pinctrl: Add STM32 MCUs support

This patch adds pinctrl and GPIO support to STMicroelectronic's STM32
family of MCUs.

While it only supports STM32F429 for now, it has been designed to enable
support of other MCUs of the family (e.g. STM32F746).
Acked-by: NPatrice Chotard <patrice.chotard@st.com>
Signed-off-by: NMaxime Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/Kconfig

@@ -257,6 +257,7 @@ source "drivers/pinctrl/qcom/Kconfig"
 source "drivers/pinctrl/samsung/Kconfig"
 source "drivers/pinctrl/sh-pfc/Kconfig"
 source "drivers/pinctrl/spear/Kconfig"
+source "drivers/pinctrl/stm32/Kconfig"
 source "drivers/pinctrl/sunxi/Kconfig"
 source "drivers/pinctrl/uniphier/Kconfig"
 source "drivers/pinctrl/vt8500/Kconfig"

drivers/pinctrl/Makefile

@@ -51,6 +51,7 @@ obj-$(CONFIG_ARCH_QCOM)		+= qcom/
 obj-$(CONFIG_PINCTRL_SAMSUNG)	+= samsung/
 obj-$(CONFIG_PINCTRL_SH_PFC)	+= sh-pfc/
 obj-$(CONFIG_PINCTRL_SPEAR)	+= spear/
+obj-$(CONFIG_ARCH_STM32)	+= stm32/
 obj-$(CONFIG_ARCH_SUNXI)	+= sunxi/
 obj-$(CONFIG_PINCTRL_UNIPHIER)	+= uniphier/
 obj-$(CONFIG_ARCH_VT8500)	+= vt8500/

drivers/pinctrl/stm32/Kconfig

+if ARCH_STM32 || COMPILE_TEST
+
+config PINCTRL_STM32
+	bool
+	depends on OF
+	select PINMUX
+	select GENERIC_PINCONF
+	select GPIOLIB
+
+config PINCTRL_STM32F429
+	bool "STMicroelectronics STM32F429 pin control" if COMPILE_TEST && !MACH_STM32F429
+	depends on OF
+	default MACH_STM32F429
+	select PINCTRL_STM32
+
+endif

drivers/pinctrl/stm32/Makefile

+# Core
+obj-$(CONFIG_PINCTRL_STM32) += pinctrl-stm32.o
+
+# SoC Drivers
+obj-$(CONFIG_PINCTRL_STM32F429)	+= pinctrl-stm32f429.o

drivers/pinctrl/stm32/pinctrl-stm32.h

+/*
+ * Copyright (C) Maxime Coquelin 2015
+ * Author:  Maxime Coquelin <mcoquelin.stm32@gmail.com>
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+#ifndef __PINCTRL_STM32_H
+#define __PINCTRL_STM32_H
+
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinconf-generic.h>
+
+struct stm32_desc_function {
+	const char *name;
+	const unsigned char num;
+};
+
+struct stm32_desc_pin {
+	struct pinctrl_pin_desc pin;
+	const struct stm32_desc_function *functions;
+};
+
+#define STM32_PIN(_pin, ...)					\
+	{							\
+		.pin = _pin,					\
+		.functions = (struct stm32_desc_function[]){	\
+			__VA_ARGS__, { } },			\
+	}
+
+#define STM32_FUNCTION(_num, _name)		\
+	{							\
+		.num = _num,					\
+		.name = _name,					\
+	}
+
+struct stm32_pinctrl_match_data {
+	const struct stm32_desc_pin *pins;
+	const unsigned int npins;
+};
+
+int stm32_pctl_probe(struct platform_device *pdev);
+
+#endif /* __PINCTRL_STM32_H */
+