pinctrl: Add SX150X GPIO Extender Pinctrl Driver

Since the I2C sx150x GPIO expander driver uses platform_data to manage
the pins configurations, rewrite the driver as a pinctrl driver using
pinconf to get/set pin configurations from DT or debugfs.

The pinctrl driver is functionnally equivalent as the gpio-only driver
and can use DT for pinconf. The platform_data confirmation is dropped.

This patchset removed the gpio-only driver and selects the Pinctrl driver
config instead. This patchset also migrates the gpio dt-bindings to pinctrl
and add the pinctrl optional properties.

The driver was tested with a SX1509 device on a BeagleBone black with
interrupt support and on an X86_64 machine over an I2C to USB converter.

This is a fixed version that builds and runs on non-OF platforms and on
arm based OF. The GPIO version is removed and the bindings are also moved
to the pinctrl bindings.

Changes since v2
 - rebased on v4.9-rc1
 - removed MODULE_DEVICE_TABLE as in upstream bb411e77
   ("gpio: sx150x: fix implicit assumption module.h is present")

Changes since v1
 - Fix Kconfig descriptions on pinctrl and gpio
 - Fix Kconfig dependency
 - Remove oscio support for non-789 devices
 - correct typo in dt bindings
 - remove probe reset for non-789 devices

Changes since RFC
 - Put #ifdef CONFIG_OF/CONFIG_OF_GPIO to remove OF code for non-of platforms
 - No more rely on OF_GPIO config
 - Moved and enhanced bindings to pinctrl bindings
 - Removed gpio-sx150x.c
 - Temporary select PINCTRL_SX150X when GPIO_SX150X
 - Temporary mark GPIO_SX150X as deprecated
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Tested-by: Peter Rosin <peda@axentia.se>
Acked-by: Rob Herring <robh@kernel.org>
ested-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Documentation/devicetree/bindings/gpio/gpio-sx150x.txt → Documentation/devicetree/bindings/pinctrl/pinctrl-sx150x.txt

 SEMTECH SX150x GPIO expander bindings
 
+Please refer to pinctrl-bindings.txt, ../gpio/gpio.txt, and
+../interrupt-controller/interrupts.txt for generic information regarding
+pin controller, GPIO, and interrupt bindings.
 
 Required properties:
-
-- compatible: should be "semtech,sx1506q",
+- compatible: should be one of :
+			"semtech,sx1506q",
 			"semtech,sx1508q",
 			"semtech,sx1509q",
 			"semtech,sx1502q".
 
 - reg: The I2C slave address for this device.
 
-- interrupt-parent: phandle of the parent interrupt controller.
-
-- interrupts: Interrupt specifier for the controllers interrupt.
-
 - #gpio-cells: Should be 2. The first cell is the GPIO number and the
 		second cell is used to specify optional parameters:
 		bit 0: polarity (0: normal, 1: inverted)
 
 - gpio-controller: Marks the device as a GPIO controller.
 
+Optional properties :
+- interrupt-parent: phandle of the parent interrupt controller.
+
+- interrupts: Interrupt specifier for the controllers interrupt.
+
 - interrupt-controller: Marks the device as a interrupt controller.
 
+- semtech,probe-reset: Will trigger a reset of the GPIO expander on probe,
+		only for sx1508q and sx1509q
+
 The GPIO expander can optionally be used as an interrupt controller, in
-which case it uses the default two cell specifier as described in
-Documentation/devicetree/bindings/interrupt-controller/interrupts.txt.
+which case it uses the default two cell specifier.
+
+Required properties for pin configuration sub-nodes:
+ - pins: List of pins to which the configuration applies.
+
+Optional properties for pin configuration sub-nodes:
+----------------------------------------------------
+ - bias-disable: disable any pin bias, except the OSCIO pin
+ - bias-pull-up: pull up the pin, except the OSCIO pin
+ - bias-pull-down: pull down the pin, except the OSCIO pin
+ - bias-pull-pin-default: use pin-default pull state, except the OSCIO pin
+ - drive-push-pull: drive actively high and low
+ - drive-open-drain: drive with open drain only for sx1508q and sx1509q and except the OSCIO pin
+ - output-low: set the pin to output mode with low level
+ - output-high: set the pin to output mode with high level
 
 Example:
 
-	i2c_gpio_expander@20{
+	i2c0gpio-expander@20{
 		#gpio-cells = <2>;
 		#interrupt-cells = <2>;
 		compatible = "semtech,sx1506q";
@@ -38,4 +58,12 @@ Example:
 
 		gpio-controller;
 		interrupt-controller;
+
+		pinctrl-names = "default";
+		pinctrl-0 = <&gpio1_cfg_pins>;
+
+		gpio1_cfg_pins: gpio1-cfg {
+			pins = "gpio1";
+			bias-pull-up;
+		};
 	};

drivers/gpio/Kconfig

@@ -781,16 +781,13 @@ config GPIO_PCF857X
 	  platform-neutral GPIO calls.
 
 config GPIO_SX150X
-	bool "Semtech SX150x I2C GPIO expander"
-	depends on I2C=y
-	select GPIOLIB_IRQCHIP
+	bool "Semtech SX150x I2C GPIO expander (deprecated)"
+	depends on PINCTRL && I2C=y
+	select PINCTRL_SX150X
 	default n
 	help
-	  Say yes here to provide support for Semtech SX150-series I2C
-	  GPIO expanders. Compatible models include:
-
-	  8 bits:  sx1508q
-	  16 bits: sx1509q
+	  Say yes here to provide support for Semtech SX150x-series I2C
+	  GPIO expanders. The GPIO driver was replaced by a Pinctrl version.
 
 config GPIO_TPIC2810
 	tristate "TPIC2810 8-Bit I2C GPO expander"

drivers/gpio/Makefile

@@ -102,7 +102,6 @@ obj-$(CONFIG_GPIO_SPEAR_SPICS)	+= gpio-spear-spics.o
 obj-$(CONFIG_GPIO_STA2X11)	+= gpio-sta2x11.o
 obj-$(CONFIG_GPIO_STMPE)	+= gpio-stmpe.o
 obj-$(CONFIG_GPIO_STP_XWAY)	+= gpio-stp-xway.o
-obj-$(CONFIG_GPIO_SX150X)	+= gpio-sx150x.o
 obj-$(CONFIG_GPIO_SYSCON)	+= gpio-syscon.o
 obj-$(CONFIG_GPIO_TB10X)	+= gpio-tb10x.o
 obj-$(CONFIG_GPIO_TC3589X)	+= gpio-tc3589x.o

drivers/pinctrl/Kconfig

@@ -164,6 +164,20 @@ config PINCTRL_SIRF
 	select GENERIC_PINCONF
 	select GPIOLIB_IRQCHIP
 
+config PINCTRL_SX150X
+	bool "Semtech SX150x I2C GPIO expander pinctrl driver"
+	depends on GPIOLIB && I2C=y
+	select PINMUX
+	select PINCONF
+	select GENERIC_PINCONF
+	select GPIOLIB_IRQCHIP
+	help
+	  Say yes here to provide support for Semtech SX150x-series I2C
+	  GPIO expanders as pinctrl module.
+	  Compatible models include:
+	  - 8 bits:  sx1508q, sx1502q
+	  - 16 bits: sx1509q, sx1506q
+
 config PINCTRL_PISTACHIO
 	def_bool y if MACH_PISTACHIO
 	depends on GPIOLIB

drivers/pinctrl/Makefile

@@ -25,6 +25,7 @@ obj-$(CONFIG_PINCTRL_PISTACHIO)	+= pinctrl-pistachio.o
 obj-$(CONFIG_PINCTRL_ROCKCHIP)	+= pinctrl-rockchip.o
 obj-$(CONFIG_PINCTRL_SINGLE)	+= pinctrl-single.o
 obj-$(CONFIG_PINCTRL_SIRF)	+= sirf/
+obj-$(CONFIG_PINCTRL_SX150X)	+= pinctrl-sx150x.o
 obj-$(CONFIG_ARCH_TEGRA)	+= tegra/
 obj-$(CONFIG_PINCTRL_TZ1090)	+= pinctrl-tz1090.o
 obj-$(CONFIG_PINCTRL_TZ1090_PDC)	+= pinctrl-tz1090-pdc.o