Merge tag 'trace-v4.15-rc4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rosted...

[mirror_ubuntu-bionic-kernel.git] / drivers / pinctrl / stm32 / pinctrl-stm32.c

/*
 * Copyright (C) Maxime Coquelin 2015
 * Author:  Maxime Coquelin <mcoquelin.stm32@gmail.com>
 * License terms:  GNU General Public License (GPL), version 2
 *
 * Heavily based on Mediatek's pinctrl driver
 */
#include <linux/clk.h>
#include <linux/gpio/driver.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_device.h>
#include <linux/of_irq.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pinctrl/machine.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinmux.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/slab.h>

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

#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_PINS_PER_BANK 16
#define STM32_GPIO_IRQ_LINE      16

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

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",
};

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

struct stm32_gpio_bank {
        void __iomem *base;
        struct clk *clk;
        spinlock_t lock;
        struct gpio_chip gpio_chip;
        struct pinctrl_gpio_range range;
        struct fwnode_handle *fwnode;
        struct irq_domain *domain;
        u32 bank_nr;
};

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;
        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];
};

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;
}

/* GPIO functions */

static inline void __stm32_gpio_set(struct stm32_gpio_bank *bank,
        unsigned offset, int value)
{
        if (!value)
                offset += STM32_GPIO_PINS_PER_BANK;

        clk_enable(bank->clk);

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

        clk_disable(bank->clk);
}

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;
        }

        return pinctrl_gpio_request(chip->base + offset);
}

static void stm32_gpio_free(struct gpio_chip *chip, unsigned offset)
{
        pinctrl_gpio_free(chip->base + offset);
}

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

        clk_enable(bank->clk);

        ret = !!(readl_relaxed(bank->base + STM32_GPIO_IDR) & BIT(offset));

        clk_disable(bank->clk);

        return ret;
}

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

        __stm32_gpio_set(bank, offset, value);
}

static int stm32_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
        return pinctrl_gpio_direction_input(chip->base + offset);
}

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);
        pinctrl_gpio_direction_output(chip->base + offset);

        return 0;
}


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 = 1;
        else if ((alt == 0) && (mode == 1))
                ret = 0;
        else
                ret = -EINVAL;

        return ret;
}

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        = stm32_gpio_direction_input,
        .direction_output       = stm32_gpio_direction_output,
        .to_irq                 = stm32_gpio_to_irq,
        .get_direction          = stm32_gpio_get_direction,
};

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 = stm32_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 struct irq_chip stm32_gpio_irq_chip = {
        .name           = "stm32gpio",
        .irq_eoi        = irq_chip_eoi_parent,
        .irq_mask       = irq_chip_mask_parent,
        .irq_unmask     = irq_chip_unmask_parent,
        .irq_set_type   = irq_chip_set_type_parent,
        .irq_request_resources = stm32_gpio_irq_request_resources,
        .irq_release_resources = stm32_gpio_irq_release_resources,
};

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);

        regmap_field_write(pctl->irqmux[irq_data->hwirq], bank->bank_nr);
        return 0;
}

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;
        irq_hw_number_t hwirq;

        hwirq = fwspec->param[0];
        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 const struct irq_domain_ops stm32_gpio_domain_ops = {
        .translate      = stm32_gpio_domain_translate,
        .alloc          = stm32_gpio_domain_alloc,
        .free           = irq_domain_free_irqs_common,
        .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;

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

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

                while (func && func->name) {
                        if (func->num == fnum)
                                return true;
                        func++;
                }

                break;
        }

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

        pctl = pinctrl_dev_get_drvdata(pctldev);

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

        reserve = num_pins * maps_per_pin;

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

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

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

                if (!stm32_pctrl_is_function_valid(pctl, pin, func)) {
                        dev_err(pctl->dev, "invalid function.\n");
                        return -EINVAL;
                }

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

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

                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)
                                return err;
                }
        }

        return 0;
}

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

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

        for_each_child_of_node(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 void stm32_pmx_set_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;
        unsigned long flags;

        clk_enable(bank->clk);
        spin_lock_irqsave(&bank->lock, flags);

        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);

        spin_unlock_irqrestore(&bank->lock, flags);
        clk_disable(bank->clk);
}

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;
        unsigned long flags;

        clk_enable(bank->clk);
        spin_lock_irqsave(&bank->lock, flags);

        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);

        spin_unlock_irqrestore(&bank->lock, flags);
        clk_disable(bank->clk);
}

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) {
                dev_err(pctl->dev, "invalid function %d on group %d .\n",
                                function, group);
                return -EINVAL;
        }

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

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

        stm32_pmx_set_mode(bank, pin, mode, alt);

        return 0;
}

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);

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

        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,
        .strict                 = true,
};

/* Pinconf functions */

static void stm32_pconf_set_driving(struct stm32_gpio_bank *bank,
        unsigned offset, u32 drive)
{
        unsigned long flags;
        u32 val;

        clk_enable(bank->clk);
        spin_lock_irqsave(&bank->lock, flags);

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

        spin_unlock_irqrestore(&bank->lock, flags);
        clk_disable(bank->clk);
}

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

        clk_enable(bank->clk);
        spin_lock_irqsave(&bank->lock, flags);

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

        spin_unlock_irqrestore(&bank->lock, flags);
        clk_disable(bank->clk);

        return (val >> offset);
}

static void stm32_pconf_set_speed(struct stm32_gpio_bank *bank,
        unsigned offset, u32 speed)
{
        unsigned long flags;
        u32 val;

        clk_enable(bank->clk);
        spin_lock_irqsave(&bank->lock, flags);

        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);

        spin_unlock_irqrestore(&bank->lock, flags);
        clk_disable(bank->clk);
}

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

        clk_enable(bank->clk);
        spin_lock_irqsave(&bank->lock, flags);

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

        spin_unlock_irqrestore(&bank->lock, flags);
        clk_disable(bank->clk);

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

static void stm32_pconf_set_bias(struct stm32_gpio_bank *bank,
        unsigned offset, u32 bias)
{
        unsigned long flags;
        u32 val;

        clk_enable(bank->clk);
        spin_lock_irqsave(&bank->lock, flags);

        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);

        spin_unlock_irqrestore(&bank->lock, flags);
        clk_disable(bank->clk);
}

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

        clk_enable(bank->clk);
        spin_lock_irqsave(&bank->lock, flags);

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

        spin_unlock_irqrestore(&bank->lock, flags);
        clk_disable(bank->clk);

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

static bool stm32_pconf_get(struct stm32_gpio_bank *bank,
        unsigned int offset, bool dir)
{
        unsigned long flags;
        u32 val;

        clk_enable(bank->clk);
        spin_lock_irqsave(&bank->lock, flags);

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

        spin_unlock_irqrestore(&bank->lock, flags);
        clk_disable(bank->clk);

        return val;
}

static int stm32_pconf_parse_conf(struct pinctrl_dev *pctldev,
                unsigned int pin, enum pin_config_param param,
                enum pin_config_param arg)
{
        struct pinctrl_gpio_range *range;
        struct stm32_gpio_bank *bank;
        int offset, ret = 0;

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

        switch (param) {
        case PIN_CONFIG_DRIVE_PUSH_PULL:
                stm32_pconf_set_driving(bank, offset, 0);
                break;
        case PIN_CONFIG_DRIVE_OPEN_DRAIN:
                stm32_pconf_set_driving(bank, offset, 1);
                break;
        case PIN_CONFIG_SLEW_RATE:
                stm32_pconf_set_speed(bank, offset, arg);
                break;
        case PIN_CONFIG_BIAS_DISABLE:
                stm32_pconf_set_bias(bank, offset, 0);
                break;
        case PIN_CONFIG_BIAS_PULL_UP:
                stm32_pconf_set_bias(bank, offset, 1);
                break;
        case PIN_CONFIG_BIAS_PULL_DOWN:
                stm32_pconf_set_bias(bank, offset, 2);
                break;
        case PIN_CONFIG_OUTPUT:
                __stm32_gpio_set(bank, offset, arg);
                ret = stm32_pmx_gpio_set_direction(pctldev, range, pin, false);
                break;
        default:
                ret = -EINVAL;
        }

        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++) {
                ret = stm32_pconf_parse_conf(pctldev, g->pin,
                        pinconf_to_config_param(configs[i]),
                        pinconf_to_config_argument(configs[i]));
                if (ret < 0)
                        return ret;

                g->config = configs[i];
        }

        return 0;
}

static void stm32_pconf_dbg_show(struct pinctrl_dev *pctldev,
                                 struct seq_file *s,
                                 unsigned int pin)
{
        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);
        bank = gpiochip_get_data(range->gc);
        offset = stm32_gpio_pin(pin);

        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",
                           val ? "high" : "low",
                           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",
                           val ? "high" : "low",
                           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);
                seq_printf(s, "%d - %s - %s - %s %s", alt,
                           drive ? "open drain" : "push pull",
                           biasing[bias],
                           speeds[speed], "speed");
                break;

        /* analog */
        case 3:
                break;
        }
}


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_dbg_show    = stm32_pconf_dbg_show,
};

static int stm32_gpiolib_register_bank(struct stm32_pinctrl *pctl,
        struct device_node *np)
{
        struct stm32_gpio_bank *bank = &pctl->banks[pctl->nbanks];
        struct pinctrl_gpio_range *range = &bank->range;
        struct of_phandle_args args;
        struct device *dev = pctl->dev;
        struct resource res;
        struct reset_control *rstc;
        int npins = STM32_GPIO_PINS_PER_BANK;
        int bank_nr, err;

        rstc = of_reset_control_get_exclusive(np, NULL);
        if (!IS_ERR(rstc))
                reset_control_deassert(rstc);

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

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

        bank->clk = of_clk_get_by_name(np, NULL);
        if (IS_ERR(bank->clk)) {
                dev_err(dev, "failed to get clk (%ld)\n", PTR_ERR(bank->clk));
                return PTR_ERR(bank->clk);
        }

        err = clk_prepare(bank->clk);
        if (err) {
                dev_err(dev, "failed to prepare clk (%d)\n", err);
                return err;
        }

        bank->gpio_chip = stm32_gpio_template;

        of_property_read_string(np, "st,bank-name", &bank->gpio_chip.label);

        if (!of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 0, &args)) {
                bank_nr = args.args[1] / STM32_GPIO_PINS_PER_BANK;
                bank->gpio_chip.base = args.args[1];
        } 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);
        }
        bank->gpio_chip.base = bank_nr * STM32_GPIO_PINS_PER_BANK;

        bank->gpio_chip.ngpio = npins;
        bank->gpio_chip.of_node = np;
        bank->gpio_chip.parent = dev;
        bank->bank_nr = bank_nr;
        spin_lock_init(&bank->lock);

        /* create irq hierarchical domain */
        bank->fwnode = of_node_to_fwnode(np);

        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;

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

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

        pctl->domain = irq_find_host(parent);
        if (!pctl->domain)
                return -ENXIO;

        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;

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

                mux.reg = offset + (i / 4) * 4;
                mux.lsb = (i % 4) * 4;
                mux.msb = mux.lsb + 3;

                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->match_data->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->match_data->npins; i++) {
                const struct stm32_desc_pin *pin = pctl->match_data->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;
}

int stm32_pctl_probe(struct platform_device *pdev)
{
        struct device_node *np = pdev->dev.of_node;
        struct device_node *child;
        const struct of_device_id *match;
        struct device *dev = &pdev->dev;
        struct stm32_pinctrl *pctl;
        struct pinctrl_pin_desc *pins;
        int i, ret, banks = 0;

        if (!np)
                return -EINVAL;

        match = of_match_device(dev->driver->of_match_table, dev);
        if (!match || !match->data)
                return -EINVAL;

        if (!of_find_property(np, "pins-are-numbered", NULL)) {
                dev_err(dev, "only support pins-are-numbered format\n");
                return -EINVAL;
        }

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

        platform_set_drvdata(pdev, pctl);

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

        if (of_find_property(np, "interrupt-parent", NULL)) {
                ret = stm32_pctrl_dt_setup_irq(pdev, pctl);
                if (ret)
                        return ret;
        }

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

        for (i = 0; i < pctl->match_data->npins; i++)
                pins[i] = pctl->match_data->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->match_data->npins;
        pctl->pctl_desc.confops = &stm32_pconf_ops;
        pctl->pctl_desc.pctlops = &stm32_pctrl_ops;
        pctl->pctl_desc.pmxops = &stm32_pmx_ops;
        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);
        }

        for_each_child_of_node(np, child)
                if (of_property_read_bool(child, "gpio-controller"))
                        banks++;

        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;

        for_each_child_of_node(np, child) {
                if (of_property_read_bool(child, "gpio-controller")) {
                        ret = stm32_gpiolib_register_bank(pctl, child);
                        if (ret)
                                return ret;

                        pctl->nbanks++;
                }
        }

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

        return 0;
}