From 1b3303e7c105f894126169c2b0a167eec69d6335 Mon Sep 17 00:00:00 2001 From: edelweiseescala Date: Tue, 28 Oct 2025 15:52:13 +0800 Subject: [PATCH 1/3] dt-bindings: leds: ltc3220: Document LTC3220 18 channel LED Driver Add dt-binding for ltc3220. LTC3220 18 Channel LED driver Signed-off-by: Edelweise Escala --- .../bindings/leds/leds-ltc3220.yaml | 129 ++++++++++++++++++ 1 file changed, 129 insertions(+) create mode 100644 Documentation/devicetree/bindings/leds/leds-ltc3220.yaml diff --git a/Documentation/devicetree/bindings/leds/leds-ltc3220.yaml b/Documentation/devicetree/bindings/leds/leds-ltc3220.yaml new file mode 100644 index 00000000000000..c6426028367f3f --- /dev/null +++ b/Documentation/devicetree/bindings/leds/leds-ltc3220.yaml @@ -0,0 +1,129 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/leds/leds-ltc3220.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Analog Devices LTC3220 LED Drivers + +maintainers: + - Edelweise Escala + +description: Bindings for the Analog Devices LTC3220 18 channel LED Drivers. + + For more product information please see the link below + https://www.analog.com/en/products/ltc3220.html + +properties: + compatible: + enum: + - adi,ltc3220 + - adi,ltc3220-1 + + reg: + maxItems: 1 + + '#address-cells': + const: 1 + + '#size-cells': + const: 0 + + reset-gpios: + maxItems: 1 + description: GPIO attached to the chip's reset pin + + adi,force-cpo-mode: + $ref: /schemas/types.yaml#/definitions/uint32 + description: + Force charge pump operation mode. + 0 = Auto mode (default) - Automatically selects optimal charge pump mode + 1 = 1.5x mode - 1.5x voltage multiplication + 2 = 2x mode - 2x voltage multiplication + 3 = 1x mode - Charge pump bypass + minimum: 0 + maximum: 3 + default: 0 + + adi,quick-write-enable: + type: boolean + description: + Enable quick write mode. When enabled, writing to LED D1 (register 0x01) + will update all 18 LED outputs with the same brightness value. + +patternProperties: + "(^led@([1-9]|1[0-8])$|led)": + type: object + $ref: /schemas/leds/common.yaml# + unevaluatedProperties: false + properties: + reg: + description: Output channel for the LED (1-18 maps to LED outputs D1-D18) + minimum: 1 + maximum: 18 + required: + - reg + +required: + - compatible + - reg + +additionalProperties: false + +examples: + - | + #include + #include + + i2c { + #address-cells = <1>; + #size-cells = <0>; + + led-controller@1c { + compatible = "adi,ltc3220"; + reg = <0x1c>; + #address-cells = <1>; + #size-cells = <0>; + reset-gpios = <&gpio 17 GPIO_ACTIVE_LOW>; + adi,force-cpo-mode = <0>; + adi,quick-write-enable; + + led@1 { + reg = <1>; + function = LED_FUNCTION_INDICATOR; + function-enumerator = <1>; + }; + + led@2 { + reg = <2>; + function = LED_FUNCTION_INDICATOR; + function-enumerator = <2>; + }; + + led@3 { + reg = <3>; + function = LED_FUNCTION_INDICATOR; + function-enumerator = <3>; + }; + + led@4 { + reg = <4>; + function = LED_FUNCTION_INDICATOR; + function-enumerator = <4>; + }; + + led@5 { + reg = <5>; + function = LED_FUNCTION_INDICATOR; + function-enumerator = <5>; + }; + + led@6 { + reg = <6>; + function = LED_FUNCTION_INDICATOR; + function-enumerator = <6>; + }; + }; + }; + +... From 47028028fef324324f53889820aa712a0313b584 Mon Sep 17 00:00:00 2001 From: edelweiseescala Date: Tue, 28 Oct 2025 15:57:31 +0800 Subject: [PATCH 2/3] leds: ltc3220: add driver Add driver for ltc3220. LTC3220 18 Channel LED Driver Signed-off-by: Edelweise Escala --- drivers/leds/Kconfig | 10 + drivers/leds/Makefile | 1 + drivers/leds/leds-ltc3220.c | 469 ++++++++++++++++++++++++++++++++++++ 3 files changed, 480 insertions(+) create mode 100644 drivers/leds/leds-ltc3220.c diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index b784bb74a8378a..af6bb652d6dc65 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -931,6 +931,16 @@ config LEDS_LM36274 Say Y to enable the LM36274 LED driver for TI LMU devices. This supports the LED device LM36274. +config LEDS_LTC3220 + tristate "LED Driver for LTC3220/LTC3220-1" + depends on I2C && LEDS_CLASS + help + If you have an 18-Channel LED Driver connected to LTC3220, or LTC3220-1 + say Y here to enable this driver. + + To compile this driver as a module, choose M here: the module will + be called ltc3220. + config LEDS_TPS6105X tristate "LED support for TI TPS6105X" depends on LEDS_CLASS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 18afbb5a23ee5a..530bf81344ba84 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -58,6 +58,7 @@ obj-$(CONFIG_LEDS_LP8501) += leds-lp8501.o obj-$(CONFIG_LEDS_LP8788) += leds-lp8788.o obj-$(CONFIG_LEDS_LP8860) += leds-lp8860.o obj-$(CONFIG_LEDS_LT3593) += leds-lt3593.o +obj-$(CONFIG_LEDS_LTC3220) += leds-ltc3220.o obj-$(CONFIG_LEDS_MAX5970) += leds-max5970.o obj-$(CONFIG_LEDS_MAX77650) += leds-max77650.o obj-$(CONFIG_LEDS_MAX8997) += leds-max8997.o diff --git a/drivers/leds/leds-ltc3220.c b/drivers/leds/leds-ltc3220.c new file mode 100644 index 00000000000000..4bf6fb1056fbf4 --- /dev/null +++ b/drivers/leds/leds-ltc3220.c @@ -0,0 +1,469 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * LTC3220 18-Channel LED Driver + * + * Copyright 2025 Analog Devices Inc. + * + * Author: Edelweise Escala + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +/* LTC3220 Registers */ +#define LTC3220_COMMAND 0x00 +#define LTC3220_ULED01 0x01 +#define LTC3220_ULED02 0x02 +#define LTC3220_ULED03 0x03 +#define LTC3220_ULED04 0x04 +#define LTC3220_ULED05 0x05 +#define LTC3220_ULED06 0x06 +#define LTC3220_ULED07 0x07 +#define LTC3220_ULED08 0x08 +#define LTC3220_ULED09 0x09 +#define LTC3220_ULED10 0x0A +#define LTC3220_ULED11 0x0B +#define LTC3220_ULED12 0x0C +#define LTC3220_ULED13 0x0D +#define LTC3220_ULED14 0x0E +#define LTC3220_ULED15 0x0F +#define LTC3220_ULED16 0x10 +#define LTC3220_ULED17 0x11 +#define LTC3220_ULED18 0x12 +#define LTC3220_GRAD_BLINK 0x13 + +#define LTC3220_GRAD_COUNT_UP BIT(0) +#define LTC3220_COMMAND_QUICK_WRITE BIT(0) +#define LTC3220_COMMAND_SHUTDOWN BIT(3) + +#define LTC3220_LED_CURRENT_MASK GENMASK(5, 0) +#define LTC3220_LED_MODE_MASK GENMASK(7, 6) +#define LTC3220_BLINK_MASK GENMASK(4, 3) +#define LTC3220_GRADATION_MASK GENMASK(2, 1) +#define LTC3220_CPO_COMMAND_MASK GENMASK(2, 1) + +#define LTC3220_NUM_LEDS 18 + +struct ltc3220_command_cfg { + bool is_quick_write; + bool is_shutdown; + u8 force_cpo_mode; +}; + +struct ltc3220_uled_cfg { + u8 led_index; + u8 reg_value; + struct led_classdev led_cdev; + struct ltc3220_state *ltc3220_state; +}; + +struct ltc3220_grad_cfg { + bool is_increasing; + u8 gradation_period_ms; +}; + +struct ltc3220_state { + u8 blink_mode; + struct i2c_client *client; + struct ltc3220_command_cfg command_cfg; + struct ltc3220_uled_cfg uled_cfg[LTC3220_NUM_LEDS]; + struct ltc3220_grad_cfg grad_cfg; +}; + +static int ltc3220_set_command(struct ltc3220_state *ltc3220_state, + bool is_shutdown) +{ + u8 reg_val; + int ret; + struct i2c_client *client = ltc3220_state->client; + + reg_val = FIELD_PREP(LTC3220_COMMAND_SHUTDOWN, is_shutdown); + reg_val |= FIELD_PREP(LTC3220_CPO_COMMAND_MASK, + ltc3220_state->command_cfg.force_cpo_mode); + reg_val |= FIELD_PREP(LTC3220_COMMAND_QUICK_WRITE, + ltc3220_state->command_cfg.is_quick_write); + ret = i2c_smbus_write_byte_data(client, LTC3220_COMMAND, reg_val); + if (ret < 0) { + dev_err(&client->dev, "Set command fail\n"); + return ret; + } + + ltc3220_state->command_cfg.is_shutdown = is_shutdown; + + return 0; +} + +/* + * Set LED brightness and mode. + * The brightness value determines both the LED current and operating mode: + * 0-63: Normal mode - LED current from 0-63 (off to full brightness) + * 64-127: Blink mode - LED blinks with current level (brightness - 64) + * 128-191: Gradation mode - LED gradually changes brightness (brightness - 128) + * 192-255: GPO mode - LED operates as general purpose output (brightness - 192) + */ +static int ltc3220_set_led_data(struct led_classdev *led_cdev, + enum led_brightness brightness) +{ + int ret; + int i = 0; + struct ltc3220_state *ltc3220_state; + struct ltc3220_uled_cfg *uled_cfg; + + uled_cfg = container_of(led_cdev, struct ltc3220_uled_cfg, led_cdev); + ltc3220_state = uled_cfg->ltc3220_state; + + ret = i2c_smbus_write_byte_data(ltc3220_state->client, + LTC3220_ULED01 + uled_cfg->led_index, brightness); + if (ret < 0) + return ret; + + if (ltc3220_state->command_cfg.is_quick_write && uled_cfg->led_index == 0) { + for (i = 0; i < LTC3220_NUM_LEDS; i++) + ltc3220_state->uled_cfg[i].reg_value = brightness; + } else { + uled_cfg->reg_value = brightness; + } + return 0; +} + +static enum led_brightness ltc3220_get_led_data(struct led_classdev *led_cdev) +{ + struct ltc3220_uled_cfg *uled_cfg = container_of(led_cdev, struct ltc3220_uled_cfg, led_cdev); + + return uled_cfg->reg_value; +} + +static int ltc3220_set_blink_and_gradation(struct ltc3220_state *ltc3220_state, + u8 blink_cfg, u8 gradation_period_ms, bool is_increasing) +{ + u8 reg_val; + int ret; + struct i2c_client *client = ltc3220_state->client; + + reg_val = FIELD_PREP(LTC3220_BLINK_MASK, blink_cfg); + reg_val |= FIELD_PREP(LTC3220_GRADATION_MASK, gradation_period_ms); + reg_val |= FIELD_PREP(LTC3220_GRAD_COUNT_UP, is_increasing); + + ret = i2c_smbus_write_byte_data(client, LTC3220_GRAD_BLINK, reg_val); + if (ret < 0) { + dev_err(&client->dev, "Failed to set blink/gradation\n"); + return ret; + } + + return 0; +} + +/* + * LTC3220 pattern support for hardware-assisted breathing/gradation. + * The hardware supports 3 gradation ramp time 240ms, 480ms, 960ms) + * and can ramp up or down. + * + * Pattern array interpretation: + * pattern[0].brightness = start brightness (0-63) + * pattern[0].delta_t = ramp time in milliseconds + * pattern[1].brightness = end brightness (0-63) + * pattern[1].delta_t = (optional, can be 0 or same as pattern[0].delta_t) + */ +static int ltc3220_pattern_set(struct led_classdev *led_cdev, + struct led_pattern *pattern, + u32 len, int repeat) +{ + bool is_increasing; + struct ltc3220_state *ltc3220_state; + struct ltc3220_uled_cfg *uled_cfg; + u8 end_brightness; + u8 gradation_period; + u8 start_brightness; + int ret; + + uled_cfg = container_of(led_cdev, struct ltc3220_uled_cfg, led_cdev); + ltc3220_state = uled_cfg->ltc3220_state; + + if (len != 2) + return -EINVAL; + + start_brightness = pattern[0].brightness & LTC3220_LED_CURRENT_MASK; + end_brightness = pattern[1].brightness & LTC3220_LED_CURRENT_MASK; + + is_increasing = end_brightness > start_brightness; + + if (pattern[0].delta_t == 0) + gradation_period = 0; + else if (pattern[0].delta_t <= 240) + gradation_period = 1; + else if (pattern[0].delta_t <= 480) + gradation_period = 2; + else + gradation_period = 3; + + ret = ltc3220_set_blink_and_gradation(ltc3220_state, + ltc3220_state->blink_mode, + gradation_period, + is_increasing); + if (ret < 0) + return ret; + + ltc3220_state->grad_cfg.gradation_period_ms = gradation_period; + ltc3220_state->grad_cfg.is_increasing = is_increasing; + + ret = ltc3220_set_led_data(led_cdev, start_brightness); + if (ret < 0) + return ret; + + return ltc3220_set_led_data(led_cdev, 128 + end_brightness); +} + +static int ltc3220_pattern_clear(struct led_classdev *led_cdev) +{ + struct ltc3220_state *ltc3220_state; + struct ltc3220_uled_cfg *uled_cfg; + int ret; + + uled_cfg = container_of(led_cdev, struct ltc3220_uled_cfg, led_cdev); + ltc3220_state = uled_cfg->ltc3220_state; + + ret = ltc3220_set_blink_and_gradation(ltc3220_state, + ltc3220_state->blink_mode, + 0, false); + if (ret < 0) + return ret; + + ltc3220_state->grad_cfg.gradation_period_ms = 0; + ltc3220_state->grad_cfg.is_increasing = false; + + return 0; +} + +/* + * LTC3220 has a global blink configuration that affects all LEDs. + * This implementation allows per-LED blink requests, but the blink timing + * will be shared across all LEDs. The delay values are mapped to the + * hardware's discrete blink rates. + */ +static int ltc3220_blink_set(struct led_classdev *led_cdev, + unsigned long *delay_on, + unsigned long *delay_off) +{ + struct ltc3220_uled_cfg *uled_cfg; + struct ltc3220_state *ltc3220_state; + u8 blink_mode; + unsigned long period; + int ret; + + uled_cfg = container_of(led_cdev, struct ltc3220_uled_cfg, led_cdev); + ltc3220_state = uled_cfg->ltc3220_state; + + if (*delay_on == 0 && *delay_off == 0) { + blink_mode = 1; + *delay_on = 500; + *delay_off = 500; + } else { + period = *delay_on + *delay_off; + + if (period <= 750) { + blink_mode = 0; + *delay_on = 250; + *delay_off = 250; + } else if (period <= 1500) { + blink_mode = 1; + *delay_on = 500; + *delay_off = 500; + } else if (period <= 3000) { + blink_mode = 2; + *delay_on = 1000; + *delay_off = 1000; + } else { + blink_mode = 3; + *delay_on = 2000; + *delay_off = 2000; + } + } + + ret = ltc3220_set_blink_and_gradation(ltc3220_state, + blink_mode, + ltc3220_state->grad_cfg.gradation_period_ms, + ltc3220_state->grad_cfg.is_increasing); + if (ret < 0) + return ret; + + ltc3220_state->blink_mode = blink_mode; + + return 0; +} + +static void ltc3220_reset_gpio_action(void *data) +{ + struct gpio_desc *reset_gpio = data; + + if (reset_gpio) + gpiod_set_value_cansleep(reset_gpio, 1); +} + +static int ltc3220_reset(struct ltc3220_state *ltc3220_state, struct i2c_client *client) +{ + int i; + int ret; + struct gpio_desc *reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH); + + if (IS_ERR(reset_gpio)) + return dev_err_probe(&client->dev, PTR_ERR(reset_gpio), + "Failed to set reset GPIO\n"); + + if (reset_gpio) { + gpiod_set_value_cansleep(reset_gpio, 0); + + ret = devm_add_action_or_reset(&client->dev, ltc3220_reset_gpio_action, reset_gpio); + if (ret) + return ret; + + } else { + ret = ltc3220_set_command(ltc3220_state, 0); + if (ret < 0) + return ret; + + for (i = 0; i < LTC3220_NUM_LEDS; i++) { + ret = i2c_smbus_write_byte_data(client, LTC3220_ULED01 + i, 0); + if (ret < 0) + return ret; + } + + ret = ltc3220_set_blink_and_gradation(ltc3220_state, 0, 0, 0); + if (ret < 0) + return ret; + + } + + return 0; +} + +static void ltc3220_remove(struct i2c_client *client) +{ + struct ltc3220_state *ltc3220_state = i2c_get_clientdata(client); + + ltc3220_set_command(ltc3220_state, true); +} + +static int ltc3220_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct ltc3220_state *ltc3220_state = i2c_get_clientdata(client); + + return ltc3220_set_command(ltc3220_state, true); +} + +static int ltc3220_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct ltc3220_state *ltc3220_state = i2c_get_clientdata(client); + + return ltc3220_set_command(ltc3220_state, false); +} + +static SIMPLE_DEV_PM_OPS(ltc3220_pm_ops, ltc3220_suspend, ltc3220_resume); + +static int ltc3220_probe(struct i2c_client *client) +{ + u8 i = 0; + int ret; + struct ltc3220_state *ltc3220_state; + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_BYTE_DATA)) + return dev_err_probe(&client->dev, -EIO, + "SMBUS Byte Data not Supported\n"); + + ltc3220_state = devm_kzalloc(&client->dev, sizeof(*ltc3220_state), GFP_KERNEL); + if (!ltc3220_state) + return dev_err_probe(&client->dev, -ENOMEM, + "Failed to allocate memory\n"); + + ltc3220_state->client = client; + i2c_set_clientdata(client, ltc3220_state); + + ret = ltc3220_reset(ltc3220_state, client); + if (ret) + return dev_err_probe(&client->dev, ret, + "Failed to reset device\n"); + + ret = device_property_read_u8(&client->dev, "adi,force-cpo-mode", + <c3220_state->command_cfg.force_cpo_mode); + if (ret) + ltc3220_state->command_cfg.force_cpo_mode = 0; + + if (ltc3220_state->command_cfg.force_cpo_mode > 3) + return dev_err_probe(&client->dev, -EINVAL, + "Invalid adi,force-cpo-mode %u, must be 0-3\n", + ltc3220_state->command_cfg.force_cpo_mode); + + if (device_property_read_bool(&client->dev, "adi,quick-write-enable")) + ltc3220_state->command_cfg.is_quick_write = true; + + ret = ltc3220_set_command(ltc3220_state, 0); + if (ret < 0) + return dev_err_probe(&client->dev, ret, + "Failed to set command\n"); + + device_for_each_child_node_scoped(&client->dev, child) { + u32 source; + struct led_init_data init_data = {}; + + ret = fwnode_property_read_u32(child, "reg", &source); + if (ret != 0 || !source || source > LTC3220_NUM_LEDS) + return dev_err_probe(&client->dev, ret ? ret : -EINVAL, + "Couldn't read LED address\n"); + + /* LED node reg/index/address goes from 1 to 18 */ + i = source - 1; + init_data.fwnode = child; + init_data.devicename = "ltc3220"; + init_data.devname_mandatory = true; + + ltc3220_state->uled_cfg[i].led_index = i; + ltc3220_state->uled_cfg[i].reg_value = 0; + ltc3220_state->uled_cfg[i].ltc3220_state = ltc3220_state; + ltc3220_state->uled_cfg[i].led_cdev.brightness_set_blocking = ltc3220_set_led_data; + ltc3220_state->uled_cfg[i].led_cdev.brightness_get = ltc3220_get_led_data; + ltc3220_state->uled_cfg[i].led_cdev.blink_set = ltc3220_blink_set; + ltc3220_state->uled_cfg[i].led_cdev.pattern_set = ltc3220_pattern_set; + ltc3220_state->uled_cfg[i].led_cdev.pattern_clear = ltc3220_pattern_clear; + ltc3220_state->uled_cfg[i].led_cdev.max_brightness = 255; + + ret = devm_led_classdev_register_ext(&client->dev, + <c3220_state->uled_cfg[i].led_cdev, + &init_data); + if (ret) + return dev_err_probe(&client->dev, ret, + "Failed to register LED class device\n"); + } + + return 0; +} + +static const struct of_device_id ltc3220_of_match[] = { + { .compatible = "adi,ltc3220", }, + { .compatible = "adi,ltc3220-1", }, + { }, +}; +MODULE_DEVICE_TABLE(of, ltc3220_of_match); + +static struct i2c_driver ltc3220_led_driver = { + .driver = { + .name = "ltc3220", + .of_match_table = ltc3220_of_match, + .pm = pm_sleep_ptr(<c3220_pm_ops), + }, + .probe = ltc3220_probe, + .remove = ltc3220_remove, +}; + +module_i2c_driver(ltc3220_led_driver); + +MODULE_AUTHOR("Edelweise Escala "); +MODULE_DESCRIPTION("LED driver for LTC3220 controllers"); +MODULE_LICENSE("GPL"); From 007f3b386176401f6e173eb798e639095466b905 Mon Sep 17 00:00:00 2001 From: edelweiseescala Date: Tue, 28 Oct 2025 15:59:40 +0800 Subject: [PATCH 3/3] leds: Kconfig.adi: imply ltc3220 Add entry for LTC3220 driver Signed-off-by: Edelweise Escala --- Kconfig.adi | 1 + 1 file changed, 1 insertion(+) diff --git a/Kconfig.adi b/Kconfig.adi index b55ae80169496b..1a83bd4be01e6a 100644 --- a/Kconfig.adi +++ b/Kconfig.adi @@ -71,6 +71,7 @@ config KERNEL_ALL_ADI_DRIVERS imply PMIC_ADP5520 imply PWM_AXI_PWMGEN imply LEDS_ADP5520 + imply LEDS_LTC3220 imply BACKLIGHT_ADP5520 imply BACKLIGHT_ADP8860 imply BACKLIGHT_ADP8870