i2c: Add driver for Cadence I2C controller

Add a driver for the Cadence I2C controller. This controller is for
example found in Xilinx Zynq.
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

MAINTAINERS

@@ -1402,6 +1402,7 @@ F:	drivers/cpuidle/cpuidle-zynq.c
 N:	zynq
 N:	xilinx
 F:	drivers/clocksource/cadence_ttc_timer.c
+F:	drivers/i2c/busses/i2c-cadence.c
 F:	drivers/mmc/host/sdhci-of-arasan.c
 
 ARM SMMU DRIVER

drivers/i2c/busses/Kconfig

@@ -376,6 +376,13 @@ config I2C_BLACKFIN_TWI_CLK_KHZ
 	help
 	  The unit of the TWI clock is kHz.
 
+config I2C_CADENCE
+	tristate "Cadence I2C Controller"
+	depends on COMMON_CLK
+	help
+	  Say yes here to select Cadence I2C Host Controller. This controller is
+	  e.g. used by Xilinx Zynq.
+
 config I2C_CBUS_GPIO
 	tristate "CBUS I2C driver"
 	depends on GPIOLIB

drivers/i2c/busses/Makefile

@@ -33,6 +33,7 @@ obj-$(CONFIG_I2C_AT91)		+= i2c-at91.o
 obj-$(CONFIG_I2C_AU1550)	+= i2c-au1550.o
 obj-$(CONFIG_I2C_BCM2835)	+= i2c-bcm2835.o
 obj-$(CONFIG_I2C_BLACKFIN_TWI)	+= i2c-bfin-twi.o
+obj-$(CONFIG_I2C_CADENCE)	+= i2c-cadence.o
 obj-$(CONFIG_I2C_CBUS_GPIO)	+= i2c-cbus-gpio.o
 obj-$(CONFIG_I2C_CPM)		+= i2c-cpm.o
 obj-$(CONFIG_I2C_DAVINCI)	+= i2c-davinci.o