/*
 * Marvell 37xx SoC pinctrl driver
 *
 * Copyright (C) 2017 Marvell
 *
 * Gregory CLEMENT <gregory.clement@free-electrons.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2 or later. This program is licensed "as is"
 * without any warranty of any kind, whether express or implied.
 */

#include <linux/mfd/syscon.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinmux.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>

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

#define OUTPUT_EN	0x0
#define OUTPUT_CTL	0x20
#define SELECTION	0x30

#define NB_FUNCS 2
#define GPIO_PER_REG	32

/**
 * struct armada_37xx_pin_group: represents group of pins of a pinmux function.
 * The pins of a pinmux groups are composed of one or two groups of contiguous
 * pins.
 * @name:	Name of the pin group, used to lookup the group.
 * @start_pins:	Index of the first pin of the main range of pins belonging to
 *		the group
 * @npins:	Number of pins included in the first range
 * @reg_mask:	Bit mask matching the group in the selection register
 * @extra_pins:	Index of the first pin of the optional second range of pins
 *		belonging to the group
 * @npins:	Number of pins included in the second optional range
 * @funcs:	A list of pinmux functions that can be selected for this group.
 * @pins:	List of the pins included in the group
 */
struct armada_37xx_pin_group {
	const char	*name;
	unsigned int	start_pin;
	unsigned int	npins;
	u32		reg_mask;
	u32		val[NB_FUNCS];
	unsigned int	extra_pin;
	unsigned int	extra_npins;
	const char	*funcs[NB_FUNCS];
	unsigned int	*pins;
};

struct armada_37xx_pin_data {
	u8				nr_pins;
	char				*name;
	struct armada_37xx_pin_group	*groups;
	int				ngroups;
};

struct armada_37xx_pmx_func {
	const char		*name;
	const char		**groups;
	unsigned int		ngroups;
};

struct armada_37xx_pinctrl {
	struct regmap			*regmap;
	const struct armada_37xx_pin_data	*data;
	struct device			*dev;
	struct pinctrl_desc		pctl;
	struct pinctrl_dev		*pctl_dev;
	struct armada_37xx_pin_group	*groups;
	unsigned int			ngroups;
	struct armada_37xx_pmx_func	*funcs;
	unsigned int			nfuncs;
};

#define PIN_GRP(_name, _start, _nr, _mask, _func1, _func2)	\
	{					\
		.name = _name,			\
		.start_pin = _start,		\
		.npins = _nr,			\
		.reg_mask = _mask,		\
		.val = {0, _mask},		\
		.funcs = {_func1, _func2}	\
	}

#define PIN_GRP_GPIO(_name, _start, _nr, _mask, _func1)	\
	{					\
		.name = _name,			\
		.start_pin = _start,		\
		.npins = _nr,			\
		.reg_mask = _mask,		\
		.val = {0, _mask},		\
		.funcs = {_func1, "gpio"}	\
	}

#define PIN_GRP_GPIO_2(_name, _start, _nr, _mask, _val1, _val2, _func1)   \
	{					\
		.name = _name,			\
		.start_pin = _start,		\
		.npins = _nr,			\
		.reg_mask = _mask,		\
		.val = {_val1, _val2},		\
		.funcs = {_func1, "gpio"}	\
	}

#define PIN_GRP_EXTRA(_name, _start, _nr, _mask, _v1, _v2, _start2, _nr2, \
		      _f1, _f2)				\
	{						\
		.name = _name,				\
		.start_pin = _start,			\
		.npins = _nr,				\
		.reg_mask = _mask,			\
		.val = {_v1, _v2},			\
		.extra_pin = _start2,			\
		.extra_npins = _nr2,			\
		.funcs = {_f1, _f2}			\
	}

static struct armada_37xx_pin_group armada_37xx_nb_groups[] = {
	PIN_GRP_GPIO("jtag", 20, 5, BIT(0), "jtag"),
	PIN_GRP_GPIO("sdio0", 8, 3, BIT(1), "sdio"),
	PIN_GRP_GPIO("emmc_nb", 27, 9, BIT(2), "emmc"),
	PIN_GRP_GPIO("pwm0", 11, 1, BIT(3), "pwm"),
	PIN_GRP_GPIO("pwm1", 12, 1, BIT(4), "pwm"),
	PIN_GRP_GPIO("pwm2", 13, 1, BIT(5), "pwm"),
	PIN_GRP_GPIO("pwm3", 14, 1, BIT(6), "pwm"),
	PIN_GRP_GPIO("pmic1", 17, 1, BIT(7), "pmic"),
	PIN_GRP_GPIO("pmic0", 16, 1, BIT(8), "pmic"),
	PIN_GRP_GPIO("i2c2", 2, 2, BIT(9), "i2c"),
	PIN_GRP_GPIO("i2c1", 0, 2, BIT(10), "i2c"),
	PIN_GRP_GPIO("spi_cs1", 17, 1, BIT(12), "spi"),
	PIN_GRP_GPIO_2("spi_cs2", 18, 1, BIT(13) | BIT(19), 0, BIT(13), "spi"),
	PIN_GRP_GPIO_2("spi_cs3", 19, 1, BIT(14) | BIT(19), 0, BIT(14), "spi"),
	PIN_GRP_GPIO("onewire", 4, 1, BIT(16), "onewire"),
	PIN_GRP_GPIO("uart1", 25, 2, BIT(17), "uart"),
	PIN_GRP_GPIO("spi_quad", 15, 2, BIT(18), "spi"),
	PIN_GRP_EXTRA("uart2", 9, 2, BIT(13) | BIT(14) | BIT(19),
		      BIT(13) | BIT(14), BIT(19), 18, 2, "gpio", "uart"),
	PIN_GRP_GPIO("led0_od", 11, 1, BIT(20), "led"),
	PIN_GRP_GPIO("led1_od", 12, 1, BIT(21), "led"),
	PIN_GRP_GPIO("led2_od", 13, 1, BIT(22), "led"),
	PIN_GRP_GPIO("led3_od", 14, 1, BIT(23), "led"),

};

static struct armada_37xx_pin_group armada_37xx_sb_groups[] = {
	PIN_GRP_GPIO("usb32_drvvbus0", 0, 1, BIT(0), "drvbus"),
	PIN_GRP_GPIO("usb2_drvvbus1", 1, 1, BIT(1), "drvbus"),
	PIN_GRP_GPIO("sdio_sb", 24, 5, BIT(2), "sdio"),
	PIN_GRP_EXTRA("rgmii", 6, 14, BIT(3), 0, BIT(3), 23, 1, "mii", "gpio"),
	PIN_GRP_GPIO("pcie1", 3, 2, BIT(4), "pcie"),
	PIN_GRP_GPIO("ptp", 20, 3, BIT(5), "ptp"),
	PIN_GRP("ptp_clk", 21, 1, BIT(6), "ptp", "mii"),
	PIN_GRP("ptp_trig", 22, 1, BIT(7), "ptp", "mii"),
	PIN_GRP("mii_col", 23, 1, BIT(8), "mii", "mii_err"),
};

const struct armada_37xx_pin_data armada_37xx_pin_nb = {
	.nr_pins = 36,
	.name = "GPIO1",
	.groups = armada_37xx_nb_groups,
	.ngroups = ARRAY_SIZE(armada_37xx_nb_groups),
};

const struct armada_37xx_pin_data armada_37xx_pin_sb = {
	.nr_pins = 29,
	.name = "GPIO2",
	.groups = armada_37xx_sb_groups,
	.ngroups = ARRAY_SIZE(armada_37xx_sb_groups),
};

static int armada_37xx_get_func_reg(struct armada_37xx_pin_group *grp,
				    const char *func)
{
	int f;

	for (f = 0; f < NB_FUNCS; f++)
		if (!strcmp(grp->funcs[f], func))
			return f;

	return -ENOTSUPP;
}

static struct armada_37xx_pin_group *armada_37xx_find_next_grp_by_pin(
	struct armada_37xx_pinctrl *info, int pin, int *grp)
{
	while (*grp < info->ngroups) {
		struct armada_37xx_pin_group *group = &info->groups[*grp];
		int j;

		*grp = *grp + 1;
		for (j = 0; j < (group->npins + group->extra_npins); j++)
			if (group->pins[j] == pin)
				return group;
	}
	return NULL;
}

static int armada_37xx_pin_config_group_get(struct pinctrl_dev *pctldev,
			    unsigned int selector, unsigned long *config)
{
	return -ENOTSUPP;
}

static int armada_37xx_pin_config_group_set(struct pinctrl_dev *pctldev,
			    unsigned int selector, unsigned long *configs,
			    unsigned int num_configs)
{
	return -ENOTSUPP;
}

static struct pinconf_ops armada_37xx_pinconf_ops = {
	.is_generic = true,
	.pin_config_group_get = armada_37xx_pin_config_group_get,
	.pin_config_group_set = armada_37xx_pin_config_group_set,
};

static int armada_37xx_get_groups_count(struct pinctrl_dev *pctldev)
{
	struct armada_37xx_pinctrl *info = pinctrl_dev_get_drvdata(pctldev);

	return info->ngroups;
}

static const char *armada_37xx_get_group_name(struct pinctrl_dev *pctldev,
					      unsigned int group)
{
	struct armada_37xx_pinctrl *info = pinctrl_dev_get_drvdata(pctldev);

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

static int armada_37xx_get_group_pins(struct pinctrl_dev *pctldev,
				      unsigned int selector,
				      const unsigned int **pins,
				      unsigned int *npins)
{
	struct armada_37xx_pinctrl *info = pinctrl_dev_get_drvdata(pctldev);

	if (selector >= info->ngroups)
		return -EINVAL;

	*pins = info->groups[selector].pins;
	*npins = info->groups[selector].npins +
		info->groups[selector].extra_npins;

	return 0;
}

static const struct pinctrl_ops armada_37xx_pctrl_ops = {
	.get_groups_count	= armada_37xx_get_groups_count,
	.get_group_name		= armada_37xx_get_group_name,
	.get_group_pins		= armada_37xx_get_group_pins,
	.dt_node_to_map		= pinconf_generic_dt_node_to_map_group,
	.dt_free_map		= pinctrl_utils_free_map,
};

/*
 * Pinmux_ops handling
 */

static int armada_37xx_pmx_get_funcs_count(struct pinctrl_dev *pctldev)
{
	struct armada_37xx_pinctrl *info = pinctrl_dev_get_drvdata(pctldev);

	return info->nfuncs;
}

static const char *armada_37xx_pmx_get_func_name(struct pinctrl_dev *pctldev,
						 unsigned int selector)
{
	struct armada_37xx_pinctrl *info = pinctrl_dev_get_drvdata(pctldev);

	return info->funcs[selector].name;
}

static int armada_37xx_pmx_get_groups(struct pinctrl_dev *pctldev,
				      unsigned int selector,
				      const char * const **groups,
				      unsigned int * const num_groups)
{
	struct armada_37xx_pinctrl *info = pinctrl_dev_get_drvdata(pctldev);

	*groups = info->funcs[selector].groups;
	*num_groups = info->funcs[selector].ngroups;

	return 0;
}

static int armada_37xx_pmx_set_by_name(struct pinctrl_dev *pctldev,
				       const char *name,
				       struct armada_37xx_pin_group *grp)
{
	struct armada_37xx_pinctrl *info = pinctrl_dev_get_drvdata(pctldev);
	unsigned int reg = SELECTION;
	unsigned int mask = grp->reg_mask;
	int func, val;

	dev_dbg(info->dev, "enable function %s group %s\n",
		name, grp->name);

	func = armada_37xx_get_func_reg(grp, name);

	if (func < 0)
		return func;

	val = grp->val[func];

	regmap_update_bits(info->regmap, reg, mask, val);

	return 0;
}

static int armada_37xx_pmx_set(struct pinctrl_dev *pctldev,
			       unsigned int selector,
			       unsigned int group)
{

	struct armada_37xx_pinctrl *info = pinctrl_dev_get_drvdata(pctldev);
	struct armada_37xx_pin_group *grp = &info->groups[group];
	const char *name = info->funcs[selector].name;

	return armada_37xx_pmx_set_by_name(pctldev, name, grp);
}

static int armada_37xx_pmx_direction_input(struct armada_37xx_pinctrl *info,
					   unsigned int offset)
{
	unsigned int reg = OUTPUT_EN;
	unsigned int mask;

	if (offset >= GPIO_PER_REG) {
		offset -= GPIO_PER_REG;
		reg += sizeof(u32);
	}
	mask = BIT(offset);

	return regmap_update_bits(info->regmap, reg, mask, 0);
}

static int armada_37xx_pmx_direction_output(struct armada_37xx_pinctrl *info,
					    unsigned int offset, int value)
{
	unsigned int reg = OUTPUT_EN;
	unsigned int mask;

	if (offset >= GPIO_PER_REG) {
		offset -= GPIO_PER_REG;
		reg += sizeof(u32);
	}
	mask = BIT(offset);

	return regmap_update_bits(info->regmap, reg, mask, mask);
}

static int armada_37xx_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
					      struct pinctrl_gpio_range *range,
					      unsigned int offset, bool input)
{
	struct armada_37xx_pinctrl *info = pinctrl_dev_get_drvdata(pctldev);

	dev_dbg(info->dev, "gpio_direction for pin %u as %s-%d to %s\n",
		offset, range->name, offset, input ? "input" : "output");

	if (input)
		armada_37xx_pmx_direction_input(info, offset);
	else
		armada_37xx_pmx_direction_output(info, offset, 0);

	return 0;
}

static int armada_37xx_gpio_request_enable(struct pinctrl_dev *pctldev,
					   struct pinctrl_gpio_range *range,
					   unsigned int offset)
{
	struct armada_37xx_pinctrl *info = pinctrl_dev_get_drvdata(pctldev);
	struct armada_37xx_pin_group *group;
	int grp = 0;

	dev_dbg(info->dev, "requesting gpio %d\n", offset);

	while ((group = armada_37xx_find_next_grp_by_pin(info, offset, &grp)))
		armada_37xx_pmx_set_by_name(pctldev, "gpio", group);

	return 0;
}

static const struct pinmux_ops armada_37xx_pmx_ops = {
	.get_functions_count	= armada_37xx_pmx_get_funcs_count,
	.get_function_name	= armada_37xx_pmx_get_func_name,
	.get_function_groups	= armada_37xx_pmx_get_groups,
	.set_mux		= armada_37xx_pmx_set,
	.gpio_request_enable	= armada_37xx_gpio_request_enable,
	.gpio_set_direction	= armada_37xx_pmx_gpio_set_direction,
};

/**
 * armada_37xx_add_function() - Add a new function to the list
 * @funcs: array of function to add the new one
 * @funcsize: size of the remaining space for the function
 * @name: name of the function to add
 *
 * If it is a new function then create it by adding its name else
 * increment the number of group associated to this function.
 */
static int armada_37xx_add_function(struct armada_37xx_pmx_func *funcs,
				    int *funcsize, const char *name)
{
	int i = 0;

	if (*funcsize <= 0)
		return -EOVERFLOW;

	while (funcs->ngroups) {
		/* function already there */
		if (strcmp(funcs->name, name) == 0) {
			funcs->ngroups++;

			return -EEXIST;
		}
		funcs++;
		i++;
	}

	/* append new unique function */
	funcs->name = name;
	funcs->ngroups = 1;
	(*funcsize)--;

	return 0;
}

/**
 * armada_37xx_fill_group() - complete the group array
 * @info: info driver instance
 *
 * Based on the data available from the armada_37xx_pin_group array
 * completes the last member of the struct for each function: the list
 * of the groups associated to this function.
 *
 */
static int armada_37xx_fill_group(struct armada_37xx_pinctrl *info)
{
	int n, num = 0, funcsize = info->data->nr_pins;

	for (n = 0; n < info->ngroups; n++) {
		struct armada_37xx_pin_group *grp = &info->groups[n];
		int i, j, f;

		grp->pins = devm_kzalloc(info->dev,
					 (grp->npins + grp->extra_npins) *
					 sizeof(*grp->pins), GFP_KERNEL);
		if (!grp->pins)
			return -ENOMEM;

		for (i = 0; i < grp->npins; i++)
			grp->pins[i] = grp->start_pin + i;

		for (j = 0; j < grp->extra_npins; j++)
			grp->pins[i+j] = grp->extra_pin + j;

		for (f = 0; f < NB_FUNCS; f++) {
			int ret;
			/* check for unique functions and count groups */
			ret = armada_37xx_add_function(info->funcs, &funcsize,
					    grp->funcs[f]);
			if (ret == -EOVERFLOW)
				dev_err(info->dev,
					"More functions than pins(%d)\n",
					info->data->nr_pins);
			if (ret < 0)
				continue;
			num++;
		}
	}

	info->nfuncs = num;

	return 0;
}

/**
 * armada_37xx_fill_funcs() - complete the funcs array
 * @info: info driver instance
 *
 * Based on the data available from the armada_37xx_pin_group array
 * completes the last two member of the struct for each group:
 * - the list of the pins included in the group
 * - the list of pinmux functions that can be selected for this group
 *
 */
static int armada_37xx_fill_func(struct armada_37xx_pinctrl *info)
{
	struct armada_37xx_pmx_func *funcs = info->funcs;
	int n;

	for (n = 0; n < info->nfuncs; n++) {
		const char *name = funcs[n].name;
		const char **groups;
		int g;

		funcs[n].groups = devm_kzalloc(info->dev, funcs[n].ngroups *
					       sizeof(*(funcs[n].groups)),
					       GFP_KERNEL);
		if (!funcs[n].groups)
			return -ENOMEM;

		groups = funcs[n].groups;

		for (g = 0; g < info->ngroups; g++) {
			struct armada_37xx_pin_group *gp = &info->groups[g];
			int f;

			for (f = 0; f < NB_FUNCS; f++) {
				if (strcmp(gp->funcs[f], name) == 0) {
					*groups = gp->name;
					groups++;
				}
			}
		}
	}
	return 0;
}

static int armada_37xx_pinctrl_register(struct platform_device *pdev,
					struct armada_37xx_pinctrl *info)
{
	const struct armada_37xx_pin_data *pin_data = info->data;
	struct pinctrl_desc *ctrldesc = &info->pctl;
	struct pinctrl_pin_desc *pindesc, *pdesc;
	int pin, ret;

	info->groups = pin_data->groups;
	info->ngroups = pin_data->ngroups;

	ctrldesc->name = "armada_37xx-pinctrl";
	ctrldesc->owner = THIS_MODULE;
	ctrldesc->pctlops = &armada_37xx_pctrl_ops;
	ctrldesc->pmxops = &armada_37xx_pmx_ops;
	ctrldesc->confops = &armada_37xx_pinconf_ops;

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

	ctrldesc->pins = pindesc;
	ctrldesc->npins = pin_data->nr_pins;

	pdesc = pindesc;
	for (pin = 0; pin < pin_data->nr_pins; pin++) {
		pdesc->number = pin;
		pdesc->name = kasprintf(GFP_KERNEL, "%s-%d",
					pin_data->name, pin);
		pdesc++;
	}

	/*
	 * we allocate functions for number of pins and hope there are
	 * fewer unique functions than pins available
	 */
	info->funcs = devm_kzalloc(&pdev->dev, pin_data->nr_pins *
			   sizeof(struct armada_37xx_pmx_func), GFP_KERNEL);
	if (!info->funcs)
		return -ENOMEM;


	ret = armada_37xx_fill_group(info);
	if (ret)
		return ret;

	ret = armada_37xx_fill_func(info);
	if (ret)
		return ret;

	info->pctl_dev = devm_pinctrl_register(&pdev->dev, ctrldesc, info);
	if (IS_ERR(info->pctl_dev)) {
		dev_err(&pdev->dev, "could not register pinctrl driver\n");
		return PTR_ERR(info->pctl_dev);
	}

	return 0;
}

static const struct of_device_id armada_37xx_pinctrl_of_match[] = {
	{
		.compatible = "marvell,armada3710-sb-pinctrl",
		.data = (void *)&armada_37xx_pin_sb,
	},
	{
		.compatible = "marvell,armada3710-nb-pinctrl",
		.data = (void *)&armada_37xx_pin_nb,
	},
	{ },
};

static int __init armada_37xx_pinctrl_probe(struct platform_device *pdev)
{
	struct armada_37xx_pinctrl *info;
	struct device *dev = &pdev->dev;
	struct device_node *np = dev->of_node;
	struct regmap *regmap;
	int ret;

	info = devm_kzalloc(dev, sizeof(struct armada_37xx_pinctrl),
			    GFP_KERNEL);
	if (!info)
		return -ENOMEM;

	info->dev = dev;

	regmap = syscon_node_to_regmap(np);
	if (IS_ERR(regmap)) {
		dev_err(&pdev->dev, "cannot get regmap\n");
		return PTR_ERR(regmap);
	}
	info->regmap = regmap;

	info->data = of_device_get_match_data(dev);

	ret = armada_37xx_pinctrl_register(pdev, info);
	if (ret)
		return ret;

	platform_set_drvdata(pdev, info);

	return 0;
}

static struct platform_driver armada_37xx_pinctrl_driver = {
	.driver = {
		.name = "armada-37xx-pinctrl",
		.of_match_table = armada_37xx_pinctrl_of_match,
	},
};

builtin_platform_driver_probe(armada_37xx_pinctrl_driver,
			      armada_37xx_pinctrl_probe);