1
2
3
4
5#include <linux/gpio/consumer.h>
6#include <linux/i2c.h>
7#include <linux/init.h>
8#include <linux/leds.h>
9#include <linux/log2.h>
10#include <linux/module.h>
11#include <linux/mutex.h>
12#include <linux/of.h>
13#include <linux/of_gpio.h>
14#include <linux/regmap.h>
15#include <linux/regulator/consumer.h>
16#include <linux/slab.h>
17
18#define LM36922_MODEL 0
19#define LM36923_MODEL 1
20
21#define LM3692X_REV 0x0
22#define LM3692X_RESET 0x1
23#define LM3692X_EN 0x10
24#define LM3692X_BRT_CTRL 0x11
25#define LM3692X_PWM_CTRL 0x12
26#define LM3692X_BOOST_CTRL 0x13
27#define LM3692X_AUTO_FREQ_HI 0x15
28#define LM3692X_AUTO_FREQ_LO 0x16
29#define LM3692X_BL_ADJ_THRESH 0x17
30#define LM3692X_BRT_LSB 0x18
31#define LM3692X_BRT_MSB 0x19
32#define LM3692X_FAULT_CTRL 0x1e
33#define LM3692X_FAULT_FLAGS 0x1f
34
35#define LM3692X_SW_RESET BIT(0)
36#define LM3692X_DEVICE_EN BIT(0)
37#define LM3692X_LED1_EN BIT(1)
38#define LM3692X_LED2_EN BIT(2)
39#define LM36923_LED3_EN BIT(3)
40#define LM3692X_ENABLE_MASK (LM3692X_DEVICE_EN | LM3692X_LED1_EN | \
41 LM3692X_LED2_EN | LM36923_LED3_EN)
42
43
44#define LM3692X_BL_ADJ_POL BIT(0)
45#define LM3692X_RAMP_RATE_125us 0x00
46#define LM3692X_RAMP_RATE_250us BIT(1)
47#define LM3692X_RAMP_RATE_500us BIT(2)
48#define LM3692X_RAMP_RATE_1ms (BIT(1) | BIT(2))
49#define LM3692X_RAMP_RATE_2ms BIT(3)
50#define LM3692X_RAMP_RATE_4ms (BIT(3) | BIT(1))
51#define LM3692X_RAMP_RATE_8ms (BIT(2) | BIT(3))
52#define LM3692X_RAMP_RATE_16ms (BIT(1) | BIT(2) | BIT(3))
53#define LM3692X_RAMP_EN BIT(4)
54#define LM3692X_BRHT_MODE_REG 0x00
55#define LM3692X_BRHT_MODE_PWM BIT(5)
56#define LM3692X_BRHT_MODE_MULTI_RAMP BIT(6)
57#define LM3692X_BRHT_MODE_RAMP_MULTI (BIT(5) | BIT(6))
58#define LM3692X_MAP_MODE_EXP BIT(7)
59
60
61#define LM3692X_PWM_FILTER_100 BIT(0)
62#define LM3692X_PWM_FILTER_150 BIT(1)
63#define LM3692X_PWM_FILTER_200 (BIT(0) | BIT(1))
64#define LM3692X_PWM_HYSTER_1LSB BIT(2)
65#define LM3692X_PWM_HYSTER_2LSB BIT(3)
66#define LM3692X_PWM_HYSTER_3LSB (BIT(3) | BIT(2))
67#define LM3692X_PWM_HYSTER_4LSB BIT(4)
68#define LM3692X_PWM_HYSTER_5LSB (BIT(4) | BIT(2))
69#define LM3692X_PWM_HYSTER_6LSB (BIT(4) | BIT(3))
70#define LM3692X_PWM_POLARITY BIT(5)
71#define LM3692X_PWM_SAMP_4MHZ BIT(6)
72#define LM3692X_PWM_SAMP_24MHZ BIT(7)
73
74
75#define LM3692X_OCP_PROT_1A BIT(0)
76#define LM3692X_OCP_PROT_1_25A BIT(1)
77#define LM3692X_OCP_PROT_1_5A (BIT(0) | BIT(1))
78#define LM3692X_OVP_21V BIT(2)
79#define LM3692X_OVP_25V BIT(3)
80#define LM3692X_OVP_29V (BIT(2) | BIT(3))
81#define LM3692X_MIN_IND_22UH BIT(4)
82#define LM3692X_BOOST_SW_1MHZ BIT(5)
83#define LM3692X_BOOST_SW_NO_SHIFT BIT(6)
84
85
86#define LM3692X_FAULT_CTRL_OVP BIT(0)
87#define LM3692X_FAULT_CTRL_OCP BIT(1)
88#define LM3692X_FAULT_CTRL_TSD BIT(2)
89#define LM3692X_FAULT_CTRL_OPEN BIT(3)
90
91
92#define LM3692X_FAULT_FLAG_OVP BIT(0)
93#define LM3692X_FAULT_FLAG_OCP BIT(1)
94#define LM3692X_FAULT_FLAG_TSD BIT(2)
95#define LM3692X_FAULT_FLAG_SHRT BIT(3)
96#define LM3692X_FAULT_FLAG_OPEN BIT(4)
97
98
99
100
101
102
103
104
105
106
107
108
109struct lm3692x_led {
110 struct mutex lock;
111 struct i2c_client *client;
112 struct led_classdev led_dev;
113 struct regmap *regmap;
114 struct gpio_desc *enable_gpio;
115 struct regulator *regulator;
116 int led_enable;
117 int model_id;
118
119 u8 boost_ctrl, brightness_ctrl;
120 bool enabled;
121};
122
123static const struct reg_default lm3692x_reg_defs[] = {
124 {LM3692X_EN, 0xf},
125 {LM3692X_BRT_CTRL, 0x61},
126 {LM3692X_PWM_CTRL, 0x73},
127 {LM3692X_BOOST_CTRL, 0x6f},
128 {LM3692X_AUTO_FREQ_HI, 0x0},
129 {LM3692X_AUTO_FREQ_LO, 0x0},
130 {LM3692X_BL_ADJ_THRESH, 0x0},
131 {LM3692X_BRT_LSB, 0x7},
132 {LM3692X_BRT_MSB, 0xff},
133 {LM3692X_FAULT_CTRL, 0x7},
134};
135
136static const struct regmap_config lm3692x_regmap_config = {
137 .reg_bits = 8,
138 .val_bits = 8,
139
140 .max_register = LM3692X_FAULT_FLAGS,
141 .reg_defaults = lm3692x_reg_defs,
142 .num_reg_defaults = ARRAY_SIZE(lm3692x_reg_defs),
143 .cache_type = REGCACHE_RBTREE,
144};
145
146static int lm3692x_fault_check(struct lm3692x_led *led)
147{
148 int ret;
149 unsigned int read_buf;
150
151 ret = regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);
152 if (ret)
153 return ret;
154
155 if (read_buf)
156 dev_err(&led->client->dev, "Detected a fault 0x%X\n", read_buf);
157
158
159
160
161 regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);
162 if (read_buf)
163 dev_err(&led->client->dev, "Second read of fault flags 0x%X\n",
164 read_buf);
165
166 return read_buf;
167}
168
169static int lm3692x_leds_enable(struct lm3692x_led *led)
170{
171 int enable_state;
172 int ret, reg_ret;
173
174 if (led->enabled)
175 return 0;
176
177 if (led->regulator) {
178 ret = regulator_enable(led->regulator);
179 if (ret) {
180 dev_err(&led->client->dev,
181 "Failed to enable regulator: %d\n", ret);
182 return ret;
183 }
184 }
185
186 if (led->enable_gpio)
187 gpiod_direction_output(led->enable_gpio, 1);
188
189 ret = lm3692x_fault_check(led);
190 if (ret) {
191 dev_err(&led->client->dev, "Cannot read/clear faults: %d\n",
192 ret);
193 goto out;
194 }
195
196 ret = regmap_write(led->regmap, LM3692X_BRT_CTRL, 0x00);
197 if (ret)
198 goto out;
199
200
201
202
203
204
205
206 ret = regmap_write(led->regmap, LM3692X_EN, LM3692X_DEVICE_EN);
207 if (ret)
208 goto out;
209
210
211
212
213 ret = regmap_write(led->regmap, LM3692X_BRT_MSB, 0);
214 if (ret)
215 goto out;
216
217 ret = regmap_write(led->regmap, LM3692X_BRT_LSB, 0);
218 if (ret)
219 goto out;
220
221 ret = regmap_write(led->regmap, LM3692X_PWM_CTRL,
222 LM3692X_PWM_FILTER_100 | LM3692X_PWM_SAMP_24MHZ);
223 if (ret)
224 goto out;
225
226 ret = regmap_write(led->regmap, LM3692X_BOOST_CTRL, led->boost_ctrl);
227 if (ret)
228 goto out;
229
230 ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_HI, 0x00);
231 if (ret)
232 goto out;
233
234 ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_LO, 0x00);
235 if (ret)
236 goto out;
237
238 ret = regmap_write(led->regmap, LM3692X_BL_ADJ_THRESH, 0x00);
239 if (ret)
240 goto out;
241
242 ret = regmap_write(led->regmap, LM3692X_BRT_CTRL,
243 LM3692X_BL_ADJ_POL | LM3692X_RAMP_EN);
244 if (ret)
245 goto out;
246
247 switch (led->led_enable) {
248 case 0:
249 default:
250 if (led->model_id == LM36923_MODEL)
251 enable_state = LM3692X_LED1_EN | LM3692X_LED2_EN |
252 LM36923_LED3_EN;
253 else
254 enable_state = LM3692X_LED1_EN | LM3692X_LED2_EN;
255
256 break;
257 case 1:
258 enable_state = LM3692X_LED1_EN;
259 break;
260 case 2:
261 enable_state = LM3692X_LED2_EN;
262 break;
263
264 case 3:
265 if (led->model_id == LM36923_MODEL) {
266 enable_state = LM36923_LED3_EN;
267 break;
268 }
269
270 ret = -EINVAL;
271 dev_err(&led->client->dev,
272 "LED3 sync not available on this device\n");
273 goto out;
274 }
275
276 ret = regmap_update_bits(led->regmap, LM3692X_EN, LM3692X_ENABLE_MASK,
277 enable_state | LM3692X_DEVICE_EN);
278
279 led->enabled = true;
280 return ret;
281out:
282 dev_err(&led->client->dev, "Fail writing initialization values\n");
283
284 if (led->enable_gpio)
285 gpiod_direction_output(led->enable_gpio, 0);
286
287 if (led->regulator) {
288 reg_ret = regulator_disable(led->regulator);
289 if (reg_ret)
290 dev_err(&led->client->dev,
291 "Failed to disable regulator: %d\n", reg_ret);
292 }
293
294 return ret;
295}
296
297static int lm3692x_leds_disable(struct lm3692x_led *led)
298{
299 int ret;
300
301 if (!led->enabled)
302 return 0;
303
304 ret = regmap_update_bits(led->regmap, LM3692X_EN, LM3692X_DEVICE_EN, 0);
305 if (ret) {
306 dev_err(&led->client->dev, "Failed to disable regulator: %d\n",
307 ret);
308 return ret;
309 }
310
311 if (led->enable_gpio)
312 gpiod_direction_output(led->enable_gpio, 0);
313
314 if (led->regulator) {
315 ret = regulator_disable(led->regulator);
316 if (ret)
317 dev_err(&led->client->dev,
318 "Failed to disable regulator: %d\n", ret);
319 }
320
321 led->enabled = false;
322 return ret;
323}
324
325static int lm3692x_brightness_set(struct led_classdev *led_cdev,
326 enum led_brightness brt_val)
327{
328 struct lm3692x_led *led =
329 container_of(led_cdev, struct lm3692x_led, led_dev);
330 int ret;
331 int led_brightness_lsb = (brt_val >> 5);
332
333 mutex_lock(&led->lock);
334
335 if (brt_val == 0) {
336 ret = lm3692x_leds_disable(led);
337 goto out;
338 } else {
339 lm3692x_leds_enable(led);
340 }
341
342 ret = lm3692x_fault_check(led);
343 if (ret) {
344 dev_err(&led->client->dev, "Cannot read/clear faults: %d\n",
345 ret);
346 goto out;
347 }
348
349 ret = regmap_write(led->regmap, LM3692X_BRT_MSB, brt_val);
350 if (ret) {
351 dev_err(&led->client->dev, "Cannot write MSB: %d\n", ret);
352 goto out;
353 }
354
355 ret = regmap_write(led->regmap, LM3692X_BRT_LSB, led_brightness_lsb);
356 if (ret) {
357 dev_err(&led->client->dev, "Cannot write LSB: %d\n", ret);
358 goto out;
359 }
360out:
361 mutex_unlock(&led->lock);
362 return ret;
363}
364
365static enum led_brightness lm3692x_max_brightness(struct lm3692x_led *led,
366 u32 max_cur)
367{
368 u32 max_code;
369
370
371 max_code = ((max_cur * 1000) - 37806) / 12195;
372 if (max_code > 0x7FF)
373 max_code = 0x7FF;
374
375 return max_code >> 3;
376}
377
378static int lm3692x_probe_dt(struct lm3692x_led *led)
379{
380 struct fwnode_handle *child = NULL;
381 struct led_init_data init_data = {};
382 u32 ovp, max_cur;
383 int ret;
384
385 led->enable_gpio = devm_gpiod_get_optional(&led->client->dev,
386 "enable", GPIOD_OUT_LOW);
387 if (IS_ERR(led->enable_gpio)) {
388 ret = PTR_ERR(led->enable_gpio);
389 dev_err(&led->client->dev, "Failed to get enable gpio: %d\n",
390 ret);
391 return ret;
392 }
393
394 led->regulator = devm_regulator_get_optional(&led->client->dev, "vled");
395 if (IS_ERR(led->regulator)) {
396 ret = PTR_ERR(led->regulator);
397 if (ret != -ENODEV)
398 return dev_err_probe(&led->client->dev, ret,
399 "Failed to get vled regulator\n");
400
401 led->regulator = NULL;
402 }
403
404 led->boost_ctrl = LM3692X_BOOST_SW_1MHZ |
405 LM3692X_BOOST_SW_NO_SHIFT |
406 LM3692X_OCP_PROT_1_5A;
407 ret = device_property_read_u32(&led->client->dev,
408 "ti,ovp-microvolt", &ovp);
409 if (ret) {
410 led->boost_ctrl |= LM3692X_OVP_29V;
411 } else {
412 switch (ovp) {
413 case 17000000:
414 break;
415 case 21000000:
416 led->boost_ctrl |= LM3692X_OVP_21V;
417 break;
418 case 25000000:
419 led->boost_ctrl |= LM3692X_OVP_25V;
420 break;
421 case 29000000:
422 led->boost_ctrl |= LM3692X_OVP_29V;
423 break;
424 default:
425 dev_err(&led->client->dev, "Invalid OVP %d\n", ovp);
426 return -EINVAL;
427 }
428 }
429
430 child = device_get_next_child_node(&led->client->dev, child);
431 if (!child) {
432 dev_err(&led->client->dev, "No LED Child node\n");
433 return -ENODEV;
434 }
435
436 ret = fwnode_property_read_u32(child, "reg", &led->led_enable);
437 if (ret) {
438 dev_err(&led->client->dev, "reg DT property missing\n");
439 return ret;
440 }
441
442 ret = fwnode_property_read_u32(child, "led-max-microamp", &max_cur);
443 led->led_dev.max_brightness = ret ? LED_FULL :
444 lm3692x_max_brightness(led, max_cur);
445
446 init_data.fwnode = child;
447 init_data.devicename = led->client->name;
448 init_data.default_label = ":";
449
450 ret = devm_led_classdev_register_ext(&led->client->dev, &led->led_dev,
451 &init_data);
452 if (ret) {
453 dev_err(&led->client->dev, "led register err: %d\n", ret);
454 return ret;
455 }
456
457 return 0;
458}
459
460static int lm3692x_probe(struct i2c_client *client,
461 const struct i2c_device_id *id)
462{
463 struct lm3692x_led *led;
464 int ret;
465
466 led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
467 if (!led)
468 return -ENOMEM;
469
470 mutex_init(&led->lock);
471 led->client = client;
472 led->led_dev.brightness_set_blocking = lm3692x_brightness_set;
473 led->model_id = id->driver_data;
474 i2c_set_clientdata(client, led);
475
476 led->regmap = devm_regmap_init_i2c(client, &lm3692x_regmap_config);
477 if (IS_ERR(led->regmap)) {
478 ret = PTR_ERR(led->regmap);
479 dev_err(&client->dev, "Failed to allocate register map: %d\n",
480 ret);
481 return ret;
482 }
483
484 ret = lm3692x_probe_dt(led);
485 if (ret)
486 return ret;
487
488 ret = lm3692x_leds_enable(led);
489 if (ret)
490 return ret;
491
492 return 0;
493}
494
495static int lm3692x_remove(struct i2c_client *client)
496{
497 struct lm3692x_led *led = i2c_get_clientdata(client);
498 int ret;
499
500 ret = lm3692x_leds_disable(led);
501 if (ret)
502 return ret;
503 mutex_destroy(&led->lock);
504
505 return 0;
506}
507
508static const struct i2c_device_id lm3692x_id[] = {
509 { "lm36922", LM36922_MODEL },
510 { "lm36923", LM36923_MODEL },
511 { }
512};
513MODULE_DEVICE_TABLE(i2c, lm3692x_id);
514
515static const struct of_device_id of_lm3692x_leds_match[] = {
516 { .compatible = "ti,lm36922", },
517 { .compatible = "ti,lm36923", },
518 {},
519};
520MODULE_DEVICE_TABLE(of, of_lm3692x_leds_match);
521
522static struct i2c_driver lm3692x_driver = {
523 .driver = {
524 .name = "lm3692x",
525 .of_match_table = of_lm3692x_leds_match,
526 },
527 .probe = lm3692x_probe,
528 .remove = lm3692x_remove,
529 .id_table = lm3692x_id,
530};
531module_i2c_driver(lm3692x_driver);
532
533MODULE_DESCRIPTION("Texas Instruments LM3692X LED driver");
534MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
535MODULE_LICENSE("GPL v2");
536
