// SPDX-License-Identifier: GPL-2.0+
/*
 * Driver for BCM6328 GPIO unit (pinctrl + GPIO)
 *
 * Copyright (C) 2021 Álvaro Fernández Rojas <noltari@gmail.com>
 * Copyright (C) 2016 Jonas Gorski <jonas.gorski@gmail.com>
 */

#include <linux/bits.h>
#include <linux/gpio/driver.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/pinctrl/pinmux.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

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

#include "pinctrl-bcm63xx.h"

#define BCM6328_NUM_GPIOS	32

#define BCM6328_MODE_REG	0x18
#define BCM6328_MUX_HI_REG	0x1c
#define BCM6328_MUX_LO_REG	0x20
#define BCM6328_MUX_OTHER_REG	0x24
#define  BCM6328_MUX_MASK	GENMASK(1, 0)

struct bcm6328_pingroup {
	const char *name;
	const unsigned * const pins;
	const unsigned num_pins;
};

struct bcm6328_function {
	const char *name;
	const char * const *groups;
	const unsigned num_groups;

	unsigned mode_val:1;
	unsigned mux_val:2;
};

static const unsigned int bcm6328_mux[] = {
	BCM6328_MUX_LO_REG,
	BCM6328_MUX_HI_REG,
	BCM6328_MUX_OTHER_REG
};

static const struct pinctrl_pin_desc bcm6328_pins[] = {
	PINCTRL_PIN(0, "gpio0"),
	PINCTRL_PIN(1, "gpio1"),
	PINCTRL_PIN(2, "gpio2"),
	PINCTRL_PIN(3, "gpio3"),
	PINCTRL_PIN(4, "gpio4"),
	PINCTRL_PIN(5, "gpio5"),
	PINCTRL_PIN(6, "gpio6"),
	PINCTRL_PIN(7, "gpio7"),
	PINCTRL_PIN(8, "gpio8"),
	PINCTRL_PIN(9, "gpio9"),
	PINCTRL_PIN(10, "gpio10"),
	PINCTRL_PIN(11, "gpio11"),
	PINCTRL_PIN(12, "gpio12"),
	PINCTRL_PIN(13, "gpio13"),
	PINCTRL_PIN(14, "gpio14"),
	PINCTRL_PIN(15, "gpio15"),
	PINCTRL_PIN(16, "gpio16"),
	PINCTRL_PIN(17, "gpio17"),
	PINCTRL_PIN(18, "gpio18"),
	PINCTRL_PIN(19, "gpio19"),
	PINCTRL_PIN(20, "gpio20"),
	PINCTRL_PIN(21, "gpio21"),
	PINCTRL_PIN(22, "gpio22"),
	PINCTRL_PIN(23, "gpio23"),
	PINCTRL_PIN(24, "gpio24"),
	PINCTRL_PIN(25, "gpio25"),
	PINCTRL_PIN(26, "gpio26"),
	PINCTRL_PIN(27, "gpio27"),
	PINCTRL_PIN(28, "gpio28"),
	PINCTRL_PIN(29, "gpio29"),
	PINCTRL_PIN(30, "gpio30"),
	PINCTRL_PIN(31, "gpio31"),

	/*
	 * No idea where they really are; so let's put them according
	 * to their mux offsets.
	 */
	PINCTRL_PIN(36, "hsspi_cs1"),
	PINCTRL_PIN(38, "usb_p2"),
};

static unsigned gpio0_pins[] = { 0 };
static unsigned gpio1_pins[] = { 1 };
static unsigned gpio2_pins[] = { 2 };
static unsigned gpio3_pins[] = { 3 };
static unsigned gpio4_pins[] = { 4 };
static unsigned gpio5_pins[] = { 5 };
static unsigned gpio6_pins[] = { 6 };
static unsigned gpio7_pins[] = { 7 };
static unsigned gpio8_pins[] = { 8 };
static unsigned gpio9_pins[] = { 9 };
static unsigned gpio10_pins[] = { 10 };
static unsigned gpio11_pins[] = { 11 };
static unsigned gpio12_pins[] = { 12 };
static unsigned gpio13_pins[] = { 13 };
static unsigned gpio14_pins[] = { 14 };
static unsigned gpio15_pins[] = { 15 };
static unsigned gpio16_pins[] = { 16 };
static unsigned gpio17_pins[] = { 17 };
static unsigned gpio18_pins[] = { 18 };
static unsigned gpio19_pins[] = { 19 };
static unsigned gpio20_pins[] = { 20 };
static unsigned gpio21_pins[] = { 21 };
static unsigned gpio22_pins[] = { 22 };
static unsigned gpio23_pins[] = { 23 };
static unsigned gpio24_pins[] = { 24 };
static unsigned gpio25_pins[] = { 25 };
static unsigned gpio26_pins[] = { 26 };
static unsigned gpio27_pins[] = { 27 };
static unsigned gpio28_pins[] = { 28 };
static unsigned gpio29_pins[] = { 29 };
static unsigned gpio30_pins[] = { 30 };
static unsigned gpio31_pins[] = { 31 };

static unsigned hsspi_cs1_pins[] = { 36 };
static unsigned usb_port1_pins[] = { 38 };

#define BCM6328_GROUP(n)					\
	{							\
		.name = #n,					\
		.pins = n##_pins,				\
		.num_pins = ARRAY_SIZE(n##_pins),		\
	}

static struct bcm6328_pingroup bcm6328_groups[] = {
	BCM6328_GROUP(gpio0),
	BCM6328_GROUP(gpio1),
	BCM6328_GROUP(gpio2),
	BCM6328_GROUP(gpio3),
	BCM6328_GROUP(gpio4),
	BCM6328_GROUP(gpio5),
	BCM6328_GROUP(gpio6),
	BCM6328_GROUP(gpio7),
	BCM6328_GROUP(gpio8),
	BCM6328_GROUP(gpio9),
	BCM6328_GROUP(gpio10),
	BCM6328_GROUP(gpio11),
	BCM6328_GROUP(gpio12),
	BCM6328_GROUP(gpio13),
	BCM6328_GROUP(gpio14),
	BCM6328_GROUP(gpio15),
	BCM6328_GROUP(gpio16),
	BCM6328_GROUP(gpio17),
	BCM6328_GROUP(gpio18),
	BCM6328_GROUP(gpio19),
	BCM6328_GROUP(gpio20),
	BCM6328_GROUP(gpio21),
	BCM6328_GROUP(gpio22),
	BCM6328_GROUP(gpio23),
	BCM6328_GROUP(gpio24),
	BCM6328_GROUP(gpio25),
	BCM6328_GROUP(gpio26),
	BCM6328_GROUP(gpio27),
	BCM6328_GROUP(gpio28),
	BCM6328_GROUP(gpio29),
	BCM6328_GROUP(gpio30),
	BCM6328_GROUP(gpio31),

	BCM6328_GROUP(hsspi_cs1),
	BCM6328_GROUP(usb_port1),
};

/* GPIO_MODE */
static const char * const led_groups[] = {
	"gpio0",
	"gpio1",
	"gpio2",
	"gpio3",
	"gpio4",
	"gpio5",
	"gpio6",
	"gpio7",
	"gpio8",
	"gpio9",
	"gpio10",
	"gpio11",
	"gpio12",
	"gpio13",
	"gpio14",
	"gpio15",
	"gpio16",
	"gpio17",
	"gpio18",
	"gpio19",
	"gpio20",
	"gpio21",
	"gpio22",
	"gpio23",
};

/* PINMUX_SEL */
static const char * const serial_led_data_groups[] = {
	"gpio6",
};

static const char * const serial_led_clk_groups[] = {
	"gpio7",
};

static const char * const inet_act_led_groups[] = {
	"gpio11",
};

static const char * const pcie_clkreq_groups[] = {
	"gpio16",
};

static const char * const ephy0_act_led_groups[] = {
	"gpio25",
};

static const char * const ephy1_act_led_groups[] = {
	"gpio26",
};

static const char * const ephy2_act_led_groups[] = {
	"gpio27",
};

static const char * const ephy3_act_led_groups[] = {
	"gpio28",
};

static const char * const hsspi_cs1_groups[] = {
	"hsspi_cs1"
};

static const char * const usb_host_port_groups[] = {
	"usb_port1",
};

static const char * const usb_device_port_groups[] = {
	"usb_port1",
};

#define BCM6328_MODE_FUN(n)				\
	{						\
		.name = #n,				\
		.groups = n##_groups,			\
		.num_groups = ARRAY_SIZE(n##_groups),	\
		.mode_val = 1,				\
	}

#define BCM6328_MUX_FUN(n, mux)				\
	{						\
		.name = #n,				\
		.groups = n##_groups,			\
		.num_groups = ARRAY_SIZE(n##_groups),	\
		.mux_val = mux,				\
	}

static const struct bcm6328_function bcm6328_funcs[] = {
	BCM6328_MODE_FUN(led),
	BCM6328_MUX_FUN(serial_led_data, 2),
	BCM6328_MUX_FUN(serial_led_clk, 2),
	BCM6328_MUX_FUN(inet_act_led, 1),
	BCM6328_MUX_FUN(pcie_clkreq, 2),
	BCM6328_MUX_FUN(ephy0_act_led, 1),
	BCM6328_MUX_FUN(ephy1_act_led, 1),
	BCM6328_MUX_FUN(ephy2_act_led, 1),
	BCM6328_MUX_FUN(ephy3_act_led, 1),
	BCM6328_MUX_FUN(hsspi_cs1, 2),
	BCM6328_MUX_FUN(usb_host_port, 1),
	BCM6328_MUX_FUN(usb_device_port, 2),
};

static inline unsigned int bcm6328_mux_off(unsigned int pin)
{
	return bcm6328_mux[pin / 16];
}

static int bcm6328_pinctrl_get_group_count(struct pinctrl_dev *pctldev)
{
	return ARRAY_SIZE(bcm6328_groups);
}

static const char *bcm6328_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
						  unsigned group)
{
	return bcm6328_groups[group].name;
}

static int bcm6328_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
					  unsigned group, const unsigned **pins,
					  unsigned *num_pins)
{
	*pins = bcm6328_groups[group].pins;
	*num_pins = bcm6328_groups[group].num_pins;

	return 0;
}

static int bcm6328_pinctrl_get_func_count(struct pinctrl_dev *pctldev)
{
	return ARRAY_SIZE(bcm6328_funcs);
}

static const char *bcm6328_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
						 unsigned selector)
{
	return bcm6328_funcs[selector].name;
}

static int bcm6328_pinctrl_get_groups(struct pinctrl_dev *pctldev,
				      unsigned selector,
				      const char * const **groups,
				      unsigned * const num_groups)
{
	*groups = bcm6328_funcs[selector].groups;
	*num_groups = bcm6328_funcs[selector].num_groups;

	return 0;
}

static void bcm6328_rmw_mux(struct bcm63xx_pinctrl *pc, unsigned pin,
			    unsigned int mode, unsigned int mux)
{
	if (pin < BCM6328_NUM_GPIOS)
		regmap_update_bits(pc->regs, BCM6328_MODE_REG, BIT(pin),
				   mode ? BIT(pin) : 0);

	regmap_update_bits(pc->regs, bcm6328_mux_off(pin),
			   BCM6328_MUX_MASK << ((pin % 16) * 2),
			   mux << ((pin % 16) * 2));
}

static int bcm6328_pinctrl_set_mux(struct pinctrl_dev *pctldev,
				   unsigned selector, unsigned group)
{
	struct bcm63xx_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev);
	const struct bcm6328_pingroup *pg = &bcm6328_groups[group];
	const struct bcm6328_function *f = &bcm6328_funcs[selector];

	bcm6328_rmw_mux(pc, pg->pins[0], f->mode_val, f->mux_val);

	return 0;
}

static int bcm6328_gpio_request_enable(struct pinctrl_dev *pctldev,
				       struct pinctrl_gpio_range *range,
				       unsigned offset)
{
	struct bcm63xx_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev);

	/* disable all functions using this pin */
	bcm6328_rmw_mux(pc, offset, 0, 0);

	return 0;
}

static const struct pinctrl_ops bcm6328_pctl_ops = {
	.dt_free_map = pinctrl_utils_free_map,
	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
	.get_group_name = bcm6328_pinctrl_get_group_name,
	.get_group_pins = bcm6328_pinctrl_get_group_pins,
	.get_groups_count = bcm6328_pinctrl_get_group_count,
};

static const struct pinmux_ops bcm6328_pmx_ops = {
	.get_function_groups = bcm6328_pinctrl_get_groups,
	.get_function_name = bcm6328_pinctrl_get_func_name,
	.get_functions_count = bcm6328_pinctrl_get_func_count,
	.gpio_request_enable = bcm6328_gpio_request_enable,
	.set_mux = bcm6328_pinctrl_set_mux,
	.strict = true,
};

static const struct bcm63xx_pinctrl_soc bcm6328_soc = {
	.ngpios = BCM6328_NUM_GPIOS,
	.npins = ARRAY_SIZE(bcm6328_pins),
	.pctl_ops = &bcm6328_pctl_ops,
	.pins = bcm6328_pins,
	.pmx_ops = &bcm6328_pmx_ops,
};

static int bcm6328_pinctrl_probe(struct platform_device *pdev)
{
	return bcm63xx_pinctrl_probe(pdev, &bcm6328_soc, NULL);
}

static const struct of_device_id bcm6328_pinctrl_match[] = {
	{ .compatible = "brcm,bcm6328-pinctrl", },
	{ /* sentinel */ }
};

static struct platform_driver bcm6328_pinctrl_driver = {
	.probe = bcm6328_pinctrl_probe,
	.driver = {
		.name = "bcm6328-pinctrl",
		.of_match_table = bcm6328_pinctrl_match,
	},
};

builtin_platform_driver(bcm6328_pinctrl_driver);