[PATCH 2/3] ARM: AM33xx: Add i2c support for AM33xx

[Teresa Gámez]

Added device register functions and cpu_is_am33xx()
function.
Adapted the i2c-omap driver. AM335x has a lower
clock rate and the timeout of polling the isr function
had to be increased.

Based on a patch from Shravan Kumar <shravan.k at phytec.in>.

Signed-off-by: Teresa Gámez <t.gamez at phytec.de>
---
 arch/arm/mach-omap/include/mach/am33xx-devices.h |   15 +++++++++++++++
 arch/arm/mach-omap/include/mach/am33xx-silicon.h |    5 +++++
 arch/arm/mach-omap/include/mach/generic.h        |    6 ++++++
 drivers/i2c/busses/i2c-omap.c                    |   14 +++++++++-----
 4 files changed, 35 insertions(+), 5 deletions(-)

diff --git a/arch/arm/mach-omap/include/mach/am33xx-devices.h b/arch/arm/mach-omap/include/mach/am33xx-devices.h
index 7da4b99..822caab 100644
--- a/arch/arm/mach-omap/include/mach/am33xx-devices.h
+++ b/arch/arm/mach-omap/include/mach/am33xx-devices.h
@@ -53,4 +53,19 @@ static inline struct device_d *am33xx_add_spi1(void)
 	return am33xx_add_spi(1, AM33XX_MCSPI1_BASE);
 }
 
+static inline struct device_d *am33xx_add_i2c0(void *pdata)
+{
+	return omap_add_i2c(0, AM33XX_I2C0_BASE, pdata);
+}
+
+static inline struct device_d *am33xx_add_i2c1(void *pdata)
+{
+	return omap_add_i2c(1, AM33XX_I2C1_BASE, pdata);
+}
+
+static inline struct device_d *am33xx_add_i2c2(void *pdata)
+{
+	return omap_add_i2c(2, AM33XX_I2C2_BASE, pdata);
+}
+
 #endif /* __MACH_OMAP3_DEVICES_H */
diff --git a/arch/arm/mach-omap/include/mach/am33xx-silicon.h b/arch/arm/mach-omap/include/mach/am33xx-silicon.h
index 59284af..8a7bd16 100644
--- a/arch/arm/mach-omap/include/mach/am33xx-silicon.h
+++ b/arch/arm/mach-omap/include/mach/am33xx-silicon.h
@@ -41,6 +41,11 @@
 #define AM33XX_DRAM_ADDR_SPACE_START	0x80000000
 #define AM33XX_DRAM_ADDR_SPACE_END	0xC0000000
 
+/* I2C */
+#define AM33XX_I2C0_BASE	(AM33XX_L4_WKUP_BASE + 0x20B000)
+#define AM33XX_I2C1_BASE	(AM33XX_L4_PER_BASE + 0x02A000)
+#define AM33XX_I2C2_BASE	(AM33XX_L4_PER_BASE + 0x19C000)
+
 /* GPMC */
 #define AM33XX_GPMC_BASE		0x50000000
 
diff --git a/arch/arm/mach-omap/include/mach/generic.h b/arch/arm/mach-omap/include/mach/generic.h
index 5a10a54..178c21f 100644
--- a/arch/arm/mach-omap/include/mach/generic.h
+++ b/arch/arm/mach-omap/include/mach/generic.h
@@ -27,4 +27,10 @@
 #define cpu_is_omap4xxx()	(0)
 #endif
 
+#ifdef CONFIG_ARCH_AM33XX
+#define cpu_is_am33xx()		(1)
+#else
+#define cpu_is_am33xx()		(0)
+#endif
+
 #endif
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index ecb33ea..19d54ee 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -245,7 +245,7 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_struct *i2c_omap, int reg)
 
 static void omap_i2c_unidle(struct omap_i2c_struct *i2c_omap)
 {
-	if (cpu_is_omap34xx()) {
+	if (cpu_is_omap34xx() || cpu_is_am33xx()) {
 		omap_i2c_write_reg(i2c_omap, OMAP_I2C_CON_REG, 0);
 		omap_i2c_write_reg(i2c_omap, OMAP_I2C_PSC_REG, i2c_omap->pscstate);
 		omap_i2c_write_reg(i2c_omap, OMAP_I2C_SCLL_REG, i2c_omap->scllstate);
@@ -353,7 +353,11 @@ static int omap_i2c_init(struct omap_i2c_struct *i2c_omap)
 		internal_clk = 9600;
 	else
 		internal_clk = 4000;
-	fclk_rate = 96000000 / 1000;
+
+	if (cpu_is_am33xx())
+		fclk_rate = 48000;
+	else
+		fclk_rate = 96000;
 
 	/* Compute prescaler divisor */
 	psc = fclk_rate / internal_clk;
@@ -410,7 +414,7 @@ static int omap_i2c_init(struct omap_i2c_struct *i2c_omap)
 			OMAP_I2C_IE_AL)  | ((i2c_omap->fifo_size) ?
 				(OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
 	omap_i2c_write_reg(i2c_omap, OMAP_I2C_IE_REG, i2c_omap->iestate);
-	if (cpu_is_omap34xx()) {
+	if (cpu_is_omap34xx() || cpu_is_am33xx()) {
 		i2c_omap->pscstate = psc;
 		i2c_omap->scllstate = scll;
 		i2c_omap->sclhstate = sclh;
@@ -665,7 +669,7 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adapter,
 	ret = omap_i2c_isr(i2c_omap);
 	while (ret){
 		ret = omap_i2c_isr(i2c_omap);
-		if (is_timeout(start, MSECOND)) {
+		if (is_timeout(start, 50 * MSECOND)) {
 				dev_err(&adapter->dev,
 				"timed out on polling for "
 				"open i2c message handling\n");
@@ -743,7 +747,7 @@ i2c_omap_probe(struct device_d *pdev)
 		goto err_free_mem;
 	}
 
-	if (cpu_is_omap4xxx()) {
+	if (cpu_is_omap4xxx() || cpu_is_am33xx()) {
 		i2c_omap->regs = (u8 *)omap4_reg_map;
 		i2c_omap->reg_shift = 0;
 	} else {
-- 
1.7.0.4