pinctrl: Add pincontrol driver for ARTPEC-6 SoC

Add pinctrl driver support for the Axis ARTPEC-6 SoC.
There are only some pins that actually have different
functions available, but all can control bias (pull-up/-down)
and drive strength.

Code originally written by Chris Paterson.

Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index 8f8c2af..37af5e3 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -41,6 +41,17 @@
 	  future processors. This option is selected automatically when specific
 	  machine and arch are selected to build.
 
+config PINCTRL_ARTPEC6
+        bool "Axis ARTPEC-6 pin controller driver"
+        depends on MACH_ARTPEC6
+        select PINMUX
+        select GENERIC_PINCONF
+        help
+          This is the driver for the Axis ARTPEC-6 pin controller. This driver
+          supports pin function multiplexing as well as pin bias and drive
+          strength configuration. Device tree integration instructions can be
+          found in Documentation/devicetree/bindings/pinctrl/axis,artpec6-pinctrl.txt
+
 config PINCTRL_AS3722
 	tristate "Pinctrl and GPIO driver for ams AS3722 PMIC"
 	depends on MFD_AS3722 && GPIOLIB