AM3517: Enable I2C-GPIO Expander driver support for AM3517EVM

Add platform hook-up interface to support I2C based GPIo expander
(TCA6416).

There are 3 instances of I2C Expander on AM3517EVM,
	- One is over I2C-2 mounted on Base board
	- Two are over I2C3 mounted on UI Card
Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/board-am3517evm.c

@@ -20,6 +20,7 @@
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/gpio.h>
+#include <linux/i2c/pca953x.h>
 
 #include <mach/hardware.h>
 #include <mach/am35xx.h>
@@ -71,11 +72,46 @@ static void __init am3517_evm_rtc_init(void)
 	am3517evm_i2c_boardinfo[0].irq = gpio_to_irq(GPIO_RTCS35390A_IRQ);
 }
 
+/*
+ * I2C GPIO Expander - TCA6416
+ */
+
+/* Mounted on Base-Board */
+static struct pca953x_platform_data am3517evm_gpio_expander_info_0 = {
+	.gpio_base	= OMAP_MAX_GPIO_LINES,
+};
+static struct i2c_board_info __initdata am3517evm_tca6516_info_0[] = {
+	{
+		I2C_BOARD_INFO("tca6416", 0x21),
+		.platform_data = &am3517evm_gpio_expander_info_0,
+	},
+};
+
+/* Mounted on UI Card */
+static struct pca953x_platform_data am3517evm_ui_gpio_expander_info_1 = {
+	.gpio_base	= OMAP_MAX_GPIO_LINES + 16,
+};
+static struct pca953x_platform_data am3517evm_ui_gpio_expander_info_2 = {
+	.gpio_base	= OMAP_MAX_GPIO_LINES + 32,
+};
+static struct i2c_board_info __initdata am3517evm_ui_tca6516_info[] = {
+	{
+		I2C_BOARD_INFO("tca6416", 0x20),
+		.platform_data = &am3517evm_ui_gpio_expander_info_1,
+	},
+	{
+		I2C_BOARD_INFO("tca6416", 0x21),
+		.platform_data = &am3517evm_ui_gpio_expander_info_2,
+	},
+};
+
 static int __init am3517_evm_i2c_init(void)
 {
 	omap_register_i2c_bus(1, 400, NULL, 0);
-	omap_register_i2c_bus(2, 400, NULL, 0);
-	omap_register_i2c_bus(3, 400, NULL, 0);
+	omap_register_i2c_bus(2, 400, am3517evm_tca6516_info_0,
+			ARRAY_SIZE(am3517evm_tca6516_info_0));
+	omap_register_i2c_bus(3, 400, am3517evm_ui_tca6516_info,
+			ARRAY_SIZE(am3517evm_ui_tca6516_info));
 
 	return 0;
 }