Introduce the lm3697 LED driver for backlighting and display. Datasheet location: http://www.ti.com/lit/ds/symlink/lm3697.pdf Signed-off-by: Dan Murphy <dmurphy@xxxxxx> --- v3 - Add code to support led-sources and control bank configuration also fix other miscellaneous issues reported- https://lore.kernel.org/patchwork/patch/972336/ v2 - Removed unneed 'of' calls in dt_parse, fixed comment, fixed checkpatch error, and change led registration - https://lore.kernel.org/patchwork/patch/971327/ drivers/leds/Kconfig | 9 + drivers/leds/Makefile | 1 + drivers/leds/leds-lm3697.c | 403 +++++++++++++++++++++++++++++++++++++ 3 files changed, 413 insertions(+) create mode 100644 drivers/leds/leds-lm3697.c diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 44097a3e0fcc..784cbe375724 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -151,6 +151,15 @@ config LEDS_LM3642 converter plus 1.5A constant current driver for a high-current white LED. +config LEDS_LM3697 + tristate "LED support for LM3697 Chip" + depends on LEDS_CLASS && I2C + select REGMAP_I2C + help + This option enables support for LEDs connected to LM3697. + The LM3697 is an 11 bit high performance backlight driver for + keypad and display lighting. + config LEDS_LM3692X tristate "LED support for LM3692x Chips" depends on LEDS_CLASS && I2C && OF diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 420b5d2cfa62..2813f089f3db 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_LEDS_LOCOMO) += leds-locomo.o obj-$(CONFIG_LEDS_LM3530) += leds-lm3530.o obj-$(CONFIG_LEDS_LM3533) += leds-lm3533.o obj-$(CONFIG_LEDS_LM3642) += leds-lm3642.o +obj-$(CONFIG_LEDS_LM3697) += leds-lm3697.o obj-$(CONFIG_LEDS_MIKROTIK_RB532) += leds-rb532.o obj-$(CONFIG_LEDS_S3C24XX) += leds-s3c24xx.o obj-$(CONFIG_LEDS_NET48XX) += leds-net48xx.o diff --git a/drivers/leds/leds-lm3697.c b/drivers/leds/leds-lm3697.c new file mode 100644 index 000000000000..33205040c4f9 --- /dev/null +++ b/drivers/leds/leds-lm3697.c @@ -0,0 +1,403 @@ +// SPDX-License-Identifier: GPL-2.0 +// TI LM3697 LED chip family driver +// Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/ + +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/leds.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> +#include <linux/slab.h> +#include <uapi/linux/uleds.h> + +#define LM3697_REV 0x0 +#define LM3697_RESET 0x1 +#define LM3697_OUTPUT_CONFIG 0x10 +#define LM3697_CTRL_A_RAMP 0x11 +#define LM3697_CTRL_B_RAMP 0x12 +#define LM3697_CTRL_A_B_RT_RAMP 0x13 +#define LM3697_CTRL_A_B_RAMP_CFG 0x14 +#define LM3697_CTRL_A_B_BRT_CFG 0x16 +#define LM3697_CTRL_A_FS_CURR_CFG 0x17 +#define LM3697_CTRL_B_FS_CURR_CFG 0x18 +#define LM3697_PWM_CFG 0x1c +#define LM3697_CTRL_A_BRT_LSB 0x20 +#define LM3697_CTRL_A_BRT_MSB 0x21 +#define LM3697_CTRL_B_BRT_LSB 0x22 +#define LM3697_CTRL_B_BRT_MSB 0x23 +#define LM3697_CTRL_ENABLE 0x24 + +#define LM3697_SW_RESET BIT(0) + +#define LM3697_CTRL_A_EN BIT(0) +#define LM3697_CTRL_B_EN BIT(1) +#define LM3697_CTRL_A_B_EN (LM3697_CTRL_A_EN | LM3697_CTRL_B_EN) + +#define LM3697_MAX_LED_STRINGS 3 + +#define LM3697_CONTROL_A 0 +#define LM3697_CONTROL_B 1 + +#define LM3697_END_OF_ARRAY 0 +#define LM3697_HVLED1 1 +#define LM3697_HVLED2 2 +#define LM3697_HVLED3 3 + +#define LM3697_HVLED1_SHIFT 0 +#define LM3697_HVLED2_SHIFT 1 +#define LM3697_HVLED3_SHIFT 2 + +/** + * struct lm3697_led - + * @hvled_strings - Array of LED strings associated with a control bank + * @label - LED label + * @led_dev - LED class device + * @priv - Pointer to the device struct + * @control_bank - Control bank the LED is associated to. 0 is control bank A + * 1 is control bank B. + */ +struct lm3697_led { + u32 hvled_strings[LM3697_MAX_LED_STRINGS]; + char label[LED_MAX_NAME_SIZE]; + struct led_classdev led_dev; + struct lm3697 *priv; + int control_bank; +}; + +/** + * struct lm3697 - + * @enable_gpio - Hardware enable gpio + * @regulator - LED supply regulator pointer + * @client - Pointer to the I2C client + * @regmap - Devices register map + * @dev - Pointer to the devices device struct + * @lock - Lock for reading/writing the device + * @leds - Array of LED strings. + */ +struct lm3697 { + struct gpio_desc *enable_gpio; + struct regulator *regulator; + struct i2c_client *client; + struct regmap *regmap; + struct device *dev; + struct mutex lock; + struct lm3697_led leds[]; +}; + +static const struct reg_default lm3697_reg_defs[] = { + {LM3697_OUTPUT_CONFIG, 0x6}, + {LM3697_CTRL_A_RAMP, 0x0}, + {LM3697_CTRL_B_RAMP, 0x0}, + {LM3697_CTRL_A_B_RT_RAMP, 0x0}, + {LM3697_CTRL_A_B_RAMP_CFG, 0x0}, + {LM3697_CTRL_A_B_BRT_CFG, 0x0}, + {LM3697_CTRL_A_FS_CURR_CFG, 0x13}, + {LM3697_CTRL_B_FS_CURR_CFG, 0x13}, + {LM3697_PWM_CFG, 0xc}, + {LM3697_CTRL_A_BRT_LSB, 0x0}, + {LM3697_CTRL_A_BRT_MSB, 0x0}, + {LM3697_CTRL_B_BRT_LSB, 0x0}, + {LM3697_CTRL_B_BRT_MSB, 0x0}, + {LM3697_CTRL_ENABLE, 0x0}, +}; + +static const struct regmap_config lm3697_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + + .max_register = LM3697_CTRL_ENABLE, + .reg_defaults = lm3697_reg_defs, + .num_reg_defaults = ARRAY_SIZE(lm3697_reg_defs), + .cache_type = REGCACHE_FLAT, +}; + +static int lm3697_brightness_set(struct led_classdev *led_cdev, + enum led_brightness brt_val) +{ + struct lm3697_led *led = container_of(led_cdev, struct lm3697_led, + led_dev); + int brt_msb_reg, brt_lsb_reg, ctrl_en_val; + int led_brightness_lsb = (brt_val >> 5); + int ret; + + mutex_lock(&led->priv->lock); + + if (led->control_bank == LM3697_CONTROL_A) { + brt_msb_reg = LM3697_CTRL_A_BRT_MSB; + brt_lsb_reg = LM3697_CTRL_A_BRT_LSB; + ctrl_en_val = LM3697_CTRL_A_EN; + } else { + brt_msb_reg = LM3697_CTRL_B_BRT_MSB; + brt_lsb_reg = LM3697_CTRL_B_BRT_LSB; + ctrl_en_val = LM3697_CTRL_B_EN; + } + + if (brt_val == LED_OFF) + ret = regmap_update_bits(led->priv->regmap, LM3697_CTRL_ENABLE, + ctrl_en_val, ~ctrl_en_val); + else + ret = regmap_update_bits(led->priv->regmap, LM3697_CTRL_ENABLE, + ctrl_en_val, ctrl_en_val); + + if (ret) { + dev_err(&led->priv->client->dev, "Cannot write CTRL enable\n"); + goto out; + } + + ret = regmap_write(led->priv->regmap, brt_lsb_reg, led_brightness_lsb); + if (ret) { + dev_err(&led->priv->client->dev, "Cannot write LSB\n"); + goto out; + } + + ret = regmap_write(led->priv->regmap, brt_msb_reg, brt_val); + if (ret) { + dev_err(&led->priv->client->dev, "Cannot write MSB\n"); + goto out; + } +out: + mutex_unlock(&led->priv->lock); + return ret; +} + +static int lm3697_set_control_bank(struct lm3697 *priv) +{ + u8 control_bank_config = 0; + struct lm3697_led *led; + int ret, i; + + led = &priv->leds[0]; + if (led->control_bank == LM3697_CONTROL_A) + led = &priv->leds[1]; + + if (led->control_bank == LM3697_CONTROL_B && + led->hvled_strings[0] == LM3697_END_OF_ARRAY) + goto write_config; + + for (i = 0; i < LM3697_MAX_LED_STRINGS; i++) { + if (led->hvled_strings[i] == LM3697_END_OF_ARRAY) + break; + + if (led->hvled_strings[i] == LM3697_HVLED1) + control_bank_config |= 1 << LM3697_HVLED1_SHIFT; + + if (led->hvled_strings[i] == LM3697_HVLED2) + control_bank_config |= 1 << LM3697_HVLED2_SHIFT; + + if (led->hvled_strings[i] == LM3697_HVLED3) + control_bank_config |= 1 << LM3697_HVLED3_SHIFT; + } + +write_config: + ret = regmap_write(priv->regmap, LM3697_OUTPUT_CONFIG, + control_bank_config); + if (ret) + dev_err(&priv->client->dev, "Cannot write OUTPUT config\n"); + + return ret; +} + +static int lm3697_init(struct lm3697 *priv) +{ + int ret; + + if (priv->enable_gpio) { + gpiod_direction_output(priv->enable_gpio, 1); + } else { + ret = regmap_write(priv->regmap, LM3697_RESET, LM3697_SW_RESET); + if (ret) { + dev_err(&priv->client->dev, "Cannot reset the device\n"); + goto out; + } + } + + ret = regmap_write(priv->regmap, LM3697_CTRL_ENABLE, 0x0); + if (ret) { + dev_err(&priv->client->dev, "Cannot write ctrl enable\n"); + goto out; + } + + ret = lm3697_set_control_bank(priv); + if (ret) + dev_err(&priv->client->dev, "Setting the CRTL bank failed\n"); + +out: + return ret; +} + +static int lm3697_probe_dt(struct lm3697 *priv) +{ + struct fwnode_handle *child = NULL; + struct lm3697_led *led; + const char *name; + int control_bank; + size_t i = 0; + int ret; + + priv->enable_gpio = devm_gpiod_get_optional(&priv->client->dev, + "enable", GPIOD_OUT_LOW); + if (IS_ERR(priv->enable_gpio)) { + ret = PTR_ERR(priv->enable_gpio); + dev_err(&priv->client->dev, "Failed to get enable gpio: %d\n", + ret); + return ret; + } + + priv->regulator = devm_regulator_get(&priv->client->dev, "vled"); + if (IS_ERR(priv->regulator)) + priv->regulator = NULL; + + device_for_each_child_node(priv->dev, child) { + ret = fwnode_property_read_u32(child, "reg", &control_bank); + if (ret) { + dev_err(&priv->client->dev, "reg property missing\n"); + fwnode_handle_put(child); + goto child_out; + } + + if (control_bank > LM3697_CONTROL_B) { + dev_err(&priv->client->dev, "reg property is invalid\n"); + ret = -EINVAL; + fwnode_handle_put(child); + goto child_out; + } + + led = &priv->leds[i]; + led->control_bank = control_bank; + ret = fwnode_property_read_u32_array(child, "led-sources", + led->hvled_strings, + LM3697_MAX_LED_STRINGS); + if (ret) { + dev_err(&priv->client->dev, "led-sources property missing\n"); + fwnode_handle_put(child); + goto child_out; + } + + fwnode_property_read_string(child, "linux,default-trigger", + &led->led_dev.default_trigger); + + ret = fwnode_property_read_string(child, "label", &name); + if (ret) + snprintf(led->label, sizeof(led->label), + "%s::", priv->client->name); + else + snprintf(led->label, sizeof(led->label), + "%s:%s", priv->client->name, name); + + led->priv = priv; + led->led_dev.name = led->label; + led->led_dev.brightness_set_blocking = lm3697_brightness_set; + + ret = devm_led_classdev_register(priv->dev, &led->led_dev); + if (ret) { + dev_err(&priv->client->dev, "led register err: %d\n", + ret); + fwnode_handle_put(child); + goto child_out; + } + + i++; + } + +child_out: + return ret; +} + +static int lm3697_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct lm3697 *led; + int count; + int ret; + + count = device_get_child_node_count(&client->dev); + if (!count) { + dev_err(&client->dev, "LEDs are not defined in device tree!"); + return -ENODEV; + } + + led = devm_kzalloc(&client->dev, struct_size(led, leds, count), + GFP_KERNEL); + if (!led) + return -ENOMEM; + + mutex_init(&led->lock); + i2c_set_clientdata(client, led); + + led->client = client; + led->dev = &client->dev; + led->regmap = devm_regmap_init_i2c(client, &lm3697_regmap_config); + if (IS_ERR(led->regmap)) { + ret = PTR_ERR(led->regmap); + dev_err(&client->dev, "Failed to allocate register map: %d\n", + ret); + return ret; + } + + ret = lm3697_probe_dt(led); + if (ret) + return ret; + + ret = lm3697_init(led); + + return ret; +} + +static int lm3697_remove(struct i2c_client *client) +{ + struct lm3697 *led = i2c_get_clientdata(client); + int ret; + + ret = regmap_update_bits(led->regmap, LM3697_CTRL_ENABLE, + LM3697_CTRL_A_B_EN, 0); + if (ret) { + dev_err(&led->client->dev, "Failed to disable the device\n"); + return ret; + } + + if (led->enable_gpio) + gpiod_direction_output(led->enable_gpio, 0); + + if (led->regulator) { + ret = regulator_disable(led->regulator); + if (ret) + dev_err(&led->client->dev, + "Failed to disable regulator\n"); + } + + mutex_destroy(&led->lock); + + return 0; +} + +static const struct i2c_device_id lm3697_id[] = { + { "lm3697", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, lm3697_id); + +static const struct of_device_id of_lm3697_leds_match[] = { + { .compatible = "ti,lm3697", }, + {}, +}; +MODULE_DEVICE_TABLE(of, of_lm3697_leds_match); + +static struct i2c_driver lm3697_driver = { + .driver = { + .name = "lm3697", + .of_match_table = of_lm3697_leds_match, + }, + .probe = lm3697_probe, + .remove = lm3697_remove, + .id_table = lm3697_id, +}; +module_i2c_driver(lm3697_driver); + +MODULE_DESCRIPTION("Texas Instruments LM3697 LED driver"); +MODULE_AUTHOR("Dan Murphy <dmurphy@xxxxxx>"); +MODULE_LICENSE("GPL v2"); -- 2.17.0.582.gccdcbd54c
