1// SPDX-License-Identifier: GPL-2.0+
2// Driver for Awinic AW2013 3-channel LED driver
3
4#include <linux/i2c.h>
5#include <linux/leds.h>
6#include <linux/module.h>
7#include <linux/regulator/consumer.h>
8#include <linux/mutex.h>
9#include <linux/of.h>
10#include <linux/regmap.h>
11
12#define AW2013_MAX_LEDS 3
13
14/* Reset and ID register */
15#define AW2013_RSTR 0x00
16#define AW2013_RSTR_RESET 0x55
17#define AW2013_RSTR_CHIP_ID 0x33
18
19/* Global control register */
20#define AW2013_GCR 0x01
21#define AW2013_GCR_ENABLE BIT(0)
22
23/* LED channel enable register */
24#define AW2013_LCTR 0x30
25#define AW2013_LCTR_LE(x) BIT((x))
26
27/* LED channel control registers */
28#define AW2013_LCFG(x) (0x31 + (x))
29#define AW2013_LCFG_IMAX_MASK (BIT(0) | BIT(1)) // Should be 0-3
30#define AW2013_LCFG_MD BIT(4)
31#define AW2013_LCFG_FI BIT(5)
32#define AW2013_LCFG_FO BIT(6)
33
34/* LED channel PWM registers */
35#define AW2013_REG_PWM(x) (0x34 + (x))
36
37/* LED channel timing registers */
38#define AW2013_LEDT0(x) (0x37 + (x) * 3)
39#define AW2013_LEDT0_T1(x) ((x) << 4) // Should be 0-7
40#define AW2013_LEDT0_T2(x) (x) // Should be 0-5
41
42#define AW2013_LEDT1(x) (0x38 + (x) * 3)
43#define AW2013_LEDT1_T3(x) ((x) << 4) // Should be 0-7
44#define AW2013_LEDT1_T4(x) (x) // Should be 0-7
45
46#define AW2013_LEDT2(x) (0x39 + (x) * 3)
47#define AW2013_LEDT2_T0(x) ((x) << 4) // Should be 0-8
48#define AW2013_LEDT2_REPEAT(x) (x) // Should be 0-15
49
50#define AW2013_REG_MAX 0x77
51
52#define AW2013_TIME_STEP 130 /* ms */
53
54struct aw2013;
55
56struct aw2013_led {
57 struct aw2013 *chip;
58 struct led_classdev cdev;
59 u32 num;
60 unsigned int imax;
61};
62
63struct aw2013 {
64 struct mutex mutex; /* held when writing to registers */
65 struct regulator_bulk_data regulators[2];
66 struct i2c_client *client;
67 struct aw2013_led leds[AW2013_MAX_LEDS];
68 struct regmap *regmap;
69 int num_leds;
70 bool enabled;
71};
72
73static int aw2013_chip_init(struct aw2013 *chip)
74{
75 int i, ret;
76
77 ret = regmap_write(map: chip->regmap, AW2013_GCR, AW2013_GCR_ENABLE);
78 if (ret) {
79 dev_err(&chip->client->dev, "Failed to enable the chip: %d\n",
80 ret);
81 return ret;
82 }
83
84 for (i = 0; i < chip->num_leds; i++) {
85 ret = regmap_update_bits(map: chip->regmap,
86 AW2013_LCFG(chip->leds[i].num),
87 AW2013_LCFG_IMAX_MASK,
88 val: chip->leds[i].imax);
89 if (ret) {
90 dev_err(&chip->client->dev,
91 "Failed to set maximum current for led %d: %d\n",
92 chip->leds[i].num, ret);
93 return ret;
94 }
95 }
96
97 return ret;
98}
99
100static void aw2013_chip_disable(struct aw2013 *chip)
101{
102 int ret;
103
104 if (!chip->enabled)
105 return;
106
107 regmap_write(map: chip->regmap, AW2013_GCR, val: 0);
108
109 ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators),
110 consumers: chip->regulators);
111 if (ret) {
112 dev_err(&chip->client->dev,
113 "Failed to disable regulators: %d\n", ret);
114 return;
115 }
116
117 chip->enabled = false;
118}
119
120static int aw2013_chip_enable(struct aw2013 *chip)
121{
122 int ret;
123
124 if (chip->enabled)
125 return 0;
126
127 ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators),
128 consumers: chip->regulators);
129 if (ret) {
130 dev_err(&chip->client->dev,
131 "Failed to enable regulators: %d\n", ret);
132 return ret;
133 }
134 chip->enabled = true;
135
136 ret = aw2013_chip_init(chip);
137 if (ret)
138 aw2013_chip_disable(chip);
139
140 return ret;
141}
142
143static bool aw2013_chip_in_use(struct aw2013 *chip)
144{
145 int i;
146
147 for (i = 0; i < chip->num_leds; i++)
148 if (chip->leds[i].cdev.brightness)
149 return true;
150
151 return false;
152}
153
154static int aw2013_brightness_set(struct led_classdev *cdev,
155 enum led_brightness brightness)
156{
157 struct aw2013_led *led = container_of(cdev, struct aw2013_led, cdev);
158 int ret, num;
159
160 mutex_lock(&led->chip->mutex);
161
162 if (aw2013_chip_in_use(chip: led->chip)) {
163 ret = aw2013_chip_enable(chip: led->chip);
164 if (ret)
165 goto error;
166 }
167
168 num = led->num;
169
170 ret = regmap_write(map: led->chip->regmap, AW2013_REG_PWM(num), val: brightness);
171 if (ret)
172 goto error;
173
174 if (brightness) {
175 ret = regmap_update_bits(map: led->chip->regmap, AW2013_LCTR,
176 AW2013_LCTR_LE(num), val: 0xFF);
177 } else {
178 ret = regmap_update_bits(map: led->chip->regmap, AW2013_LCTR,
179 AW2013_LCTR_LE(num), val: 0);
180 if (ret)
181 goto error;
182 ret = regmap_update_bits(map: led->chip->regmap, AW2013_LCFG(num),
183 AW2013_LCFG_MD, val: 0);
184 }
185 if (ret)
186 goto error;
187
188 if (!aw2013_chip_in_use(chip: led->chip))
189 aw2013_chip_disable(chip: led->chip);
190
191error:
192 mutex_unlock(lock: &led->chip->mutex);
193
194 return ret;
195}
196
197static int aw2013_blink_set(struct led_classdev *cdev,
198 unsigned long *delay_on, unsigned long *delay_off)
199{
200 struct aw2013_led *led = container_of(cdev, struct aw2013_led, cdev);
201 int ret, num = led->num;
202 unsigned long off = 0, on = 0;
203
204 /* If no blink specified, default to 1 Hz. */
205 if (!*delay_off && !*delay_on) {
206 *delay_off = 500;
207 *delay_on = 500;
208 }
209
210 if (!led->cdev.brightness) {
211 led->cdev.brightness = LED_FULL;
212 ret = aw2013_brightness_set(cdev: &led->cdev, brightness: led->cdev.brightness);
213 if (ret)
214 return ret;
215 }
216
217 /* Never on - just set to off */
218 if (!*delay_on) {
219 led->cdev.brightness = LED_OFF;
220 return aw2013_brightness_set(cdev: &led->cdev, brightness: LED_OFF);
221 }
222
223 mutex_lock(&led->chip->mutex);
224
225 /* Never off - brightness is already set, disable blinking */
226 if (!*delay_off) {
227 ret = regmap_update_bits(map: led->chip->regmap, AW2013_LCFG(num),
228 AW2013_LCFG_MD, val: 0);
229 goto out;
230 }
231
232 /* Convert into values the HW will understand. */
233 off = min(5, ilog2((*delay_off - 1) / AW2013_TIME_STEP) + 1);
234 on = min(7, ilog2((*delay_on - 1) / AW2013_TIME_STEP) + 1);
235
236 *delay_off = BIT(off) * AW2013_TIME_STEP;
237 *delay_on = BIT(on) * AW2013_TIME_STEP;
238
239 /* Set timings */
240 ret = regmap_write(map: led->chip->regmap,
241 AW2013_LEDT0(num), AW2013_LEDT0_T2(on));
242 if (ret)
243 goto out;
244 ret = regmap_write(map: led->chip->regmap,
245 AW2013_LEDT1(num), AW2013_LEDT1_T4(off));
246 if (ret)
247 goto out;
248
249 /* Finally, enable the LED */
250 ret = regmap_update_bits(map: led->chip->regmap, AW2013_LCFG(num),
251 AW2013_LCFG_MD, val: 0xFF);
252 if (ret)
253 goto out;
254
255 ret = regmap_update_bits(map: led->chip->regmap, AW2013_LCTR,
256 AW2013_LCTR_LE(num), val: 0xFF);
257
258out:
259 mutex_unlock(lock: &led->chip->mutex);
260
261 return ret;
262}
263
264static int aw2013_probe_dt(struct aw2013 *chip)
265{
266 struct device_node *np = dev_of_node(dev: &chip->client->dev), *child;
267 int count, ret = 0, i = 0;
268 struct aw2013_led *led;
269
270 count = of_get_available_child_count(np);
271 if (!count || count > AW2013_MAX_LEDS)
272 return -EINVAL;
273
274 regmap_write(map: chip->regmap, AW2013_RSTR, AW2013_RSTR_RESET);
275
276 for_each_available_child_of_node(np, child) {
277 struct led_init_data init_data = {};
278 u32 source;
279 u32 imax;
280
281 ret = of_property_read_u32(np: child, propname: "reg", out_value: &source);
282 if (ret != 0 || source >= AW2013_MAX_LEDS) {
283 dev_err(&chip->client->dev,
284 "Couldn't read LED address: %d\n", ret);
285 count--;
286 continue;
287 }
288
289 led = &chip->leds[i];
290 led->num = source;
291 led->chip = chip;
292 init_data.fwnode = of_fwnode_handle(child);
293
294 if (!of_property_read_u32(np: child, propname: "led-max-microamp", out_value: &imax)) {
295 led->imax = min_t(u32, imax / 5000, 3);
296 } else {
297 led->imax = 1; // 5mA
298 dev_info(&chip->client->dev,
299 "DT property led-max-microamp is missing\n");
300 }
301
302 led->cdev.brightness_set_blocking = aw2013_brightness_set;
303 led->cdev.blink_set = aw2013_blink_set;
304
305 ret = devm_led_classdev_register_ext(parent: &chip->client->dev,
306 led_cdev: &led->cdev, init_data: &init_data);
307 if (ret < 0) {
308 of_node_put(node: child);
309 return ret;
310 }
311
312 i++;
313 }
314
315 if (!count)
316 return -EINVAL;
317
318 chip->num_leds = i;
319
320 return 0;
321}
322
323static const struct regmap_config aw2013_regmap_config = {
324 .reg_bits = 8,
325 .val_bits = 8,
326 .max_register = AW2013_REG_MAX,
327};
328
329static int aw2013_probe(struct i2c_client *client)
330{
331 struct aw2013 *chip;
332 int ret;
333 unsigned int chipid;
334
335 chip = devm_kzalloc(dev: &client->dev, size: sizeof(*chip), GFP_KERNEL);
336 if (!chip)
337 return -ENOMEM;
338
339 mutex_init(&chip->mutex);
340 mutex_lock(&chip->mutex);
341
342 chip->client = client;
343 i2c_set_clientdata(client, data: chip);
344
345 chip->regmap = devm_regmap_init_i2c(client, &aw2013_regmap_config);
346 if (IS_ERR(ptr: chip->regmap)) {
347 ret = PTR_ERR(ptr: chip->regmap);
348 dev_err(&client->dev, "Failed to allocate register map: %d\n",
349 ret);
350 goto error;
351 }
352
353 chip->regulators[0].supply = "vcc";
354 chip->regulators[1].supply = "vio";
355 ret = devm_regulator_bulk_get(dev: &client->dev,
356 ARRAY_SIZE(chip->regulators),
357 consumers: chip->regulators);
358 if (ret < 0) {
359 if (ret != -EPROBE_DEFER)
360 dev_err(&client->dev,
361 "Failed to request regulators: %d\n", ret);
362 goto error;
363 }
364
365 ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators),
366 consumers: chip->regulators);
367 if (ret) {
368 dev_err(&client->dev,
369 "Failed to enable regulators: %d\n", ret);
370 goto error;
371 }
372
373 ret = regmap_read(map: chip->regmap, AW2013_RSTR, val: &chipid);
374 if (ret) {
375 dev_err(&client->dev, "Failed to read chip ID: %d\n",
376 ret);
377 goto error_reg;
378 }
379
380 if (chipid != AW2013_RSTR_CHIP_ID) {
381 dev_err(&client->dev, "Chip reported wrong ID: %x\n",
382 chipid);
383 ret = -ENODEV;
384 goto error_reg;
385 }
386
387 ret = aw2013_probe_dt(chip);
388 if (ret < 0)
389 goto error_reg;
390
391 ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators),
392 consumers: chip->regulators);
393 if (ret) {
394 dev_err(&client->dev,
395 "Failed to disable regulators: %d\n", ret);
396 goto error;
397 }
398
399 mutex_unlock(lock: &chip->mutex);
400
401 return 0;
402
403error_reg:
404 regulator_bulk_disable(ARRAY_SIZE(chip->regulators),
405 consumers: chip->regulators);
406
407error:
408 mutex_unlock(lock: &chip->mutex);
409 mutex_destroy(lock: &chip->mutex);
410 return ret;
411}
412
413static void aw2013_remove(struct i2c_client *client)
414{
415 struct aw2013 *chip = i2c_get_clientdata(client);
416
417 aw2013_chip_disable(chip);
418
419 mutex_destroy(lock: &chip->mutex);
420}
421
422static const struct of_device_id aw2013_match_table[] = {
423 { .compatible = "awinic,aw2013", },
424 { /* sentinel */ },
425};
426
427MODULE_DEVICE_TABLE(of, aw2013_match_table);
428
429static struct i2c_driver aw2013_driver = {
430 .driver = {
431 .name = "leds-aw2013",
432 .of_match_table = aw2013_match_table,
433 },
434 .probe = aw2013_probe,
435 .remove = aw2013_remove,
436};
437
438module_i2c_driver(aw2013_driver);
439
440MODULE_AUTHOR("Nikita Travkin <nikitos.tr@gmail.com>");
441MODULE_DESCRIPTION("AW2013 LED driver");
442MODULE_LICENSE("GPL v2");
443

source code of linux/drivers/leds/leds-aw2013.c