// SPDX-License-Identifier: GPL-2.0
/*
 * Driver for STMicroelectronics Multi-Function eXpander (STMFX) GPIO expander
 *
 * Copyright (C) 2019 STMicroelectronics
 * Author(s): Amelie Delaunay <amelie.delaunay@st.com>.
 */
#include <linux/gpio/driver.h>
#include <linux/interrupt.h>
#include <linux/mfd/stmfx.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/seq_file.h>
#include <linux/string_choices.h>

#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinmux.h>

#include "core.h"
#include "pinctrl-utils.h"

/* GPIOs expander */
/* GPIO_STATE1 0x10, GPIO_STATE2 0x11, GPIO_STATE3 0x12 */
#define STMFX_REG_GPIO_STATE            STMFX_REG_GPIO_STATE1 /* R */
/* GPIO_DIR1 0x60, GPIO_DIR2 0x61, GPIO_DIR3 0x63 */
#define STMFX_REG_GPIO_DIR              STMFX_REG_GPIO_DIR1 /* RW */
/* GPIO_TYPE1 0x64, GPIO_TYPE2 0x65, GPIO_TYPE3 0x66 */
#define STMFX_REG_GPIO_TYPE             STMFX_REG_GPIO_TYPE1 /* RW */
/* GPIO_PUPD1 0x68, GPIO_PUPD2 0x69, GPIO_PUPD3 0x6A */
#define STMFX_REG_GPIO_PUPD             STMFX_REG_GPIO_PUPD1 /* RW */
/* GPO_SET1 0x6C, GPO_SET2 0x6D, GPO_SET3 0x6E */
#define STMFX_REG_GPO_SET               STMFX_REG_GPO_SET1 /* RW */
/* GPO_CLR1 0x70, GPO_CLR2 0x71, GPO_CLR3 0x72 */
#define STMFX_REG_GPO_CLR               STMFX_REG_GPO_CLR1 /* RW */
/* IRQ_GPI_SRC1 0x48, IRQ_GPI_SRC2 0x49, IRQ_GPI_SRC3 0x4A */
#define STMFX_REG_IRQ_GPI_SRC           STMFX_REG_IRQ_GPI_SRC1 /* RW */
/* IRQ_GPI_EVT1 0x4C, IRQ_GPI_EVT2 0x4D, IRQ_GPI_EVT3 0x4E */
#define STMFX_REG_IRQ_GPI_EVT           STMFX_REG_IRQ_GPI_EVT1 /* RW */
/* IRQ_GPI_TYPE1 0x50, IRQ_GPI_TYPE2 0x51, IRQ_GPI_TYPE3 0x52 */
#define STMFX_REG_IRQ_GPI_TYPE          STMFX_REG_IRQ_GPI_TYPE1 /* RW */
/* IRQ_GPI_PENDING1 0x0C, IRQ_GPI_PENDING2 0x0D, IRQ_GPI_PENDING3 0x0E*/
#define STMFX_REG_IRQ_GPI_PENDING       STMFX_REG_IRQ_GPI_PENDING1 /* R */
/* IRQ_GPI_ACK1 0x54, IRQ_GPI_ACK2 0x55, IRQ_GPI_ACK3 0x56 */
#define STMFX_REG_IRQ_GPI_ACK           STMFX_REG_IRQ_GPI_ACK1 /* RW */

#define NR_GPIO_REGS                    3
#define NR_GPIOS_PER_REG                8
#define get_reg(offset)                 ((offset) / NR_GPIOS_PER_REG)
#define get_shift(offset)               ((offset) % NR_GPIOS_PER_REG)
#define get_mask(offset)                (BIT(get_shift(offset)))

/*
 * STMFX pinctrl can have up to 24 pins if STMFX other functions are not used.
 * Pins availability is managed thanks to gpio-ranges property.
 */
static const struct pinctrl_pin_desc stmfx_pins[] = {
        PINCTRL_PIN(0, "gpio0"),
        PINCTRL_PIN(1, "gpio1"),
        PINCTRL_PIN(2, "gpio2"),
        PINCTRL_PIN(3, "gpio3"),
        PINCTRL_PIN(4, "gpio4"),
        PINCTRL_PIN(5, "gpio5"),
        PINCTRL_PIN(6, "gpio6"),
        PINCTRL_PIN(7, "gpio7"),
        PINCTRL_PIN(8, "gpio8"),
        PINCTRL_PIN(9, "gpio9"),
        PINCTRL_PIN(10, "gpio10"),
        PINCTRL_PIN(11, "gpio11"),
        PINCTRL_PIN(12, "gpio12"),
        PINCTRL_PIN(13, "gpio13"),
        PINCTRL_PIN(14, "gpio14"),
        PINCTRL_PIN(15, "gpio15"),
        PINCTRL_PIN(16, "agpio0"),
        PINCTRL_PIN(17, "agpio1"),
        PINCTRL_PIN(18, "agpio2"),
        PINCTRL_PIN(19, "agpio3"),
        PINCTRL_PIN(20, "agpio4"),
        PINCTRL_PIN(21, "agpio5"),
        PINCTRL_PIN(22, "agpio6"),
        PINCTRL_PIN(23, "agpio7"),
};

struct stmfx_pinctrl {
        struct device *dev;
        struct stmfx *stmfx;
        struct pinctrl_dev *pctl_dev;
        struct pinctrl_desc pctl_desc;
        struct gpio_chip gpio_chip;
        struct mutex lock; /* IRQ bus lock */
        unsigned long gpio_valid_mask;
        /* Cache of IRQ_GPI_* registers for bus_lock */
        u8 irq_gpi_src[NR_GPIO_REGS];
        u8 irq_gpi_type[NR_GPIO_REGS];
        u8 irq_gpi_evt[NR_GPIO_REGS];
        u8 irq_toggle_edge[NR_GPIO_REGS];
#ifdef CONFIG_PM
        /* Backup of GPIO_* registers for suspend/resume */
        u8 bkp_gpio_state[NR_GPIO_REGS];
        u8 bkp_gpio_dir[NR_GPIO_REGS];
        u8 bkp_gpio_type[NR_GPIO_REGS];
        u8 bkp_gpio_pupd[NR_GPIO_REGS];
#endif
};

static int stmfx_gpio_get(struct gpio_chip *gc, unsigned int offset)
{
        struct stmfx_pinctrl *pctl = gpiochip_get_data(gc);
        u32 reg = STMFX_REG_GPIO_STATE + get_reg(offset);
        u32 mask = get_mask(offset);
        u32 value;
        int ret;

        ret = regmap_read(pctl->stmfx->map, reg, &value);

        return ret ? ret : !!(value & mask);
}

static int stmfx_gpio_set(struct gpio_chip *gc, unsigned int offset, int value)
{
        struct stmfx_pinctrl *pctl = gpiochip_get_data(gc);
        u32 reg = value ? STMFX_REG_GPO_SET : STMFX_REG_GPO_CLR;
        u32 mask = get_mask(offset);

        return regmap_write_bits(pctl->stmfx->map, reg + get_reg(offset),
                                 mask, mask);
}

static int stmfx_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
{
        struct stmfx_pinctrl *pctl = gpiochip_get_data(gc);
        u32 reg = STMFX_REG_GPIO_DIR + get_reg(offset);
        u32 mask = get_mask(offset);
        u32 val;
        int ret;

        ret = regmap_read(pctl->stmfx->map, reg, &val);
        /*
         * On stmfx, gpio pins direction is (0)input, (1)output.
         */
        if (ret)
                return ret;

        if (val & mask)
                return GPIO_LINE_DIRECTION_OUT;

        return GPIO_LINE_DIRECTION_IN;
}

static int stmfx_gpio_direction_input(struct gpio_chip *gc, unsigned int offset)
{
        struct stmfx_pinctrl *pctl = gpiochip_get_data(gc);
        u32 reg = STMFX_REG_GPIO_DIR + get_reg(offset);
        u32 mask = get_mask(offset);

        return regmap_write_bits(pctl->stmfx->map, reg, mask, 0);
}

static int stmfx_gpio_direction_output(struct gpio_chip *gc,
                                       unsigned int offset, int value)
{
        struct stmfx_pinctrl *pctl = gpiochip_get_data(gc);
        u32 reg = STMFX_REG_GPIO_DIR + get_reg(offset);
        u32 mask = get_mask(offset);
        int ret;

        ret = stmfx_gpio_set(gc, offset, value);
        if (ret)
                return ret;

        return regmap_write_bits(pctl->stmfx->map, reg, mask, mask);
}

static int stmfx_pinconf_get_pupd(struct stmfx_pinctrl *pctl,
                                  unsigned int offset)
{
        u32 reg = STMFX_REG_GPIO_PUPD + get_reg(offset);
        u32 pupd, mask = get_mask(offset);
        int ret;

        ret = regmap_read(pctl->stmfx->map, reg, &pupd);
        if (ret)
                return ret;

        return !!(pupd & mask);
}

static int stmfx_pinconf_set_pupd(struct stmfx_pinctrl *pctl,
                                  unsigned int offset, u32 pupd)
{
        u32 reg = STMFX_REG_GPIO_PUPD + get_reg(offset);
        u32 mask = get_mask(offset);

        return regmap_write_bits(pctl->stmfx->map, reg, mask, pupd ? mask : 0);
}

static int stmfx_pinconf_get_type(struct stmfx_pinctrl *pctl,
                                  unsigned int offset)
{
        u32 reg = STMFX_REG_GPIO_TYPE + get_reg(offset);
        u32 type, mask = get_mask(offset);
        int ret;

        ret = regmap_read(pctl->stmfx->map, reg, &type);
        if (ret)
                return ret;

        return !!(type & mask);
}

static int stmfx_pinconf_set_type(struct stmfx_pinctrl *pctl,
                                  unsigned int offset, u32 type)
{
        u32 reg = STMFX_REG_GPIO_TYPE + get_reg(offset);
        u32 mask = get_mask(offset);

        return regmap_write_bits(pctl->stmfx->map, reg, mask, type ? mask : 0);
}

static int stmfx_pinconf_get(struct pinctrl_dev *pctldev,
                             unsigned int pin, unsigned long *config)
{
        struct stmfx_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
        u32 param = pinconf_to_config_param(*config);
        struct pinctrl_gpio_range *range;
        u32 arg = 0;
        int ret, dir, type, pupd;

        range = pinctrl_find_gpio_range_from_pin_nolock(pctldev, pin);
        if (!range)
                return -EINVAL;

        dir = stmfx_gpio_get_direction(&pctl->gpio_chip, pin);
        if (dir < 0)
                return dir;

        /*
         * Currently the gpiolib IN is 1 and OUT is 0 but let's not count
         * on it just to be on the safe side also in the future :)
         */
        dir = (dir == GPIO_LINE_DIRECTION_IN) ? 1 : 0;

        type = stmfx_pinconf_get_type(pctl, pin);
        if (type < 0)
                return type;
        pupd = stmfx_pinconf_get_pupd(pctl, pin);
        if (pupd < 0)
                return pupd;

        switch (param) {
        case PIN_CONFIG_BIAS_DISABLE:
                if ((!dir && (!type || !pupd)) || (dir && !type))
                        arg = 1;
                break;
        case PIN_CONFIG_BIAS_PULL_DOWN:
                if (dir && type && !pupd)
                        arg = 1;
                break;
        case PIN_CONFIG_BIAS_PULL_UP:
                if (type && pupd)
                        arg = 1;
                break;
        case PIN_CONFIG_DRIVE_OPEN_DRAIN:
                if ((!dir && type) || (dir && !type))
                        arg = 1;
                break;
        case PIN_CONFIG_DRIVE_PUSH_PULL:
                if ((!dir && !type) || (dir && type))
                        arg = 1;
                break;
        case PIN_CONFIG_LEVEL:
                if (dir)
                        return -EINVAL;

                ret = stmfx_gpio_get(&pctl->gpio_chip, pin);
                if (ret < 0)
                        return ret;

                arg = ret;
                break;
        default:
                return -ENOTSUPP;
        }

        *config = pinconf_to_config_packed(param, arg);

        return 0;
}

static int stmfx_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
                             unsigned long *configs, unsigned int num_configs)
{
        struct stmfx_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
        struct pinctrl_gpio_range *range;
        enum pin_config_param param;
        u32 arg;
        int i, ret;

        range = pinctrl_find_gpio_range_from_pin_nolock(pctldev, pin);
        if (!range) {
                dev_err(pctldev->dev, "pin %d is not available\n", pin);
                return -EINVAL;
        }

        for (i = 0; i < num_configs; i++) {
                param = pinconf_to_config_param(configs[i]);
                arg = pinconf_to_config_argument(configs[i]);

                switch (param) {
                case PIN_CONFIG_BIAS_PULL_PIN_DEFAULT:
                case PIN_CONFIG_BIAS_DISABLE:
                case PIN_CONFIG_DRIVE_PUSH_PULL:
                        ret = stmfx_pinconf_set_type(pctl, pin, 0);
                        if (ret)
                                return ret;
                        break;
                case PIN_CONFIG_BIAS_PULL_DOWN:
                        ret = stmfx_pinconf_set_type(pctl, pin, 1);
                        if (ret)
                                return ret;
                        ret = stmfx_pinconf_set_pupd(pctl, pin, 0);
                        if (ret)
                                return ret;
                        break;
                case PIN_CONFIG_BIAS_PULL_UP:
                        ret = stmfx_pinconf_set_type(pctl, pin, 1);
                        if (ret)
                                return ret;
                        ret = stmfx_pinconf_set_pupd(pctl, pin, 1);
                        if (ret)
                                return ret;
                        break;
                case PIN_CONFIG_DRIVE_OPEN_DRAIN:
                        ret = stmfx_pinconf_set_type(pctl, pin, 1);
                        if (ret)
                                return ret;
                        break;
                case PIN_CONFIG_LEVEL:
                        ret = stmfx_gpio_direction_output(&pctl->gpio_chip,
                                                          pin, arg);
                        if (ret)
                                return ret;
                        break;
                default:
                        return -ENOTSUPP;
                }
        }

        return 0;
}

static void stmfx_pinconf_dbg_show(struct pinctrl_dev *pctldev,
                                   struct seq_file *s, unsigned int offset)
{
        struct stmfx_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
        struct pinctrl_gpio_range *range;
        int dir, type, pupd, val;

        range = pinctrl_find_gpio_range_from_pin_nolock(pctldev, offset);
        if (!range)
                return;

        dir = stmfx_gpio_get_direction(&pctl->gpio_chip, offset);
        if (dir < 0)
                return;
        type = stmfx_pinconf_get_type(pctl, offset);
        if (type < 0)
                return;
        pupd = stmfx_pinconf_get_pupd(pctl, offset);
        if (pupd < 0)
                return;
        val = stmfx_gpio_get(&pctl->gpio_chip, offset);
        if (val < 0)
                return;

        if (dir == GPIO_LINE_DIRECTION_OUT) {
                seq_printf(s, "output %s ", str_high_low(val));
                if (type)
                        seq_printf(s, "open drain %s internal pull-up ",
                                   pupd ? "with" : "without");
                else
                        seq_puts(s, "push pull no pull ");
        } else {
                seq_printf(s, "input %s ", str_high_low(val));
                if (type)
                        seq_printf(s, "with internal pull-%s ",
                                   str_up_down(pupd));
                else
                        seq_printf(s, "%s ", pupd ? "floating" : "analog");
        }
}

static const struct pinconf_ops stmfx_pinconf_ops = {
        .pin_config_get         = stmfx_pinconf_get,
        .pin_config_set         = stmfx_pinconf_set,
        .pin_config_dbg_show    = stmfx_pinconf_dbg_show,
};

static int stmfx_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
{
        return 0;
}

static const char *stmfx_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
                                                unsigned int selector)
{
        return NULL;
}

static int stmfx_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
                                        unsigned int selector,
                                        const unsigned int **pins,
                                        unsigned int *num_pins)
{
        return -ENOTSUPP;
}

static const struct pinctrl_ops stmfx_pinctrl_ops = {
        .get_groups_count = stmfx_pinctrl_get_groups_count,
        .get_group_name = stmfx_pinctrl_get_group_name,
        .get_group_pins = stmfx_pinctrl_get_group_pins,
        .dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
        .dt_free_map = pinctrl_utils_free_map,
};

static void stmfx_pinctrl_irq_mask(struct irq_data *data)
{
        struct gpio_chip *gpio_chip = irq_data_get_irq_chip_data(data);
        struct stmfx_pinctrl *pctl = gpiochip_get_data(gpio_chip);
        u32 reg = get_reg(data->hwirq);
        u32 mask = get_mask(data->hwirq);

        pctl->irq_gpi_src[reg] &= ~mask;
        gpiochip_disable_irq(gpio_chip, irqd_to_hwirq(data));
}

static void stmfx_pinctrl_irq_unmask(struct irq_data *data)
{
        struct gpio_chip *gpio_chip = irq_data_get_irq_chip_data(data);
        struct stmfx_pinctrl *pctl = gpiochip_get_data(gpio_chip);
        u32 reg = get_reg(data->hwirq);
        u32 mask = get_mask(data->hwirq);

        gpiochip_enable_irq(gpio_chip, irqd_to_hwirq(data));
        pctl->irq_gpi_src[reg] |= mask;
}

static int stmfx_pinctrl_irq_set_type(struct irq_data *data, unsigned int type)
{
        struct gpio_chip *gpio_chip = irq_data_get_irq_chip_data(data);
        struct stmfx_pinctrl *pctl = gpiochip_get_data(gpio_chip);
        u32 reg = get_reg(data->hwirq);
        u32 mask = get_mask(data->hwirq);

        if (type == IRQ_TYPE_NONE)
                return -EINVAL;

        if (type & IRQ_TYPE_EDGE_BOTH) {
                pctl->irq_gpi_evt[reg] |= mask;
                irq_set_handler_locked(data, handle_edge_irq);
        } else {
                pctl->irq_gpi_evt[reg] &= ~mask;
                irq_set_handler_locked(data, handle_level_irq);
        }

        if ((type & IRQ_TYPE_EDGE_RISING) || (type & IRQ_TYPE_LEVEL_HIGH))
                pctl->irq_gpi_type[reg] |= mask;
        else
                pctl->irq_gpi_type[reg] &= ~mask;

        /*
         * In case of (type & IRQ_TYPE_EDGE_BOTH), we need to know current
         * GPIO value to set the right edge trigger. But in atomic context
         * here we can't access registers over I2C. That's why (type &
         * IRQ_TYPE_EDGE_BOTH) will be managed in .irq_sync_unlock.
         */

        if ((type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH)
                pctl->irq_toggle_edge[reg] |= mask;
        else
                pctl->irq_toggle_edge[reg] &= mask;

        return 0;
}

static void stmfx_pinctrl_irq_bus_lock(struct irq_data *data)
{
        struct gpio_chip *gpio_chip = irq_data_get_irq_chip_data(data);
        struct stmfx_pinctrl *pctl = gpiochip_get_data(gpio_chip);

        mutex_lock(&pctl->lock);
}

static void stmfx_pinctrl_irq_bus_sync_unlock(struct irq_data *data)
{
        struct gpio_chip *gpio_chip = irq_data_get_irq_chip_data(data);
        struct stmfx_pinctrl *pctl = gpiochip_get_data(gpio_chip);
        u32 reg = get_reg(data->hwirq);
        u32 mask = get_mask(data->hwirq);

        /*
         * In case of IRQ_TYPE_EDGE_BOTH), read the current GPIO value
         * (this couldn't be done in .irq_set_type because of atomic context)
         * to set the right irq trigger type.
         */
        if (pctl->irq_toggle_edge[reg] & mask) {
                if (stmfx_gpio_get(gpio_chip, data->hwirq))
                        pctl->irq_gpi_type[reg] &= ~mask;
                else
                        pctl->irq_gpi_type[reg] |= mask;
        }

        regmap_bulk_write(pctl->stmfx->map, STMFX_REG_IRQ_GPI_EVT,
                          pctl->irq_gpi_evt, NR_GPIO_REGS);
        regmap_bulk_write(pctl->stmfx->map, STMFX_REG_IRQ_GPI_TYPE,
                          pctl->irq_gpi_type, NR_GPIO_REGS);
        regmap_bulk_write(pctl->stmfx->map, STMFX_REG_IRQ_GPI_SRC,
                          pctl->irq_gpi_src, NR_GPIO_REGS);

        mutex_unlock(&pctl->lock);
}

static int stmfx_gpio_irq_request_resources(struct irq_data *data)
{
        struct gpio_chip *gpio_chip = irq_data_get_irq_chip_data(data);
        int ret;

        ret = stmfx_gpio_direction_input(gpio_chip, data->hwirq);
        if (ret)
                return ret;

        return gpiochip_reqres_irq(gpio_chip, data->hwirq);
}

static void stmfx_gpio_irq_release_resources(struct irq_data *data)
{
        struct gpio_chip *gpio_chip = irq_data_get_irq_chip_data(data);

        return gpiochip_relres_irq(gpio_chip, data->hwirq);
}

static void stmfx_pinctrl_irq_toggle_trigger(struct stmfx_pinctrl *pctl,
                                             unsigned int offset)
{
        u32 reg = get_reg(offset);
        u32 mask = get_mask(offset);
        int val;

        if (!(pctl->irq_toggle_edge[reg] & mask))
                return;

        val = stmfx_gpio_get(&pctl->gpio_chip, offset);
        if (val < 0)
                return;

        if (val) {
                pctl->irq_gpi_type[reg] &= mask;
                regmap_write_bits(pctl->stmfx->map,
                                  STMFX_REG_IRQ_GPI_TYPE + reg,
                                  mask, 0);

        } else {
                pctl->irq_gpi_type[reg] |= mask;
                regmap_write_bits(pctl->stmfx->map,
                                  STMFX_REG_IRQ_GPI_TYPE + reg,
                                  mask, mask);
        }
}

static irqreturn_t stmfx_pinctrl_irq_thread_fn(int irq, void *dev_id)
{
        struct stmfx_pinctrl *pctl = (struct stmfx_pinctrl *)dev_id;
        struct gpio_chip *gc = &pctl->gpio_chip;
        u8 pending[NR_GPIO_REGS];
        u8 src[NR_GPIO_REGS] = {0, 0, 0};
        unsigned long n, status;
        int i, ret;

        ret = regmap_bulk_read(pctl->stmfx->map, STMFX_REG_IRQ_GPI_PENDING,
                               &pending, NR_GPIO_REGS);
        if (ret)
                return IRQ_NONE;

        regmap_bulk_write(pctl->stmfx->map, STMFX_REG_IRQ_GPI_SRC,
                          src, NR_GPIO_REGS);

        BUILD_BUG_ON(NR_GPIO_REGS > sizeof(status));
        for (i = 0, status = 0; i < NR_GPIO_REGS; i++)
                status |= (unsigned long)pending[i] << (i * 8);
        for_each_set_bit(n, &status, gc->ngpio) {
                handle_nested_irq(irq_find_mapping(gc->irq.domain, n));
                stmfx_pinctrl_irq_toggle_trigger(pctl, n);
        }

        regmap_bulk_write(pctl->stmfx->map, STMFX_REG_IRQ_GPI_SRC,
                          pctl->irq_gpi_src, NR_GPIO_REGS);

        return IRQ_HANDLED;
}

static void stmfx_pinctrl_irq_print_chip(struct irq_data *d, struct seq_file *p)
{
        struct gpio_chip *gpio_chip = irq_data_get_irq_chip_data(d);
        struct stmfx_pinctrl *pctl = gpiochip_get_data(gpio_chip);

        seq_puts(p, dev_name(pctl->dev));
}

static const struct irq_chip stmfx_pinctrl_irq_chip = {
        .irq_mask = stmfx_pinctrl_irq_mask,
        .irq_unmask = stmfx_pinctrl_irq_unmask,
        .irq_set_type = stmfx_pinctrl_irq_set_type,
        .irq_bus_lock = stmfx_pinctrl_irq_bus_lock,
        .irq_bus_sync_unlock = stmfx_pinctrl_irq_bus_sync_unlock,
        .irq_request_resources = stmfx_gpio_irq_request_resources,
        .irq_release_resources = stmfx_gpio_irq_release_resources,
        .irq_print_chip = stmfx_pinctrl_irq_print_chip,
        .flags = IRQCHIP_IMMUTABLE,
};

static int stmfx_pinctrl_gpio_function_enable(struct stmfx_pinctrl *pctl)
{
        struct pinctrl_gpio_range *gpio_range;
        struct pinctrl_dev *pctl_dev = pctl->pctl_dev;
        u32 func = STMFX_FUNC_GPIO;

        pctl->gpio_valid_mask = GENMASK(15, 0);

        gpio_range = pinctrl_find_gpio_range_from_pin(pctl_dev, 16);
        if (gpio_range) {
                func |= STMFX_FUNC_ALTGPIO_LOW;
                pctl->gpio_valid_mask |= GENMASK(19, 16);
        }

        gpio_range = pinctrl_find_gpio_range_from_pin(pctl_dev, 20);
        if (gpio_range) {
                func |= STMFX_FUNC_ALTGPIO_HIGH;
                pctl->gpio_valid_mask |= GENMASK(23, 20);
        }

        return stmfx_function_enable(pctl->stmfx, func);
}

static int stmfx_pinctrl_probe(struct platform_device *pdev)
{
        struct stmfx *stmfx = dev_get_drvdata(pdev->dev.parent);
        struct device_node *np = pdev->dev.of_node;
        struct stmfx_pinctrl *pctl;
        struct gpio_irq_chip *girq;
        int irq, ret;

        pctl = devm_kzalloc(stmfx->dev, sizeof(*pctl), GFP_KERNEL);
        if (!pctl)
                return -ENOMEM;

        platform_set_drvdata(pdev, pctl);

        pctl->dev = &pdev->dev;
        pctl->stmfx = stmfx;

        if (!of_property_present(np, "gpio-ranges")) {
                dev_err(pctl->dev, "missing required gpio-ranges property\n");
                return -EINVAL;
        }

        irq = platform_get_irq(pdev, 0);
        if (irq < 0)
                return irq;

        mutex_init(&pctl->lock);

        /* Register pin controller */
        pctl->pctl_desc.name = "stmfx-pinctrl";
        pctl->pctl_desc.pctlops = &stmfx_pinctrl_ops;
        pctl->pctl_desc.confops = &stmfx_pinconf_ops;
        pctl->pctl_desc.pins = stmfx_pins;
        pctl->pctl_desc.npins = ARRAY_SIZE(stmfx_pins);
        pctl->pctl_desc.owner = THIS_MODULE;
        pctl->pctl_desc.link_consumers = true;

        ret = devm_pinctrl_register_and_init(pctl->dev, &pctl->pctl_desc,
                                             pctl, &pctl->pctl_dev);
        if (ret) {
                dev_err(pctl->dev, "pinctrl registration failed\n");
                return ret;
        }

        ret = pinctrl_enable(pctl->pctl_dev);
        if (ret) {
                dev_err(pctl->dev, "pinctrl enable failed\n");
                return ret;
        }

        /* Register gpio controller */
        pctl->gpio_chip.label = "stmfx-gpio";
        pctl->gpio_chip.parent = pctl->dev;
        pctl->gpio_chip.get_direction = stmfx_gpio_get_direction;
        pctl->gpio_chip.direction_input = stmfx_gpio_direction_input;
        pctl->gpio_chip.direction_output = stmfx_gpio_direction_output;
        pctl->gpio_chip.get = stmfx_gpio_get;
        pctl->gpio_chip.set = stmfx_gpio_set;
        pctl->gpio_chip.set_config = gpiochip_generic_config;
        pctl->gpio_chip.base = -1;
        pctl->gpio_chip.ngpio = pctl->pctl_desc.npins;
        pctl->gpio_chip.can_sleep = true;

        girq = &pctl->gpio_chip.irq;
        gpio_irq_chip_set_chip(girq, &stmfx_pinctrl_irq_chip);
        /* This will let us handle the parent IRQ in the driver */
        girq->parent_handler = NULL;
        girq->num_parents = 0;
        girq->parents = NULL;
        girq->default_type = IRQ_TYPE_NONE;
        girq->handler = handle_bad_irq;
        girq->threaded = true;

        ret = devm_gpiochip_add_data(pctl->dev, &pctl->gpio_chip, pctl);
        if (ret) {
                dev_err(pctl->dev, "gpio_chip registration failed\n");
                return ret;
        }

        ret = stmfx_pinctrl_gpio_function_enable(pctl);
        if (ret)
                return ret;

        ret = devm_request_threaded_irq(pctl->dev, irq, NULL,
                                        stmfx_pinctrl_irq_thread_fn,
                                        IRQF_ONESHOT,
                                        dev_name(pctl->dev), pctl);
        if (ret) {
                dev_err(pctl->dev, "cannot request irq%d\n", irq);
                return ret;
        }

        dev_info(pctl->dev,
                 "%ld GPIOs available\n", hweight_long(pctl->gpio_valid_mask));

        return 0;
}

static void stmfx_pinctrl_remove(struct platform_device *pdev)
{
        struct stmfx *stmfx = dev_get_drvdata(pdev->dev.parent);
        int ret;

        ret = stmfx_function_disable(stmfx,
                                     STMFX_FUNC_GPIO |
                                     STMFX_FUNC_ALTGPIO_LOW |
                                     STMFX_FUNC_ALTGPIO_HIGH);
        if (ret)
                dev_err(&pdev->dev, "Failed to disable pins (%pe)\n",
                        ERR_PTR(ret));
}

#ifdef CONFIG_PM_SLEEP
static int stmfx_pinctrl_backup_regs(struct stmfx_pinctrl *pctl)
{
        int ret;

        ret = regmap_bulk_read(pctl->stmfx->map, STMFX_REG_GPIO_STATE,
                               &pctl->bkp_gpio_state, NR_GPIO_REGS);
        if (ret)
                return ret;
        ret = regmap_bulk_read(pctl->stmfx->map, STMFX_REG_GPIO_DIR,
                               &pctl->bkp_gpio_dir, NR_GPIO_REGS);
        if (ret)
                return ret;
        ret = regmap_bulk_read(pctl->stmfx->map, STMFX_REG_GPIO_TYPE,
                               &pctl->bkp_gpio_type, NR_GPIO_REGS);
        if (ret)
                return ret;
        ret = regmap_bulk_read(pctl->stmfx->map, STMFX_REG_GPIO_PUPD,
                               &pctl->bkp_gpio_pupd, NR_GPIO_REGS);
        if (ret)
                return ret;

        return 0;
}

static int stmfx_pinctrl_restore_regs(struct stmfx_pinctrl *pctl)
{
        int ret;

        ret = regmap_bulk_write(pctl->stmfx->map, STMFX_REG_GPIO_DIR,
                                pctl->bkp_gpio_dir, NR_GPIO_REGS);
        if (ret)
                return ret;
        ret = regmap_bulk_write(pctl->stmfx->map, STMFX_REG_GPIO_TYPE,
                                pctl->bkp_gpio_type, NR_GPIO_REGS);
        if (ret)
                return ret;
        ret = regmap_bulk_write(pctl->stmfx->map, STMFX_REG_GPIO_PUPD,
                                pctl->bkp_gpio_pupd, NR_GPIO_REGS);
        if (ret)
                return ret;
        ret = regmap_bulk_write(pctl->stmfx->map, STMFX_REG_GPO_SET,
                                pctl->bkp_gpio_state, NR_GPIO_REGS);
        if (ret)
                return ret;
        ret = regmap_bulk_write(pctl->stmfx->map, STMFX_REG_IRQ_GPI_EVT,
                                pctl->irq_gpi_evt, NR_GPIO_REGS);
        if (ret)
                return ret;
        ret = regmap_bulk_write(pctl->stmfx->map, STMFX_REG_IRQ_GPI_TYPE,
                                pctl->irq_gpi_type, NR_GPIO_REGS);
        if (ret)
                return ret;
        ret = regmap_bulk_write(pctl->stmfx->map, STMFX_REG_IRQ_GPI_SRC,
                                pctl->irq_gpi_src, NR_GPIO_REGS);
        if (ret)
                return ret;

        return 0;
}

static int stmfx_pinctrl_suspend(struct device *dev)
{
        struct stmfx_pinctrl *pctl = dev_get_drvdata(dev);
        int ret;

        ret = stmfx_pinctrl_backup_regs(pctl);
        if (ret) {
                dev_err(pctl->dev, "registers backup failure\n");
                return ret;
        }

        return 0;
}

static int stmfx_pinctrl_resume(struct device *dev)
{
        struct stmfx_pinctrl *pctl = dev_get_drvdata(dev);
        int ret;

        ret = stmfx_pinctrl_restore_regs(pctl);
        if (ret) {
                dev_err(pctl->dev, "registers restoration failure\n");
                return ret;
        }

        return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(stmfx_pinctrl_dev_pm_ops,
                         stmfx_pinctrl_suspend, stmfx_pinctrl_resume);

static const struct of_device_id stmfx_pinctrl_of_match[] = {
        { .compatible = "st,stmfx-0300-pinctrl", },
        {},
};
MODULE_DEVICE_TABLE(of, stmfx_pinctrl_of_match);

static struct platform_driver stmfx_pinctrl_driver = {
        .driver = {
                .name = "stmfx-pinctrl",
                .of_match_table = stmfx_pinctrl_of_match,
                .pm = &stmfx_pinctrl_dev_pm_ops,
        },
        .probe = stmfx_pinctrl_probe,
        .remove = stmfx_pinctrl_remove,
};
module_platform_driver(stmfx_pinctrl_driver);

MODULE_DESCRIPTION("STMFX pinctrl/GPIO driver");
MODULE_AUTHOR("Amelie Delaunay <amelie.delaunay@st.com>");
MODULE_LICENSE("GPL v2");