Commit 0ebdb721 authored by André Apitzsch's avatar André Apitzsch Committed by Lee Jones
Browse files

leds: Add ktd202x driver 



This commit adds support for Kinetic KTD2026/7 RGB/White LED driver.

Signed-off-by: default avatarAndré Apitzsch <git@apitzsch.eu>
Link: https://lore.kernel.org/r/20231002-ktd202x-v6-2-26be8eefeb88@apitzsch.eu


Signed-off-by: default avatarLee Jones <lee@kernel.org>
parent 000b1eab

drivers/leds/rgb/Kconfig

+13 −0
Original line number Diff line number Diff line
@@ -14,6 +14,19 @@ config LEDS_GROUP_MULTICOLOR 
	  To compile this driver as a module, choose M here: the module

	  will be called leds-group-multicolor.



config LEDS_KTD202X

	tristate "LED support for KTD202x Chips"

	depends on I2C

	depends on OF

	select REGMAP_I2C

	help

	  This option enables support for the Kinetic KTD2026/KTD2027

	  RGB/White LED driver found in different BQ mobile phones.

	  It is a 3 or 4 channel LED driver programmed via an I2C interface.



	  To compile this driver as a module, choose M here: the module

	  will be called leds-ktd202x.



config LEDS_PWM_MULTICOLOR

	tristate "PWM driven multi-color LED Support"

	depends on PWM

drivers/leds/rgb/Makefile

+1 −0
Original line number Diff line number Diff line 
# SPDX-License-Identifier: GPL-2.0



obj-$(CONFIG_LEDS_GROUP_MULTICOLOR)	+= leds-group-multicolor.o

obj-$(CONFIG_LEDS_KTD202X)		+= leds-ktd202x.o

obj-$(CONFIG_LEDS_PWM_MULTICOLOR)	+= leds-pwm-multicolor.o

obj-$(CONFIG_LEDS_QCOM_LPG)		+= leds-qcom-lpg.o

obj-$(CONFIG_LEDS_MT6370_RGB)		+= leds-mt6370-rgb.o

drivers/leds/rgb/leds-ktd202x.c

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+625 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * Kinetic KTD2026/7 RGB/White LED driver with I2C interface

 *

 * Copyright 2023 André Apitzsch <git@apitzsch.eu>

 *

 * Datasheet: https://www.kinet-ic.com/uploads/KTD2026-7-04h.pdf

 */



#include <linux/i2c.h>

#include <linux/led-class-multicolor.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/of.h>

#include <linux/of_device.h>

#include <linux/regmap.h>

#include <linux/regulator/consumer.h>



#define KTD2026_NUM_LEDS 3

#define KTD2027_NUM_LEDS 4

#define KTD202X_MAX_LEDS 4



/* Register bank */

#define KTD202X_REG_RESET_CONTROL	0x00

#define KTD202X_REG_FLASH_PERIOD	0x01

#define KTD202X_REG_PWM1_TIMER		0x02

#define KTD202X_REG_PWM2_TIMER		0x03

#define KTD202X_REG_CHANNEL_CTRL	0x04

#define KTD202X_REG_TRISE_FALL		0x05

#define KTD202X_REG_LED_IOUT(x)		(0x06 + (x))



/* Register 0 */

#define KTD202X_TIMER_SLOT_CONTROL_TSLOT1	0x00

#define KTD202X_TIMER_SLOT_CONTROL_TSLOT2	0x01

#define KTD202X_TIMER_SLOT_CONTROL_TSLOT3	0x02

#define KTD202X_TIMER_SLOT_CONTROL_TSLOT4	0x03

#define KTD202X_RSTR_RESET			0x07



#define KTD202X_ENABLE_CTRL_WAKE	0x00 /* SCL High & SDA High */

#define KTD202X_ENABLE_CTRL_SLEEP	0x08 /* SCL High & SDA Toggling */



#define KTD202X_TRISE_FALL_SCALE_NORMAL		0x00

#define KTD202X_TRISE_FALL_SCALE_SLOW_X2	0x20

#define KTD202X_TRISE_FALL_SCALE_SLOW_X4	0x40

#define KTD202X_TRISE_FALL_SCALE_FAST_X8	0x60



/* Register 1 */

#define KTD202X_FLASH_PERIOD_256_MS_LOG_RAMP	0x00



/* Register 2-3 */

#define KTD202X_FLASH_ON_TIME_0_4_PERCENT	0x01



/* Register 4 */

#define KTD202X_CHANNEL_CTRL_MASK(x) (BIT(2 * (x)) | BIT(2 * (x) + 1))

#define KTD202X_CHANNEL_CTRL_OFF 0x00

#define KTD202X_CHANNEL_CTRL_ON(x) BIT(2 * (x))

#define KTD202X_CHANNEL_CTRL_PWM1(x) BIT(2 * (x) + 1)

#define KTD202X_CHANNEL_CTRL_PWM2(x) (BIT(2 * (x)) | BIT(2 * (x) + 1))



/* Register 5 */

#define KTD202X_RAMP_TIMES_2_MS			0x00



/* Register 6-9 */

#define KTD202X_LED_CURRENT_10_mA		0x4f



#define KTD202X_FLASH_PERIOD_MIN_MS 256

#define KTD202X_FLASH_PERIOD_STEP_MS 128

#define KTD202X_FLASH_PERIOD_MAX_STEPS 126

#define KTD202X_FLASH_ON_MAX 256



#define KTD202X_MAX_BRIGHTNESS 192



static const struct reg_default ktd202x_reg_defaults[] = {

	{ KTD202X_REG_RESET_CONTROL, KTD202X_TIMER_SLOT_CONTROL_TSLOT1 |

		KTD202X_ENABLE_CTRL_WAKE | KTD202X_TRISE_FALL_SCALE_NORMAL },

	{ KTD202X_REG_FLASH_PERIOD, KTD202X_FLASH_PERIOD_256_MS_LOG_RAMP },

	{ KTD202X_REG_PWM1_TIMER, KTD202X_FLASH_ON_TIME_0_4_PERCENT },

	{ KTD202X_REG_PWM2_TIMER, KTD202X_FLASH_ON_TIME_0_4_PERCENT },

	{ KTD202X_REG_CHANNEL_CTRL, KTD202X_CHANNEL_CTRL_OFF },

	{ KTD202X_REG_TRISE_FALL, KTD202X_RAMP_TIMES_2_MS },

	{ KTD202X_REG_LED_IOUT(0), KTD202X_LED_CURRENT_10_mA },

	{ KTD202X_REG_LED_IOUT(1), KTD202X_LED_CURRENT_10_mA },

	{ KTD202X_REG_LED_IOUT(2), KTD202X_LED_CURRENT_10_mA },

	{ KTD202X_REG_LED_IOUT(3), KTD202X_LED_CURRENT_10_mA },

};



struct ktd202x_led {

	struct ktd202x *chip;

	union {

		struct led_classdev cdev;

		struct led_classdev_mc mcdev;

	};

	u32 index;

};



struct ktd202x {

	struct mutex mutex;

	struct regulator_bulk_data regulators[2];

	struct device *dev;

	struct regmap *regmap;

	bool enabled;

	int num_leds;

	struct ktd202x_led leds[] __counted_by(num_leds);

};



static int ktd202x_chip_disable(struct ktd202x *chip)

{

	int ret;



	if (!chip->enabled)

		return 0;



	regmap_write(chip->regmap, KTD202X_REG_RESET_CONTROL, KTD202X_ENABLE_CTRL_SLEEP);



	ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators), chip->regulators);

	if (ret) {

		dev_err(chip->dev, "Failed to disable regulators: %d\n", ret);

		return ret;

	}



	chip->enabled = false;

	return 0;

}



static int ktd202x_chip_enable(struct ktd202x *chip)

{

	int ret;



	if (chip->enabled)

		return 0;



	ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators), chip->regulators);

	if (ret) {

		dev_err(chip->dev, "Failed to enable regulators: %d\n", ret);

		return ret;

	}

	chip->enabled = true;



	ret = regmap_write(chip->regmap, KTD202X_REG_RESET_CONTROL, KTD202X_ENABLE_CTRL_WAKE);



	if (ret) {

		dev_err(chip->dev, "Failed to enable the chip: %d\n", ret);

		ktd202x_chip_disable(chip);

	}



	return ret;

}



static bool ktd202x_chip_in_use(struct ktd202x *chip)

{

	int i;



	for (i = 0; i < chip->num_leds; i++) {

		if (chip->leds[i].cdev.brightness)

			return true;

	}



	return false;

}



static int ktd202x_brightness_set(struct ktd202x_led *led,

				  struct mc_subled *subleds,

				  unsigned int num_channels)

{

	bool mode_blink = false;

	int channel;

	int state;

	int ret;

	int i;



	if (ktd202x_chip_in_use(led->chip)) {

		ret = ktd202x_chip_enable(led->chip);

		if (ret)

			return ret;

	}



	ret = regmap_read(led->chip->regmap, KTD202X_REG_CHANNEL_CTRL, &state);

	if (ret)

		return ret;



	/*

	 * In multicolor case, assume blink mode if PWM is set for at least one

	 * channel because another channel cannot be in state ON at the same time

	 */

	for (i = 0; i < num_channels; i++) {

		int channel_state;



		channel = subleds[i].channel;

		channel_state = (state >> 2 * channel) & KTD202X_CHANNEL_CTRL_MASK(0);

		if (channel_state == KTD202X_CHANNEL_CTRL_OFF)

			continue;

		mode_blink = channel_state == KTD202X_CHANNEL_CTRL_PWM1(0);

		break;

	}



	for (i = 0; i < num_channels; i++) {

		enum led_brightness brightness;

		int mode;



		brightness = subleds[i].brightness;

		channel = subleds[i].channel;



		if (brightness) {

			/* Register expects brightness between 0 and MAX_BRIGHTNESS - 1 */

			ret = regmap_write(led->chip->regmap, KTD202X_REG_LED_IOUT(channel),

					   brightness - 1);

			if (ret)

				return ret;



			if (mode_blink)

				mode = KTD202X_CHANNEL_CTRL_PWM1(channel);

			else

				mode = KTD202X_CHANNEL_CTRL_ON(channel);

		} else {

			mode = KTD202X_CHANNEL_CTRL_OFF;

		}

		ret = regmap_update_bits(led->chip->regmap, KTD202X_REG_CHANNEL_CTRL,

					 KTD202X_CHANNEL_CTRL_MASK(channel), mode);

		if (ret)

			return ret;

	}



	if (!ktd202x_chip_in_use(led->chip))

		return ktd202x_chip_disable(led->chip);



	return 0;

}



static int ktd202x_brightness_single_set(struct led_classdev *cdev,

					 enum led_brightness value)

{

	struct ktd202x_led *led = container_of(cdev, struct ktd202x_led, cdev);

	struct mc_subled info;

	int ret;



	cdev->brightness = value;



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



	info.brightness = value;

	info.channel = led->index;

	ret = ktd202x_brightness_set(led, &info, 1);



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



	return ret;

}



static int ktd202x_brightness_mc_set(struct led_classdev *cdev,

				     enum led_brightness value)

{

	struct led_classdev_mc *mc = lcdev_to_mccdev(cdev);

	struct ktd202x_led *led = container_of(mc, struct ktd202x_led, mcdev);

	int ret;



	cdev->brightness = value;



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



	led_mc_calc_color_components(mc, value);

	ret = ktd202x_brightness_set(led, mc->subled_info, mc->num_colors);



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



	return ret;

}



static int ktd202x_blink_set(struct ktd202x_led *led, unsigned long *delay_on,

			     unsigned long *delay_off, struct mc_subled *subleds,

			     unsigned int num_channels)

{

	unsigned long delay_total_ms;

	int ret, num_steps, on;

	u8 ctrl_mask = 0;

	u8 ctrl_pwm1 = 0;

	u8 ctrl_on = 0;

	int i;



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



	for (i = 0; i < num_channels; i++) {

		int channel = subleds[i].channel;



		ctrl_mask |= KTD202X_CHANNEL_CTRL_MASK(channel);

		ctrl_on |= KTD202X_CHANNEL_CTRL_ON(channel);

		ctrl_pwm1 |= KTD202X_CHANNEL_CTRL_PWM1(channel);

	}



	/* Never off - brightness is already set, disable blinking */

	if (!*delay_off) {

		ret = regmap_update_bits(led->chip->regmap, KTD202X_REG_CHANNEL_CTRL,

					 ctrl_mask, ctrl_on);

		goto out;

	}



	/* Convert into values the HW will understand. */



	/* Integer representation of time of flash period */

	num_steps = (*delay_on + *delay_off - KTD202X_FLASH_PERIOD_MIN_MS) /

		    KTD202X_FLASH_PERIOD_STEP_MS;

	num_steps = clamp(num_steps, 0, KTD202X_FLASH_PERIOD_MAX_STEPS);



	/* Integer representation of percentage of LED ON time */

	on = (*delay_on * KTD202X_FLASH_ON_MAX) / (*delay_on + *delay_off);



	/* Actually used delay_{on,off} values */

	delay_total_ms = num_steps * KTD202X_FLASH_PERIOD_STEP_MS + KTD202X_FLASH_PERIOD_MIN_MS;

	*delay_on = (delay_total_ms * on) / KTD202X_FLASH_ON_MAX;

	*delay_off = delay_total_ms - *delay_on;



	/* Set timings */

	ret = regmap_write(led->chip->regmap, KTD202X_REG_FLASH_PERIOD, num_steps);

	if (ret)

		goto out;



	ret = regmap_write(led->chip->regmap, KTD202X_REG_PWM1_TIMER, on);

	if (ret)

		goto out;



	ret = regmap_update_bits(led->chip->regmap, KTD202X_REG_CHANNEL_CTRL,

				 ctrl_mask, ctrl_pwm1);

out:

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

	return ret;

}



static int ktd202x_blink_single_set(struct led_classdev *cdev,

				    unsigned long *delay_on,

				    unsigned long *delay_off)

{

	struct ktd202x_led *led = container_of(cdev, struct ktd202x_led, cdev);

	struct mc_subled info;

	int ret;



	if (!cdev->brightness) {

		ret = ktd202x_brightness_single_set(cdev, KTD202X_MAX_BRIGHTNESS);

		if (ret)

			return ret;

	}



	/* If no blink specified, default to 1 Hz. */

	if (!*delay_off && !*delay_on) {

		*delay_off = 500;

		*delay_on = 500;

	}



	/* Never on - just set to off */

	if (!*delay_on)

		return ktd202x_brightness_single_set(cdev, LED_OFF);



	info.channel = led->index;



	return ktd202x_blink_set(led, delay_on, delay_off, &info, 1);

}



static int ktd202x_blink_mc_set(struct led_classdev *cdev,

				unsigned long *delay_on,

				unsigned long *delay_off)

{

	struct led_classdev_mc *mc = lcdev_to_mccdev(cdev);

	struct ktd202x_led *led = container_of(mc, struct ktd202x_led, mcdev);

	int ret;



	if (!cdev->brightness) {

		ret = ktd202x_brightness_mc_set(cdev, KTD202X_MAX_BRIGHTNESS);

		if (ret)

			return ret;

	}



	/* If no blink specified, default to 1 Hz. */

	if (!*delay_off && !*delay_on) {

		*delay_off = 500;

		*delay_on = 500;

	}



	/* Never on - just set to off */

	if (!*delay_on)

		return ktd202x_brightness_mc_set(cdev, LED_OFF);



	return ktd202x_blink_set(led, delay_on, delay_off, mc->subled_info,

				 mc->num_colors);

}



static int ktd202x_setup_led_rgb(struct ktd202x *chip, struct device_node *np,

				 struct ktd202x_led *led, struct led_init_data *init_data)

{

	struct led_classdev *cdev;

	struct device_node *child;

	struct mc_subled *info;

	int num_channels;

	int i = 0;



	num_channels = of_get_available_child_count(np);

	if (!num_channels || num_channels > chip->num_leds)

		return -EINVAL;



	info = devm_kcalloc(chip->dev, num_channels, sizeof(*info), GFP_KERNEL);

	if (!info)

		return -ENOMEM;



	for_each_available_child_of_node(np, child) {

		u32 mono_color;

		u32 reg;

		int ret;



		ret = of_property_read_u32(child, "reg", &reg);

		if (ret != 0 || reg >= chip->num_leds) {

			dev_err(chip->dev, "invalid 'reg' of %pOFn\n", child);

			of_node_put(child);

			return -EINVAL;

		}



		ret = of_property_read_u32(child, "color", &mono_color);

		if (ret < 0 && ret != -EINVAL) {

			dev_err(chip->dev, "failed to parse 'color' of %pOF\n", child);

			of_node_put(child);

			return ret;

		}



		info[i].color_index = mono_color;

		info[i].channel = reg;

		info[i].intensity = KTD202X_MAX_BRIGHTNESS;

		i++;

	}



	led->mcdev.subled_info = info;

	led->mcdev.num_colors = num_channels;



	cdev = &led->mcdev.led_cdev;

	cdev->brightness_set_blocking = ktd202x_brightness_mc_set;

	cdev->blink_set = ktd202x_blink_mc_set;



	return devm_led_classdev_multicolor_register_ext(chip->dev, &led->mcdev, init_data);

}



static int ktd202x_setup_led_single(struct ktd202x *chip, struct device_node *np,

				    struct ktd202x_led *led, struct led_init_data *init_data)

{

	struct led_classdev *cdev;

	u32 reg;

	int ret;



	ret = of_property_read_u32(np, "reg", &reg);

	if (ret != 0 || reg >= chip->num_leds) {

		dev_err(chip->dev, "invalid 'reg' of %pOFn\n", np);

		return -EINVAL;

	}

	led->index = reg;



	cdev = &led->cdev;

	cdev->brightness_set_blocking = ktd202x_brightness_single_set;

	cdev->blink_set = ktd202x_blink_single_set;



	return devm_led_classdev_register_ext(chip->dev, &led->cdev, init_data);

}



static int ktd202x_add_led(struct ktd202x *chip, struct device_node *np, unsigned int index)

{

	struct ktd202x_led *led = &chip->leds[index];

	struct led_init_data init_data = {};

	struct led_classdev *cdev;

	u32 color;

	int ret;



	/* Color property is optional in single color case */

	ret = of_property_read_u32(np, "color", &color);

	if (ret < 0 && ret != -EINVAL) {

		dev_err(chip->dev, "failed to parse 'color' of %pOF\n", np);

		return ret;

	}



	led->chip = chip;

	init_data.fwnode = of_fwnode_handle(np);



	if (color == LED_COLOR_ID_RGB) {

		cdev = &led->mcdev.led_cdev;

		ret = ktd202x_setup_led_rgb(chip, np, led, &init_data);

	} else {

		cdev = &led->cdev;

		ret = ktd202x_setup_led_single(chip, np, led, &init_data);

	}



	if (ret) {

		dev_err(chip->dev, "unable to register %s\n", cdev->name);

		return ret;

	}



	cdev->max_brightness = KTD202X_MAX_BRIGHTNESS;



	return 0;

}



static int ktd202x_probe_dt(struct ktd202x *chip)

{

	struct device_node *np = dev_of_node(chip->dev), *child;

	int count;

	int i = 0;



	chip->num_leds = (int)(unsigned long)of_device_get_match_data(chip->dev);



	count = of_get_available_child_count(np);

	if (!count || count > chip->num_leds)

		return -EINVAL;



	regmap_write(chip->regmap, KTD202X_REG_RESET_CONTROL, KTD202X_RSTR_RESET);



	/* Allow the device to execute the complete reset */

	usleep_range(200, 300);



	for_each_available_child_of_node(np, child) {

		int ret = ktd202x_add_led(chip, child, i);



		if (ret) {

			of_node_put(child);

			return ret;

		}

		i++;

	}



	return 0;

}



static const struct regmap_config ktd202x_regmap_config = {

	.reg_bits = 8,

	.val_bits = 8,

	.max_register = 0x09,

	.cache_type = REGCACHE_FLAT,

	.reg_defaults = ktd202x_reg_defaults,

	.num_reg_defaults = ARRAY_SIZE(ktd202x_reg_defaults),

};



static int ktd202x_probe(struct i2c_client *client)

{

	struct device *dev = &client->dev;

	struct ktd202x *chip;

	int count;

	int ret;



	count = device_get_child_node_count(dev);

	if (!count || count > KTD202X_MAX_LEDS)

		return dev_err_probe(dev, -EINVAL, "Incorrect number of leds (%d)", count);



	chip = devm_kzalloc(dev, struct_size(chip, leds, count), GFP_KERNEL);

	if (!chip)

		return -ENOMEM;



	chip->dev = dev;

	i2c_set_clientdata(client, chip);



	chip->regmap = devm_regmap_init_i2c(client, &ktd202x_regmap_config);

	if (IS_ERR(chip->regmap)) {

		ret = dev_err_probe(dev, PTR_ERR(chip->regmap),

				    "Failed to allocate register map.\n");

		return ret;

	}



	chip->regulators[0].supply = "vin";

	chip->regulators[1].supply = "vio";

	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(chip->regulators), chip->regulators);

	if (ret < 0) {

		dev_err_probe(dev, ret, "Failed to request regulators.\n");

		return ret;

	}



	ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators), chip->regulators);

	if (ret) {

		dev_err_probe(dev, ret, "Failed to enable regulators.\n");

		return ret;

	}



	ret = ktd202x_probe_dt(chip);

	if (ret < 0) {

		regulator_bulk_disable(ARRAY_SIZE(chip->regulators), chip->regulators);

		return ret;

	}



	ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators), chip->regulators);

	if (ret) {

		dev_err_probe(dev, ret, "Failed to disable regulators.\n");

		return ret;

	}



	mutex_init(&chip->mutex);



	return 0;

}



static void ktd202x_remove(struct i2c_client *client)

{

	struct ktd202x *chip = i2c_get_clientdata(client);



	ktd202x_chip_disable(chip);



	mutex_destroy(&chip->mutex);

}



static void ktd202x_shutdown(struct i2c_client *client)

{

	struct ktd202x *chip = i2c_get_clientdata(client);



	/* Reset registers to make sure all LEDs are off before shutdown */

	regmap_write(chip->regmap, KTD202X_REG_RESET_CONTROL, KTD202X_RSTR_RESET);

}



static const struct of_device_id ktd202x_match_table[] = {

	{ .compatible = "kinetic,ktd2026", .data = (void *)KTD2026_NUM_LEDS },

	{ .compatible = "kinetic,ktd2027", .data = (void *)KTD2027_NUM_LEDS },

	{},

};

MODULE_DEVICE_TABLE(of, ktd202x_match_table);



static struct i2c_driver ktd202x_driver = {

	.driver = {

		.name = "leds-ktd202x",

		.of_match_table = ktd202x_match_table,

	},

	.probe = ktd202x_probe,

	.remove = ktd202x_remove,

	.shutdown = ktd202x_shutdown,

};

module_i2c_driver(ktd202x_driver);



MODULE_AUTHOR("André Apitzsch <git@apitzsch.eu>");

MODULE_DESCRIPTION("Kinetic KTD2026/7 LED driver");

MODULE_LICENSE("GPL");