diff options
Diffstat (limited to 'drivers/leds/leds-aw2013.c')
| -rw-r--r-- | drivers/leds/leds-aw2013.c | 441 |
1 files changed, 441 insertions, 0 deletions
diff --git a/drivers/leds/leds-aw2013.c b/drivers/leds/leds-aw2013.c new file mode 100644 index 0000000000..91f44b23cb --- /dev/null +++ b/drivers/leds/leds-aw2013.c @@ -0,0 +1,441 @@ +// SPDX-License-Identifier: GPL-2.0+ +// Driver for Awinic AW2013 3-channel LED driver + +#include <linux/i2c.h> +#include <linux/leds.h> +#include <linux/module.h> +#include <linux/regulator/consumer.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/regmap.h> + +#define AW2013_MAX_LEDS 3 + +/* Reset and ID register */ +#define AW2013_RSTR 0x00 +#define AW2013_RSTR_RESET 0x55 +#define AW2013_RSTR_CHIP_ID 0x33 + +/* Global control register */ +#define AW2013_GCR 0x01 +#define AW2013_GCR_ENABLE BIT(0) + +/* LED channel enable register */ +#define AW2013_LCTR 0x30 +#define AW2013_LCTR_LE(x) BIT((x)) + +/* LED channel control registers */ +#define AW2013_LCFG(x) (0x31 + (x)) +#define AW2013_LCFG_IMAX_MASK (BIT(0) | BIT(1)) // Should be 0-3 +#define AW2013_LCFG_MD BIT(4) +#define AW2013_LCFG_FI BIT(5) +#define AW2013_LCFG_FO BIT(6) + +/* LED channel PWM registers */ +#define AW2013_REG_PWM(x) (0x34 + (x)) + +/* LED channel timing registers */ +#define AW2013_LEDT0(x) (0x37 + (x) * 3) +#define AW2013_LEDT0_T1(x) ((x) << 4) // Should be 0-7 +#define AW2013_LEDT0_T2(x) (x) // Should be 0-5 + +#define AW2013_LEDT1(x) (0x38 + (x) * 3) +#define AW2013_LEDT1_T3(x) ((x) << 4) // Should be 0-7 +#define AW2013_LEDT1_T4(x) (x) // Should be 0-7 + +#define AW2013_LEDT2(x) (0x39 + (x) * 3) +#define AW2013_LEDT2_T0(x) ((x) << 4) // Should be 0-8 +#define AW2013_LEDT2_REPEAT(x) (x) // Should be 0-15 + +#define AW2013_REG_MAX 0x77 + +#define AW2013_TIME_STEP 130 /* ms */ + +struct aw2013; + +struct aw2013_led { + struct aw2013 *chip; + struct led_classdev cdev; + u32 num; + unsigned int imax; +}; + +struct aw2013 { + struct mutex mutex; /* held when writing to registers */ + struct regulator_bulk_data regulators[2]; + struct i2c_client *client; + struct aw2013_led leds[AW2013_MAX_LEDS]; + struct regmap *regmap; + int num_leds; + bool enabled; +}; + +static int aw2013_chip_init(struct aw2013 *chip) +{ + int i, ret; + + ret = regmap_write(chip->regmap, AW2013_GCR, AW2013_GCR_ENABLE); + if (ret) { + dev_err(&chip->client->dev, "Failed to enable the chip: %d\n", + ret); + return ret; + } + + for (i = 0; i < chip->num_leds; i++) { + ret = regmap_update_bits(chip->regmap, + AW2013_LCFG(chip->leds[i].num), + AW2013_LCFG_IMAX_MASK, + chip->leds[i].imax); + if (ret) { + dev_err(&chip->client->dev, + "Failed to set maximum current for led %d: %d\n", + chip->leds[i].num, ret); + return ret; + } + } + + return ret; +} + +static void aw2013_chip_disable(struct aw2013 *chip) +{ + int ret; + + if (!chip->enabled) + return; + + regmap_write(chip->regmap, AW2013_GCR, 0); + + ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators), + chip->regulators); + if (ret) { + dev_err(&chip->client->dev, + "Failed to disable regulators: %d\n", ret); + return; + } + + chip->enabled = false; +} + +static int aw2013_chip_enable(struct aw2013 *chip) +{ + int ret; + + if (chip->enabled) + return 0; + + ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators), + chip->regulators); + if (ret) { + dev_err(&chip->client->dev, + "Failed to enable regulators: %d\n", ret); + return ret; + } + chip->enabled = true; + + ret = aw2013_chip_init(chip); + if (ret) + aw2013_chip_disable(chip); + + return ret; +} + +static bool aw2013_chip_in_use(struct aw2013 *chip) +{ + int i; + + for (i = 0; i < chip->num_leds; i++) + if (chip->leds[i].cdev.brightness) + return true; + + return false; +} + +static int aw2013_brightness_set(struct led_classdev *cdev, + enum led_brightness brightness) +{ + struct aw2013_led *led = container_of(cdev, struct aw2013_led, cdev); + int ret, num; + + mutex_lock(&led->chip->mutex); + + if (aw2013_chip_in_use(led->chip)) { + ret = aw2013_chip_enable(led->chip); + if (ret) + goto error; + } + + num = led->num; + + ret = regmap_write(led->chip->regmap, AW2013_REG_PWM(num), brightness); + if (ret) + goto error; + + if (brightness) { + ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR, + AW2013_LCTR_LE(num), 0xFF); + } else { + ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR, + AW2013_LCTR_LE(num), 0); + if (ret) + goto error; + ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num), + AW2013_LCFG_MD, 0); + } + if (ret) + goto error; + + if (!aw2013_chip_in_use(led->chip)) + aw2013_chip_disable(led->chip); + +error: + mutex_unlock(&led->chip->mutex); + + return ret; +} + +static int aw2013_blink_set(struct led_classdev *cdev, + unsigned long *delay_on, unsigned long *delay_off) +{ + struct aw2013_led *led = container_of(cdev, struct aw2013_led, cdev); + int ret, num = led->num; + unsigned long off = 0, on = 0; + + /* If no blink specified, default to 1 Hz. */ + if (!*delay_off && !*delay_on) { + *delay_off = 500; + *delay_on = 500; + } + + if (!led->cdev.brightness) { + led->cdev.brightness = LED_FULL; + ret = aw2013_brightness_set(&led->cdev, led->cdev.brightness); + if (ret) + return ret; + } + + /* Never on - just set to off */ + if (!*delay_on) { + led->cdev.brightness = LED_OFF; + return aw2013_brightness_set(&led->cdev, LED_OFF); + } + + mutex_lock(&led->chip->mutex); + + /* Never off - brightness is already set, disable blinking */ + if (!*delay_off) { + ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num), + AW2013_LCFG_MD, 0); + goto out; + } + + /* Convert into values the HW will understand. */ + off = min(5, ilog2((*delay_off - 1) / AW2013_TIME_STEP) + 1); + on = min(7, ilog2((*delay_on - 1) / AW2013_TIME_STEP) + 1); + + *delay_off = BIT(off) * AW2013_TIME_STEP; + *delay_on = BIT(on) * AW2013_TIME_STEP; + + /* Set timings */ + ret = regmap_write(led->chip->regmap, + AW2013_LEDT0(num), AW2013_LEDT0_T2(on)); + if (ret) + goto out; + ret = regmap_write(led->chip->regmap, + AW2013_LEDT1(num), AW2013_LEDT1_T4(off)); + if (ret) + goto out; + + /* Finally, enable the LED */ + ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num), + AW2013_LCFG_MD, 0xFF); + if (ret) + goto out; + + ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR, + AW2013_LCTR_LE(num), 0xFF); + +out: + mutex_unlock(&led->chip->mutex); + + return ret; +} + +static int aw2013_probe_dt(struct aw2013 *chip) +{ + struct device_node *np = dev_of_node(&chip->client->dev), *child; + int count, ret = 0, i = 0; + struct aw2013_led *led; + + count = of_get_available_child_count(np); + if (!count || count > AW2013_MAX_LEDS) + return -EINVAL; + + regmap_write(chip->regmap, AW2013_RSTR, AW2013_RSTR_RESET); + + for_each_available_child_of_node(np, child) { + struct led_init_data init_data = {}; + u32 source; + u32 imax; + + ret = of_property_read_u32(child, "reg", &source); + if (ret != 0 || source >= AW2013_MAX_LEDS) { + dev_err(&chip->client->dev, + "Couldn't read LED address: %d\n", ret); + count--; + continue; + } + + led = &chip->leds[i]; + led->num = source; + led->chip = chip; + init_data.fwnode = of_fwnode_handle(child); + + if (!of_property_read_u32(child, "led-max-microamp", &imax)) { + led->imax = min_t(u32, imax / 5000, 3); + } else { + led->imax = 1; // 5mA + dev_info(&chip->client->dev, + "DT property led-max-microamp is missing\n"); + } + + led->cdev.brightness_set_blocking = aw2013_brightness_set; + led->cdev.blink_set = aw2013_blink_set; + + ret = devm_led_classdev_register_ext(&chip->client->dev, + &led->cdev, &init_data); + if (ret < 0) { + of_node_put(child); + return ret; + } + + i++; + } + + if (!count) + return -EINVAL; + + chip->num_leds = i; + + return 0; +} + +static const struct regmap_config aw2013_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = AW2013_REG_MAX, +}; + +static int aw2013_probe(struct i2c_client *client) +{ + struct aw2013 *chip; + int ret; + unsigned int chipid; + + chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + mutex_init(&chip->mutex); + mutex_lock(&chip->mutex); + + chip->client = client; + i2c_set_clientdata(client, chip); + + chip->regmap = devm_regmap_init_i2c(client, &aw2013_regmap_config); + if (IS_ERR(chip->regmap)) { + ret = PTR_ERR(chip->regmap); + dev_err(&client->dev, "Failed to allocate register map: %d\n", + ret); + goto error; + } + + chip->regulators[0].supply = "vcc"; + chip->regulators[1].supply = "vio"; + ret = devm_regulator_bulk_get(&client->dev, + ARRAY_SIZE(chip->regulators), + chip->regulators); + if (ret < 0) { + if (ret != -EPROBE_DEFER) + dev_err(&client->dev, + "Failed to request regulators: %d\n", ret); + goto error; + } + + ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators), + chip->regulators); + if (ret) { + dev_err(&client->dev, + "Failed to enable regulators: %d\n", ret); + goto error; + } + + ret = regmap_read(chip->regmap, AW2013_RSTR, &chipid); + if (ret) { + dev_err(&client->dev, "Failed to read chip ID: %d\n", + ret); + goto error_reg; + } + + if (chipid != AW2013_RSTR_CHIP_ID) { + dev_err(&client->dev, "Chip reported wrong ID: %x\n", + chipid); + ret = -ENODEV; + goto error_reg; + } + + ret = aw2013_probe_dt(chip); + if (ret < 0) + goto error_reg; + + ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators), + chip->regulators); + if (ret) { + dev_err(&client->dev, + "Failed to disable regulators: %d\n", ret); + goto error; + } + + mutex_unlock(&chip->mutex); + + return 0; + +error_reg: + regulator_bulk_disable(ARRAY_SIZE(chip->regulators), + chip->regulators); + +error: + mutex_destroy(&chip->mutex); + return ret; +} + +static void aw2013_remove(struct i2c_client *client) +{ + struct aw2013 *chip = i2c_get_clientdata(client); + + aw2013_chip_disable(chip); + + mutex_destroy(&chip->mutex); +} + +static const struct of_device_id aw2013_match_table[] = { + { .compatible = "awinic,aw2013", }, + { /* sentinel */ }, +}; + +MODULE_DEVICE_TABLE(of, aw2013_match_table); + +static struct i2c_driver aw2013_driver = { + .driver = { + .name = "leds-aw2013", + .of_match_table = aw2013_match_table, + }, + .probe = aw2013_probe, + .remove = aw2013_remove, +}; + +module_i2c_driver(aw2013_driver); + +MODULE_AUTHOR("Nikita Travkin <nikitos.tr@gmail.com>"); +MODULE_DESCRIPTION("AW2013 LED driver"); +MODULE_LICENSE("GPL v2"); |