pinctrl: add abx500 pinctrl driver core

This adds the AB8500 core driver, which will be utilized by
the follow-on drivers for different ABx500 variants.
Sselect the driver from the DBX500_SOC, as this chip is
powering and clocking that SoC.

Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 1233 insertions, 0 deletions

diff --git a/drivers/pinctrl/pinctrl-abx500.c b/drivers/pinctrl/pinctrl-abx500.c
new file mode 100644
index 00000000000..9eed9887da2
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-abx500.c
@@ -0,0 +1,1233 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2013
+ *
+ * Author: Patrice Chotard <patrice.chotard@st.com>
+ * License terms: GNU General Public License (GPL) version 2
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/bitops.h>
+#include <linux/mfd/abx500.h>
+#include <linux/mfd/abx500/ab8500.h>
+#include <linux/mfd/abx500/ab8500-gpio.h>
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/pinctrl/pinmux.h>
+#include <linux/pinctrl/pinconf.h>
+#include <linux/pinctrl/pinconf-generic.h>
+
+#include "pinctrl-abx500.h"
+
+/*
+ * The AB9540 and AB8540 GPIO support are extended versions
+ * of the AB8500 GPIO support.
+ * The AB9540 supports an additional (7th) register so that
+ * more GPIO may be configured and used.
+ * The AB8540 supports 4 new gpios (GPIOx_VBAT) that have
+ * internal pull-up and pull-down capabilities.
+ */
+
+/*
+ * GPIO registers offset
+ * Bank: 0x10
+ */
+#define AB8500_GPIO_SEL1_REG	0x00
+#define AB8500_GPIO_SEL2_REG	0x01
+#define AB8500_GPIO_SEL3_REG	0x02
+#define AB8500_GPIO_SEL4_REG	0x03
+#define AB8500_GPIO_SEL5_REG	0x04
+#define AB8500_GPIO_SEL6_REG	0x05
+#define AB9540_GPIO_SEL7_REG	0x06
+
+#define AB8500_GPIO_DIR1_REG	0x10
+#define AB8500_GPIO_DIR2_REG	0x11
+#define AB8500_GPIO_DIR3_REG	0x12
+#define AB8500_GPIO_DIR4_REG	0x13
+#define AB8500_GPIO_DIR5_REG	0x14
+#define AB8500_GPIO_DIR6_REG	0x15
+#define AB9540_GPIO_DIR7_REG	0x16
+
+#define AB8500_GPIO_OUT1_REG	0x20
+#define AB8500_GPIO_OUT2_REG	0x21
+#define AB8500_GPIO_OUT3_REG	0x22
+#define AB8500_GPIO_OUT4_REG	0x23
+#define AB8500_GPIO_OUT5_REG	0x24
+#define AB8500_GPIO_OUT6_REG	0x25
+#define AB9540_GPIO_OUT7_REG	0x26
+
+#define AB8500_GPIO_PUD1_REG	0x30
+#define AB8500_GPIO_PUD2_REG	0x31
+#define AB8500_GPIO_PUD3_REG	0x32
+#define AB8500_GPIO_PUD4_REG	0x33
+#define AB8500_GPIO_PUD5_REG	0x34
+#define AB8500_GPIO_PUD6_REG	0x35
+#define AB9540_GPIO_PUD7_REG	0x36
+
+#define AB8500_GPIO_IN1_REG	0x40
+#define AB8500_GPIO_IN2_REG	0x41
+#define AB8500_GPIO_IN3_REG	0x42
+#define AB8500_GPIO_IN4_REG	0x43
+#define AB8500_GPIO_IN5_REG	0x44
+#define AB8500_GPIO_IN6_REG	0x45
+#define AB9540_GPIO_IN7_REG	0x46
+#define AB8540_GPIO_VINSEL_REG	0x47
+#define AB8540_GPIO_PULL_UPDOWN_REG	0x48
+#define AB8500_GPIO_ALTFUN_REG	0x50
+#define AB8500_NUM_VIR_GPIO_IRQ	16
+#define AB8540_GPIO_PULL_UPDOWN_MASK	0x03
+#define AB8540_GPIO_VINSEL_MASK	0x03
+#define AB8540_GPIOX_VBAT_START	51
+#define AB8540_GPIOX_VBAT_END	54
+
+enum abx500_gpio_action {
+	NONE,
+	STARTUP,
+	SHUTDOWN,
+	MASK,
+	UNMASK
+};
+
+struct abx500_pinctrl {
+	struct device *dev;
+	struct pinctrl_dev *pctldev;
+	struct abx500_pinctrl_soc_data *soc;
+	struct gpio_chip chip;
+	struct ab8500 *parent;
+	struct mutex lock;
+	u32 irq_base;
+	enum abx500_gpio_action irq_action;
+	u16 rising;
+	u16 falling;
+	struct abx500_gpio_irq_cluster *irq_cluster;
+	int irq_cluster_size;
+	int irq_gpio_rising_offset;
+	int irq_gpio_falling_offset;
+	int irq_gpio_factor;
+};
+
+/**
+ * to_abx500_pinctrl() - get the pointer to abx500_pinctrl
+ * @chip:	Member of the structure abx500_pinctrl
+ */
+static inline struct abx500_pinctrl *to_abx500_pinctrl(struct gpio_chip *chip)
+{
+	return container_of(chip, struct abx500_pinctrl, chip);
+}
+
+static int abx500_gpio_get_bit(struct gpio_chip *chip, u8 reg,
+					unsigned offset, bool *bit)
+{
+	struct abx500_pinctrl *pct = to_abx500_pinctrl(chip);
+	u8 pos = offset % 8;
+	u8 val;
+	int ret;
+
+	reg += offset / 8;
+	ret = abx500_get_register_interruptible(pct->dev,
+						AB8500_MISC, reg, &val);
+
+	*bit = !!(val & BIT(pos));
+
+	if (ret < 0)
+		dev_err(pct->dev,
+			"%s read reg =%x, offset=%x failed\n",
+			__func__, reg, offset);
+
+	return ret;
+}
+
+static int abx500_gpio_set_bits(struct gpio_chip *chip, u8 reg,
+					unsigned offset, int val)
+{
+	struct abx500_pinctrl *pct = to_abx500_pinctrl(chip);
+	u8 pos = offset % 8;
+	int ret;
+
+	reg += offset / 8;
+	ret = abx500_mask_and_set_register_interruptible(pct->dev,
+				AB8500_MISC, reg, 1 << pos, val << pos);
+	if (ret < 0)
+		dev_err(pct->dev, "%s write failed\n", __func__);
+	return ret;
+}
+/**
+ * abx500_gpio_get() - Get the particular GPIO value
+ * @chip: Gpio device
+ * @offset: GPIO number to read
+ */
+static int abx500_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+	struct abx500_pinctrl *pct = to_abx500_pinctrl(chip);
+	bool bit;
+	int ret;
+
+	ret = abx500_gpio_get_bit(chip, AB8500_GPIO_IN1_REG,
+				  offset, &bit);
+	if (ret < 0) {
+		dev_err(pct->dev, "%s failed\n", __func__);
+		return ret;
+	}
+	return bit;
+}
+
+static void abx500_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
+{
+	struct abx500_pinctrl *pct = to_abx500_pinctrl(chip);
+	int ret;
+
+	ret = abx500_gpio_set_bits(chip, AB8500_GPIO_OUT1_REG, offset, val);
+	if (ret < 0)
+		dev_err(pct->dev, "%s write failed\n", __func__);
+}
+
+static int abx500_config_pull_updown(struct abx500_pinctrl *pct,
+				int offset, enum abx500_gpio_pull_updown val)
+{
+	u8 pos;
+	int ret;
+	struct pullud *pullud;
+
+	if (!pct->soc->pullud) {
+		dev_err(pct->dev, "%s AB chip doesn't support pull up/down feature",
+				__func__);
+		ret = -EPERM;
+		goto out;
+	}
+
+	pullud = pct->soc->pullud;
+
+	if ((offset < pullud->first_pin)
+		|| (offset > pullud->last_pin)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	pos = offset << 1;
+
+	ret = abx500_mask_and_set_register_interruptible(pct->dev,
+			AB8500_MISC, AB8540_GPIO_PULL_UPDOWN_REG,
+			AB8540_GPIO_PULL_UPDOWN_MASK << pos, val << pos);
+
+out:
+	if (ret < 0)
+		dev_err(pct->dev, "%s failed (%d)\n", __func__, ret);
+	return ret;
+}
+
+static int abx500_gpio_direction_output(struct gpio_chip *chip,
+					unsigned offset,
+					int val)
+{
+	struct abx500_pinctrl *pct = to_abx500_pinctrl(chip);
+	struct pullud *pullud = pct->soc->pullud;
+	unsigned gpio;
+	int ret;
+	/* set direction as output */
+	ret = abx500_gpio_set_bits(chip, AB8500_GPIO_DIR1_REG, offset, 1);
+	if (ret < 0)
+		return ret;
+
+	/* disable pull down */
+	ret = abx500_gpio_set_bits(chip, AB8500_GPIO_PUD1_REG, offset, 1);
+	if (ret < 0)
+		return ret;
+
+	/* if supported, disable both pull down and pull up */
+	gpio = offset + 1;
+	if (pullud && gpio >= pullud->first_pin && gpio <= pullud->last_pin) {
+		ret = abx500_config_pull_updown(pct,
+				gpio,
+				ABX500_GPIO_PULL_NONE);
+		if (ret < 0)
+			return ret;
+	}
+	/* set the output as 1 or 0 */
+	return abx500_gpio_set_bits(chip, AB8500_GPIO_OUT1_REG, offset, val);
+}
+
+static int abx500_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+	/* set the register as input */
+	return abx500_gpio_set_bits(chip, AB8500_GPIO_DIR1_REG, offset, 0);
+}
+
+static int abx500_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+	struct abx500_pinctrl *pct = to_abx500_pinctrl(chip);
+	int base = pct->irq_base;
+	int i;
+
+	for (i = 0; i < pct->irq_cluster_size; i++) {
+		struct abx500_gpio_irq_cluster *cluster =
+			&pct->irq_cluster[i];
+
+		if (offset >= cluster->start && offset <= cluster->end)
+			return base + offset - cluster->start;
+
+		/* Advance by the number of gpios in this cluster */
+		base += cluster->end + cluster->offset - cluster->start + 1;
+	}
+
+	return -EINVAL;
+}
+
+static int abx500_set_mode(struct pinctrl_dev *pctldev, struct gpio_chip *chip,
+		unsigned gpio, int alt_setting)
+{
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+	struct alternate_functions af = pct->soc->alternate_functions[gpio];
+	int ret;
+	int val;
+	unsigned offset;
+	const char *modes[] = {
+		[ABX500_DEFAULT]	= "default",
+		[ABX500_ALT_A]		= "altA",
+		[ABX500_ALT_B]		= "altB",
+		[ABX500_ALT_C]		= "altC",
+	};
+
+	/* sanity check */
+	if (((alt_setting == ABX500_ALT_A) && (af.gpiosel_bit == UNUSED)) ||
+	    ((alt_setting == ABX500_ALT_B) && (af.alt_bit1 == UNUSED)) ||
+	    ((alt_setting == ABX500_ALT_C) && (af.alt_bit2 == UNUSED))) {
+		dev_dbg(pct->dev, "pin %d doesn't support %s mode\n", gpio,
+				modes[alt_setting]);
+		return -EINVAL;
+	}
+
+	/* on ABx5xx, there is no GPIO0, so adjust the offset */
+	offset = gpio - 1;
+	switch (alt_setting) {
+	case ABX500_DEFAULT:
+		/*
+		 * for ABx5xx family, default mode is always selected by
+		 * writing 0 to GPIOSELx register, except for pins which
+		 * support at least ALT_B mode, default mode is selected
+		 * by writing 1 to GPIOSELx register
+		 */
+		val = 0;
+		if (af.alt_bit1 != UNUSED)
+			val++;
+
+		ret = abx500_gpio_set_bits(chip, AB8500_GPIO_SEL1_REG,
+					   offset, val);
+		break;
+	case ABX500_ALT_A:
+		/*
+		 * for ABx5xx family, alt_a mode is always selected by
+		 * writing 1 to GPIOSELx register, except for pins which
+		 * support at least ALT_B mode, alt_a mode is selected
+		 * by writing 0 to GPIOSELx register and 0 in ALTFUNC
+		 * register
+		 */
+		if (af.alt_bit1 != UNUSED) {
+			ret = abx500_gpio_set_bits(chip, AB8500_GPIO_SEL1_REG,
+					offset, 0);
+			ret = abx500_gpio_set_bits(chip,
+					AB8500_GPIO_ALTFUN_REG,
+					af.alt_bit1,
+					!!(af.alta_val && BIT(0)));
+			if (af.alt_bit2 != UNUSED)
+				ret = abx500_gpio_set_bits(chip,
+					AB8500_GPIO_ALTFUN_REG,
+					af.alt_bit2,
+					!!(af.alta_val && BIT(1)));
+		} else
+			ret = abx500_gpio_set_bits(chip, AB8500_GPIO_SEL1_REG,
+					offset, 1);
+		break;
+	case ABX500_ALT_B:
+		ret = abx500_gpio_set_bits(chip, AB8500_GPIO_SEL1_REG,
+				offset, 0);
+		ret = abx500_gpio_set_bits(chip, AB8500_GPIO_ALTFUN_REG,
+				af.alt_bit1, !!(af.altb_val && BIT(0)));
+		if (af.alt_bit2 != UNUSED)
+			ret = abx500_gpio_set_bits(chip,
+					AB8500_GPIO_ALTFUN_REG,
+					af.alt_bit2,
+					!!(af.altb_val && BIT(1)));
+		break;
+	case ABX500_ALT_C:
+		ret = abx500_gpio_set_bits(chip, AB8500_GPIO_SEL1_REG,
+				offset, 0);
+		ret = abx500_gpio_set_bits(chip, AB8500_GPIO_ALTFUN_REG,
+				af.alt_bit2, !!(af.altc_val && BIT(0)));
+		ret = abx500_gpio_set_bits(chip, AB8500_GPIO_ALTFUN_REG,
+				af.alt_bit2, !!(af.altc_val && BIT(1)));
+		break;
+
+	default:
+		dev_dbg(pct->dev, "unknow alt_setting %d\n", alt_setting);
+		return -EINVAL;
+	}
+	return ret;
+}
+
+static u8 abx500_get_mode(struct pinctrl_dev *pctldev, struct gpio_chip *chip,
+		unsigned gpio)
+{
+	u8 mode;
+	bool bit_mode;
+	bool alt_bit1;
+	bool alt_bit2;
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+	struct alternate_functions af = pct->soc->alternate_functions[gpio];
+
+	/*
+	 * if gpiosel_bit is set to unused,
+	 * it means no GPIO or special case
+	 */
+	if (af.gpiosel_bit == UNUSED)
+		return ABX500_DEFAULT;
+
+	/* read GpioSelx register */
+	abx500_gpio_get_bit(chip, AB8500_GPIO_SEL1_REG + (gpio / 8),
+			af.gpiosel_bit, &bit_mode);
+	mode = bit_mode;
+
+	/* sanity check */
+	if ((af.alt_bit1 < UNUSED) || (af.alt_bit1 > 7) ||
+	    (af.alt_bit2 < UNUSED) || (af.alt_bit2 > 7)) {
+		dev_err(pct->dev,
+			"alt_bitX value not in correct range (-1 to 7)\n");
+		return -EINVAL;
+	}
+	/* if alt_bit2 is used, alt_bit1 must be used too */
+	if ((af.alt_bit2 != UNUSED) && (af.alt_bit1 == UNUSED)) {
+		dev_err(pct->dev,
+			"if alt_bit2 is used, alt_bit1 can't be unused\n");
+		return -EINVAL;
+	}
+
+	/* check if pin use AlternateFunction register */
+	if ((af.alt_bit1 == UNUSED) && (af.alt_bit1 == UNUSED))
+		return mode;
+	/*
+	 * if pin GPIOSEL bit is set and pin supports alternate function,
+	 * it means DEFAULT mode
+	 */
+	if (mode)
+		return ABX500_DEFAULT;
+	/*
+	 * pin use the AlternatFunction register
+	 * read alt_bit1 value
+	 */
+	abx500_gpio_get_bit(chip, AB8500_GPIO_ALTFUN_REG,
+			    af.alt_bit1, &alt_bit1);
+
+	if (af.alt_bit2 != UNUSED)
+		/* read alt_bit2 value */
+		abx500_gpio_get_bit(chip, AB8500_GPIO_ALTFUN_REG, af.alt_bit2,
+				&alt_bit2);
+	else
+		alt_bit2 = 0;
+
+	mode = (alt_bit2 << 1) + alt_bit1;
+	if (mode == af.alta_val)
+		return ABX500_ALT_A;
+	else if (mode == af.altb_val)
+		return ABX500_ALT_B;
+	else
+		return ABX500_ALT_C;
+}
+
+#ifdef CONFIG_DEBUG_FS
+
+#include <linux/seq_file.h>
+
+static void abx500_gpio_dbg_show_one(struct seq_file *s,
+	struct pinctrl_dev *pctldev, struct gpio_chip *chip,
+	unsigned offset, unsigned gpio)
+{
+	struct abx500_pinctrl *pct = to_abx500_pinctrl(chip);
+	const char *label = gpiochip_is_requested(chip, offset - 1);
+	u8 gpio_offset = offset - 1;
+	int mode = -1;
+	bool is_out;
+	bool pull;
+	const char *modes[] = {
+		[ABX500_DEFAULT]	= "default",
+		[ABX500_ALT_A]		= "altA",
+		[ABX500_ALT_B]		= "altB",
+		[ABX500_ALT_C]		= "altC",
+	};
+
+	abx500_gpio_get_bit(chip, AB8500_GPIO_DIR1_REG, gpio_offset, &is_out);
+	abx500_gpio_get_bit(chip, AB8500_GPIO_PUD1_REG, gpio_offset, &pull);
+
+	if (pctldev)
+		mode = abx500_get_mode(pctldev, chip, offset);
+
+	seq_printf(s, " gpio-%-3d (%-20.20s) %-3s %-9s %s",
+		   gpio, label ?: "(none)",
+		   is_out ? "out" : "in ",
+		   is_out ?
+		   (chip->get
+		   ? (chip->get(chip, offset) ? "hi" : "lo")
+		   : "?  ")
+		   : (pull ? "pull up" : "pull down"),
+		   (mode < 0) ? "unknown" : modes[mode]);
+
+	if (label && !is_out) {
+		int irq = gpio_to_irq(gpio);
+		struct irq_desc	*desc = irq_to_desc(irq);
+
+		if (irq >= 0 && desc->action) {
+			char *trigger;
+			int irq_offset = irq - pct->irq_base;
+
+			if (pct->rising & BIT(irq_offset))
+				trigger = "edge-rising";
+			else if (pct->falling & BIT(irq_offset))
+				trigger = "edge-falling";
+			else
+				trigger = "edge-undefined";
+
+			seq_printf(s, " irq-%d %s", irq, trigger);
+		}
+	}
+}
+
+static void abx500_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
+{
+	unsigned i;
+	unsigned gpio = chip->base;
+	struct abx500_pinctrl *pct = to_abx500_pinctrl(chip);
+	struct pinctrl_dev *pctldev = pct->pctldev;
+
+	for (i = 0; i < chip->ngpio; i++, gpio++) {
+		/* On AB8500, there is no GPIO0, the first is the GPIO 1 */
+		abx500_gpio_dbg_show_one(s, pctldev, chip, i + 1, gpio);
+		seq_printf(s, "\n");
+	}
+}
+
+#else
+static inline void abx500_gpio_dbg_show_one(struct seq_file *s,
+					 struct pinctrl_dev *pctldev,
+					 struct gpio_chip *chip,
+					 unsigned offset, unsigned gpio)
+{
+}
+#define abx500_gpio_dbg_show	NULL
+#endif
+
+int abx500_gpio_request(struct gpio_chip *chip, unsigned offset)
+{
+	int gpio = chip->base + offset;
+
+	return pinctrl_request_gpio(gpio);
+}
+
+void abx500_gpio_free(struct gpio_chip *chip, unsigned offset)
+{
+	int gpio = chip->base + offset;
+
+	pinctrl_free_gpio(gpio);
+}
+
+static struct gpio_chip abx500gpio_chip = {
+	.label			= "abx500-gpio",
+	.owner			= THIS_MODULE,
+	.request		= abx500_gpio_request,
+	.free			= abx500_gpio_free,
+	.direction_input	= abx500_gpio_direction_input,
+	.get			= abx500_gpio_get,
+	.direction_output	= abx500_gpio_direction_output,
+	.set			= abx500_gpio_set,
+	.to_irq			= abx500_gpio_to_irq,
+	.dbg_show		= abx500_gpio_dbg_show,
+};
+
+static unsigned int irq_to_rising(unsigned int irq)
+{
+	struct abx500_pinctrl *pct = irq_get_chip_data(irq);
+	int offset = irq - pct->irq_base;
+	int new_irq;
+
+	new_irq = offset * pct->irq_gpio_factor
+		+ pct->irq_gpio_rising_offset
+		+ pct->parent->irq_base;
+
+	return new_irq;
+}
+
+static unsigned int irq_to_falling(unsigned int irq)
+{
+	struct abx500_pinctrl *pct = irq_get_chip_data(irq);
+	int offset = irq - pct->irq_base;
+	int new_irq;
+
+	new_irq = offset * pct->irq_gpio_factor
+		+ pct->irq_gpio_falling_offset
+		+ pct->parent->irq_base;
+	return new_irq;
+
+}
+
+static unsigned int rising_to_irq(unsigned int irq, void *dev)
+{
+	struct abx500_pinctrl *pct = dev;
+	int offset, new_irq;
+
+	offset = irq - pct->irq_gpio_rising_offset
+		- pct->parent->irq_base;
+	new_irq = (offset / pct->irq_gpio_factor)
+		+ pct->irq_base;
+
+	return new_irq;
+}
+
+static unsigned int falling_to_irq(unsigned int irq, void *dev)
+{
+	struct abx500_pinctrl *pct = dev;
+	int offset, new_irq;
+
+	offset = irq - pct->irq_gpio_falling_offset
+		- pct->parent->irq_base;
+	new_irq = (offset / pct->irq_gpio_factor)
+		+ pct->irq_base;
+
+	return new_irq;
+}
+
+/*
+ * IRQ handler
+ */
+
+static irqreturn_t handle_rising(int irq, void *dev)
+{
+
+	handle_nested_irq(rising_to_irq(irq , dev));
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t handle_falling(int irq, void *dev)
+{
+
+	handle_nested_irq(falling_to_irq(irq, dev));
+	return IRQ_HANDLED;
+}
+
+static void abx500_gpio_irq_lock(struct irq_data *data)
+{
+	struct abx500_pinctrl *pct = irq_data_get_irq_chip_data(data);
+	mutex_lock(&pct->lock);
+}
+
+static void abx500_gpio_irq_sync_unlock(struct irq_data *data)
+{
+	struct abx500_pinctrl *pct = irq_data_get_irq_chip_data(data);
+	unsigned int irq = data->irq;
+	int offset = irq - pct->irq_base;
+	bool rising = pct->rising & BIT(offset);
+	bool falling = pct->falling & BIT(offset);
+	int ret;
+
+	switch (pct->irq_action)	{
+	case STARTUP:
+		if (rising)
+			ret = request_threaded_irq(irq_to_rising(irq),
+					NULL, handle_rising,
+					IRQF_TRIGGER_RISING | IRQF_NO_SUSPEND,
+					"abx500-gpio-r", pct);
+		if (falling)
+			ret = request_threaded_irq(irq_to_falling(irq),
+				       NULL, handle_falling,
+				       IRQF_TRIGGER_FALLING | IRQF_NO_SUSPEND,
+				       "abx500-gpio-f", pct);
+		break;
+	case SHUTDOWN:
+		if (rising)
+			free_irq(irq_to_rising(irq), pct);
+		if (falling)
+			free_irq(irq_to_falling(irq), pct);
+		break;
+	case MASK:
+		if (rising)
+			disable_irq(irq_to_rising(irq));
+		if (falling)
+			disable_irq(irq_to_falling(irq));
+		break;
+	case UNMASK:
+		if (rising)
+			enable_irq(irq_to_rising(irq));
+		if (falling)
+			enable_irq(irq_to_falling(irq));
+		break;
+	case NONE:
+		break;
+	}
+	pct->irq_action = NONE;
+	pct->rising &= ~(BIT(offset));
+	pct->falling &= ~(BIT(offset));
+	mutex_unlock(&pct->lock);
+}
+
+
+static void abx500_gpio_irq_mask(struct irq_data *data)
+{
+	struct abx500_pinctrl *pct = irq_data_get_irq_chip_data(data);
+	pct->irq_action = MASK;
+}
+
+static void abx500_gpio_irq_unmask(struct irq_data *data)
+{
+	struct abx500_pinctrl *pct =  irq_data_get_irq_chip_data(data);
+	pct->irq_action = UNMASK;
+}
+
+static int abx500_gpio_irq_set_type(struct irq_data *data, unsigned int type)
+{
+	struct abx500_pinctrl *pct = irq_data_get_irq_chip_data(data);
+	unsigned int irq = data->irq;
+	int offset = irq - pct->irq_base;
+
+	if (type == IRQ_TYPE_EDGE_BOTH) {
+		pct->rising =  BIT(offset);
+		pct->falling = BIT(offset);
+	} else if (type == IRQ_TYPE_EDGE_RISING) {
+		pct->rising =  BIT(offset);
+	} else  {
+		pct->falling = BIT(offset);
+	}
+	return 0;
+}
+
+static unsigned int abx500_gpio_irq_startup(struct irq_data *data)
+{
+	struct abx500_pinctrl *pct = irq_data_get_irq_chip_data(data);
+	pct->irq_action = STARTUP;
+	return 0;
+}
+
+static void abx500_gpio_irq_shutdown(struct irq_data *data)
+{
+	struct abx500_pinctrl *pct = irq_data_get_irq_chip_data(data);
+	pct->irq_action = SHUTDOWN;
+}
+
+static struct irq_chip abx500_gpio_irq_chip = {
+	.name			= "abx500-gpio",
+	.irq_startup		= abx500_gpio_irq_startup,
+	.irq_shutdown		= abx500_gpio_irq_shutdown,
+	.irq_bus_lock		= abx500_gpio_irq_lock,
+	.irq_bus_sync_unlock	= abx500_gpio_irq_sync_unlock,
+	.irq_mask		= abx500_gpio_irq_mask,
+	.irq_unmask		= abx500_gpio_irq_unmask,
+	.irq_set_type		= abx500_gpio_irq_set_type,
+};
+
+static int abx500_gpio_irq_init(struct abx500_pinctrl *pct)
+{
+	u32 base = pct->irq_base;
+	int irq;
+
+	for (irq = base; irq < base + AB8500_NUM_VIR_GPIO_IRQ ; irq++) {
+		irq_set_chip_data(irq, pct);
+		irq_set_chip_and_handler(irq, &abx500_gpio_irq_chip,
+				handle_simple_irq);
+		irq_set_nested_thread(irq, 1);
+#ifdef CONFIG_ARM
+		set_irq_flags(irq, IRQF_VALID);
+#else
+		irq_set_noprobe(irq);
+#endif
+	}
+
+	return 0;
+}
+
+static void abx500_gpio_irq_remove(struct abx500_pinctrl *pct)
+{
+	int base = pct->irq_base;
+	int irq;
+
+	for (irq = base; irq < base + AB8500_NUM_VIR_GPIO_IRQ; irq++) {
+#ifdef CONFIG_ARM
+		set_irq_flags(irq, 0);
+#endif
+		irq_set_chip_and_handler(irq, NULL, NULL);
+		irq_set_chip_data(irq, NULL);
+	}
+}
+
+static int abx500_pmx_get_funcs_cnt(struct pinctrl_dev *pctldev)
+{
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+
+	return pct->soc->nfunctions;
+}
+
+static const char *abx500_pmx_get_func_name(struct pinctrl_dev *pctldev,
+					 unsigned function)
+{
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+
+	return pct->soc->functions[function].name;
+}
+
+static int abx500_pmx_get_func_groups(struct pinctrl_dev *pctldev,
+				   unsigned function,
+				   const char * const **groups,
+				   unsigned * const num_groups)
+{
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+
+	*groups = pct->soc->functions[function].groups;
+	*num_groups = pct->soc->functions[function].ngroups;
+
+	return 0;
+}
+
+static void abx500_disable_lazy_irq(struct gpio_chip *chip, unsigned gpio)
+{
+	struct abx500_pinctrl *pct = to_abx500_pinctrl(chip);
+	int irq;
+	int offset;
+	bool rising;
+	bool falling;
+
+	/*
+	 * check if gpio has interrupt capability and convert
+	 * gpio number to irq
+	 * On ABx5xx, there is no GPIO0, GPIO1 is the
+	 * first one, so adjust gpio number
+	 */
+	gpio--;
+	irq =  gpio_to_irq(gpio + chip->base);
+	if (irq < 0)
+		return;
+
+	offset = irq - pct->irq_base;
+	rising = pct->rising & BIT(offset);
+	falling = pct->falling & BIT(offset);
+
+	/* nothing to do ?*/
+	if (!rising && !falling)
+		return;
+
+	if (rising) {
+		disable_irq(irq_to_rising(irq));
+		free_irq(irq_to_rising(irq), pct);
+	}
+	if (falling) {
+		disable_irq(irq_to_falling(irq));
+		free_irq(irq_to_falling(irq), pct);
+	}
+}
+
+static int abx500_pmx_enable(struct pinctrl_dev *pctldev, unsigned function,
+			  unsigned group)
+{
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+	struct gpio_chip *chip = &pct->chip;
+	const struct abx500_pingroup *g;
+	int i;
+	int ret = 0;
+
+	g = &pct->soc->groups[group];
+	if (g->altsetting < 0)
+		return -EINVAL;
+
+	dev_dbg(pct->dev, "enable group %s, %u pins\n", g->name, g->npins);
+
+	for (i = 0; i < g->npins; i++) {
+		dev_dbg(pct->dev, "setting pin %d to altsetting %d\n",
+			g->pins[i], g->altsetting);
+
+		abx500_disable_lazy_irq(chip, g->pins[i]);
+		ret = abx500_set_mode(pctldev, chip, g->pins[i], g->altsetting);
+	}
+	return ret;
+}
+
+static void abx500_pmx_disable(struct pinctrl_dev *pctldev,
+			    unsigned function, unsigned group)
+{
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+	const struct abx500_pingroup *g;
+
+	g = &pct->soc->groups[group];
+	if (g->altsetting < 0)
+		return;
+
+	/* FIXME: poke out the mux, set the pin to some default state? */
+	dev_dbg(pct->dev, "disable group %s, %u pins\n", g->name, g->npins);
+}
+
+int abx500_gpio_request_enable(struct pinctrl_dev *pctldev,
+			    struct pinctrl_gpio_range *range,
+			    unsigned offset)
+{
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+	const struct abx500_pinrange *p;
+	int ret;
+	int i;
+
+	/*
+	 * Different ranges have different ways to enable GPIO function on a
+	 * pin, so refer back to our local range type, where we handily define
+	 * what altfunc enables GPIO for a certain pin.
+	 */
+	for (i = 0; i < pct->soc->gpio_num_ranges; i++) {
+		p = &pct->soc->gpio_ranges[i];
+		if ((offset >= p->offset) &&
+		    (offset < (p->offset + p->npins)))
+		  break;
+	}
+
+	if (i == pct->soc->gpio_num_ranges) {
+		dev_err(pct->dev, "%s failed to locate range\n", __func__);
+		return -ENODEV;
+	}
+
+	dev_dbg(pct->dev, "enable GPIO by altfunc %d at gpio %d\n",
+		p->altfunc, offset);
+
+	ret = abx500_set_mode(pct->pctldev, &pct->chip,
+			      offset, p->altfunc);
+	if (ret < 0) {
+		dev_err(pct->dev, "%s setting altfunc failed\n", __func__);
+		return ret;
+	}
+
+	return ret;
+}
+
+static void abx500_gpio_disable_free(struct pinctrl_dev *pctldev,
+			   struct pinctrl_gpio_range *range,
+			   unsigned offset)
+{
+}
+
+static struct pinmux_ops abx500_pinmux_ops = {
+	.get_functions_count = abx500_pmx_get_funcs_cnt,
+	.get_function_name = abx500_pmx_get_func_name,
+	.get_function_groups = abx500_pmx_get_func_groups,
+	.enable = abx500_pmx_enable,
+	.disable = abx500_pmx_disable,
+	.gpio_request_enable = abx500_gpio_request_enable,
+	.gpio_disable_free = abx500_gpio_disable_free,
+};
+
+static int abx500_get_groups_cnt(struct pinctrl_dev *pctldev)
+{
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+
+	return pct->soc->ngroups;
+}
+
+static const char *abx500_get_group_name(struct pinctrl_dev *pctldev,
+				       unsigned selector)
+{
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+
+	return pct->soc->groups[selector].name;
+}
+
+static int abx500_get_group_pins(struct pinctrl_dev *pctldev,
+		unsigned selector,
+		const unsigned **pins,
+		unsigned *num_pins)
+{
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+
+	*pins = pct->soc->groups[selector].pins;
+	*num_pins = pct->soc->groups[selector].npins;
+	return 0;
+}
+
+static void abx500_pin_dbg_show(struct pinctrl_dev *pctldev,
+		struct seq_file *s, unsigned offset)
+{
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+	struct gpio_chip *chip = &pct->chip;
+
+	abx500_gpio_dbg_show_one(s, pctldev, chip, offset,
+				 chip->base + offset - 1);
+}
+
+static struct pinctrl_ops abx500_pinctrl_ops = {
+	.get_groups_count = abx500_get_groups_cnt,
+	.get_group_name = abx500_get_group_name,
+	.get_group_pins = abx500_get_group_pins,
+	.pin_dbg_show = abx500_pin_dbg_show,
+};
+
+int abx500_pin_config_get(struct pinctrl_dev *pctldev,
+		       unsigned pin,
+		       unsigned long *config)
+{
+	/* Not implemented */
+	return -EINVAL;
+}
+
+int abx500_pin_config_set(struct pinctrl_dev *pctldev,
+		       unsigned pin,
+		       unsigned long config)
+{
+	struct abx500_pinctrl *pct = pinctrl_dev_get_drvdata(pctldev);
+	struct pullud *pullud = pct->soc->pullud;
+	struct gpio_chip *chip = &pct->chip;
+	unsigned offset;
+	int ret;
+	enum pin_config_param param = pinconf_to_config_param(config);
+	enum pin_config_param argument = pinconf_to_config_argument(config);
+
+	dev_dbg(chip->dev, "pin %d [%#lx]: %s %s\n",
+		pin, config, (param == PIN_CONFIG_OUTPUT) ? "output " : "input",
+		(param == PIN_CONFIG_OUTPUT) ? (argument ? "high" : "low") :
+		(argument ? "pull up" : "pull down"));
+	/* on ABx500, there is no GPIO0, so adjust the offset */
+	offset = pin - 1;
+
+	switch (param) {
+	case PIN_CONFIG_BIAS_PULL_DOWN:
+		/*
+		 * if argument = 1 set the pull down
+		 * else clear the pull down
+		 */
+		ret = abx500_gpio_direction_input(chip, offset);
+		/*
+		 * Some chips only support pull down, while some actually
+		 * support both pull up and pull down. Such chips have
+		 * a "pullud" range specified for the pins that support
+		 * both features. If the pin is not within that range, we
+		 * fall back to the old bit set that only support pull down.
+		 */
+		if (pullud &&
+		    pin >= pullud->first_pin &&
+		    pin <= pullud->last_pin)
+			ret = abx500_config_pull_updown(pct,
+				pin,
+				argument ? ABX500_GPIO_PULL_DOWN : ABX500_GPIO_PULL_NONE);
+		else
+			/* Chip only supports pull down */
+			ret = abx500_gpio_set_bits(chip, AB8500_GPIO_PUD1_REG,
+				offset, argument ? 0 : 1);
+		break;
+	case PIN_CONFIG_OUTPUT:
+		ret = abx500_gpio_direction_output(chip, offset, argument);
+		break;
+	default:
+		dev_err(chip->dev, "illegal configuration requested\n");
+		return -EINVAL;
+	}
+	return ret;
+}
+
+static struct pinconf_ops abx500_pinconf_ops = {
+	.pin_config_get = abx500_pin_config_get,
+	.pin_config_set = abx500_pin_config_set,
+};
+
+static struct pinctrl_desc abx500_pinctrl_desc = {
+	.name = "pinctrl-abx500",
+	.pctlops = &abx500_pinctrl_ops,
+	.pmxops = &abx500_pinmux_ops,
+	.confops = &abx500_pinconf_ops,
+	.owner = THIS_MODULE,
+};
+
+static int abx500_get_gpio_num(struct abx500_pinctrl_soc_data *soc)
+{
+	unsigned int lowest = 0;
+	unsigned int highest = 0;
+	unsigned int npins = 0;
+	int i;
+
+	/*
+	 * Compute number of GPIOs from the last SoC gpio range descriptors
+	 * These ranges may include "holes" but the GPIO number space shall
+	 * still be homogeneous, so we need to detect and account for any
+	 * such holes so that these are included in the number of GPIO pins.
+	 */
+	for (i = 0; i < soc->gpio_num_ranges; i++) {
+		unsigned gstart;
+		unsigned gend;
+		const struct abx500_pinrange *p;
+
+		p = &soc->gpio_ranges[i];
+		gstart = p->offset;
+		gend = p->offset + p->npins - 1;
+
+		if (i == 0) {
+			/* First iteration, set start values */
+			lowest = gstart;
+			highest = gend;
+		} else {
+			if (gstart < lowest)
+				lowest = gstart;
+			if (gend > highest)
+				highest = gend;
+		}
+	}
+	/* this gives the absolute number of pins */
+	npins = highest - lowest + 1;
+	return npins;
+}
+
+static int abx500_gpio_probe(struct platform_device *pdev)
+{
+	struct ab8500_platform_data *abx500_pdata =
+				dev_get_platdata(pdev->dev.parent);
+	struct abx500_gpio_platform_data *pdata;
+	struct abx500_pinctrl *pct;
+	const struct platform_device_id *platid = platform_get_device_id(pdev);
+	int ret;
+	int i;
+
+	pdata = abx500_pdata->gpio;
+	if (!pdata)	{
+		dev_err(&pdev->dev, "gpio platform data missing\n");
+		return -ENODEV;
+	}
+
+	pct = devm_kzalloc(&pdev->dev, sizeof(struct abx500_pinctrl),
+				   GFP_KERNEL);
+	if (pct == NULL) {
+		dev_err(&pdev->dev,
+			"failed to allocate memory for pct\n");
+		return -ENOMEM;
+	}
+
+	pct->dev = &pdev->dev;
+	pct->parent = dev_get_drvdata(pdev->dev.parent);
+	pct->chip = abx500gpio_chip;
+	pct->chip.dev = &pdev->dev;
+	pct->chip.base = pdata->gpio_base;
+	pct->irq_base = pdata->irq_base;
+
+	/* initialize the lock */
+	mutex_init(&pct->lock);
+
+	/* Poke in other ASIC variants here */
+	switch (platid->driver_data) {
+	default:
+		dev_err(&pdev->dev, "Unsupported pinctrl sub driver (%d)\n",
+				(int) platid->driver_data);
+		return -EINVAL;
+	}
+
+	if (!pct->soc) {
+		dev_err(&pdev->dev, "Invalid SOC data\n");
+		return -EINVAL;
+	}
+
+	pct->chip.ngpio = abx500_get_gpio_num(pct->soc);
+	pct->irq_cluster = pct->soc->gpio_irq_cluster;
+	pct->irq_cluster_size = pct->soc->ngpio_irq_cluster;
+	pct->irq_gpio_rising_offset = pct->soc->irq_gpio_rising_offset;
+	pct->irq_gpio_falling_offset = pct->soc->irq_gpio_falling_offset;
+	pct->irq_gpio_factor = pct->soc->irq_gpio_factor;
+
+	ret = abx500_gpio_irq_init(pct);
+	if (ret)
+		goto out_free;
+	ret = gpiochip_add(&pct->chip);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to add gpiochip: %d\n",
+				ret);
+		goto out_rem_irq;
+	}
+	dev_info(&pdev->dev, "added gpiochip\n");
+
+	abx500_pinctrl_desc.pins = pct->soc->pins;
+	abx500_pinctrl_desc.npins = pct->soc->npins;
+	pct->pctldev = pinctrl_register(&abx500_pinctrl_desc, &pdev->dev, pct);
+	if (!pct->pctldev) {
+		dev_err(&pdev->dev,
+			"could not register abx500 pinctrl driver\n");
+		goto out_rem_chip;
+	}
+	dev_info(&pdev->dev, "registered pin controller\n");
+
+	/* We will handle a range of GPIO pins */
+	for (i = 0; i < pct->soc->gpio_num_ranges; i++) {
+		const struct abx500_pinrange *p = &pct->soc->gpio_ranges[i];
+
+		ret = gpiochip_add_pin_range(&pct->chip,
+					dev_name(&pdev->dev),
+					p->offset - 1, p->offset, p->npins);
+		if (ret < 0)
+			return ret;
+	}
+
+	platform_set_drvdata(pdev, pct);
+	dev_info(&pdev->dev, "initialized abx500 pinctrl driver\n");
+
+	return 0;
+
+out_rem_chip:
+	ret = gpiochip_remove(&pct->chip);
+	if (ret)
+		dev_info(&pdev->dev, "failed to remove gpiochip\n");
+out_rem_irq:
+	abx500_gpio_irq_remove(pct);
+out_free:
+	mutex_destroy(&pct->lock);
+	return ret;
+}
+
+/*
+ * abx500_gpio_remove() - remove Ab8500-gpio driver
+ * @pdev :	Platform device registered
+ */
+static int abx500_gpio_remove(struct platform_device *pdev)
+{
+	struct abx500_pinctrl *pct = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = gpiochip_remove(&pct->chip);
+	if (ret < 0) {
+		dev_err(pct->dev, "unable to remove gpiochip: %d\n",
+			ret);
+		return ret;
+	}
+
+	mutex_destroy(&pct->lock);
+
+	return 0;
+}
+
+static const struct platform_device_id abx500_pinctrl_id[] = {
+	{ "pinctrl-ab8500", PINCTRL_AB8500 },
+	{ "pinctrl-ab8540", PINCTRL_AB8540 },
+	{ "pinctrl-ab9540", PINCTRL_AB9540 },
+	{ "pinctrl-ab8505", PINCTRL_AB8505 },
+	{ },
+};
+
+static struct platform_driver abx500_gpio_driver = {
+	.driver = {
+		.name = "abx500-gpio",
+		.owner = THIS_MODULE,
+	},
+	.probe = abx500_gpio_probe,
+	.remove = abx500_gpio_remove,
+	.id_table = abx500_pinctrl_id,
+};
+
+static int __init abx500_gpio_init(void)
+{
+	return platform_driver_register(&abx500_gpio_driver);
+}
+core_initcall(abx500_gpio_init);
+
+MODULE_AUTHOR("Patrice Chotard <patrice.chotard@st.com>");
+MODULE_DESCRIPTION("Driver allows to use AxB5xx unused pins to be used as GPIO");
+MODULE_ALIAS("platform:abx500-gpio");
+MODULE_LICENSE("GPL v2");