drivers: pinctrl: Add pinctrl driver for Microchip PIC32.

In PIC32 pin-controller is a combined gpio-controller, pin-mux and
pin-config module. Remappable peripherals are assigned pins through
per-pin based muxing logic. And pin configuration are performed on
specific port registers which are shared along with gpio controller.
Note, non-remappable peripherals have default pins assigned thus
require no muxing.

Signed-off-by: Purna Chandra Mandal <purna.mandal@microchip.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index 57e6142..5dd2ddd 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -131,6 +131,16 @@
 	  actually does nothing but print debug messages when pinctrl
 	  operations are invoked.
 
+config PIC32_PINCTRL
+	bool "Microchip PIC32 pin-control and pin-mux driver"
+	depends on DM && MACH_PIC32
+	default y
+	help
+	  Supports individual pin selection and configuration for each remappable
+	  peripheral available on Microchip PIC32 SoCs. This driver is controlled
+	  by a device tree node which contains both GPIO defintion and pin control
+	  functions.
+
 endif
 
 source "drivers/pinctrl/uniphier/Kconfig"