// SPDX-License-Identifier: GPL-2.0-only /* * Silergy SY7758 6-channel High Efficiency LED Driver * * Copyright (C) 2025 Kancy Joe * Copyright (C) 2026 Linaro Limited * Author: Neil Armstrong */ #include #include #include #include #include #include #include #include #include #include #include #define DEFAULT_BRIGHTNESS 1024 #define MAX_BRIGHTNESS 4080 #define REG_MAX 0xAE /* Registers */ #define REG_DEV_CTL 0x01 #define REG_DEV_ID 0x03 #define REG_BRT_12BIT_L 0x10 #define REG_BRT_12BIT_H 0x11 /* OTP memory */ #define REG_OTP_CFG0 0xA0 #define REG_OTP_CFG1 0xA1 #define REG_OTP_CFG2 0xA2 #define REG_OTP_CFG5 0xA5 #define REG_OTP_CFG9 0xA9 /* Fields */ #define BIT_DEV_CTL_FAST BIT(7) #define MSK_DEV_CTL_BRT_MODE GENMASK(2, 1) #define BIT_DEV_CTL_BL_CTLB BIT(0) #define MSK_BRT_12BIT_L GENMASK(7, 0) #define MSK_BRT_12BIT_H GENMASK(3, 0) #define MSK_CFG0_CURRENT_LOW GENMASK(7, 0) #define BIT_CFG1_PDET_STDBY BIT(7) #define MSK_CFG1_CURRENT_MAX GENMASK(6, 4) #define MSK_CFG1_CURRENT_HIGH GENMASK(3, 0) #define BIT_CFG2_UVLO_EN BIT(5) #define BIT_CFG2_UVLO_TH BIT(4) #define BIT_CFG2_BL_ON BIT(3) #define BIT_CFG2_ISET_EN BIT(2) #define BIT_CFG2_BST_ESET_EN BIT(1) #define BIT_CFG5_PWM_DIRECT BIT(7) #define MSK_CFG5_PS_MODE GENMASK(6, 4) #define MSK_CFG5_PWM_FREQ GENMASK(3, 0) #define MSK_CFG9_VBST_MAX GENMASK(7, 5) #define BIT_CFG9_JUMP_EN BIT(4) #define MSK_CFG9_JUMP_TH GENMASK(3, 2) #define MSK_CFG9_JUMP_VOLTAGE GENMASK(1, 0) struct sy7758 { struct i2c_client *client; struct regmap *regmap; struct gpio_desc *gpio; struct backlight_device *bl; }; static const struct regmap_config sy7758_regmap_config = { .reg_bits = 8, .val_bits = 8, .max_register = REG_MAX, }; static int sy7758_backlight_update_status(struct backlight_device *backlight_dev) { struct sy7758 *sydev = bl_get_data(backlight_dev); unsigned int brightness = backlight_get_brightness(backlight_dev); int ret; ret = regmap_write(sydev->regmap, REG_BRT_12BIT_L, FIELD_PREP(MSK_BRT_12BIT_L, brightness & 0xff)); if (ret) return ret; ret = regmap_write(sydev->regmap, REG_BRT_12BIT_H, FIELD_PREP(MSK_BRT_12BIT_H, (brightness >> 8) & 0xf)); if (ret) return ret; return 0; } static const struct backlight_ops sy7758_backlight_ops = { .options = BL_CORE_SUSPENDRESUME, .update_status = sy7758_backlight_update_status, }; static int sy7758_init(struct sy7758 *sydev) { int ret = 0; ret = regmap_write(sydev->regmap, REG_DEV_CTL, BIT_DEV_CTL_FAST | BIT_DEV_CTL_BL_CTLB | FIELD_PREP(MSK_DEV_CTL_BRT_MODE, 2)); if (ret) return ret; ret = regmap_write(sydev->regmap, REG_BRT_12BIT_L, FIELD_PREP(MSK_BRT_12BIT_L, DEFAULT_BRIGHTNESS & 0xff)); if (ret) return ret; ret = regmap_write(sydev->regmap, REG_BRT_12BIT_H, FIELD_PREP(MSK_BRT_12BIT_H, (DEFAULT_BRIGHTNESS >> 8))); if (ret) return ret; ret = regmap_write(sydev->regmap, REG_OTP_CFG5, FIELD_PREP(MSK_CFG5_PS_MODE, 6) | FIELD_PREP(MSK_CFG5_PWM_FREQ, 4)); if (ret) return ret; ret = regmap_write(sydev->regmap, REG_OTP_CFG0, FIELD_PREP(MSK_CFG0_CURRENT_LOW, 85)); if (ret) return ret; ret = regmap_write(sydev->regmap, REG_OTP_CFG1, BIT_CFG1_PDET_STDBY | FIELD_PREP(MSK_CFG1_CURRENT_MAX, 1) | FIELD_PREP(MSK_CFG1_CURRENT_HIGH, 10)); if (ret) return ret; ret = regmap_write(sydev->regmap, REG_OTP_CFG9, FIELD_PREP(MSK_CFG9_VBST_MAX, 4)); if (ret) return ret; ret = regmap_write(sydev->regmap, REG_OTP_CFG2, BIT_CFG2_BL_ON | BIT_CFG2_UVLO_EN); if (ret) return ret; return 0; } static int sy7758_probe(struct i2c_client *client) { struct backlight_properties props = { }; struct device *dev = &client->dev; struct sy7758 *sydev; unsigned int dev_id; int ret; sydev = devm_kzalloc(dev, sizeof(*sydev), GFP_KERNEL); if (!sydev) return -ENOMEM; i2c_set_clientdata(client, sydev); /* Initialize regmap */ sydev->client = client; sydev->regmap = devm_regmap_init_i2c(client, &sy7758_regmap_config); if (IS_ERR(sydev->regmap)) return dev_err_probe(dev, PTR_ERR(sydev->regmap), "failed to init regmap\n"); /* Get and enable regulator */ ret = devm_regulator_get_enable(dev, "vdd"); if (ret) return dev_err_probe(dev, ret, "failed to get regulator\n"); fsleep(100); /* Get enable GPIO and set to high */ sydev->gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_HIGH); if (IS_ERR(sydev->gpio)) return dev_err_probe(dev, PTR_ERR(sydev->gpio), "failed to get enable GPIO\n"); /* Let some time for HW to settle */ fsleep(10000); /* try read and check device id */ ret = regmap_read(sydev->regmap, REG_DEV_ID, &dev_id); if (ret < 0) return dev_err_probe(dev, ret, "failed to read device id\n"); if (dev_id != 0x63) { dev_err(dev, "unexpected device id: 0x%02x\n", dev_id); return -ENODEV; } /* Initialize and set default brightness */ ret = sy7758_init(sydev); if (ret) return ret; props.type = BACKLIGHT_RAW; props.max_brightness = MAX_BRIGHTNESS; props.brightness = DEFAULT_BRIGHTNESS; props.scale = BACKLIGHT_SCALE_LINEAR; sydev->bl = devm_backlight_device_register(dev, "sy7758-backlight", dev, sydev, &sy7758_backlight_ops, &props); if (IS_ERR(sydev->bl)) return dev_err_probe(dev, PTR_ERR(sydev->bl), "failed to register backlight device\n"); return backlight_update_status(sydev->bl); } static void sy7758_remove(struct i2c_client *client) { struct sy7758 *sydev = i2c_get_clientdata(client); backlight_disable(sydev->bl); } static const struct i2c_device_id sy7758_ids[] = { { "sy7758" }, { } }; MODULE_DEVICE_TABLE(i2c, sy7758_ids); static const struct of_device_id sy7758_match_table[] = { { .compatible = "silergy,sy7758", }, { }, }; MODULE_DEVICE_TABLE(of, sy7758_match_table); static struct i2c_driver sy7758_driver = { .driver = { .name = "sy7758", .of_match_table = sy7758_match_table, }, .probe = sy7758_probe, .remove = sy7758_remove, .id_table = sy7758_ids, }; module_i2c_driver(sy7758_driver); MODULE_DESCRIPTION("Silergy SY7758 Backlight Driver"); MODULE_AUTHOR("Kancy Joe "); MODULE_AUTHOR("Neil Armstrong "); MODULE_LICENSE("GPL");