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![Marc Kleine-Budde](/assets/img/avatar_default.png)
The i2c_imx_trx_complete() function is using wait_event_interruptible_timeout() to wait for the I2C controller to signal that it has completed an I2C bus operation. If the process that causes the I2C operation receives a signal, the wait will be interrupted, returning an error. It is better to let the I2C operation finished before handling the signal (i.e. returning into userspace). It is safe to use wait_event_timeout() instead, because the timeout will allow the process to exit if the I2C bus hangs. It's also better to allow the I2C operation to finish, because unacknowledged I2C operations can cause the I2C bus to hang. Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Reviewed-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
649 lines
18 KiB
C
649 lines
18 KiB
C
/*
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* Copyright (C) 2002 Motorola GSG-China
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
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* USA.
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*
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* Author:
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* Darius Augulis, Teltonika Inc.
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*
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* Desc.:
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* Implementation of I2C Adapter/Algorithm Driver
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* for I2C Bus integrated in Freescale i.MX/MXC processors
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*
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* Derived from Motorola GSG China I2C example driver
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*
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* Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de
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* Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de
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* Copyright (C) 2007 RightHand Technologies, Inc.
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* Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt>
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*
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*/
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/** Includes *******************************************************************
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*******************************************************************************/
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/errno.h>
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#include <linux/err.h>
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#include <linux/interrupt.h>
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#include <linux/delay.h>
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#include <linux/i2c.h>
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#include <linux/io.h>
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#include <linux/sched.h>
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#include <linux/platform_device.h>
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#include <linux/clk.h>
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#include <linux/slab.h>
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#include <mach/irqs.h>
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#include <mach/hardware.h>
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#include <mach/i2c.h>
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/** Defines ********************************************************************
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*******************************************************************************/
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/* This will be the driver name the kernel reports */
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#define DRIVER_NAME "imx-i2c"
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/* Default value */
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#define IMX_I2C_BIT_RATE 100000 /* 100kHz */
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/* IMX I2C registers */
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#define IMX_I2C_IADR 0x00 /* i2c slave address */
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#define IMX_I2C_IFDR 0x04 /* i2c frequency divider */
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#define IMX_I2C_I2CR 0x08 /* i2c control */
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#define IMX_I2C_I2SR 0x0C /* i2c status */
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#define IMX_I2C_I2DR 0x10 /* i2c transfer data */
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/* Bits of IMX I2C registers */
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#define I2SR_RXAK 0x01
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#define I2SR_IIF 0x02
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#define I2SR_SRW 0x04
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#define I2SR_IAL 0x10
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#define I2SR_IBB 0x20
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#define I2SR_IAAS 0x40
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#define I2SR_ICF 0x80
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#define I2CR_RSTA 0x04
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#define I2CR_TXAK 0x08
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#define I2CR_MTX 0x10
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#define I2CR_MSTA 0x20
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#define I2CR_IIEN 0x40
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#define I2CR_IEN 0x80
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/** Variables ******************************************************************
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*******************************************************************************/
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/*
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* sorted list of clock divider, register value pairs
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* taken from table 26-5, p.26-9, Freescale i.MX
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* Integrated Portable System Processor Reference Manual
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* Document Number: MC9328MXLRM, Rev. 5.1, 06/2007
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*
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* Duplicated divider values removed from list
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*/
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static u16 __initdata i2c_clk_div[50][2] = {
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{ 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 },
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{ 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 },
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{ 42, 0x03 }, { 44, 0x27 }, { 48, 0x28 }, { 52, 0x05 },
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{ 56, 0x29 }, { 60, 0x06 }, { 64, 0x2A }, { 72, 0x2B },
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{ 80, 0x2C }, { 88, 0x09 }, { 96, 0x2D }, { 104, 0x0A },
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{ 112, 0x2E }, { 128, 0x2F }, { 144, 0x0C }, { 160, 0x30 },
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{ 192, 0x31 }, { 224, 0x32 }, { 240, 0x0F }, { 256, 0x33 },
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{ 288, 0x10 }, { 320, 0x34 }, { 384, 0x35 }, { 448, 0x36 },
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{ 480, 0x13 }, { 512, 0x37 }, { 576, 0x14 }, { 640, 0x38 },
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{ 768, 0x39 }, { 896, 0x3A }, { 960, 0x17 }, { 1024, 0x3B },
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{ 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E },
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{ 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D },
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{ 3072, 0x1E }, { 3840, 0x1F }
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};
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struct imx_i2c_struct {
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struct i2c_adapter adapter;
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struct resource *res;
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struct clk *clk;
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void __iomem *base;
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int irq;
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wait_queue_head_t queue;
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unsigned long i2csr;
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unsigned int disable_delay;
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int stopped;
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unsigned int ifdr; /* IMX_I2C_IFDR */
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};
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/** Functions for IMX I2C adapter driver ***************************************
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*******************************************************************************/
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static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
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{
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unsigned long orig_jiffies = jiffies;
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unsigned int temp;
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dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
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while (1) {
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temp = readb(i2c_imx->base + IMX_I2C_I2SR);
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if (for_busy && (temp & I2SR_IBB))
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break;
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if (!for_busy && !(temp & I2SR_IBB))
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break;
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if (signal_pending(current)) {
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dev_dbg(&i2c_imx->adapter.dev,
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"<%s> I2C Interrupted\n", __func__);
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return -EINTR;
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}
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if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
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dev_dbg(&i2c_imx->adapter.dev,
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"<%s> I2C bus is busy\n", __func__);
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return -ETIMEDOUT;
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}
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schedule();
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}
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return 0;
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}
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static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx)
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{
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wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
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if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
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dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
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return -ETIMEDOUT;
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}
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dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__);
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i2c_imx->i2csr = 0;
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return 0;
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}
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static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
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{
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if (readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK) {
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dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
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return -EIO; /* No ACK */
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}
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dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__);
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return 0;
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}
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static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
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{
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unsigned int temp = 0;
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int result;
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dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
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clk_enable(i2c_imx->clk);
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writeb(i2c_imx->ifdr, i2c_imx->base + IMX_I2C_IFDR);
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/* Enable I2C controller */
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writeb(0, i2c_imx->base + IMX_I2C_I2SR);
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writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
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/* Wait controller to be stable */
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udelay(50);
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/* Start I2C transaction */
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temp = readb(i2c_imx->base + IMX_I2C_I2CR);
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temp |= I2CR_MSTA;
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writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
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result = i2c_imx_bus_busy(i2c_imx, 1);
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if (result)
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return result;
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i2c_imx->stopped = 0;
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temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
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writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
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return result;
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}
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static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
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{
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unsigned int temp = 0;
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if (!i2c_imx->stopped) {
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/* Stop I2C transaction */
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dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
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temp = readb(i2c_imx->base + IMX_I2C_I2CR);
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temp &= ~(I2CR_MSTA | I2CR_MTX);
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writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
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}
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if (cpu_is_mx1()) {
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/*
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* This delay caused by an i.MXL hardware bug.
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* If no (or too short) delay, no "STOP" bit will be generated.
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*/
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udelay(i2c_imx->disable_delay);
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}
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if (!i2c_imx->stopped) {
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i2c_imx_bus_busy(i2c_imx, 0);
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i2c_imx->stopped = 1;
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}
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/* Disable I2C controller */
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writeb(0, i2c_imx->base + IMX_I2C_I2CR);
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clk_disable(i2c_imx->clk);
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}
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static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
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unsigned int rate)
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{
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unsigned int i2c_clk_rate;
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unsigned int div;
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int i;
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/* Divider value calculation */
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i2c_clk_rate = clk_get_rate(i2c_imx->clk);
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div = (i2c_clk_rate + rate - 1) / rate;
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if (div < i2c_clk_div[0][0])
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i = 0;
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else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0])
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i = ARRAY_SIZE(i2c_clk_div) - 1;
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else
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for (i = 0; i2c_clk_div[i][0] < div; i++);
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/* Store divider value */
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i2c_imx->ifdr = i2c_clk_div[i][1];
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/*
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* There dummy delay is calculated.
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* It should be about one I2C clock period long.
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* This delay is used in I2C bus disable function
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* to fix chip hardware bug.
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*/
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i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0]
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+ (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2);
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/* dev_dbg() can't be used, because adapter is not yet registered */
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#ifdef CONFIG_I2C_DEBUG_BUS
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printk(KERN_DEBUG "I2C: <%s> I2C_CLK=%d, REQ DIV=%d\n",
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__func__, i2c_clk_rate, div);
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printk(KERN_DEBUG "I2C: <%s> IFDR[IC]=0x%x, REAL DIV=%d\n",
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__func__, i2c_clk_div[i][1], i2c_clk_div[i][0]);
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#endif
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}
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static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
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{
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struct imx_i2c_struct *i2c_imx = dev_id;
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unsigned int temp;
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temp = readb(i2c_imx->base + IMX_I2C_I2SR);
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if (temp & I2SR_IIF) {
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/* save status register */
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i2c_imx->i2csr = temp;
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temp &= ~I2SR_IIF;
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writeb(temp, i2c_imx->base + IMX_I2C_I2SR);
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wake_up(&i2c_imx->queue);
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return IRQ_HANDLED;
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}
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return IRQ_NONE;
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}
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static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
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{
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int i, result;
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dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n",
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__func__, msgs->addr << 1);
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/* write slave address */
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writeb(msgs->addr << 1, i2c_imx->base + IMX_I2C_I2DR);
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result = i2c_imx_trx_complete(i2c_imx);
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if (result)
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return result;
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result = i2c_imx_acked(i2c_imx);
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if (result)
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return result;
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dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__);
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/* write data */
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for (i = 0; i < msgs->len; i++) {
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dev_dbg(&i2c_imx->adapter.dev,
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"<%s> write byte: B%d=0x%X\n",
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__func__, i, msgs->buf[i]);
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writeb(msgs->buf[i], i2c_imx->base + IMX_I2C_I2DR);
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result = i2c_imx_trx_complete(i2c_imx);
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if (result)
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return result;
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result = i2c_imx_acked(i2c_imx);
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if (result)
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return result;
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}
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return 0;
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}
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static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
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{
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int i, result;
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unsigned int temp;
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dev_dbg(&i2c_imx->adapter.dev,
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"<%s> write slave address: addr=0x%x\n",
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__func__, (msgs->addr << 1) | 0x01);
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/* write slave address */
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writeb((msgs->addr << 1) | 0x01, i2c_imx->base + IMX_I2C_I2DR);
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result = i2c_imx_trx_complete(i2c_imx);
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if (result)
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return result;
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result = i2c_imx_acked(i2c_imx);
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if (result)
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return result;
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dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__);
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/* setup bus to read data */
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temp = readb(i2c_imx->base + IMX_I2C_I2CR);
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temp &= ~I2CR_MTX;
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if (msgs->len - 1)
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temp &= ~I2CR_TXAK;
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writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
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readb(i2c_imx->base + IMX_I2C_I2DR); /* dummy read */
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dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
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/* read data */
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for (i = 0; i < msgs->len; i++) {
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result = i2c_imx_trx_complete(i2c_imx);
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if (result)
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return result;
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if (i == (msgs->len - 1)) {
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/* It must generate STOP before read I2DR to prevent
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controller from generating another clock cycle */
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dev_dbg(&i2c_imx->adapter.dev,
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"<%s> clear MSTA\n", __func__);
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temp = readb(i2c_imx->base + IMX_I2C_I2CR);
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temp &= ~(I2CR_MSTA | I2CR_MTX);
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writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
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i2c_imx_bus_busy(i2c_imx, 0);
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i2c_imx->stopped = 1;
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} else if (i == (msgs->len - 2)) {
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dev_dbg(&i2c_imx->adapter.dev,
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"<%s> set TXAK\n", __func__);
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temp = readb(i2c_imx->base + IMX_I2C_I2CR);
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temp |= I2CR_TXAK;
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writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
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}
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msgs->buf[i] = readb(i2c_imx->base + IMX_I2C_I2DR);
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dev_dbg(&i2c_imx->adapter.dev,
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"<%s> read byte: B%d=0x%X\n",
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__func__, i, msgs->buf[i]);
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}
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return 0;
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}
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static int i2c_imx_xfer(struct i2c_adapter *adapter,
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struct i2c_msg *msgs, int num)
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{
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unsigned int i, temp;
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int result;
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struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
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dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
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/* Start I2C transfer */
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result = i2c_imx_start(i2c_imx);
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if (result)
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goto fail0;
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/* read/write data */
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for (i = 0; i < num; i++) {
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if (i) {
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dev_dbg(&i2c_imx->adapter.dev,
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"<%s> repeated start\n", __func__);
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temp = readb(i2c_imx->base + IMX_I2C_I2CR);
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temp |= I2CR_RSTA;
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writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
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result = i2c_imx_bus_busy(i2c_imx, 1);
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if (result)
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goto fail0;
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}
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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]);
|
|
if (result)
|
|
goto fail0;
|
|
}
|
|
|
|
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;
|
|
struct imxi2c_platform_data *pdata;
|
|
void __iomem *base;
|
|
resource_size_t res_size;
|
|
int irq;
|
|
int ret;
|
|
|
|
dev_dbg(&pdev->dev, "<%s>\n", __func__);
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
if (!res) {
|
|
dev_err(&pdev->dev, "can't get device resources\n");
|
|
return -ENOENT;
|
|
}
|
|
irq = platform_get_irq(pdev, 0);
|
|
if (irq < 0) {
|
|
dev_err(&pdev->dev, "can't get irq number\n");
|
|
return -ENOENT;
|
|
}
|
|
|
|
pdata = pdev->dev.platform_data;
|
|
|
|
if (pdata && pdata->init) {
|
|
ret = pdata->init(&pdev->dev);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
res_size = resource_size(res);
|
|
|
|
if (!request_mem_region(res->start, res_size, DRIVER_NAME)) {
|
|
ret = -EBUSY;
|
|
goto fail0;
|
|
}
|
|
|
|
base = ioremap(res->start, res_size);
|
|
if (!base) {
|
|
dev_err(&pdev->dev, "ioremap failed\n");
|
|
ret = -EIO;
|
|
goto fail1;
|
|
}
|
|
|
|
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 fail2;
|
|
}
|
|
|
|
/* 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.nr = pdev->id;
|
|
i2c_imx->irq = irq;
|
|
i2c_imx->base = base;
|
|
i2c_imx->res = res;
|
|
|
|
/* Get I2C clock */
|
|
i2c_imx->clk = clk_get(&pdev->dev, "i2c_clk");
|
|
if (IS_ERR(i2c_imx->clk)) {
|
|
ret = PTR_ERR(i2c_imx->clk);
|
|
dev_err(&pdev->dev, "can't get I2C clock\n");
|
|
goto fail3;
|
|
}
|
|
|
|
/* Request IRQ */
|
|
ret = request_irq(i2c_imx->irq, i2c_imx_isr, 0, pdev->name, i2c_imx);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "can't claim irq %d\n", i2c_imx->irq);
|
|
goto fail4;
|
|
}
|
|
|
|
/* Init queue */
|
|
init_waitqueue_head(&i2c_imx->queue);
|
|
|
|
/* Set up adapter data */
|
|
i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
|
|
|
|
/* Set up clock divider */
|
|
if (pdata && pdata->bitrate)
|
|
i2c_imx_set_clk(i2c_imx, pdata->bitrate);
|
|
else
|
|
i2c_imx_set_clk(i2c_imx, IMX_I2C_BIT_RATE);
|
|
|
|
/* 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 fail5;
|
|
}
|
|
|
|
/* Set up platform driver data */
|
|
platform_set_drvdata(pdev, i2c_imx);
|
|
|
|
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 */
|
|
|
|
fail5:
|
|
free_irq(i2c_imx->irq, i2c_imx);
|
|
fail4:
|
|
clk_put(i2c_imx->clk);
|
|
fail3:
|
|
kfree(i2c_imx);
|
|
fail2:
|
|
iounmap(base);
|
|
fail1:
|
|
release_mem_region(res->start, resource_size(res));
|
|
fail0:
|
|
if (pdata && pdata->exit)
|
|
pdata->exit(&pdev->dev);
|
|
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);
|
|
struct imxi2c_platform_data *pdata = pdev->dev.platform_data;
|
|
|
|
/* 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);
|
|
|
|
/* Shut down hardware */
|
|
if (pdata && pdata->exit)
|
|
pdata->exit(&pdev->dev);
|
|
|
|
clk_put(i2c_imx->clk);
|
|
|
|
iounmap(i2c_imx->base);
|
|
release_mem_region(i2c_imx->res->start, resource_size(i2c_imx->res));
|
|
kfree(i2c_imx);
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver i2c_imx_driver = {
|
|
.remove = __exit_p(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);
|
|
}
|
|
subsys_initcall(i2c_adap_imx_init);
|
|
|
|
static void __exit i2c_adap_imx_exit(void)
|
|
{
|
|
platform_driver_unregister(&i2c_imx_driver);
|
|
}
|
|
module_exit(i2c_adap_imx_exit);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Darius Augulis");
|
|
MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus");
|
|
MODULE_ALIAS("platform:" DRIVER_NAME);
|