On Fri, Jul 18, 2008 at 09:56:45AM +0300, Darius wrote:
> Description:
>
> Implementation of I2C Adapter/Algorithm Driver
> for I2C Bus integrated in Freescale's i.MXL and i.MX1 processors
>
> Changes from V9 version:
>
> - platform_driver_register replaced by platform_driver_probe because I2C is 
> non-hotpluggable device
> - Patch divided into two separate patches for I2C driver and for board 
> support for I2C device
> - In I2C wait functions dummy cycles replaced by calling shedule();
> - Fixed coding style errors
>
> This driver is not yet compatible with upcomming Clock API for i.MX.
> I'll implement this after 2.6.27-rc1 release.
>
> Signed-off-by: Darius Augulis <[EMAIL PROTECTED]>
> ---

ok, clean up the description and i'll try and include it before
the end of the merge window.

> Index: linux-2.6.26/drivers/i2c/busses/i2c-imx.c
> ===================================================================
> --- /dev/null
> +++ linux-2.6.26/drivers/i2c/busses/i2c-imx.c
> @@ -0,0 +1,617 @@
> +/*
> + *   Copyright (C) 2002 Motorola GSG-China
> + *
> + *   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., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
> + *   USA.
> + *
> + * Author:
> + *   Darius Augulis, Teltonika Inc.
> + *
> + * Desc.:
> + *   Implementation of I2C Adapter/Algorithm Driver
> + *   for I2C Bus integrated in i.MXL, i.MX1
> + *
> + *   module parameters:
> + *           - clkfreq:
> + *                   Sets the desired clock rate
> + *                   The default value is 100000
> + *                   Max value is 400000
> + *
> + *   Derived from Motorola GSG China I2C example driver
> + *
> + *   Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de
> + *   Portions:
> + *   Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de
> + *   Copyright (C) 2007 RightHand Technologies, Inc. 
> <adyeratrighthandtech.com>
> + *   Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt>
> + *
> + */
> +
> +/** Includes 
> *******************************************************************
> +*******************************************************************************/
> +
> +#include <linux/init.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/errno.h>
> +#include <linux/interrupt.h>
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/io.h>
> +#include <linux/sched.h>
> +#include <linux/platform_device.h>
> +#include <asm/arch/irqs.h>
> +#include <asm/arch/hardware.h>
> +#include <asm/arch/imx-regs.h>
> +
> +/** Defines 
> ********************************************************************
> +*******************************************************************************/
> +
> +/* This will be the driver name the kernel reports */
> +#define DRIVER_NAME "imx-i2c"
> +
> +/* Default values of module parameters */
> +#define IMX_I2C_BIT_RATE     100000  /* 100kHz */
> +
> +/* Timeouts */
> +#define I2C_IMX_TIME_BUSY    2000    /* loop count */
> +#define I2C_IMX_TIME_ACK     2000    /* loop count */
> +#define I2C_IMX_TIME_TRX     5       /* seconds */
> +
> +/* IMX I2C registers */
> +#define IMX_I2C_IADR 0x00    /* i2c slave address */
> +#define IMX_I2C_IFDR 0x04    /* i2c frequency divider */
> +#define IMX_I2C_I2CR 0x08    /* i2c control */
> +#define IMX_I2C_I2SR 0x0C    /* i2c status */
> +#define IMX_I2C_I2DR 0x10    /* i2c transfer data */
> +
> +/* Bits of IMX I2C registers */
> +#define I2SR_RXAK    0x01
> +#define I2SR_IIF     0x02
> +#define I2SR_SRW     0x04
> +#define I2SR_IAL     0x10
> +#define I2SR_IBB     0x20
> +#define I2SR_IAAS    0x40
> +#define I2SR_ICF     0x80
> +#define I2CR_RSTA    0x04
> +#define I2CR_TXAK    0x08
> +#define I2CR_MTX     0x10
> +#define I2CR_MSTA    0x20
> +#define I2CR_IIEN    0x40
> +#define I2CR_IEN     0x80
> +
> +/** Variables 
> ******************************************************************
> +*******************************************************************************/
> +
> +static unsigned int clkfreq = IMX_I2C_BIT_RATE;
> +static unsigned int disable_delay;   /* Dummy delay */
> +
> +/*
> + * sorted list of clock divider, register value pairs
> + * taken from table 26-5, p.26-9, Freescale i.MX
> + * Integrated Portable System Processor Reference Manual
> + * Document Number: MC9328MXLRM, Rev. 5.1, 06/2007
> + *
> + * Duplicated divider values removed from list
> + */
> +
> +static u16 __initdata i2c_imx_clk_divider [50] [2] = {
> +     { 22,   0x20 }, { 24,   0x21 }, { 26,   0x22 }, { 28,   0x23 },
> +     { 30,   0x00 }, { 32,   0x24 }, { 36,   0x25 }, { 40,   0x26 },
> +     { 42,   0x03 }, { 44,   0x27 }, { 48,   0x28 }, { 52,   0x05 },
> +     { 56,   0x29 }, { 60,   0x06 }, { 64,   0x2A }, { 72,   0x2B },
> +     { 80,   0x2C }, { 88,   0x09 }, { 96,   0x2D }, { 104,  0x0A },
> +     { 112,  0x2E }, { 128,  0x2F }, { 144,  0x0C }, { 160,  0x30 },
> +     { 192,  0x31 }, { 224,  0x32 }, { 240,  0x0F }, { 256,  0x33 },
> +     { 288,  0x10 }, { 320,  0x34 }, { 384,  0x35 }, { 448,  0x36 },
> +     { 480,  0x13 }, { 512,  0x37 }, { 576,  0x14 }, { 640,  0x38 },
> +     { 768,  0x39 }, { 896,  0x3A }, { 960,  0x17 }, { 1024, 0x3B },
> +     { 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E },
> +     { 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D },
> +     { 3072, 0x1E }, { 3840, 0x1F }
> +};
> +
> +struct imx_i2c_struct {
> +     struct i2c_adapter      adapter;
> +     struct resource         *res;
> +     void __iomem            *base;
> +     int                     irq;
> +     wait_queue_head_t       queue;
> +     unsigned long           i2csr;
> +};
> +
> +/** Functions for IMX I2C adapter driver 
> ***************************************
> +*******************************************************************************/
> +
> +static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx)
> +{
> +     unsigned long orig_jiffies = jiffies;
> +
> +     dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
> +
> +     /* wait for bus not busy */
> +     while (readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_IBB) {
> +             if (signal_pending(current)) {
> +                     dev_dbg(&i2c_imx->adapter.dev,
> +                             "<%s> I2C Interrupted\n", __func__);
> +                     return -EINTR;
> +             }
> +             if (time_after(jiffies, orig_jiffies + HZ)) {
> +                     dev_dbg(&i2c_imx->adapter.dev,
> +                             "<%s> I2C bus is busy\n", __func__);
> +                     return -EIO;
> +             }
> +             schedule();
> +     }
> +
> +     return 0;
> +}
> +
> +static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx)
> +{
> +     int result;
> +
> +     result = wait_event_interruptible_timeout(i2c_imx->queue,
> +             i2c_imx->i2csr & I2SR_IIF, I2C_IMX_TIME_TRX * HZ);
> +
> +     if (unlikely(result < 0)) {
> +             dev_dbg(&i2c_imx->adapter.dev, "<%s> result < 0\n", __func__);
> +             return result;
> +     } else if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
> +             dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
> +             return -ETIMEDOUT;
> +     }
> +     dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__);
> +     i2c_imx->i2csr = 0;
> +     return 0;
> +}
> +
> +static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
> +{
> +     unsigned long orig_jiffies = jiffies;
> +
> +     /* Wait for ack */
> +     while (readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK) {
> +             if (signal_pending(current)) {
> +                     dev_dbg(&i2c_imx->adapter.dev,
> +                             "<%s> I2C Interrupted\n", __func__);
> +                     return -EINTR;
> +             }
> +             if (time_after(jiffies, orig_jiffies + HZ)) {
> +                     dev_dbg(&i2c_imx->adapter.dev,
> +                             "<%s> No ACK\n", __func__);
> +                     return -EIO;
> +             }
> +             schedule();
> +     }
> +
> +     dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__);
> +     return 0;   /* No ACK */
> +}
> +
> +static void i2c_imx_start(struct imx_i2c_struct *i2c_imx)
> +{
> +     unsigned int temp = 0;
> +
> +     dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
> +
> +     /* Enable I2C controller */
> +     writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
> +     /* Start I2C transaction */
> +     temp = readb(i2c_imx->base + IMX_I2C_I2CR);
> +     temp |= I2CR_MSTA;
> +     writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
> +     temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
> +     writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
> +}
> +
> +static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
> +{
> +     unsigned int temp = 0;
> +
> +     /* Stop I2C transaction */
> +     dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
> +     temp = readb(i2c_imx->base + IMX_I2C_I2CR);
> +     temp &= ~I2CR_MSTA;
> +     writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
> +     /* setup chip registers to defaults */
> +     writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
> +     writeb(0, i2c_imx->base + IMX_I2C_I2SR);
> +     /*
> +      * This delay caused by an i.MXL hardware bug.
> +      * If no (or too short) delay, no "STOP" bit will be generated.
> +      */
> +     udelay(disable_delay);
> +     /* Disable I2C controller */
> +     writeb(0, i2c_imx->base + IMX_I2C_I2CR);
> +}
> +
> +static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx, unsigned 
> int rate)
> +{
> +     unsigned int hclk;
> +     unsigned int desired_div;
> +     int i;
> +
> +     /* Divider value calculation */
> +     hclk = imx_get_hclk();
> +     desired_div = (hclk + rate - 1) / rate;
> +     if (desired_div < i2c_imx_clk_divider[0][0])
> +             i = 0;
> +     else if (desired_div > 
> i2c_imx_clk_divider[ARRAY_SIZE(i2c_imx_clk_divider) - 1][0])
> +             i = ARRAY_SIZE(i2c_imx_clk_divider) - 1;
> +     else
> +             for (i = 0; i2c_imx_clk_divider[i][0] < desired_div; i++);
> +
> +     /* Write divider value to register */
> +     writeb(i2c_imx_clk_divider[i][1], i2c_imx->base + IMX_I2C_IFDR);
> +
> +     /*
> +      * There dummy delay is calculated.
> +      * It should be about one I2C clock period long.
> +      * This delay is used in I2C bus disable function
> +      * to fix chip hardware bug.
> +      */
> +     disable_delay = (500000U * i2c_imx_clk_divider[i][0]
> +             + (hclk / 2) - 1) / (hclk / 2);
> +
> +     /* dev_dbg() can't be used, because adapter is not yet registered */
> +#ifdef CONFIG_I2C_DEBUG_BUS
> +     unsigned int sysclk;
> +     sysclk = imx_get_system_clk();
> +     printk(KERN_DEBUG "I2C: <%s> SYSCLK=%d, HCLK=%d, REQ DIV=%d\n",
> +             __func__, sysclk, hclk, desired_div);
> +     printk(KERN_DEBUG "I2C: <%s> IFDR[IC]=0x%x, REAL DIV=%d\n",
> +             __func__, i2c_imx_clk_divider[i][1], i2c_imx_clk_divider[i][0]);
> +#endif
> +}
> +
> +static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
> +{
> +     struct imx_i2c_struct *i2c_imx = dev_id;
> +     unsigned int temp;
> +
> +     temp = readb(i2c_imx->base + IMX_I2C_I2SR);
> +     if (temp & I2SR_IIF) {
> +             /* save status register */
> +             i2c_imx->i2csr = temp;
> +             temp &= ~I2SR_IIF;
> +             writeb(temp, i2c_imx->base + IMX_I2C_I2SR);
> +             wake_up_interruptible(&i2c_imx->queue);
> +     }
> +
> +     return IRQ_HANDLED;
> +}
> +
> +static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg 
> *msgs)
> +{
> +     int i, result;
> +
> +     dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n",
> +             __func__, msgs->addr);
> +
> +     /* write slave address */
> +     writeb(msgs->addr, i2c_imx->base + IMX_I2C_I2DR);
> +     result = i2c_imx_trx_complete(i2c_imx);
> +     if (result)
> +             return result;
> +     result = i2c_imx_acked(i2c_imx);
> +     if (result)
> +             return result;
> +     dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__);
> +
> +     /* write data */
> +     for (i = 0; i < msgs->len; i++) {
> +             dev_dbg(&i2c_imx->adapter.dev,
> +                     "<%s> write byte: B%d=0x%X\n",
> +                     __func__, i, msgs->buf[i]);
> +             writeb(msgs->buf[i], i2c_imx->base + IMX_I2C_I2DR);
> +             result = i2c_imx_trx_complete(i2c_imx);
> +             if (result)
> +                     return result;
> +             result = i2c_imx_acked(i2c_imx);
> +             if (result)
> +                     return result;
> +     }
> +     return 0;
> +}
> +
> +static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
> +{
> +     int i, result;
> +     unsigned int temp;
> +
> +     dev_dbg(&i2c_imx->adapter.dev,
> +             "<%s> write slave address: addr=0x%x\n",
> +             __func__, msgs->addr | 0x01);
> +
> +     /* write slave address */
> +     writeb(msgs->addr | 0x01, i2c_imx->base + IMX_I2C_I2DR);
> +     result = i2c_imx_trx_complete(i2c_imx);
> +     if (result)
> +             return result;
> +     result = i2c_imx_acked(i2c_imx);
> +     if (result)
> +             return result;
> +
> +     dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__);
> +
> +     /* setup bus to read data */
> +     temp = readb(i2c_imx->base + IMX_I2C_I2CR);
> +     temp &= ~I2CR_MTX;
> +     if (msgs->len - 1)
> +             temp &= ~I2CR_TXAK;
> +     writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
> +     readb(i2c_imx->base + IMX_I2C_I2DR); /* dummy read */
> +
> +     dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
> +
> +     /* read data */
> +     for (i = 0; i < msgs->len; i++) {
> +             result = i2c_imx_trx_complete(i2c_imx);
> +             if (result)
> +                     return result;
> +             if (i == (msgs->len - 1)) {
> +                     dev_dbg(&i2c_imx->adapter.dev,
> +                             "<%s> clear MSTA\n", __func__);
> +                     temp = readb(i2c_imx->base + IMX_I2C_I2CR);
> +                     temp &= ~I2CR_MSTA;
> +                     writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
> +             } else if (i == (msgs->len - 2)) {
> +                     dev_dbg(&i2c_imx->adapter.dev,
> +                             "<%s> set TXAK\n", __func__);
> +                     temp = readb(i2c_imx->base + IMX_I2C_I2CR);
> +                     temp |= I2CR_TXAK;
> +                     writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
> +             }
> +             msgs->buf[i] = readb(i2c_imx->base + IMX_I2C_I2DR);
> +             dev_dbg(&i2c_imx->adapter.dev,
> +                     "<%s> read byte: B%d=0x%X\n",
> +                     __func__, i, msgs->buf[i]);
> +     }
> +     return 0;
> +}
> +
> +static int i2c_imx_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, 
> int num)
> +{
> +     unsigned int i, temp;
> +     int result;
> +     struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
> +
> +     dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
> +
> +     /* Check or i2c bus is not busy */
> +     result = i2c_imx_bus_busy(i2c_imx);
> +     if (result)
> +             goto fail0;
> +
> +     /* Start I2C transfer */
> +     i2c_imx_start(i2c_imx);
> +
> +     /* read/write data */
> +     for (i = 0; i < num; i++) {
> +             if (i) {
> +                     dev_dbg(&i2c_imx->adapter.dev,
> +                             "<%s> repeated start\n", __func__);
> +                     temp = readb(i2c_imx->base + IMX_I2C_I2CR);
> +                     temp |= I2CR_RSTA;
> +                     writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
> +             }
> +             dev_dbg(&i2c_imx->adapter.dev,
> +                     "<%s> transfer message: %d\n", __func__, i);
> +             /* write/read data */
> +#ifdef CONFIG_I2C_DEBUG_BUS
> +             temp = readb(i2c_imx->base + IMX_I2C_I2CR);
> +             dev_dbg(&i2c_imx->adapter.dev, "<%s> CONTROL: IEN=%d, IIEN=%d, "
> +                     "MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n", __func__,
> +                     (temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0),
> +                     (temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0),
> +                     (temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0));
> +             temp = readb(i2c_imx->base + IMX_I2C_I2SR);
> +             dev_dbg(&i2c_imx->adapter.dev,
> +                     "<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, "
> +                     "IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n", __func__,
> +                     (temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0),
> +                     (temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0),
> +                     (temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0),
> +                     (temp & I2SR_RXAK ? 1 : 0));
> +#endif
> +             if (msgs[i].flags & I2C_M_RD)
> +                     result = i2c_imx_read(i2c_imx, &msgs[i]);
> +             else
> +                     result = i2c_imx_write(i2c_imx, &msgs[i]);
> +     }
> +
> +fail0:
> +     /* Stop I2C transfer */
> +     i2c_imx_stop(i2c_imx);
> +
> +     dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
> +             (result < 0) ? "error" : "success msg",
> +             (result < 0) ? result : num);
> +     return (result < 0) ? result : num;
> +}
> +
> +static u32 i2c_imx_func(struct i2c_adapter *adapter)
> +{
> +     return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
> +}
> +
> +static struct i2c_algorithm i2c_imx_algo = {
> +     .master_xfer    = i2c_imx_xfer,
> +     .functionality  = i2c_imx_func,
> +};
> +
> +static int __init i2c_imx_probe(struct platform_device *pdev)
> +{
> +     struct imx_i2c_struct *i2c_imx;
> +     struct resource *res;
> +     void __iomem *base;
> +     int irq;
> +     int res_size;
> +     int ret;
> +
> +     dev_dbg(&pdev->dev, "<%s>\n", __func__);
> +
> +     res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +     irq = platform_get_irq(pdev, 0);
> +     if (!res) {
> +             dev_err(&pdev->dev, "can't get device resources\n");
> +             return -ENODEV;
> +     }
> +     if (irq < 0) {
> +             dev_err(&pdev->dev, "can't get irq number\n");
> +             return -ENODEV;
> +     }
> +     res_size = res->end - res->start + 1;
> +     if (!request_mem_region(res->start, res_size, res->name)) {
> +             dev_err(&pdev->dev, "can't allocate %d bytes at %d address\n",
> +                     res_size, res->start);
> +             return -ENOMEM;
> +     }
> +     base = ioremap(res->start, res_size);
> +     if (!base) {
> +             dev_err(&pdev->dev, "ioremap failed\n");
> +             ret = -EIO;
> +             goto fail0;
> +     }
> +     i2c_imx = kzalloc(sizeof(struct imx_i2c_struct), GFP_KERNEL);
> +     if (!i2c_imx) {
> +             dev_err(&pdev->dev, "can't allocate interface\n");
> +             ret = -ENOMEM;
> +             goto fail1;
> +     }
> +
> +     /* Setup i2c_imx driver structure */
> +     strcpy(i2c_imx->adapter.name, pdev->name);
> +     i2c_imx->adapter.owner          = THIS_MODULE;
> +     i2c_imx->adapter.algo           = &i2c_imx_algo;
> +     i2c_imx->adapter.dev.parent     = &pdev->dev;
> +     i2c_imx->adapter.class          = I2C_CLASS_HWMON;
> +     i2c_imx->adapter.nr             = pdev->id;
> +     i2c_imx->irq                    = irq;
> +     i2c_imx->base                   = base;
> +     i2c_imx->res                    = res;
> +
> +     init_waitqueue_head(&i2c_imx->queue);
> +
> +     /* Set up platform driver data */
> +     platform_set_drvdata(pdev, i2c_imx);
> +
> +     ret = request_irq(i2c_imx->irq, i2c_imx_isr,
> +             IRQF_DISABLED, pdev->name, i2c_imx);
> +     if (ret) {
> +             dev_err(&pdev->dev, "cannot claim irq %d\n", i2c_imx->irq);
> +             goto fail2;
> +     }
> +
> +     /* Set up adapter data */
> +     i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
> +
> +     /* Set up clock divider */
> +     i2c_imx_set_clk(i2c_imx, clkfreq);
> +
> +     /* Set up I/O pins for I2C*/
> +     imx_gpio_mode(PA15_PF_I2C_SDA);
> +     imx_gpio_mode(PA16_PF_I2C_SCL);
> +
> +     /* Set up chip registers to defaults */
> +     writeb(0, i2c_imx->base + IMX_I2C_I2CR);
> +     writeb(0, i2c_imx->base + IMX_I2C_I2SR);
> +
> +
> +     /* Add I2C adapter */
> +     ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
> +     if (ret < 0) {
> +             dev_err(&pdev->dev, "registration failed\n");
> +             goto fail3;
> +     }
> +
> +     dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", i2c_imx->irq);
> +     dev_dbg(&i2c_imx->adapter.dev, "device resources from 0x%x to 0x%x\n",
> +             i2c_imx->res->start, i2c_imx->res->end);
> +     dev_dbg(&i2c_imx->adapter.dev, "allocated %d bytes at 0x%x \n",
> +             res_size, i2c_imx->res->start);
> +     dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
> +             i2c_imx->adapter.name);
> +     dev_dbg(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
> +
> +     return 0;   /* Return OK */
> +
> +fail3:
> +     free_irq(i2c_imx->irq, i2c_imx);
> +fail2:
> +     platform_set_drvdata(pdev, NULL);
> +     kfree(i2c_imx);
> +fail1:
> +     iounmap(i2c_imx->base);
> +fail0:
> +     release_mem_region(res->start, res_size);
> +     return ret; /* Return error number */
> +}
> +
> +static int __exit i2c_imx_remove(struct platform_device *pdev)
> +{
> +     struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
> +
> +     /* remove adapter */
> +     dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n");
> +     i2c_del_adapter(&i2c_imx->adapter);
> +     platform_set_drvdata(pdev, NULL);
> +
> +     /* free interrupt */
> +     free_irq(i2c_imx->irq, i2c_imx);
> +
> +     /* setup chip registers to defaults */
> +     writeb(0, i2c_imx->base + IMX_I2C_IADR);
> +     writeb(0, i2c_imx->base + IMX_I2C_IFDR);
> +     writeb(0, i2c_imx->base + IMX_I2C_I2CR);
> +     writeb(0, i2c_imx->base + IMX_I2C_I2SR);
> +
> +     /* release memory */
> +     release_mem_region(i2c_imx->res->start, i2c_imx->res->end - 
> i2c_imx->res->start + 1);
> +     iounmap(i2c_imx->base);
> +     kfree(i2c_imx);
> +     return 0;
> +}
> +
> +static struct platform_driver i2c_imx_driver = {
> +     .probe          = i2c_imx_probe,
> +     .remove         = i2c_imx_remove,
> +     .driver = {
> +             .name   = DRIVER_NAME,
> +             .owner  = THIS_MODULE,
> +     }
> +};
> +
> +static int __init i2c_adap_imx_init(void)
> +{
> +     return platform_driver_probe(&i2c_imx_driver, i2c_imx_probe);
> +}
> +
> +static void __exit i2c_adap_imx_exit(void)
> +{
> +     platform_driver_unregister(&i2c_imx_driver);
> +}
> +
> +module_init(i2c_adap_imx_init);
> +module_exit(i2c_adap_imx_exit);
> +
> +module_param(clkfreq, uint, S_IRUGO);
> +MODULE_PARM_DESC(clkfreq, "desired IMX I2C Clock Rate in Hz");
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Darius Augulis");
> +MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus");
> +MODULE_ALIAS("platform:" DRIVER_NAME);
> Index: linux-2.6.26/drivers/i2c/busses/Kconfig
> ===================================================================
> --- linux-2.6.26.orig/drivers/i2c/busses/Kconfig
> +++ linux-2.6.26/drivers/i2c/busses/Kconfig
> @@ -257,6 +257,16 @@ config I2C_IBM_IIC
>         This driver can also be built as a module.  If so, the module
>         will be called i2c-ibm_iic.
>  
> +config I2C_IMX
> +     tristate "IMX I2C interface"
> +     depends on ARCH_IMX
> +     help
> +       Say Y here if you want to use the IIC bus controller on
> +       the Freescale i.MXL and i.MX1 processors.
> +
> +       This driver can also be built as a module.  If so, the module
> +       will be called i2c-imx.
> +
>  config I2C_IOP3XX
>       tristate "Intel IOPx3xx and IXP4xx on-chip I2C interface"
>       depends on ARCH_IOP32X || ARCH_IOP33X || ARCH_IXP4XX || ARCH_IOP13XX
> Index: linux-2.6.26/drivers/i2c/busses/Makefile
> ===================================================================
> --- linux-2.6.26.orig/drivers/i2c/busses/Makefile
> +++ linux-2.6.26/drivers/i2c/busses/Makefile
> @@ -18,6 +18,7 @@ obj-$(CONFIG_I2C_HYDRA)             += i2c-hydra.o
>  obj-$(CONFIG_I2C_I801)               += i2c-i801.o
>  obj-$(CONFIG_I2C_I810)               += i2c-i810.o
>  obj-$(CONFIG_I2C_IBM_IIC)    += i2c-ibm_iic.o
> +obj-$(CONFIG_I2C_IMX)                += i2c-imx.o
>  obj-$(CONFIG_I2C_IOP3XX)     += i2c-iop3xx.o
>  obj-$(CONFIG_I2C_IXP2000)    += i2c-ixp2000.o
>  obj-$(CONFIG_I2C_POWERMAC)   += i2c-powermac.o

> _______________________________________________
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-- 
Ben ([EMAIL PROTECTED], http://www.fluff.org/)

  'a smiley only costs 4 bytes'

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