Merge remote-tracking branch 'stable/linux-5.15.y' into rpi-5.15.y
[platform/kernel/linux-rpi.git] / drivers / leds / leds-lp5521.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * LP5521 LED chip driver.
4  *
5  * Copyright (C) 2010 Nokia Corporation
6  * Copyright (C) 2012 Texas Instruments
7  *
8  * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
9  *          Milo(Woogyom) Kim <milo.kim@ti.com>
10  */
11
12 #include <linux/delay.h>
13 #include <linux/firmware.h>
14 #include <linux/i2c.h>
15 #include <linux/leds.h>
16 #include <linux/module.h>
17 #include <linux/mutex.h>
18 #include <linux/platform_data/leds-lp55xx.h>
19 #include <linux/slab.h>
20 #include <linux/of.h>
21
22 #include "leds-lp55xx-common.h"
23
24 #define LP5521_PROGRAM_LENGTH           32
25 #define LP5521_MAX_LEDS                 3
26 #define LP5521_CMD_DIRECT               0x3F
27
28 /* Registers */
29 #define LP5521_REG_ENABLE               0x00
30 #define LP5521_REG_OP_MODE              0x01
31 #define LP5521_REG_R_PWM                0x02
32 #define LP5521_REG_G_PWM                0x03
33 #define LP5521_REG_B_PWM                0x04
34 #define LP5521_REG_R_CURRENT            0x05
35 #define LP5521_REG_G_CURRENT            0x06
36 #define LP5521_REG_B_CURRENT            0x07
37 #define LP5521_REG_CONFIG               0x08
38 #define LP5521_REG_STATUS               0x0C
39 #define LP5521_REG_RESET                0x0D
40 #define LP5521_REG_R_PROG_MEM           0x10
41 #define LP5521_REG_G_PROG_MEM           0x30
42 #define LP5521_REG_B_PROG_MEM           0x50
43
44 /* Base register to set LED current */
45 #define LP5521_REG_LED_CURRENT_BASE     LP5521_REG_R_CURRENT
46 /* Base register to set the brightness */
47 #define LP5521_REG_LED_PWM_BASE         LP5521_REG_R_PWM
48
49 /* Bits in ENABLE register */
50 #define LP5521_MASTER_ENABLE            0x40    /* Chip master enable */
51 #define LP5521_LOGARITHMIC_PWM          0x80    /* Logarithmic PWM adjustment */
52 #define LP5521_EXEC_RUN                 0x2A
53 #define LP5521_ENABLE_DEFAULT   \
54         (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
55 #define LP5521_ENABLE_RUN_PROGRAM       \
56         (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)
57
58 /* CONFIG register */
59 #define LP5521_PWM_HF                   0x40    /* PWM: 0 = 256Hz, 1 = 558Hz */
60 #define LP5521_PWRSAVE_EN               0x20    /* 1 = Power save mode */
61 #define LP5521_CP_MODE_OFF              0       /* Charge pump (CP) off */
62 #define LP5521_CP_MODE_BYPASS           8       /* CP forced to bypass mode */
63 #define LP5521_CP_MODE_1X5              0x10    /* CP forced to 1.5x mode */
64 #define LP5521_CP_MODE_AUTO             0x18    /* Automatic mode selection */
65 #define LP5521_R_TO_BATT                0x04    /* R out: 0 = CP, 1 = Vbat */
66 #define LP5521_CLK_INT                  0x01    /* Internal clock */
67 #define LP5521_DEFAULT_CFG              \
68         (LP5521_PWM_HF | LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO)
69
70 /* Status */
71 #define LP5521_EXT_CLK_USED             0x08
72
73 /* default R channel current register value */
74 #define LP5521_REG_R_CURR_DEFAULT       0xAF
75
76 /* Reset register value */
77 #define LP5521_RESET                    0xFF
78
79 /* Program Memory Operations */
80 #define LP5521_MODE_R_M                 0x30    /* Operation Mode Register */
81 #define LP5521_MODE_G_M                 0x0C
82 #define LP5521_MODE_B_M                 0x03
83 #define LP5521_LOAD_R                   0x10
84 #define LP5521_LOAD_G                   0x04
85 #define LP5521_LOAD_B                   0x01
86
87 #define LP5521_R_IS_LOADING(mode)       \
88         ((mode & LP5521_MODE_R_M) == LP5521_LOAD_R)
89 #define LP5521_G_IS_LOADING(mode)       \
90         ((mode & LP5521_MODE_G_M) == LP5521_LOAD_G)
91 #define LP5521_B_IS_LOADING(mode)       \
92         ((mode & LP5521_MODE_B_M) == LP5521_LOAD_B)
93
94 #define LP5521_EXEC_R_M                 0x30    /* Enable Register */
95 #define LP5521_EXEC_G_M                 0x0C
96 #define LP5521_EXEC_B_M                 0x03
97 #define LP5521_EXEC_M                   0x3F
98 #define LP5521_RUN_R                    0x20
99 #define LP5521_RUN_G                    0x08
100 #define LP5521_RUN_B                    0x02
101
102 static inline void lp5521_wait_opmode_done(void)
103 {
104         /* operation mode change needs to be longer than 153 us */
105         usleep_range(200, 300);
106 }
107
108 static inline void lp5521_wait_enable_done(void)
109 {
110         /* it takes more 488 us to update ENABLE register */
111         usleep_range(500, 600);
112 }
113
114 static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current)
115 {
116         led->led_current = led_current;
117         lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr,
118                 led_current);
119 }
120
121 static void lp5521_load_engine(struct lp55xx_chip *chip)
122 {
123         enum lp55xx_engine_index idx = chip->engine_idx;
124         static const u8 mask[] = {
125                 [LP55XX_ENGINE_1] = LP5521_MODE_R_M,
126                 [LP55XX_ENGINE_2] = LP5521_MODE_G_M,
127                 [LP55XX_ENGINE_3] = LP5521_MODE_B_M,
128         };
129
130         static const u8 val[] = {
131                 [LP55XX_ENGINE_1] = LP5521_LOAD_R,
132                 [LP55XX_ENGINE_2] = LP5521_LOAD_G,
133                 [LP55XX_ENGINE_3] = LP5521_LOAD_B,
134         };
135
136         lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]);
137
138         lp5521_wait_opmode_done();
139 }
140
141 static void lp5521_stop_all_engines(struct lp55xx_chip *chip)
142 {
143         lp55xx_write(chip, LP5521_REG_OP_MODE, 0);
144         lp5521_wait_opmode_done();
145 }
146
147 static void lp5521_stop_engine(struct lp55xx_chip *chip)
148 {
149         enum lp55xx_engine_index idx = chip->engine_idx;
150         static const u8 mask[] = {
151                 [LP55XX_ENGINE_1] = LP5521_MODE_R_M,
152                 [LP55XX_ENGINE_2] = LP5521_MODE_G_M,
153                 [LP55XX_ENGINE_3] = LP5521_MODE_B_M,
154         };
155
156         lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], 0);
157
158         lp5521_wait_opmode_done();
159 }
160
161 static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
162 {
163         int ret;
164         u8 mode;
165         u8 exec;
166
167         /* stop engine */
168         if (!start) {
169                 lp5521_stop_engine(chip);
170                 lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
171                 lp5521_wait_opmode_done();
172                 return;
173         }
174
175         /*
176          * To run the engine,
177          * operation mode and enable register should updated at the same time
178          */
179
180         ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode);
181         if (ret)
182                 return;
183
184         ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec);
185         if (ret)
186                 return;
187
188         /* change operation mode to RUN only when each engine is loading */
189         if (LP5521_R_IS_LOADING(mode)) {
190                 mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R;
191                 exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R;
192         }
193
194         if (LP5521_G_IS_LOADING(mode)) {
195                 mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G;
196                 exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G;
197         }
198
199         if (LP5521_B_IS_LOADING(mode)) {
200                 mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B;
201                 exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B;
202         }
203
204         lp55xx_write(chip, LP5521_REG_OP_MODE, mode);
205         lp5521_wait_opmode_done();
206
207         lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec);
208         lp5521_wait_enable_done();
209 }
210
211 static int lp5521_update_program_memory(struct lp55xx_chip *chip,
212                                         const u8 *data, size_t size)
213 {
214         enum lp55xx_engine_index idx = chip->engine_idx;
215         u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
216         static const u8 addr[] = {
217                 [LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM,
218                 [LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM,
219                 [LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM,
220         };
221         unsigned cmd;
222         char c[3];
223         int nrchars;
224         int ret;
225         int offset = 0;
226         int i = 0;
227
228         while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) {
229                 /* separate sscanfs because length is working only for %s */
230                 ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
231                 if (ret != 1)
232                         goto err;
233
234                 ret = sscanf(c, "%2x", &cmd);
235                 if (ret != 1)
236                         goto err;
237
238                 pattern[i] = (u8)cmd;
239                 offset += nrchars;
240                 i++;
241         }
242
243         /* Each instruction is 16bit long. Check that length is even */
244         if (i % 2)
245                 goto err;
246
247         for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) {
248                 ret = lp55xx_write(chip, addr[idx] + i, pattern[i]);
249                 if (ret)
250                         return -EINVAL;
251         }
252
253         return size;
254
255 err:
256         dev_err(&chip->cl->dev, "wrong pattern format\n");
257         return -EINVAL;
258 }
259
260 static void lp5521_firmware_loaded(struct lp55xx_chip *chip)
261 {
262         const struct firmware *fw = chip->fw;
263
264         if (fw->size > LP5521_PROGRAM_LENGTH) {
265                 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
266                         fw->size);
267                 return;
268         }
269
270         /*
271          * Program memory sequence
272          *  1) set engine mode to "LOAD"
273          *  2) write firmware data into program memory
274          */
275
276         lp5521_load_engine(chip);
277         lp5521_update_program_memory(chip, fw->data, fw->size);
278 }
279
280 static int lp5521_post_init_device(struct lp55xx_chip *chip)
281 {
282         int ret;
283         u8 val;
284
285         /*
286          * Make sure that the chip is reset by reading back the r channel
287          * current reg. This is dummy read is required on some platforms -
288          * otherwise further access to the R G B channels in the
289          * LP5521_REG_ENABLE register will not have any effect - strange!
290          */
291         ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
292         if (ret) {
293                 dev_err(&chip->cl->dev, "error in resetting chip\n");
294                 return ret;
295         }
296         if (val != LP5521_REG_R_CURR_DEFAULT) {
297                 dev_err(&chip->cl->dev,
298                         "unexpected data in register (expected 0x%x got 0x%x)\n",
299                         LP5521_REG_R_CURR_DEFAULT, val);
300                 ret = -EINVAL;
301                 return ret;
302         }
303         usleep_range(10000, 20000);
304
305         /* Set all PWMs to direct control mode */
306         ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
307
308         /* Update configuration for the clock setting */
309         val = LP5521_DEFAULT_CFG;
310         if (!lp55xx_is_extclk_used(chip))
311                 val |= LP5521_CLK_INT;
312
313         ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
314         if (ret)
315                 return ret;
316
317         /* Initialize all channels PWM to zero -> leds off */
318         lp55xx_write(chip, LP5521_REG_R_PWM, 0);
319         lp55xx_write(chip, LP5521_REG_G_PWM, 0);
320         lp55xx_write(chip, LP5521_REG_B_PWM, 0);
321
322         /* Set engines are set to run state when OP_MODE enables engines */
323         ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
324         if (ret)
325                 return ret;
326
327         lp5521_wait_enable_done();
328
329         return 0;
330 }
331
332 static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf)
333 {
334         struct lp55xx_platform_data *pdata = chip->pdata;
335         int ret;
336         u8 status;
337
338         ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);
339         if (ret < 0)
340                 return ret;
341
342         if (pdata->clock_mode != LP55XX_CLOCK_EXT)
343                 return 0;
344
345         /* Check that ext clock is really in use if requested */
346         if  ((status & LP5521_EXT_CLK_USED) == 0)
347                 return -EIO;
348
349         return 0;
350 }
351
352 static int lp5521_multicolor_brightness(struct lp55xx_led *led)
353 {
354         struct lp55xx_chip *chip = led->chip;
355         int ret;
356         int i;
357
358         mutex_lock(&chip->lock);
359         for (i = 0; i < led->mc_cdev.num_colors; i++) {
360                 ret = lp55xx_write(chip,
361                                    LP5521_REG_LED_PWM_BASE +
362                                    led->mc_cdev.subled_info[i].channel,
363                                    led->mc_cdev.subled_info[i].brightness);
364                 if (ret)
365                         break;
366         }
367         mutex_unlock(&chip->lock);
368         return ret;
369 }
370
371 static int lp5521_led_brightness(struct lp55xx_led *led)
372 {
373         struct lp55xx_chip *chip = led->chip;
374         int ret;
375
376         mutex_lock(&chip->lock);
377         ret = lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr,
378                 led->brightness);
379         mutex_unlock(&chip->lock);
380
381         return ret;
382 }
383
384 static ssize_t show_engine_mode(struct device *dev,
385                                 struct device_attribute *attr,
386                                 char *buf, int nr)
387 {
388         struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
389         struct lp55xx_chip *chip = led->chip;
390         enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
391
392         switch (mode) {
393         case LP55XX_ENGINE_RUN:
394                 return sprintf(buf, "run\n");
395         case LP55XX_ENGINE_LOAD:
396                 return sprintf(buf, "load\n");
397         case LP55XX_ENGINE_DISABLED:
398         default:
399                 return sprintf(buf, "disabled\n");
400         }
401 }
402 show_mode(1)
403 show_mode(2)
404 show_mode(3)
405
406 static ssize_t store_engine_mode(struct device *dev,
407                                  struct device_attribute *attr,
408                                  const char *buf, size_t len, int nr)
409 {
410         struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
411         struct lp55xx_chip *chip = led->chip;
412         struct lp55xx_engine *engine = &chip->engines[nr - 1];
413
414         mutex_lock(&chip->lock);
415
416         chip->engine_idx = nr;
417
418         if (!strncmp(buf, "run", 3)) {
419                 lp5521_run_engine(chip, true);
420                 engine->mode = LP55XX_ENGINE_RUN;
421         } else if (!strncmp(buf, "load", 4)) {
422                 lp5521_stop_engine(chip);
423                 lp5521_load_engine(chip);
424                 engine->mode = LP55XX_ENGINE_LOAD;
425         } else if (!strncmp(buf, "disabled", 8)) {
426                 lp5521_stop_engine(chip);
427                 engine->mode = LP55XX_ENGINE_DISABLED;
428         }
429
430         mutex_unlock(&chip->lock);
431
432         return len;
433 }
434 store_mode(1)
435 store_mode(2)
436 store_mode(3)
437
438 static ssize_t store_engine_load(struct device *dev,
439                              struct device_attribute *attr,
440                              const char *buf, size_t len, int nr)
441 {
442         struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
443         struct lp55xx_chip *chip = led->chip;
444         int ret;
445
446         mutex_lock(&chip->lock);
447
448         chip->engine_idx = nr;
449         lp5521_load_engine(chip);
450         ret = lp5521_update_program_memory(chip, buf, len);
451
452         mutex_unlock(&chip->lock);
453
454         return ret;
455 }
456 store_load(1)
457 store_load(2)
458 store_load(3)
459
460 static ssize_t lp5521_selftest(struct device *dev,
461                                struct device_attribute *attr,
462                                char *buf)
463 {
464         struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
465         struct lp55xx_chip *chip = led->chip;
466         int ret;
467
468         mutex_lock(&chip->lock);
469         ret = lp5521_run_selftest(chip, buf);
470         mutex_unlock(&chip->lock);
471
472         return scnprintf(buf, PAGE_SIZE, "%s\n", ret ? "FAIL" : "OK");
473 }
474
475 /* device attributes */
476 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
477 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
478 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
479 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
480 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
481 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
482 static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);
483
484 static struct attribute *lp5521_attributes[] = {
485         &dev_attr_engine1_mode.attr,
486         &dev_attr_engine2_mode.attr,
487         &dev_attr_engine3_mode.attr,
488         &dev_attr_engine1_load.attr,
489         &dev_attr_engine2_load.attr,
490         &dev_attr_engine3_load.attr,
491         &dev_attr_selftest.attr,
492         NULL
493 };
494
495 static const struct attribute_group lp5521_group = {
496         .attrs = lp5521_attributes,
497 };
498
499 /* Chip specific configurations */
500 static struct lp55xx_device_config lp5521_cfg = {
501         .reset = {
502                 .addr = LP5521_REG_RESET,
503                 .val  = LP5521_RESET,
504         },
505         .enable = {
506                 .addr = LP5521_REG_ENABLE,
507                 .val  = LP5521_ENABLE_DEFAULT,
508         },
509         .max_channel  = LP5521_MAX_LEDS,
510         .post_init_device   = lp5521_post_init_device,
511         .brightness_fn      = lp5521_led_brightness,
512         .multicolor_brightness_fn = lp5521_multicolor_brightness,
513         .set_led_current    = lp5521_set_led_current,
514         .firmware_cb        = lp5521_firmware_loaded,
515         .run_engine         = lp5521_run_engine,
516         .dev_attr_group     = &lp5521_group,
517 };
518
519 static int lp5521_probe(struct i2c_client *client,
520                         const struct i2c_device_id *id)
521 {
522         int ret;
523         struct lp55xx_chip *chip;
524         struct lp55xx_led *led;
525         struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
526         struct device_node *np = dev_of_node(&client->dev);
527
528         chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
529         if (!chip)
530                 return -ENOMEM;
531
532         chip->cfg = &lp5521_cfg;
533
534         if (!pdata) {
535                 if (np) {
536                         pdata = lp55xx_of_populate_pdata(&client->dev, np,
537                                                          chip);
538                         if (IS_ERR(pdata))
539                                 return PTR_ERR(pdata);
540                 } else {
541                         dev_err(&client->dev, "no platform data\n");
542                         return -EINVAL;
543                 }
544         }
545
546         led = devm_kcalloc(&client->dev,
547                         pdata->num_channels, sizeof(*led), GFP_KERNEL);
548         if (!led)
549                 return -ENOMEM;
550
551         chip->cl = client;
552         chip->pdata = pdata;
553
554         mutex_init(&chip->lock);
555
556         i2c_set_clientdata(client, led);
557
558         ret = lp55xx_init_device(chip);
559         if (ret)
560                 goto err_init;
561
562         dev_info(&client->dev, "%s programmable led chip found\n", id->name);
563
564         ret = lp55xx_register_leds(led, chip);
565         if (ret)
566                 goto err_out;
567
568         ret = lp55xx_register_sysfs(chip);
569         if (ret) {
570                 dev_err(&client->dev, "registering sysfs failed\n");
571                 goto err_out;
572         }
573
574         return 0;
575
576 err_out:
577         lp55xx_deinit_device(chip);
578 err_init:
579         return ret;
580 }
581
582 static int lp5521_remove(struct i2c_client *client)
583 {
584         struct lp55xx_led *led = i2c_get_clientdata(client);
585         struct lp55xx_chip *chip = led->chip;
586
587         lp5521_stop_all_engines(chip);
588         lp55xx_unregister_sysfs(chip);
589         lp55xx_deinit_device(chip);
590
591         return 0;
592 }
593
594 static const struct i2c_device_id lp5521_id[] = {
595         { "lp5521", 0 }, /* Three channel chip */
596         { }
597 };
598 MODULE_DEVICE_TABLE(i2c, lp5521_id);
599
600 #ifdef CONFIG_OF
601 static const struct of_device_id of_lp5521_leds_match[] = {
602         { .compatible = "national,lp5521", },
603         {},
604 };
605
606 MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);
607 #endif
608 static struct i2c_driver lp5521_driver = {
609         .driver = {
610                 .name   = "lp5521",
611                 .of_match_table = of_match_ptr(of_lp5521_leds_match),
612         },
613         .probe          = lp5521_probe,
614         .remove         = lp5521_remove,
615         .id_table       = lp5521_id,
616 };
617
618 module_i2c_driver(lp5521_driver);
619
620 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
621 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
622 MODULE_DESCRIPTION("LP5521 LED engine");
623 MODULE_LICENSE("GPL v2");