
+			MOD_REG_BIT(w, DAVINCI_I2C_STR_SCD, 1);
+			davinci_i2c_write_reg(dev, DAVINCI_I2C_STR_REG, w);
+			complete(&dev->cmd_complete);
+			break;
+
+		case DAVINCI_I2C_IVR_AAS:
+			dev_warn(dev->dev, "Address as slave interrupt\n");
+		}/* switch */
+	}/* while */
+
+	return count ? IRQ_HANDLED : IRQ_NONE;
+}
+
+static struct i2c_algorithm i2c_davinci_algo = {
+	.master_xfer	= i2c_davinci_xfer,
+	.functionality	= i2c_davinci_func,
+};
+
+static int davinci_i2c_probe(struct platform_device *pdev)
+{
+	struct davinci_i2c_dev *dev;
+	struct i2c_adapter *adap;
+	struct resource *mem, *irq, *ioarea;
+	int r;
+
+	/* NOTE: driver uses the static register mapping */
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem) {
+		dev_err(&pdev->dev, "no mem resource?\n");
+		return -ENODEV;
+	}
+
+	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!irq) {
+		dev_err(&pdev->dev, "no irq resource?\n");
+		return -ENODEV;
+	}
+
+	ioarea = request_mem_region(mem->start, (mem->end - mem->start) + 1,
+				    pdev->name);
+	if (!ioarea) {
+		dev_err(&pdev->dev, "I2C region already claimed\n");
+		return -EBUSY;
+	}
+
+	dev = kzalloc(sizeof(struct davinci_i2c_dev), GFP_KERNEL);
+	if (!dev) {
+		r = -ENOMEM;
+		goto err_release_region;
+	}
+
+	dev->dev = get_device(&pdev->dev);
+	dev->irq = irq->start;
+	platform_set_drvdata(pdev, dev);
+
+	dev->clk = clk_get(&pdev->dev, "I2CCLK");
+	if (IS_ERR(dev->clk)) {
+		r = -ENODEV;
+		goto err_free_mem;
+	}
+	clk_enable(dev->clk);
+
+	dev->base = (void __iomem *)IO_ADDRESS(mem->start);
+	i2c_davinci_init(dev);
+
+	r = request_irq(dev->irq, i2c_davinci_isr, 0, pdev->name, dev);
+	if (r) {
+		dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
+		goto err_unuse_clocks;
+	}
+
+	adap = &dev->adapter;
+	i2c_set_adapdata(adap, dev);
+	adap->owner = THIS_MODULE;
+	adap->class = I2C_CLASS_HWMON;
+	strlcpy(adap->name, "DaVinci I2C adapter", sizeof(adap->name));
+	adap->algo = &i2c_davinci_algo;
+	adap->dev.parent = &pdev->dev;
+
+	/* FIXME */
+	adap->timeout = 1;
+	adap->retries = 1;
+
+	adap->nr = pdev->id;
+	r = i2c_add_numbered_adapter(adap);
+	if (r) {
+		dev_err(&pdev->dev, "failure adding adapter\n");
+		goto err_free_irq;
+	}
+
+	return 0;
+
+err_free_irq:
+	free_irq(dev->irq, dev);
+err_unuse_clocks:
+	clk_disable(dev->clk);
+	clk_put(dev->clk);
+	dev->clk = NULL;
+err_free_mem:
+	platform_set_drvdata(pdev, NULL);
+	put_device(&pdev->dev);
+	kfree(dev);
+err_release_region:
+	release_mem_region(mem->start, (mem->end - mem->start) + 1);
+
+	return r;
+}
+
+static int davinci_i2c_remove(struct platform_device *pdev)
+{
+	struct davinci_i2c_dev *dev = platform_get_drvdata(pdev);
+	struct resource *mem;
+
+	platform_set_drvdata(pdev, NULL);
+	i2c_del_adapter(&dev->adapter);
+	put_device(&pdev->dev);
+
+	clk_disable(dev->clk);
+	clk_put(dev->clk);
+	dev->clk = NULL;
+
+	davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, 0);
+	free_irq(IRQ_I2C, dev);
+	kfree(dev);
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	release_mem_region(mem->start, (mem->end - mem->start) + 1);
+	return 0;
+}
+
+static struct platform_driver davinci_i2c_driver = {
+	.probe		= davinci_i2c_probe,
+	.remove		= davinci_i2c_remove,
+	.driver		= {
+		.name	= "i2c_davinci",
+		.owner	= THIS_MODULE,
+	},
+};
+
+/* I2C may be needed to bring up other drivers */
+static int __init davinci_i2c_init_driver(void)
+{
+	return platform_driver_register(&davinci_i2c_driver);
+}
+subsys_initcall(davinci_i2c_init_driver);
+
+static void __exit davinci_i2c_exit_driver(void)
+{
+	platform_driver_unregister(&davinci_i2c_driver);
+}
+module_exit(davinci_i2c_exit_driver);
+
+MODULE_AUTHOR("Texas Instruments India");
+MODULE_DESCRIPTION("TI DaVinci I2C bus adapter");
+MODULE_LICENSE("GPL");
Index: linux-2.6.i2c/drivers/i2c/busses/Kconfig
===================================================================
--- linux-2.6.i2c.orig/drivers/i2c/busses/Kconfig
+++ linux-2.6.i2c/drivers/i2c/busses/Kconfig
@@ -106,6 +106,19 @@ config I2C_BLACKFIN_TWI_CLK_KHZ
 	help
 	  The unit of the TWI clock is kHz.
 
+config I2C_DAVINCI
+	tristate "DaVinci I2C driver"
+	depends on ARCH_DAVINCI
+	help
+	  Support for TI DaVinci I2C controller driver.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c-davinci.
+
+	  Please note that this driver might be needed to bring up other
+	  devices such as DaVinci NIC.
+	  For details please see http://www.ti.com/davinci
+
 config I2C_ELEKTOR
 	tristate "Elektor ISA card"
 	depends on ISA && BROKEN_ON_SMP
Index: linux-2.6.i2c/drivers/i2c/busses/Makefile
===================================================================
--- linux-2.6.i2c.orig/drivers/i2c/busses/Makefile
+++ linux-2.6.i2c/drivers/i2c/busses/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_I2C_AMD8111)	+= i2c-amd8111
 obj-$(CONFIG_I2C_AT91)		+= i2c-at91.o
 obj-$(CONFIG_I2C_AU1550)	+= i2c-au1550.o
 obj-$(CONFIG_I2C_BLACKFIN_TWI)	+= i2c-bfin-twi.o
+obj-$(CONFIG_I2C_DAVINCI)	+= i2c-davinci.o
 obj-$(CONFIG_I2C_ELEKTOR)	+= i2c-elektor.o
 obj-$(CONFIG_I2C_GPIO)		+= i2c-gpio.o
 obj-$(CONFIG_I2C_HYDRA)		+= i2c-hydra.o
Index: linux-2.6.i2c/include/asm-arm/arch-davinci/i2c.h
===================================================================
--- /dev/null
+++ linux-2.6.i2c/include/asm-arm/arch-davinci/i2c.h
@@ -0,0 +1,21 @@
+/*
+ * DaVinci I2C controller platfrom_device info
+ *
+ * Author: Vladimir Barinov, MontaVista Software, Inc. <source at mvista.com>
+ *
+ * 2007 (c) MontaVista Software, Inc. This file is licensed under
+ * the terms of the GNU General Public License version 2. This program
+ * is licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+*/
+
+#ifndef __ASM_ARCH_I2C_H
+#define __ASM_ARCH_I2C_H
+
+/* All frequencies are expressed in kHz */
+struct davinci_i2c_platform_data {
+	unsigned int	bus_freq;	/* standard bus frequency */
+	unsigned int	bus_delay;	/* transaction delay */
+};
+
+#endif /* __ASM_ARCH_I2C_H */



More information about the i2c mailing list