diff options
Diffstat (limited to 'drivers/leds/leds-lm3697.c')
| -rw-r--r-- | drivers/leds/leds-lm3697.c | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/drivers/leds/leds-lm3697.c b/drivers/leds/leds-lm3697.c new file mode 100644 index 0000000000..cfb8ac220d --- /dev/null +++ b/drivers/leds/leds-lm3697.c @@ -0,0 +1,387 @@ +// SPDX-License-Identifier: GPL-2.0 +// TI LM3697 LED chip family driver +// Copyright (C) 2018 Texas Instruments Incorporated - https://www.ti.com/ + +#include <linux/bits.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/property.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> +#include <linux/types.h> + +#include <linux/leds-ti-lmu-common.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_MAX_CONTROL_BANKS 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 + * @lmu_data: Register and setting values for common code + * @control_bank: Control bank the LED is associated to. 0 is control bank A + * 1 is control bank B + * @enabled: LED brightness level (or LED_OFF) + * @num_leds: Number of LEDs available + */ +struct lm3697_led { + u32 hvled_strings[LM3697_MAX_LED_STRINGS]; + char label[LED_MAX_NAME_SIZE]; + struct led_classdev led_dev; + struct lm3697 *priv; + struct ti_lmu_bank lmu_data; + int control_bank; + int enabled; + int num_leds; +}; + +/** + * 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 + * @bank_cfg: OUTPUT_CONFIG register values + * @num_banks: Number of control banks + */ +struct lm3697 { + struct gpio_desc *enable_gpio; + struct regulator *regulator; + struct i2c_client *client; + struct regmap *regmap; + struct device *dev; + struct mutex lock; + + int bank_cfg; + int num_banks; + + 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 ctrl_en_val = (1 << led->control_bank); + struct device *dev = led->priv->dev; + int ret; + + mutex_lock(&led->priv->lock); + + if (brt_val == LED_OFF) { + ret = regmap_update_bits(led->priv->regmap, LM3697_CTRL_ENABLE, + ctrl_en_val, ~ctrl_en_val); + if (ret) { + dev_err(dev, "Cannot write ctrl register\n"); + goto brightness_out; + } + + led->enabled = LED_OFF; + } else { + ret = ti_lmu_common_set_brightness(&led->lmu_data, brt_val); + if (ret) { + dev_err(dev, "Cannot write brightness\n"); + goto brightness_out; + } + + if (!led->enabled) { + ret = regmap_update_bits(led->priv->regmap, + LM3697_CTRL_ENABLE, + ctrl_en_val, ctrl_en_val); + if (ret) { + dev_err(dev, "Cannot enable the device\n"); + goto brightness_out; + } + + led->enabled = brt_val; + } + } + +brightness_out: + mutex_unlock(&led->priv->lock); + return ret; +} + +static int lm3697_init(struct lm3697 *priv) +{ + struct device *dev = priv->dev; + struct lm3697_led *led; + int i, 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(dev, "Cannot reset the device\n"); + goto out; + } + } + + ret = regmap_write(priv->regmap, LM3697_CTRL_ENABLE, 0x0); + if (ret) { + dev_err(dev, "Cannot write ctrl enable\n"); + goto out; + } + + ret = regmap_write(priv->regmap, LM3697_OUTPUT_CONFIG, priv->bank_cfg); + if (ret) + dev_err(dev, "Cannot write OUTPUT config\n"); + + for (i = 0; i < priv->num_banks; i++) { + led = &priv->leds[i]; + ret = ti_lmu_common_set_ramp(&led->lmu_data); + if (ret) + dev_err(dev, "Setting the ramp rate failed\n"); + } +out: + return ret; +} + +static int lm3697_probe_dt(struct lm3697 *priv) +{ + struct fwnode_handle *child = NULL; + struct device *dev = priv->dev; + struct lm3697_led *led; + int ret = -EINVAL; + int control_bank; + size_t i = 0; + int j; + + priv->enable_gpio = devm_gpiod_get_optional(dev, "enable", + GPIOD_OUT_LOW); + if (IS_ERR(priv->enable_gpio)) + return dev_err_probe(dev, PTR_ERR(priv->enable_gpio), + "Failed to get enable GPIO\n"); + + priv->regulator = devm_regulator_get(dev, "vled"); + if (IS_ERR(priv->regulator)) + priv->regulator = NULL; + + device_for_each_child_node(dev, child) { + struct led_init_data init_data = {}; + + ret = fwnode_property_read_u32(child, "reg", &control_bank); + if (ret) { + dev_err(dev, "reg property missing\n"); + goto child_out; + } + + if (control_bank > LM3697_CONTROL_B) { + dev_err(dev, "reg property is invalid\n"); + ret = -EINVAL; + goto child_out; + } + + led = &priv->leds[i]; + + ret = ti_lmu_common_get_brt_res(dev, child, &led->lmu_data); + if (ret) + dev_warn(dev, + "brightness resolution property missing\n"); + + led->control_bank = control_bank; + led->lmu_data.regmap = priv->regmap; + led->lmu_data.runtime_ramp_reg = LM3697_CTRL_A_RAMP + + control_bank; + led->lmu_data.msb_brightness_reg = LM3697_CTRL_A_BRT_MSB + + led->control_bank * 2; + led->lmu_data.lsb_brightness_reg = LM3697_CTRL_A_BRT_LSB + + led->control_bank * 2; + + led->num_leds = fwnode_property_count_u32(child, "led-sources"); + if (led->num_leds > LM3697_MAX_LED_STRINGS) { + dev_err(dev, "Too many LED strings defined\n"); + continue; + } + + ret = fwnode_property_read_u32_array(child, "led-sources", + led->hvled_strings, + led->num_leds); + if (ret) { + dev_err(dev, "led-sources property missing\n"); + goto child_out; + } + + for (j = 0; j < led->num_leds; j++) + priv->bank_cfg |= + (led->control_bank << led->hvled_strings[j]); + + ret = ti_lmu_common_get_ramp_params(dev, child, &led->lmu_data); + if (ret) + dev_warn(dev, "runtime-ramp properties missing\n"); + + init_data.fwnode = child; + init_data.devicename = priv->client->name; + /* for backwards compatibility if `label` is not present */ + init_data.default_label = ":"; + + led->priv = priv; + led->led_dev.max_brightness = led->lmu_data.max_brightness; + led->led_dev.brightness_set_blocking = lm3697_brightness_set; + + ret = devm_led_classdev_register_ext(dev, &led->led_dev, + &init_data); + if (ret) { + dev_err(dev, "led register err: %d\n", ret); + goto child_out; + } + + i++; + } + + return ret; + +child_out: + fwnode_handle_put(child); + return ret; +} + +static int lm3697_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct lm3697 *led; + int count; + int ret; + + count = device_get_child_node_count(dev); + if (!count || count > LM3697_MAX_CONTROL_BANKS) { + dev_err(dev, "Strange device tree!"); + return -ENODEV; + } + + led = devm_kzalloc(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 = dev; + led->num_banks = count; + led->regmap = devm_regmap_init_i2c(client, &lm3697_regmap_config); + if (IS_ERR(led->regmap)) { + ret = PTR_ERR(led->regmap); + dev_err(dev, "Failed to allocate register map: %d\n", ret); + return ret; + } + + ret = lm3697_probe_dt(led); + if (ret) + return ret; + + return lm3697_init(led); +} + +static void lm3697_remove(struct i2c_client *client) +{ + struct lm3697 *led = i2c_get_clientdata(client); + struct device *dev = &led->client->dev; + int ret; + + ret = regmap_update_bits(led->regmap, LM3697_CTRL_ENABLE, + LM3697_CTRL_A_B_EN, 0); + if (ret) + dev_err(dev, "Failed to disable the device\n"); + + if (led->enable_gpio) + gpiod_direction_output(led->enable_gpio, 0); + + if (led->regulator) { + ret = regulator_disable(led->regulator); + if (ret) + dev_err(dev, "Failed to disable regulator\n"); + } + + mutex_destroy(&led->lock); +} + +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@ti.com>"); +MODULE_LICENSE("GPL v2"); |