* [PATCH V3] I2C driver for IMX
@ 2008-04-08 8:01 Darius
2008-04-09 23:28 ` Ben Dooks
2008-04-15 11:03 ` Darius
0 siblings, 2 replies; 11+ messages in thread
From: Darius @ 2008-04-08 8:01 UTC (permalink / raw
To: linux-arm-kernel; +Cc: i2c
[-- Attachment #1: Type: text/plain, Size: 227 bytes --]
changes:
1. Removed hardcoded constants
2. Fixed bug in chip hardware
3. Added i2c device for mx1ads
Tested with mx1ads v2.0 board and LCD on I2C interface driver
Signed-off-by: Darius Augulis <augulis.darius@gmail.com>
---
[-- Attachment #2: patch-i2c-imx-2.6.24 --]
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diff -uprN -X linux-2.6.24.4-orig/Documentation/dontdiff linux-2.6.24.4-orig/arch/arm/mach-imx/mx1ads.c linux-2.6.24.4/arch/arm/mach-imx/mx1ads.c
--- linux-2.6.24.4-orig/arch/arm/mach-imx/mx1ads.c 2008-01-25 00:58:37.000000000 +0200
+++ linux-2.6.24.4/arch/arm/mach-imx/mx1ads.c 2008-04-07 15:28:17.000000000 +0300
@@ -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
diff -uprN -X linux-2.6.24.4-orig/Documentation/dontdiff linux-2.6.24.4-orig/drivers/i2c/busses/i2c-imx.c linux-2.6.24.4/drivers/i2c/busses/i2c-imx.c
--- linux-2.6.24.4-orig/drivers/i2c/busses/i2c-imx.c 1970-01-01 03:00:00.000000000 +0300
+++ linux-2.6.24.4/drivers/i2c/busses/i2c-imx.c 2008-04-08 10:43:08.000000000 +0300
@@ -0,0 +1,611 @@
+/*
+ * 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.
+ *
+ * File Name: i2c-imx.c
+ *
+ * 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
+ * - imxslave:
+ * IMX slave I2C address in decimal format
+ * The default value is 0xAC in hex
+ *
+ * Derived from Motorola GSG China I2C example driver
+ *
+ * Copyright (C) 2002 Motorola GSG-China
+ * 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. <adyer at righthandtech.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/fs.h>
+#include <linux/proc_fs.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+
+#include <asm/arch/irqs.h>
+#include <asm/arch/hardware.h>
+#include <asm/io.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_SLAVE_ADDR 0xAC
+#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 */
+
+/* Error numbers */
+#define I2C_IMX_ERR_BUSY 1
+#define I2C_IMX_ERR_TX_TIMEOUT 2
+#define I2C_IMX_ERR_RX_TIMEOUT 3
+#define I2C_IMX_ERR_RX_NO_ACK 4
+
+/* Macros */
+#define print_err(f,x...) printk(KERN_ERR f, ##x)
+#ifdef CONFIG_I2C_DEBUG_BUS
+#define print_dbg(f,x...) printk(KERN_DEBUG f, ##x)
+#else
+#define print_dbg(f,x...) ((void)0)
+#endif
+
+/** Function prototypes ********************************************************
+*******************************************************************************/
+
+static int i2c_imx_xfer (struct i2c_adapter *adapter, struct i2c_msg *msgs, int num);
+static u32 i2c_imx_func (struct i2c_adapter *adapter);
+static int __init i2c_imx_probe (struct platform_device *pdev);
+static int i2c_imx_remove (struct platform_device *pdev);
+
+/** Variables ******************************************************************
+*******************************************************************************/
+
+static unsigned int clkfreq = IMX_I2C_BIT_RATE;
+static unsigned int imxslave = IMX_I2C_SLAVE_ADDR;
+static unsigned int disable_delay = 0; /* Dummy delay. Default value - 0 (no 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 int __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 }
+};
+
+static struct platform_driver i2c_imx_driver = {
+ .probe = i2c_imx_probe,
+ .remove = i2c_imx_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ }
+};
+
+static struct i2c_algorithm i2c_imx_algo = {
+ .master_xfer = i2c_imx_xfer,
+ .functionality = i2c_imx_func,
+};
+
+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;
+
+ print_dbg("I2C: <i2c_imx_bus_busy>\n");
+
+ /* 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);
+ }
+ print_dbg("I2C: <i2c_imx_bus_busy> I2C bus is busy!\n");
+ return -I2C_IMX_ERR_BUSY;
+}
+
+static int i2c_imx_trx_complete (struct imx_i2c_struct *i2c_imx) {
+
+ int result;
+
+ print_dbg("I2C: <i2c_imx_trx_complete>\n");
+ result = wait_event_interruptible_timeout(i2c_imx->queue,
+ (i2c_imx->i2csr & I2SR_IIF), I2C_IMX_TIME_TRX * HZ);
+
+ if (unlikely(result < 0)) {
+ print_dbg("I2C: <i2c_imx_trx_complete> result < 0!\n");
+ return result;
+ }
+ else if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
+ print_dbg("I2C: <i2c_imx_trx_complete> Timeout!\n");
+ return -I2C_IMX_ERR_TX_TIMEOUT;
+ }
+ print_dbg("I2C: <i2c_imx_trx_complete> TRX complete!\n");
+ i2c_imx->i2csr = 0;
+ return 0;
+}
+
+static int i2c_imx_acked (struct imx_i2c_struct *i2c_imx) {
+
+ unsigned int i = 0;
+
+ print_dbg("I2C: <i2c_imx_acked>\n");
+ for (i=0; i<I2C_IMX_TIME_ACK; i++) {
+ if (!(readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK)) {
+ print_dbg("I2C: <i2c_imx_acked> ACK received\n");
+ return 0;
+ }
+ udelay(1);
+ }
+ print_dbg("I2C: <i2c_imx_acked> No ACK!\n");
+ return -I2C_IMX_ERR_RX_NO_ACK; /* No ACK */
+}
+
+static void i2c_imx_enable (struct imx_i2c_struct *i2c_imx) {
+
+ print_dbg("I2C: <i2c_imx_enable>\n");
+ writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
+}
+
+static void i2c_imx_disable (struct imx_i2c_struct *i2c_imx) {
+
+ print_dbg("I2C: <i2c_imx_disable>\n");
+
+ /* 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 i.MXL hardware bug. If no (or to short) delay, no "STOP" bit will be generated */
+ udelay(disable_delay);
+ writeb(0, i2c_imx->base + IMX_I2C_I2CR);
+}
+
+static void i2c_imx_start (struct imx_i2c_struct *i2c_imx) {
+
+ unsigned int temp = 0;
+
+ print_dbg("I2C: <i2c_imx_start>\n");
+ 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);
+
+ temp = readb (i2c_imx->base + IMX_I2C_I2CR);
+ print_dbg("I2C: <i2c_imx_start> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n",
+ (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);
+ print_dbg("I2C: <i2c_imx_start> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n",
+ (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));
+}
+
+static void i2c_imx_stop (struct imx_i2c_struct *i2c_imx) {
+
+ unsigned int temp = 0;
+
+ print_dbg("I2C: <i2c_imx_stop>\n");
+ temp = readb ( i2c_imx->base + IMX_I2C_I2CR);
+ temp &= ~I2CR_MSTA;
+ writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
+ temp = readb (i2c_imx->base + IMX_I2C_I2CR);
+ print_dbg("I2C: <i2c_imx_stop> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n",
+ (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);
+ print_dbg("I2C: <i2c_imx_stop> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n",
+ (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));
+}
+
+static int __init i2c_imx_set_clk (struct imx_i2c_struct *i2c_imx, unsigned int rate) {
+
+ unsigned int hclk, sysclk;
+ unsigned int desired_div;
+ int i;
+
+ print_dbg("I2C: <i2c_imx_set_clk>\n");
+ sysclk = imx_get_system_clk ();
+ hclk = imx_get_hclk();
+ desired_div = hclk / rate;
+ if (desired_div & 0x01)
+ desired_div++;
+ if (desired_div < 22)
+ desired_div = 22;
+ if (desired_div > 3840)
+ desired_div = 3840;
+ for (i=0; i<50; i++) {
+ if (i2c_imx_clk_divider[i][0] >= desired_div)
+ break;
+ }
+
+ /*
+ * 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 = (1000000 / (hclk / i2c_imx_clk_divider[i][0])) + 1;
+
+ print_dbg("I2C: <i2c_imx_set_clk> SYSCLK=%d, HCLK=%d, REQ DIV=%d\n", sysclk, hclk, desired_div);
+ print_dbg("I2C: <i2c_imx_set_clk> IFDR[IC]=0x%x, REAL DIV=%d\n", i2c_imx_clk_divider[i][1], i2c_imx_clk_divider[i][0]);
+ writeb(i2c_imx_clk_divider[i][1], i2c_imx->base + IMX_I2C_IFDR);
+ return 0;
+}
+
+static irqreturn_t i2c_imx_isr (int irq, void *dev_id) {
+
+ struct imx_i2c_struct *i2c_imx = dev_id;
+ unsigned int temp;
+
+ print_dbg("I2C: <i2c_imx_isr>\n");
+ temp = readb (i2c_imx->base + IMX_I2C_I2CR);
+ print_dbg("I2C: <i2c_imx_isr> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n",
+ (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);
+ print_dbg("I2C: <i2c_imx_isr> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n",
+ (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));
+
+ 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;
+
+ print_dbg("I2C: <i2c_imx_write>\n");
+ print_dbg("I2C: <i2c_imx_write> write slave address: addr=0x%x\n", (msgs->addr<<1));
+
+ /* write slave address */
+ writeb((msgs->addr<<1), i2c_imx->base + IMX_I2C_I2DR);
+ if (i2c_imx_trx_complete(i2c_imx))
+ return -I2C_IMX_ERR_TX_TIMEOUT;
+ if (i2c_imx_acked(i2c_imx))
+ return -I2C_IMX_ERR_RX_NO_ACK;
+ print_dbg("I2C: <i2c_imx_write> write data\n");
+
+ /* write data */
+ for (i = 0; i<msgs->len; i++) {
+ print_dbg("I2C: <i2c_imx_write> write byte: %d, b=0x%x\n", i, msgs->buf[i]);
+ writeb(msgs->buf[i], i2c_imx->base + IMX_I2C_I2DR);
+ if (i2c_imx_trx_complete(i2c_imx))
+ return -I2C_IMX_ERR_TX_TIMEOUT;
+ if (i2c_imx_acked(i2c_imx))
+ return -I2C_IMX_ERR_RX_NO_ACK;
+ }
+ return 0;
+}
+
+static int i2c_imx_read (struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs) {
+
+ int i;
+ unsigned int temp;
+
+ print_dbg("I2C: <i2c_imx_read>\n");
+ print_dbg("I2C: <i2c_imx_read> write slave address: addr=0x%x\n", (msgs->addr<<1));
+
+ /* write slave address */
+ writeb((msgs->addr<<1)|0x01, i2c_imx->base + IMX_I2C_I2DR);
+ if (i2c_imx_trx_complete(i2c_imx))
+ return -I2C_IMX_ERR_TX_TIMEOUT;
+ if (i2c_imx_acked(i2c_imx))
+ return -I2C_IMX_ERR_RX_NO_ACK;
+
+ print_dbg("I2C: <i2c_imx_read> setup bus\n");
+
+ /* 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);
+
+ print_dbg("I2C: <i2c_imx_read> dummy read\n");
+ readb(i2c_imx->base + IMX_I2C_I2DR); /* dummy read */
+
+ print_dbg("I2C: <i2c_imx_read> read data\n");
+
+ /* read data */
+ for (i=0; i < msgs->len; i++) {
+
+ if (i2c_imx_trx_complete(i2c_imx))
+ return -I2C_IMX_ERR_RX_TIMEOUT;
+
+ if (i==(msgs->len-1)) {
+ print_dbg("I2C: <i2c_imx_read> clear MSTA\n");
+ 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)) {
+ print_dbg("I2C: <i2c_imx_read> set TXAK\n");
+ temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+ temp |= I2CR_TXAK;
+ writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
+ }
+ print_dbg("I2C: <i2c_imx_read> read byte B%d\n", i);
+ msgs->buf[i] = readb(i2c_imx->base + IMX_I2C_I2DR);
+ }
+ return 0;
+}
+
+static int i2c_imx_xfer (struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) {
+
+ int i, temp;
+ int err = 0;
+ struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
+
+ print_dbg("I2C: <i2c_imx_xfer>\n");
+
+ /* Check or i2c bus is not busy */
+ err = i2c_imx_bus_busy(i2c_imx);
+ if (err)
+ goto fail0;
+
+ /* Enable i2c */
+ i2c_imx_enable(i2c_imx);
+
+ /* Start I2C transfer */
+ i2c_imx_start (i2c_imx);
+
+ temp = readb (i2c_imx->base + IMX_I2C_I2CR);
+ print_dbg("I2C: <i2c_imx_xfer> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n",
+ (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);
+ print_dbg("I2C: <i2c_imx_xfer> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n",
+ (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));
+
+ /* read/write data */
+ for (i=0; i<num; i++) {
+ if (i) {
+ print_dbg("I2C: <i2c_imx_read> repeated start\n");
+ temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+ temp |= I2CR_RSTA;
+ writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
+ }
+ print_dbg("I2C: <i2c_imx_xfer> transfer message: %d\n", i);
+ /* write/read data */
+ if (!(msgs[i].flags & I2C_M_RD))
+ err = i2c_imx_write (i2c_imx, &msgs[i]);
+ else
+ err = i2c_imx_read (i2c_imx, &msgs[i]);
+ }
+
+fail0:
+ /* Stop bus */
+ i2c_imx_stop (i2c_imx);
+ /* disable i2c bus */
+ i2c_imx_disable (i2c_imx);
+ print_dbg("I2C: <i2c_imx_xfer> exit with: %s: %d\n", (err < 0)?"error":"success msg", (err < 0)?err:num);
+ return (err < 0) ? err : num;
+}
+
+static u32 i2c_imx_func (struct i2c_adapter *adapter) {
+ return I2C_FUNC_I2C;
+}
+
+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;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ irq = platform_get_irq(pdev, 0);
+ if (!res) {
+ print_err("I2C: can't get device resources!\n");
+ return -ENODEV;
+ }
+ if (irq < 0) {
+ print_err("I2C: 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)) {
+ print_err("I2C: can't allocate %d bytes at %d address!\n", res_size, res->start);
+ return -ENOMEM;
+ }
+ base = ioremap (res->start, res_size);
+ if (!base) {
+ print_err("I2C: ioremap failed!\n");
+ ret = -EIO;
+ goto fail0;
+ }
+ i2c_imx = kzalloc(sizeof(struct imx_i2c_struct), GFP_KERNEL);
+ if (!i2c_imx) {
+ print_err("I2C: 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->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) {
+ print_err("I2C: %s: cannot claim irq %d !\n", i2c_imx->adapter.dev.bus_id, i2c_imx->irq);
+ goto fail2;
+ }
+
+ /* Set up clock divider */
+ i2c_imx_set_clk(i2c_imx, clkfreq);
+
+ /* Set up IMX I2C slave address */
+ writeb(imxslave, i2c_imx->base + IMX_I2C_IADR);
+
+ /* 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);
+
+ /* Set up adapter data */
+ i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
+
+ /* Add I2C adapter */
+ ret = i2c_add_adapter(&i2c_imx->adapter);
+ if (ret < 0) {
+ print_err("I2C: %s: registration failed\n", i2c_imx->adapter.dev.bus_id);
+ goto fail3;
+ }
+
+ print_dbg("I2C: %s: claimed irq %d\n", i2c_imx->adapter.dev.bus_id, i2c_imx->irq);
+ print_dbg("I2C: %s: device resources from 0x%x to 0x%x\n", i2c_imx->adapter.dev.bus_id, i2c_imx->res->start, i2c_imx->res->end);
+ print_dbg("I2C: %s: allocated %d bytes at 0x%x \n", i2c_imx->adapter.dev.bus_id, res_size, i2c_imx->res->start);
+ print_dbg("I2C: %s: adapter name: \"%s\"\n", i2c_imx->adapter.dev.bus_id, i2c_imx->adapter.name);
+ print_dbg("I2C: adapter \"%s\" associated with driver \"%s\"\n", i2c_imx->adapter.dev.bus_id, i2c_imx_driver.driver.name);
+ print_dbg("I2C: %s: IMX I2C adapter registered\n", i2c_imx->adapter.dev.bus_id);
+ 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 i2c_imx_remove (struct platform_device *pdev) {
+
+ struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
+
+ /* remove adapter */
+ print_dbg("I2C: 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 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_AUTHOR("Darius Augulis");
+MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus");
+MODULE_LICENSE("GPL");
+
+module_param(clkfreq, uint, S_IRUGO);
+MODULE_PARM_DESC(clkfreq, "desired IMX I2C Clock Rate in Hz");
+
+module_param(imxslave, uint, S_IRUGO);
+MODULE_PARM_DESC(imxslave, "desired IMX I2C slave address");
diff -uprN -X linux-2.6.24.4-orig/Documentation/dontdiff linux-2.6.24.4-orig/drivers/i2c/busses/Kconfig linux-2.6.24.4/drivers/i2c/busses/Kconfig
--- linux-2.6.24.4-orig/drivers/i2c/busses/Kconfig 2008-01-25 00:58:37.000000000 +0200
+++ linux-2.6.24.4/drivers/i2c/busses/Kconfig 2008-04-07 15:33:28.000000000 +0300
@@ -249,6 +249,16 @@ 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
diff -uprN -X linux-2.6.24.4-orig/Documentation/dontdiff linux-2.6.24.4-orig/drivers/i2c/busses/Makefile linux-2.6.24.4/drivers/i2c/busses/Makefile
--- linux-2.6.24.4-orig/drivers/i2c/busses/Makefile 2008-01-25 00:58:37.000000000 +0200
+++ linux-2.6.24.4/drivers/i2c/busses/Makefile 2008-04-07 15:33:28.000000000 +0300
@@ -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_IXP4XX) += i2c-ixp4xx.o
diff -uprN -X linux-2.6.24.4-orig/Documentation/dontdiff linux-2.6.24.4-orig/include/asm-arm/arch-imx/imx-regs.h linux-2.6.24.4/include/asm-arm/arch-imx/imx-regs.h
--- linux-2.6.24.4-orig/include/asm-arm/arch-imx/imx-regs.h 2008-01-25 00:58:37.000000000 +0200
+++ linux-2.6.24.4/include/asm-arm/arch-imx/imx-regs.h 2008-04-07 15:33:28.000000000 +0300
@@ -479,4 +479,29 @@
#define LCDISR_EOF (1<<1)
#define LCDISR_BOF (1<<0)
+/*
+ * I2C
+ */
+
+#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 */
+
+#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
+
#endif // _IMX_REGS_H
[-- Attachment #3: Type: text/plain, Size: 271 bytes --]
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^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3] I2C driver for IMX
2008-04-08 8:01 [PATCH V3] I2C driver for IMX Darius
@ 2008-04-09 23:28 ` Ben Dooks
[not found] ` <20080409232834.GG1197-SMNkleLxa3Z6Wcw2j4pizdi2O/JbrIOy@public.gmane.org>
2008-04-15 11:03 ` Darius
1 sibling, 1 reply; 11+ messages in thread
From: Ben Dooks @ 2008-04-09 23:28 UTC (permalink / raw
To: Darius; +Cc: linux-arm-kernel, i2c
On Tue, Apr 08, 2008 at 11:01:25AM +0300, Darius wrote:
> changes:
> 1. Removed hardcoded constants
> 2. Fixed bug in chip hardware
> 3. Added i2c device for mx1ads
>
> Tested with mx1ads v2.0 board and LCD on I2C interface driver
>
> Signed-off-by: Darius Augulis <augulis.darius@gmail.com>
> ---
Hmm, this hasn't appeared on the i2c list where it should be being
reviewed before submission. Not bothered to look or snip the rest.
> diff -uprN -X linux-2.6.24.4-orig/Documentation/dontdiff linux-2.6.24.4-orig/arch/arm/mach-imx/mx1ads.c linux-2.6.24.4/arch/arm/mach-imx/mx1ads.c
> --- linux-2.6.24.4-orig/arch/arm/mach-imx/mx1ads.c 2008-01-25 00:58:37.000000000 +0200
> +++ linux-2.6.24.4/arch/arm/mach-imx/mx1ads.c 2008-04-07 15:28:17.000000000 +0300
> @@ -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
> diff -uprN -X linux-2.6.24.4-orig/Documentation/dontdiff linux-2.6.24.4-orig/drivers/i2c/busses/i2c-imx.c linux-2.6.24.4/drivers/i2c/busses/i2c-imx.c
> --- linux-2.6.24.4-orig/drivers/i2c/busses/i2c-imx.c 1970-01-01 03:00:00.000000000 +0300
> +++ linux-2.6.24.4/drivers/i2c/busses/i2c-imx.c 2008-04-08 10:43:08.000000000 +0300
> @@ -0,0 +1,611 @@
> +/*
> + * 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.
> + *
> + * File Name: i2c-imx.c
> + *
> + * 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
> + * - imxslave:
> + * IMX slave I2C address in decimal format
> + * The default value is 0xAC in hex
> + *
> + * Derived from Motorola GSG China I2C example driver
> + *
> + * Copyright (C) 2002 Motorola GSG-China
> + * 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. <adyer at righthandtech.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/fs.h>
> +#include <linux/proc_fs.h>
> +#include <linux/errno.h>
> +#include <linux/interrupt.h>
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/platform_device.h>
> +
> +#include <asm/arch/irqs.h>
> +#include <asm/arch/hardware.h>
> +#include <asm/io.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_SLAVE_ADDR 0xAC
> +#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 */
> +
> +/* Error numbers */
> +#define I2C_IMX_ERR_BUSY 1
> +#define I2C_IMX_ERR_TX_TIMEOUT 2
> +#define I2C_IMX_ERR_RX_TIMEOUT 3
> +#define I2C_IMX_ERR_RX_NO_ACK 4
> +
> +/* Macros */
> +#define print_err(f,x...) printk(KERN_ERR f, ##x)
> +#ifdef CONFIG_I2C_DEBUG_BUS
> +#define print_dbg(f,x...) printk(KERN_DEBUG f, ##x)
> +#else
> +#define print_dbg(f,x...) ((void)0)
> +#endif
> +
> +/** Function prototypes ********************************************************
> +*******************************************************************************/
> +
> +static int i2c_imx_xfer (struct i2c_adapter *adapter, struct i2c_msg *msgs, int num);
> +static u32 i2c_imx_func (struct i2c_adapter *adapter);
> +static int __init i2c_imx_probe (struct platform_device *pdev);
> +static int i2c_imx_remove (struct platform_device *pdev);
> +
> +/** Variables ******************************************************************
> +*******************************************************************************/
> +
> +static unsigned int clkfreq = IMX_I2C_BIT_RATE;
> +static unsigned int imxslave = IMX_I2C_SLAVE_ADDR;
> +static unsigned int disable_delay = 0; /* Dummy delay. Default value - 0 (no 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 int __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 }
> +};
> +
> +static struct platform_driver i2c_imx_driver = {
> + .probe = i2c_imx_probe,
> + .remove = i2c_imx_remove,
> + .driver = {
> + .name = DRIVER_NAME,
> + .owner = THIS_MODULE,
> + }
> +};
> +
> +static struct i2c_algorithm i2c_imx_algo = {
> + .master_xfer = i2c_imx_xfer,
> + .functionality = i2c_imx_func,
> +};
> +
> +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;
> +
> + print_dbg("I2C: <i2c_imx_bus_busy>\n");
> +
> + /* 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);
> + }
> + print_dbg("I2C: <i2c_imx_bus_busy> I2C bus is busy!\n");
> + return -I2C_IMX_ERR_BUSY;
> +}
> +
> +static int i2c_imx_trx_complete (struct imx_i2c_struct *i2c_imx) {
> +
> + int result;
> +
> + print_dbg("I2C: <i2c_imx_trx_complete>\n");
> + result = wait_event_interruptible_timeout(i2c_imx->queue,
> + (i2c_imx->i2csr & I2SR_IIF), I2C_IMX_TIME_TRX * HZ);
> +
> + if (unlikely(result < 0)) {
> + print_dbg("I2C: <i2c_imx_trx_complete> result < 0!\n");
> + return result;
> + }
> + else if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
> + print_dbg("I2C: <i2c_imx_trx_complete> Timeout!\n");
> + return -I2C_IMX_ERR_TX_TIMEOUT;
> + }
> + print_dbg("I2C: <i2c_imx_trx_complete> TRX complete!\n");
> + i2c_imx->i2csr = 0;
> + return 0;
> +}
> +
> +static int i2c_imx_acked (struct imx_i2c_struct *i2c_imx) {
> +
> + unsigned int i = 0;
> +
> + print_dbg("I2C: <i2c_imx_acked>\n");
> + for (i=0; i<I2C_IMX_TIME_ACK; i++) {
> + if (!(readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK)) {
> + print_dbg("I2C: <i2c_imx_acked> ACK received\n");
> + return 0;
> + }
> + udelay(1);
> + }
> + print_dbg("I2C: <i2c_imx_acked> No ACK!\n");
> + return -I2C_IMX_ERR_RX_NO_ACK; /* No ACK */
> +}
> +
> +static void i2c_imx_enable (struct imx_i2c_struct *i2c_imx) {
> +
> + print_dbg("I2C: <i2c_imx_enable>\n");
> + writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
> +}
> +
> +static void i2c_imx_disable (struct imx_i2c_struct *i2c_imx) {
> +
> + print_dbg("I2C: <i2c_imx_disable>\n");
> +
> + /* 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 i.MXL hardware bug. If no (or to short) delay, no "STOP" bit will be generated */
> + udelay(disable_delay);
> + writeb(0, i2c_imx->base + IMX_I2C_I2CR);
> +}
> +
> +static void i2c_imx_start (struct imx_i2c_struct *i2c_imx) {
> +
> + unsigned int temp = 0;
> +
> + print_dbg("I2C: <i2c_imx_start>\n");
> + 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);
> +
> + temp = readb (i2c_imx->base + IMX_I2C_I2CR);
> + print_dbg("I2C: <i2c_imx_start> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n",
> + (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);
> + print_dbg("I2C: <i2c_imx_start> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n",
> + (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));
> +}
> +
> +static void i2c_imx_stop (struct imx_i2c_struct *i2c_imx) {
> +
> + unsigned int temp = 0;
> +
> + print_dbg("I2C: <i2c_imx_stop>\n");
> + temp = readb ( i2c_imx->base + IMX_I2C_I2CR);
> + temp &= ~I2CR_MSTA;
> + writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
> + temp = readb (i2c_imx->base + IMX_I2C_I2CR);
> + print_dbg("I2C: <i2c_imx_stop> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n",
> + (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);
> + print_dbg("I2C: <i2c_imx_stop> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n",
> + (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));
> +}
> +
> +static int __init i2c_imx_set_clk (struct imx_i2c_struct *i2c_imx, unsigned int rate) {
> +
> + unsigned int hclk, sysclk;
> + unsigned int desired_div;
> + int i;
> +
> + print_dbg("I2C: <i2c_imx_set_clk>\n");
> + sysclk = imx_get_system_clk ();
> + hclk = imx_get_hclk();
> + desired_div = hclk / rate;
> + if (desired_div & 0x01)
> + desired_div++;
> + if (desired_div < 22)
> + desired_div = 22;
> + if (desired_div > 3840)
> + desired_div = 3840;
> + for (i=0; i<50; i++) {
> + if (i2c_imx_clk_divider[i][0] >= desired_div)
> + break;
> + }
> +
> + /*
> + * 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 = (1000000 / (hclk / i2c_imx_clk_divider[i][0])) + 1;
> +
> + print_dbg("I2C: <i2c_imx_set_clk> SYSCLK=%d, HCLK=%d, REQ DIV=%d\n", sysclk, hclk, desired_div);
> + print_dbg("I2C: <i2c_imx_set_clk> IFDR[IC]=0x%x, REAL DIV=%d\n", i2c_imx_clk_divider[i][1], i2c_imx_clk_divider[i][0]);
> + writeb(i2c_imx_clk_divider[i][1], i2c_imx->base + IMX_I2C_IFDR);
> + return 0;
> +}
> +
> +static irqreturn_t i2c_imx_isr (int irq, void *dev_id) {
> +
> + struct imx_i2c_struct *i2c_imx = dev_id;
> + unsigned int temp;
> +
> + print_dbg("I2C: <i2c_imx_isr>\n");
> + temp = readb (i2c_imx->base + IMX_I2C_I2CR);
> + print_dbg("I2C: <i2c_imx_isr> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n",
> + (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);
> + print_dbg("I2C: <i2c_imx_isr> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n",
> + (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));
> +
> + 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;
> +
> + print_dbg("I2C: <i2c_imx_write>\n");
> + print_dbg("I2C: <i2c_imx_write> write slave address: addr=0x%x\n", (msgs->addr<<1));
> +
> + /* write slave address */
> + writeb((msgs->addr<<1), i2c_imx->base + IMX_I2C_I2DR);
> + if (i2c_imx_trx_complete(i2c_imx))
> + return -I2C_IMX_ERR_TX_TIMEOUT;
> + if (i2c_imx_acked(i2c_imx))
> + return -I2C_IMX_ERR_RX_NO_ACK;
> + print_dbg("I2C: <i2c_imx_write> write data\n");
> +
> + /* write data */
> + for (i = 0; i<msgs->len; i++) {
> + print_dbg("I2C: <i2c_imx_write> write byte: %d, b=0x%x\n", i, msgs->buf[i]);
> + writeb(msgs->buf[i], i2c_imx->base + IMX_I2C_I2DR);
> + if (i2c_imx_trx_complete(i2c_imx))
> + return -I2C_IMX_ERR_TX_TIMEOUT;
> + if (i2c_imx_acked(i2c_imx))
> + return -I2C_IMX_ERR_RX_NO_ACK;
> + }
> + return 0;
> +}
> +
> +static int i2c_imx_read (struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs) {
> +
> + int i;
> + unsigned int temp;
> +
> + print_dbg("I2C: <i2c_imx_read>\n");
> + print_dbg("I2C: <i2c_imx_read> write slave address: addr=0x%x\n", (msgs->addr<<1));
> +
> + /* write slave address */
> + writeb((msgs->addr<<1)|0x01, i2c_imx->base + IMX_I2C_I2DR);
> + if (i2c_imx_trx_complete(i2c_imx))
> + return -I2C_IMX_ERR_TX_TIMEOUT;
> + if (i2c_imx_acked(i2c_imx))
> + return -I2C_IMX_ERR_RX_NO_ACK;
> +
> + print_dbg("I2C: <i2c_imx_read> setup bus\n");
> +
> + /* 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);
> +
> + print_dbg("I2C: <i2c_imx_read> dummy read\n");
> + readb(i2c_imx->base + IMX_I2C_I2DR); /* dummy read */
> +
> + print_dbg("I2C: <i2c_imx_read> read data\n");
> +
> + /* read data */
> + for (i=0; i < msgs->len; i++) {
> +
> + if (i2c_imx_trx_complete(i2c_imx))
> + return -I2C_IMX_ERR_RX_TIMEOUT;
> +
> + if (i==(msgs->len-1)) {
> + print_dbg("I2C: <i2c_imx_read> clear MSTA\n");
> + 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)) {
> + print_dbg("I2C: <i2c_imx_read> set TXAK\n");
> + temp = readb(i2c_imx->base + IMX_I2C_I2CR);
> + temp |= I2CR_TXAK;
> + writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
> + }
> + print_dbg("I2C: <i2c_imx_read> read byte B%d\n", i);
> + msgs->buf[i] = readb(i2c_imx->base + IMX_I2C_I2DR);
> + }
> + return 0;
> +}
> +
> +static int i2c_imx_xfer (struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) {
> +
> + int i, temp;
> + int err = 0;
> + struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
> +
> + print_dbg("I2C: <i2c_imx_xfer>\n");
> +
> + /* Check or i2c bus is not busy */
> + err = i2c_imx_bus_busy(i2c_imx);
> + if (err)
> + goto fail0;
> +
> + /* Enable i2c */
> + i2c_imx_enable(i2c_imx);
> +
> + /* Start I2C transfer */
> + i2c_imx_start (i2c_imx);
> +
> + temp = readb (i2c_imx->base + IMX_I2C_I2CR);
> + print_dbg("I2C: <i2c_imx_xfer> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n",
> + (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);
> + print_dbg("I2C: <i2c_imx_xfer> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n",
> + (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));
> +
> + /* read/write data */
> + for (i=0; i<num; i++) {
> + if (i) {
> + print_dbg("I2C: <i2c_imx_read> repeated start\n");
> + temp = readb(i2c_imx->base + IMX_I2C_I2CR);
> + temp |= I2CR_RSTA;
> + writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
> + }
> + print_dbg("I2C: <i2c_imx_xfer> transfer message: %d\n", i);
> + /* write/read data */
> + if (!(msgs[i].flags & I2C_M_RD))
> + err = i2c_imx_write (i2c_imx, &msgs[i]);
> + else
> + err = i2c_imx_read (i2c_imx, &msgs[i]);
> + }
> +
> +fail0:
> + /* Stop bus */
> + i2c_imx_stop (i2c_imx);
> + /* disable i2c bus */
> + i2c_imx_disable (i2c_imx);
> + print_dbg("I2C: <i2c_imx_xfer> exit with: %s: %d\n", (err < 0)?"error":"success msg", (err < 0)?err:num);
> + return (err < 0) ? err : num;
> +}
> +
> +static u32 i2c_imx_func (struct i2c_adapter *adapter) {
> + return I2C_FUNC_I2C;
> +}
> +
> +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;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + irq = platform_get_irq(pdev, 0);
> + if (!res) {
> + print_err("I2C: can't get device resources!\n");
> + return -ENODEV;
> + }
> + if (irq < 0) {
> + print_err("I2C: 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)) {
> + print_err("I2C: can't allocate %d bytes at %d address!\n", res_size, res->start);
> + return -ENOMEM;
> + }
> + base = ioremap (res->start, res_size);
> + if (!base) {
> + print_err("I2C: ioremap failed!\n");
> + ret = -EIO;
> + goto fail0;
> + }
> + i2c_imx = kzalloc(sizeof(struct imx_i2c_struct), GFP_KERNEL);
> + if (!i2c_imx) {
> + print_err("I2C: 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->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) {
> + print_err("I2C: %s: cannot claim irq %d !\n", i2c_imx->adapter.dev.bus_id, i2c_imx->irq);
> + goto fail2;
> + }
> +
> + /* Set up clock divider */
> + i2c_imx_set_clk(i2c_imx, clkfreq);
> +
> + /* Set up IMX I2C slave address */
> + writeb(imxslave, i2c_imx->base + IMX_I2C_IADR);
> +
> + /* 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);
> +
> + /* Set up adapter data */
> + i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
> +
> + /* Add I2C adapter */
> + ret = i2c_add_adapter(&i2c_imx->adapter);
> + if (ret < 0) {
> + print_err("I2C: %s: registration failed\n", i2c_imx->adapter.dev.bus_id);
> + goto fail3;
> + }
> +
> + print_dbg("I2C: %s: claimed irq %d\n", i2c_imx->adapter.dev.bus_id, i2c_imx->irq);
> + print_dbg("I2C: %s: device resources from 0x%x to 0x%x\n", i2c_imx->adapter.dev.bus_id, i2c_imx->res->start, i2c_imx->res->end);
> + print_dbg("I2C: %s: allocated %d bytes at 0x%x \n", i2c_imx->adapter.dev.bus_id, res_size, i2c_imx->res->start);
> + print_dbg("I2C: %s: adapter name: \"%s\"\n", i2c_imx->adapter.dev.bus_id, i2c_imx->adapter.name);
> + print_dbg("I2C: adapter \"%s\" associated with driver \"%s\"\n", i2c_imx->adapter.dev.bus_id, i2c_imx_driver.driver.name);
> + print_dbg("I2C: %s: IMX I2C adapter registered\n", i2c_imx->adapter.dev.bus_id);
> + 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 i2c_imx_remove (struct platform_device *pdev) {
> +
> + struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
> +
> + /* remove adapter */
> + print_dbg("I2C: 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 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_AUTHOR("Darius Augulis");
> +MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus");
> +MODULE_LICENSE("GPL");
> +
> +module_param(clkfreq, uint, S_IRUGO);
> +MODULE_PARM_DESC(clkfreq, "desired IMX I2C Clock Rate in Hz");
> +
> +module_param(imxslave, uint, S_IRUGO);
> +MODULE_PARM_DESC(imxslave, "desired IMX I2C slave address");
> diff -uprN -X linux-2.6.24.4-orig/Documentation/dontdiff linux-2.6.24.4-orig/drivers/i2c/busses/Kconfig linux-2.6.24.4/drivers/i2c/busses/Kconfig
> --- linux-2.6.24.4-orig/drivers/i2c/busses/Kconfig 2008-01-25 00:58:37.000000000 +0200
> +++ linux-2.6.24.4/drivers/i2c/busses/Kconfig 2008-04-07 15:33:28.000000000 +0300
> @@ -249,6 +249,16 @@ 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
> diff -uprN -X linux-2.6.24.4-orig/Documentation/dontdiff linux-2.6.24.4-orig/drivers/i2c/busses/Makefile linux-2.6.24.4/drivers/i2c/busses/Makefile
> --- linux-2.6.24.4-orig/drivers/i2c/busses/Makefile 2008-01-25 00:58:37.000000000 +0200
> +++ linux-2.6.24.4/drivers/i2c/busses/Makefile 2008-04-07 15:33:28.000000000 +0300
> @@ -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_IXP4XX) += i2c-ixp4xx.o
> diff -uprN -X linux-2.6.24.4-orig/Documentation/dontdiff linux-2.6.24.4-orig/include/asm-arm/arch-imx/imx-regs.h linux-2.6.24.4/include/asm-arm/arch-imx/imx-regs.h
> --- linux-2.6.24.4-orig/include/asm-arm/arch-imx/imx-regs.h 2008-01-25 00:58:37.000000000 +0200
> +++ linux-2.6.24.4/include/asm-arm/arch-imx/imx-regs.h 2008-04-07 15:33:28.000000000 +0300
> @@ -479,4 +479,29 @@
> #define LCDISR_EOF (1<<1)
> #define LCDISR_BOF (1<<0)
>
> +/*
> + * I2C
> + */
> +
> +#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 */
> +
> +#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
> +
> #endif // _IMX_REGS_H
> -------------------------------------------------------------------
> List admin: http://lists.arm.linux.org.uk/mailman/listinfo/linux-arm-kernel
> FAQ: http://www.arm.linux.org.uk/mailinglists/faq.php
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--
--
Ben
Q: What's a light-year?
A: One-third less calories than a regular year.
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^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3] I2C driver for IMX
[not found] ` <20080409232834.GG1197-SMNkleLxa3Z6Wcw2j4pizdi2O/JbrIOy@public.gmane.org>
@ 2008-04-10 3:25 ` Kumar Gala
2008-04-10 10:01 ` Jean Delvare
0 siblings, 1 reply; 11+ messages in thread
From: Kumar Gala @ 2008-04-10 3:25 UTC (permalink / raw
To: Ben Dooks
Cc: Darius, linux-arm-kernel-xIg/pKzrS19vn6HldHNs0ANdhmdF6hFW,
i2c-GZX6beZjE8VD60Wz+7aTrA
On Thu, 10 Apr 2008, Ben Dooks wrote:
> On Tue, Apr 08, 2008 at 11:01:25AM +0300, Darius wrote:
> > changes:
> > 1. Removed hardcoded constants
> > 2. Fixed bug in chip hardware
> > 3. Added i2c device for mx1ads
> >
> > Tested with mx1ads v2.0 board and LCD on I2C interface driver
> >
> > Signed-off-by: Darius Augulis <augulis.darius-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> > ---
>
> Hmm, this hasn't appeared on the i2c list where it should be being
> reviewed before submission. Not bothered to look or snip the rest.
>
looking at this it seems the HW is identical to the driver handled by
i2c-mpc.c. (which is used on Motorola and now Freescale PPC chips).
- k
_______________________________________________
i2c mailing list
i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org
http://lists.lm-sensors.org/mailman/listinfo/i2c
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3] I2C driver for IMX
2008-04-10 3:25 ` Kumar Gala
@ 2008-04-10 10:01 ` Jean Delvare
[not found] ` <20080410120141.4d220d27-ig7AzVSIIG7kN2dkZ6Wm7A@public.gmane.org>
2008-04-10 10:33 ` Darius
0 siblings, 2 replies; 11+ messages in thread
From: Jean Delvare @ 2008-04-10 10:01 UTC (permalink / raw
To: Kumar Gala; +Cc: Darius, linux-arm-kernel, i2c, Ben Dooks
On Wed, 9 Apr 2008 22:25:39 -0500 (CDT), Kumar Gala wrote:
>
> On Thu, 10 Apr 2008, Ben Dooks wrote:
>
> > On Tue, Apr 08, 2008 at 11:01:25AM +0300, Darius wrote:
> > > changes:
> > > 1. Removed hardcoded constants
> > > 2. Fixed bug in chip hardware
> > > 3. Added i2c device for mx1ads
> > >
> > > Tested with mx1ads v2.0 board and LCD on I2C interface driver
> > >
> > > Signed-off-by: Darius Augulis <augulis.darius@gmail.com>
> > > ---
> >
> > Hmm, this hasn't appeared on the i2c list where it should be being
> > reviewed before submission. Not bothered to look or snip the rest.
>
> looking at this it seems the HW is identical to the driver handled by
> i2c-mpc.c. (which is used on Motorola and now Freescale PPC chips).
Then I guess that we want to add support to the i2c-mpc driver rather
than adding another driver to the kernel tree?
--
Jean Delvare
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^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3] I2C driver for IMX
[not found] ` <20080410120141.4d220d27-ig7AzVSIIG7kN2dkZ6Wm7A@public.gmane.org>
@ 2008-04-10 10:09 ` Kumar Gala
0 siblings, 0 replies; 11+ messages in thread
From: Kumar Gala @ 2008-04-10 10:09 UTC (permalink / raw
To: Jean Delvare
Cc: Darius, linux-arm-kernel-xIg/pKzrS19vn6HldHNs0ANdhmdF6hFW,
i2c-GZX6beZjE8VD60Wz+7aTrA, Ben Dooks
On Apr 10, 2008, at 5:01 AM, Jean Delvare wrote:
> On Wed, 9 Apr 2008 22:25:39 -0500 (CDT), Kumar Gala wrote:
>>
>> On Thu, 10 Apr 2008, Ben Dooks wrote:
>>
>>> On Tue, Apr 08, 2008 at 11:01:25AM +0300, Darius wrote:
>>>> changes:
>>>> 1. Removed hardcoded constants
>>>> 2. Fixed bug in chip hardware
>>>> 3. Added i2c device for mx1ads
>>>>
>>>> Tested with mx1ads v2.0 board and LCD on I2C interface driver
>>>>
>>>> Signed-off-by: Darius Augulis <augulis.darius-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>>>> ---
>>>
>>> Hmm, this hasn't appeared on the i2c list where it should be being
>>> reviewed before submission. Not bothered to look or snip the rest.
>>
>> looking at this it seems the HW is identical to the driver handled by
>> i2c-mpc.c. (which is used on Motorola and now Freescale PPC chips).
>
> Then I guess that we want to add support to the i2c-mpc driver rather
> than adding another driver to the kernel tree?
that would be my opinion.
- k
_______________________________________________
i2c mailing list
i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org
http://lists.lm-sensors.org/mailman/listinfo/i2c
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3] I2C driver for IMX
2008-04-10 10:01 ` Jean Delvare
[not found] ` <20080410120141.4d220d27-ig7AzVSIIG7kN2dkZ6Wm7A@public.gmane.org>
@ 2008-04-10 10:33 ` Darius
2008-04-10 11:33 ` Juergen Beisert
1 sibling, 1 reply; 11+ messages in thread
From: Darius @ 2008-04-10 10:33 UTC (permalink / raw
To: linux-arm-kernel; +Cc: i2c
Jean Delvare wrote:
> On Wed, 9 Apr 2008 22:25:39 -0500 (CDT), Kumar Gala wrote:
>> On Thu, 10 Apr 2008, Ben Dooks wrote:
>>
>>> On Tue, Apr 08, 2008 at 11:01:25AM +0300, Darius wrote:
>>>> changes:
>>>> 1. Removed hardcoded constants
>>>> 2. Fixed bug in chip hardware
>>>> 3. Added i2c device for mx1ads
>>>>
>>>> Tested with mx1ads v2.0 board and LCD on I2C interface driver
>>>>
>>>> Signed-off-by: Darius Augulis <augulis.darius@gmail.com>
>>>> ---
>>> Hmm, this hasn't appeared on the i2c list where it should be being
>>> reviewed before submission. Not bothered to look or snip the rest.
>> looking at this it seems the HW is identical to the driver handled by
>> i2c-mpc.c. (which is used on Motorola and now Freescale PPC chips).
>
> Then I guess that we want to add support to the i2c-mpc driver rather
> than adding another driver to the kernel tree?
>
I prefer to use separate driver for imx i2c inteface.
if it's not needed for all, I'll leave it for my private needs.
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^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3] I2C driver for IMX
2008-04-10 10:33 ` Darius
@ 2008-04-10 11:33 ` Juergen Beisert
2008-04-10 12:24 ` Russell King - ARM Linux
0 siblings, 1 reply; 11+ messages in thread
From: Juergen Beisert @ 2008-04-10 11:33 UTC (permalink / raw
To: linux-arm-kernel; +Cc: Darius, i2c
On Thursday 10 April 2008 12:33, Darius wrote:
> Jean Delvare wrote:
> > On Wed, 9 Apr 2008 22:25:39 -0500 (CDT), Kumar Gala wrote:
> >> On Thu, 10 Apr 2008, Ben Dooks wrote:
> >>> On Tue, Apr 08, 2008 at 11:01:25AM +0300, Darius wrote:
> >>>> changes:
> >>>> 1. Removed hardcoded constants
> >>>> 2. Fixed bug in chip hardware
> >>>> 3. Added i2c device for mx1ads
> >>>>
> >>>> Tested with mx1ads v2.0 board and LCD on I2C interface driver
> >>>>
> >>>> Signed-off-by: Darius Augulis <augulis.darius@gmail.com>
> >>>> ---
> >>>
> >>> Hmm, this hasn't appeared on the i2c list where it should be being
> >>> reviewed before submission. Not bothered to look or snip the rest.
> >>
> >> looking at this it seems the HW is identical to the driver handled by
> >> i2c-mpc.c. (which is used on Motorola and now Freescale PPC chips).
Same answer as last year.
> > Then I guess that we want to add support to the i2c-mpc driver rather
> > than adding another driver to the kernel tree?
>
> I prefer to use separate driver for imx i2c inteface.
> if it's not needed for all, I'll leave it for my private needs.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
As I did with my imx i2c driver last year....Yes, this I2C controller is
mostly the same than the one in the MPC family and mostly the same the ones
we can find in the MCX family (i.MX21/27, i.MX31?). But it seems there is
noone who is able to write such a generic driver.
Juergen
--
Dipl.-Ing. Juergen Beisert | http://www.pengutronix.de
Pengutronix - Linux Solutions for Science and Industry
Handelsregister: Amtsgericht Hildesheim, HRA 2686
Vertretung Sued/Muenchen, Germany
Phone: +49-8766-939 228 | Fax: +49-5121-206917-9
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^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3] I2C driver for IMX
2008-04-10 11:33 ` Juergen Beisert
@ 2008-04-10 12:24 ` Russell King - ARM Linux
2008-04-10 12:31 ` Darius
0 siblings, 1 reply; 11+ messages in thread
From: Russell King - ARM Linux @ 2008-04-10 12:24 UTC (permalink / raw
To: Juergen Beisert; +Cc: Darius, linux-arm-kernel, i2c
On Thu, Apr 10, 2008 at 01:33:51PM +0200, Juergen Beisert wrote:
> On Thursday 10 April 2008 12:33, Darius wrote:
> > > Then I guess that we want to add support to the i2c-mpc driver rather
> > > than adding another driver to the kernel tree?
> >
> > I prefer to use separate driver for imx i2c inteface.
> > if it's not needed for all, I'll leave it for my private needs.
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> As I did with my imx i2c driver last year....Yes, this I2C controller is
> mostly the same than the one in the MPC family and mostly the same the ones
> we can find in the MCX family (i.MX21/27, i.MX31?). But it seems there is
> noone who is able to write such a generic driver.
Which basically means everyone gets to write their own IMX I2C driver.
What a brilliant advert for open source software. ;(
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^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3] I2C driver for IMX
2008-04-10 12:24 ` Russell King - ARM Linux
@ 2008-04-10 12:31 ` Darius
2008-04-14 0:55 ` Pavel Pisa
0 siblings, 1 reply; 11+ messages in thread
From: Darius @ 2008-04-10 12:31 UTC (permalink / raw
To: linux-arm-kernel; +Cc: i2c
Russell King - ARM Linux wrote:
> On Thu, Apr 10, 2008 at 01:33:51PM +0200, Juergen Beisert wrote:
>> On Thursday 10 April 2008 12:33, Darius wrote:
>>>> Then I guess that we want to add support to the i2c-mpc driver rather
>>>> than adding another driver to the kernel tree?
>>> I prefer to use separate driver for imx i2c inteface.
>>> if it's not needed for all, I'll leave it for my private needs.
>> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>> As I did with my imx i2c driver last year....Yes, this I2C controller is
>> mostly the same than the one in the MPC family and mostly the same the ones
>> we can find in the MCX family (i.MX21/27, i.MX31?). But it seems there is
>> noone who is able to write such a generic driver.
>
> Which basically means everyone gets to write their own IMX I2C driver.
> What a brilliant advert for open source software. ;(
>
why not to submit this my driver into kernel? i2c driver is not so big
fat thing, kernel size will not increase dramatically, even mpc has
similar hardware and similar driver.
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^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3] I2C driver for IMX
2008-04-10 12:31 ` Darius
@ 2008-04-14 0:55 ` Pavel Pisa
0 siblings, 0 replies; 11+ messages in thread
From: Pavel Pisa @ 2008-04-14 0:55 UTC (permalink / raw
To: linux-arm-kernel-xIg/pKzrS19vn6HldHNs0ANdhmdF6hFW
Cc: Darius, i2c-GZX6beZjE8VD60Wz+7aTrA
On Thursday 10 April 2008 14:31, Darius wrote:
> Russell King - ARM Linux wrote:
> > On Thu, Apr 10, 2008 at 01:33:51PM +0200, Juergen Beisert wrote:
> >> On Thursday 10 April 2008 12:33, Darius wrote:
> >>>> Then I guess that we want to add support to the i2c-mpc driver rather
> >>>> than adding another driver to the kernel tree?
> >>>
> >>> I prefer to use separate driver for imx i2c inteface.
> >>> if it's not needed for all, I'll leave it for my private needs.
> >>
> >> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> >> As I did with my imx i2c driver last year....Yes, this I2C controller is
> >> mostly the same than the one in the MPC family and mostly the same the
> >> ones we can find in the MCX family (i.MX21/27, i.MX31?). But it seems
> >> there is noone who is able to write such a generic driver.
> >
> > Which basically means everyone gets to write their own IMX I2C driver.
> > What a brilliant advert for open source software. ;(
>
> why not to submit this my driver into kernel? i2c driver is not so big
> fat thing, kernel size will not increase dramatically, even mpc has
> similar hardware and similar driver.
Hello All,
I agree, that it is better to include this driver than to wait for common
one. If there be even two fully working and tested variants, then it could
be simpler to prepare generic one in future.
I admit that I am the one who noticed similarity of the i.MX and MPC
I2C cores last year but the differences/lack of functionality
of i.MX version makes reuse of MPC one very problematic.
I have tried to contact MPC variant author, but nobody
replied => separate i.MX version is probably the best option
for now.
Best wishes
Pavel
On Friday 10 August 2007 17:15, Pavel Pisa wrote:
....
> The curious information for you could be, that driver for
> I2C core same/similar to one found in i.MX families is
> already included in mainline kernel.
>
> linux-2.6.23-git/drivers/i2c/busses/i2c-mpc.c
>
> It is I2C core for PowerPC MPC5200 chips.
> Unfortunately, the i.MX version lacks
> I2C Interrupt Control Register, which is later
> patch added to MPC5200. It is common to both MPC5200
> I2C interfaces. It provides very wanted feature.
> It allow s to ask for signaling interrupt when bus
> becomes free (BNBE1 and BNBE2 bits). It is paintfully
> missing on i.MX. This means, that probing for bus
> free condition has to be solved by polling timer on MX1.
>
> The other difference is missing bit AKF in Status Register,
> which complicates processing of lost arbitration and
> simultaneous addressed as slave condition.
>
> The less important is missing support for glitches
> filtering configuration register.
>
> I suggest to look at MPC5200 documentation, because
> it is little more comprehensive. The other source
> of documentation Tundra Universe II VME to PCI bridge
> manual, because this chip contains same I2C core too.
>
> I have even written fully interrupt driven driver
> for MX1 for RTEMS executive. It runs in its own thread.
> I have not finished functionality yet, but master works
> reliably. I can send it as other reference.
>
> Generally it would be nice if "i2c-mpc" driver could
> be reuse by i.MX familly. It is better to have not
> two drivers implementations for same IP core.
> But due to lack of BNBEx and other minor differences
> it would require some ifdefs in the source or processing
> altered by core variant flags. The free bus polling
> timer for BNBEx would be required too. So I am not
> sure if something like that is acceptable for PowerPC
> people or if the code should be duplicated.
> I am sending copy to Adrian Cox who seems
> to be author of MPC5200 driver.
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^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3] I2C driver for IMX
2008-04-08 8:01 [PATCH V3] I2C driver for IMX Darius
2008-04-09 23:28 ` Ben Dooks
@ 2008-04-15 11:03 ` Darius
1 sibling, 0 replies; 11+ messages in thread
From: Darius @ 2008-04-15 11:03 UTC (permalink / raw
To: linux-arm-kernel; +Cc: i2c
Added as 4975/1
Darius.
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^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2008-04-15 11:03 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2008-04-08 8:01 [PATCH V3] I2C driver for IMX Darius
2008-04-09 23:28 ` Ben Dooks
[not found] ` <20080409232834.GG1197-SMNkleLxa3Z6Wcw2j4pizdi2O/JbrIOy@public.gmane.org>
2008-04-10 3:25 ` Kumar Gala
2008-04-10 10:01 ` Jean Delvare
[not found] ` <20080410120141.4d220d27-ig7AzVSIIG7kN2dkZ6Wm7A@public.gmane.org>
2008-04-10 10:09 ` Kumar Gala
2008-04-10 10:33 ` Darius
2008-04-10 11:33 ` Juergen Beisert
2008-04-10 12:24 ` Russell King - ARM Linux
2008-04-10 12:31 ` Darius
2008-04-14 0:55 ` Pavel Pisa
2008-04-15 11:03 ` Darius
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