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[mirror_ubuntu-bionic-kernel.git] / drivers / leds / leds-lp5521.c
1 /*
2 * LP5521 LED chip driver.
3 *
4 * Copyright (C) 2010 Nokia Corporation
5 * Copyright (C) 2012 Texas Instruments
6 *
7 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
8 * Milo(Woogyom) Kim <milo.kim@ti.com>
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * version 2 as published by the Free Software Foundation.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
22 * 02110-1301 USA
23 */
24
25 #include <linux/delay.h>
26 #include <linux/firmware.h>
27 #include <linux/i2c.h>
28 #include <linux/init.h>
29 #include <linux/leds.h>
30 #include <linux/module.h>
31 #include <linux/mutex.h>
32 #include <linux/platform_data/leds-lp55xx.h>
33 #include <linux/slab.h>
34 #include <linux/of.h>
35
36 #include "leds-lp55xx-common.h"
37
38 #define LP5521_PROGRAM_LENGTH 32
39 #define LP5521_MAX_LEDS 3
40 #define LP5521_CMD_DIRECT 0x3F
41
42 /* Registers */
43 #define LP5521_REG_ENABLE 0x00
44 #define LP5521_REG_OP_MODE 0x01
45 #define LP5521_REG_R_PWM 0x02
46 #define LP5521_REG_G_PWM 0x03
47 #define LP5521_REG_B_PWM 0x04
48 #define LP5521_REG_R_CURRENT 0x05
49 #define LP5521_REG_G_CURRENT 0x06
50 #define LP5521_REG_B_CURRENT 0x07
51 #define LP5521_REG_CONFIG 0x08
52 #define LP5521_REG_STATUS 0x0C
53 #define LP5521_REG_RESET 0x0D
54 #define LP5521_REG_R_PROG_MEM 0x10
55 #define LP5521_REG_G_PROG_MEM 0x30
56 #define LP5521_REG_B_PROG_MEM 0x50
57
58 /* Base register to set LED current */
59 #define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT
60 /* Base register to set the brightness */
61 #define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM
62
63 /* Bits in ENABLE register */
64 #define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */
65 #define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */
66 #define LP5521_EXEC_RUN 0x2A
67 #define LP5521_ENABLE_DEFAULT \
68 (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
69 #define LP5521_ENABLE_RUN_PROGRAM \
70 (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)
71
72 /* CONFIG register */
73 #define LP5521_PWM_HF 0x40 /* PWM: 0 = 256Hz, 1 = 558Hz */
74 #define LP5521_PWRSAVE_EN 0x20 /* 1 = Power save mode */
75 #define LP5521_CP_MODE_OFF 0 /* Charge pump (CP) off */
76 #define LP5521_CP_MODE_BYPASS 8 /* CP forced to bypass mode */
77 #define LP5521_CP_MODE_1X5 0x10 /* CP forced to 1.5x mode */
78 #define LP5521_CP_MODE_AUTO 0x18 /* Automatic mode selection */
79 #define LP5521_R_TO_BATT 0x04 /* R out: 0 = CP, 1 = Vbat */
80 #define LP5521_CLK_INT 0x01 /* Internal clock */
81 #define LP5521_DEFAULT_CFG \
82 (LP5521_PWM_HF | LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO)
83
84 /* Status */
85 #define LP5521_EXT_CLK_USED 0x08
86
87 /* default R channel current register value */
88 #define LP5521_REG_R_CURR_DEFAULT 0xAF
89
90 /* Reset register value */
91 #define LP5521_RESET 0xFF
92
93 /* Program Memory Operations */
94 #define LP5521_MODE_R_M 0x30 /* Operation Mode Register */
95 #define LP5521_MODE_G_M 0x0C
96 #define LP5521_MODE_B_M 0x03
97 #define LP5521_LOAD_R 0x10
98 #define LP5521_LOAD_G 0x04
99 #define LP5521_LOAD_B 0x01
100
101 #define LP5521_R_IS_LOADING(mode) \
102 ((mode & LP5521_MODE_R_M) == LP5521_LOAD_R)
103 #define LP5521_G_IS_LOADING(mode) \
104 ((mode & LP5521_MODE_G_M) == LP5521_LOAD_G)
105 #define LP5521_B_IS_LOADING(mode) \
106 ((mode & LP5521_MODE_B_M) == LP5521_LOAD_B)
107
108 #define LP5521_EXEC_R_M 0x30 /* Enable Register */
109 #define LP5521_EXEC_G_M 0x0C
110 #define LP5521_EXEC_B_M 0x03
111 #define LP5521_EXEC_M 0x3F
112 #define LP5521_RUN_R 0x20
113 #define LP5521_RUN_G 0x08
114 #define LP5521_RUN_B 0x02
115
116 static inline void lp5521_wait_opmode_done(void)
117 {
118 /* operation mode change needs to be longer than 153 us */
119 usleep_range(200, 300);
120 }
121
122 static inline void lp5521_wait_enable_done(void)
123 {
124 /* it takes more 488 us to update ENABLE register */
125 usleep_range(500, 600);
126 }
127
128 static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current)
129 {
130 led->led_current = led_current;
131 lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr,
132 led_current);
133 }
134
135 static void lp5521_load_engine(struct lp55xx_chip *chip)
136 {
137 enum lp55xx_engine_index idx = chip->engine_idx;
138 u8 mask[] = {
139 [LP55XX_ENGINE_1] = LP5521_MODE_R_M,
140 [LP55XX_ENGINE_2] = LP5521_MODE_G_M,
141 [LP55XX_ENGINE_3] = LP5521_MODE_B_M,
142 };
143
144 u8 val[] = {
145 [LP55XX_ENGINE_1] = LP5521_LOAD_R,
146 [LP55XX_ENGINE_2] = LP5521_LOAD_G,
147 [LP55XX_ENGINE_3] = LP5521_LOAD_B,
148 };
149
150 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]);
151
152 lp5521_wait_opmode_done();
153 }
154
155 static void lp5521_stop_all_engines(struct lp55xx_chip *chip)
156 {
157 lp55xx_write(chip, LP5521_REG_OP_MODE, 0);
158 lp5521_wait_opmode_done();
159 }
160
161 static void lp5521_stop_engine(struct lp55xx_chip *chip)
162 {
163 enum lp55xx_engine_index idx = chip->engine_idx;
164 u8 mask[] = {
165 [LP55XX_ENGINE_1] = LP5521_MODE_R_M,
166 [LP55XX_ENGINE_2] = LP5521_MODE_G_M,
167 [LP55XX_ENGINE_3] = LP5521_MODE_B_M,
168 };
169
170 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], 0);
171
172 lp5521_wait_opmode_done();
173 }
174
175 static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
176 {
177 int ret;
178 u8 mode;
179 u8 exec;
180
181 /* stop engine */
182 if (!start) {
183 lp5521_stop_engine(chip);
184 lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
185 lp5521_wait_opmode_done();
186 return;
187 }
188
189 /*
190 * To run the engine,
191 * operation mode and enable register should updated at the same time
192 */
193
194 ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode);
195 if (ret)
196 return;
197
198 ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec);
199 if (ret)
200 return;
201
202 /* change operation mode to RUN only when each engine is loading */
203 if (LP5521_R_IS_LOADING(mode)) {
204 mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R;
205 exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R;
206 }
207
208 if (LP5521_G_IS_LOADING(mode)) {
209 mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G;
210 exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G;
211 }
212
213 if (LP5521_B_IS_LOADING(mode)) {
214 mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B;
215 exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B;
216 }
217
218 lp55xx_write(chip, LP5521_REG_OP_MODE, mode);
219 lp5521_wait_opmode_done();
220
221 lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec);
222 lp5521_wait_enable_done();
223 }
224
225 static int lp5521_update_program_memory(struct lp55xx_chip *chip,
226 const u8 *data, size_t size)
227 {
228 enum lp55xx_engine_index idx = chip->engine_idx;
229 u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
230 u8 addr[] = {
231 [LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM,
232 [LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM,
233 [LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM,
234 };
235 unsigned cmd;
236 char c[3];
237 int nrchars;
238 int ret;
239 int offset = 0;
240 int i = 0;
241
242 while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) {
243 /* separate sscanfs because length is working only for %s */
244 ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
245 if (ret != 1)
246 goto err;
247
248 ret = sscanf(c, "%2x", &cmd);
249 if (ret != 1)
250 goto err;
251
252 pattern[i] = (u8)cmd;
253 offset += nrchars;
254 i++;
255 }
256
257 /* Each instruction is 16bit long. Check that length is even */
258 if (i % 2)
259 goto err;
260
261 for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) {
262 ret = lp55xx_write(chip, addr[idx] + i, pattern[i]);
263 if (ret)
264 return -EINVAL;
265 }
266
267 return size;
268
269 err:
270 dev_err(&chip->cl->dev, "wrong pattern format\n");
271 return -EINVAL;
272 }
273
274 static void lp5521_firmware_loaded(struct lp55xx_chip *chip)
275 {
276 const struct firmware *fw = chip->fw;
277
278 if (fw->size > LP5521_PROGRAM_LENGTH) {
279 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
280 fw->size);
281 return;
282 }
283
284 /*
285 * Program momery sequence
286 * 1) set engine mode to "LOAD"
287 * 2) write firmware data into program memory
288 */
289
290 lp5521_load_engine(chip);
291 lp5521_update_program_memory(chip, fw->data, fw->size);
292 }
293
294 static int lp5521_post_init_device(struct lp55xx_chip *chip)
295 {
296 int ret;
297 u8 val;
298
299 /*
300 * Make sure that the chip is reset by reading back the r channel
301 * current reg. This is dummy read is required on some platforms -
302 * otherwise further access to the R G B channels in the
303 * LP5521_REG_ENABLE register will not have any effect - strange!
304 */
305 ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
306 if (ret) {
307 dev_err(&chip->cl->dev, "error in resetting chip\n");
308 return ret;
309 }
310 if (val != LP5521_REG_R_CURR_DEFAULT) {
311 dev_err(&chip->cl->dev,
312 "unexpected data in register (expected 0x%x got 0x%x)\n",
313 LP5521_REG_R_CURR_DEFAULT, val);
314 ret = -EINVAL;
315 return ret;
316 }
317 usleep_range(10000, 20000);
318
319 /* Set all PWMs to direct control mode */
320 ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
321
322 /* Update configuration for the clock setting */
323 val = LP5521_DEFAULT_CFG;
324 if (!lp55xx_is_extclk_used(chip))
325 val |= LP5521_CLK_INT;
326
327 ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
328 if (ret)
329 return ret;
330
331 /* Initialize all channels PWM to zero -> leds off */
332 lp55xx_write(chip, LP5521_REG_R_PWM, 0);
333 lp55xx_write(chip, LP5521_REG_G_PWM, 0);
334 lp55xx_write(chip, LP5521_REG_B_PWM, 0);
335
336 /* Set engines are set to run state when OP_MODE enables engines */
337 ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
338 if (ret)
339 return ret;
340
341 lp5521_wait_enable_done();
342
343 return 0;
344 }
345
346 static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf)
347 {
348 struct lp55xx_platform_data *pdata = chip->pdata;
349 int ret;
350 u8 status;
351
352 ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);
353 if (ret < 0)
354 return ret;
355
356 if (pdata->clock_mode != LP55XX_CLOCK_EXT)
357 return 0;
358
359 /* Check that ext clock is really in use if requested */
360 if ((status & LP5521_EXT_CLK_USED) == 0)
361 return -EIO;
362
363 return 0;
364 }
365
366 static void lp5521_led_brightness_work(struct work_struct *work)
367 {
368 struct lp55xx_led *led = container_of(work, struct lp55xx_led,
369 brightness_work);
370 struct lp55xx_chip *chip = led->chip;
371
372 mutex_lock(&chip->lock);
373 lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr,
374 led->brightness);
375 mutex_unlock(&chip->lock);
376 }
377
378 static ssize_t show_engine_mode(struct device *dev,
379 struct device_attribute *attr,
380 char *buf, int nr)
381 {
382 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
383 struct lp55xx_chip *chip = led->chip;
384 enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
385
386 switch (mode) {
387 case LP55XX_ENGINE_RUN:
388 return sprintf(buf, "run\n");
389 case LP55XX_ENGINE_LOAD:
390 return sprintf(buf, "load\n");
391 case LP55XX_ENGINE_DISABLED:
392 default:
393 return sprintf(buf, "disabled\n");
394 }
395 }
396 show_mode(1)
397 show_mode(2)
398 show_mode(3)
399
400 static ssize_t store_engine_mode(struct device *dev,
401 struct device_attribute *attr,
402 const char *buf, size_t len, int nr)
403 {
404 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
405 struct lp55xx_chip *chip = led->chip;
406 struct lp55xx_engine *engine = &chip->engines[nr - 1];
407
408 mutex_lock(&chip->lock);
409
410 chip->engine_idx = nr;
411
412 if (!strncmp(buf, "run", 3)) {
413 lp5521_run_engine(chip, true);
414 engine->mode = LP55XX_ENGINE_RUN;
415 } else if (!strncmp(buf, "load", 4)) {
416 lp5521_stop_engine(chip);
417 lp5521_load_engine(chip);
418 engine->mode = LP55XX_ENGINE_LOAD;
419 } else if (!strncmp(buf, "disabled", 8)) {
420 lp5521_stop_engine(chip);
421 engine->mode = LP55XX_ENGINE_DISABLED;
422 }
423
424 mutex_unlock(&chip->lock);
425
426 return len;
427 }
428 store_mode(1)
429 store_mode(2)
430 store_mode(3)
431
432 static ssize_t store_engine_load(struct device *dev,
433 struct device_attribute *attr,
434 const char *buf, size_t len, int nr)
435 {
436 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
437 struct lp55xx_chip *chip = led->chip;
438 int ret;
439
440 mutex_lock(&chip->lock);
441
442 chip->engine_idx = nr;
443 lp5521_load_engine(chip);
444 ret = lp5521_update_program_memory(chip, buf, len);
445
446 mutex_unlock(&chip->lock);
447
448 return ret;
449 }
450 store_load(1)
451 store_load(2)
452 store_load(3)
453
454 static ssize_t lp5521_selftest(struct device *dev,
455 struct device_attribute *attr,
456 char *buf)
457 {
458 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
459 struct lp55xx_chip *chip = led->chip;
460 int ret;
461
462 mutex_lock(&chip->lock);
463 ret = lp5521_run_selftest(chip, buf);
464 mutex_unlock(&chip->lock);
465
466 return scnprintf(buf, PAGE_SIZE, "%s\n", ret ? "FAIL" : "OK");
467 }
468
469 /* device attributes */
470 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
471 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
472 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
473 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
474 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
475 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
476 static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);
477
478 static struct attribute *lp5521_attributes[] = {
479 &dev_attr_engine1_mode.attr,
480 &dev_attr_engine2_mode.attr,
481 &dev_attr_engine3_mode.attr,
482 &dev_attr_engine1_load.attr,
483 &dev_attr_engine2_load.attr,
484 &dev_attr_engine3_load.attr,
485 &dev_attr_selftest.attr,
486 NULL
487 };
488
489 static const struct attribute_group lp5521_group = {
490 .attrs = lp5521_attributes,
491 };
492
493 /* Chip specific configurations */
494 static struct lp55xx_device_config lp5521_cfg = {
495 .reset = {
496 .addr = LP5521_REG_RESET,
497 .val = LP5521_RESET,
498 },
499 .enable = {
500 .addr = LP5521_REG_ENABLE,
501 .val = LP5521_ENABLE_DEFAULT,
502 },
503 .max_channel = LP5521_MAX_LEDS,
504 .post_init_device = lp5521_post_init_device,
505 .brightness_work_fn = lp5521_led_brightness_work,
506 .set_led_current = lp5521_set_led_current,
507 .firmware_cb = lp5521_firmware_loaded,
508 .run_engine = lp5521_run_engine,
509 .dev_attr_group = &lp5521_group,
510 };
511
512 static int lp5521_probe(struct i2c_client *client,
513 const struct i2c_device_id *id)
514 {
515 int ret;
516 struct lp55xx_chip *chip;
517 struct lp55xx_led *led;
518 struct lp55xx_platform_data *pdata;
519 struct device_node *np = client->dev.of_node;
520
521 if (!dev_get_platdata(&client->dev)) {
522 if (np) {
523 ret = lp55xx_of_populate_pdata(&client->dev, np);
524 if (ret < 0)
525 return ret;
526 } else {
527 dev_err(&client->dev, "no platform data\n");
528 return -EINVAL;
529 }
530 }
531 pdata = dev_get_platdata(&client->dev);
532
533 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
534 if (!chip)
535 return -ENOMEM;
536
537 led = devm_kzalloc(&client->dev,
538 sizeof(*led) * pdata->num_channels, GFP_KERNEL);
539 if (!led)
540 return -ENOMEM;
541
542 chip->cl = client;
543 chip->pdata = pdata;
544 chip->cfg = &lp5521_cfg;
545
546 mutex_init(&chip->lock);
547
548 i2c_set_clientdata(client, led);
549
550 ret = lp55xx_init_device(chip);
551 if (ret)
552 goto err_init;
553
554 dev_info(&client->dev, "%s programmable led chip found\n", id->name);
555
556 ret = lp55xx_register_leds(led, chip);
557 if (ret)
558 goto err_register_leds;
559
560 ret = lp55xx_register_sysfs(chip);
561 if (ret) {
562 dev_err(&client->dev, "registering sysfs failed\n");
563 goto err_register_sysfs;
564 }
565
566 return 0;
567
568 err_register_sysfs:
569 lp55xx_unregister_leds(led, chip);
570 err_register_leds:
571 lp55xx_deinit_device(chip);
572 err_init:
573 return ret;
574 }
575
576 static int lp5521_remove(struct i2c_client *client)
577 {
578 struct lp55xx_led *led = i2c_get_clientdata(client);
579 struct lp55xx_chip *chip = led->chip;
580
581 lp5521_stop_all_engines(chip);
582 lp55xx_unregister_sysfs(chip);
583 lp55xx_unregister_leds(led, chip);
584 lp55xx_deinit_device(chip);
585
586 return 0;
587 }
588
589 static const struct i2c_device_id lp5521_id[] = {
590 { "lp5521", 0 }, /* Three channel chip */
591 { }
592 };
593 MODULE_DEVICE_TABLE(i2c, lp5521_id);
594
595 #ifdef CONFIG_OF
596 static const struct of_device_id of_lp5521_leds_match[] = {
597 { .compatible = "national,lp5521", },
598 {},
599 };
600
601 MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);
602 #endif
603 static struct i2c_driver lp5521_driver = {
604 .driver = {
605 .name = "lp5521",
606 .of_match_table = of_match_ptr(of_lp5521_leds_match),
607 },
608 .probe = lp5521_probe,
609 .remove = lp5521_remove,
610 .id_table = lp5521_id,
611 };
612
613 module_i2c_driver(lp5521_driver);
614
615 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
616 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
617 MODULE_DESCRIPTION("LP5521 LED engine");
618 MODULE_LICENSE("GPL v2");