1 // SPDX-License-Identifier: GPL-2.0+
3 // Driver for Panasonic AN30259A 3-channel LED driver
5 // Copyright (c) 2018 Simon Shields <simon@lineageos.org>
8 // https://www.alliedelec.com/m/d/a9d2b3ee87c2d1a535a41dd747b1c247.pdf
10 #include <linux/i2c.h>
11 #include <linux/leds.h>
12 #include <linux/module.h>
13 #include <linux/mutex.h>
15 #include <linux/regmap.h>
16 #include <uapi/linux/uleds.h>
18 #define AN30259A_MAX_LEDS 3
20 #define AN30259A_REG_SRESET 0x00
21 #define AN30259A_LED_SRESET BIT(0)
23 /* LED power registers */
24 #define AN30259A_REG_LED_ON 0x01
25 #define AN30259A_LED_EN(x) BIT((x) - 1)
26 #define AN30259A_LED_SLOPE(x) BIT(((x) - 1) + 4)
28 #define AN30259A_REG_LEDCC(x) (0x03 + ((x) - 1))
30 /* slope control registers */
31 #define AN30259A_REG_SLOPE(x) (0x06 + ((x) - 1))
32 #define AN30259A_LED_SLOPETIME1(x) (x)
33 #define AN30259A_LED_SLOPETIME2(x) ((x) << 4)
35 #define AN30259A_REG_LEDCNT1(x) (0x09 + (4 * ((x) - 1)))
36 #define AN30259A_LED_DUTYMAX(x) ((x) << 4)
37 #define AN30259A_LED_DUTYMID(x) (x)
39 #define AN30259A_REG_LEDCNT2(x) (0x0A + (4 * ((x) - 1)))
40 #define AN30259A_LED_DELAY(x) ((x) << 4)
41 #define AN30259A_LED_DUTYMIN(x) (x)
43 /* detention time control (length of each slope step) */
44 #define AN30259A_REG_LEDCNT3(x) (0x0B + (4 * ((x) - 1)))
45 #define AN30259A_LED_DT1(x) (x)
46 #define AN30259A_LED_DT2(x) ((x) << 4)
48 #define AN30259A_REG_LEDCNT4(x) (0x0C + (4 * ((x) - 1)))
49 #define AN30259A_LED_DT3(x) (x)
50 #define AN30259A_LED_DT4(x) ((x) << 4)
52 #define AN30259A_REG_MAX 0x14
54 #define AN30259A_BLINK_MAX_TIME 7500 /* ms */
55 #define AN30259A_SLOPE_RESOLUTION 500 /* ms */
64 struct an30259a *chip;
65 struct led_classdev cdev;
69 char label[LED_MAX_NAME_SIZE];
73 struct mutex mutex; /* held when writing to registers */
74 struct i2c_client *client;
75 struct an30259a_led leds[AN30259A_MAX_LEDS];
76 struct regmap *regmap;
80 static int an30259a_brightness_set(struct led_classdev *cdev,
81 enum led_brightness brightness)
83 struct an30259a_led *led;
87 led = container_of(cdev, struct an30259a_led, cdev);
88 mutex_lock(&led->chip->mutex);
90 ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on);
96 led_on &= ~AN30259A_LED_EN(led->num);
97 led_on &= ~AN30259A_LED_SLOPE(led->num);
101 led_on |= AN30259A_LED_EN(led->num);
103 led_on |= AN30259A_LED_SLOPE(led->num);
104 ret = regmap_write(led->chip->regmap,
105 AN30259A_REG_LEDCNT1(led->num),
106 AN30259A_LED_DUTYMAX(0xf) |
107 AN30259A_LED_DUTYMID(0xf));
113 ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on);
117 ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCC(led->num),
121 mutex_unlock(&led->chip->mutex);
126 static int an30259a_blink_set(struct led_classdev *cdev,
127 unsigned long *delay_off, unsigned long *delay_on)
129 struct an30259a_led *led;
132 unsigned long off = *delay_off, on = *delay_on;
134 led = container_of(cdev, struct an30259a_led, cdev);
136 mutex_lock(&led->chip->mutex);
139 /* slope time can only be a multiple of 500ms. */
140 if (off % AN30259A_SLOPE_RESOLUTION || on % AN30259A_SLOPE_RESOLUTION) {
145 /* up to a maximum of 7500ms. */
146 if (off > AN30259A_BLINK_MAX_TIME || on > AN30259A_BLINK_MAX_TIME) {
151 /* if no blink specified, default to 1 Hz. */
153 *delay_off = off = 500;
154 *delay_on = on = 500;
157 /* convert into values the HW will understand. */
158 off /= AN30259A_SLOPE_RESOLUTION;
159 on /= AN30259A_SLOPE_RESOLUTION;
161 /* duty min should be zero (=off), delay should be zero. */
162 ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT2(num),
163 AN30259A_LED_DELAY(0) | AN30259A_LED_DUTYMIN(0));
167 /* reset detention time (no "breathing" effect). */
168 ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT3(num),
169 AN30259A_LED_DT1(0) | AN30259A_LED_DT2(0));
172 ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT4(num),
173 AN30259A_LED_DT3(0) | AN30259A_LED_DT4(0));
177 /* slope time controls on/off cycle length. */
178 ret = regmap_write(led->chip->regmap, AN30259A_REG_SLOPE(num),
179 AN30259A_LED_SLOPETIME1(off) |
180 AN30259A_LED_SLOPETIME2(on));
184 /* Finally, enable slope mode. */
185 ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on);
189 led_on |= AN30259A_LED_SLOPE(num) | AN30259A_LED_EN(led->num);
191 ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on);
196 mutex_unlock(&led->chip->mutex);
201 static int an30259a_dt_init(struct i2c_client *client,
202 struct an30259a *chip)
204 struct device_node *np = client->dev.of_node, *child;
208 struct an30259a_led *led;
210 count = of_get_child_count(np);
211 if (!count || count > AN30259A_MAX_LEDS)
214 for_each_available_child_of_node(np, child) {
217 ret = of_property_read_u32(child, "reg", &source);
218 if (ret != 0 || !source || source > AN30259A_MAX_LEDS) {
219 dev_err(&client->dev, "Couldn't read LED address: %d\n",
225 led = &chip->leds[i];
230 if (of_property_read_string(child, "label", &str))
231 snprintf(led->label, sizeof(led->label), "an30259a::");
233 snprintf(led->label, sizeof(led->label), "an30259a:%s",
236 led->cdev.name = led->label;
238 if (!of_property_read_string(child, "default-state", &str)) {
239 if (!strcmp(str, "on"))
240 led->default_state = STATE_ON;
241 else if (!strcmp(str, "keep"))
242 led->default_state = STATE_KEEP;
244 led->default_state = STATE_OFF;
247 of_property_read_string(child, "linux,default-trigger",
248 &led->cdev.default_trigger);
261 static const struct regmap_config an30259a_regmap_config = {
264 .max_register = AN30259A_REG_MAX,
267 static void an30259a_init_default_state(struct an30259a_led *led)
269 struct an30259a *chip = led->chip;
272 switch (led->default_state) {
274 led->cdev.brightness = LED_FULL;
277 err = regmap_read(chip->regmap, AN30259A_REG_LED_ON, &led_on);
281 if (!(led_on & AN30259A_LED_EN(led->num))) {
282 led->cdev.brightness = LED_OFF;
285 regmap_read(chip->regmap, AN30259A_REG_LEDCC(led->num),
286 &led->cdev.brightness);
289 led->cdev.brightness = LED_OFF;
292 an30259a_brightness_set(&led->cdev, led->cdev.brightness);
295 static int an30259a_probe(struct i2c_client *client)
297 struct an30259a *chip;
300 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
304 err = an30259a_dt_init(client, chip);
308 mutex_init(&chip->mutex);
309 chip->client = client;
310 i2c_set_clientdata(client, chip);
312 chip->regmap = devm_regmap_init_i2c(client, &an30259a_regmap_config);
314 for (i = 0; i < chip->num_leds; i++) {
315 an30259a_init_default_state(&chip->leds[i]);
316 chip->leds[i].cdev.brightness_set_blocking =
317 an30259a_brightness_set;
318 chip->leds[i].cdev.blink_set = an30259a_blink_set;
320 err = devm_led_classdev_register(&client->dev,
321 &chip->leds[i].cdev);
328 mutex_destroy(&chip->mutex);
332 static int an30259a_remove(struct i2c_client *client)
334 struct an30259a *chip = i2c_get_clientdata(client);
336 mutex_destroy(&chip->mutex);
341 static const struct of_device_id an30259a_match_table[] = {
342 { .compatible = "panasonic,an30259a", },
346 MODULE_DEVICE_TABLE(of, an30259a_match_table);
348 static const struct i2c_device_id an30259a_id[] = {
352 MODULE_DEVICE_TABLE(i2c, an30259a_id);
354 static struct i2c_driver an30259a_driver = {
356 .name = "leds-an32059a",
357 .of_match_table = of_match_ptr(an30259a_match_table),
359 .probe_new = an30259a_probe,
360 .remove = an30259a_remove,
361 .id_table = an30259a_id,
364 module_i2c_driver(an30259a_driver);
366 MODULE_AUTHOR("Simon Shields <simon@lineageos.org>");
367 MODULE_DESCRIPTION("AN32059A LED driver");
368 MODULE_LICENSE("GPL v2");