i2c: exynos5: add High Speed I2C controller driver

Adds support for High Speed I2C driver found in Exynos5 and
later SoCs from Samsung.

Driver only supports Device Tree method.

Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Signed-off-by: Taekgyun Ko <taeggyun.ko@samsung.com>
Reviewed-by: Simon Glass <sjg@google.com>
Signed-off-by: Yuvaraj Kumar C D <yuvaraj.cd@samsung.com>
Signed-off-by: Andrew Bresticker <abrestic@google.com>
[wsa: rebased to v3.12-rc4 (no of_i2c.h anymore)]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Documentation/devicetree/bindings/i2c/i2c-exynos5.txt

+* Samsung's High Speed I2C controller
+
+The Samsung's High Speed I2C controller is used to interface with I2C devices
+at various speeds ranging from 100khz to 3.4Mhz.
+
+Required properties:
+  - compatible: value should be.
+      -> "samsung,exynos5-hsi2c", for i2c compatible with exynos5 hsi2c.
+  - reg: physical base address of the controller and length of memory mapped
+    region.
+  - interrupts: interrupt number to the cpu.
+  - #address-cells: always 1 (for i2c addresses)
+  - #size-cells: always 0
+
+  - Pinctrl:
+    - pinctrl-0: Pin control group to be used for this controller.
+    - pinctrl-names: Should contain only one value - "default".
+
+Optional properties:
+  - clock-frequency: Desired operating frequency in Hz of the bus.
+    -> If not specified, the bus operates in fast-speed mode at
+       at 100khz.
+    -> If specified, the bus operates in high-speed mode only if the
+       clock-frequency is >= 1Mhz.
+
+Example:
+
+hsi2c@12ca0000 {
+	compatible = "samsung,exynos5-hsi2c";
+	reg = <0x12ca0000 0x100>;
+	interrupts = <56>;
+	clock-frequency = <100000>;
+
+	pinctrl-0 = <&i2c4_bus>;
+	pinctrl-names = "default";
+
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	s2mps11_pmic@66 {
+		compatible = "samsung,s2mps11-pmic";
+		reg = <0x66>;
+	};
+};

drivers/i2c/busses/Kconfig

@@ -436,6 +436,13 @@ config I2C_EG20T
 	  ML7213/ML7223/ML7831 is companion chip for Intel Atom E6xx series.
 	  ML7213/ML7223/ML7831 is completely compatible for Intel EG20T PCH.
 
+config I2C_EXYNOS5
+	tristate "Exynos5 high-speed I2C driver"
+	depends on ARCH_EXYNOS5 && OF
+	help
+	  Say Y here to include support for high-speed I2C controller in the
+	  Exynos5 based Samsung SoCs.
+
 config I2C_GPIO
 	tristate "GPIO-based bitbanging I2C"
 	depends on GPIOLIB

drivers/i2c/busses/Makefile

@@ -42,6 +42,7 @@ i2c-designware-platform-objs := i2c-designware-platdrv.o
 obj-$(CONFIG_I2C_DESIGNWARE_PCI)	+= i2c-designware-pci.o
 i2c-designware-pci-objs := i2c-designware-pcidrv.o
 obj-$(CONFIG_I2C_EG20T)		+= i2c-eg20t.o
+obj-$(CONFIG_I2C_EXYNOS5)	+= i2c-exynos5.o
 obj-$(CONFIG_I2C_GPIO)		+= i2c-gpio.o
 obj-$(CONFIG_I2C_HIGHLANDER)	+= i2c-highlander.o
 obj-$(CONFIG_I2C_IBM_IIC)	+= i2c-ibm_iic.o