drivers/pinctrl/mediatek/pinctrl-paris.c

// SPDX-License-Identifier: GPL-2.0
/*
 * MediaTek Pinctrl Paris Driver, which implement the vendor per-pin
 * bindings for MediaTek SoC.
 *
 * Copyright (C) 2018 MediaTek Inc.
 * Author: Sean Wang <sean.wang@mediatek.com>
 *	   Zhiyong Tao <zhiyong.tao@mediatek.com>
 *	   Hongzhou.Yang <hongzhou.yang@mediatek.com>
 */

#include <linux/gpio/driver.h>
#include <dt-bindings/pinctrl/mt65xx.h>
#include "pinctrl-paris.h"

#define PINCTRL_PINCTRL_DEV	KBUILD_MODNAME

/* Custom pinconf parameters */
#define MTK_PIN_CONFIG_TDSEL	(PIN_CONFIG_END + 1)
#define MTK_PIN_CONFIG_RDSEL	(PIN_CONFIG_END + 2)
#define MTK_PIN_CONFIG_PU_ADV	(PIN_CONFIG_END + 3)
#define MTK_PIN_CONFIG_PD_ADV	(PIN_CONFIG_END + 4)
#define MTK_PIN_CONFIG_DRV_ADV	(PIN_CONFIG_END + 5)

static const struct pinconf_generic_params mtk_custom_bindings[] = {
	{"mediatek,tdsel",	MTK_PIN_CONFIG_TDSEL,		0},
	{"mediatek,rdsel",	MTK_PIN_CONFIG_RDSEL,		0},
	{"mediatek,pull-up-adv", MTK_PIN_CONFIG_PU_ADV,		1},
	{"mediatek,pull-down-adv", MTK_PIN_CONFIG_PD_ADV,	1},
	{"mediatek,drive-strength-adv", MTK_PIN_CONFIG_DRV_ADV,	2},
};

#ifdef CONFIG_DEBUG_FS
static const struct pin_config_item mtk_conf_items[] = {
	PCONFDUMP(MTK_PIN_CONFIG_TDSEL, "tdsel", NULL, true),
	PCONFDUMP(MTK_PIN_CONFIG_RDSEL, "rdsel", NULL, true),
	PCONFDUMP(MTK_PIN_CONFIG_PU_ADV, "pu-adv", NULL, true),
	PCONFDUMP(MTK_PIN_CONFIG_PD_ADV, "pd-adv", NULL, true),
	PCONFDUMP(MTK_PIN_CONFIG_DRV_ADV, "drive-strength-adv", NULL, true),
};
#endif

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

static int mtk_pinmux_gpio_request_enable(struct pinctrl_dev *pctldev,
					  struct pinctrl_gpio_range *range,
					  unsigned int pin)
{
	struct mtk_pinctrl *hw = pinctrl_dev_get_drvdata(pctldev);
	const struct mtk_pin_desc *desc;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[pin];

	return mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_MODE,
				hw->soc->gpio_m);
}

static int mtk_pinmux_gpio_set_direction(struct pinctrl_dev *pctldev,
					 struct pinctrl_gpio_range *range,
					 unsigned int pin, bool input)
{
	struct mtk_pinctrl *hw = pinctrl_dev_get_drvdata(pctldev);
	const struct mtk_pin_desc *desc;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[pin];

	/* hardware would take 0 as input direction */
	return mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DIR, !input);
}

static int mtk_pinconf_get(struct pinctrl_dev *pctldev,
			   unsigned int pin, unsigned long *config)
{
	struct mtk_pinctrl *hw = pinctrl_dev_get_drvdata(pctldev);
	u32 param = pinconf_to_config_param(*config);
	int val, val2, err, reg, ret = 1;
	const struct mtk_pin_desc *desc;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[pin];

	switch (param) {
	case PIN_CONFIG_BIAS_DISABLE:
		if (hw->soc->bias_disable_get) {
			err = hw->soc->bias_disable_get(hw, desc, &ret);
			if (err)
				return err;
		} else {
			return -ENOTSUPP;
		}
		break;
	case PIN_CONFIG_BIAS_PULL_UP:
		if (hw->soc->bias_get) {
			err = hw->soc->bias_get(hw, desc, 1, &ret);
			if (err)
				return err;
		} else {
			return -ENOTSUPP;
		}
		break;
	case PIN_CONFIG_BIAS_PULL_DOWN:
		if (hw->soc->bias_get) {
			err = hw->soc->bias_get(hw, desc, 0, &ret);
			if (err)
				return err;
		} else {
			return -ENOTSUPP;
		}
		break;
	case PIN_CONFIG_SLEW_RATE:
		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_SR, &val);
		if (err)
			return err;

		if (!val)
			return -EINVAL;

		break;
	case PIN_CONFIG_INPUT_ENABLE:
	case PIN_CONFIG_OUTPUT_ENABLE:
		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_DIR, &val);
		if (err)
			return err;

		/* HW takes input mode as zero; output mode as non-zero */
		if ((val && param == PIN_CONFIG_INPUT_ENABLE) ||
		    (!val && param == PIN_CONFIG_OUTPUT_ENABLE))
			return -EINVAL;

		break;
	case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_DIR, &val);
		if (err)
			return err;

		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_SMT, &val2);
		if (err)
			return err;

		if (val || !val2)
			return -EINVAL;

		break;
	case PIN_CONFIG_DRIVE_STRENGTH:
		if (hw->soc->drive_get) {
			err = hw->soc->drive_get(hw, desc, &ret);
			if (err)
				return err;
		} else {
			err = -ENOTSUPP;
		}
		break;
	case MTK_PIN_CONFIG_TDSEL:
	case MTK_PIN_CONFIG_RDSEL:
		reg = (param == MTK_PIN_CONFIG_TDSEL) ?
		       PINCTRL_PIN_REG_TDSEL : PINCTRL_PIN_REG_RDSEL;

		err = mtk_hw_get_value(hw, desc, reg, &val);
		if (err)
			return err;

		ret = val;

		break;
	case MTK_PIN_CONFIG_PU_ADV:
	case MTK_PIN_CONFIG_PD_ADV:
		if (hw->soc->adv_pull_get) {
			bool pullup;

			pullup = param == MTK_PIN_CONFIG_PU_ADV;
			err = hw->soc->adv_pull_get(hw, desc, pullup, &ret);
			if (err)
				return err;
		} else {
			return -ENOTSUPP;
		}
		break;
	case MTK_PIN_CONFIG_DRV_ADV:
		if (hw->soc->adv_drive_get) {
			err = hw->soc->adv_drive_get(hw, desc, &ret);
			if (err)
				return err;
		} else {
			return -ENOTSUPP;
		}
		break;
	default:
		return -ENOTSUPP;
	}

	*config = pinconf_to_config_packed(param, ret);

	return 0;
}

static int mtk_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
			   enum pin_config_param param,
			   enum pin_config_param arg)
{
	struct mtk_pinctrl *hw = pinctrl_dev_get_drvdata(pctldev);
	const struct mtk_pin_desc *desc;
	int err = 0;
	u32 reg;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[pin];

	switch ((u32)param) {
	case PIN_CONFIG_BIAS_DISABLE:
		if (hw->soc->bias_disable_set) {
			err = hw->soc->bias_disable_set(hw, desc);
			if (err)
				return err;
		} else {
			return -ENOTSUPP;
		}
		break;
	case PIN_CONFIG_BIAS_PULL_UP:
		if (hw->soc->bias_set) {
			err = hw->soc->bias_set(hw, desc, 1);
			if (err)
				return err;
		} else {
			return -ENOTSUPP;
		}
		break;
	case PIN_CONFIG_BIAS_PULL_DOWN:
		if (hw->soc->bias_set) {
			err = hw->soc->bias_set(hw, desc, 0);
			if (err)
				return err;
		} else {
			return -ENOTSUPP;
		}
		break;
	case PIN_CONFIG_OUTPUT_ENABLE:
		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_SMT,
				       MTK_DISABLE);
		if (err)
			goto err;

		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DIR,
				       MTK_OUTPUT);
		if (err)
			goto err;
		break;
	case PIN_CONFIG_INPUT_ENABLE:
		if (hw->soc->ies_present) {
			mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_IES,
					 MTK_ENABLE);
		}

		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DIR,
				       MTK_INPUT);
		if (err)
			goto err;
		break;
	case PIN_CONFIG_SLEW_RATE:
		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_SR,
				       arg);
		if (err)
			goto err;

		break;
	case PIN_CONFIG_OUTPUT:
		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DIR,
				       MTK_OUTPUT);
		if (err)
			goto err;

		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DO,
				       arg);
		if (err)
			goto err;
		break;
	case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
		/* arg = 1: Input mode & SMT enable ;
		 * arg = 0: Output mode & SMT disable
		 */
		arg = arg ? 2 : 1;
		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DIR,
				       arg & 1);
		if (err)
			goto err;

		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_SMT,
				       !!(arg & 2));
		if (err)
			goto err;
		break;
	case PIN_CONFIG_DRIVE_STRENGTH:
		if (hw->soc->drive_set) {
			err = hw->soc->drive_set(hw, desc, arg);
			if (err)
				return err;
		} else {
			return -ENOTSUPP;
		}
		break;
	case MTK_PIN_CONFIG_TDSEL:
	case MTK_PIN_CONFIG_RDSEL:
		reg = (param == MTK_PIN_CONFIG_TDSEL) ?
		       PINCTRL_PIN_REG_TDSEL : PINCTRL_PIN_REG_RDSEL;

		err = mtk_hw_set_value(hw, desc, reg, arg);
		if (err)
			goto err;
		break;
	case MTK_PIN_CONFIG_PU_ADV:
	case MTK_PIN_CONFIG_PD_ADV:
		if (hw->soc->adv_pull_set) {
			bool pullup;

			pullup = param == MTK_PIN_CONFIG_PU_ADV;
			err = hw->soc->adv_pull_set(hw, desc, pullup,
						    arg);
			if (err)
				return err;
		} else {
			return -ENOTSUPP;
		}
		break;
	case MTK_PIN_CONFIG_DRV_ADV:
		if (hw->soc->adv_drive_set) {
			err = hw->soc->adv_drive_set(hw, desc, arg);
			if (err)
				return err;
		} else {
			return -ENOTSUPP;
		}
		break;
	default:
		err = -ENOTSUPP;
	}

err:
	return err;
}

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

	for (i = 0; i < hw->soc->ngrps; i++) {
		struct mtk_pinctrl_group *grp = hw->groups + i;

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

	return NULL;
}

static const struct mtk_func_desc *
mtk_pctrl_find_function_by_pin(struct mtk_pinctrl *hw, u32 pin_num, u32 fnum)
{
	const struct mtk_pin_desc *pin = hw->soc->pins + pin_num;
	const struct mtk_func_desc *func = pin->funcs;

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

	return NULL;
}

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

	for (i = 0; i < hw->soc->npins; i++) {
		const struct mtk_pin_desc *pin = hw->soc->pins + i;

		if (pin->number == pin_num) {
			const struct mtk_func_desc *func = pin->funcs;

			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 mtk_pinctrl *hw = pinctrl_dev_get_drvdata(pctldev);
	int num_pins, num_funcs, maps_per_pin, i, err;
	struct mtk_pinctrl_group *grp;
	unsigned int num_configs;
	bool has_config = false;
	unsigned long *configs;
	u32 pinfunc, pin, func;
	struct property *pins;
	unsigned reserve = 0;

	pins = of_find_property(node, "pinmux", NULL);
	if (!pins) {
		dev_err(hw->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 = 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 >= hw->soc->npins ||
		    func >= ARRAY_SIZE(mtk_gpio_functions)) {
			dev_err(hw->dev, "invalid pins value.\n");
			err = -EINVAL;
			goto exit;
		}

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

		err = mtk_pctrl_dt_node_to_map_func(hw, 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 *hw = pinctrl_dev_get_drvdata(pctldev);

	return hw->soc->ngrps;
}

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

	return hw->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 *hw = pinctrl_dev_get_drvdata(pctldev);

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

	return 0;
}

static const struct pinctrl_ops mtk_pctlops = {
	.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 *hw = pinctrl_dev_get_drvdata(pctldev);

	*groups = hw->grp_names;
	*num_groups = hw->soc->ngrps;

	return 0;
}

static int mtk_pmx_set_mux(struct pinctrl_dev *pctldev,
			   unsigned function,
			   unsigned group)
{
	struct mtk_pinctrl *hw = pinctrl_dev_get_drvdata(pctldev);
	struct mtk_pinctrl_group *grp = hw->groups + group;
	const struct mtk_func_desc *desc_func;
	const struct mtk_pin_desc *desc;
	bool ret;

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

	desc_func = mtk_pctrl_find_function_by_pin(hw, grp->pin, function);
	if (!desc_func)
		return -EINVAL;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[grp->pin];
	mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_MODE, desc_func->muxval);

	return 0;
}

static const struct pinmux_ops mtk_pmxops = {
	.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_pinmux_gpio_set_direction,
	.gpio_request_enable	= mtk_pinmux_gpio_request_enable,
};

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

	*config = hw->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 *hw = pinctrl_dev_get_drvdata(pctldev);
	struct mtk_pinctrl_group *grp = &hw->groups[group];
	int i, ret;

	for (i = 0; i < num_configs; i++) {
		ret = mtk_pinconf_set(pctldev, grp->pin,
				      pinconf_to_config_param(configs[i]),
				      pinconf_to_config_argument(configs[i]));
		if (ret < 0)
			return ret;

		grp->config = configs[i];
	}

	return 0;
}

static const struct pinconf_ops mtk_confops = {
	.pin_config_get = mtk_pinconf_get,
	.pin_config_group_get	= mtk_pconf_group_get,
	.pin_config_group_set	= mtk_pconf_group_set,
};

static struct pinctrl_desc mtk_desc = {
	.name = PINCTRL_PINCTRL_DEV,
	.pctlops = &mtk_pctlops,
	.pmxops = &mtk_pmxops,
	.confops = &mtk_confops,
	.owner = THIS_MODULE,
};

static int mtk_gpio_get_direction(struct gpio_chip *chip, unsigned int gpio)
{
	struct mtk_pinctrl *hw = gpiochip_get_data(chip);
	const struct mtk_pin_desc *desc;
	int value, err;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[gpio];

	err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_DIR, &value);
	if (err)
		return err;

	return !value;
}

static int mtk_gpio_get(struct gpio_chip *chip, unsigned int gpio)
{
	struct mtk_pinctrl *hw = gpiochip_get_data(chip);
	const struct mtk_pin_desc *desc;
	int value, err;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[gpio];

	err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_DI, &value);
	if (err)
		return err;

	return !!value;
}

static void mtk_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)
{
	struct mtk_pinctrl *hw = gpiochip_get_data(chip);
	const struct mtk_pin_desc *desc;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[gpio];

	mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DO, !!value);
}

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

static int mtk_gpio_direction_output(struct gpio_chip *chip, unsigned int gpio,
				     int value)
{
	mtk_gpio_set(chip, gpio, value);

	return pinctrl_gpio_direction_output(chip->base + gpio);
}

static int mtk_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
{
	struct mtk_pinctrl *hw = gpiochip_get_data(chip);
	const struct mtk_pin_desc *desc;

	if (!hw->eint)
		return -ENOTSUPP;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[offset];

	if (desc->eint.eint_n == EINT_NA)
		return -ENOTSUPP;

	return mtk_eint_find_irq(hw->eint, desc->eint.eint_n);
}

static int mtk_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
			       unsigned long config)
{
	struct mtk_pinctrl *hw = gpiochip_get_data(chip);
	const struct mtk_pin_desc *desc;
	u32 debounce;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[offset];

	if (!hw->eint ||
	    pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE ||
	    desc->eint.eint_n == EINT_NA)
		return -ENOTSUPP;

	debounce = pinconf_to_config_argument(config);

	return mtk_eint_set_debounce(hw->eint, desc->eint.eint_n, debounce);
}

static int mtk_build_gpiochip(struct mtk_pinctrl *hw, struct device_node *np)
{
	struct gpio_chip *chip = &hw->chip;
	int ret;

	chip->label		= PINCTRL_PINCTRL_DEV;
	chip->parent		= hw->dev;
	chip->request		= gpiochip_generic_request;
	chip->free		= gpiochip_generic_free;
	chip->get_direction	= mtk_gpio_get_direction;
	chip->direction_input	= mtk_gpio_direction_input;
	chip->direction_output	= mtk_gpio_direction_output;
	chip->get		= mtk_gpio_get;
	chip->set		= mtk_gpio_set;
	chip->to_irq		= mtk_gpio_to_irq,
	chip->set_config	= mtk_gpio_set_config,
	chip->base		= -1;
	chip->ngpio		= hw->soc->npins;
	chip->of_node		= np;
	chip->of_gpio_n_cells	= 2;

	ret = gpiochip_add_data(chip, hw);
	if (ret < 0)
		return ret;

	return 0;
}

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

	/* Allocate groups */
	hw->groups = devm_kmalloc_array(&pdev->dev, hw->soc->ngrps,
					sizeof(*hw->groups), GFP_KERNEL);
	if (!hw->groups)
		return -ENOMEM;

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

	for (i = 0; i < hw->soc->npins; i++) {
		const struct mtk_pin_desc *pin = hw->soc->pins + i;
		struct mtk_pinctrl_group *group = hw->groups + i;

		group->name = pin->name;
		group->pin = pin->number;

		hw->grp_names[i] = pin->name;
	}

	return 0;
}

int mtk_paris_pinctrl_probe(struct platform_device *pdev,
			    const struct mtk_pin_soc *soc)
{
	struct pinctrl_pin_desc *pins;
	struct mtk_pinctrl *hw;
	struct resource *res;
	int err, i;

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

	platform_set_drvdata(pdev, hw);
	hw->soc = soc;
	hw->dev = &pdev->dev;

	if (!hw->soc->nbase_names) {
		dev_err(&pdev->dev,
			"SoC should be assigned at least one register base\n");
		return -EINVAL;
	}

	hw->base = devm_kmalloc_array(&pdev->dev, hw->soc->nbase_names,
				      sizeof(*hw->base), GFP_KERNEL);
	if (IS_ERR(hw->base))
		return PTR_ERR(hw->base);

	for (i = 0; i < hw->soc->nbase_names; i++) {
		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
						   hw->soc->base_names[i]);
		if (!res) {
			dev_err(&pdev->dev, "missing IO resource\n");
			return -ENXIO;
		}

		hw->base[i] = devm_ioremap_resource(&pdev->dev, res);
		if (IS_ERR(hw->base[i]))
			return PTR_ERR(hw->base[i]);
	}

	hw->nbase = hw->soc->nbase_names;

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

	/* Copy from internal struct mtk_pin_desc to register to the core */
	pins = devm_kmalloc_array(&pdev->dev, hw->soc->npins, sizeof(*pins),
				  GFP_KERNEL);
	if (IS_ERR(pins))
		return PTR_ERR(pins);

	for (i = 0; i < hw->soc->npins; i++) {
		pins[i].number = hw->soc->pins[i].number;
		pins[i].name = hw->soc->pins[i].name;
	}

	/* Setup pins descriptions per SoC types */
	mtk_desc.pins = (const struct pinctrl_pin_desc *)pins;
	mtk_desc.npins = hw->soc->npins;
	mtk_desc.num_custom_params = ARRAY_SIZE(mtk_custom_bindings);
	mtk_desc.custom_params = mtk_custom_bindings;
#ifdef CONFIG_DEBUG_FS
	mtk_desc.custom_conf_items = mtk_conf_items;
#endif

	err = devm_pinctrl_register_and_init(&pdev->dev, &mtk_desc, hw,
					     &hw->pctrl);
	if (err)
		return err;

	err = pinctrl_enable(hw->pctrl);
	if (err)
		return err;

	err = mtk_build_eint(hw, pdev);
	if (err)
		dev_warn(&pdev->dev,
			 "Failed to add EINT, but pinctrl still can work\n");

	/* Build gpiochip should be after pinctrl_enable is done */
	err = mtk_build_gpiochip(hw, pdev->dev.of_node);
	if (err) {
		dev_err(&pdev->dev, "Failed to add gpio_chip\n");
		return err;
	}

	platform_set_drvdata(pdev, hw);

	return 0;
}