drivers/leds/leds-an30259a.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 //
 // Driver for Panasonic AN30259A 3-channel LED driver
 //
 // Copyright (c) 2018 Simon Shields <simon@lineageos.org>
 //
 // Datasheet:
 // https://www.alliedelec.com/m/d/a9d2b3ee87c2d1a535a41dd747b1c247.pdf

 #include <linux/i2c.h>
 #include <linux/leds.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/regmap.h>

 #define AN30259A_MAX_LEDS 3

 #define AN30259A_REG_SRESET 0x00
 #define AN30259A_LED_SRESET BIT(0)

 /* LED power registers */
 #define AN30259A_REG_LED_ON 0x01
 #define AN30259A_LED_EN(x) BIT((x) - 1)
 #define AN30259A_LED_SLOPE(x) BIT(((x) - 1) + 4)

 #define AN30259A_REG_LEDCC(x) (0x03 + ((x) - 1))

 /* slope control registers */
 #define AN30259A_REG_SLOPE(x) (0x06 + ((x) - 1))
 #define AN30259A_LED_SLOPETIME1(x) (x)
 #define AN30259A_LED_SLOPETIME2(x) ((x) << 4)

 #define AN30259A_REG_LEDCNT1(x) (0x09 + (4 * ((x) - 1)))
 #define AN30259A_LED_DUTYMAX(x) ((x) << 4)
 #define AN30259A_LED_DUTYMID(x) (x)

 #define AN30259A_REG_LEDCNT2(x) (0x0A + (4 * ((x) - 1)))
 #define AN30259A_LED_DELAY(x) ((x) << 4)
 #define AN30259A_LED_DUTYMIN(x) (x)

 /* detention time control (length of each slope step) */
 #define AN30259A_REG_LEDCNT3(x) (0x0B + (4 * ((x) - 1)))
 #define AN30259A_LED_DT1(x) (x)
 #define AN30259A_LED_DT2(x) ((x) << 4)

 #define AN30259A_REG_LEDCNT4(x) (0x0C + (4 * ((x) - 1)))
 #define AN30259A_LED_DT3(x) (x)
 #define AN30259A_LED_DT4(x) ((x) << 4)

 #define AN30259A_REG_MAX 0x14

 #define AN30259A_BLINK_MAX_TIME 7500 /* ms */
 #define AN30259A_SLOPE_RESOLUTION 500 /* ms */

 #define AN30259A_NAME "an30259a"

 #define STATE_OFF 0
 #define STATE_KEEP 1
 #define STATE_ON 2

 struct an30259a;

 struct an30259a_led {
 	struct an30259a *chip;
 	struct fwnode_handle *fwnode;
 	struct led_classdev cdev;
 	u32 num;
 	u32 default_state;
 	bool sloping;
 };

 struct an30259a {
 	struct mutex mutex; /* held when writing to registers */
 	struct i2c_client *client;
 	struct an30259a_led leds[AN30259A_MAX_LEDS];
 	struct regmap *regmap;
 	int num_leds;
 };

 static int an30259a_brightness_set(struct led_classdev *cdev,
 				   enum led_brightness brightness)
 {
 	struct an30259a_led *led;
 	int ret;
 	unsigned int led_on;

 	led = container_of(cdev, struct an30259a_led, cdev);
 	mutex_lock(&led->chip->mutex);

 	ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on);
 	if (ret)
 		goto error;

 	switch (brightness) {
 	case LED_OFF:
 		led_on &= ~AN30259A_LED_EN(led->num);
 		led_on &= ~AN30259A_LED_SLOPE(led->num);
 		led->sloping = false;
 		break;
 	default:
 		led_on |= AN30259A_LED_EN(led->num);
 		if (led->sloping)
 			led_on |= AN30259A_LED_SLOPE(led->num);
 		ret = regmap_write(led->chip->regmap,
 				   AN30259A_REG_LEDCNT1(led->num),
 				   AN30259A_LED_DUTYMAX(0xf) |
 				   AN30259A_LED_DUTYMID(0xf));
 		if (ret)
 			goto error;
 		break;
 	}

 	ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on);
 	if (ret)
 		goto error;

 	ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCC(led->num),
 			   brightness);

 error:
 	mutex_unlock(&led->chip->mutex);

 	return ret;
 }

 static int an30259a_blink_set(struct led_classdev *cdev,
 			      unsigned long *delay_off, unsigned long *delay_on)
 {
 	struct an30259a_led *led;
 	int ret, num;
 	unsigned int led_on;
 	unsigned long off = *delay_off, on = *delay_on;

 	led = container_of(cdev, struct an30259a_led, cdev);

 	mutex_lock(&led->chip->mutex);
 	num = led->num;

 	/* slope time can only be a multiple of 500ms. */
 	if (off % AN30259A_SLOPE_RESOLUTION || on % AN30259A_SLOPE_RESOLUTION) {
 		ret = -EINVAL;
 		goto error;
 	}

 	/* up to a maximum of 7500ms. */
 	if (off > AN30259A_BLINK_MAX_TIME || on > AN30259A_BLINK_MAX_TIME) {
 		ret = -EINVAL;
 		goto error;
 	}

 	/* if no blink specified, default to 1 Hz. */
 	if (!off && !on) {
 		*delay_off = off = 500;
 		*delay_on = on = 500;
 	}

 	/* convert into values the HW will understand. */
 	off /= AN30259A_SLOPE_RESOLUTION;
 	on /= AN30259A_SLOPE_RESOLUTION;

 	/* duty min should be zero (=off), delay should be zero. */
 	ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT2(num),
 			   AN30259A_LED_DELAY(0) | AN30259A_LED_DUTYMIN(0));
 	if (ret)
 		goto error;

 	/* reset detention time (no "breathing" effect). */
 	ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT3(num),
 			   AN30259A_LED_DT1(0) | AN30259A_LED_DT2(0));
 	if (ret)
 		goto error;
 	ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT4(num),
 			   AN30259A_LED_DT3(0) | AN30259A_LED_DT4(0));
 	if (ret)
 		goto error;

 	/* slope time controls on/off cycle length. */
 	ret = regmap_write(led->chip->regmap, AN30259A_REG_SLOPE(num),
 			   AN30259A_LED_SLOPETIME1(off) |
 			   AN30259A_LED_SLOPETIME2(on));
 	if (ret)
 		goto error;

 	/* Finally, enable slope mode. */
 	ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on);
 	if (ret)
 		goto error;

 	led_on |= AN30259A_LED_SLOPE(num) | AN30259A_LED_EN(led->num);

 	ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on);

 	if (!ret)
 		led->sloping = true;
 error:
 	mutex_unlock(&led->chip->mutex);

 	return ret;
 }

 static int an30259a_dt_init(struct i2c_client *client,
 			    struct an30259a *chip)
 {
 	struct device_node *np = dev_of_node(&client->dev), *child;
 	int count, ret;
 	int i = 0;
 	const char *str;
 	struct an30259a_led *led;

 	count = of_get_available_child_count(np);
 	if (!count || count > AN30259A_MAX_LEDS)
 		return -EINVAL;

 	for_each_available_child_of_node(np, child) {
 		u32 source;

 		ret = of_property_read_u32(child, "reg", &source);
 		if (ret != 0 || !source || source > AN30259A_MAX_LEDS) {
 			dev_err(&client->dev, "Couldn't read LED address: %d\n",
 				ret);
 			count--;
 			continue;
 		}

 		led = &chip->leds[i];

 		led->num = source;
 		led->chip = chip;
 		led->fwnode = of_fwnode_handle(child);

 		if (!of_property_read_string(child, "default-state", &str)) {
 			if (!strcmp(str, "on"))
 				led->default_state = STATE_ON;
 			else if (!strcmp(str, "keep"))
 				led->default_state = STATE_KEEP;
 			else
 				led->default_state = STATE_OFF;
 		}

 		i++;
 	}

 	if (!count)
 		return -EINVAL;

 	chip->num_leds = i;

 	return 0;
 }

 static const struct regmap_config an30259a_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.max_register = AN30259A_REG_MAX,
 };

 static void an30259a_init_default_state(struct an30259a_led *led)
 {
 	struct an30259a *chip = led->chip;
 	int led_on, err;

 	switch (led->default_state) {
 	case STATE_ON:
 		led->cdev.brightness = LED_FULL;
 		break;
 	case STATE_KEEP:
 		err = regmap_read(chip->regmap, AN30259A_REG_LED_ON, &led_on);
 		if (err)
 			break;

 		if (!(led_on & AN30259A_LED_EN(led->num))) {
 			led->cdev.brightness = LED_OFF;
 			break;
 		}
 		regmap_read(chip->regmap, AN30259A_REG_LEDCC(led->num),
 			    &led->cdev.brightness);
 		break;
 	default:
 		led->cdev.brightness = LED_OFF;
 	}

 	an30259a_brightness_set(&led->cdev, led->cdev.brightness);
 }

 static int an30259a_probe(struct i2c_client *client)
 {
 	struct an30259a *chip;
 	int i, err;

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

 	err = an30259a_dt_init(client, chip);
 	if (err < 0)
 		return err;

 	mutex_init(&chip->mutex);
 	chip->client = client;
 	i2c_set_clientdata(client, chip);

 	chip->regmap = devm_regmap_init_i2c(client, &an30259a_regmap_config);

 	if (IS_ERR(chip->regmap)) {
 		err = PTR_ERR(chip->regmap);
 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
 			err);
 		goto exit;
 	}

 	for (i = 0; i < chip->num_leds; i++) {
 		struct led_init_data init_data = {};

 		an30259a_init_default_state(&chip->leds[i]);
 		chip->leds[i].cdev.brightness_set_blocking =
 			an30259a_brightness_set;
 		chip->leds[i].cdev.blink_set = an30259a_blink_set;

 		init_data.fwnode = chip->leds[i].fwnode;
 		init_data.devicename = AN30259A_NAME;
 		init_data.default_label = ":";

 		err = devm_led_classdev_register_ext(&client->dev,
 						 &chip->leds[i].cdev,
 						 &init_data);
 		if (err < 0)
 			goto exit;
 	}
 	return 0;

 exit:
 	mutex_destroy(&chip->mutex);
 	return err;
 }

 static void an30259a_remove(struct i2c_client *client)
 {
 	struct an30259a *chip = i2c_get_clientdata(client);

 	mutex_destroy(&chip->mutex);
 }

 static const struct of_device_id an30259a_match_table[] = {
 	{ .compatible = "panasonic,an30259a", },
 	{ /* sentinel */ },
 };

 MODULE_DEVICE_TABLE(of, an30259a_match_table);

 static const struct i2c_device_id an30259a_id[] = {
 	{ "an30259a", 0 },
 	{ /* sentinel */ },
 };
 MODULE_DEVICE_TABLE(i2c, an30259a_id);

 static struct i2c_driver an30259a_driver = {
 	.driver = {
 		.name = "leds-an30259a",
 		.of_match_table = of_match_ptr(an30259a_match_table),
 	},
 	.probe_new = an30259a_probe,
 	.remove = an30259a_remove,
 	.id_table = an30259a_id,
 };

 module_i2c_driver(an30259a_driver);

 MODULE_AUTHOR("Simon Shields <simon@lineageos.org>");
 MODULE_DESCRIPTION("AN30259A LED driver");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0+
	//
	// Driver for Panasonic AN30259A 3-channel LED driver
	//
	// Copyright (c) 2018 Simon Shields <simon@lineageos.org>
	//
	// Datasheet:
	// https://www.alliedelec.com/m/d/a9d2b3ee87c2d1a535a41dd747b1c247.pdf

	#include <linux/i2c.h>
	#include <linux/leds.h>
	#include <linux/module.h>
	#include <linux/mutex.h>
	#include <linux/of.h>
	#include <linux/regmap.h>

	#define AN30259A_MAX_LEDS 3

	#define AN30259A_REG_SRESET 0x00
	#define AN30259A_LED_SRESET BIT(0)

	/* LED power registers */
	#define AN30259A_REG_LED_ON 0x01
	#define AN30259A_LED_EN(x) BIT((x) - 1)
	#define AN30259A_LED_SLOPE(x) BIT(((x) - 1) + 4)

	#define AN30259A_REG_LEDCC(x) (0x03 + ((x) - 1))

	/* slope control registers */
	#define AN30259A_REG_SLOPE(x) (0x06 + ((x) - 1))
	#define AN30259A_LED_SLOPETIME1(x) (x)
	#define AN30259A_LED_SLOPETIME2(x) ((x) << 4)

	#define AN30259A_REG_LEDCNT1(x) (0x09 + (4 * ((x) - 1)))
	#define AN30259A_LED_DUTYMAX(x) ((x) << 4)
	#define AN30259A_LED_DUTYMID(x) (x)

	#define AN30259A_REG_LEDCNT2(x) (0x0A + (4 * ((x) - 1)))
	#define AN30259A_LED_DELAY(x) ((x) << 4)
	#define AN30259A_LED_DUTYMIN(x) (x)

	/* detention time control (length of each slope step) */
	#define AN30259A_REG_LEDCNT3(x) (0x0B + (4 * ((x) - 1)))
	#define AN30259A_LED_DT1(x) (x)
	#define AN30259A_LED_DT2(x) ((x) << 4)

	#define AN30259A_REG_LEDCNT4(x) (0x0C + (4 * ((x) - 1)))
	#define AN30259A_LED_DT3(x) (x)
	#define AN30259A_LED_DT4(x) ((x) << 4)

	#define AN30259A_REG_MAX 0x14

	#define AN30259A_BLINK_MAX_TIME 7500 /* ms */
	#define AN30259A_SLOPE_RESOLUTION 500 /* ms */

	#define AN30259A_NAME "an30259a"

	#define STATE_OFF 0
	#define STATE_KEEP 1
	#define STATE_ON 2

	struct an30259a;

	struct an30259a_led {
	struct an30259a *chip;
	struct fwnode_handle *fwnode;
	struct led_classdev cdev;
	u32 num;
	u32 default_state;
	bool sloping;
	};

	struct an30259a {
	struct mutex mutex; /* held when writing to registers */
	struct i2c_client *client;
	struct an30259a_led leds[AN30259A_MAX_LEDS];
	struct regmap *regmap;
	int num_leds;
	};

	static int an30259a_brightness_set(struct led_classdev *cdev,
	enum led_brightness brightness)
	{
	struct an30259a_led *led;
	int ret;
	unsigned int led_on;

	led = container_of(cdev, struct an30259a_led, cdev);
	mutex_lock(&led->chip->mutex);

	ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on);
	if (ret)
	goto error;

	switch (brightness) {
	case LED_OFF:
	led_on &= ~AN30259A_LED_EN(led->num);
	led_on &= ~AN30259A_LED_SLOPE(led->num);
	led->sloping = false;
	break;
	default:
	led_on \|= AN30259A_LED_EN(led->num);
	if (led->sloping)
	led_on \|= AN30259A_LED_SLOPE(led->num);
	ret = regmap_write(led->chip->regmap,
	AN30259A_REG_LEDCNT1(led->num),
	AN30259A_LED_DUTYMAX(0xf) \|
	AN30259A_LED_DUTYMID(0xf));
	if (ret)
	goto error;
	break;
	}

	ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on);
	if (ret)
	goto error;

	ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCC(led->num),
	brightness);

	error:
	mutex_unlock(&led->chip->mutex);

	return ret;
	}

	static int an30259a_blink_set(struct led_classdev *cdev,
	unsigned long delay_off, unsigned long delay_on)
	{
	struct an30259a_led *led;
	int ret, num;
	unsigned int led_on;
	unsigned long off = delay_off, on = delay_on;

	led = container_of(cdev, struct an30259a_led, cdev);

	mutex_lock(&led->chip->mutex);
	num = led->num;

	/* slope time can only be a multiple of 500ms. */
	if (off % AN30259A_SLOPE_RESOLUTION \|\| on % AN30259A_SLOPE_RESOLUTION) {
	ret = -EINVAL;
	goto error;
	}

	/* up to a maximum of 7500ms. */
	if (off > AN30259A_BLINK_MAX_TIME \|\| on > AN30259A_BLINK_MAX_TIME) {
	ret = -EINVAL;
	goto error;
	}

	/* if no blink specified, default to 1 Hz. */
	if (!off && !on) {
	*delay_off = off = 500;
	*delay_on = on = 500;
	}

	/* convert into values the HW will understand. */
	off /= AN30259A_SLOPE_RESOLUTION;
	on /= AN30259A_SLOPE_RESOLUTION;

	/* duty min should be zero (=off), delay should be zero. */
	ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT2(num),
	AN30259A_LED_DELAY(0) \| AN30259A_LED_DUTYMIN(0));
	if (ret)
	goto error;

	/* reset detention time (no "breathing" effect). */
	ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT3(num),
	AN30259A_LED_DT1(0) \| AN30259A_LED_DT2(0));
	if (ret)
	goto error;
	ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT4(num),
	AN30259A_LED_DT3(0) \| AN30259A_LED_DT4(0));
	if (ret)
	goto error;

	/* slope time controls on/off cycle length. */
	ret = regmap_write(led->chip->regmap, AN30259A_REG_SLOPE(num),
	AN30259A_LED_SLOPETIME1(off) \|
	AN30259A_LED_SLOPETIME2(on));
	if (ret)
	goto error;

	/* Finally, enable slope mode. */
	ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on);
	if (ret)
	goto error;

	led_on \|= AN30259A_LED_SLOPE(num) \| AN30259A_LED_EN(led->num);

	ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on);

	if (!ret)
	led->sloping = true;
	error:
	mutex_unlock(&led->chip->mutex);

	return ret;
	}

	static int an30259a_dt_init(struct i2c_client *client,
	struct an30259a *chip)
	{
	struct device_node np = dev_of_node(&client->dev), child;
	int count, ret;
	int i = 0;
	const char *str;
	struct an30259a_led *led;

	count = of_get_available_child_count(np);
	if (!count \|\| count > AN30259A_MAX_LEDS)
	return -EINVAL;

	for_each_available_child_of_node(np, child) {
	u32 source;

	ret = of_property_read_u32(child, "reg", &source);
	if (ret != 0 \|\| !source \|\| source > AN30259A_MAX_LEDS) {
	dev_err(&client->dev, "Couldn't read LED address: %d\n",
	ret);
	count--;
	continue;
	}

	led = &chip->leds[i];

	led->num = source;
	led->chip = chip;
	led->fwnode = of_fwnode_handle(child);

	if (!of_property_read_string(child, "default-state", &str)) {
	if (!strcmp(str, "on"))
	led->default_state = STATE_ON;
	else if (!strcmp(str, "keep"))
	led->default_state = STATE_KEEP;
	else
	led->default_state = STATE_OFF;
	}

	i++;
	}

	if (!count)
	return -EINVAL;

	chip->num_leds = i;

	return 0;
	}

	static const struct regmap_config an30259a_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = AN30259A_REG_MAX,
	};

	static void an30259a_init_default_state(struct an30259a_led *led)
	{
	struct an30259a *chip = led->chip;
	int led_on, err;

	switch (led->default_state) {
	case STATE_ON:
	led->cdev.brightness = LED_FULL;
	break;
	case STATE_KEEP:
	err = regmap_read(chip->regmap, AN30259A_REG_LED_ON, &led_on);
	if (err)
	break;

	if (!(led_on & AN30259A_LED_EN(led->num))) {
	led->cdev.brightness = LED_OFF;
	break;
	}
	regmap_read(chip->regmap, AN30259A_REG_LEDCC(led->num),
	&led->cdev.brightness);
	break;
	default:
	led->cdev.brightness = LED_OFF;
	}

	an30259a_brightness_set(&led->cdev, led->cdev.brightness);
	}

	static int an30259a_probe(struct i2c_client *client)
	{
	struct an30259a *chip;
	int i, err;

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

	err = an30259a_dt_init(client, chip);
	if (err < 0)
	return err;

	mutex_init(&chip->mutex);
	chip->client = client;
	i2c_set_clientdata(client, chip);

	chip->regmap = devm_regmap_init_i2c(client, &an30259a_regmap_config);

	if (IS_ERR(chip->regmap)) {
	err = PTR_ERR(chip->regmap);
	dev_err(&client->dev, "Failed to allocate register map: %d\n",
	err);
	goto exit;
	}

	for (i = 0; i < chip->num_leds; i++) {
	struct led_init_data init_data = {};

	an30259a_init_default_state(&chip->leds[i]);
	chip->leds[i].cdev.brightness_set_blocking =
	an30259a_brightness_set;
	chip->leds[i].cdev.blink_set = an30259a_blink_set;

	init_data.fwnode = chip->leds[i].fwnode;
	init_data.devicename = AN30259A_NAME;
	init_data.default_label = ":";

	err = devm_led_classdev_register_ext(&client->dev,
	&chip->leds[i].cdev,
	&init_data);
	if (err < 0)
	goto exit;
	}
	return 0;

	exit:
	mutex_destroy(&chip->mutex);
	return err;
	}

	static void an30259a_remove(struct i2c_client *client)
	{
	struct an30259a *chip = i2c_get_clientdata(client);

	mutex_destroy(&chip->mutex);
	}

	static const struct of_device_id an30259a_match_table[] = {
	{ .compatible = "panasonic,an30259a", },
	{ /* sentinel */ },
	};

	MODULE_DEVICE_TABLE(of, an30259a_match_table);

	static const struct i2c_device_id an30259a_id[] = {
	{ "an30259a", 0 },
	{ /* sentinel */ },
	};
	MODULE_DEVICE_TABLE(i2c, an30259a_id);

	static struct i2c_driver an30259a_driver = {
	.driver = {
	.name = "leds-an30259a",
	.of_match_table = of_match_ptr(an30259a_match_table),
	},
	.probe_new = an30259a_probe,
	.remove = an30259a_remove,
	.id_table = an30259a_id,
	};

	module_i2c_driver(an30259a_driver);

	MODULE_AUTHOR("Simon Shields <simon@lineageos.org>");
	MODULE_DESCRIPTION("AN30259A LED driver");
	MODULE_LICENSE("GPL v2");