pinctrl: move gpio-axp209 to pinctrl

To prepare the driver for the upcoming pinctrl features, move the GPIO
driver AXP209 from GPIO to pinctrl subsystem.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

3 files changed, 200 insertions, 0 deletions

diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index 4571cc098b76..ce126955212c 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -63,6 +63,16 @@ config PINCTRL_AS3722
 	  open drain configuration for the GPIO pins of AS3722 devices. It also
 	  supports the GPIO functionality through gpiolib.
 
+config PINCTRL_AXP209
+	tristate "X-Powers AXP209 PMIC pinctrl and GPIO Support"
+	depends on MFD_AXP20X
+	help
+	  AXP PMICs provides multiple GPIOs that can be muxed for different
+	  functions. This driver bundles a pinctrl driver to select the function
+	  muxing and a GPIO driver to handle the GPIO when the GPIO function is
+	  selected.
+	  Say yes to enable pinctrl and GPIO support for the AXP209 PMIC
+
 config PINCTRL_BF54x
 	def_bool y if BF54x
 	select PINCTRL_ADI2
diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
index d0d4844f8022..4777f1595ce2 100644
--- a/drivers/pinctrl/Makefile
+++ b/drivers/pinctrl/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_GENERIC_PINCONF)	+= pinconf-generic.o
 obj-$(CONFIG_PINCTRL_ADI2)	+= pinctrl-adi2.o
 obj-$(CONFIG_PINCTRL_ARTPEC6)	+= pinctrl-artpec6.o
 obj-$(CONFIG_PINCTRL_AS3722)	+= pinctrl-as3722.o
+obj-$(CONFIG_PINCTRL_AXP209)	+= pinctrl-axp209.o
 obj-$(CONFIG_PINCTRL_BF54x)	+= pinctrl-adi2-bf54x.o
 obj-$(CONFIG_PINCTRL_BF60x)	+= pinctrl-adi2-bf60x.o
 obj-$(CONFIG_PINCTRL_AT91)	+= pinctrl-at91.o
diff --git a/drivers/pinctrl/pinctrl-axp209.c b/drivers/pinctrl/pinctrl-axp209.c
new file mode 100644
index 000000000000..6ee7dc1418fa
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-axp209.c
@@ -0,0 +1,189 @@
+/*
+ * AXP20x GPIO driver
+ *
+ * Copyright (C) 2016 Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under  the terms of the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/gpio/driver.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mfd/axp20x.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#define AXP20X_GPIO_FUNCTIONS		0x7
+#define AXP20X_GPIO_FUNCTION_OUT_LOW	0
+#define AXP20X_GPIO_FUNCTION_OUT_HIGH	1
+#define AXP20X_GPIO_FUNCTION_INPUT	2
+
+struct axp20x_gpio {
+	struct gpio_chip	chip;
+	struct regmap		*regmap;
+};
+
+static int axp20x_gpio_get_reg(unsigned int offset)
+{
+	switch (offset) {
+	case 0:
+		return AXP20X_GPIO0_CTRL;
+	case 1:
+		return AXP20X_GPIO1_CTRL;
+	case 2:
+		return AXP20X_GPIO2_CTRL;
+	}
+
+	return -EINVAL;
+}
+
+static int axp20x_gpio_input(struct gpio_chip *chip, unsigned int offset)
+{
+	struct axp20x_gpio *gpio = gpiochip_get_data(chip);
+	int reg;
+
+	reg = axp20x_gpio_get_reg(offset);
+	if (reg < 0)
+		return reg;
+
+	return regmap_update_bits(gpio->regmap, reg,
+				  AXP20X_GPIO_FUNCTIONS,
+				  AXP20X_GPIO_FUNCTION_INPUT);
+}
+
+static int axp20x_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+	struct axp20x_gpio *gpio = gpiochip_get_data(chip);
+	unsigned int val;
+	int ret;
+
+	ret = regmap_read(gpio->regmap, AXP20X_GPIO20_SS, &val);
+	if (ret)
+		return ret;
+
+	return !!(val & BIT(offset + 4));
+}
+
+static int axp20x_gpio_get_direction(struct gpio_chip *chip,
+				     unsigned int offset)
+{
+	struct axp20x_gpio *gpio = gpiochip_get_data(chip);
+	unsigned int val;
+	int reg, ret;
+
+	reg = axp20x_gpio_get_reg(offset);
+	if (reg < 0)
+		return reg;
+
+	ret = regmap_read(gpio->regmap, reg, &val);
+	if (ret)
+		return ret;
+
+	/*
+	 * This shouldn't really happen if the pin is in use already,
+	 * or if it's not in use yet, it doesn't matter since we're
+	 * going to change the value soon anyway. Default to output.
+	 */
+	if ((val & AXP20X_GPIO_FUNCTIONS) > 2)
+		return 0;
+
+	/*
+	 * The GPIO directions are the three lowest values.
+	 * 2 is input, 0 and 1 are output
+	 */
+	return val & 2;
+}
+
+static int axp20x_gpio_output(struct gpio_chip *chip, unsigned int offset,
+			      int value)
+{
+	struct axp20x_gpio *gpio = gpiochip_get_data(chip);
+	int reg;
+
+	reg = axp20x_gpio_get_reg(offset);
+	if (reg < 0)
+		return reg;
+
+	return regmap_update_bits(gpio->regmap, reg,
+				  AXP20X_GPIO_FUNCTIONS,
+				  value ? AXP20X_GPIO_FUNCTION_OUT_HIGH
+				  : AXP20X_GPIO_FUNCTION_OUT_LOW);
+}
+
+static void axp20x_gpio_set(struct gpio_chip *chip, unsigned int offset,
+			    int value)
+{
+	axp20x_gpio_output(chip, offset, value);
+}
+
+static int axp20x_gpio_probe(struct platform_device *pdev)
+{
+	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
+	struct axp20x_gpio *gpio;
+	int ret;
+
+	if (!of_device_is_available(pdev->dev.of_node))
+		return -ENODEV;
+
+	if (!axp20x) {
+		dev_err(&pdev->dev, "Parent drvdata not set\n");
+		return -EINVAL;
+	}
+
+	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
+	if (!gpio)
+		return -ENOMEM;
+
+	gpio->chip.base			= -1;
+	gpio->chip.can_sleep		= true;
+	gpio->chip.parent		= &pdev->dev;
+	gpio->chip.label		= dev_name(&pdev->dev);
+	gpio->chip.owner		= THIS_MODULE;
+	gpio->chip.get			= axp20x_gpio_get;
+	gpio->chip.get_direction	= axp20x_gpio_get_direction;
+	gpio->chip.set			= axp20x_gpio_set;
+	gpio->chip.direction_input	= axp20x_gpio_input;
+	gpio->chip.direction_output	= axp20x_gpio_output;
+	gpio->chip.ngpio		= 3;
+
+	gpio->regmap = axp20x->regmap;
+
+	ret = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to register GPIO chip\n");
+		return ret;
+	}
+
+	dev_info(&pdev->dev, "AXP209 GPIO driver loaded\n");
+
+	return 0;
+}
+
+static const struct of_device_id axp20x_gpio_match[] = {
+	{ .compatible = "x-powers,axp209-gpio" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, axp20x_gpio_match);
+
+static struct platform_driver axp20x_gpio_driver = {
+	.probe		= axp20x_gpio_probe,
+	.driver = {
+		.name		= "axp20x-gpio",
+		.of_match_table	= axp20x_gpio_match,
+	},
+};
+
+module_platform_driver(axp20x_gpio_driver);
+
+MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
+MODULE_DESCRIPTION("AXP20x PMIC GPIO driver");
+MODULE_LICENSE("GPL");