i2c: Set SCL pin to gpio functionality before bus recovery

Commit Message

Philby John March 17, 2010, 11:21 a.m. UTC

None

Patch

diff --git a/arch/arm/mach-davinci/board-dm355-evm.c b/arch/arm/mach-davinci/board-dm355-evm.c
index aa48e3f..f4cbf54 100644
--- a/arch/arm/mach-davinci/board-dm355-evm.c
+++ b/arch/arm/mach-davinci/board-dm355-evm.c
@@ -111,7 +111,6 @@  static struct platform_device davinci_nand_device = {
 static struct davinci_i2c_platform_data i2c_pdata = {
 	.bus_freq	= 400	/* kHz */,
 	.bus_delay	= 0	/* usec */,
-	.sda_pin        = 15,
 	.scl_pin        = 14,
 };
 
diff --git a/arch/arm/mach-davinci/board-dm644x-evm.c b/arch/arm/mach-davinci/board-dm644x-evm.c
index 976e11b..19508e3 100644
--- a/arch/arm/mach-davinci/board-dm644x-evm.c
+++ b/arch/arm/mach-davinci/board-dm644x-evm.c
@@ -629,7 +629,6 @@  static struct i2c_board_info __initdata i2c_info[] =  {
 static struct davinci_i2c_platform_data i2c_pdata = {
 	.bus_freq	= 20 /* kHz */,
 	.bus_delay	= 100 /* usec */,
-	.sda_pin        = 44,
 	.scl_pin        = 43,
 };
 
diff --git a/arch/arm/mach-davinci/include/mach/i2c.h b/arch/arm/mach-davinci/include/mach/i2c.h
index 39fdcea..95894ca 100644
--- a/arch/arm/mach-davinci/include/mach/i2c.h
+++ b/arch/arm/mach-davinci/include/mach/i2c.h
@@ -16,8 +16,7 @@ 
 struct davinci_i2c_platform_data {
 	unsigned int	bus_freq;	/* standard bus frequency (kHz) */
 	unsigned int	bus_delay;	/* post-transaction delay (usec) */
-	unsigned int    sda_pin;        /* GPIO pin ID to use for SDA */
-	unsigned int    scl_pin;        /* GPIO pin ID to use for SCL */
+	unsigned int	scl_pin;	/* GPIO pin ID to use for SCL */
 };
 
 /* for board setup code */
diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index 7a28e60..df909e3 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -64,6 +64,7 @@ 
 #define DAVINCI_I2C_IVR_REG	0x28
 #define DAVINCI_I2C_EMDR_REG	0x2c
 #define DAVINCI_I2C_PSC_REG	0x30
+#define DAVINCI_I2C_REVID2_REG	0x38
 
 #define DAVINCI_I2C_IVR_AAS	0x07
 #define DAVINCI_I2C_IVR_SCD	0x06
@@ -133,11 +134,21 @@  static inline u16 davinci_i2c_read_reg(struct davinci_i2c_dev *i2c_dev, int reg)
 }
 
 /* Generate a pulse on the i2c clock pin. */
-static void generic_i2c_clock_pulse(unsigned int scl_pin)
+static void generic_i2c_clock_pulse(unsigned int revid, unsigned int scl_pin)
 {
 	u16 i;
+	int ret;
 
 	if (scl_pin) {
+		if (revid == 0x05) {
+			ret = gpio_request(scl_pin, "SCL Pin\n");
+			if (ret) {
+				pr_warning("gpio request pin %d failed\n",
+					scl_pin);
+				return;
+			}
+			gpio_direction_output(scl_pin, 1);
+		}
 		/* Send high and low on the SCL line */
 		for (i = 0; i < 9; i++) {
 			gpio_set_value(scl_pin, 0);
@@ -162,8 +173,10 @@  static void i2c_recover_bus(struct davinci_i2c_dev *dev)
 	flag |=  DAVINCI_I2C_MDR_NACK;
 	/* write the data into mode register */
 	davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag);
-	if (pdata)
-		generic_i2c_clock_pulse(pdata->scl_pin);
+	if (pdata) {
+		flag = davinci_i2c_read_reg(dev, DAVINCI_I2C_REVID2_REG);
+		generic_i2c_clock_pulse(flag, pdata->scl_pin);
+	}
 	/* Send STOP */
 	flag = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
 	flag |= DAVINCI_I2C_MDR_STP;