pinctrl: add a pincontrol driver for BCM6318

Add a pincontrol driver for BCM6318. BCM6318 allows muxing most GPIOs
to different functions. BCM6318 is similar to BCM6328 with the addition
of a pad register, and the GPIO meaning of the mux register changes
based on the GPIO number.
Co-developed-by: Jonas Gorski <jonas.gorski@gmail.com>
Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Link: https://lore.kernel.org/r/20210324081923.20379-23-noltari@gmail.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/bcm/Kconfig

@@ -36,6 +36,14 @@ config PINCTRL_BCM63XX
 	select PINCONF
 	select PINMUX
 
+config PINCTRL_BCM6318
+	bool "Broadcom BCM6318 GPIO driver"
+	depends on (BMIPS_GENERIC || COMPILE_TEST)
+	select PINCTRL_BCM63XX
+	default BMIPS_GENERIC
+	help
+	   Say Y here to enable the Broadcom BCM6318 GPIO driver.
+
 config PINCTRL_BCM6328
 	bool "Broadcom BCM6328 GPIO driver"
 	depends on (BMIPS_GENERIC || COMPILE_TEST)

drivers/pinctrl/bcm/Makefile

@@ -4,6 +4,7 @@
 obj-$(CONFIG_PINCTRL_BCM281XX)		+= pinctrl-bcm281xx.o
 obj-$(CONFIG_PINCTRL_BCM2835)		+= pinctrl-bcm2835.o
 obj-$(CONFIG_PINCTRL_BCM63XX)		+= pinctrl-bcm63xx.o
+obj-$(CONFIG_PINCTRL_BCM6318)		+= pinctrl-bcm6318.o
 obj-$(CONFIG_PINCTRL_BCM6328)		+= pinctrl-bcm6328.o
 obj-$(CONFIG_PINCTRL_BCM6358)		+= pinctrl-bcm6358.o
 obj-$(CONFIG_PINCTRL_BCM6362)		+= pinctrl-bcm6362.o