// SPDX-License-Identifier: GPL-2.0+ // // Driver for Panasonic AN30259A 3-channel LED driver // // Copyright (c) 2018 Simon Shields <simon@lineageos.org> // // Datasheet: // https://www.alliedelec.com/m/d/a9d2b3ee87c2d1a535a41dd747b1c247.pdf #include <linux/i2c.h> #include <linux/leds.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/of.h> #include <linux/regmap.h> #define AN30259A_MAX_LEDS 3 #define AN30259A_REG_SRESET 0x00 #define AN30259A_LED_SRESET BIT(0) /* LED power registers */ #define AN30259A_REG_LED_ON 0x01 #define AN30259A_LED_EN(x) BIT((x) - 1) #define AN30259A_LED_SLOPE(x) BIT(((x) - 1) + 4) #define AN30259A_REG_LEDCC(x) (0x03 + ((x) - 1)) /* slope control registers */ #define AN30259A_REG_SLOPE(x) (0x06 + ((x) - 1)) #define AN30259A_LED_SLOPETIME1(x) (x) #define AN30259A_LED_SLOPETIME2(x) ((x) << 4) #define AN30259A_REG_LEDCNT1(x) (0x09 + (4 * ((x) - 1))) #define AN30259A_LED_DUTYMAX(x) ((x) << 4) #define AN30259A_LED_DUTYMID(x) (x) #define AN30259A_REG_LEDCNT2(x) (0x0A + (4 * ((x) - 1))) #define AN30259A_LED_DELAY(x) ((x) << 4) #define AN30259A_LED_DUTYMIN(x) (x) /* detention time control (length of each slope step) */ #define AN30259A_REG_LEDCNT3(x) (0x0B + (4 * ((x) - 1))) #define AN30259A_LED_DT1(x) (x) #define AN30259A_LED_DT2(x) ((x) << 4) #define AN30259A_REG_LEDCNT4(x) (0x0C + (4 * ((x) - 1))) #define AN30259A_LED_DT3(x) (x) #define AN30259A_LED_DT4(x) ((x) << 4) #define AN30259A_REG_MAX 0x14 #define AN30259A_BLINK_MAX_TIME 7500 /* ms */ #define AN30259A_SLOPE_RESOLUTION 500 /* ms */ #define AN30259A_NAME "an30259a" #define STATE_OFF 0 #define STATE_KEEP 1 #define STATE_ON 2 struct an30259a; struct an30259a_led { struct an30259a *chip; struct fwnode_handle *fwnode; struct led_classdev cdev; u32 num; u32 default_state; bool sloping; }; struct an30259a { struct mutex mutex; /* held when writing to registers */ struct i2c_client *client; struct an30259a_led leds[AN30259A_MAX_LEDS]; struct regmap *regmap; int num_leds; }; static int an30259a_brightness_set(struct led_classdev *cdev, enum led_brightness brightness) { struct an30259a_led *led; int ret; unsigned int led_on; led = container_of(cdev, struct an30259a_led, cdev); mutex_lock(&led->chip->mutex); ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on); if (ret) goto error; switch (brightness) { case LED_OFF: led_on &= ~AN30259A_LED_EN(led->num); led_on &= ~AN30259A_LED_SLOPE(led->num); led->sloping = false; break; default: led_on |= AN30259A_LED_EN(led->num); if (led->sloping) led_on |= AN30259A_LED_SLOPE(led->num); ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT1(led->num), AN30259A_LED_DUTYMAX(0xf) | AN30259A_LED_DUTYMID(0xf)); if (ret) goto error; break; } ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on); if (ret) goto error; ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCC(led->num), brightness); error: mutex_unlock(&led->chip->mutex); return ret; } static int an30259a_blink_set(struct led_classdev *cdev, unsigned long *delay_off, unsigned long *delay_on) { struct an30259a_led *led; int ret, num; unsigned int led_on; unsigned long off = *delay_off, on = *delay_on; led = container_of(cdev, struct an30259a_led, cdev); mutex_lock(&led->chip->mutex); num = led->num; /* slope time can only be a multiple of 500ms. */ if (off % AN30259A_SLOPE_RESOLUTION || on % AN30259A_SLOPE_RESOLUTION) { ret = -EINVAL; goto error; } /* up to a maximum of 7500ms. */ if (off > AN30259A_BLINK_MAX_TIME || on > AN30259A_BLINK_MAX_TIME) { ret = -EINVAL; goto error; } /* if no blink specified, default to 1 Hz. */ if (!off && !on) { *delay_off = off = 500; *delay_on = on = 500; } /* convert into values the HW will understand. */ off /= AN30259A_SLOPE_RESOLUTION; on /= AN30259A_SLOPE_RESOLUTION; /* duty min should be zero (=off), delay should be zero. */ ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT2(num), AN30259A_LED_DELAY(0) | AN30259A_LED_DUTYMIN(0)); if (ret) goto error; /* reset detention time (no "breathing" effect). */ ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT3(num), AN30259A_LED_DT1(0) | AN30259A_LED_DT2(0)); if (ret) goto error; ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT4(num), AN30259A_LED_DT3(0) | AN30259A_LED_DT4(0)); if (ret) goto error; /* slope time controls on/off cycle length. */ ret = regmap_write(led->chip->regmap, AN30259A_REG_SLOPE(num), AN30259A_LED_SLOPETIME1(off) | AN30259A_LED_SLOPETIME2(on)); if (ret) goto error; /* Finally, enable slope mode. */ ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on); if (ret) goto error; led_on |= AN30259A_LED_SLOPE(num) | AN30259A_LED_EN(led->num); ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on); if (!ret) led->sloping = true; error: mutex_unlock(&led->chip->mutex); return ret; } static int an30259a_dt_init(struct i2c_client *client, struct an30259a *chip) { struct device_node *np = dev_of_node(&client->dev), *child; int count, ret; int i = 0; const char *str; struct an30259a_led *led; count = of_get_available_child_count(np); if (!count || count > AN30259A_MAX_LEDS) return -EINVAL; for_each_available_child_of_node(np, child) { u32 source; ret = of_property_read_u32(child, "reg", &source); if (ret != 0 || !source || source > AN30259A_MAX_LEDS) { dev_err(&client->dev, "Couldn't read LED address: %d\n", ret); count--; continue; } led = &chip->leds[i]; led->num = source; led->chip = chip; led->fwnode = of_fwnode_handle(child); if (!of_property_read_string(child, "default-state", &str)) { if (!strcmp(str, "on")) led->default_state = STATE_ON; else if (!strcmp(str, "keep")) led->default_state = STATE_KEEP; else led->default_state = STATE_OFF; } i++; } if (!count) return -EINVAL; chip->num_leds = i; return 0; } static const struct regmap_config an30259a_regmap_config = { .reg_bits = 8, .val_bits = 8, .max_register = AN30259A_REG_MAX, }; static void an30259a_init_default_state(struct an30259a_led *led) { struct an30259a *chip = led->chip; int led_on, err; switch (led->default_state) { case STATE_ON: led->cdev.brightness = LED_FULL; break; case STATE_KEEP: err = regmap_read(chip->regmap, AN30259A_REG_LED_ON, &led_on); if (err) break; if (!(led_on & AN30259A_LED_EN(led->num))) { led->cdev.brightness = LED_OFF; break; } regmap_read(chip->regmap, AN30259A_REG_LEDCC(led->num), &led->cdev.brightness); break; default: led->cdev.brightness = LED_OFF; } an30259a_brightness_set(&led->cdev, led->cdev.brightness); } static int an30259a_probe(struct i2c_client *client) { struct an30259a *chip; int i, err; chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); if (!chip) return -ENOMEM; err = an30259a_dt_init(client, chip); if (err < 0) return err; mutex_init(&chip->mutex); chip->client = client; i2c_set_clientdata(client, chip); chip->regmap = devm_regmap_init_i2c(client, &an30259a_regmap_config); if (IS_ERR(chip->regmap)) { err = PTR_ERR(chip->regmap); dev_err(&client->dev, "Failed to allocate register map: %d\n", err); goto exit; } for (i = 0; i < chip->num_leds; i++) { struct led_init_data init_data = {}; an30259a_init_default_state(&chip->leds[i]); chip->leds[i].cdev.brightness_set_blocking = an30259a_brightness_set; chip->leds[i].cdev.blink_set = an30259a_blink_set; init_data.fwnode = chip->leds[i].fwnode; init_data.devicename = AN30259A_NAME; init_data.default_label = ":"; err = devm_led_classdev_register_ext(&client->dev, &chip->leds[i].cdev, &init_data); if (err < 0) goto exit; } return 0; exit: mutex_destroy(&chip->mutex); return err; } static int an30259a_remove(struct i2c_client *client) { struct an30259a *chip = i2c_get_clientdata(client); mutex_destroy(&chip->mutex); return 0; } static const struct of_device_id an30259a_match_table[] = { { .compatible = "panasonic,an30259a", }, { /* sentinel */ }, }; MODULE_DEVICE_TABLE(of, an30259a_match_table); static const struct i2c_device_id an30259a_id[] = { { "an30259a", 0 }, { /* sentinel */ }, }; MODULE_DEVICE_TABLE(i2c, an30259a_id); static struct i2c_driver an30259a_driver = { .driver = { .name = "leds-an30259a", .of_match_table = of_match_ptr(an30259a_match_table), }, .probe_new = an30259a_probe, .remove = an30259a_remove, .id_table = an30259a_id, }; module_i2c_driver(an30259a_driver); MODULE_AUTHOR("Simon Shields <simon@lineageos.org>"); MODULE_DESCRIPTION("AN30259A LED driver"); MODULE_LICENSE("GPL v2");