drivers/regulator/max20086-regulator.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 //
 // max20086-regulator.c - MAX20086-MAX20089 camera power protector driver
 //
 // Copyright (C) 2022 Laurent Pinchart <laurent.pinchart@idesonboard.com>
 // Copyright (C) 2018 Avnet, Inc.

 #include <linux/err.h>
 #include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
 #include <linux/module.h>
 #include <linux/regmap.h>
 #include <linux/regulator/driver.h>
 #include <linux/regulator/machine.h>
 #include <linux/regulator/of_regulator.h>
 #include <linux/slab.h>

 /* Register Offset */
 #define MAX20086_REG_MASK		0x00
 #define MAX20086_REG_CONFIG		0x01
 #define	MAX20086_REG_ID			0x02
 #define	MAX20086_REG_STAT1		0x03
 #define	MAX20086_REG_STAT2_L		0x04
 #define	MAX20086_REG_STAT2_H		0x05
 #define	MAX20086_REG_ADC1		0x06
 #define	MAX20086_REG_ADC2		0x07
 #define	MAX20086_REG_ADC3		0x08
 #define	MAX20086_REG_ADC4		0x09

 /* DEVICE IDs */
 #define MAX20086_DEVICE_ID_MAX20086	0x40
 #define MAX20086_DEVICE_ID_MAX20087	0x20
 #define MAX20086_DEVICE_ID_MAX20088	0x10
 #define MAX20086_DEVICE_ID_MAX20089	0x00
 #define DEVICE_ID_MASK			0xf0

 /* Register bits */
 #define MAX20086_EN_MASK		0x0f
 #define MAX20086_EN_OUT1		0x01
 #define MAX20086_EN_OUT2		0x02
 #define MAX20086_EN_OUT3		0x04
 #define MAX20086_EN_OUT4		0x08
 #define MAX20086_INT_DISABLE_ALL	0x3f

 #define MAX20086_MAX_REGULATORS		4

 struct max20086_chip_info {
 	u8 id;
 	unsigned int num_outputs;
 };

 struct max20086_regulator {
 	struct device_node *of_node;
 	struct regulator_init_data *init_data;
 	const struct regulator_desc *desc;
 	struct regulator_dev *rdev;
 };

 struct max20086 {
 	struct device *dev;
 	struct regmap *regmap;
 	struct gpio_desc *ena_gpiod;

 	const struct max20086_chip_info *info;

 	struct max20086_regulator regulators[MAX20086_MAX_REGULATORS];
 };

 static const struct regulator_ops max20086_buck_ops = {
 	.enable = regulator_enable_regmap,
 	.disable = regulator_disable_regmap,
 	.is_enabled = regulator_is_enabled_regmap,
 };

 #define MAX20086_REGULATOR_DESC(n)		\
 {						\
 	.name = "OUT"#n,			\
 	.supply_name = "in",			\
 	.id = (n) - 1,				\
 	.ops = &max20086_buck_ops,		\
 	.type = REGULATOR_VOLTAGE,		\
 	.owner = THIS_MODULE,			\
 	.enable_reg = MAX20086_REG_CONFIG,	\
 	.enable_mask = 1 << ((n) - 1),		\
 	.enable_val = 1 << ((n) - 1),		\
 	.disable_val = 0,			\
 }

 static const char * const max20086_output_names[] = {
 	"OUT1",
 	"OUT2",
 	"OUT3",
 	"OUT4",
 };

 static const struct regulator_desc max20086_regulators[] = {
 	MAX20086_REGULATOR_DESC(1),
 	MAX20086_REGULATOR_DESC(2),
 	MAX20086_REGULATOR_DESC(3),
 	MAX20086_REGULATOR_DESC(4),
 };

 static int max20086_regulators_register(struct max20086 *chip)
 {
 	unsigned int i;

 	for (i = 0; i < chip->info->num_outputs; i++) {
 		struct max20086_regulator *reg = &chip->regulators[i];
 		struct regulator_config config = { };
 		struct regulator_dev *rdev;

 		config.dev = chip->dev;
 		config.init_data = reg->init_data;
 		config.driver_data = chip;
 		config.of_node = reg->of_node;
 		config.regmap = chip->regmap;
 		config.ena_gpiod = chip->ena_gpiod;

 		rdev = devm_regulator_register(chip->dev, reg->desc, &config);
 		if (IS_ERR(rdev)) {
 			dev_err(chip->dev,
 				"Failed to register regulator output %s\n",
 				reg->desc->name);
 			return PTR_ERR(rdev);
 		}

 		reg->rdev = rdev;
 	}

 	return 0;
 }

 static int max20086_parse_regulators_dt(struct max20086 *chip, bool *boot_on)
 {
 	struct of_regulator_match matches[MAX20086_MAX_REGULATORS] = { };
 	struct device_node *node;
 	unsigned int i;
 	int ret;

 	node = of_get_child_by_name(chip->dev->of_node, "regulators");
 	if (!node) {
 		dev_err(chip->dev, "regulators node not found\n");
 		return -ENODEV;
 	}

 	for (i = 0; i < chip->info->num_outputs; ++i)
 		matches[i].name = max20086_output_names[i];

 	ret = of_regulator_match(chip->dev, node, matches,
 				 chip->info->num_outputs);
 	of_node_put(node);
 	if (ret < 0) {
 		dev_err(chip->dev, "Failed to match regulators\n");
 		return -EINVAL;
 	}

 	*boot_on = false;

 	for (i = 0; i < chip->info->num_outputs; i++) {
 		struct max20086_regulator *reg = &chip->regulators[i];

 		reg->init_data = matches[i].init_data;
 		reg->of_node = matches[i].of_node;
 		reg->desc = &max20086_regulators[i];

 		if (reg->init_data) {
 			if (reg->init_data->constraints.always_on ||
 			    reg->init_data->constraints.boot_on)
 				*boot_on = true;
 		}
 	}

 	return 0;
 }

 static int max20086_detect(struct max20086 *chip)
 {
 	unsigned int data;
 	int ret;

 	ret = regmap_read(chip->regmap, MAX20086_REG_ID, &data);
 	if (ret < 0) {
 		dev_err(chip->dev, "Failed to read DEVICE_ID reg: %d\n", ret);
 		return ret;
 	}

 	if ((data & DEVICE_ID_MASK) != chip->info->id) {
 		dev_err(chip->dev, "Invalid device ID 0x%02x\n", data);
 		return -ENXIO;
 	}

 	return 0;
 }

 static bool max20086_gen_is_writeable_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
 	case MAX20086_REG_MASK:
 	case MAX20086_REG_CONFIG:
 		return true;
 	default:
 		return false;
 	}
 }

 static const struct regmap_config max20086_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.writeable_reg = max20086_gen_is_writeable_reg,
 	.max_register = 0x9,
 	.cache_type = REGCACHE_NONE,
 };

 static int max20086_i2c_probe(struct i2c_client *i2c)
 {
 	struct max20086 *chip;
 	enum gpiod_flags flags;
 	bool boot_on;
 	int ret;

 	chip = devm_kzalloc(&i2c->dev, sizeof(*chip), GFP_KERNEL);
 	if (!chip)
 		return -ENOMEM;

 	chip->dev = &i2c->dev;
 	chip->info = i2c_get_match_data(i2c);

 	i2c_set_clientdata(i2c, chip);

 	chip->regmap = devm_regmap_init_i2c(i2c, &max20086_regmap_config);
 	if (IS_ERR(chip->regmap)) {
 		ret = PTR_ERR(chip->regmap);
 		dev_err(chip->dev, "Failed to allocate register map: %d\n", ret);
 		return ret;
 	}

 	ret = max20086_parse_regulators_dt(chip, &boot_on);
 	if (ret < 0)
 		return ret;

 	ret = max20086_detect(chip);
 	if (ret < 0)
 		return ret;

 	/* Until IRQ support is added, just disable all interrupts. */
 	ret = regmap_update_bits(chip->regmap, MAX20086_REG_MASK,
 				 MAX20086_INT_DISABLE_ALL,
 				 MAX20086_INT_DISABLE_ALL);
 	if (ret < 0) {
 		dev_err(chip->dev, "Failed to disable interrupts: %d\n", ret);
 		return ret;
 	}

 	/*
 	 * Get the enable GPIO. If any of the outputs is marked as being
 	 * enabled at boot, request the GPIO with an initial high state to
 	 * avoid disabling outputs that may have been turned on by the boot
 	 * loader. Otherwise, request it with a low state to enter lower-power
 	 * shutdown.
 	 */
 	flags = boot_on ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
 	chip->ena_gpiod = devm_gpiod_get(chip->dev, "enable", flags);
 	if (IS_ERR(chip->ena_gpiod)) {
 		ret = PTR_ERR(chip->ena_gpiod);
 		dev_err(chip->dev, "Failed to get enable GPIO: %d\n", ret);
 		return ret;
 	}

 	ret = max20086_regulators_register(chip);
 	if (ret < 0) {
 		dev_err(chip->dev, "Failed to register regulators: %d\n", ret);
 		return ret;
 	}

 	return 0;
 }

 static const struct max20086_chip_info max20086_chip_info = {
 	.id = MAX20086_DEVICE_ID_MAX20086,
 	.num_outputs = 4,
 };

 static const struct max20086_chip_info max20087_chip_info = {
 	.id = MAX20086_DEVICE_ID_MAX20087,
 	.num_outputs = 4,
 };

 static const struct max20086_chip_info max20088_chip_info = {
 	.id = MAX20086_DEVICE_ID_MAX20088,
 	.num_outputs = 2,
 };

 static const struct max20086_chip_info max20089_chip_info = {
 	.id = MAX20086_DEVICE_ID_MAX20089,
 	.num_outputs = 2,
 };

 static const struct i2c_device_id max20086_i2c_id[] = {
 	{ "max20086", (kernel_ulong_t)&max20086_chip_info },
 	{ "max20087", (kernel_ulong_t)&max20087_chip_info },
 	{ "max20088", (kernel_ulong_t)&max20088_chip_info },
 	{ "max20089", (kernel_ulong_t)&max20089_chip_info },
 	{ /* Sentinel */ }
 };
 MODULE_DEVICE_TABLE(i2c, max20086_i2c_id);

 static const struct of_device_id max20086_dt_ids[] __maybe_unused = {
 	{ .compatible = "maxim,max20086", .data = &max20086_chip_info },
 	{ .compatible = "maxim,max20087", .data = &max20087_chip_info },
 	{ .compatible = "maxim,max20088", .data = &max20088_chip_info },
 	{ .compatible = "maxim,max20089", .data = &max20089_chip_info },
 	{ /* Sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, max20086_dt_ids);

 static struct i2c_driver max20086_regulator_driver = {
 	.driver = {
 		.name = "max20086",
 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
 		.of_match_table = of_match_ptr(max20086_dt_ids),
 	},
 	.probe = max20086_i2c_probe,
 	.id_table = max20086_i2c_id,
 };

 module_i2c_driver(max20086_regulator_driver);

 MODULE_AUTHOR("Watson Chow <watson.chow@avnet.com>");
 MODULE_DESCRIPTION("MAX20086-MAX20089 Camera Power Protector Driver");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-or-later
	//
	// max20086-regulator.c - MAX20086-MAX20089 camera power protector driver
	//
	// Copyright (C) 2022 Laurent Pinchart <laurent.pinchart@idesonboard.com>
	// Copyright (C) 2018 Avnet, Inc.

	#include <linux/err.h>
	#include <linux/gpio/consumer.h>
	#include <linux/i2c.h>
	#include <linux/module.h>
	#include <linux/regmap.h>
	#include <linux/regulator/driver.h>
	#include <linux/regulator/machine.h>
	#include <linux/regulator/of_regulator.h>
	#include <linux/slab.h>

	/* Register Offset */
	#define MAX20086_REG_MASK 0x00
	#define MAX20086_REG_CONFIG 0x01
	#define MAX20086_REG_ID 0x02
	#define MAX20086_REG_STAT1 0x03
	#define MAX20086_REG_STAT2_L 0x04
	#define MAX20086_REG_STAT2_H 0x05
	#define MAX20086_REG_ADC1 0x06
	#define MAX20086_REG_ADC2 0x07
	#define MAX20086_REG_ADC3 0x08
	#define MAX20086_REG_ADC4 0x09

	/* DEVICE IDs */
	#define MAX20086_DEVICE_ID_MAX20086 0x40
	#define MAX20086_DEVICE_ID_MAX20087 0x20
	#define MAX20086_DEVICE_ID_MAX20088 0x10
	#define MAX20086_DEVICE_ID_MAX20089 0x00
	#define DEVICE_ID_MASK 0xf0

	/* Register bits */
	#define MAX20086_EN_MASK 0x0f
	#define MAX20086_EN_OUT1 0x01
	#define MAX20086_EN_OUT2 0x02
	#define MAX20086_EN_OUT3 0x04
	#define MAX20086_EN_OUT4 0x08
	#define MAX20086_INT_DISABLE_ALL 0x3f

	#define MAX20086_MAX_REGULATORS 4

	struct max20086_chip_info {
	u8 id;
	unsigned int num_outputs;
	};

	struct max20086_regulator {
	struct device_node *of_node;
	struct regulator_init_data *init_data;
	const struct regulator_desc *desc;
	struct regulator_dev *rdev;
	};

	struct max20086 {
	struct device *dev;
	struct regmap *regmap;
	struct gpio_desc *ena_gpiod;

	const struct max20086_chip_info *info;

	struct max20086_regulator regulators[MAX20086_MAX_REGULATORS];
	};

	static const struct regulator_ops max20086_buck_ops = {
	.enable = regulator_enable_regmap,
	.disable = regulator_disable_regmap,
	.is_enabled = regulator_is_enabled_regmap,
	};

	#define MAX20086_REGULATOR_DESC(n) \
	{ \
	.name = "OUT"#n, \
	.supply_name = "in", \
	.id = (n) - 1, \
	.ops = &max20086_buck_ops, \
	.type = REGULATOR_VOLTAGE, \
	.owner = THIS_MODULE, \
	.enable_reg = MAX20086_REG_CONFIG, \
	.enable_mask = 1 << ((n) - 1), \
	.enable_val = 1 << ((n) - 1), \
	.disable_val = 0, \
	}

	static const char * const max20086_output_names[] = {
	"OUT1",
	"OUT2",
	"OUT3",
	"OUT4",
	};

	static const struct regulator_desc max20086_regulators[] = {
	MAX20086_REGULATOR_DESC(1),
	MAX20086_REGULATOR_DESC(2),
	MAX20086_REGULATOR_DESC(3),
	MAX20086_REGULATOR_DESC(4),
	};

	static int max20086_regulators_register(struct max20086 *chip)
	{
	unsigned int i;

	for (i = 0; i < chip->info->num_outputs; i++) {
	struct max20086_regulator *reg = &chip->regulators[i];
	struct regulator_config config = { };
	struct regulator_dev *rdev;

	config.dev = chip->dev;
	config.init_data = reg->init_data;
	config.driver_data = chip;
	config.of_node = reg->of_node;
	config.regmap = chip->regmap;
	config.ena_gpiod = chip->ena_gpiod;

	rdev = devm_regulator_register(chip->dev, reg->desc, &config);
	if (IS_ERR(rdev)) {
	dev_err(chip->dev,
	"Failed to register regulator output %s\n",
	reg->desc->name);
	return PTR_ERR(rdev);
	}

	reg->rdev = rdev;
	}

	return 0;
	}

	static int max20086_parse_regulators_dt(struct max20086 chip, bool boot_on)
	{
	struct of_regulator_match matches[MAX20086_MAX_REGULATORS] = { };
	struct device_node *node;
	unsigned int i;
	int ret;

	node = of_get_child_by_name(chip->dev->of_node, "regulators");
	if (!node) {
	dev_err(chip->dev, "regulators node not found\n");
	return -ENODEV;
	}

	for (i = 0; i < chip->info->num_outputs; ++i)
	matches[i].name = max20086_output_names[i];

	ret = of_regulator_match(chip->dev, node, matches,
	chip->info->num_outputs);
	of_node_put(node);
	if (ret < 0) {
	dev_err(chip->dev, "Failed to match regulators\n");
	return -EINVAL;
	}

	*boot_on = false;

	for (i = 0; i < chip->info->num_outputs; i++) {
	struct max20086_regulator *reg = &chip->regulators[i];

	reg->init_data = matches[i].init_data;
	reg->of_node = matches[i].of_node;
	reg->desc = &max20086_regulators[i];

	if (reg->init_data) {
	if (reg->init_data->constraints.always_on \|\|
	reg->init_data->constraints.boot_on)
	*boot_on = true;
	}
	}

	return 0;
	}

	static int max20086_detect(struct max20086 *chip)
	{
	unsigned int data;
	int ret;

	ret = regmap_read(chip->regmap, MAX20086_REG_ID, &data);
	if (ret < 0) {
	dev_err(chip->dev, "Failed to read DEVICE_ID reg: %d\n", ret);
	return ret;
	}

	if ((data & DEVICE_ID_MASK) != chip->info->id) {
	dev_err(chip->dev, "Invalid device ID 0x%02x\n", data);
	return -ENXIO;
	}

	return 0;
	}

	static bool max20086_gen_is_writeable_reg(struct device *dev, unsigned int reg)
	{
	switch (reg) {
	case MAX20086_REG_MASK:
	case MAX20086_REG_CONFIG:
	return true;
	default:
	return false;
	}
	}

	static const struct regmap_config max20086_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.writeable_reg = max20086_gen_is_writeable_reg,
	.max_register = 0x9,
	.cache_type = REGCACHE_NONE,
	};

	static int max20086_i2c_probe(struct i2c_client *i2c)
	{
	struct max20086 *chip;
	enum gpiod_flags flags;
	bool boot_on;
	int ret;

	chip = devm_kzalloc(&i2c->dev, sizeof(*chip), GFP_KERNEL);
	if (!chip)
	return -ENOMEM;

	chip->dev = &i2c->dev;
	chip->info = i2c_get_match_data(i2c);

	i2c_set_clientdata(i2c, chip);

	chip->regmap = devm_regmap_init_i2c(i2c, &max20086_regmap_config);
	if (IS_ERR(chip->regmap)) {
	ret = PTR_ERR(chip->regmap);
	dev_err(chip->dev, "Failed to allocate register map: %d\n", ret);
	return ret;
	}

	ret = max20086_parse_regulators_dt(chip, &boot_on);
	if (ret < 0)
	return ret;

	ret = max20086_detect(chip);
	if (ret < 0)
	return ret;

	/* Until IRQ support is added, just disable all interrupts. */
	ret = regmap_update_bits(chip->regmap, MAX20086_REG_MASK,
	MAX20086_INT_DISABLE_ALL,
	MAX20086_INT_DISABLE_ALL);
	if (ret < 0) {
	dev_err(chip->dev, "Failed to disable interrupts: %d\n", ret);
	return ret;
	}

	/*
	* Get the enable GPIO. If any of the outputs is marked as being
	* enabled at boot, request the GPIO with an initial high state to
	* avoid disabling outputs that may have been turned on by the boot
	* loader. Otherwise, request it with a low state to enter lower-power
	* shutdown.
	*/
	flags = boot_on ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
	chip->ena_gpiod = devm_gpiod_get(chip->dev, "enable", flags);
	if (IS_ERR(chip->ena_gpiod)) {
	ret = PTR_ERR(chip->ena_gpiod);
	dev_err(chip->dev, "Failed to get enable GPIO: %d\n", ret);
	return ret;
	}

	ret = max20086_regulators_register(chip);
	if (ret < 0) {
	dev_err(chip->dev, "Failed to register regulators: %d\n", ret);
	return ret;
	}

	return 0;
	}

	static const struct max20086_chip_info max20086_chip_info = {
	.id = MAX20086_DEVICE_ID_MAX20086,
	.num_outputs = 4,
	};

	static const struct max20086_chip_info max20087_chip_info = {
	.id = MAX20086_DEVICE_ID_MAX20087,
	.num_outputs = 4,
	};

	static const struct max20086_chip_info max20088_chip_info = {
	.id = MAX20086_DEVICE_ID_MAX20088,
	.num_outputs = 2,
	};

	static const struct max20086_chip_info max20089_chip_info = {
	.id = MAX20086_DEVICE_ID_MAX20089,
	.num_outputs = 2,
	};

	static const struct i2c_device_id max20086_i2c_id[] = {
	{ "max20086", (kernel_ulong_t)&max20086_chip_info },
	{ "max20087", (kernel_ulong_t)&max20087_chip_info },
	{ "max20088", (kernel_ulong_t)&max20088_chip_info },
	{ "max20089", (kernel_ulong_t)&max20089_chip_info },
	{ /* Sentinel */ }
	};
	MODULE_DEVICE_TABLE(i2c, max20086_i2c_id);

	static const struct of_device_id max20086_dt_ids[] __maybe_unused = {
	{ .compatible = "maxim,max20086", .data = &max20086_chip_info },
	{ .compatible = "maxim,max20087", .data = &max20087_chip_info },
	{ .compatible = "maxim,max20088", .data = &max20088_chip_info },
	{ .compatible = "maxim,max20089", .data = &max20089_chip_info },
	{ /* Sentinel */ }
	};
	MODULE_DEVICE_TABLE(of, max20086_dt_ids);

	static struct i2c_driver max20086_regulator_driver = {
	.driver = {
	.name = "max20086",
	.probe_type = PROBE_PREFER_ASYNCHRONOUS,
	.of_match_table = of_match_ptr(max20086_dt_ids),
	},
	.probe = max20086_i2c_probe,
	.id_table = max20086_i2c_id,
	};

	module_i2c_driver(max20086_regulator_driver);

	MODULE_AUTHOR("Watson Chow <watson.chow@avnet.com>");
	MODULE_DESCRIPTION("MAX20086-MAX20089 Camera Power Protector Driver");
	MODULE_LICENSE("GPL");