From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Dooks Subject: Re: [PATCH V9] I2C driver for IMX Date: Tue, 15 Jul 2008 17:37:34 +0100 Message-ID: <20080715163734.GK30539@fluff.org.uk> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: i2c-bounces-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org Errors-To: i2c-bounces-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org To: Darius Cc: i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org List-Id: linux-i2c@vger.kernel.org On Fri, Jul 11, 2008 at 09:29:29AM +0300, Darius wrote: > Changes from V8 version: > > - Error numbers replaced to standard numbers from errno.h > - Enable/Start and Disable/Stop functions merged into two Start and Stop functions > - Removed all unused info about slave mode > - Removed unused includes > > Can somebody review functional part of this I2C driver? Because all other part is already acked by ARM Linux kernel guys. > > Signed-off-by: Darius Augulis > --- I'll need a reasonable header/description in place of the changelog before this can be merged. > Index: linux-2.6.26-rc9/arch/arm/mach-imx/mx1ads.c > =================================================================== > --- linux-2.6.26-rc9.orig/arch/arm/mach-imx/mx1ads.c > +++ linux-2.6.26-rc9/arch/arm/mach-imx/mx1ads.c > @@ -109,10 +109,31 @@ static struct platform_device imx_uart2_ > } > }; > > +static struct resource imx_i2c_resources[] = { > + [0] = { > + .start = 0x00217000, > + .end = 0x00217010, > + .flags = IORESOURCE_MEM, > + }, > + [1] = { > + .start = I2C_INT, > + .end = I2C_INT, > + .flags = IORESOURCE_IRQ, > + }, > +}; > + > +static struct platform_device imx_i2c_device = { > + .name = "imx-i2c", > + .id = 0, > + .resource = imx_i2c_resources, > + .num_resources = ARRAY_SIZE(imx_i2c_resources), > +}; > + > static struct platform_device *devices[] __initdata = { > &cs89x0_device, > &imx_uart1_device, > &imx_uart2_device, > + &imx_i2c_device, > }; > > #ifdef CONFIG_MMC_IMX I'm not going to step on RMK's toes unless he gives me explicit acknowledgement to merge arch/arm/mach-imx/mx1ads.c > Index: linux-2.6.26-rc9/drivers/i2c/busses/i2c-imx.c > =================================================================== > --- /dev/null > +++ linux-2.6.26-rc9/drivers/i2c/busses/i2c-imx.c > @@ -0,0 +1,602 @@ > +/* > + * 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 > + * 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 + * Portions: > + * Copyright (C) 2005 Matthias Blaschke + * Copyright (C) 2007 RightHand Technologies, Inc. > + * Copyright (C) 2008 Darius Augulis > + * > + */ > + > +/** Includes ******************************************************************* > +*******************************************************************************/ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +/** 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 int i = 0; > + > + dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); > + > + /* wait for bus not busy */ > + for (i = 0; i < I2C_IMX_TIME_BUSY; i++) { > + if (!(readb(i2c_imx->base + IMX_I2C_I2SR) & (I2SR_IBB | I2SR_IAL))) > + return 0; > + udelay(1); > + } > + dev_dbg(&i2c_imx->adapter.dev, "<%s> I2C bus is busy!\n", __func__); > + return -EBUSY; > +} out of interest, do you really want to be busy-looping here and not allowing the task to sleep? > + > +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; > + } debugging or error messages really shouldn't have ! marks after them. > + 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 int i = 0; > + > + for (i = 0; i < I2C_IMX_TIME_ACK; i++) { > + if (!(readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK)) { > + dev_dbg(&i2c_imx->adapter.dev, > + "<%s> ACK received\n", __func__); > + return 0; > + } > + udelay(1); > + } > + dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK!\n", __func__); > + return -EIO; /* 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); you don't need the () around msgs->addr, or ((msgs->addr)|0x01 writeb( msgs->addr | 0x01, i2c_imx->base + IMX_I2C_I2DR); is acceptable. > + 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)) { again, spaces between items... many of these about. 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)); ^ spaces in here please. > + 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); line is too long. > + 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; why with the () again? > + 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 __devexit 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 = __devexit_p(i2c_imx_remove), > + .driver = { > + .name = DRIVER_NAME, > + .owner = THIS_MODULE, > + } > +}; > + > +static int __init i2c_adap_imx_init(void) > +{ > + return platform_driver_register(&i2c_imx_driver); > +} > + > +static void __exit i2c_adap_imx_exit(void) > +{ > + platform_driver_unregister(&i2c_imx_driver); > + return; > +} > + > +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-rc9/drivers/i2c/busses/Kconfig > =================================================================== > --- linux-2.6.26-rc9.orig/drivers/i2c/busses/Kconfig > +++ linux-2.6.26-rc9/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-rc9/drivers/i2c/busses/Makefile > =================================================================== > --- linux-2.6.26-rc9.orig/drivers/i2c/busses/Makefile > +++ linux-2.6.26-rc9/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 > _______________________________________________ > i2c mailing list > i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org > http://lists.lm-sensors.org/mailman/listinfo/i2c My only comments are: 1) over-use of () where they are not needed 2) you need to insert spaces in expressions. -- Ben (ben-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org, http://www.fluff.org/) 'a smiley only costs 4 bytes' _______________________________________________ i2c mailing list i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org http://lists.lm-sensors.org/mailman/listinfo/i2c