gpio/rockchip: add driver for rockchip gpio

This patch add support for rockchip gpio controller, which is supported
in pinctrl driver in the past.

With this patch, the pinctrl-rockchip driver will drop gpio related
codes and populate platform driver to gpio-rockchip.

Signed-off-by: Jianqun Xu <jay.xu@rock-chips.com>
Link: https://lore.kernel.org/r/20210816012053.1119069-1-jay.xu@rock-chips.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/Kconfig

@@ -520,6 +520,14 @@ config GPIO_REG
 	  A 32-bit single register GPIO fixed in/out implementation.  This
 	  can be used to represent any register as a set of GPIO signals.
 
+config GPIO_ROCKCHIP
+	tristate "Rockchip GPIO support"
+	depends on ARCH_ROCKCHIP || COMPILE_TEST
+	select GPIOLIB_IRQCHIP
+	default ARCH_ROCKCHIP
+	help
+	  Say yes here to support GPIO on Rockchip SoCs.
+
 config GPIO_SAMA5D2_PIOBU
 	tristate "SAMA5D2 PIOBU GPIO support"
 	depends on MFD_SYSCON

drivers/gpio/Makefile

@@ -128,6 +128,7 @@ obj-$(CONFIG_GPIO_RDA)			+= gpio-rda.o
 obj-$(CONFIG_GPIO_RDC321X)		+= gpio-rdc321x.o
 obj-$(CONFIG_GPIO_REALTEK_OTTO)		+= gpio-realtek-otto.o
 obj-$(CONFIG_GPIO_REG)			+= gpio-reg.o
+obj-$(CONFIG_GPIO_ROCKCHIP)	+= gpio-rockchip.o
 obj-$(CONFIG_ARCH_SA1100)		+= gpio-sa1100.o
 obj-$(CONFIG_GPIO_SAMA5D2_PIOBU)	+= gpio-sama5d2-piobu.o
 obj-$(CONFIG_GPIO_SCH311X)		+= gpio-sch311x.o