/*
 * mt65xx pinctrl driver based on Allwinner A1X pinctrl driver.
 * Copyright (c) 2014 MediaTek Inc.
 * Author: Hongzhou.Yang <hongzhou.yang@mediatek.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/io.h>
#include <linux/gpio/driver.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/slab.h>
#include <linux/bitops.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/pm.h>
#include <dt-bindings/pinctrl/mt65xx.h>

#include "../core.h"
#include "../pinconf.h"
#include "../pinctrl-utils.h"
#include "mtk-eint.h"
#include "pinctrl-mtk-common.h"

#define MAX_GPIO_MODE_PER_REG 5
#define GPIO_MODE_BITS        3
#define GPIO_MODE_PREFIX "GPIO"

static const char * const mtk_gpio_functions[] = {
        "func0", "func1", "func2", "func3",
        "func4", "func5", "func6", "func7",
        "func8", "func9", "func10", "func11",
        "func12", "func13", "func14", "func15",
};

/*
 * There are two base address for pull related configuration
 * in mt8135, and different GPIO pins use different base address.
 * When pin number greater than type1_start and less than type1_end,
 * should use the second base address.
 */
static struct regmap *mtk_get_regmap(struct mtk_pinctrl *pctl,
                unsigned long pin)
{
        if (pin >= pctl->devdata->type1_start && pin < pctl->devdata->type1_end)
                return pctl->regmap2;
        return pctl->regmap1;
}

static unsigned int mtk_get_port(struct mtk_pinctrl *pctl, unsigned long pin)
{
        /* Different SoC has different mask and port shift. */
        return ((pin >> 4) & pctl->devdata->port_mask)
                        << pctl->devdata->port_shf;
}

static int mtk_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
                        struct pinctrl_gpio_range *range, unsigned offset,
                        bool input)
{
        unsigned int reg_addr;
        unsigned int bit;
        struct mtk_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);

        reg_addr = mtk_get_port(pctl, offset) + pctl->devdata->dir_offset;
        bit = BIT(offset & 0xf);

        if (pctl->devdata->spec_dir_set)
                pctl->devdata->spec_dir_set(&reg_addr, offset);

        if (input)
                /* Different SoC has different alignment offset. */
                reg_addr = CLR_ADDR(reg_addr, pctl);
        else
                reg_addr = SET_ADDR(reg_addr, pctl);

        regmap_write(mtk_get_regmap(pctl, offset), reg_addr, bit);
        return 0;
}

static void mtk_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
        unsigned int reg_addr;
        unsigned int bit;
        struct mtk_pinctrl *pctl = gpiochip_get_data(chip);

        reg_addr = mtk_get_port(pctl, offset) + pctl->devdata->dout_offset;
        bit = BIT(offset & 0xf);

        if (value)
                reg_addr = SET_ADDR(reg_addr, pctl);
        else
                reg_addr = CLR_ADDR(reg_addr, pctl);

        regmap_write(mtk_get_regmap(pctl, offset), reg_addr, bit);
}

static int mtk_pconf_set_ies_smt(struct mtk_pinctrl *pctl, unsigned pin,
                int value, enum pin_config_param arg)
{
        unsigned int reg_addr, offset;
        unsigned int bit;

        /**
         * Due to some soc are not support ies/smt config, add this special
         * control to handle it.
         */
        if (!pctl->devdata->spec_ies_smt_set &&
                pctl->devdata->ies_offset == MTK_PINCTRL_NOT_SUPPORT &&
                        arg == PIN_CONFIG_INPUT_ENABLE)
                return -EINVAL;

        if (!pctl->devdata->spec_ies_smt_set &&
                pctl->devdata->smt_offset == MTK_PINCTRL_NOT_SUPPORT &&
                        arg == PIN_CONFIG_INPUT_SCHMITT_ENABLE)
                return -EINVAL;

        /*
         * Due to some pins are irregular, their input enable and smt
         * control register are discontinuous, so we need this special handle.
         */
        if (pctl->devdata->spec_ies_smt_set) {
                return pctl->devdata->spec_ies_smt_set(mtk_get_regmap(pctl, pin),
                        pin, pctl->devdata->port_align, value, arg);
        }

        bit = BIT(pin & 0xf);

        if (arg == PIN_CONFIG_INPUT_ENABLE)
                offset = pctl->devdata->ies_offset;
        else
                offset = pctl->devdata->smt_offset;

        if (value)
                reg_addr = SET_ADDR(mtk_get_port(pctl, pin) + offset, pctl);
        else
                reg_addr = CLR_ADDR(mtk_get_port(pctl, pin) + offset, pctl);

        regmap_write(mtk_get_regmap(pctl, pin), reg_addr, bit);
        return 0;
}

int mtk_pconf_spec_set_ies_smt_range(struct regmap *regmap,
                const struct mtk_pin_ies_smt_set *ies_smt_infos, unsigned int info_num,
                unsigned int pin, unsigned char align, int value)
{
        unsigned int i, reg_addr, bit;

        for (i = 0; i < info_num; i++) {
                if (pin >= ies_smt_infos[i].start &&
                                pin <= ies_smt_infos[i].end) {
                        break;
                }
        }

        if (i == info_num)
                return -EINVAL;

        if (value)
                reg_addr = ies_smt_infos[i].offset + align;
        else
                reg_addr = ies_smt_infos[i].offset + (align << 1);

        bit = BIT(ies_smt_infos[i].bit);
        regmap_write(regmap, reg_addr, bit);
        return 0;
}

static const struct mtk_pin_drv_grp *mtk_find_pin_drv_grp_by_pin(
                struct mtk_pinctrl *pctl,  unsigned long pin) {
        int i;

        for (i = 0; i < pctl->devdata->n_pin_drv_grps; i++) {
                const struct mtk_pin_drv_grp *pin_drv =
                                pctl->devdata->pin_drv_grp + i;
                if (pin == pin_drv->pin)
                        return pin_drv;
        }

        return NULL;
}

static int mtk_pconf_set_driving(struct mtk_pinctrl *pctl,
                unsigned int pin, unsigned char driving)
{
        const struct mtk_pin_drv_grp *pin_drv;
        unsigned int val;
        unsigned int bits, mask, shift;
        const struct mtk_drv_group_desc *drv_grp;

        if (pin >= pctl->devdata->npins)
                return -EINVAL;

        pin_drv = mtk_find_pin_drv_grp_by_pin(pctl, pin);
        if (!pin_drv || pin_drv->grp > pctl->devdata->n_grp_cls)
                return -EINVAL;

        drv_grp = pctl->devdata->grp_desc + pin_drv->grp;
        if (driving >= drv_grp->min_drv && driving <= drv_grp->max_drv
                && !(driving % drv_grp->step)) {
                val = driving / drv_grp->step - 1;
                bits = drv_grp->high_bit - drv_grp->low_bit + 1;
                mask = BIT(bits) - 1;
                shift = pin_drv->bit + drv_grp->low_bit;
                mask <<= shift;
                val <<= shift;
                return regmap_update_bits(mtk_get_regmap(pctl, pin),
                                pin_drv->offset, mask, val);
        }

        return -EINVAL;
}

int mtk_pctrl_spec_pull_set_samereg(struct regmap *regmap,
                const struct mtk_pin_spec_pupd_set_samereg *pupd_infos,
                unsigned int info_num, unsigned int pin,
                unsigned char align, bool isup, unsigned int r1r0)
{
        unsigned int i;
        unsigned int reg_pupd, reg_set, reg_rst;
        unsigned int bit_pupd, bit_r0, bit_r1;
        const struct mtk_pin_spec_pupd_set_samereg *spec_pupd_pin;
        bool find = false;

        for (i = 0; i < info_num; i++) {
                if (pin == pupd_infos[i].pin) {
                        find = true;
                        break;
                }
        }

        if (!find)
                return -EINVAL;

        spec_pupd_pin = pupd_infos + i;
        reg_set = spec_pupd_pin->offset + align;
        reg_rst = spec_pupd_pin->offset + (align << 1);

        if (isup)
                reg_pupd = reg_rst;
        else
                reg_pupd = reg_set;

        bit_pupd = BIT(spec_pupd_pin->pupd_bit);
        regmap_write(regmap, reg_pupd, bit_pupd);

        bit_r0 = BIT(spec_pupd_pin->r0_bit);
        bit_r1 = BIT(spec_pupd_pin->r1_bit);

        switch (r1r0) {
        case MTK_PUPD_SET_R1R0_00:
                regmap_write(regmap, reg_rst, bit_r0);
                regmap_write(regmap, reg_rst, bit_r1);
                break;
        case MTK_PUPD_SET_R1R0_01:
                regmap_write(regmap, reg_set, bit_r0);
                regmap_write(regmap, reg_rst, bit_r1);
                break;
        case MTK_PUPD_SET_R1R0_10:
                regmap_write(regmap, reg_rst, bit_r0);
                regmap_write(regmap, reg_set, bit_r1);
                break;
        case MTK_PUPD_SET_R1R0_11:
                regmap_write(regmap, reg_set, bit_r0);
                regmap_write(regmap, reg_set, bit_r1);
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static int mtk_pconf_set_pull_select(struct mtk_pinctrl *pctl,
                unsigned int pin, bool enable, bool isup, unsigned int arg)
{
        unsigned int bit;
        unsigned int reg_pullen, reg_pullsel, r1r0;
        int ret;

        /* Some pins' pull setting are very different,
         * they have separate pull up/down bit, R0 and R1
         * resistor bit, so we need this special handle.
         */
        if (pctl->devdata->spec_pull_set) {
                /* For special pins, bias-disable is set by R1R0,
                 * the parameter should be "MTK_PUPD_SET_R1R0_00".
                 */
                r1r0 = enable ? arg : MTK_PUPD_SET_R1R0_00;
                ret = pctl->devdata->spec_pull_set(mtk_get_regmap(pctl, pin),
                        pin, pctl->devdata->port_align, isup, r1r0);
                if (!ret)
                        return 0;
        }

        /* For generic pull config, default arg value should be 0 or 1. */
        if (arg != 0 && arg != 1) {
                dev_err(pctl->dev, "invalid pull-up argument %d on pin %d .\n",
                        arg, pin);
                return -EINVAL;
        }

        bit = BIT(pin & 0xf);
        if (enable)
                reg_pullen = SET_ADDR(mtk_get_port(pctl, pin) +
                        pctl->devdata->pullen_offset, pctl);
        else
                reg_pullen = CLR_ADDR(mtk_get_port(pctl, pin) +
                        pctl->devdata->pullen_offset, pctl);

        if (isup)
                reg_pullsel = SET_ADDR(mtk_get_port(pctl, pin) +
                        pctl->devdata->pullsel_offset, pctl);
        else
                reg_pullsel = CLR_ADDR(mtk_get_port(pctl, pin) +
                        pctl->devdata->pullsel_offset, pctl);

        regmap_write(mtk_get_regmap(pctl, pin), reg_pullen, bit);
        regmap_write(mtk_get_regmap(pctl, pin), reg_pullsel, bit);
        return 0;
}

static int mtk_pconf_parse_conf(struct pinctrl_dev *pctldev,
                unsigned int pin, enum pin_config_param param,
                enum pin_config_param arg)
{
        int ret = 0;
        struct mtk_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);

        switch (param) {
        case PIN_CONFIG_BIAS_DISABLE:
                ret = mtk_pconf_set_pull_select(pctl, pin, false, false, arg);
                break;
        case PIN_CONFIG_BIAS_PULL_UP:
                ret = mtk_pconf_set_pull_select(pctl, pin, true, true, arg);
                break;
        case PIN_CONFIG_BIAS_PULL_DOWN:
                ret = mtk_pconf_set_pull_select(pctl, pin, true, false, arg);
                break;
        case PIN_CONFIG_INPUT_ENABLE:
                mtk_pmx_gpio_set_direction(pctldev, NULL, pin, true);
                ret = mtk_pconf_set_ies_smt(pctl, pin, arg, param);
                break;
        case PIN_CONFIG_OUTPUT:
                mtk_gpio_set(pctl->chip, pin, arg);
                ret = mtk_pmx_gpio_set_direction(pctldev, NULL, pin, false);
                break;
        case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
                mtk_pmx_gpio_set_direction(pctldev, NULL, pin, true);
                ret = mtk_pconf_set_ies_smt(pctl, pin, arg, param);
                break;
        case PIN_CONFIG_DRIVE_STRENGTH:
                ret = mtk_pconf_set_driving(pctl, pin, arg);
                break;
        default:
                ret = -EINVAL;
        }

        return ret;
}

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

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

        return 0;
}

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

        for (i = 0; i < num_configs; i++) {
                ret = mtk_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 const struct pinconf_ops mtk_pconf_ops = {
        .pin_config_group_get   = mtk_pconf_group_get,
        .pin_config_group_set   = mtk_pconf_group_set,
};

static struct mtk_pinctrl_group *
mtk_pctrl_find_group_by_pin(struct mtk_pinctrl *pctl, u32 pin)
{
        int i;

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

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

        return NULL;
}

static const struct mtk_desc_function *mtk_pctrl_find_function_by_pin(
                struct mtk_pinctrl *pctl, u32 pin_num, u32 fnum)
{
        const struct mtk_desc_pin *pin = pctl->devdata->pins + pin_num;
        const struct mtk_desc_function *func = pin->functions;

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

        return NULL;
}

static bool mtk_pctrl_is_function_valid(struct mtk_pinctrl *pctl,
                u32 pin_num, u32 fnum)
{
        int i;

        for (i = 0; i < pctl->devdata->npins; i++) {
                const struct mtk_desc_pin *pin = pctl->devdata->pins + i;

                if (pin->pin.number == pin_num) {
                        const struct mtk_desc_function *func =
                                        pin->functions;

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

                        break;
                }
        }

        return false;
}

static int mtk_pctrl_dt_node_to_map_func(struct mtk_pinctrl *pctl,
                u32 pin, u32 fnum, struct mtk_pinctrl_group *grp,
                struct pinctrl_map **map, unsigned *reserved_maps,
                unsigned *num_maps)
{
        bool ret;

        if (*num_maps == *reserved_maps)
                return -ENOSPC;

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

        ret = mtk_pctrl_is_function_valid(pctl, pin, fnum);
        if (!ret) {
                dev_err(pctl->dev, "invalid function %d on pin %d .\n",
                                fnum, pin);
                return -EINVAL;
        }

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

        return 0;
}

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

        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 < 0)
                goto exit;

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

                pin = MTK_GET_PIN_NO(pinfunc);
                func = MTK_GET_PIN_FUNC(pinfunc);

                if (pin >= pctl->devdata->npins ||
                                func >= ARRAY_SIZE(mtk_gpio_functions)) {
                        dev_err(pctl->dev, "invalid pins value.\n");
                        err = -EINVAL;
                        goto exit;
                }

                grp = mtk_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 = mtk_pctrl_dt_node_to_map_func(pctl, pin, func, grp, map,
                                reserved_maps, num_maps);
                if (err < 0)
                        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 < 0)
                                goto exit;
                }
        }

        err = 0;

exit:
        kfree(configs);
        return err;
}

static int mtk_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 = mtk_pctrl_dt_subnode_to_map(pctldev, np, map,
                                &reserved_maps, num_maps);
                if (ret < 0) {
                        pinctrl_utils_free_map(pctldev, *map, *num_maps);
                        of_node_put(np);
                        return ret;
                }
        }

        return 0;
}

static int mtk_pctrl_get_groups_count(struct pinctrl_dev *pctldev)
{
        struct mtk_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);

        return pctl->ngroups;
}

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

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

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

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

        return 0;
}

static const struct pinctrl_ops mtk_pctrl_ops = {
        .dt_node_to_map         = mtk_pctrl_dt_node_to_map,
        .dt_free_map            = pinctrl_utils_free_map,
        .get_groups_count       = mtk_pctrl_get_groups_count,
        .get_group_name         = mtk_pctrl_get_group_name,
        .get_group_pins         = mtk_pctrl_get_group_pins,
};

static int mtk_pmx_get_funcs_cnt(struct pinctrl_dev *pctldev)
{
        return ARRAY_SIZE(mtk_gpio_functions);
}

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

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

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

        return 0;
}

static int mtk_pmx_set_mode(struct pinctrl_dev *pctldev,
                unsigned long pin, unsigned long mode)
{
        unsigned int reg_addr;
        unsigned char bit;
        unsigned int val;
        unsigned int mask = (1L << GPIO_MODE_BITS) - 1;
        struct mtk_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);

        if (pctl->devdata->spec_pinmux_set)
                pctl->devdata->spec_pinmux_set(mtk_get_regmap(pctl, pin),
                                        pin, mode);

        reg_addr = ((pin / MAX_GPIO_MODE_PER_REG) << pctl->devdata->port_shf)
                        + pctl->devdata->pinmux_offset;

        mode &= mask;
        bit = pin % MAX_GPIO_MODE_PER_REG;
        mask <<= (GPIO_MODE_BITS * bit);
        val = (mode << (GPIO_MODE_BITS * bit));
        return regmap_update_bits(mtk_get_regmap(pctl, pin),
                        reg_addr, mask, val);
}

static const struct mtk_desc_pin *
mtk_find_pin_by_eint_num(struct mtk_pinctrl *pctl, unsigned int eint_num)
{
        int i;
        const struct mtk_desc_pin *pin;

        for (i = 0; i < pctl->devdata->npins; i++) {
                pin = pctl->devdata->pins + i;
                if (pin->eint.eintnum == eint_num)
                        return pin;
        }

        return NULL;
}

static int mtk_pmx_set_mux(struct pinctrl_dev *pctldev,
                            unsigned function,
                            unsigned group)
{
        bool ret;
        const struct mtk_desc_function *desc;
        struct mtk_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
        struct mtk_pinctrl_group *g = pctl->groups + group;

        ret = mtk_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;
        }

        desc = mtk_pctrl_find_function_by_pin(pctl, g->pin, function);
        if (!desc)
                return -EINVAL;
        mtk_pmx_set_mode(pctldev, g->pin, desc->muxval);
        return 0;
}

static int mtk_pmx_find_gpio_mode(struct mtk_pinctrl *pctl,
                                unsigned offset)
{
        const struct mtk_desc_pin *pin = pctl->devdata->pins + offset;
        const struct mtk_desc_function *func = pin->functions;

        while (func && func->name) {
                if (!strncmp(func->name, GPIO_MODE_PREFIX,
                        sizeof(GPIO_MODE_PREFIX)-1))
                        return func->muxval;
                func++;
        }
        return -EINVAL;
}

static int mtk_pmx_gpio_request_enable(struct pinctrl_dev *pctldev,
                                    struct pinctrl_gpio_range *range,
                                    unsigned offset)
{
        int muxval;
        struct mtk_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);

        muxval = mtk_pmx_find_gpio_mode(pctl, offset);

        if (muxval < 0) {
                dev_err(pctl->dev, "invalid gpio pin %d.\n", offset);
                return -EINVAL;
        }

        mtk_pmx_set_mode(pctldev, offset, muxval);
        mtk_pconf_set_ies_smt(pctl, offset, 1, PIN_CONFIG_INPUT_ENABLE);

        return 0;
}

static const struct pinmux_ops mtk_pmx_ops = {
        .get_functions_count    = mtk_pmx_get_funcs_cnt,
        .get_function_name      = mtk_pmx_get_func_name,
        .get_function_groups    = mtk_pmx_get_func_groups,
        .set_mux                = mtk_pmx_set_mux,
        .gpio_set_direction     = mtk_pmx_gpio_set_direction,
        .gpio_request_enable    = mtk_pmx_gpio_request_enable,
};

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

static int mtk_gpio_direction_output(struct gpio_chip *chip,
                                        unsigned offset, int value)
{
        mtk_gpio_set(chip, offset, value);
        return pinctrl_gpio_direction_output(chip->base + offset);
}

static int mtk_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
{
        unsigned int reg_addr;
        unsigned int bit;
        unsigned int read_val = 0;

        struct mtk_pinctrl *pctl = gpiochip_get_data(chip);

        reg_addr =  mtk_get_port(pctl, offset) + pctl->devdata->dir_offset;
        bit = BIT(offset & 0xf);

        if (pctl->devdata->spec_dir_set)
                pctl->devdata->spec_dir_set(&reg_addr, offset);

        regmap_read(pctl->regmap1, reg_addr, &read_val);
        return !(read_val & bit);
}

static int mtk_gpio_get(struct gpio_chip *chip, unsigned offset)
{
        unsigned int reg_addr;
        unsigned int bit;
        unsigned int read_val = 0;
        struct mtk_pinctrl *pctl = gpiochip_get_data(chip);

        reg_addr = mtk_get_port(pctl, offset) +
                pctl->devdata->din_offset;

        bit = BIT(offset & 0xf);
        regmap_read(pctl->regmap1, reg_addr, &read_val);
        return !!(read_val & bit);
}

static int mtk_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
        struct mtk_pinctrl *pctl = gpiochip_get_data(chip);
        const struct mtk_desc_pin *pin;
        unsigned long eint_n;

        pin = pctl->devdata->pins + offset;
        if (pin->eint.eintnum == NO_EINT_SUPPORT)
                return -EINVAL;

        eint_n = pin->eint.eintnum;

        return mtk_eint_find_irq(pctl->eint, eint_n);
}

static int mtk_gpio_set_config(struct gpio_chip *chip, unsigned offset,
                               unsigned long config)
{
        struct mtk_pinctrl *pctl = gpiochip_get_data(chip);
        const struct mtk_desc_pin *pin;
        unsigned long eint_n;
        u32 debounce;

        if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
                return -ENOTSUPP;

        pin = pctl->devdata->pins + offset;
        if (pin->eint.eintnum == NO_EINT_SUPPORT)
                return -EINVAL;

        debounce = pinconf_to_config_argument(config);
        eint_n = pin->eint.eintnum;

        return mtk_eint_set_debounce(pctl->eint, eint_n, debounce);
}

static const struct gpio_chip mtk_gpio_chip = {
        .owner                  = THIS_MODULE,
        .request                = gpiochip_generic_request,
        .free                   = gpiochip_generic_free,
        .get_direction          = mtk_gpio_get_direction,
        .direction_input        = mtk_gpio_direction_input,
        .direction_output       = mtk_gpio_direction_output,
        .get                    = mtk_gpio_get,
        .set                    = mtk_gpio_set,
        .to_irq                 = mtk_gpio_to_irq,
        .set_config             = mtk_gpio_set_config,
        .of_gpio_n_cells        = 2,
};

static int mtk_eint_suspend(struct device *device)
{
        struct mtk_pinctrl *pctl = dev_get_drvdata(device);

        return mtk_eint_do_suspend(pctl->eint);
}

static int mtk_eint_resume(struct device *device)
{
        struct mtk_pinctrl *pctl = dev_get_drvdata(device);

        return mtk_eint_do_resume(pctl->eint);
}

const struct dev_pm_ops mtk_eint_pm_ops = {
        .suspend_noirq = mtk_eint_suspend,
        .resume_noirq = mtk_eint_resume,
};

static int mtk_pctrl_build_state(struct platform_device *pdev)
{
        struct mtk_pinctrl *pctl = platform_get_drvdata(pdev);
        int i;

        pctl->ngroups = pctl->devdata->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->devdata->npins; i++) {
                const struct mtk_desc_pin *pin = pctl->devdata->pins + i;
                struct mtk_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
mtk_xt_get_gpio_n(void *data, unsigned long eint_n, unsigned int *gpio_n,
                  struct gpio_chip **gpio_chip)
{
        struct mtk_pinctrl *pctl = (struct mtk_pinctrl *)data;
        const struct mtk_desc_pin *pin;

        pin = mtk_find_pin_by_eint_num(pctl, eint_n);
        if (!pin)
                return -EINVAL;

        *gpio_chip = pctl->chip;
        *gpio_n = pin->pin.number;

        return 0;
}

static int mtk_xt_get_gpio_state(void *data, unsigned long eint_n)
{
        struct mtk_pinctrl *pctl = (struct mtk_pinctrl *)data;
        const struct mtk_desc_pin *pin;

        pin = mtk_find_pin_by_eint_num(pctl, eint_n);
        if (!pin)
                return -EINVAL;

        return mtk_gpio_get(pctl->chip, pin->pin.number);
}

static int mtk_xt_set_gpio_as_eint(void *data, unsigned long eint_n)
{
        struct mtk_pinctrl *pctl = (struct mtk_pinctrl *)data;
        const struct mtk_desc_pin *pin;

        pin = mtk_find_pin_by_eint_num(pctl, eint_n);
        if (!pin)
                return -EINVAL;

        /* set mux to INT mode */
        mtk_pmx_set_mode(pctl->pctl_dev, pin->pin.number, pin->eint.eintmux);
        /* set gpio direction to input */
        mtk_pmx_gpio_set_direction(pctl->pctl_dev, NULL, pin->pin.number,
                                   true);
        /* set input-enable */
        mtk_pconf_set_ies_smt(pctl, pin->pin.number, 1,
                              PIN_CONFIG_INPUT_ENABLE);

        return 0;
}

static const struct mtk_eint_xt mtk_eint_xt = {
        .get_gpio_n = mtk_xt_get_gpio_n,
        .get_gpio_state = mtk_xt_get_gpio_state,
        .set_gpio_as_eint = mtk_xt_set_gpio_as_eint,
};

static int mtk_eint_init(struct mtk_pinctrl *pctl, struct platform_device *pdev)
{
        struct device_node *np = pdev->dev.of_node;
        struct resource *res;

        if (!of_property_read_bool(np, "interrupt-controller"))
                return -ENODEV;

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

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        pctl->eint->base = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(pctl->eint->base))
                return PTR_ERR(pctl->eint->base);

        pctl->eint->irq = irq_of_parse_and_map(np, 0);
        if (!pctl->eint->irq)
                return -EINVAL;

        pctl->eint->dev = &pdev->dev;
        /*
         * If pctl->eint->regs == NULL, it would fall back into using a generic
         * register map in mtk_eint_do_init calls.
         */
        pctl->eint->regs = pctl->devdata->eint_regs;
        pctl->eint->hw = &pctl->devdata->eint_hw;
        pctl->eint->pctl = pctl;
        pctl->eint->gpio_xlate = &mtk_eint_xt;

        return mtk_eint_do_init(pctl->eint);
}

int mtk_pctrl_init(struct platform_device *pdev,
                const struct mtk_pinctrl_devdata *data,
                struct regmap *regmap)
{
        struct pinctrl_pin_desc *pins;
        struct mtk_pinctrl *pctl;
        struct device_node *np = pdev->dev.of_node, *node;
        struct property *prop;
        int ret, i;

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

        platform_set_drvdata(pdev, pctl);

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

        node = of_parse_phandle(np, "mediatek,pctl-regmap", 0);
        if (node) {
                pctl->regmap1 = syscon_node_to_regmap(node);
                if (IS_ERR(pctl->regmap1))
                        return PTR_ERR(pctl->regmap1);
        } else if (regmap) {
                pctl->regmap1  = regmap;
        } else {
                dev_err(&pdev->dev, "Pinctrl node has not register regmap.\n");
                return -EINVAL;
        }

        /* Only 8135 has two base addr, other SoCs have only one. */
        node = of_parse_phandle(np, "mediatek,pctl-regmap", 1);
        if (node) {
                pctl->regmap2 = syscon_node_to_regmap(node);
                if (IS_ERR(pctl->regmap2))
                        return PTR_ERR(pctl->regmap2);
        }

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

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

        for (i = 0; i < pctl->devdata->npins; i++)
                pins[i] = pctl->devdata->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->devdata->npins;
        pctl->pctl_desc.confops = &mtk_pconf_ops;
        pctl->pctl_desc.pctlops = &mtk_pctrl_ops;
        pctl->pctl_desc.pmxops = &mtk_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, "couldn't register pinctrl driver\n");
                return PTR_ERR(pctl->pctl_dev);
        }

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

        *pctl->chip = mtk_gpio_chip;
        pctl->chip->ngpio = pctl->devdata->npins;
        pctl->chip->label = dev_name(&pdev->dev);
        pctl->chip->parent = &pdev->dev;
        pctl->chip->base = -1;

        ret = gpiochip_add_data(pctl->chip, pctl);
        if (ret)
                return -EINVAL;

        /* Register the GPIO to pin mappings. */
        ret = gpiochip_add_pin_range(pctl->chip, dev_name(&pdev->dev),
                        0, 0, pctl->devdata->npins);
        if (ret) {
                ret = -EINVAL;
                goto chip_error;
        }

        ret = mtk_eint_init(pctl, pdev);
        if (ret)
                goto chip_error;

        return 0;

chip_error:
        gpiochip_remove(pctl->chip);
        return ret;
}