diff options
Diffstat (limited to 'drivers/leds/leds-lm3532.c')
-rw-r--r-- | drivers/leds/leds-lm3532.c | 683 |
1 files changed, 683 insertions, 0 deletions
diff --git a/drivers/leds/leds-lm3532.c b/drivers/leds/leds-lm3532.c new file mode 100644 index 000000000000..180895b83b88 --- /dev/null +++ b/drivers/leds/leds-lm3532.c @@ -0,0 +1,683 @@ +// SPDX-License-Identifier: GPL-2.0 +// TI LM3532 LED driver +// Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/ + +#include <linux/i2c.h> +#include <linux/leds.h> +#include <linux/slab.h> +#include <linux/regmap.h> +#include <linux/types.h> +#include <linux/regulator/consumer.h> +#include <linux/module.h> +#include <uapi/linux/uleds.h> +#include <linux/gpio/consumer.h> + +#define LM3532_NAME "lm3532-led" +#define LM3532_BL_MODE_MANUAL 0x00 +#define LM3532_BL_MODE_ALS 0x01 + +#define LM3532_REG_OUTPUT_CFG 0x10 +#define LM3532_REG_STARTSHUT_RAMP 0x11 +#define LM3532_REG_RT_RAMP 0x12 +#define LM3532_REG_PWM_A_CFG 0x13 +#define LM3532_REG_PWM_B_CFG 0x14 +#define LM3532_REG_PWM_C_CFG 0x15 +#define LM3532_REG_ZONE_CFG_A 0x16 +#define LM3532_REG_CTRL_A_BRT 0x17 +#define LM3532_REG_ZONE_CFG_B 0x18 +#define LM3532_REG_CTRL_B_BRT 0x19 +#define LM3532_REG_ZONE_CFG_C 0x1a +#define LM3532_REG_CTRL_C_BRT 0x1b +#define LM3532_REG_ENABLE 0x1d +#define LM3532_ALS_CONFIG 0x23 +#define LM3532_REG_ZN_0_HI 0x60 +#define LM3532_REG_ZN_0_LO 0x61 +#define LM3532_REG_ZN_1_HI 0x62 +#define LM3532_REG_ZN_1_LO 0x63 +#define LM3532_REG_ZN_2_HI 0x64 +#define LM3532_REG_ZN_2_LO 0x65 +#define LM3532_REG_ZN_3_HI 0x66 +#define LM3532_REG_ZN_3_LO 0x67 +#define LM3532_REG_MAX 0x7e + +/* Contorl Enable */ +#define LM3532_CTRL_A_ENABLE BIT(0) +#define LM3532_CTRL_B_ENABLE BIT(1) +#define LM3532_CTRL_C_ENABLE BIT(2) + +/* PWM Zone Control */ +#define LM3532_PWM_ZONE_MASK 0x7c +#define LM3532_PWM_ZONE_0_EN BIT(2) +#define LM3532_PWM_ZONE_1_EN BIT(3) +#define LM3532_PWM_ZONE_2_EN BIT(4) +#define LM3532_PWM_ZONE_3_EN BIT(5) +#define LM3532_PWM_ZONE_4_EN BIT(6) + +/* Brightness Configuration */ +#define LM3532_I2C_CTRL BIT(0) +#define LM3532_ALS_CTRL 0 +#define LM3532_LINEAR_MAP BIT(1) +#define LM3532_ZONE_MASK (BIT(2) | BIT(3) | BIT(4)) +#define LM3532_ZONE_0 0 +#define LM3532_ZONE_1 BIT(2) +#define LM3532_ZONE_2 BIT(3) +#define LM3532_ZONE_3 (BIT(2) | BIT(3)) +#define LM3532_ZONE_4 BIT(4) + +#define LM3532_ENABLE_ALS BIT(3) +#define LM3532_ALS_SEL_SHIFT 6 + +/* Zone Boundary Register */ +#define LM3532_ALS_WINDOW_mV 2000 +#define LM3532_ALS_ZB_MAX 4 +#define LM3532_ALS_OFFSET_mV 2 + +#define LM3532_CONTROL_A 0 +#define LM3532_CONTROL_B 1 +#define LM3532_CONTROL_C 2 +#define LM3532_MAX_CONTROL_BANKS 3 +#define LM3532_MAX_LED_STRINGS 3 + +#define LM3532_OUTPUT_CFG_MASK 0x3 +#define LM3532_BRT_VAL_ADJUST 8 +#define LM3532_RAMP_DOWN_SHIFT 3 + +#define LM3532_NUM_RAMP_VALS 8 +#define LM3532_NUM_AVG_VALS 8 +#define LM3532_NUM_IMP_VALS 32 + +/* + * struct lm3532_als_data + * @config - value of ALS configuration register + * @als1_imp_sel - value of ALS1 resistor select register + * @als2_imp_sel - value of ALS2 resistor select register + * @als_avrg_time - ALS averaging time + * @als_input_mode - ALS input mode for brightness control + * @als_vmin - Minimum ALS voltage + * @als_vmax - Maximum ALS voltage + * @zone_lo - values of ALS lo ZB(Zone Boundary) registers + * @zone_hi - values of ALS hi ZB(Zone Boundary) registers + */ +struct lm3532_als_data { + u8 config; + u8 als1_imp_sel; + u8 als2_imp_sel; + u8 als_avrg_time; + u8 als_input_mode; + u32 als_vmin; + u32 als_vmax; + u8 zones_lo[LM3532_ALS_ZB_MAX]; + u8 zones_hi[LM3532_ALS_ZB_MAX]; +}; + +/** + * struct lm3532_led + * @led_dev: led class device + * @priv - Pointer the device data structure + * @control_bank - Control bank the LED is associated to + * @mode - Mode of the LED string + * @num_leds - Number of LED strings are supported in this array + * @led_strings - The LED strings supported in this array + * @label - LED label + */ +struct lm3532_led { + struct led_classdev led_dev; + struct lm3532_data *priv; + + int control_bank; + int mode; + int num_leds; + u32 led_strings[LM3532_MAX_CONTROL_BANKS]; + char label[LED_MAX_NAME_SIZE]; +}; + +/** + * struct lm3532_data + * @enable_gpio - Hardware enable gpio + * @regulator: regulator + * @client: i2c client + * @regmap - Devices register map + * @dev - Pointer to the devices device struct + * @lock - Lock for reading/writing the device + * @als_data - Pointer to the als data struct + * @runtime_ramp_up - Runtime ramp up setting + * @runtime_ramp_down - Runtime ramp down setting + * @leds - Array of LED strings + */ +struct lm3532_data { + struct gpio_desc *enable_gpio; + struct regulator *regulator; + struct i2c_client *client; + struct regmap *regmap; + struct device *dev; + struct mutex lock; + + struct lm3532_als_data *als_data; + + u32 runtime_ramp_up; + u32 runtime_ramp_down; + + struct lm3532_led leds[]; +}; + +static const struct reg_default lm3532_reg_defs[] = { + {LM3532_REG_OUTPUT_CFG, 0xe4}, + {LM3532_REG_STARTSHUT_RAMP, 0xc0}, + {LM3532_REG_RT_RAMP, 0xc0}, + {LM3532_REG_PWM_A_CFG, 0x82}, + {LM3532_REG_PWM_B_CFG, 0x82}, + {LM3532_REG_PWM_C_CFG, 0x82}, + {LM3532_REG_ZONE_CFG_A, 0xf1}, + {LM3532_REG_CTRL_A_BRT, 0xf3}, + {LM3532_REG_ZONE_CFG_B, 0xf1}, + {LM3532_REG_CTRL_B_BRT, 0xf3}, + {LM3532_REG_ZONE_CFG_C, 0xf1}, + {LM3532_REG_CTRL_C_BRT, 0xf3}, + {LM3532_REG_ENABLE, 0xf8}, + {LM3532_ALS_CONFIG, 0x44}, + {LM3532_REG_ZN_0_HI, 0x35}, + {LM3532_REG_ZN_0_LO, 0x33}, + {LM3532_REG_ZN_1_HI, 0x6a}, + {LM3532_REG_ZN_1_LO, 0x66}, + {LM3532_REG_ZN_2_HI, 0xa1}, + {LM3532_REG_ZN_2_LO, 0x99}, + {LM3532_REG_ZN_3_HI, 0xdc}, + {LM3532_REG_ZN_3_LO, 0xcc}, +}; + +static const struct regmap_config lm3532_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + + .max_register = LM3532_REG_MAX, + .reg_defaults = lm3532_reg_defs, + .num_reg_defaults = ARRAY_SIZE(lm3532_reg_defs), + .cache_type = REGCACHE_FLAT, +}; + +const static int als_imp_table[LM3532_NUM_IMP_VALS] = {37000, 18500, 12330, + 92500, 7400, 6170, 5290, + 4630, 4110, 3700, 3360, + 3080, 2850, 2640, 2440, + 2310, 2180, 2060, 1950, + 1850, 1760, 1680, 1610, + 1540, 1480, 1420, 1370, + 1320, 1280, 1230, 1190}; +static int lm3532_get_als_imp_index(int als_imped) +{ + int i; + + if (als_imped > als_imp_table[1]) + return 0; + + if (als_imped < als_imp_table[LM3532_NUM_IMP_VALS - 1]) + return LM3532_NUM_IMP_VALS - 1; + + for (i = 1; i < LM3532_NUM_IMP_VALS; i++) { + if (als_imped == als_imp_table[i]) + return i; + + /* Find an approximate index by looking up the table */ + if (als_imped < als_imp_table[i - 1] && + als_imped > als_imp_table[i]) { + if (als_imped - als_imp_table[i - 1] < + als_imp_table[i] - als_imped) + return i + 1; + else + return i; + } + } + + return -EINVAL; +} + +static int lm3532_get_index(const int table[], int size, int value) +{ + int i; + + for (i = 1; i < size; i++) { + if (value == table[i]) + return i; + + /* Find an approximate index by looking up the table */ + if (value > table[i - 1] && + value < table[i]) { + if (value - table[i - 1] < table[i] - value) + return i - 1; + else + return i; + } + } + + return -EINVAL; +} + +const static int als_avrg_table[LM3532_NUM_AVG_VALS] = {17920, 35840, 71680, + 1433360, 286720, 573440, + 1146880, 2293760}; +static int lm3532_get_als_avg_index(int avg_time) +{ + if (avg_time <= als_avrg_table[0]) + return 0; + + if (avg_time > als_avrg_table[LM3532_NUM_AVG_VALS - 1]) + return LM3532_NUM_AVG_VALS - 1; + + return lm3532_get_index(&als_avrg_table[0], LM3532_NUM_AVG_VALS, + avg_time); +} + +const static int ramp_table[LM3532_NUM_RAMP_VALS] = { 8, 1024, 2048, 4096, 8192, + 16384, 32768, 65536}; +static int lm3532_get_ramp_index(int ramp_time) +{ + if (ramp_time <= ramp_table[0]) + return 0; + + if (ramp_time > ramp_table[LM3532_NUM_RAMP_VALS - 1]) + return LM3532_NUM_RAMP_VALS - 1; + + return lm3532_get_index(&ramp_table[0], LM3532_NUM_RAMP_VALS, + ramp_time); +} + +static int lm3532_led_enable(struct lm3532_led *led_data) +{ + int ctrl_en_val = BIT(led_data->control_bank); + int ret; + + ret = regmap_update_bits(led_data->priv->regmap, LM3532_REG_ENABLE, + ctrl_en_val, ctrl_en_val); + if (ret) { + dev_err(led_data->priv->dev, "Failed to set ctrl:%d\n", ret); + return ret; + } + + return regulator_enable(led_data->priv->regulator); +} + +static int lm3532_led_disable(struct lm3532_led *led_data) +{ + int ctrl_en_val = BIT(led_data->control_bank); + int ret; + + ret = regmap_update_bits(led_data->priv->regmap, LM3532_REG_ENABLE, + ctrl_en_val, ~ctrl_en_val); + if (ret) { + dev_err(led_data->priv->dev, "Failed to set ctrl:%d\n", ret); + return ret; + } + + return regulator_disable(led_data->priv->regulator); +} + +static int lm3532_brightness_set(struct led_classdev *led_cdev, + enum led_brightness brt_val) +{ + struct lm3532_led *led = + container_of(led_cdev, struct lm3532_led, led_dev); + u8 brightness_reg; + int ret; + + mutex_lock(&led->priv->lock); + + if (led->mode == LM3532_BL_MODE_ALS) { + if (brt_val > LED_OFF) + ret = lm3532_led_enable(led); + else + ret = lm3532_led_disable(led); + + goto unlock; + } + + if (brt_val == LED_OFF) { + ret = lm3532_led_disable(led); + goto unlock; + } + + ret = lm3532_led_enable(led); + if (ret) + goto unlock; + + brightness_reg = LM3532_REG_CTRL_A_BRT + led->control_bank * 2; + brt_val = brt_val / LM3532_BRT_VAL_ADJUST; + + ret = regmap_write(led->priv->regmap, brightness_reg, brt_val); + +unlock: + mutex_unlock(&led->priv->lock); + return ret; +} + +static int lm3532_init_registers(struct lm3532_led *led) +{ + struct lm3532_data *drvdata = led->priv; + unsigned int runtime_ramp_val; + unsigned int output_cfg_val = 0; + unsigned int output_cfg_shift = 0; + unsigned int output_cfg_mask = 0; + int ret, i; + + for (i = 0; i < led->num_leds; i++) { + output_cfg_shift = led->led_strings[i] * 2; + output_cfg_val |= (led->control_bank << output_cfg_shift); + output_cfg_mask |= LM3532_OUTPUT_CFG_MASK << output_cfg_shift; + } + + ret = regmap_update_bits(drvdata->regmap, LM3532_REG_OUTPUT_CFG, + output_cfg_mask, output_cfg_val); + if (ret) + return ret; + + runtime_ramp_val = drvdata->runtime_ramp_up | + (drvdata->runtime_ramp_down << LM3532_RAMP_DOWN_SHIFT); + + return regmap_write(drvdata->regmap, LM3532_REG_RT_RAMP, + runtime_ramp_val); +} + +static int lm3532_als_configure(struct lm3532_data *priv, + struct lm3532_led *led) +{ + struct lm3532_als_data *als = priv->als_data; + u32 als_vmin, als_vmax, als_vstep; + int zone_reg = LM3532_REG_ZN_0_HI; + int brightnes_config_reg; + int ret; + int i; + + als_vmin = als->als_vmin; + als_vmax = als->als_vmax; + + als_vstep = (als_vmax - als_vmin) / ((LM3532_ALS_ZB_MAX + 1) * 2); + + for (i = 0; i < LM3532_ALS_ZB_MAX; i++) { + als->zones_lo[i] = ((als_vmin + als_vstep + (i * als_vstep)) * + LED_FULL) / 1000; + als->zones_hi[i] = ((als_vmin + LM3532_ALS_OFFSET_mV + + als_vstep + (i * als_vstep)) * LED_FULL) / 1000; + + zone_reg = LM3532_REG_ZN_0_HI + i * 2; + ret = regmap_write(priv->regmap, zone_reg, als->zones_lo[i]); + if (ret) + return ret; + + zone_reg += 1; + ret = regmap_write(priv->regmap, zone_reg, als->zones_hi[i]); + if (ret) + return ret; + } + + als->config = (als->als_avrg_time | (LM3532_ENABLE_ALS) | + (als->als_input_mode << LM3532_ALS_SEL_SHIFT)); + + ret = regmap_write(priv->regmap, LM3532_ALS_CONFIG, als->config); + if (ret) + return ret; + + brightnes_config_reg = LM3532_REG_ZONE_CFG_A + led->control_bank * 2; + + return regmap_update_bits(priv->regmap, brightnes_config_reg, + LM3532_I2C_CTRL, LM3532_ALS_CTRL); +} + +static int lm3532_parse_als(struct lm3532_data *priv) +{ + struct lm3532_als_data *als; + int als_avg_time; + int als_impedance; + int ret; + + als = devm_kzalloc(priv->dev, sizeof(*als), GFP_KERNEL); + if (als == NULL) + return -ENOMEM; + + ret = device_property_read_u32(&priv->client->dev, "ti,als-vmin", + &als->als_vmin); + if (ret) + als->als_vmin = 0; + + ret = device_property_read_u32(&priv->client->dev, "ti,als-vmax", + &als->als_vmax); + if (ret) + als->als_vmax = LM3532_ALS_WINDOW_mV; + + if (als->als_vmax > LM3532_ALS_WINDOW_mV) { + ret = -EINVAL; + return ret; + } + + ret = device_property_read_u32(&priv->client->dev, "ti,als1-imp-sel", + &als_impedance); + if (ret) + als->als1_imp_sel = 0; + else + als->als1_imp_sel = lm3532_get_als_imp_index(als_impedance); + + ret = device_property_read_u32(&priv->client->dev, "ti,als2-imp-sel", + &als_impedance); + if (ret) + als->als2_imp_sel = 0; + else + als->als2_imp_sel = lm3532_get_als_imp_index(als_impedance); + + ret = device_property_read_u32(&priv->client->dev, "ti,als-avrg-time-us", + &als_avg_time); + if (ret) + als->als_avrg_time = 0; + else + als->als_avrg_time = lm3532_get_als_avg_index(als_avg_time); + + ret = device_property_read_u8(&priv->client->dev, "ti,als-input-mode", + &als->als_input_mode); + if (ret) + als->als_input_mode = 0; + + if (als->als_input_mode > LM3532_BL_MODE_ALS) { + ret = -EINVAL; + return ret; + } + + priv->als_data = als; + + return ret; +} + +static int lm3532_parse_node(struct lm3532_data *priv) +{ + struct fwnode_handle *child = NULL; + struct lm3532_led *led; + const char *name; + int control_bank; + u32 ramp_time; + 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)) + priv->enable_gpio = NULL; + + priv->regulator = devm_regulator_get(&priv->client->dev, "vin"); + if (IS_ERR(priv->regulator)) + priv->regulator = NULL; + + ret = device_property_read_u32(&priv->client->dev, "ramp-up-us", + &ramp_time); + if (ret) + dev_info(&priv->client->dev, "ramp-up-ms property missing\n"); + else + priv->runtime_ramp_up = lm3532_get_ramp_index(ramp_time); + + ret = device_property_read_u32(&priv->client->dev, "ramp-down-us", + &ramp_time); + if (ret) + dev_info(&priv->client->dev, "ramp-down-ms property missing\n"); + else + priv->runtime_ramp_down = lm3532_get_ramp_index(ramp_time); + + device_for_each_child_node(priv->dev, child) { + led = &priv->leds[i]; + + 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 > LM3532_CONTROL_C) { + dev_err(&priv->client->dev, "Control bank invalid\n"); + continue; + } + + led->control_bank = control_bank; + + ret = fwnode_property_read_u32(child, "ti,led-mode", + &led->mode); + if (ret) { + dev_err(&priv->client->dev, "ti,led-mode property missing\n"); + fwnode_handle_put(child); + goto child_out; + } + + if (led->mode == LM3532_BL_MODE_ALS) { + ret = lm3532_parse_als(priv); + if (ret) + dev_err(&priv->client->dev, "Failed to parse als\n"); + else + lm3532_als_configure(priv, led); + } + + led->num_leds = fwnode_property_read_u32_array(child, + "led-sources", + NULL, 0); + + if (led->num_leds > LM3532_MAX_LED_STRINGS) { + dev_err(&priv->client->dev, "To many LED string defined\n"); + continue; + } + + ret = fwnode_property_read_u32_array(child, "led-sources", + led->led_strings, + led->num_leds); + 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 = lm3532_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; + } + + lm3532_init_registers(led); + + i++; + } + +child_out: + return ret; +} + +static int lm3532_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct lm3532_data *drvdata; + int ret = 0; + int count; + + count = device_get_child_node_count(&client->dev); + if (!count) { + dev_err(&client->dev, "LEDs are not defined in device tree!"); + return -ENODEV; + } + + drvdata = devm_kzalloc(&client->dev, struct_size(drvdata, leds, count), + GFP_KERNEL); + if (drvdata == NULL) + return -ENOMEM; + + drvdata->client = client; + drvdata->dev = &client->dev; + + drvdata->regmap = devm_regmap_init_i2c(client, &lm3532_regmap_config); + if (IS_ERR(drvdata->regmap)) { + ret = PTR_ERR(drvdata->regmap); + dev_err(&client->dev, "Failed to allocate register map: %d\n", + ret); + return ret; + } + + mutex_init(&drvdata->lock); + i2c_set_clientdata(client, drvdata); + + ret = lm3532_parse_node(drvdata); + if (ret) { + dev_err(&client->dev, "Failed to parse node\n"); + return ret; + } + + if (drvdata->enable_gpio) + gpiod_direction_output(drvdata->enable_gpio, 1); + + return ret; +} + +static int lm3532_remove(struct i2c_client *client) +{ + struct lm3532_data *drvdata = i2c_get_clientdata(client); + + mutex_destroy(&drvdata->lock); + + if (drvdata->enable_gpio) + gpiod_direction_output(drvdata->enable_gpio, 0); + + return 0; +} + +static const struct of_device_id of_lm3532_leds_match[] = { + { .compatible = "ti,lm3532", }, + {}, +}; +MODULE_DEVICE_TABLE(of, of_lm3532_leds_match); + +static const struct i2c_device_id lm3532_id[] = { + {LM3532_NAME, 0}, + {} +}; +MODULE_DEVICE_TABLE(i2c, lm3532_id); + +static struct i2c_driver lm3532_i2c_driver = { + .probe = lm3532_probe, + .remove = lm3532_remove, + .id_table = lm3532_id, + .driver = { + .name = LM3532_NAME, + .of_match_table = of_lm3532_leds_match, + }, +}; +module_i2c_driver(lm3532_i2c_driver); + +MODULE_DESCRIPTION("Back Light driver for LM3532"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>"); |