i2c: brcmstb: Add Broadcom settop SoC i2c controller driver

Adding support for i2c controller driver for Broadcom settop
SoCs.
Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
[wsa: removed superfluous owner in platform_driver]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

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

+Broadcom stb bsc iic master controller
+
+Required properties:
+
+- compatible: should be "brcm,brcmstb-i2c"
+- clock-frequency: 32-bit decimal value of iic master clock freqency in Hz
+		   valid values are 375000, 390000, 187500, 200000
+		   93750, 97500, 46875 and 50000
+- reg: specifies the base physical address and size of the registers
+
+Optional properties :
+
+- interrupt-parent: specifies the phandle to the parent interrupt controller
+  this one is cascaded from
+- interrupts: specifies the interrupt number, the irq line to be used
+- interrupt-names: Interrupt name string
+
+Example:
+
+bsca: i2c@f0406200 {
+      clock-frequency = <390000>;
+      compatible = "brcm,brcmstb-i2c";
+      interrupt-parent = <&irq0_intc>;
+      reg = <0xf0406200 0x58>;
+      interrupts = <0x18>;
+      interrupt-names = "upg_bsca";
+};
+

drivers/i2c/busses/Kconfig

@@ -392,6 +392,16 @@ config I2C_BCM_KONA
 
 	  If you do not need KONA I2C interface, say N.
 
+config I2C_BRCMSTB
+	tristate "BRCM Settop I2C controller"
+	depends on ARCH_BRCMSTB || COMPILE_TEST
+	default y
+	help
+	  If you say yes to this option, support will be included for the
+	  I2C interface on the Broadcom Settop SoCs.
+
+	  If you do not need I2C interface, say N.
+
 config I2C_BLACKFIN_TWI
 	tristate "Blackfin TWI I2C support"
 	depends on BLACKFIN

drivers/i2c/busses/Makefile

@@ -106,6 +106,7 @@ obj-$(CONFIG_I2C_VIPERBOARD)	+= i2c-viperboard.o
 # Other I2C/SMBus bus drivers
 obj-$(CONFIG_I2C_ACORN)		+= i2c-acorn.o
 obj-$(CONFIG_I2C_BCM_KONA)	+= i2c-bcm-kona.o
+obj-$(CONFIG_I2C_BRCMSTB)	+= i2c-brcmstb.o
 obj-$(CONFIG_I2C_CROS_EC_TUNNEL)	+= i2c-cros-ec-tunnel.o
 obj-$(CONFIG_I2C_ELEKTOR)	+= i2c-elektor.o
 obj-$(CONFIG_I2C_OPAL)		+= i2c-opal.o