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 <par...@paroga.com>
---
drivers/video/backlight/Kconfig | 7 +
drivers/video/backlight/Makefile | 1 +
drivers/video/backlight/lm3509_bl.c | 247 ++++++++++++++++++++++++++++
3 files changed, 255 insertions(+)
create mode 100644 drivers/video/backlight/lm3509_bl.c
diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index ea2d0d69bd8c..96ad5dc584b6 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -366,6 +366,13 @@ 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 06966cb20459..51a4ac5d0530 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_BACKLIGHT_HP700) += jornada720_bl.o
obj-$(CONFIG_BACKLIGHT_IPAQ_MICRO) += ipaq_micro_bl.o
obj-$(CONFIG_BACKLIGHT_KTD253) += ktd253-backlight.o
obj-$(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..977145374641
--- /dev/null
+++ b/drivers/video/backlight/lm3509_bl.c
@@ -0,0 +1,247 @@
+// 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_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;
+};
+
+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, bl->props.brightness);
+ if (ret < 0)
+ return ret;
+
+ en = bl->props.power <= FB_BLANK_NORMAL;
+ 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, int brightness, int max_brightness)
+
+{
+ struct backlight_device *bd;
+ struct backlight_properties props;
+ char name[64];
+
+ memset(&props, 0, sizeof(props));
+ props.type = BACKLIGHT_RAW;
+ props.brightness = brightness;
+ props.max_brightness = max_brightness;
+ props.power = brightness > 0 ? FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN;
+
+ snprintf(name, sizeof(name), "lm3509-%s-%s", dev_name(dev),
+ name_suffix);
+
+ bd = devm_backlight_device_register(dev, name, 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_probe(struct i2c_client *client)
+{
+ struct lm3509_bl *data;
+ struct device *dev = &client->dev;
+ int ret;
+ bool unison_mode = false;
+ bool oled_mode = false;
+ unsigned int reg_gp_val = 0;
+ u32 rate_of_change = 0;
+ u32 brightness = LM3509_DEF_BRIGHTNESS;
+ u32 max_brightness = LM3509_MAX_BRIGHTNESS;
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ dev_err(dev, "fail : i2c functionality check\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)) {
+ dev_err(dev, "fail : allocate register map\n");
+ 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)) {
+ ret = PTR_ERR(data->reset_gpio);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "fail : get reset GPIO: %d\n", ret);
+ return ret;
+ }
+
+ lm3509_reset(data);
+
+ of_property_read_u32(dev->of_node, "default-brightness", &brightness);
+ of_property_read_u32(dev->of_node, "max-brightness", &max_brightness);
+ unison_mode = of_property_read_bool(dev->of_node, "ti,unison-mode");
+ 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 (unison_mode)
+ 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 ret;
+
+ max_brightness = min_t(u32, max_brightness, LM3509_MAX_BRIGHTNESS);
+ brightness = min_t(u32, brightness, max_brightness);
+
+ data->bl_main = lm3509_backlight_register(dev, "main", data,
+ &lm3509_main_ops, brightness,
+ max_brightness);
+ if (IS_ERR(data->bl_main)) {
+ dev_err(dev, "fail : register main backlight\n");
+ return PTR_ERR(data->bl_main);
+ }
+
+ if (!unison_mode) {
+ data->bl_sub = lm3509_backlight_register(dev, "sub", data,
+ &lm3509_sub_ops,
+ brightness,
+ max_brightness);
+ if (IS_ERR(data->bl_sub)) {
+ dev_err(dev, "fail : register secondary backlight\n");
+ return PTR_ERR(data->bl_sub);
+ }
+ }
+
+ 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 <par...@paroga.com>");
+MODULE_LICENSE("GPL");
--
2.44.0
