root/drivers/pinctrl/stm32/pinctrl-stm32.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) Maxime Coquelin 2015
 * Copyright (C) STMicroelectronics 2017
 * Author:  Maxime Coquelin <mcoquelin.stm32@gmail.com>
 *
 * Heavily based on Mediatek's pinctrl driver
 */
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/export.h>
#include <linux/gpio/driver.h>
#include <linux/hwspinlock.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/string_choices.h>

#include <linux/pinctrl/consumer.h>
#include <linux/pinctrl/machine.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinmux.h>

#include "../core.h"
#include "../pinconf.h"
#include "../pinctrl-utils.h"
#include "pinctrl-stm32.h"

#define STM32_GPIO_CID1         1

#define STM32_GPIO_MODER        0x00
#define STM32_GPIO_TYPER        0x04
#define STM32_GPIO_SPEEDR       0x08
#define STM32_GPIO_PUPDR        0x0c
#define STM32_GPIO_IDR          0x10
#define STM32_GPIO_ODR          0x14
#define STM32_GPIO_BSRR         0x18
#define STM32_GPIO_LCKR         0x1c
#define STM32_GPIO_AFRL         0x20
#define STM32_GPIO_AFRH         0x24
#define STM32_GPIO_SECCFGR      0x30
#define STM32_GPIO_DELAYRL      0x40
#define STM32_GPIO_ADVCFGRL     0x48
#define STM32_GPIO_CIDCFGR(x)   (0x50 + (0x8 * (x)))
#define STM32_GPIO_SEMCR(x)     (0x54 + (0x8 * (x)))

/* Unitary delay for STM32_GPIO_DELAYRL */
#define STM32_GPIO_DELAYRL_PS   250

#define STM32_GPIO_ADVCFGR_DLYPATH_MASK         BIT(0)
#define STM32_GPIO_ADVCFGR_DE_MASK              BIT(1)
#define STM32_GPIO_ADVCFGR_INVCLK_MASK          BIT(2)
#define STM32_GPIO_ADVCFGR_RET_MASK             BIT(3)
#define STM32_GPIO_ADVCFGR_IO_SYNC_MASK         \
        (STM32_GPIO_ADVCFGR_DE_MASK             \
         | STM32_GPIO_ADVCFGR_INVCLK_MASK       \
         | STM32_GPIO_ADVCFGR_RET_MASK)

#define STM32_GPIO_CIDCFGR_CFEN         BIT(0)
#define STM32_GPIO_CIDCFGR_SEMEN        BIT(1)
#define STM32_GPIO_CIDCFGR_SCID_MASK    GENMASK(5, 4)
#define STM32_GPIO_CIDCFGR_SEMWL_CID1   BIT(16 + STM32_GPIO_CID1)

#define STM32_GPIO_SEMCR_SEM_MUTEX      BIT(0)
#define STM32_GPIO_SEMCR_SEMCID_MASK    GENMASK(5, 4)

#define STM32_GPIO_PINS_PER_BANK 16
#define STM32_GPIO_IRQ_LINE      16

#define SYSCFG_IRQMUX_MASK GENMASK(3, 0)

/* Vendor specific pin configuration */
#define STM32_GPIO_PIN_CONFIG_IO_SYNC   (PIN_CONFIG_END + 1)

#define gpio_range_to_bank(chip) \
                container_of(chip, struct stm32_gpio_bank, range)

#define HWSPNLCK_TIMEOUT        1000 /* usec */

static const char * const stm32_gpio_functions[] = {
        "gpio", "af0", "af1",
        "af2", "af3", "af4",
        "af5", "af6", "af7",
        "af8", "af9", "af10",
        "af11", "af12", "af13",
        "af14", "af15", "analog",
        "reserved",
};

static const char * const stm32_gpio_io_sync[] = {
        "pass-through",
        "clock inverted",
        "data on rising edge",
        "data on falling edge",
        "data on both edges",
};

static u8 io_sync_2_advcfgr[] = {
        /* data or clock GPIO pass-through */
        [0] = 0,
        /* clock GPIO inverted */
        [1] = STM32_GPIO_ADVCFGR_INVCLK_MASK,
        /* data GPIO re-sampled on clock rising edge */
        [2] = STM32_GPIO_ADVCFGR_RET_MASK,
        /* data GPIO re-sampled on clock falling edge */
        [3] = STM32_GPIO_ADVCFGR_RET_MASK | STM32_GPIO_ADVCFGR_INVCLK_MASK,
        /* data GPIO re-sampled on both clock edges */
        [4] = STM32_GPIO_ADVCFGR_RET_MASK | STM32_GPIO_ADVCFGR_DE_MASK,
};

static const struct pinconf_generic_params stm32_gpio_bindings[] = {
        {"st,io-sync", STM32_GPIO_PIN_CONFIG_IO_SYNC, 0,
         stm32_gpio_io_sync, ARRAY_SIZE(stm32_gpio_io_sync)},
};

struct stm32_pinctrl_group {
        const char *name;
        unsigned long config;
        unsigned pin;
};

struct stm32_pin_backup {
        unsigned int alt:4;
        unsigned int mode:2;
        unsigned int bias:2;
        unsigned int speed:2;
        unsigned int drive:1;
        unsigned int value:1;
        unsigned int advcfg:4;
        unsigned int skew_delay:4;
};

struct stm32_gpio_bank {
        void __iomem *base;
        struct reset_control *rstc;
        spinlock_t lock;
        struct gpio_chip gpio_chip;
        struct pinctrl_gpio_range range;
        struct fwnode_handle *fwnode;
        struct irq_domain *domain;
        u32 bank_nr;
        u32 bank_ioport_nr;
        struct stm32_pin_backup pin_backup[STM32_GPIO_PINS_PER_BANK];
        u8 irq_type[STM32_GPIO_PINS_PER_BANK];
        bool secure_control;
        bool io_sync_control;
        bool rif_control;
};

struct stm32_pinctrl {
        struct device *dev;
        struct pinctrl_dev *pctl_dev;
        struct pinctrl_desc pctl_desc;
        struct stm32_pinctrl_group *groups;
        unsigned ngroups;
        const char **grp_names;
        struct stm32_gpio_bank *banks;
        struct clk_bulk_data *clks;
        unsigned nbanks;
        const struct stm32_pinctrl_match_data *match_data;
        struct irq_domain       *domain;
        struct regmap           *regmap;
        struct regmap_field     *irqmux[STM32_GPIO_PINS_PER_BANK];
        struct hwspinlock *hwlock;
        struct stm32_desc_pin *pins;
        u32 npins;
        u32 pkg;
        u16 irqmux_map;
        spinlock_t irqmux_lock;
};

static void stm32_pmx_get_mode(struct stm32_gpio_bank *bank, int pin, u32 *mode, u32 *alt);

static inline int stm32_gpio_pin(int gpio)
{
        return gpio % STM32_GPIO_PINS_PER_BANK;
}

static inline u32 stm32_gpio_get_mode(u32 function)
{
        switch (function) {
        case STM32_PIN_GPIO:
                return 0;
        case STM32_PIN_AF(0) ... STM32_PIN_AF(15):
                return 2;
        case STM32_PIN_ANALOG:
                return 3;
        }

        return 0;
}

static inline u32 stm32_gpio_get_alt(u32 function)
{
        switch (function) {
        case STM32_PIN_GPIO:
                return 0;
        case STM32_PIN_AF(0) ... STM32_PIN_AF(15):
                return function - 1;
        case STM32_PIN_ANALOG:
                return 0;
        }

        return 0;
}

static void stm32_gpio_backup_value(struct stm32_gpio_bank *bank,
                                    u32 offset, u32 value)
{
        bank->pin_backup[offset].value = value;
}

static void stm32_gpio_backup_mode(struct stm32_gpio_bank *bank, u32 offset,
                                   u32 mode, u32 alt)
{
        bank->pin_backup[offset].mode = mode;
        bank->pin_backup[offset].alt = alt;
}

static void stm32_gpio_backup_driving(struct stm32_gpio_bank *bank, u32 offset,
                                      u32 drive)
{
        bank->pin_backup[offset].drive = drive;
}

static void stm32_gpio_backup_speed(struct stm32_gpio_bank *bank, u32 offset,
                                    u32 speed)
{
        bank->pin_backup[offset].speed = speed;
}

static void stm32_gpio_backup_bias(struct stm32_gpio_bank *bank, u32 offset,
                                   u32 bias)
{
        bank->pin_backup[offset].bias = bias;
}

static void stm32_gpio_backup_advcfg(struct stm32_gpio_bank *bank, u32 offset, u32 mask, u32 value)
{
        u32 val;

        val = bank->pin_backup[offset].advcfg;
        val &= ~mask;
        val |= value & mask;
        bank->pin_backup[offset].advcfg = val;
}

static void stm32_gpio_backup_skew_delay(struct stm32_gpio_bank *bank, u32 offset, u32 delay)
{
        bank->pin_backup[offset].skew_delay = delay;
}

/* RIF functions */

static bool stm32_gpio_rif_valid(struct stm32_gpio_bank *bank, unsigned int gpio_nr)
{
        u32 cid;

        cid = readl_relaxed(bank->base + STM32_GPIO_CIDCFGR(gpio_nr));

        if (!(cid & STM32_GPIO_CIDCFGR_CFEN))
                return true;

        if (!(cid & STM32_GPIO_CIDCFGR_SEMEN)) {
                if (FIELD_GET(STM32_GPIO_CIDCFGR_SCID_MASK, cid) == STM32_GPIO_CID1)
                        return true;

                return false;
        }

        if (cid & STM32_GPIO_CIDCFGR_SEMWL_CID1)
                return true;

        return false;
}

static bool stm32_gpio_rif_acquire_semaphore(struct stm32_gpio_bank *bank, unsigned int gpio_nr)
{
        u32 cid, sem;

        cid = readl_relaxed(bank->base + STM32_GPIO_CIDCFGR(gpio_nr));

        if (!(cid & STM32_GPIO_CIDCFGR_CFEN))
                return true;

        if (!(cid & STM32_GPIO_CIDCFGR_SEMEN)) {
                if (FIELD_GET(STM32_GPIO_CIDCFGR_SCID_MASK, cid) == STM32_GPIO_CID1)
                        return true;

                return false;
        }

        if (!(cid & STM32_GPIO_CIDCFGR_SEMWL_CID1))
                return false;

        sem = readl_relaxed(bank->base + STM32_GPIO_SEMCR(gpio_nr));
        if (sem & STM32_GPIO_SEMCR_SEM_MUTEX) {
                if (FIELD_GET(STM32_GPIO_SEMCR_SEMCID_MASK, sem) == STM32_GPIO_CID1)
                        return true;

                return false;
        }

        writel_relaxed(STM32_GPIO_SEMCR_SEM_MUTEX, bank->base + STM32_GPIO_SEMCR(gpio_nr));

        sem = readl_relaxed(bank->base + STM32_GPIO_SEMCR(gpio_nr));
        if (sem & STM32_GPIO_SEMCR_SEM_MUTEX &&
            FIELD_GET(STM32_GPIO_SEMCR_SEMCID_MASK, sem) == STM32_GPIO_CID1)
                return true;

        return false;
}

static void stm32_gpio_rif_release_semaphore(struct stm32_gpio_bank *bank, unsigned int gpio_nr)
{
        u32 cid;

        cid = readl_relaxed(bank->base + STM32_GPIO_CIDCFGR(gpio_nr));

        if (!(cid & STM32_GPIO_CIDCFGR_CFEN))
                return;

        if (cid & STM32_GPIO_CIDCFGR_SEMEN)
                writel_relaxed(0, bank->base + STM32_GPIO_SEMCR(gpio_nr));
}

/* GPIO functions */

static inline void __stm32_gpio_set(struct stm32_gpio_bank *bank,
        unsigned int offset, u32 value)
{
        stm32_gpio_backup_value(bank, offset, value);

        if (!value)
                offset += STM32_GPIO_PINS_PER_BANK;

        writel_relaxed(BIT(offset), bank->base + STM32_GPIO_BSRR);
}

static int stm32_gpio_request(struct gpio_chip *chip, unsigned offset)
{
        struct stm32_gpio_bank *bank = gpiochip_get_data(chip);
        struct stm32_pinctrl *pctl = dev_get_drvdata(bank->gpio_chip.parent);
        struct pinctrl_gpio_range *range;
        int pin = offset + (bank->bank_nr * STM32_GPIO_PINS_PER_BANK);

        range = pinctrl_find_gpio_range_from_pin_nolock(pctl->pctl_dev, pin);
        if (!range) {
                dev_err(pctl->dev, "pin %d not in range.\n", pin);
                return -EINVAL;
        }

        if (bank->rif_control && !stm32_gpio_rif_acquire_semaphore(bank, offset)) {
                dev_err(pctl->dev, "pin %d not available.\n", offset);
                return -EACCES;
        }

        return pinctrl_gpio_request(chip, offset);
}

static void stm32_gpio_free(struct gpio_chip *chip, unsigned int offset)
{
        struct stm32_gpio_bank *bank = gpiochip_get_data(chip);

        pinctrl_gpio_free(chip, offset);

        if (bank->rif_control)
                stm32_gpio_rif_release_semaphore(bank, offset);
}

static int stm32_gpio_get(struct gpio_chip *chip, unsigned offset)
{
        struct stm32_gpio_bank *bank = gpiochip_get_data(chip);

        return !!(readl_relaxed(bank->base + STM32_GPIO_IDR) & BIT(offset));
}

static int stm32_gpio_set(struct gpio_chip *chip, unsigned int offset,
                          int value)
{
        struct stm32_gpio_bank *bank = gpiochip_get_data(chip);

        __stm32_gpio_set(bank, offset, value);

        return 0;
}

static int stm32_gpio_direction_output(struct gpio_chip *chip,
        unsigned offset, int value)
{
        struct stm32_gpio_bank *bank = gpiochip_get_data(chip);

        __stm32_gpio_set(bank, offset, value);

        return pinctrl_gpio_direction_output(chip, offset);
}


static int stm32_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
{
        struct stm32_gpio_bank *bank = gpiochip_get_data(chip);
        struct irq_fwspec fwspec;

        fwspec.fwnode = bank->fwnode;
        fwspec.param_count = 2;
        fwspec.param[0] = offset;
        fwspec.param[1] = IRQ_TYPE_NONE;

        return irq_create_fwspec_mapping(&fwspec);
}

static int stm32_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
{
        struct stm32_gpio_bank *bank = gpiochip_get_data(chip);
        int pin = stm32_gpio_pin(offset);
        int ret;
        u32 mode, alt;

        stm32_pmx_get_mode(bank, pin, &mode, &alt);
        if ((alt == 0) && (mode == 0))
                ret = GPIO_LINE_DIRECTION_IN;
        else if ((alt == 0) && (mode == 1))
                ret = GPIO_LINE_DIRECTION_OUT;
        else
                ret = -EINVAL;

        return ret;
}

static int stm32_gpio_init_valid_mask(struct gpio_chip *chip,
                                      unsigned long *valid_mask,
                                      unsigned int ngpios)
{
        struct stm32_gpio_bank *bank = gpiochip_get_data(chip);
        struct stm32_pinctrl *pctl = dev_get_drvdata(bank->gpio_chip.parent);
        unsigned int i;
        u32 sec;

        /* All gpio are valid per default */
        bitmap_fill(valid_mask, ngpios);

        if (bank->secure_control) {
                /* Tag secured pins as invalid */
                sec = readl_relaxed(bank->base + STM32_GPIO_SECCFGR);

                for (i = 0; i < ngpios; i++) {
                        if (sec & BIT(i)) {
                                clear_bit(i, valid_mask);
                                dev_dbg(pctl->dev, "No access to gpio %d - %d\n", bank->bank_nr, i);
                        }
                }
        }

        if (bank->rif_control) {
                for (i = 0; i < ngpios; i++) {
                        if (!test_bit(i, valid_mask))
                                continue;

                        if (stm32_gpio_rif_valid(bank, i))
                                continue;

                        dev_dbg(pctl->dev, "RIF semaphore ownership conflict, GPIO %u", i);
                        clear_bit(i, valid_mask);
                }
        }

        return 0;
}

static const struct gpio_chip stm32_gpio_template = {
        .request                = stm32_gpio_request,
        .free                   = stm32_gpio_free,
        .get                    = stm32_gpio_get,
        .set                    = stm32_gpio_set,
        .direction_input        = pinctrl_gpio_direction_input,
        .direction_output       = stm32_gpio_direction_output,
        .to_irq                 = stm32_gpio_to_irq,
        .get_direction          = stm32_gpio_get_direction,
        .set_config             = gpiochip_generic_config,
        .init_valid_mask        = stm32_gpio_init_valid_mask,
};

static void stm32_gpio_irq_trigger(struct irq_data *d)
{
        struct stm32_gpio_bank *bank = d->domain->host_data;
        int level;

        /* Do not access the GPIO if this is not LEVEL triggered IRQ. */
        if (!(bank->irq_type[d->hwirq] & IRQ_TYPE_LEVEL_MASK))
                return;

        /* If level interrupt type then retrig */
        level = stm32_gpio_get(&bank->gpio_chip, d->hwirq);
        if ((level == 0 && bank->irq_type[d->hwirq] == IRQ_TYPE_LEVEL_LOW) ||
            (level == 1 && bank->irq_type[d->hwirq] == IRQ_TYPE_LEVEL_HIGH))
                irq_chip_retrigger_hierarchy(d);
}

static void stm32_gpio_irq_eoi(struct irq_data *d)
{
        irq_chip_eoi_parent(d);
        stm32_gpio_irq_trigger(d);
};

static int stm32_gpio_set_type(struct irq_data *d, unsigned int type)
{
        struct stm32_gpio_bank *bank = d->domain->host_data;
        u32 parent_type;

        switch (type) {
        case IRQ_TYPE_EDGE_RISING:
        case IRQ_TYPE_EDGE_FALLING:
        case IRQ_TYPE_EDGE_BOTH:
                parent_type = type;
                break;
        case IRQ_TYPE_LEVEL_HIGH:
                parent_type = IRQ_TYPE_EDGE_RISING;
                break;
        case IRQ_TYPE_LEVEL_LOW:
                parent_type = IRQ_TYPE_EDGE_FALLING;
                break;
        default:
                return -EINVAL;
        }

        bank->irq_type[d->hwirq] = type;

        return irq_chip_set_type_parent(d, parent_type);
};

static int stm32_gpio_irq_request_resources(struct irq_data *irq_data)
{
        struct stm32_gpio_bank *bank = irq_data->domain->host_data;
        struct stm32_pinctrl *pctl = dev_get_drvdata(bank->gpio_chip.parent);
        int ret;

        ret = pinctrl_gpio_direction_input(&bank->gpio_chip, irq_data->hwirq);
        if (ret)
                return ret;

        ret = gpiochip_lock_as_irq(&bank->gpio_chip, irq_data->hwirq);
        if (ret) {
                dev_err(pctl->dev, "unable to lock HW IRQ %lu for IRQ\n",
                        irq_data->hwirq);
                return ret;
        }

        return 0;
}

static void stm32_gpio_irq_release_resources(struct irq_data *irq_data)
{
        struct stm32_gpio_bank *bank = irq_data->domain->host_data;

        gpiochip_unlock_as_irq(&bank->gpio_chip, irq_data->hwirq);
}

static void stm32_gpio_irq_unmask(struct irq_data *d)
{
        irq_chip_unmask_parent(d);
        stm32_gpio_irq_trigger(d);
}

static struct irq_chip stm32_gpio_irq_chip = {
        .name           = "stm32gpio",
        .irq_eoi        = stm32_gpio_irq_eoi,
        .irq_ack        = irq_chip_ack_parent,
        .irq_mask       = irq_chip_mask_parent,
        .irq_unmask     = stm32_gpio_irq_unmask,
        .irq_set_type   = stm32_gpio_set_type,
        .irq_set_wake   = irq_chip_set_wake_parent,
        .irq_request_resources = stm32_gpio_irq_request_resources,
        .irq_release_resources = stm32_gpio_irq_release_resources,
        .irq_set_affinity = IS_ENABLED(CONFIG_SMP) ? irq_chip_set_affinity_parent : NULL,
};

static int stm32_gpio_domain_translate(struct irq_domain *d,
                                       struct irq_fwspec *fwspec,
                                       unsigned long *hwirq,
                                       unsigned int *type)
{
        if ((fwspec->param_count != 2) ||
            (fwspec->param[0] >= STM32_GPIO_IRQ_LINE))
                return -EINVAL;

        *hwirq = fwspec->param[0];
        *type = fwspec->param[1];
        return 0;
}

static int stm32_gpio_domain_activate(struct irq_domain *d,
                                      struct irq_data *irq_data, bool reserve)
{
        struct stm32_gpio_bank *bank = d->host_data;
        struct stm32_pinctrl *pctl = dev_get_drvdata(bank->gpio_chip.parent);
        int ret = 0;

        if (pctl->hwlock) {
                ret = hwspin_lock_timeout_in_atomic(pctl->hwlock,
                                                    HWSPNLCK_TIMEOUT);
                if (ret) {
                        dev_err(pctl->dev, "Can't get hwspinlock\n");
                        return ret;
                }
        }

        regmap_field_write(pctl->irqmux[irq_data->hwirq], bank->bank_ioport_nr);

        if (pctl->hwlock)
                hwspin_unlock_in_atomic(pctl->hwlock);

        return ret;
}

static int stm32_gpio_domain_alloc(struct irq_domain *d,
                                   unsigned int virq,
                                   unsigned int nr_irqs, void *data)
{
        struct stm32_gpio_bank *bank = d->host_data;
        struct irq_fwspec *fwspec = data;
        struct irq_fwspec parent_fwspec;
        struct stm32_pinctrl *pctl = dev_get_drvdata(bank->gpio_chip.parent);
        irq_hw_number_t hwirq = fwspec->param[0];
        unsigned long flags;
        int ret = 0;

        /*
         * Check first that the IRQ MUX of that line is free.
         * gpio irq mux is shared between several banks, protect with a lock
         */
        spin_lock_irqsave(&pctl->irqmux_lock, flags);

        if (pctl->irqmux_map & BIT(hwirq)) {
                dev_err(pctl->dev, "irq line %ld already requested.\n", hwirq);
                ret = -EBUSY;
        } else {
                pctl->irqmux_map |= BIT(hwirq);
        }

        spin_unlock_irqrestore(&pctl->irqmux_lock, flags);
        if (ret)
                return ret;

        parent_fwspec.fwnode = d->parent->fwnode;
        parent_fwspec.param_count = 2;
        parent_fwspec.param[0] = fwspec->param[0];
        parent_fwspec.param[1] = fwspec->param[1];

        irq_domain_set_hwirq_and_chip(d, virq, hwirq, &stm32_gpio_irq_chip,
                                      bank);

        return irq_domain_alloc_irqs_parent(d, virq, nr_irqs, &parent_fwspec);
}

static void stm32_gpio_domain_free(struct irq_domain *d, unsigned int virq,
                                   unsigned int nr_irqs)
{
        struct stm32_gpio_bank *bank = d->host_data;
        struct stm32_pinctrl *pctl = dev_get_drvdata(bank->gpio_chip.parent);
        struct irq_data *irq_data = irq_domain_get_irq_data(d, virq);
        unsigned long flags, hwirq = irq_data->hwirq;

        irq_domain_free_irqs_common(d, virq, nr_irqs);

        spin_lock_irqsave(&pctl->irqmux_lock, flags);
        pctl->irqmux_map &= ~BIT(hwirq);
        spin_unlock_irqrestore(&pctl->irqmux_lock, flags);
}

static const struct irq_domain_ops stm32_gpio_domain_ops = {
        .translate      = stm32_gpio_domain_translate,
        .alloc          = stm32_gpio_domain_alloc,
        .free           = stm32_gpio_domain_free,
        .activate       = stm32_gpio_domain_activate,
};

/* Pinctrl functions */
static struct stm32_pinctrl_group *
stm32_pctrl_find_group_by_pin(struct stm32_pinctrl *pctl, u32 pin)
{
        int i;

        for (i = 0; i < pctl->ngroups; i++) {
                struct stm32_pinctrl_group *grp = pctl->groups + i;

                if (grp->pin == pin)
                        return grp;
        }

        return NULL;
}

static bool stm32_pctrl_is_function_valid(struct stm32_pinctrl *pctl,
                u32 pin_num, u32 fnum)
{
        int i, k;

        for (i = 0; i < pctl->npins; i++) {
                const struct stm32_desc_pin *pin = pctl->pins + i;
                const struct stm32_desc_function *func = pin->functions;

                if (pin->pin.number != pin_num)
                        continue;

                if (fnum == STM32_PIN_RSVD)
                        return true;

                for (k = 0; k < STM32_CONFIG_NUM; k++) {
                        if (func->num == fnum)
                                return true;
                        func++;
                }

                break;
        }

        dev_err(pctl->dev, "invalid function %d on pin %d .\n", fnum, pin_num);

        return false;
}

static int stm32_pctrl_dt_node_to_map_func(struct stm32_pinctrl *pctl,
                u32 pin, u32 fnum, struct stm32_pinctrl_group *grp,
                struct pinctrl_map **map, unsigned *reserved_maps,
                unsigned *num_maps)
{
        if (*num_maps == *reserved_maps)
                return -ENOSPC;

        (*map)[*num_maps].type = PIN_MAP_TYPE_MUX_GROUP;
        (*map)[*num_maps].data.mux.group = grp->name;

        if (!stm32_pctrl_is_function_valid(pctl, pin, fnum))
                return -EINVAL;

        (*map)[*num_maps].data.mux.function = stm32_gpio_functions[fnum];
        (*num_maps)++;

        return 0;
}

static int stm32_pctrl_dt_subnode_to_map(struct pinctrl_dev *pctldev,
                                      struct device_node *node,
                                      struct pinctrl_map **map,
                                      unsigned *reserved_maps,
                                      unsigned *num_maps)
{
        struct stm32_pinctrl *pctl;
        struct stm32_pinctrl_group *grp;
        struct property *pins;
        u32 pinfunc, pin, func;
        unsigned long *configs;
        unsigned int num_configs;
        bool has_config = 0;
        unsigned reserve = 0;
        int num_pins, num_funcs, maps_per_pin, i, err = 0;

        pctl = pinctrl_dev_get_drvdata(pctldev);

        pins = of_find_property(node, "pinmux", NULL);
        if (!pins) {
                dev_err(pctl->dev, "missing pins property in node %pOFn .\n",
                                node);
                return -EINVAL;
        }

        err = pinconf_generic_parse_dt_config(node, pctldev, &configs,
                &num_configs);
        if (err)
                return err;

        if (num_configs)
                has_config = 1;

        num_pins = pins->length / sizeof(u32);
        num_funcs = num_pins;
        maps_per_pin = 0;
        if (num_funcs)
                maps_per_pin++;
        if (has_config && num_pins >= 1)
                maps_per_pin++;

        if (!num_pins || !maps_per_pin) {
                err = -EINVAL;
                goto exit;
        }

        reserve = num_pins * maps_per_pin;

        err = pinctrl_utils_reserve_map(pctldev, map,
                        reserved_maps, num_maps, reserve);
        if (err)
                goto exit;

        for (i = 0; i < num_pins; i++) {
                err = of_property_read_u32_index(node, "pinmux",
                                i, &pinfunc);
                if (err)
                        goto exit;

                pin = STM32_GET_PIN_NO(pinfunc);
                func = STM32_GET_PIN_FUNC(pinfunc);

                if (!stm32_pctrl_is_function_valid(pctl, pin, func)) {
                        err = -EINVAL;
                        goto exit;
                }

                grp = stm32_pctrl_find_group_by_pin(pctl, pin);
                if (!grp) {
                        dev_err(pctl->dev, "unable to match pin %d to group\n",
                                        pin);
                        err = -EINVAL;
                        goto exit;
                }

                err = stm32_pctrl_dt_node_to_map_func(pctl, pin, func, grp, map,
                                reserved_maps, num_maps);
                if (err)
                        goto exit;

                if (has_config) {
                        err = pinctrl_utils_add_map_configs(pctldev, map,
                                        reserved_maps, num_maps, grp->name,
                                        configs, num_configs,
                                        PIN_MAP_TYPE_CONFIGS_GROUP);
                        if (err)
                                goto exit;
                }
        }

exit:
        kfree(configs);
        return err;
}

static int stm32_pctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
                                 struct device_node *np_config,
                                 struct pinctrl_map **map, unsigned *num_maps)
{
        unsigned reserved_maps;
        int ret;

        *map = NULL;
        *num_maps = 0;
        reserved_maps = 0;

        for_each_child_of_node_scoped(np_config, np) {
                ret = stm32_pctrl_dt_subnode_to_map(pctldev, np, map,
                                &reserved_maps, num_maps);
                if (ret < 0) {
                        pinctrl_utils_free_map(pctldev, *map, *num_maps);
                        return ret;
                }
        }

        return 0;
}

static int stm32_pctrl_get_groups_count(struct pinctrl_dev *pctldev)
{
        struct stm32_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);

        return pctl->ngroups;
}

static const char *stm32_pctrl_get_group_name(struct pinctrl_dev *pctldev,
                                              unsigned group)
{
        struct stm32_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);

        return pctl->groups[group].name;
}

static int stm32_pctrl_get_group_pins(struct pinctrl_dev *pctldev,
                                      unsigned group,
                                      const unsigned **pins,
                                      unsigned *num_pins)
{
        struct stm32_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);

        *pins = (unsigned *)&pctl->groups[group].pin;
        *num_pins = 1;

        return 0;
}

static const struct pinctrl_ops stm32_pctrl_ops = {
        .dt_node_to_map         = stm32_pctrl_dt_node_to_map,
        .dt_free_map            = pinctrl_utils_free_map,
        .get_groups_count       = stm32_pctrl_get_groups_count,
        .get_group_name         = stm32_pctrl_get_group_name,
        .get_group_pins         = stm32_pctrl_get_group_pins,
};


/* Pinmux functions */

static int stm32_pmx_get_funcs_cnt(struct pinctrl_dev *pctldev)
{
        return ARRAY_SIZE(stm32_gpio_functions);
}

static const char *stm32_pmx_get_func_name(struct pinctrl_dev *pctldev,
                                           unsigned selector)
{
        return stm32_gpio_functions[selector];
}

static int stm32_pmx_get_func_groups(struct pinctrl_dev *pctldev,
                                     unsigned function,
                                     const char * const **groups,
                                     unsigned * const num_groups)
{
        struct stm32_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);

        *groups = pctl->grp_names;
        *num_groups = pctl->ngroups;

        return 0;
}

static int stm32_pmx_set_mode(struct stm32_gpio_bank *bank,
                              int pin, u32 mode, u32 alt)
{
        struct stm32_pinctrl *pctl = dev_get_drvdata(bank->gpio_chip.parent);
        u32 val;
        int alt_shift = (pin % 8) * 4;
        int alt_offset = STM32_GPIO_AFRL + (pin / 8) * 4;
        unsigned long flags;
        int err = 0;

        spin_lock_irqsave(&bank->lock, flags);

        if (pctl->hwlock) {
                err = hwspin_lock_timeout_in_atomic(pctl->hwlock,
                                                    HWSPNLCK_TIMEOUT);
                if (err) {
                        dev_err(pctl->dev, "Can't get hwspinlock\n");
                        goto unlock;
                }
        }

        val = readl_relaxed(bank->base + alt_offset);
        val &= ~GENMASK(alt_shift + 3, alt_shift);
        val |= (alt << alt_shift);
        writel_relaxed(val, bank->base + alt_offset);

        val = readl_relaxed(bank->base + STM32_GPIO_MODER);
        val &= ~GENMASK(pin * 2 + 1, pin * 2);
        val |= mode << (pin * 2);
        writel_relaxed(val, bank->base + STM32_GPIO_MODER);

        if (pctl->hwlock)
                hwspin_unlock_in_atomic(pctl->hwlock);

        stm32_gpio_backup_mode(bank, pin, mode, alt);

unlock:
        spin_unlock_irqrestore(&bank->lock, flags);

        return err;
}

static void stm32_pmx_get_mode(struct stm32_gpio_bank *bank, int pin, u32 *mode, u32 *alt)
{
        u32 val;
        int alt_shift = (pin % 8) * 4;
        int alt_offset = STM32_GPIO_AFRL + (pin / 8) * 4;

        val = readl_relaxed(bank->base + alt_offset);
        val &= GENMASK(alt_shift + 3, alt_shift);
        *alt = val >> alt_shift;

        val = readl_relaxed(bank->base + STM32_GPIO_MODER);
        val &= GENMASK(pin * 2 + 1, pin * 2);
        *mode = val >> (pin * 2);
}

static int stm32_pmx_set_mux(struct pinctrl_dev *pctldev,
                            unsigned function,
                            unsigned group)
{
        bool ret;
        struct stm32_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
        struct stm32_pinctrl_group *g = pctl->groups + group;
        struct pinctrl_gpio_range *range;
        struct stm32_gpio_bank *bank;
        u32 mode, alt;
        int pin;

        ret = stm32_pctrl_is_function_valid(pctl, g->pin, function);
        if (!ret)
                return -EINVAL;

        range = pinctrl_find_gpio_range_from_pin(pctldev, g->pin);
        if (!range) {
                dev_err(pctl->dev, "No gpio range defined.\n");
                return -EINVAL;
        }

        if (function == STM32_PIN_RSVD) {
                dev_dbg(pctl->dev, "Reserved pins, skipping HW update.\n");
                return 0;
        }

        bank = gpiochip_get_data(range->gc);
        pin = stm32_gpio_pin(g->pin);

        mode = stm32_gpio_get_mode(function);
        alt = stm32_gpio_get_alt(function);

        return stm32_pmx_set_mode(bank, pin, mode, alt);
}

static int stm32_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
                        struct pinctrl_gpio_range *range, unsigned gpio,
                        bool input)
{
        struct stm32_gpio_bank *bank = gpiochip_get_data(range->gc);
        int pin = stm32_gpio_pin(gpio);

        return stm32_pmx_set_mode(bank, pin, !input, 0);
}

static int stm32_pmx_request(struct pinctrl_dev *pctldev, unsigned int gpio)
{
        struct stm32_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
        unsigned int offset = stm32_gpio_pin(gpio);
        struct pinctrl_gpio_range *range;
        struct stm32_gpio_bank *bank;

        range = pinctrl_find_gpio_range_from_pin_nolock(pctldev, gpio);
        if (!range) {
                dev_err(pctl->dev, "No gpio range defined.\n");
                return -EINVAL;
        }

        if (!gpiochip_line_is_valid(range->gc, offset)) {
                dev_warn(pctl->dev, "Can't access gpio %d\n", gpio);
                return -EACCES;
        }

        bank = gpiochip_get_data(range->gc);
        if (!bank)
                return -ENODEV;

        if (bank->rif_control && !stm32_gpio_rif_acquire_semaphore(bank, offset)) {
                dev_err(pctl->dev, "pin %d not available.\n", offset);
                return -EACCES;
        }

        return 0;
}

static const struct pinmux_ops stm32_pmx_ops = {
        .get_functions_count    = stm32_pmx_get_funcs_cnt,
        .get_function_name      = stm32_pmx_get_func_name,
        .get_function_groups    = stm32_pmx_get_func_groups,
        .set_mux                = stm32_pmx_set_mux,
        .gpio_set_direction     = stm32_pmx_gpio_set_direction,
        .request                = stm32_pmx_request,
        .strict                 = true,
};

/* Pinconf functions */

static int stm32_pconf_set_driving(struct stm32_gpio_bank *bank,
                                   unsigned offset, u32 drive)
{
        struct stm32_pinctrl *pctl = dev_get_drvdata(bank->gpio_chip.parent);
        unsigned long flags;
        u32 val;
        int err = 0;

        spin_lock_irqsave(&bank->lock, flags);

        if (pctl->hwlock) {
                err = hwspin_lock_timeout_in_atomic(pctl->hwlock,
                                                    HWSPNLCK_TIMEOUT);
                if (err) {
                        dev_err(pctl->dev, "Can't get hwspinlock\n");
                        goto unlock;
                }
        }

        val = readl_relaxed(bank->base + STM32_GPIO_TYPER);
        val &= ~BIT(offset);
        val |= drive << offset;
        writel_relaxed(val, bank->base + STM32_GPIO_TYPER);

        if (pctl->hwlock)
                hwspin_unlock_in_atomic(pctl->hwlock);

        stm32_gpio_backup_driving(bank, offset, drive);

unlock:
        spin_unlock_irqrestore(&bank->lock, flags);

        return err;
}

static u32 stm32_pconf_get_driving(struct stm32_gpio_bank *bank,
        unsigned int offset)
{
        u32 val;

        val = readl_relaxed(bank->base + STM32_GPIO_TYPER);
        val &= BIT(offset);

        return (val >> offset);
}

static int stm32_pconf_set_speed(struct stm32_gpio_bank *bank,
                                 unsigned offset, u32 speed)
{
        struct stm32_pinctrl *pctl = dev_get_drvdata(bank->gpio_chip.parent);
        unsigned long flags;
        u32 val;
        int err = 0;

        spin_lock_irqsave(&bank->lock, flags);

        if (pctl->hwlock) {
                err = hwspin_lock_timeout_in_atomic(pctl->hwlock,
                                                    HWSPNLCK_TIMEOUT);
                if (err) {
                        dev_err(pctl->dev, "Can't get hwspinlock\n");
                        goto unlock;
                }
        }

        val = readl_relaxed(bank->base + STM32_GPIO_SPEEDR);
        val &= ~GENMASK(offset * 2 + 1, offset * 2);
        val |= speed << (offset * 2);
        writel_relaxed(val, bank->base + STM32_GPIO_SPEEDR);

        if (pctl->hwlock)
                hwspin_unlock_in_atomic(pctl->hwlock);

        stm32_gpio_backup_speed(bank, offset, speed);

unlock:
        spin_unlock_irqrestore(&bank->lock, flags);

        return err;
}

static u32 stm32_pconf_get_speed(struct stm32_gpio_bank *bank,
        unsigned int offset)
{
        u32 val;

        val = readl_relaxed(bank->base + STM32_GPIO_SPEEDR);
        val &= GENMASK(offset * 2 + 1, offset * 2);

        return (val >> (offset * 2));
}

static int stm32_pconf_set_bias(struct stm32_gpio_bank *bank,
                                unsigned offset, u32 bias)
{
        struct stm32_pinctrl *pctl = dev_get_drvdata(bank->gpio_chip.parent);
        unsigned long flags;
        u32 val;
        int err = 0;

        spin_lock_irqsave(&bank->lock, flags);

        if (pctl->hwlock) {
                err = hwspin_lock_timeout_in_atomic(pctl->hwlock,
                                                    HWSPNLCK_TIMEOUT);
                if (err) {
                        dev_err(pctl->dev, "Can't get hwspinlock\n");
                        goto unlock;
                }
        }

        val = readl_relaxed(bank->base + STM32_GPIO_PUPDR);
        val &= ~GENMASK(offset * 2 + 1, offset * 2);
        val |= bias << (offset * 2);
        writel_relaxed(val, bank->base + STM32_GPIO_PUPDR);

        if (pctl->hwlock)
                hwspin_unlock_in_atomic(pctl->hwlock);

        stm32_gpio_backup_bias(bank, offset, bias);

unlock:
        spin_unlock_irqrestore(&bank->lock, flags);

        return err;
}

static u32 stm32_pconf_get_bias(struct stm32_gpio_bank *bank,
        unsigned int offset)
{
        u32 val;

        val = readl_relaxed(bank->base + STM32_GPIO_PUPDR);
        val &= GENMASK(offset * 2 + 1, offset * 2);

        return (val >> (offset * 2));
}

static void
stm32_pconf_set_advcfgr_nolock(struct stm32_gpio_bank *bank, int offset, u32 mask, u32 value)
{
        int advcfgr_offset = STM32_GPIO_ADVCFGRL + (offset / 8) * 4;
        int advcfgr_shift = (offset % 8) * 4;
        u32 val;

        val = readl_relaxed(bank->base + advcfgr_offset);
        val &= ~(mask << advcfgr_shift);
        val |= (value & mask) << advcfgr_shift;
        writel_relaxed(val, bank->base + advcfgr_offset);

        stm32_gpio_backup_advcfg(bank, offset, mask, value);
}

static int stm32_pconf_set_advcfgr(struct stm32_gpio_bank *bank, int offset, u32 mask, u32 value)
{
        struct stm32_pinctrl *pctl = dev_get_drvdata(bank->gpio_chip.parent);
        unsigned long flags;
        int err = 0;

        if (!bank->io_sync_control)
                return -ENOTSUPP;

        spin_lock_irqsave(&bank->lock, flags);

        if (pctl->hwlock) {
                err = hwspin_lock_timeout_in_atomic(pctl->hwlock, HWSPNLCK_TIMEOUT);
                if (err) {
                        dev_err(pctl->dev, "Can't get hwspinlock\n");
                        goto unlock;
                }
        }

        stm32_pconf_set_advcfgr_nolock(bank, offset, mask, value);

        if (pctl->hwlock)
                hwspin_unlock_in_atomic(pctl->hwlock);

unlock:
        spin_unlock_irqrestore(&bank->lock, flags);

        return err;
}

static u32 stm32_pconf_get_advcfgr(struct stm32_gpio_bank *bank, int offset, u32 mask)
{
        int advcfgr_offset = STM32_GPIO_ADVCFGRL + (offset / 8) * 4;
        int advcfgr_shift = (offset % 8) * 4;
        u32 val;

        if (!bank->io_sync_control)
                return 0;

        val = readl_relaxed(bank->base + advcfgr_offset);
        val >>= advcfgr_shift;

        return val & mask;
}

static int stm32_pconf_set_io_sync(struct stm32_gpio_bank *bank, int offset, u32 io_sync)
{
        if (io_sync >= ARRAY_SIZE(io_sync_2_advcfgr))
                return -EINVAL;

        return stm32_pconf_set_advcfgr(bank, offset, STM32_GPIO_ADVCFGR_IO_SYNC_MASK,
                io_sync_2_advcfgr[io_sync]);
}

static const char *stm32_pconf_get_io_sync_str(struct stm32_gpio_bank *bank, int offset)
{
        u32 io_sync = stm32_pconf_get_advcfgr(bank, offset, STM32_GPIO_ADVCFGR_IO_SYNC_MASK);

        if (io_sync & STM32_GPIO_ADVCFGR_RET_MASK) {
                if (io_sync & STM32_GPIO_ADVCFGR_DE_MASK)
                        return "data GPIO re-sampled on both clock edges";

                if (io_sync & STM32_GPIO_ADVCFGR_INVCLK_MASK)
                        return "data GPIO re-sampled on clock falling edge";

                return "data GPIO re-sampled on clock rising edge";
        }

        if (io_sync & STM32_GPIO_ADVCFGR_INVCLK_MASK)
                return "clock GPIO inverted";

        return NULL;
}

static int
stm32_pconf_set_skew_delay(struct stm32_gpio_bank *bank, int offset, u32 delay, bool is_dir_input)
{
        struct stm32_pinctrl *pctl = dev_get_drvdata(bank->gpio_chip.parent);
        int delay_offset = STM32_GPIO_DELAYRL + (offset / 8) * 4;
        int delay_shift = (offset % 8) * 4;
        unsigned long flags;
        int err = 0;
        u32 val;

        if (!bank->io_sync_control)
                return -ENOTSUPP;

        spin_lock_irqsave(&bank->lock, flags);

        if (pctl->hwlock) {
                err = hwspin_lock_timeout_in_atomic(pctl->hwlock, HWSPNLCK_TIMEOUT);
                if (err) {
                        dev_err(pctl->dev, "Can't get hwspinlock\n");
                        goto unlock;
                }
        }

        val = readl_relaxed(bank->base + delay_offset);
        val &= ~GENMASK(delay_shift + 3, delay_shift);
        val |= (delay << delay_shift);
        writel_relaxed(val, bank->base + delay_offset);

        stm32_gpio_backup_skew_delay(bank, offset, delay);

        stm32_pconf_set_advcfgr_nolock(bank, offset, STM32_GPIO_ADVCFGR_DLYPATH_MASK,
                                       is_dir_input ? STM32_GPIO_ADVCFGR_DLYPATH_MASK : 0);

        if (pctl->hwlock)
                hwspin_unlock_in_atomic(pctl->hwlock);

unlock:
        spin_unlock_irqrestore(&bank->lock, flags);

        return err;
}

static u32 stm32_pconf_get_skew_delay_val(struct stm32_gpio_bank *bank, int offset)
{
        int delay_offset = STM32_GPIO_DELAYRL + (offset / 8) * 4;
        int delay_shift = (offset % 8) * 4;
        u32 val;

        val = readl_relaxed(bank->base + delay_offset);
        val &= GENMASK(delay_shift + 3, delay_shift);

        return val >> delay_shift;
}

static const char *stm32_pconf_get_skew_dir_str(struct stm32_gpio_bank *bank, int offset)
{
        return stm32_pconf_get_advcfgr(bank, offset, STM32_GPIO_ADVCFGR_DLYPATH_MASK) ?
                "input" : "output";
}

static bool stm32_pconf_get(struct stm32_gpio_bank *bank,
        unsigned int offset, bool dir)
{
        bool val;

        if (dir)
                val = !!(readl_relaxed(bank->base + STM32_GPIO_IDR) &
                         BIT(offset));
        else
                val = !!(readl_relaxed(bank->base + STM32_GPIO_ODR) &
                         BIT(offset));

        return val;
}

static int stm32_pconf_parse_conf(struct pinctrl_dev *pctldev,
                unsigned int pin, unsigned long config)
{
        struct stm32_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
        unsigned int param = pinconf_to_config_param(config);
        u32 arg = pinconf_to_config_argument(config);
        struct pinctrl_gpio_range *range;
        struct stm32_gpio_bank *bank;
        int offset, ret = 0;

        range = pinctrl_find_gpio_range_from_pin_nolock(pctldev, pin);
        if (!range) {
                dev_err(pctl->dev, "No gpio range defined.\n");
                return -EINVAL;
        }

        bank = gpiochip_get_data(range->gc);
        offset = stm32_gpio_pin(pin);

        if (!gpiochip_line_is_valid(range->gc, offset)) {
                dev_warn(pctl->dev, "Can't access gpio %d\n", pin);
                return -EACCES;
        }

        if (bank->rif_control && !stm32_gpio_rif_acquire_semaphore(bank, offset)) {
                dev_err(pctl->dev, "pin %d not available.\n", offset);
                return -EACCES;
        }

        switch (param) {
        case PIN_CONFIG_DRIVE_PUSH_PULL:
                ret = stm32_pconf_set_driving(bank, offset, 0);
                break;
        case PIN_CONFIG_DRIVE_OPEN_DRAIN:
                ret = stm32_pconf_set_driving(bank, offset, 1);
                break;
        case PIN_CONFIG_SLEW_RATE:
                ret = stm32_pconf_set_speed(bank, offset, arg);
                break;
        case PIN_CONFIG_BIAS_DISABLE:
                ret = stm32_pconf_set_bias(bank, offset, 0);
                break;
        case PIN_CONFIG_BIAS_PULL_UP:
                ret = stm32_pconf_set_bias(bank, offset, 1);
                break;
        case PIN_CONFIG_BIAS_PULL_DOWN:
                ret = stm32_pconf_set_bias(bank, offset, 2);
                break;
        case PIN_CONFIG_LEVEL:
                __stm32_gpio_set(bank, offset, arg);
                ret = stm32_pmx_gpio_set_direction(pctldev, range, pin, false);
                break;
        case PIN_CONFIG_SKEW_DELAY_INPUT_PS:
                arg /= STM32_GPIO_DELAYRL_PS;
                ret = stm32_pconf_set_skew_delay(bank, offset, arg, true);
                break;
        case PIN_CONFIG_SKEW_DELAY_OUTPUT_PS:
                arg /= STM32_GPIO_DELAYRL_PS;
                ret = stm32_pconf_set_skew_delay(bank, offset, arg, false);
                break;
        case STM32_GPIO_PIN_CONFIG_IO_SYNC:
                ret = stm32_pconf_set_io_sync(bank, offset, arg);
                break;
        default:
                ret = -ENOTSUPP;
        }

        return ret;
}

static int stm32_pconf_group_get(struct pinctrl_dev *pctldev,
                                 unsigned group,
                                 unsigned long *config)
{
        struct stm32_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);

        *config = pctl->groups[group].config;

        return 0;
}

static int stm32_pconf_group_set(struct pinctrl_dev *pctldev, unsigned group,
                                 unsigned long *configs, unsigned num_configs)
{
        struct stm32_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
        struct stm32_pinctrl_group *g = &pctl->groups[group];
        int i, ret;

        for (i = 0; i < num_configs; i++) {
                mutex_lock(&pctldev->mutex);
                ret = stm32_pconf_parse_conf(pctldev, g->pin, configs[i]);
                mutex_unlock(&pctldev->mutex);
                if (ret < 0)
                        return ret;

                g->config = configs[i];
        }

        return 0;
}

static int stm32_pconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
                           unsigned long *configs, unsigned int num_configs)
{
        int i, ret;

        for (i = 0; i < num_configs; i++) {
                ret = stm32_pconf_parse_conf(pctldev, pin, configs[i]);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

static struct stm32_desc_pin *
stm32_pconf_get_pin_desc_by_pin_number(struct stm32_pinctrl *pctl,
                                       unsigned int pin_number)
{
        struct stm32_desc_pin *pins = pctl->pins;
        int i;

        for (i = 0; i < pctl->npins; i++) {
                if (pins->pin.number == pin_number)
                        return pins;
                pins++;
        }
        return NULL;
}

static void stm32_pconf_dbg_show(struct pinctrl_dev *pctldev,
                                 struct seq_file *s,
                                 unsigned int pin)
{
        struct stm32_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
        const struct stm32_desc_pin *pin_desc;
        struct pinctrl_gpio_range *range;
        struct stm32_gpio_bank *bank;
        int offset;
        u32 mode, alt, drive, speed, bias;
        static const char * const modes[] = {
                        "input", "output", "alternate", "analog" };
        static const char * const speeds[] = {
                        "low", "medium", "high", "very high" };
        static const char * const biasing[] = {
                        "floating", "pull up", "pull down", "" };
        bool val;

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

        bank = gpiochip_get_data(range->gc);
        offset = stm32_gpio_pin(pin);

        if (!gpiochip_line_is_valid(range->gc, offset)) {
                seq_puts(s, "NO ACCESS");
                return;
        }

        stm32_pmx_get_mode(bank, offset, &mode, &alt);
        bias = stm32_pconf_get_bias(bank, offset);

        seq_printf(s, "%s ", modes[mode]);

        switch (mode) {
        /* input */
        case 0:
                val = stm32_pconf_get(bank, offset, true);
                seq_printf(s, "- %s - %s",
                           str_high_low(val),
                           biasing[bias]);
                break;

        /* output */
        case 1:
                drive = stm32_pconf_get_driving(bank, offset);
                speed = stm32_pconf_get_speed(bank, offset);
                val = stm32_pconf_get(bank, offset, false);
                seq_printf(s, "- %s - %s - %s - %s %s",
                           str_high_low(val),
                           drive ? "open drain" : "push pull",
                           biasing[bias],
                           speeds[speed], "speed");
                break;

        /* alternate */
        case 2:
                drive = stm32_pconf_get_driving(bank, offset);
                speed = stm32_pconf_get_speed(bank, offset);
                pin_desc = stm32_pconf_get_pin_desc_by_pin_number(pctl, pin);
                if (!pin_desc)
                        return;

                seq_printf(s, "%d (%s) - %s - %s - %s %s", alt,
                           pin_desc->functions[alt + 1].name,
                           drive ? "open drain" : "push pull",
                           biasing[bias],
                           speeds[speed], "speed");
                break;

        /* analog */
        case 3:
                break;
        }

        if (bank->io_sync_control) {
                const char *io_sync_str, *skew_dir_str;
                u32 skew_delay;

                io_sync_str = stm32_pconf_get_io_sync_str(bank, offset);
                skew_dir_str = stm32_pconf_get_skew_dir_str(bank, offset);
                skew_delay = stm32_pconf_get_skew_delay_val(bank, offset);

                if (io_sync_str)
                        seq_printf(s, " - IO-sync: %s", io_sync_str);

                if (skew_delay)
                        seq_printf(s, " - Skew-delay: %u (%u ps) %s", skew_delay,
                                   skew_delay * STM32_GPIO_DELAYRL_PS, skew_dir_str);
        }
}

static const struct pinconf_ops stm32_pconf_ops = {
        .pin_config_group_get   = stm32_pconf_group_get,
        .pin_config_group_set   = stm32_pconf_group_set,
        .pin_config_set         = stm32_pconf_set,
        .pin_config_dbg_show    = stm32_pconf_dbg_show,
};

static struct stm32_desc_pin *stm32_pctrl_get_desc_pin_from_gpio(struct stm32_pinctrl *pctl,
                                                                 struct stm32_gpio_bank *bank,
                                                                 unsigned int offset)
{
        unsigned int stm32_pin_nb = bank->bank_nr * STM32_GPIO_PINS_PER_BANK + offset;
        struct stm32_desc_pin *pin_desc;
        int i;

        /* With few exceptions (e.g. bank 'Z'), pin number matches with pin index in array */
        if (stm32_pin_nb < pctl->npins) {
                pin_desc = pctl->pins + stm32_pin_nb;
                if (pin_desc->pin.number == stm32_pin_nb)
                        return pin_desc;
        }

        /* Otherwise, loop all array to find the pin with the right number */
        for (i = 0; i < pctl->npins; i++) {
                pin_desc = pctl->pins + i;
                if (pin_desc->pin.number == stm32_pin_nb)
                        return pin_desc;
        }
        return NULL;
}

static int stm32_gpiolib_register_bank(struct stm32_pinctrl *pctl, struct fwnode_handle *fwnode)
{
        struct stm32_gpio_bank *bank = &pctl->banks[pctl->nbanks];
        int bank_ioport_nr;
        struct pinctrl_gpio_range *range = &bank->range;
        struct fwnode_reference_args args;
        struct device *dev = pctl->dev;
        struct resource res;
        int npins = STM32_GPIO_PINS_PER_BANK;
        int bank_nr, err, i = 0;
        struct stm32_desc_pin *stm32_pin;
        char **names;

        if (!IS_ERR(bank->rstc))
                reset_control_deassert(bank->rstc);

        if (of_address_to_resource(to_of_node(fwnode), 0, &res))
                return -ENODEV;

        bank->base = devm_ioremap_resource(dev, &res);
        if (IS_ERR(bank->base))
                return PTR_ERR(bank->base);

        bank->gpio_chip = stm32_gpio_template;

        fwnode_property_read_string(fwnode, "st,bank-name", &bank->gpio_chip.label);

        if (!fwnode_property_get_reference_args(fwnode, "gpio-ranges", NULL, 3, i, &args)) {
                bank_nr = args.args[1] / STM32_GPIO_PINS_PER_BANK;
                bank->gpio_chip.base = args.args[1];

                /* get the last defined gpio line (offset + nb of pins) */
                npins = args.args[0] + args.args[2];
                while (!fwnode_property_get_reference_args(fwnode, "gpio-ranges", NULL, 3, ++i, &args))
                        npins = max(npins, (int)(args.args[0] + args.args[2]));
        } else {
                bank_nr = pctl->nbanks;
                bank->gpio_chip.base = bank_nr * STM32_GPIO_PINS_PER_BANK;
                range->name = bank->gpio_chip.label;
                range->id = bank_nr;
                range->pin_base = range->id * STM32_GPIO_PINS_PER_BANK;
                range->base = range->id * STM32_GPIO_PINS_PER_BANK;
                range->npins = npins;
                range->gc = &bank->gpio_chip;
                pinctrl_add_gpio_range(pctl->pctl_dev,
                                       &pctl->banks[bank_nr].range);
        }

        if (fwnode_property_read_u32(fwnode, "st,bank-ioport", &bank_ioport_nr))
                bank_ioport_nr = bank_nr;

        bank->gpio_chip.base = -1;

        bank->gpio_chip.ngpio = npins;
        bank->gpio_chip.fwnode = fwnode;
        bank->gpio_chip.parent = dev;
        bank->bank_nr = bank_nr;
        bank->bank_ioport_nr = bank_ioport_nr;
        bank->secure_control = pctl->match_data->secure_control;
        bank->io_sync_control = pctl->match_data->io_sync_control;
        bank->rif_control = pctl->match_data->rif_control;
        spin_lock_init(&bank->lock);

        if (pctl->domain) {
                /* create irq hierarchical domain */
                bank->fwnode = fwnode;

                bank->domain = irq_domain_create_hierarchy(pctl->domain, 0, STM32_GPIO_IRQ_LINE,
                                                           bank->fwnode, &stm32_gpio_domain_ops,
                                                           bank);

                if (!bank->domain)
                        return -ENODEV;
        }

        names = devm_kcalloc(dev, npins, sizeof(char *), GFP_KERNEL);
        if (!names)
                return -ENOMEM;

        for (i = 0; i < npins; i++) {
                stm32_pin = stm32_pctrl_get_desc_pin_from_gpio(pctl, bank, i);
                if (stm32_pin && stm32_pin->pin.name) {
                        names[i] = devm_kasprintf(dev, GFP_KERNEL, "%s", stm32_pin->pin.name);
                        if (!names[i])
                                return -ENOMEM;
                } else {
                        names[i] = NULL;
                }
        }

        bank->gpio_chip.names = (const char * const *)names;

        err = gpiochip_add_data(&bank->gpio_chip, bank);
        if (err) {
                dev_err(dev, "Failed to add gpiochip(%d)!\n", bank_nr);
                return err;
        }

        dev_info(dev, "%s bank added\n", bank->gpio_chip.label);
        return 0;
}

static struct irq_domain *stm32_pctrl_get_irq_domain(struct platform_device *pdev)
{
        struct device_node *np = pdev->dev.of_node;
        struct device_node *parent;
        struct irq_domain *domain;

        if (!of_property_present(np, "interrupt-parent"))
                return NULL;

        parent = of_irq_find_parent(np);
        if (!parent)
                return ERR_PTR(-ENXIO);

        domain = irq_find_host(parent);
        of_node_put(parent);
        if (!domain)
                /* domain not registered yet */
                return ERR_PTR(-EPROBE_DEFER);

        return domain;
}

static int stm32_pctrl_dt_setup_irq(struct platform_device *pdev,
                           struct stm32_pinctrl *pctl)
{
        struct device_node *np = pdev->dev.of_node;
        struct device *dev = &pdev->dev;
        struct regmap *rm;
        int offset, ret, i;
        int mask, mask_width;

        pctl->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
        if (IS_ERR(pctl->regmap))
                return PTR_ERR(pctl->regmap);

        rm = pctl->regmap;

        ret = of_property_read_u32_index(np, "st,syscfg", 1, &offset);
        if (ret)
                return ret;

        ret = of_property_read_u32_index(np, "st,syscfg", 2, &mask);
        if (ret)
                mask = SYSCFG_IRQMUX_MASK;

        mask_width = fls(mask);

        for (i = 0; i < STM32_GPIO_PINS_PER_BANK; i++) {
                struct reg_field mux;

                mux.reg = offset + (i / 4) * 4;
                mux.lsb = (i % 4) * mask_width;
                mux.msb = mux.lsb + mask_width - 1;

                dev_dbg(dev, "irqmux%d: reg:%#x, lsb:%d, msb:%d\n",
                        i, mux.reg, mux.lsb, mux.msb);

                pctl->irqmux[i] = devm_regmap_field_alloc(dev, rm, mux);
                if (IS_ERR(pctl->irqmux[i]))
                        return PTR_ERR(pctl->irqmux[i]);
        }

        return 0;
}

static int stm32_pctrl_build_state(struct platform_device *pdev)
{
        struct stm32_pinctrl *pctl = platform_get_drvdata(pdev);
        int i;

        pctl->ngroups = pctl->npins;

        /* Allocate groups */
        pctl->groups = devm_kcalloc(&pdev->dev, pctl->ngroups,
                                    sizeof(*pctl->groups), GFP_KERNEL);
        if (!pctl->groups)
                return -ENOMEM;

        /* We assume that one pin is one group, use pin name as group name. */
        pctl->grp_names = devm_kcalloc(&pdev->dev, pctl->ngroups,
                                       sizeof(*pctl->grp_names), GFP_KERNEL);
        if (!pctl->grp_names)
                return -ENOMEM;

        for (i = 0; i < pctl->npins; i++) {
                const struct stm32_desc_pin *pin = pctl->pins + i;
                struct stm32_pinctrl_group *group = pctl->groups + i;

                group->name = pin->pin.name;
                group->pin = pin->pin.number;
                pctl->grp_names[i] = pin->pin.name;
        }

        return 0;
}

static int stm32_pctrl_create_pins_tab(struct stm32_pinctrl *pctl,
                                       struct stm32_desc_pin *pins)
{
        const struct stm32_desc_pin *p;
        int i, nb_pins_available = 0;

        for (i = 0; i < pctl->match_data->npins; i++) {
                p = pctl->match_data->pins + i;
                if (pctl->pkg && !(pctl->pkg & p->pkg))
                        continue;
                pins->pin = p->pin;
                memcpy((struct stm32_desc_pin *)pins->functions, p->functions,
                       STM32_CONFIG_NUM * sizeof(struct stm32_desc_function));
                pins++;
                nb_pins_available++;
        }

        pctl->npins = nb_pins_available;

        return 0;
}

int stm32_pctl_probe(struct platform_device *pdev)
{
        const struct stm32_pinctrl_match_data *match_data;
        struct fwnode_handle *child;
        struct device *dev = &pdev->dev;
        struct stm32_pinctrl *pctl;
        struct pinctrl_pin_desc *pins;
        int i, ret, hwlock_id;
        unsigned int banks;

        match_data = device_get_match_data(dev);
        if (!match_data)
                return -EINVAL;

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

        platform_set_drvdata(pdev, pctl);

        /* check for IRQ controller (may require deferred probe) */
        pctl->domain = stm32_pctrl_get_irq_domain(pdev);
        if (IS_ERR(pctl->domain))
                return PTR_ERR(pctl->domain);
        if (!pctl->domain)
                dev_warn(dev, "pinctrl without interrupt support\n");

        /* hwspinlock is optional */
        hwlock_id = of_hwspin_lock_get_id(pdev->dev.of_node, 0);
        if (hwlock_id < 0) {
                if (hwlock_id == -EPROBE_DEFER)
                        return hwlock_id;
        } else {
                pctl->hwlock = devm_hwspin_lock_request_specific(dev, hwlock_id);
        }

        spin_lock_init(&pctl->irqmux_lock);

        pctl->dev = dev;
        pctl->match_data = match_data;

        /*  get optional package information */
        if (!device_property_read_u32(dev, "st,package", &pctl->pkg))
                dev_dbg(pctl->dev, "package detected: %x\n", pctl->pkg);

        pctl->pins = devm_kcalloc(pctl->dev, pctl->match_data->npins,
                                  sizeof(*pctl->pins), GFP_KERNEL);
        if (!pctl->pins)
                return -ENOMEM;

        ret = stm32_pctrl_create_pins_tab(pctl, pctl->pins);
        if (ret)
                return ret;

        ret = stm32_pctrl_build_state(pdev);
        if (ret) {
                dev_err(dev, "build state failed: %d\n", ret);
                return -EINVAL;
        }

        if (pctl->domain) {
                ret = stm32_pctrl_dt_setup_irq(pdev, pctl);
                if (ret)
                        return ret;
        }

        pins = devm_kcalloc(&pdev->dev, pctl->npins, sizeof(*pins),
                            GFP_KERNEL);
        if (!pins)
                return -ENOMEM;

        for (i = 0; i < pctl->npins; i++)
                pins[i] = pctl->pins[i].pin;

        pctl->pctl_desc.name = dev_name(&pdev->dev);
        pctl->pctl_desc.owner = THIS_MODULE;
        pctl->pctl_desc.pins = pins;
        pctl->pctl_desc.npins = pctl->npins;
        pctl->pctl_desc.link_consumers = true;
        pctl->pctl_desc.confops = &stm32_pconf_ops;
        pctl->pctl_desc.pctlops = &stm32_pctrl_ops;
        pctl->pctl_desc.pmxops = &stm32_pmx_ops;
        pctl->pctl_desc.num_custom_params = ARRAY_SIZE(stm32_gpio_bindings);
        pctl->pctl_desc.custom_params = stm32_gpio_bindings;
        pctl->dev = &pdev->dev;

        pctl->pctl_dev = devm_pinctrl_register(&pdev->dev, &pctl->pctl_desc,
                                               pctl);

        if (IS_ERR(pctl->pctl_dev)) {
                dev_err(&pdev->dev, "Failed pinctrl registration\n");
                return PTR_ERR(pctl->pctl_dev);
        }

        banks = gpiochip_node_count(dev);
        if (!banks) {
                dev_err(dev, "at least one GPIO bank is required\n");
                return -EINVAL;
        }
        pctl->banks = devm_kcalloc(dev, banks, sizeof(*pctl->banks),
                        GFP_KERNEL);
        if (!pctl->banks)
                return -ENOMEM;

        pctl->clks = devm_kcalloc(dev, banks, sizeof(*pctl->clks),
                                  GFP_KERNEL);
        if (!pctl->clks)
                return -ENOMEM;

        i = 0;
        for_each_gpiochip_node(dev, child) {
                struct stm32_gpio_bank *bank = &pctl->banks[i];
                struct device_node *np = to_of_node(child);

                bank->rstc = of_reset_control_get_exclusive(np, NULL);
                if (PTR_ERR(bank->rstc) == -EPROBE_DEFER) {
                        fwnode_handle_put(child);
                        return -EPROBE_DEFER;
                }

                pctl->clks[i].clk = of_clk_get_by_name(np, NULL);
                if (IS_ERR(pctl->clks[i].clk)) {
                        fwnode_handle_put(child);
                        return dev_err_probe(dev, PTR_ERR(pctl->clks[i].clk),
                                             "failed to get clk\n");
                }
                pctl->clks[i].id = "pctl";
                i++;
        }

        ret = clk_bulk_prepare_enable(banks, pctl->clks);
        if (ret) {
                dev_err(dev, "failed to prepare_enable clk (%d)\n", ret);
                return ret;
        }

        for_each_gpiochip_node(dev, child) {
                ret = stm32_gpiolib_register_bank(pctl, child);
                if (ret) {
                        fwnode_handle_put(child);
                        goto err_register;
                }

                pctl->nbanks++;
        }

        dev_info(dev, "Pinctrl STM32 initialized\n");

        return 0;
err_register:
        for (i = 0; i < pctl->nbanks; i++) {
                struct stm32_gpio_bank *bank = &pctl->banks[i];

                gpiochip_remove(&bank->gpio_chip);
        }

        clk_bulk_disable_unprepare(banks, pctl->clks);
        return ret;
}
EXPORT_SYMBOL(stm32_pctl_probe);

static int __maybe_unused stm32_pinctrl_restore_gpio_regs(
                                        struct stm32_pinctrl *pctl, u32 pin)
{
        const struct pin_desc *desc = pin_desc_get(pctl->pctl_dev, pin);
        u32 mode, offset = stm32_gpio_pin(pin);
        struct pinctrl_gpio_range *range;
        struct stm32_gpio_bank *bank;
        bool pin_is_irq;
        int ret;

        range = pinctrl_find_gpio_range_from_pin(pctl->pctl_dev, pin);
        if (!range)
                return 0;

        bank = gpiochip_get_data(range->gc);

        if (!gpiochip_line_is_valid(range->gc, offset))
                return 0;

        if (bank->rif_control && !stm32_gpio_rif_acquire_semaphore(bank, offset)) {
                dev_err(pctl->dev, "pin %d not available.\n", offset);
                return -EACCES;
        }

        pin_is_irq = gpiochip_line_is_irq(range->gc, offset);

        if (!desc || (!pin_is_irq && !desc->gpio_owner))
                return 0;

        mode = bank->pin_backup[offset].mode;
        ret = stm32_pmx_set_mode(bank, offset, mode, bank->pin_backup[offset].alt);
        if (ret)
                return ret;

        if (mode == 1)
                __stm32_gpio_set(bank, offset, bank->pin_backup[offset].value);

        ret = stm32_pconf_set_driving(bank, offset, bank->pin_backup[offset].drive);
        if (ret)
                return ret;

        ret = stm32_pconf_set_speed(bank, offset, bank->pin_backup[offset].speed);
        if (ret)
                return ret;

        ret = stm32_pconf_set_bias(bank, offset, bank->pin_backup[offset].bias);
        if (ret)
                return ret;

        if (bank->io_sync_control) {
                bool is_input = bank->pin_backup[offset].advcfg & STM32_GPIO_ADVCFGR_DLYPATH_MASK;

                ret = stm32_pconf_set_skew_delay(bank, offset,
                                                 bank->pin_backup[offset].skew_delay,
                                                 is_input);
                if (ret)
                        return ret;

                ret = stm32_pconf_set_advcfgr(bank, offset, STM32_GPIO_ADVCFGR_IO_SYNC_MASK,
                                              bank->pin_backup[offset].advcfg);
                if (ret)
                        return ret;
        }

        if (pin_is_irq)
                regmap_field_write(pctl->irqmux[offset], bank->bank_ioport_nr);

        return 0;
}

int __maybe_unused stm32_pinctrl_suspend(struct device *dev)
{
        struct stm32_pinctrl *pctl = dev_get_drvdata(dev);

        clk_bulk_disable(pctl->nbanks, pctl->clks);

        return 0;
}
EXPORT_SYMBOL(stm32_pinctrl_suspend);

int __maybe_unused stm32_pinctrl_resume(struct device *dev)
{
        struct stm32_pinctrl *pctl = dev_get_drvdata(dev);
        struct stm32_pinctrl_group *g = pctl->groups;
        int i, ret;

        ret = clk_bulk_enable(pctl->nbanks, pctl->clks);
        if (ret)
                return ret;

        for (i = 0; i < pctl->ngroups; i++, g++)
                stm32_pinctrl_restore_gpio_regs(pctl, g->pin);

        return 0;
}
EXPORT_SYMBOL(stm32_pinctrl_resume);

MODULE_AUTHOR("Alexandre Torgue <alexandre.torgue@foss.st.com>");
MODULE_DESCRIPTION("STM32 core pinctrl driver");
MODULE_LICENSE("GPL");