drivers/leds/flash/leds-sy7802.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Silergy SY7802 flash LED driver with an I2C interface
  *
  * Copyright 2024 André Apitzsch <git@apitzsch.eu>
  */

 #include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
 #include <linux/kernel.h>
 #include <linux/led-class-flash.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>

 #define SY7802_MAX_LEDS 2
 #define SY7802_LED_JOINT 2

 #define SY7802_REG_ENABLE		0x10
 #define SY7802_REG_TORCH_BRIGHTNESS	0xa0
 #define SY7802_REG_FLASH_BRIGHTNESS	0xb0
 #define SY7802_REG_FLASH_DURATION	0xc0
 #define SY7802_REG_FLAGS		0xd0
 #define SY7802_REG_CONFIG_1		0xe0
 #define SY7802_REG_CONFIG_2		0xf0
 #define SY7802_REG_VIN_MONITOR		0x80
 #define SY7802_REG_LAST_FLASH		0x81
 #define SY7802_REG_VLED_MONITOR		0x30
 #define SY7802_REG_ADC_DELAY		0x31
 #define SY7802_REG_DEV_ID		0xff

 #define SY7802_MODE_OFF		0
 #define SY7802_MODE_TORCH	2
 #define SY7802_MODE_FLASH	3
 #define SY7802_MODE_MASK	GENMASK(1, 0)

 #define SY7802_LEDS_SHIFT	3
 #define SY7802_LEDS_MASK(_id)	(BIT(_id) << SY7802_LEDS_SHIFT)
 #define SY7802_LEDS_MASK_ALL	(SY7802_LEDS_MASK(0) | SY7802_LEDS_MASK(1))

 #define SY7802_TORCH_CURRENT_SHIFT	3
 #define SY7802_TORCH_CURRENT_MASK(_id) \
 	(GENMASK(2, 0) << (SY7802_TORCH_CURRENT_SHIFT * (_id)))
 #define SY7802_TORCH_CURRENT_MASK_ALL \
 	(SY7802_TORCH_CURRENT_MASK(0) | SY7802_TORCH_CURRENT_MASK(1))

 #define SY7802_FLASH_CURRENT_SHIFT	4
 #define SY7802_FLASH_CURRENT_MASK(_id) \
 	(GENMASK(3, 0) << (SY7802_FLASH_CURRENT_SHIFT * (_id)))
 #define SY7802_FLASH_CURRENT_MASK_ALL \
 	(SY7802_FLASH_CURRENT_MASK(0) | SY7802_FLASH_CURRENT_MASK(1))

 #define SY7802_TIMEOUT_DEFAULT_US	512000U
 #define SY7802_TIMEOUT_MIN_US		32000U
 #define SY7802_TIMEOUT_MAX_US		1024000U
 #define SY7802_TIMEOUT_STEPSIZE_US	32000U

 #define SY7802_TORCH_BRIGHTNESS_MAX 8

 #define SY7802_FLASH_BRIGHTNESS_DEFAULT	14
 #define SY7802_FLASH_BRIGHTNESS_MIN	0
 #define SY7802_FLASH_BRIGHTNESS_MAX	15
 #define SY7802_FLASH_BRIGHTNESS_STEP	1

 #define SY7802_FLAG_TIMEOUT			BIT(0)
 #define SY7802_FLAG_THERMAL_SHUTDOWN		BIT(1)
 #define SY7802_FLAG_LED_FAULT			BIT(2)
 #define SY7802_FLAG_TX1_INTERRUPT		BIT(3)
 #define SY7802_FLAG_TX2_INTERRUPT		BIT(4)
 #define SY7802_FLAG_LED_THERMAL_FAULT		BIT(5)
 #define SY7802_FLAG_FLASH_INPUT_VOLTAGE_LOW	BIT(6)
 #define SY7802_FLAG_INPUT_VOLTAGE_LOW		BIT(7)

 #define SY7802_CHIP_ID	0x51

 static const struct reg_default sy7802_regmap_defs[] = {
 	{ SY7802_REG_ENABLE, SY7802_LEDS_MASK_ALL },
 	{ SY7802_REG_TORCH_BRIGHTNESS, 0x92 },
 	{ SY7802_REG_FLASH_BRIGHTNESS, SY7802_FLASH_BRIGHTNESS_DEFAULT |
 		SY7802_FLASH_BRIGHTNESS_DEFAULT << SY7802_FLASH_CURRENT_SHIFT },
 	{ SY7802_REG_FLASH_DURATION, 0x6f },
 	{ SY7802_REG_FLAGS, 0x0 },
 	{ SY7802_REG_CONFIG_1, 0x68 },
 	{ SY7802_REG_CONFIG_2, 0xf0 },
 };

 struct sy7802_led {
 	struct led_classdev_flash flash;
 	struct sy7802 *chip;
 	u8 led_id;
 };

 struct sy7802 {
 	struct device *dev;
 	struct regmap *regmap;
 	struct mutex mutex;

 	struct gpio_desc *enable_gpio;
 	struct regulator *vin_regulator;

 	unsigned int fled_strobe_used;
 	unsigned int fled_torch_used;
 	unsigned int leds_active;
 	int num_leds;
 	struct sy7802_led leds[] __counted_by(num_leds);
 };

 static int sy7802_torch_brightness_set(struct led_classdev *lcdev, enum led_brightness brightness)
 {
 	struct sy7802_led *led = container_of(lcdev, struct sy7802_led, flash.led_cdev);
 	struct sy7802 *chip = led->chip;
 	u32 fled_torch_used_tmp;
 	u32 led_enable_mask;
 	u32 enable_mask;
 	u32 torch_mask;
 	u32 val;
 	int ret;

 	mutex_lock(&chip->mutex);

 	if (chip->fled_strobe_used) {
 		dev_warn(chip->dev, "Cannot set torch brightness whilst strobe is enabled\n");
 		ret = -EBUSY;
 		goto unlock;
 	}

 	if (brightness)
 		fled_torch_used_tmp = chip->fled_torch_used | BIT(led->led_id);
 	else
 		fled_torch_used_tmp = chip->fled_torch_used & ~BIT(led->led_id);

 	led_enable_mask = led->led_id == SY7802_LED_JOINT ?
 			  SY7802_LEDS_MASK_ALL :
 			  SY7802_LEDS_MASK(led->led_id);

 	val = brightness ? led_enable_mask : SY7802_MODE_OFF;
 	if (fled_torch_used_tmp)
 		val |= SY7802_MODE_TORCH;

 	/* Disable torch to apply brightness */
 	ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, SY7802_MODE_MASK,
 				 SY7802_MODE_OFF);
 	if (ret)
 		goto unlock;

 	torch_mask = led->led_id == SY7802_LED_JOINT ?
 		     SY7802_TORCH_CURRENT_MASK_ALL :
 		     SY7802_TORCH_CURRENT_MASK(led->led_id);

 	/* Register expects brightness between 0 and MAX_BRIGHTNESS - 1 */
 	if (brightness)
 		brightness -= 1;

 	brightness |= (brightness << SY7802_TORCH_CURRENT_SHIFT);

 	ret = regmap_update_bits(chip->regmap, SY7802_REG_TORCH_BRIGHTNESS, torch_mask, brightness);
 	if (ret)
 		goto unlock;

 	enable_mask = SY7802_MODE_MASK | led_enable_mask;
 	ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, enable_mask, val);
 	if (ret)
 		goto unlock;

 	chip->fled_torch_used = fled_torch_used_tmp;

 unlock:
 	mutex_unlock(&chip->mutex);
 	return ret;
 }

 static int sy7802_flash_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness)
 {
 	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
 	struct led_flash_setting *s = &fl_cdev->brightness;
 	u32 val = (brightness - s->min) / s->step;
 	struct sy7802 *chip = led->chip;
 	u32 flash_mask;
 	int ret;

 	val |= (val << SY7802_FLASH_CURRENT_SHIFT);
 	flash_mask = led->led_id == SY7802_LED_JOINT ?
 		     SY7802_FLASH_CURRENT_MASK_ALL :
 		     SY7802_FLASH_CURRENT_MASK(led->led_id);

 	mutex_lock(&chip->mutex);
 	ret = regmap_update_bits(chip->regmap, SY7802_REG_FLASH_BRIGHTNESS, flash_mask, val);
 	mutex_unlock(&chip->mutex);

 	return ret;
 }

 static int sy7802_strobe_set(struct led_classdev_flash *fl_cdev, bool state)
 {
 	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
 	struct sy7802 *chip = led->chip;
 	u32 fled_strobe_used_tmp;
 	u32 led_enable_mask;
 	u32 enable_mask;
 	u32 val;
 	int ret;

 	mutex_lock(&chip->mutex);

 	if (chip->fled_torch_used) {
 		dev_warn(chip->dev, "Cannot set strobe brightness whilst torch is enabled\n");
 		ret = -EBUSY;
 		goto unlock;
 	}

 	if (state)
 		fled_strobe_used_tmp = chip->fled_strobe_used | BIT(led->led_id);
 	else
 		fled_strobe_used_tmp = chip->fled_strobe_used & ~BIT(led->led_id);

 	led_enable_mask = led->led_id == SY7802_LED_JOINT ?
 			  SY7802_LEDS_MASK_ALL :
 			  SY7802_LEDS_MASK(led->led_id);

 	val = state ? led_enable_mask : SY7802_MODE_OFF;
 	if (fled_strobe_used_tmp)
 		val |= SY7802_MODE_FLASH;

 	enable_mask = SY7802_MODE_MASK | led_enable_mask;
 	ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, enable_mask, val);

 	if (ret)
 		goto unlock;

 	chip->fled_strobe_used = fled_strobe_used_tmp;

 unlock:
 	mutex_unlock(&chip->mutex);
 	return ret;
 }

 static int sy7802_strobe_get(struct led_classdev_flash *fl_cdev, bool *state)
 {
 	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
 	struct sy7802 *chip = led->chip;

 	mutex_lock(&chip->mutex);
 	*state = !!(chip->fled_strobe_used & BIT(led->led_id));
 	mutex_unlock(&chip->mutex);

 	return 0;
 }

 static int sy7802_timeout_set(struct led_classdev_flash *fl_cdev, u32 timeout)
 {
 	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
 	struct led_flash_setting *s = &fl_cdev->timeout;
 	u32 val = (timeout - s->min) / s->step;
 	struct sy7802 *chip = led->chip;

 	return regmap_write(chip->regmap, SY7802_REG_FLASH_DURATION, val);
 }

 static int sy7802_fault_get(struct led_classdev_flash *fl_cdev, u32 *fault)
 {
 	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
 	struct sy7802 *chip = led->chip;
 	u32 val, led_faults = 0;
 	int ret;

 	/* NOTE: reading register clears fault status */
 	ret = regmap_read(chip->regmap, SY7802_REG_FLAGS, &val);
 	if (ret)
 		return ret;

 	if (val & (SY7802_FLAG_FLASH_INPUT_VOLTAGE_LOW | SY7802_FLAG_INPUT_VOLTAGE_LOW))
 		led_faults |= LED_FAULT_INPUT_VOLTAGE;

 	if (val & SY7802_FLAG_THERMAL_SHUTDOWN)
 		led_faults |= LED_FAULT_OVER_TEMPERATURE;

 	if (val & SY7802_FLAG_TIMEOUT)
 		led_faults |= LED_FAULT_TIMEOUT;

 	*fault = led_faults;
 	return 0;
 }

 static const struct led_flash_ops sy7802_flash_ops = {
 	.flash_brightness_set = sy7802_flash_brightness_set,
 	.strobe_set = sy7802_strobe_set,
 	.strobe_get = sy7802_strobe_get,
 	.timeout_set = sy7802_timeout_set,
 	.fault_get = sy7802_fault_get,
 };

 static void sy7802_init_flash_brightness(struct led_classdev_flash *fl_cdev)
 {
 	struct led_flash_setting *s;

 	/* Init flash brightness setting */
 	s = &fl_cdev->brightness;
 	s->min = SY7802_FLASH_BRIGHTNESS_MIN;
 	s->max = SY7802_FLASH_BRIGHTNESS_MAX;
 	s->step = SY7802_FLASH_BRIGHTNESS_STEP;
 	s->val = SY7802_FLASH_BRIGHTNESS_DEFAULT;
 }

 static void sy7802_init_flash_timeout(struct led_classdev_flash *fl_cdev)
 {
 	struct led_flash_setting *s;

 	/* Init flash timeout setting */
 	s = &fl_cdev->timeout;
 	s->min = SY7802_TIMEOUT_MIN_US;
 	s->max = SY7802_TIMEOUT_MAX_US;
 	s->step = SY7802_TIMEOUT_STEPSIZE_US;
 	s->val = SY7802_TIMEOUT_DEFAULT_US;
 }

 static int sy7802_led_register(struct device *dev, struct sy7802_led *led,
 			       struct device_node *np)
 {
 	struct led_init_data init_data = {};
 	int ret;

 	init_data.fwnode = of_fwnode_handle(np);

 	ret = devm_led_classdev_flash_register_ext(dev, &led->flash, &init_data);
 	if (ret) {
 		dev_err(dev, "Couldn't register flash %d\n", led->led_id);
 		return ret;
 	}

 	return 0;
 }

 static int sy7802_init_flash_properties(struct device *dev, struct sy7802_led *led,
 					struct device_node *np)
 {
 	struct led_classdev_flash *flash = &led->flash;
 	struct led_classdev *lcdev = &flash->led_cdev;
 	u32 sources[SY7802_MAX_LEDS];
 	int i, num, ret;

 	num = of_property_count_u32_elems(np, "led-sources");
 	if (num < 1) {
 		dev_err(dev, "Not specified or wrong number of led-sources\n");
 		return -EINVAL;
 	}

 	ret = of_property_read_u32_array(np, "led-sources", sources, num);
 	if (ret)
 		return ret;

 	for (i = 0; i < num; i++) {
 		if (sources[i] >= SY7802_MAX_LEDS)
 			return -EINVAL;
 		if (led->chip->leds_active & BIT(sources[i]))
 			return -EINVAL;
 		led->chip->leds_active |= BIT(sources[i]);
 	}

 	/* If both channels are specified in 'led-sources', joint flash output mode is used */
 	led->led_id = num == 2 ? SY7802_LED_JOINT : sources[0];

 	lcdev->max_brightness = SY7802_TORCH_BRIGHTNESS_MAX;
 	lcdev->brightness_set_blocking = sy7802_torch_brightness_set;
 	lcdev->flags |= LED_DEV_CAP_FLASH;

 	flash->ops = &sy7802_flash_ops;

 	sy7802_init_flash_brightness(flash);
 	sy7802_init_flash_timeout(flash);

 	return 0;
 }

 static int sy7802_chip_check(struct sy7802 *chip)
 {
 	struct device *dev = chip->dev;
 	u32 chipid;
 	int ret;

 	ret = regmap_read(chip->regmap, SY7802_REG_DEV_ID, &chipid);
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to read chip ID\n");

 	if (chipid != SY7802_CHIP_ID)
 		return dev_err_probe(dev, -ENODEV, "Unsupported chip detected: %x\n", chipid);

 	return 0;
 }

 static void sy7802_enable(struct sy7802 *chip)
 {
 	gpiod_set_value_cansleep(chip->enable_gpio, 1);
 	usleep_range(200, 300);
 }

 static void sy7802_disable(struct sy7802 *chip)
 {
 	gpiod_set_value_cansleep(chip->enable_gpio, 0);
 }

 static int sy7802_probe_dt(struct sy7802 *chip)
 {
 	struct device_node *np = dev_of_node(chip->dev);
 	int child_num;
 	int ret;

 	regmap_write(chip->regmap, SY7802_REG_ENABLE, SY7802_MODE_OFF);
 	regmap_write(chip->regmap, SY7802_REG_TORCH_BRIGHTNESS, LED_OFF);

 	child_num = 0;
 	for_each_available_child_of_node_scoped(np, child) {
 		struct sy7802_led *led = chip->leds + child_num;

 		led->chip = chip;
 		led->led_id = child_num;

 		ret = sy7802_init_flash_properties(chip->dev, led, child);
 		if (ret)
 			return ret;

 		ret = sy7802_led_register(chip->dev, led, child);
 		if (ret)
 			return ret;

 		child_num++;
 	}
 	return 0;
 }

 static void sy7802_chip_disable_action(void *data)
 {
 	struct sy7802 *chip = data;

 	sy7802_disable(chip);
 }

 static void sy7802_regulator_disable_action(void *data)
 {
 	struct sy7802 *chip = data;

 	regulator_disable(chip->vin_regulator);
 }

 static const struct regmap_config sy7802_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.max_register = 0xff,
 	.cache_type = REGCACHE_MAPLE,
 	.reg_defaults = sy7802_regmap_defs,
 	.num_reg_defaults = ARRAY_SIZE(sy7802_regmap_defs),
 };

 static int sy7802_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
 	struct sy7802 *chip;
 	size_t count;
 	int ret;

 	count = device_get_child_node_count(dev);
 	if (!count || count > SY7802_MAX_LEDS)
 		return dev_err_probe(dev, -EINVAL, "Invalid amount of LED nodes %zu\n", count);

 	chip = devm_kzalloc(dev, struct_size(chip, leds, count), GFP_KERNEL);
 	if (!chip)
 		return -ENOMEM;

 	chip->num_leds = count;

 	chip->dev = dev;
 	i2c_set_clientdata(client, chip);

 	chip->enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
 	ret = PTR_ERR_OR_ZERO(chip->enable_gpio);
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to request enable gpio\n");

 	chip->vin_regulator = devm_regulator_get(dev, "vin");
 	ret = PTR_ERR_OR_ZERO(chip->vin_regulator);
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to request regulator\n");

 	ret = regulator_enable(chip->vin_regulator);
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to enable regulator\n");

 	ret = devm_add_action_or_reset(dev, sy7802_regulator_disable_action, chip);
 	if (ret)
 		return ret;

 	ret = devm_mutex_init(dev, &chip->mutex);
 	if (ret)
 		return ret;

 	mutex_lock(&chip->mutex);

 	chip->regmap = devm_regmap_init_i2c(client, &sy7802_regmap_config);
 	if (IS_ERR(chip->regmap)) {
 		ret = PTR_ERR(chip->regmap);
 		dev_err_probe(dev, ret, "Failed to allocate register map\n");
 		goto error;
 	}

 	ret = sy7802_probe_dt(chip);
 	if (ret < 0)
 		goto error;

 	sy7802_enable(chip);

 	ret = devm_add_action_or_reset(dev, sy7802_chip_disable_action, chip);
 	if (ret)
 		goto error;

 	ret = sy7802_chip_check(chip);

 error:
 	mutex_unlock(&chip->mutex);
 	return ret;
 }

 static const struct of_device_id __maybe_unused sy7802_leds_match[] = {
 	{ .compatible = "silergy,sy7802", },
 	{}
 };
 MODULE_DEVICE_TABLE(of, sy7802_leds_match);

 static struct i2c_driver sy7802_driver = {
 	.driver = {
 		.name = "sy7802",
 		.of_match_table = of_match_ptr(sy7802_leds_match),
 	},
 	.probe = sy7802_probe,
 };
 module_i2c_driver(sy7802_driver);

 MODULE_AUTHOR("André Apitzsch <git@apitzsch.eu>");
 MODULE_DESCRIPTION("Silergy SY7802 flash LED driver");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* Silergy SY7802 flash LED driver with an I2C interface
	*
	* Copyright 2024 André Apitzsch <git@apitzsch.eu>
	*/

	#include <linux/gpio/consumer.h>
	#include <linux/i2c.h>
	#include <linux/kernel.h>
	#include <linux/led-class-flash.h>
	#include <linux/module.h>
	#include <linux/mutex.h>
	#include <linux/regmap.h>
	#include <linux/regulator/consumer.h>

	#define SY7802_MAX_LEDS 2
	#define SY7802_LED_JOINT 2

	#define SY7802_REG_ENABLE 0x10
	#define SY7802_REG_TORCH_BRIGHTNESS 0xa0
	#define SY7802_REG_FLASH_BRIGHTNESS 0xb0
	#define SY7802_REG_FLASH_DURATION 0xc0
	#define SY7802_REG_FLAGS 0xd0
	#define SY7802_REG_CONFIG_1 0xe0
	#define SY7802_REG_CONFIG_2 0xf0
	#define SY7802_REG_VIN_MONITOR 0x80
	#define SY7802_REG_LAST_FLASH 0x81
	#define SY7802_REG_VLED_MONITOR 0x30
	#define SY7802_REG_ADC_DELAY 0x31
	#define SY7802_REG_DEV_ID 0xff

	#define SY7802_MODE_OFF 0
	#define SY7802_MODE_TORCH 2
	#define SY7802_MODE_FLASH 3
	#define SY7802_MODE_MASK GENMASK(1, 0)

	#define SY7802_LEDS_SHIFT 3
	#define SY7802_LEDS_MASK(_id) (BIT(_id) << SY7802_LEDS_SHIFT)
	#define SY7802_LEDS_MASK_ALL (SY7802_LEDS_MASK(0) \| SY7802_LEDS_MASK(1))

	#define SY7802_TORCH_CURRENT_SHIFT 3
	#define SY7802_TORCH_CURRENT_MASK(_id) \
	(GENMASK(2, 0) << (SY7802_TORCH_CURRENT_SHIFT * (_id)))
	#define SY7802_TORCH_CURRENT_MASK_ALL \
	(SY7802_TORCH_CURRENT_MASK(0) \| SY7802_TORCH_CURRENT_MASK(1))

	#define SY7802_FLASH_CURRENT_SHIFT 4
	#define SY7802_FLASH_CURRENT_MASK(_id) \
	(GENMASK(3, 0) << (SY7802_FLASH_CURRENT_SHIFT * (_id)))
	#define SY7802_FLASH_CURRENT_MASK_ALL \
	(SY7802_FLASH_CURRENT_MASK(0) \| SY7802_FLASH_CURRENT_MASK(1))

	#define SY7802_TIMEOUT_DEFAULT_US 512000U
	#define SY7802_TIMEOUT_MIN_US 32000U
	#define SY7802_TIMEOUT_MAX_US 1024000U
	#define SY7802_TIMEOUT_STEPSIZE_US 32000U

	#define SY7802_TORCH_BRIGHTNESS_MAX 8

	#define SY7802_FLASH_BRIGHTNESS_DEFAULT 14
	#define SY7802_FLASH_BRIGHTNESS_MIN 0
	#define SY7802_FLASH_BRIGHTNESS_MAX 15
	#define SY7802_FLASH_BRIGHTNESS_STEP 1

	#define SY7802_FLAG_TIMEOUT BIT(0)
	#define SY7802_FLAG_THERMAL_SHUTDOWN BIT(1)
	#define SY7802_FLAG_LED_FAULT BIT(2)
	#define SY7802_FLAG_TX1_INTERRUPT BIT(3)
	#define SY7802_FLAG_TX2_INTERRUPT BIT(4)
	#define SY7802_FLAG_LED_THERMAL_FAULT BIT(5)
	#define SY7802_FLAG_FLASH_INPUT_VOLTAGE_LOW BIT(6)
	#define SY7802_FLAG_INPUT_VOLTAGE_LOW BIT(7)

	#define SY7802_CHIP_ID 0x51

	static const struct reg_default sy7802_regmap_defs[] = {
	{ SY7802_REG_ENABLE, SY7802_LEDS_MASK_ALL },
	{ SY7802_REG_TORCH_BRIGHTNESS, 0x92 },
	{ SY7802_REG_FLASH_BRIGHTNESS, SY7802_FLASH_BRIGHTNESS_DEFAULT \|
	SY7802_FLASH_BRIGHTNESS_DEFAULT << SY7802_FLASH_CURRENT_SHIFT },
	{ SY7802_REG_FLASH_DURATION, 0x6f },
	{ SY7802_REG_FLAGS, 0x0 },
	{ SY7802_REG_CONFIG_1, 0x68 },
	{ SY7802_REG_CONFIG_2, 0xf0 },
	};

	struct sy7802_led {
	struct led_classdev_flash flash;
	struct sy7802 *chip;
	u8 led_id;
	};

	struct sy7802 {
	struct device *dev;
	struct regmap *regmap;
	struct mutex mutex;

	struct gpio_desc *enable_gpio;
	struct regulator *vin_regulator;

	unsigned int fled_strobe_used;
	unsigned int fled_torch_used;
	unsigned int leds_active;
	int num_leds;
	struct sy7802_led leds[] __counted_by(num_leds);
	};

	static int sy7802_torch_brightness_set(struct led_classdev *lcdev, enum led_brightness brightness)
	{
	struct sy7802_led *led = container_of(lcdev, struct sy7802_led, flash.led_cdev);
	struct sy7802 *chip = led->chip;
	u32 fled_torch_used_tmp;
	u32 led_enable_mask;
	u32 enable_mask;
	u32 torch_mask;
	u32 val;
	int ret;

	mutex_lock(&chip->mutex);

	if (chip->fled_strobe_used) {
	dev_warn(chip->dev, "Cannot set torch brightness whilst strobe is enabled\n");
	ret = -EBUSY;
	goto unlock;
	}

	if (brightness)
	fled_torch_used_tmp = chip->fled_torch_used \| BIT(led->led_id);
	else
	fled_torch_used_tmp = chip->fled_torch_used & ~BIT(led->led_id);

	led_enable_mask = led->led_id == SY7802_LED_JOINT ?
	SY7802_LEDS_MASK_ALL :
	SY7802_LEDS_MASK(led->led_id);

	val = brightness ? led_enable_mask : SY7802_MODE_OFF;
	if (fled_torch_used_tmp)
	val \|= SY7802_MODE_TORCH;

	/* Disable torch to apply brightness */
	ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, SY7802_MODE_MASK,
	SY7802_MODE_OFF);
	if (ret)
	goto unlock;

	torch_mask = led->led_id == SY7802_LED_JOINT ?
	SY7802_TORCH_CURRENT_MASK_ALL :
	SY7802_TORCH_CURRENT_MASK(led->led_id);

	/* Register expects brightness between 0 and MAX_BRIGHTNESS - 1 */
	if (brightness)
	brightness -= 1;

	brightness \|= (brightness << SY7802_TORCH_CURRENT_SHIFT);

	ret = regmap_update_bits(chip->regmap, SY7802_REG_TORCH_BRIGHTNESS, torch_mask, brightness);
	if (ret)
	goto unlock;

	enable_mask = SY7802_MODE_MASK \| led_enable_mask;
	ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, enable_mask, val);
	if (ret)
	goto unlock;

	chip->fled_torch_used = fled_torch_used_tmp;

	unlock:
	mutex_unlock(&chip->mutex);
	return ret;
	}

	static int sy7802_flash_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness)
	{
	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
	struct led_flash_setting *s = &fl_cdev->brightness;
	u32 val = (brightness - s->min) / s->step;
	struct sy7802 *chip = led->chip;
	u32 flash_mask;
	int ret;

	val \|= (val << SY7802_FLASH_CURRENT_SHIFT);
	flash_mask = led->led_id == SY7802_LED_JOINT ?
	SY7802_FLASH_CURRENT_MASK_ALL :
	SY7802_FLASH_CURRENT_MASK(led->led_id);

	mutex_lock(&chip->mutex);
	ret = regmap_update_bits(chip->regmap, SY7802_REG_FLASH_BRIGHTNESS, flash_mask, val);
	mutex_unlock(&chip->mutex);

	return ret;
	}

	static int sy7802_strobe_set(struct led_classdev_flash *fl_cdev, bool state)
	{
	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
	struct sy7802 *chip = led->chip;
	u32 fled_strobe_used_tmp;
	u32 led_enable_mask;
	u32 enable_mask;
	u32 val;
	int ret;

	mutex_lock(&chip->mutex);

	if (chip->fled_torch_used) {
	dev_warn(chip->dev, "Cannot set strobe brightness whilst torch is enabled\n");
	ret = -EBUSY;
	goto unlock;
	}

	if (state)
	fled_strobe_used_tmp = chip->fled_strobe_used \| BIT(led->led_id);
	else
	fled_strobe_used_tmp = chip->fled_strobe_used & ~BIT(led->led_id);

	led_enable_mask = led->led_id == SY7802_LED_JOINT ?
	SY7802_LEDS_MASK_ALL :
	SY7802_LEDS_MASK(led->led_id);

	val = state ? led_enable_mask : SY7802_MODE_OFF;
	if (fled_strobe_used_tmp)
	val \|= SY7802_MODE_FLASH;

	enable_mask = SY7802_MODE_MASK \| led_enable_mask;
	ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, enable_mask, val);

	if (ret)
	goto unlock;

	chip->fled_strobe_used = fled_strobe_used_tmp;

	unlock:
	mutex_unlock(&chip->mutex);
	return ret;
	}

	static int sy7802_strobe_get(struct led_classdev_flash fl_cdev, bool state)
	{
	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
	struct sy7802 *chip = led->chip;

	mutex_lock(&chip->mutex);
	*state = !!(chip->fled_strobe_used & BIT(led->led_id));
	mutex_unlock(&chip->mutex);

	return 0;
	}

	static int sy7802_timeout_set(struct led_classdev_flash *fl_cdev, u32 timeout)
	{
	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
	struct led_flash_setting *s = &fl_cdev->timeout;
	u32 val = (timeout - s->min) / s->step;
	struct sy7802 *chip = led->chip;

	return regmap_write(chip->regmap, SY7802_REG_FLASH_DURATION, val);
	}

	static int sy7802_fault_get(struct led_classdev_flash fl_cdev, u32 fault)
	{
	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
	struct sy7802 *chip = led->chip;
	u32 val, led_faults = 0;
	int ret;

	/* NOTE: reading register clears fault status */
	ret = regmap_read(chip->regmap, SY7802_REG_FLAGS, &val);
	if (ret)
	return ret;

	if (val & (SY7802_FLAG_FLASH_INPUT_VOLTAGE_LOW \| SY7802_FLAG_INPUT_VOLTAGE_LOW))
	led_faults \|= LED_FAULT_INPUT_VOLTAGE;

	if (val & SY7802_FLAG_THERMAL_SHUTDOWN)
	led_faults \|= LED_FAULT_OVER_TEMPERATURE;

	if (val & SY7802_FLAG_TIMEOUT)
	led_faults \|= LED_FAULT_TIMEOUT;

	*fault = led_faults;
	return 0;
	}

	static const struct led_flash_ops sy7802_flash_ops = {
	.flash_brightness_set = sy7802_flash_brightness_set,
	.strobe_set = sy7802_strobe_set,
	.strobe_get = sy7802_strobe_get,
	.timeout_set = sy7802_timeout_set,
	.fault_get = sy7802_fault_get,
	};

	static void sy7802_init_flash_brightness(struct led_classdev_flash *fl_cdev)
	{
	struct led_flash_setting *s;

	/* Init flash brightness setting */
	s = &fl_cdev->brightness;
	s->min = SY7802_FLASH_BRIGHTNESS_MIN;
	s->max = SY7802_FLASH_BRIGHTNESS_MAX;
	s->step = SY7802_FLASH_BRIGHTNESS_STEP;
	s->val = SY7802_FLASH_BRIGHTNESS_DEFAULT;
	}

	static void sy7802_init_flash_timeout(struct led_classdev_flash *fl_cdev)
	{
	struct led_flash_setting *s;

	/* Init flash timeout setting */
	s = &fl_cdev->timeout;
	s->min = SY7802_TIMEOUT_MIN_US;
	s->max = SY7802_TIMEOUT_MAX_US;
	s->step = SY7802_TIMEOUT_STEPSIZE_US;
	s->val = SY7802_TIMEOUT_DEFAULT_US;
	}

	static int sy7802_led_register(struct device dev, struct sy7802_led led,
	struct device_node *np)
	{
	struct led_init_data init_data = {};
	int ret;

	init_data.fwnode = of_fwnode_handle(np);

	ret = devm_led_classdev_flash_register_ext(dev, &led->flash, &init_data);
	if (ret) {
	dev_err(dev, "Couldn't register flash %d\n", led->led_id);
	return ret;
	}

	return 0;
	}

	static int sy7802_init_flash_properties(struct device dev, struct sy7802_led led,
	struct device_node *np)
	{
	struct led_classdev_flash *flash = &led->flash;
	struct led_classdev *lcdev = &flash->led_cdev;
	u32 sources[SY7802_MAX_LEDS];
	int i, num, ret;

	num = of_property_count_u32_elems(np, "led-sources");
	if (num < 1) {
	dev_err(dev, "Not specified or wrong number of led-sources\n");
	return -EINVAL;
	}

	ret = of_property_read_u32_array(np, "led-sources", sources, num);
	if (ret)
	return ret;

	for (i = 0; i < num; i++) {
	if (sources[i] >= SY7802_MAX_LEDS)
	return -EINVAL;
	if (led->chip->leds_active & BIT(sources[i]))
	return -EINVAL;
	led->chip->leds_active \|= BIT(sources[i]);
	}

	/* If both channels are specified in 'led-sources', joint flash output mode is used */
	led->led_id = num == 2 ? SY7802_LED_JOINT : sources[0];

	lcdev->max_brightness = SY7802_TORCH_BRIGHTNESS_MAX;
	lcdev->brightness_set_blocking = sy7802_torch_brightness_set;
	lcdev->flags \|= LED_DEV_CAP_FLASH;

	flash->ops = &sy7802_flash_ops;

	sy7802_init_flash_brightness(flash);
	sy7802_init_flash_timeout(flash);

	return 0;
	}

	static int sy7802_chip_check(struct sy7802 *chip)
	{
	struct device *dev = chip->dev;
	u32 chipid;
	int ret;

	ret = regmap_read(chip->regmap, SY7802_REG_DEV_ID, &chipid);
	if (ret)
	return dev_err_probe(dev, ret, "Failed to read chip ID\n");

	if (chipid != SY7802_CHIP_ID)
	return dev_err_probe(dev, -ENODEV, "Unsupported chip detected: %x\n", chipid);

	return 0;
	}

	static void sy7802_enable(struct sy7802 *chip)
	{
	gpiod_set_value_cansleep(chip->enable_gpio, 1);
	usleep_range(200, 300);
	}

	static void sy7802_disable(struct sy7802 *chip)
	{
	gpiod_set_value_cansleep(chip->enable_gpio, 0);
	}

	static int sy7802_probe_dt(struct sy7802 *chip)
	{
	struct device_node *np = dev_of_node(chip->dev);
	int child_num;
	int ret;

	regmap_write(chip->regmap, SY7802_REG_ENABLE, SY7802_MODE_OFF);
	regmap_write(chip->regmap, SY7802_REG_TORCH_BRIGHTNESS, LED_OFF);

	child_num = 0;
	for_each_available_child_of_node_scoped(np, child) {
	struct sy7802_led *led = chip->leds + child_num;

	led->chip = chip;
	led->led_id = child_num;

	ret = sy7802_init_flash_properties(chip->dev, led, child);
	if (ret)
	return ret;

	ret = sy7802_led_register(chip->dev, led, child);
	if (ret)
	return ret;

	child_num++;
	}
	return 0;
	}

	static void sy7802_chip_disable_action(void *data)
	{
	struct sy7802 *chip = data;

	sy7802_disable(chip);
	}

	static void sy7802_regulator_disable_action(void *data)
	{
	struct sy7802 *chip = data;

	regulator_disable(chip->vin_regulator);
	}

	static const struct regmap_config sy7802_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = 0xff,
	.cache_type = REGCACHE_MAPLE,
	.reg_defaults = sy7802_regmap_defs,
	.num_reg_defaults = ARRAY_SIZE(sy7802_regmap_defs),
	};

	static int sy7802_probe(struct i2c_client *client)
	{
	struct device *dev = &client->dev;
	struct sy7802 *chip;
	size_t count;
	int ret;

	count = device_get_child_node_count(dev);
	if (!count \|\| count > SY7802_MAX_LEDS)
	return dev_err_probe(dev, -EINVAL, "Invalid amount of LED nodes %zu\n", count);

	chip = devm_kzalloc(dev, struct_size(chip, leds, count), GFP_KERNEL);
	if (!chip)
	return -ENOMEM;

	chip->num_leds = count;

	chip->dev = dev;
	i2c_set_clientdata(client, chip);

	chip->enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
	ret = PTR_ERR_OR_ZERO(chip->enable_gpio);
	if (ret)
	return dev_err_probe(dev, ret, "Failed to request enable gpio\n");

	chip->vin_regulator = devm_regulator_get(dev, "vin");
	ret = PTR_ERR_OR_ZERO(chip->vin_regulator);
	if (ret)
	return dev_err_probe(dev, ret, "Failed to request regulator\n");

	ret = regulator_enable(chip->vin_regulator);
	if (ret)
	return dev_err_probe(dev, ret, "Failed to enable regulator\n");

	ret = devm_add_action_or_reset(dev, sy7802_regulator_disable_action, chip);
	if (ret)
	return ret;

	ret = devm_mutex_init(dev, &chip->mutex);
	if (ret)
	return ret;

	mutex_lock(&chip->mutex);

	chip->regmap = devm_regmap_init_i2c(client, &sy7802_regmap_config);
	if (IS_ERR(chip->regmap)) {
	ret = PTR_ERR(chip->regmap);
	dev_err_probe(dev, ret, "Failed to allocate register map\n");
	goto error;
	}

	ret = sy7802_probe_dt(chip);
	if (ret < 0)
	goto error;

	sy7802_enable(chip);

	ret = devm_add_action_or_reset(dev, sy7802_chip_disable_action, chip);
	if (ret)
	goto error;

	ret = sy7802_chip_check(chip);

	error:
	mutex_unlock(&chip->mutex);
	return ret;
	}

	static const struct of_device_id __maybe_unused sy7802_leds_match[] = {
	{ .compatible = "silergy,sy7802", },
	{}
	};
	MODULE_DEVICE_TABLE(of, sy7802_leds_match);

	static struct i2c_driver sy7802_driver = {
	.driver = {
	.name = "sy7802",
	.of_match_table = of_match_ptr(sy7802_leds_match),
	},
	.probe = sy7802_probe,
	};
	module_i2c_driver(sy7802_driver);

	MODULE_AUTHOR("André Apitzsch <git@apitzsch.eu>");
	MODULE_DESCRIPTION("Silergy SY7802 flash LED driver");
	MODULE_LICENSE("GPL");