diff --git a/MAINTAINERS b/MAINTAINERS index c422939a8269..a1eb0937238d 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -15533,6 +15533,7 @@ L: linux-leds@vger.kernel.org S: Maintained W: https://ez.analog.com/linux-software-drivers F: Documentation/devicetree/bindings/leds/adi,ltc3208.yaml +F: drivers/leds/leds-ltc3208.c LTC3220 LED DRIVER M: Edelweise Escala diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index d0d3182236be..7ec2c8d78542 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -1042,6 +1042,18 @@ config LEDS_ACER_A500 This option enables support for the Power Button LED of Acer Iconia Tab A500. +config LEDS_LTC3208 + tristate "LED Driver for Analog Devices LTC3208" + depends on LEDS_CLASS && I2C + select REGMAP_I2C + help + Say Y to enable the LTC3208 LED driver. + This enables the LED device LTC3208, a 7-channel, 17-current source + multidisplay high-current LED driver, configured via I2C. + + To compile this driver as a module, choose M here: the module will + be called ltc3208. + source "drivers/leds/blink/Kconfig" comment "Flash and Torch LED drivers" diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index a68244bd50fb..4d4b089156e2 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -61,6 +61,7 @@ obj-$(CONFIG_LEDS_LP8788) += leds-lp8788.o obj-$(CONFIG_LEDS_LP8860) += leds-lp8860.o obj-$(CONFIG_LEDS_LP8864) += leds-lp8864.o obj-$(CONFIG_LEDS_LT3593) += leds-lt3593.o +obj-$(CONFIG_LEDS_LTC3208) += leds-ltc3208.o obj-$(CONFIG_LEDS_LTC3220) += leds-ltc3220.o obj-$(CONFIG_LEDS_MAX5970) += leds-max5970.o obj-$(CONFIG_LEDS_MAX77650) += leds-max77650.o diff --git a/drivers/leds/leds-ltc3208.c b/drivers/leds/leds-ltc3208.c new file mode 100644 index 000000000000..64091f29f18a --- /dev/null +++ b/drivers/leds/leds-ltc3208.c @@ -0,0 +1,234 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * LED driver for Analog Devices LTC3208 Multi-Display Driver + * + * Copyright 2026 Analog Devices Inc. + * + * Author: Jan Carlo Roleda + * + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Registers */ +#define LTC3208_REG_A_GRNRED_CURRENT 0x1 /* Green and Red current DAC */ +#define LTC3208_REG_B_AUXBLU_CURRENT 0x2 /* AUX and Blue current DAC */ +#define LTC3208_REG_C_MAIN_CURRENT 0x3 /* Main current DAC */ +#define LTC3208_REG_D_SUB_CURRENT 0x4 /* Sub current DAC */ +#define LTC3208_REG_E_AUX_SELECT 0x5 /* AUX DAC Select */ +#define LTC3208_AUX1_MASK GENMASK(1, 0) +#define LTC3208_AUX2_MASK GENMASK(3, 2) +#define LTC3208_AUX3_MASK GENMASK(5, 4) +#define LTC3208_AUX4_MASK GENMASK(7, 6) +#define LTC3208_REG_F_CAM_CURRENT 0x6 /* CAM (High and Low) current DAC */ +#define LTC3208_REG_G_OPT 0x7 /* Device Options */ +#define LTC3208_OPT_CPO_MASK GENMASK(7, 6) +#define LTC3208_OPT_DIS_RGBDROP BIT(3) +#define LTC3208_OPT_DIS_CAMHILO BIT(2) +#define LTC3208_OPT_EN_RGBS BIT(1) + +#define LTC3208_MAX_BRIGHTNESS_4BIT 0xF +#define LTC3208_MAX_BRIGHTNESS_8BIT 0xFF + +#define LTC3208_NUM_AUX_LEDS 4 /* Number of configurable aux channels */ +#define LTC3208_NUM_REGS 7 /* Number of available registers to access */ + +enum ltc3208_aux_channel { + LTC3208_AUX_CHAN_AUX = 0, + LTC3208_AUX_CHAN_MAIN, + LTC3208_AUX_CHAN_SUB, + LTC3208_AUX_CHAN_CAM +}; + +enum ltc3208_channel { + LTC3208_CHAN_MAIN = 0, + LTC3208_CHAN_SUB, + LTC3208_CHAN_AUX, + LTC3208_CHAN_CAML, + LTC3208_CHAN_CAMH, + LTC3208_CHAN_RED, + LTC3208_CHAN_BLUE, + LTC3208_CHAN_GREEN, + LTC3208_CHAN_N_COUNT, +}; + +static const char *const ltc3208_dt_aux_channels[] = { + "adi,aux1-channel", + "adi,aux2-channel", + "adi,aux3-channel", + "adi,aux4-channel" +}; + +static const char *const ltc3208_aux_opt[] = { "aux", "main", "sub", "cam" }; + +struct ltc3208_led { + struct led_classdev cdev; + struct regmap_field *rfield; +}; + +static const struct reg_default ltc3208_reg_defaults[] = { + { LTC3208_REG_A_GRNRED_CURRENT, 0 }, + { LTC3208_REG_B_AUXBLU_CURRENT, 0 }, + { LTC3208_REG_C_MAIN_CURRENT, 0 }, + { LTC3208_REG_D_SUB_CURRENT, 0 }, + { LTC3208_REG_E_AUX_SELECT, 0 }, + { LTC3208_REG_F_CAM_CURRENT, 0 }, + { LTC3208_REG_G_OPT, 0 } +}; + +static const struct regmap_config ltc3208_regmap_cfg = { + .reg_bits = 8, + .val_bits = 8, + .max_register = LTC3208_REG_G_OPT, + .cache_type = REGCACHE_FLAT_S, + .reg_defaults = ltc3208_reg_defaults, + .num_reg_defaults = LTC3208_NUM_REGS, +}; + +static const struct reg_field ltc3208_led_reg_field[LTC3208_CHAN_N_COUNT] = { + [LTC3208_CHAN_MAIN] = REG_FIELD(LTC3208_REG_C_MAIN_CURRENT, 0, 7), + [LTC3208_CHAN_SUB] = REG_FIELD(LTC3208_REG_D_SUB_CURRENT, 0, 7), + [LTC3208_CHAN_BLUE] = REG_FIELD(LTC3208_REG_B_AUXBLU_CURRENT, 0, 3), + [LTC3208_CHAN_AUX] = REG_FIELD(LTC3208_REG_B_AUXBLU_CURRENT, 4, 7), + [LTC3208_CHAN_CAML] = REG_FIELD(LTC3208_REG_F_CAM_CURRENT, 0, 3), + [LTC3208_CHAN_CAMH] = REG_FIELD(LTC3208_REG_F_CAM_CURRENT, 4, 7), + [LTC3208_CHAN_RED] = REG_FIELD(LTC3208_REG_A_GRNRED_CURRENT, 0, 3), + [LTC3208_CHAN_GREEN] = REG_FIELD(LTC3208_REG_A_GRNRED_CURRENT, 4, 7), +}; + +static int ltc3208_led_set_brightness(struct led_classdev *led_cdev, enum led_brightness brightness) +{ + struct ltc3208_led *led = container_of(led_cdev, struct ltc3208_led, cdev); + u8 current_level = brightness; + + return regmap_field_write(led->rfield, current_level); +} + +static int ltc3208_probe(struct i2c_client *client) +{ + enum ltc3208_aux_channel aux_channels[LTC3208_NUM_AUX_LEDS]; + DECLARE_BITMAP(registered_chans, LTC3208_CHAN_N_COUNT) = { }; + struct regmap *regmap; + bool disable_rgb_aux4_dropout_signal; + bool disable_camhl_pin; + bool set_sub_control_pin; + int ret; + u8 dev_options; + + regmap = devm_regmap_init_i2c(client, <c3208_regmap_cfg); + if (IS_ERR(regmap)) + return dev_err_probe(&client->dev, PTR_ERR(regmap), "Failed to initialize regmap"); + + regcache_mark_dirty(regmap); + ret = regcache_sync(regmap); + if (ret) + return dev_err_probe(&client->dev, ret, "Failed to sync register cache"); + + disable_camhl_pin = device_property_read_bool(&client->dev, "adi,disable-camhl-pin"); + + set_sub_control_pin = device_property_read_bool(&client->dev, "adi,cfg-enrgbs-pin"); + + disable_rgb_aux4_dropout_signal = + device_property_read_bool(&client->dev, "adi,disable-rgb-aux4-dropout"); + + dev_options = FIELD_PREP(LTC3208_OPT_EN_RGBS, set_sub_control_pin) | + FIELD_PREP(LTC3208_OPT_DIS_CAMHILO, disable_camhl_pin) | + FIELD_PREP(LTC3208_OPT_CPO_MASK, 0) | + FIELD_PREP(LTC3208_OPT_DIS_RGBDROP, disable_rgb_aux4_dropout_signal); + + ret = regmap_write(regmap, LTC3208_REG_G_OPT, dev_options); + if (ret) + return dev_err_probe(&client->dev, ret, "Failed to set device options register"); + + /* Initialize AUX channel configurations */ + for (int i = 0; i < LTC3208_NUM_AUX_LEDS; i++) { + /* Default value (AUX) if property is not present in DT */ + if (!device_property_present(&client->dev, ltc3208_dt_aux_channels[i])) { + aux_channels[i] = LTC3208_AUX_CHAN_AUX; + continue; + } + + ret = device_property_match_property_string(&client->dev, + ltc3208_dt_aux_channels[i], + ltc3208_aux_opt, LTC3208_NUM_AUX_LEDS); + if (ret < 0) + return dev_err_probe(&client->dev, ret, "Error reading AUX Channel %d", i); + + aux_channels[i] = ret; + } + + dev_options = FIELD_PREP(LTC3208_AUX1_MASK, aux_channels[0]) | + FIELD_PREP(LTC3208_AUX2_MASK, aux_channels[1]) | + FIELD_PREP(LTC3208_AUX3_MASK, aux_channels[2]) | + FIELD_PREP(LTC3208_AUX4_MASK, aux_channels[3]); + + ret = regmap_write(regmap, LTC3208_REG_E_AUX_SELECT, dev_options); + if (ret) + return dev_err_probe(&client->dev, ret, "Error writing to aux channel register"); + + device_for_each_child_node_scoped(&client->dev, child) { + struct ltc3208_led *led; + struct led_init_data init_data = { }; + u32 chan; + + ret = fwnode_property_read_u32(child, "reg", &chan); + if (ret) + return dev_err_probe(&client->dev, ret, + "Failed to get register value of LED"); + if (chan >= LTC3208_CHAN_N_COUNT) + return dev_err_probe(&client->dev, -EINVAL, "%u is an invalid LED ID", + chan); + if (test_and_set_bit(chan, registered_chans)) + return dev_err_probe(&client->dev, -EINVAL, "%u is already registered", + chan); + + led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL); + if (!led) + return -ENOMEM; + + led->rfield = devm_regmap_field_alloc(&client->dev, regmap, + ltc3208_led_reg_field[chan]); + if (IS_ERR(led->rfield)) + return dev_err_probe(&client->dev, PTR_ERR(led->rfield), + "Cannot allocate regmap field"); + led->cdev.brightness_set_blocking = ltc3208_led_set_brightness; + led->cdev.max_brightness = LTC3208_MAX_BRIGHTNESS_4BIT; + + if (chan == LTC3208_CHAN_MAIN || chan == LTC3208_CHAN_SUB) + led->cdev.max_brightness = LTC3208_MAX_BRIGHTNESS_8BIT; + + init_data.fwnode = child; + + ret = devm_led_classdev_register_ext(&client->dev, &led->cdev, &init_data); + if (ret) + return dev_err_probe(&client->dev, ret, "Failed to register LED %u", chan); + } + + return 0; +} + +static const struct of_device_id ltc3208_match_table[] = { + { .compatible = "adi,ltc3208" }, + { } +}; +MODULE_DEVICE_TABLE(of, ltc3208_match_table); + +static struct i2c_driver ltc3208_driver = { + .driver = { + .name = "ltc3208", + .of_match_table = ltc3208_match_table, + }, + .probe = ltc3208_probe, +}; +module_i2c_driver(ltc3208_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jan Carlo Roleda "); +MODULE_DESCRIPTION("LTC3208 LED Driver");