pincntrl: add support for ams AS3722 pin control driver

The AS3722 is a compact system PMU suitable for mobile phones, tablets etc.

Add a driver to support accessing the GPIO, pinmux and pin configuration
of 8 GPIO pins found on the ams AS3722 through pin control driver and
gpiolib.

The driver will register itself as the pincontrol driver and gpio driver.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index 21db201..85f5462 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -59,6 +59,17 @@
 	  future processors. This option is selected automatically when specific
 	  machine and arch are selected to build.
 
+config PINCTRL_AS3722
+	bool "Pinctrl and GPIO driver for ams AS3722 PMIC"
+	depends on MFD_AS3722 && GPIOLIB
+	select PINMUX
+	select GENERIC_PINCONF
+	help
+	  AS3722 device supports the configuration of GPIO pins for different
+	  functionality. This driver supports the pinmux, push-pull and
+	  open drain configuration for the GPIO pins of AS3722 devices. It also
+	  supports the GPIO functionality through gpiolib.
+
 config PINCTRL_BF54x
 	def_bool y if BF54x
 	select PINCTRL_ADI2