// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Kinetic KTD2026/7 RGB/White LED driver with I2C interface
*
* Copyright 2023 André Apitzsch <[email protected]>
*
* 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;
unsigned long 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 fwnode_handle *fwnode,
struct ktd202x_led *led, struct led_init_data *init_data)
{
struct fwnode_handle *child;
struct led_classdev *cdev;
struct mc_subled *info;
int num_channels;
int i = 0;
num_channels = 0;
fwnode_for_each_available_child_node(fwnode, child)
num_channels++;
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;
fwnode_for_each_available_child_node(fwnode, child) {
u32 mono_color;
u32 reg;
int ret;
ret = fwnode_property_read_u32(child, "reg", ®);
if (ret != 0 || reg >= chip->num_leds) {
dev_err(chip->dev, "invalid 'reg' of %pfw\n", child);
fwnode_handle_put(child);
return ret;
}
ret = fwnode_property_read_u32(child, "color", &mono_color);
if (ret < 0 && ret != -EINVAL) {
dev_err(chip->dev, "failed to parse 'color' of %pfw\n", child);
fwnode_handle_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 fwnode_handle *fwnode,
struct ktd202x_led *led, struct led_init_data *init_data)
{
struct led_classdev *cdev;
u32 reg;
int ret;
ret = fwnode_property_read_u32(fwnode, "reg", ®);
if (ret != 0 || reg >= chip->num_leds) {
dev_err(chip->dev, "invalid 'reg' of %pfw\n", fwnode);
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 fwnode_handle *fwnode, 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 = fwnode_property_read_u32(fwnode, "color", &color);
if (ret < 0 && ret != -EINVAL) {
dev_err(chip->dev, "failed to parse 'color' of %pfw\n", fwnode);
return ret;
}
led->chip = chip;
init_data.fwnode = fwnode;
if (color == LED_COLOR_ID_RGB) {
cdev = &led->mcdev.led_cdev;
ret = ktd202x_setup_led_rgb(chip, fwnode, led, &init_data);
} else {
cdev = &led->cdev;
ret = ktd202x_setup_led_single(chip, fwnode, 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_fw(struct ktd202x *chip)
{
struct fwnode_handle *child;
struct device *dev = chip->dev;
int count;
int i = 0;
count = device_get_child_node_count(dev);
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);
device_for_each_child_node(dev, child) {
int ret = ktd202x_add_led(chip, child, i);
if (ret) {
fwnode_handle_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;
}
ret = devm_mutex_init(dev, &chip->mutex);
if (ret)
return ret;
chip->num_leds = (unsigned long)i2c_get_match_data(client);
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_fw(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;
}
return 0;
}
static void ktd202x_remove(struct i2c_client *client)
{
struct ktd202x *chip = i2c_get_clientdata(client);
ktd202x_chip_disable(chip);
}
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 i2c_device_id ktd202x_id[] = {
{"ktd2026", KTD2026_NUM_LEDS},
{"ktd2027", KTD2027_NUM_LEDS},
{}
};
MODULE_DEVICE_TABLE(i2c, ktd202x_id);
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,
.id_table = ktd202x_id,
};
module_i2c_driver(ktd202x_driver);
MODULE_AUTHOR("André Apitzsch <[email protected]>");
MODULE_DESCRIPTION("Kinetic KTD2026/7 LED driver");
MODULE_LICENSE("GPL");
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