i2c: octeon_i2c: Add I2C controller driver for Octeon

Add support for I2C controllers found on Octeon II/III and Octeon TX
TX2 SoC platforms.
Signed-off-by: NAaron Williams <awilliams@marvell.com>
Signed-off-by: NSuneel Garapati <sgarapati@marvell.com>
Signed-off-by: NStefan Roese <sr@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Aaron Williams <awilliams@marvell.com>
Cc: Chandrakala Chavva <cchavva@marvell.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NHeiko Schocher <hs@denx.de>
Reviewed-by: NRayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>

doc/device-tree-bindings/i2c/octeon-i2c.txt

+* I2C controller embedded in Marvell Octeon platforms
+
+Required properties :
+- compatible : Must be "cavium,octeon-7890-twsi" or a compatible string
+- reg : Offset and length of the register set for the device
+- clocks: Must contain the input clock of the I2C instance
+- #address-cells = <1>;
+- #size-cells = <0>;
+
+Optional properties :
+- clock-frequency : Desired I2C bus clock frequency in Hz. If not specified,
+  the default 100 kHz frequency will be used. As only Normal, Fast and Fast+
+  modes are implemented, possible values are 100000, 400000 and 1000000.
+
+Example :
+
+	i2c0: i2c@1180000001000 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		compatible = "cavium,octeon-7890-twsi";
+		reg = <0x11800 0x00001000 0x0 0x200>;
+		clock-frequency = <100000>;
+		clocks = <&sclk>;
+	};

drivers/i2c/Kconfig

@@ -374,6 +374,16 @@ config SYS_I2C_SANDBOX
 	  bus. Devices can be attached to the bus using the device tree
 	  which specifies the driver to use.  See sandbox.dts as an example.
 
+config SYS_I2C_OCTEON
+	bool "Octeon II/III/TX/TX2 I2C driver"
+	depends on (ARCH_OCTEON || ARCH_OCTEONTX || ARCH_OCTEONTX2) && DM_I2C
+	default y
+	help
+	  Add support for the Marvell Octeon I2C driver. This is used with
+	  various Octeon parts such as Octeon II/III and OcteonTX/TX2. All
+	  chips have several I2C ports and all are provided, controlled by
+	  the device tree.
+
 config SYS_I2C_S3C24X0
 	bool "Samsung I2C driver"
 	depends on ARCH_EXYNOS4 && DM_I2C

drivers/i2c/Makefile

@@ -27,6 +27,7 @@ obj-$(CONFIG_SYS_I2C_LPC32XX) += lpc32xx_i2c.o
 obj-$(CONFIG_SYS_I2C_MESON) += meson_i2c.o
 obj-$(CONFIG_SYS_I2C_MVTWSI) += mvtwsi.o
 obj-$(CONFIG_SYS_I2C_MXC) += mxc_i2c.o
+obj-$(CONFIG_SYS_I2C_OCTEON) += octeon_i2c.o
 obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
 obj-$(CONFIG_SYS_I2C_RCAR_I2C) += rcar_i2c.o
 obj-$(CONFIG_SYS_I2C_RCAR_IIC) += rcar_iic.o