This is a general driver for LM3509 backlight chip of TI. LM3509 is High Efficiency Boost for White LEDs and/or OLED Displays with Dual Current Sinks. This driver supports OLED/White LED select, brightness control and sub/main control. The datasheet can be found at http://www.ti.com/product/lm3509. Signed-off-by: Patrick Gansterer <paroga@xxxxxxxxxx> --- drivers/video/backlight/Kconfig | 7 + drivers/video/backlight/Makefile | 1 + drivers/video/backlight/lm3509_bl.c | 340 ++++++++++++++++++++++++++++ 3 files changed, 348 insertions(+) create mode 100644 drivers/video/backlight/lm3509_bl.c diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index 230bca07b09d..3614a5d29c71 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -373,6 +373,13 @@ config BACKLIGHT_AAT2870 If you have a AnalogicTech AAT2870 say Y to enable the backlight driver. +config BACKLIGHT_LM3509 + tristate "Backlight Driver for LM3509" + depends on I2C + select REGMAP_I2C + help + This supports TI LM3509 Backlight Driver + config BACKLIGHT_LM3630A tristate "Backlight Driver for LM3630A" depends on I2C && PWM diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile index 8d2cb252042d..8fc98f760a8a 100644 --- a/drivers/video/backlight/Makefile +++ b/drivers/video/backlight/Makefile @@ -36,6 +36,7 @@ obj-$(CONFIG_BACKLIGHT_IPAQ_MICRO) += ipaq_micro_bl.o obj-$(CONFIG_BACKLIGHT_KTD253) += ktd253-backlight.o obj-$(CONFIG_BACKLIGHT_KTD2801) += ktd2801-backlight.o obj-$(CONFIG_BACKLIGHT_KTZ8866) += ktz8866.o +obj-$(CONFIG_BACKLIGHT_LM3509) += lm3509_bl.o obj-$(CONFIG_BACKLIGHT_LM3533) += lm3533_bl.o obj-$(CONFIG_BACKLIGHT_LM3630A) += lm3630a_bl.o obj-$(CONFIG_BACKLIGHT_LM3639) += lm3639_bl.o diff --git a/drivers/video/backlight/lm3509_bl.c b/drivers/video/backlight/lm3509_bl.c new file mode 100644 index 000000000000..ab57f79ffe23 --- /dev/null +++ b/drivers/video/backlight/lm3509_bl.c @@ -0,0 +1,340 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +#include <linux/backlight.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/regmap.h> + +#define LM3509_NAME "lm3509_bl" + +#define LM3509_SINK_MAIN 0 +#define LM3509_SINK_SUB 1 +#define LM3509_NUM_SINKS 2 + +#define LM3509_DEF_BRIGHTNESS 0x12 +#define LM3509_MAX_BRIGHTNESS 0x1F + +#define REG_GP 0x10 +#define REG_BMAIN 0xA0 +#define REG_BSUB 0xB0 +#define REG_MAX 0xFF + +enum { + REG_GP_ENM_BIT = 0, + REG_GP_ENS_BIT, + REG_GP_UNI_BIT, + REG_GP_RMP0_BIT, + REG_GP_RMP1_BIT, + REG_GP_OLED_BIT, +}; + +struct lm3509_bl { + struct regmap *regmap; + struct backlight_device *bl_main; + struct backlight_device *bl_sub; + struct gpio_desc *reset_gpio; +}; + +struct lm3509_bl_led_data { + const char *label; + int led_sources; + u32 brightness; + u32 max_brightness; +}; + +static void lm3509_reset(struct lm3509_bl *data) +{ + if (data->reset_gpio) { + gpiod_set_value(data->reset_gpio, 1); + udelay(1); + gpiod_set_value(data->reset_gpio, 0); + udelay(10); + } +} + +static int lm3509_update_status(struct backlight_device *bl, + unsigned int en_mask, unsigned int br_reg) +{ + struct lm3509_bl *data = bl_get_data(bl); + int ret; + bool en; + + ret = regmap_write(data->regmap, br_reg, backlight_get_brightness(bl)); + if (ret < 0) + return ret; + + en = !backlight_is_blank(bl); + return regmap_update_bits(data->regmap, REG_GP, en_mask, + en ? en_mask : 0); +} + +static int lm3509_main_update_status(struct backlight_device *bl) +{ + return lm3509_update_status(bl, BIT(REG_GP_ENM_BIT), REG_BMAIN); +} + +static const struct backlight_ops lm3509_main_ops = { + .options = BL_CORE_SUSPENDRESUME, + .update_status = lm3509_main_update_status, +}; + +static int lm3509_sub_update_status(struct backlight_device *bl) +{ + return lm3509_update_status(bl, BIT(REG_GP_ENS_BIT), REG_BSUB); +} + +static const struct backlight_ops lm3509_sub_ops = { + .options = BL_CORE_SUSPENDRESUME, + .update_status = lm3509_sub_update_status, +}; + +static struct backlight_device * +lm3509_backlight_register(struct device *dev, const char *name_suffix, + struct lm3509_bl *data, + const struct backlight_ops *ops, + const struct lm3509_bl_led_data *led_data) + +{ + struct backlight_device *bd; + struct backlight_properties props; + const char *label = led_data->label; + char name[64]; + + memset(&props, 0, sizeof(props)); + props.type = BACKLIGHT_RAW; + props.brightness = led_data->brightness; + props.max_brightness = led_data->max_brightness; + props.scale = BACKLIGHT_SCALE_NON_LINEAR; + + if (!label) { + snprintf(name, sizeof(name), "lm3509-%s-%s", dev_name(dev), + name_suffix); + label = name; + } + + bd = devm_backlight_device_register(dev, label, dev, data, ops, &props); + if (bd) + backlight_update_status(bd); + + return bd; +} + +static const struct regmap_config lm3509_regmap = { + .reg_bits = 8, + .val_bits = 8, + .max_register = REG_MAX, +}; + +static int lm3509_parse_led_sources(struct device_node *node, + int default_led_sources) +{ + u32 sources[LM3509_NUM_SINKS]; + int ret, num_sources, i; + + num_sources = of_property_count_u32_elems(node, "led-sources"); + if (num_sources < 0) + return default_led_sources; + else if (num_sources > ARRAY_SIZE(sources)) + return -EINVAL; + + ret = of_property_read_u32_array(node, "led-sources", sources, + num_sources); + if (ret) + return ret; + + for (i = 0; i < num_sources; i++) { + if (sources[i] >= LM3509_NUM_SINKS) + return -EINVAL; + + ret |= BIT(sources[i]); + } + + return ret; +} + +static int lm3509_parse_dt_node(struct device *dev, + struct lm3509_bl_led_data *led_data) +{ + struct device_node *child; + int seen_led_sources = 0; + + for_each_child_of_node(dev->of_node, child) { + struct lm3509_bl_led_data *ld; + int ret; + u32 reg; + int valid_led_sources; + + ret = of_property_read_u32(child, "reg", ®); + if (ret < 0) + return ret; + if (reg >= LM3509_NUM_SINKS) + return -EINVAL; + ld = &led_data[reg]; + + ld->led_sources = lm3509_parse_led_sources(child, BIT(reg)); + if (ld->led_sources < 0) + return ld->led_sources; + + if (reg == 0) + valid_led_sources = BIT(LM3509_SINK_MAIN) | + BIT(LM3509_SINK_SUB); + else + valid_led_sources = BIT(LM3509_SINK_SUB); + + if (ld->led_sources != (ld->led_sources & valid_led_sources)) + return -EINVAL; + + if (seen_led_sources & ld->led_sources) + return -EINVAL; + + seen_led_sources |= ld->led_sources; + + ld->label = NULL; + of_property_read_string(child, "label", &ld->label); + + ld->max_brightness = LM3509_MAX_BRIGHTNESS; + of_property_read_u32(child, "max-brightness", + &ld->max_brightness); + ld->max_brightness = + min_t(u32, ld->max_brightness, LM3509_MAX_BRIGHTNESS); + + ld->brightness = LM3509_DEF_BRIGHTNESS; + of_property_read_u32(child, "default-brightness", + &ld->brightness); + ld->brightness = min_t(u32, ld->brightness, ld->max_brightness); + } + + return 0; +} + +static int lm3509_probe(struct i2c_client *client) +{ + struct lm3509_bl *data; + struct device *dev = &client->dev; + int ret; + bool oled_mode = false; + unsigned int reg_gp_val = 0; + struct lm3509_bl_led_data led_data[LM3509_NUM_SINKS]; + u32 rate_of_change = 0; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + dev_err(dev, "i2c functionality check failed\n"); + return -EOPNOTSUPP; + } + + data = devm_kzalloc(dev, sizeof(struct lm3509_bl), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->regmap = devm_regmap_init_i2c(client, &lm3509_regmap); + if (IS_ERR(data->regmap)) + return PTR_ERR(data->regmap); + i2c_set_clientdata(client, data); + + data->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW); + if (IS_ERR(data->reset_gpio)) + return dev_err_probe(dev, PTR_ERR(data->reset_gpio), + "Failed to get 'reset' gpio\n"); + + lm3509_reset(data); + + memset(led_data, 0, sizeof(led_data)); + ret = lm3509_parse_dt_node(dev, led_data); + if (ret) + return ret; + + oled_mode = of_property_read_bool(dev->of_node, "ti,oled-mode"); + + if (!of_property_read_u32(dev->of_node, + "ti,brightness-rate-of-change-us", + &rate_of_change)) { + switch (rate_of_change) { + case 51: + reg_gp_val = 0; + break; + case 13000: + reg_gp_val = BIT(REG_GP_RMP1_BIT); + break; + case 26000: + reg_gp_val = BIT(REG_GP_RMP0_BIT); + break; + case 52000: + reg_gp_val = BIT(REG_GP_RMP0_BIT) | + BIT(REG_GP_RMP1_BIT); + break; + default: + dev_warn(dev, "invalid rate of change %u\n", + rate_of_change); + break; + } + } + + if (led_data[0].led_sources == + (BIT(LM3509_SINK_MAIN) | BIT(LM3509_SINK_SUB))) + reg_gp_val |= BIT(REG_GP_UNI_BIT); + if (oled_mode) + reg_gp_val |= BIT(REG_GP_OLED_BIT); + + ret = regmap_write(data->regmap, REG_GP, reg_gp_val); + if (ret < 0) + return dev_err_probe(dev, ret, "failed to write register\n"); + + if (led_data[0].led_sources) { + data->bl_main = lm3509_backlight_register( + dev, "main", data, &lm3509_main_ops, &led_data[0]); + if (IS_ERR(data->bl_main)) { + return dev_err_probe( + dev, PTR_ERR(data->bl_main), + "failed to register main backlight\n"); + } + } + + if (led_data[1].led_sources) { + data->bl_sub = lm3509_backlight_register( + dev, "sub", data, &lm3509_sub_ops, &led_data[1]); + if (IS_ERR(data->bl_sub)) { + return dev_err_probe( + dev, PTR_ERR(data->bl_sub), + "failed to register secondary backlight\n"); + } + } + + return 0; +} + +static void lm3509_remove(struct i2c_client *client) +{ + struct lm3509_bl *data = i2c_get_clientdata(client); + + regmap_write(data->regmap, REG_GP, 0x00); +} + +static const struct i2c_device_id lm3509_id[] = { { LM3509_NAME, 0 }, {} }; + +MODULE_DEVICE_TABLE(i2c, lm3509_id); + +static const struct of_device_id lm3509_match_table[] = { + { + .compatible = "ti,lm3509", + }, + {}, +}; + +MODULE_DEVICE_TABLE(of, lm3509_match_table); + +static struct i2c_driver lm3509_i2c_driver = { + .driver = { + .name = LM3509_NAME, + .of_match_table = lm3509_match_table, + }, + .probe = lm3509_probe, + .remove = lm3509_remove, + .id_table = lm3509_id, +}; + +module_i2c_driver(lm3509_i2c_driver); + +MODULE_DESCRIPTION("Texas Instruments Backlight driver for LM3509"); +MODULE_AUTHOR("Patrick Gansterer <paroga@xxxxxxxxxx>"); +MODULE_LICENSE("GPL"); -- 2.44.0
