tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * LP5562 LED driver
3 *
4 * Copyright (C) 2013 Texas Instruments
5 *
6 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/delay.h>
14#include <linux/firmware.h>
15#include <linux/i2c.h>
16#include <linux/init.h>
17#include <linux/leds.h>
18#include <linux/module.h>
19#include <linux/mutex.h>
20#include <linux/of.h>
21#include <linux/platform_data/leds-lp55xx.h>
22#include <linux/slab.h>
23
24#include "leds-lp55xx-common.h"
25
26#define LP5562_PROGRAM_LENGTH 32
27#define LP5562_MAX_LEDS 4
28
29/* ENABLE Register 00h */
30#define LP5562_REG_ENABLE 0x00
31#define LP5562_EXEC_ENG1_M 0x30
32#define LP5562_EXEC_ENG2_M 0x0C
33#define LP5562_EXEC_ENG3_M 0x03
34#define LP5562_EXEC_M 0x3F
35#define LP5562_MASTER_ENABLE 0x40 /* Chip master enable */
36#define LP5562_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */
37#define LP5562_EXEC_RUN 0x2A
38#define LP5562_ENABLE_DEFAULT \
39 (LP5562_MASTER_ENABLE | LP5562_LOGARITHMIC_PWM)
40#define LP5562_ENABLE_RUN_PROGRAM \
41 (LP5562_ENABLE_DEFAULT | LP5562_EXEC_RUN)
42
43/* OPMODE Register 01h */
44#define LP5562_REG_OP_MODE 0x01
45#define LP5562_MODE_ENG1_M 0x30
46#define LP5562_MODE_ENG2_M 0x0C
47#define LP5562_MODE_ENG3_M 0x03
48#define LP5562_LOAD_ENG1 0x10
49#define LP5562_LOAD_ENG2 0x04
50#define LP5562_LOAD_ENG3 0x01
51#define LP5562_RUN_ENG1 0x20
52#define LP5562_RUN_ENG2 0x08
53#define LP5562_RUN_ENG3 0x02
54#define LP5562_ENG1_IS_LOADING(mode) \
55 ((mode & LP5562_MODE_ENG1_M) == LP5562_LOAD_ENG1)
56#define LP5562_ENG2_IS_LOADING(mode) \
57 ((mode & LP5562_MODE_ENG2_M) == LP5562_LOAD_ENG2)
58#define LP5562_ENG3_IS_LOADING(mode) \
59 ((mode & LP5562_MODE_ENG3_M) == LP5562_LOAD_ENG3)
60
61/* BRIGHTNESS Registers */
62#define LP5562_REG_R_PWM 0x04
63#define LP5562_REG_G_PWM 0x03
64#define LP5562_REG_B_PWM 0x02
65#define LP5562_REG_W_PWM 0x0E
66
67/* CURRENT Registers */
68#define LP5562_REG_R_CURRENT 0x07
69#define LP5562_REG_G_CURRENT 0x06
70#define LP5562_REG_B_CURRENT 0x05
71#define LP5562_REG_W_CURRENT 0x0F
72
73/* CONFIG Register 08h */
74#define LP5562_REG_CONFIG 0x08
75#define LP5562_PWM_HF 0x40
76#define LP5562_PWRSAVE_EN 0x20
77#define LP5562_CLK_INT 0x01 /* Internal clock */
78#define LP5562_DEFAULT_CFG (LP5562_PWM_HF | LP5562_PWRSAVE_EN)
79
80/* RESET Register 0Dh */
81#define LP5562_REG_RESET 0x0D
82#define LP5562_RESET 0xFF
83
84/* PROGRAM ENGINE Registers */
85#define LP5562_REG_PROG_MEM_ENG1 0x10
86#define LP5562_REG_PROG_MEM_ENG2 0x30
87#define LP5562_REG_PROG_MEM_ENG3 0x50
88
89/* LEDMAP Register 70h */
90#define LP5562_REG_ENG_SEL 0x70
91#define LP5562_ENG_SEL_PWM 0
92#define LP5562_ENG_FOR_RGB_M 0x3F
93#define LP5562_ENG_SEL_RGB 0x1B /* R:ENG1, G:ENG2, B:ENG3 */
94#define LP5562_ENG_FOR_W_M 0xC0
95#define LP5562_ENG1_FOR_W 0x40 /* W:ENG1 */
96#define LP5562_ENG2_FOR_W 0x80 /* W:ENG2 */
97#define LP5562_ENG3_FOR_W 0xC0 /* W:ENG3 */
98
99/* Program Commands */
100#define LP5562_CMD_DISABLE 0x00
101#define LP5562_CMD_LOAD 0x15
102#define LP5562_CMD_RUN 0x2A
103#define LP5562_CMD_DIRECT 0x3F
104#define LP5562_PATTERN_OFF 0
105
106static inline void lp5562_wait_opmode_done(void)
107{
108 /* operation mode change needs to be longer than 153 us */
109 usleep_range(200, 300);
110}
111
112static inline void lp5562_wait_enable_done(void)
113{
114 /* it takes more 488 us to update ENABLE register */
115 usleep_range(500, 600);
116}
117
118static void lp5562_set_led_current(struct lp55xx_led *led, u8 led_current)
119{
120 u8 addr[] = {
121 LP5562_REG_R_CURRENT,
122 LP5562_REG_G_CURRENT,
123 LP5562_REG_B_CURRENT,
124 LP5562_REG_W_CURRENT,
125 };
126
127 led->led_current = led_current;
128 lp55xx_write(led->chip, addr[led->chan_nr], led_current);
129}
130
131static void lp5562_load_engine(struct lp55xx_chip *chip)
132{
133 enum lp55xx_engine_index idx = chip->engine_idx;
134 u8 mask[] = {
135 [LP55XX_ENGINE_1] = LP5562_MODE_ENG1_M,
136 [LP55XX_ENGINE_2] = LP5562_MODE_ENG2_M,
137 [LP55XX_ENGINE_3] = LP5562_MODE_ENG3_M,
138 };
139
140 u8 val[] = {
141 [LP55XX_ENGINE_1] = LP5562_LOAD_ENG1,
142 [LP55XX_ENGINE_2] = LP5562_LOAD_ENG2,
143 [LP55XX_ENGINE_3] = LP5562_LOAD_ENG3,
144 };
145
146 lp55xx_update_bits(chip, LP5562_REG_OP_MODE, mask[idx], val[idx]);
147
148 lp5562_wait_opmode_done();
149}
150
151static void lp5562_stop_engine(struct lp55xx_chip *chip)
152{
153 lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DISABLE);
154 lp5562_wait_opmode_done();
155}
156
157static void lp5562_run_engine(struct lp55xx_chip *chip, bool start)
158{
159 int ret;
160 u8 mode;
161 u8 exec;
162
163 /* stop engine */
164 if (!start) {
165 lp55xx_write(chip, LP5562_REG_ENABLE, LP5562_ENABLE_DEFAULT);
166 lp5562_wait_enable_done();
167 lp5562_stop_engine(chip);
168 lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_PWM);
169 lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DIRECT);
170 lp5562_wait_opmode_done();
171 return;
172 }
173
174 /*
175 * To run the engine,
176 * operation mode and enable register should updated at the same time
177 */
178
179 ret = lp55xx_read(chip, LP5562_REG_OP_MODE, &mode);
180 if (ret)
181 return;
182
183 ret = lp55xx_read(chip, LP5562_REG_ENABLE, &exec);
184 if (ret)
185 return;
186
187 /* change operation mode to RUN only when each engine is loading */
188 if (LP5562_ENG1_IS_LOADING(mode)) {
189 mode = (mode & ~LP5562_MODE_ENG1_M) | LP5562_RUN_ENG1;
190 exec = (exec & ~LP5562_EXEC_ENG1_M) | LP5562_RUN_ENG1;
191 }
192
193 if (LP5562_ENG2_IS_LOADING(mode)) {
194 mode = (mode & ~LP5562_MODE_ENG2_M) | LP5562_RUN_ENG2;
195 exec = (exec & ~LP5562_EXEC_ENG2_M) | LP5562_RUN_ENG2;
196 }
197
198 if (LP5562_ENG3_IS_LOADING(mode)) {
199 mode = (mode & ~LP5562_MODE_ENG3_M) | LP5562_RUN_ENG3;
200 exec = (exec & ~LP5562_EXEC_ENG3_M) | LP5562_RUN_ENG3;
201 }
202
203 lp55xx_write(chip, LP5562_REG_OP_MODE, mode);
204 lp5562_wait_opmode_done();
205
206 lp55xx_update_bits(chip, LP5562_REG_ENABLE, LP5562_EXEC_M, exec);
207 lp5562_wait_enable_done();
208}
209
210static int lp5562_update_firmware(struct lp55xx_chip *chip,
211 const u8 *data, size_t size)
212{
213 enum lp55xx_engine_index idx = chip->engine_idx;
214 u8 pattern[LP5562_PROGRAM_LENGTH] = {0};
215 u8 addr[] = {
216 [LP55XX_ENGINE_1] = LP5562_REG_PROG_MEM_ENG1,
217 [LP55XX_ENGINE_2] = LP5562_REG_PROG_MEM_ENG2,
218 [LP55XX_ENGINE_3] = LP5562_REG_PROG_MEM_ENG3,
219 };
220 unsigned cmd;
221 char c[3];
222 int program_size;
223 int nrchars;
224 int offset = 0;
225 int ret;
226 int i;
227
228 /* clear program memory before updating */
229 for (i = 0; i < LP5562_PROGRAM_LENGTH; i++)
230 lp55xx_write(chip, addr[idx] + i, 0);
231
232 i = 0;
233 while ((offset < size - 1) && (i < LP5562_PROGRAM_LENGTH)) {
234 /* separate sscanfs because length is working only for %s */
235 ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
236 if (ret != 1)
237 goto err;
238
239 ret = sscanf(c, "%2x", &cmd);
240 if (ret != 1)
241 goto err;
242
243 pattern[i] = (u8)cmd;
244 offset += nrchars;
245 i++;
246 }
247
248 /* Each instruction is 16bit long. Check that length is even */
249 if (i % 2)
250 goto err;
251
252 program_size = i;
253 for (i = 0; i < program_size; i++)
254 lp55xx_write(chip, addr[idx] + i, pattern[i]);
255
256 return 0;
257
258err:
259 dev_err(&chip->cl->dev, "wrong pattern format\n");
260 return -EINVAL;
261}
262
263static void lp5562_firmware_loaded(struct lp55xx_chip *chip)
264{
265 const struct firmware *fw = chip->fw;
266
267 if (fw->size > LP5562_PROGRAM_LENGTH) {
268 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
269 fw->size);
270 return;
271 }
272
273 /*
274 * Program momery sequence
275 * 1) set engine mode to "LOAD"
276 * 2) write firmware data into program memory
277 */
278
279 lp5562_load_engine(chip);
280 lp5562_update_firmware(chip, fw->data, fw->size);
281}
282
283static int lp5562_post_init_device(struct lp55xx_chip *chip)
284{
285 int ret;
286 u8 cfg = LP5562_DEFAULT_CFG;
287
288 /* Set all PWMs to direct control mode */
289 ret = lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DIRECT);
290 if (ret)
291 return ret;
292
293 lp5562_wait_opmode_done();
294
295 /* Update configuration for the clock setting */
296 if (!lp55xx_is_extclk_used(chip))
297 cfg |= LP5562_CLK_INT;
298
299 ret = lp55xx_write(chip, LP5562_REG_CONFIG, cfg);
300 if (ret)
301 return ret;
302
303 /* Initialize all channels PWM to zero -> leds off */
304 lp55xx_write(chip, LP5562_REG_R_PWM, 0);
305 lp55xx_write(chip, LP5562_REG_G_PWM, 0);
306 lp55xx_write(chip, LP5562_REG_B_PWM, 0);
307 lp55xx_write(chip, LP5562_REG_W_PWM, 0);
308
309 /* Set LED map as register PWM by default */
310 lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_PWM);
311
312 return 0;
313}
314
315static void lp5562_led_brightness_work(struct work_struct *work)
316{
317 struct lp55xx_led *led = container_of(work, struct lp55xx_led,
318 brightness_work);
319 struct lp55xx_chip *chip = led->chip;
320 u8 addr[] = {
321 LP5562_REG_R_PWM,
322 LP5562_REG_G_PWM,
323 LP5562_REG_B_PWM,
324 LP5562_REG_W_PWM,
325 };
326
327 mutex_lock(&chip->lock);
328 lp55xx_write(chip, addr[led->chan_nr], led->brightness);
329 mutex_unlock(&chip->lock);
330}
331
332static void lp5562_write_program_memory(struct lp55xx_chip *chip,
333 u8 base, const u8 *rgb, int size)
334{
335 int i;
336
337 if (!rgb || size <= 0)
338 return;
339
340 for (i = 0; i < size; i++)
341 lp55xx_write(chip, base + i, *(rgb + i));
342
343 lp55xx_write(chip, base + i, 0);
344 lp55xx_write(chip, base + i + 1, 0);
345}
346
347/* check the size of program count */
348static inline bool _is_pc_overflow(struct lp55xx_predef_pattern *ptn)
349{
350 return (ptn->size_r >= LP5562_PROGRAM_LENGTH ||
351 ptn->size_g >= LP5562_PROGRAM_LENGTH ||
352 ptn->size_b >= LP5562_PROGRAM_LENGTH);
353}
354
355static int lp5562_run_predef_led_pattern(struct lp55xx_chip *chip, int mode)
356{
357 struct lp55xx_predef_pattern *ptn;
358 int i;
359
360 if (mode == LP5562_PATTERN_OFF) {
361 lp5562_run_engine(chip, false);
362 return 0;
363 }
364
365 ptn = chip->pdata->patterns + (mode - 1);
366 if (!ptn || _is_pc_overflow(ptn)) {
367 dev_err(&chip->cl->dev, "invalid pattern data\n");
368 return -EINVAL;
369 }
370
371 lp5562_stop_engine(chip);
372
373 /* Set LED map as RGB */
374 lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_RGB);
375
376 /* Load engines */
377 for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
378 chip->engine_idx = i;
379 lp5562_load_engine(chip);
380 }
381
382 /* Clear program registers */
383 lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG1, 0);
384 lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG1 + 1, 0);
385 lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG2, 0);
386 lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG2 + 1, 0);
387 lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG3, 0);
388 lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG3 + 1, 0);
389
390 /* Program engines */
391 lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG1,
392 ptn->r, ptn->size_r);
393 lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG2,
394 ptn->g, ptn->size_g);
395 lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG3,
396 ptn->b, ptn->size_b);
397
398 /* Run engines */
399 lp5562_run_engine(chip, true);
400
401 return 0;
402}
403
404static ssize_t lp5562_store_pattern(struct device *dev,
405 struct device_attribute *attr,
406 const char *buf, size_t len)
407{
408 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
409 struct lp55xx_chip *chip = led->chip;
410 struct lp55xx_predef_pattern *ptn = chip->pdata->patterns;
411 int num_patterns = chip->pdata->num_patterns;
412 unsigned long mode;
413 int ret;
414
415 ret = kstrtoul(buf, 0, &mode);
416 if (ret)
417 return ret;
418
419 if (mode > num_patterns || !ptn)
420 return -EINVAL;
421
422 mutex_lock(&chip->lock);
423 ret = lp5562_run_predef_led_pattern(chip, mode);
424 mutex_unlock(&chip->lock);
425
426 if (ret)
427 return ret;
428
429 return len;
430}
431
432static ssize_t lp5562_store_engine_mux(struct device *dev,
433 struct device_attribute *attr,
434 const char *buf, size_t len)
435{
436 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
437 struct lp55xx_chip *chip = led->chip;
438 u8 mask;
439 u8 val;
440
441 /* LED map
442 * R ... Engine 1 (fixed)
443 * G ... Engine 2 (fixed)
444 * B ... Engine 3 (fixed)
445 * W ... Engine 1 or 2 or 3
446 */
447
448 if (sysfs_streq(buf, "RGB")) {
449 mask = LP5562_ENG_FOR_RGB_M;
450 val = LP5562_ENG_SEL_RGB;
451 } else if (sysfs_streq(buf, "W")) {
452 enum lp55xx_engine_index idx = chip->engine_idx;
453
454 mask = LP5562_ENG_FOR_W_M;
455 switch (idx) {
456 case LP55XX_ENGINE_1:
457 val = LP5562_ENG1_FOR_W;
458 break;
459 case LP55XX_ENGINE_2:
460 val = LP5562_ENG2_FOR_W;
461 break;
462 case LP55XX_ENGINE_3:
463 val = LP5562_ENG3_FOR_W;
464 break;
465 default:
466 return -EINVAL;
467 }
468
469 } else {
470 dev_err(dev, "choose RGB or W\n");
471 return -EINVAL;
472 }
473
474 mutex_lock(&chip->lock);
475 lp55xx_update_bits(chip, LP5562_REG_ENG_SEL, mask, val);
476 mutex_unlock(&chip->lock);
477
478 return len;
479}
480
481static LP55XX_DEV_ATTR_WO(led_pattern, lp5562_store_pattern);
482static LP55XX_DEV_ATTR_WO(engine_mux, lp5562_store_engine_mux);
483
484static struct attribute *lp5562_attributes[] = {
485 &dev_attr_led_pattern.attr,
486 &dev_attr_engine_mux.attr,
487 NULL,
488};
489
490static const struct attribute_group lp5562_group = {
491 .attrs = lp5562_attributes,
492};
493
494/* Chip specific configurations */
495static struct lp55xx_device_config lp5562_cfg = {
496 .max_channel = LP5562_MAX_LEDS,
497 .reset = {
498 .addr = LP5562_REG_RESET,
499 .val = LP5562_RESET,
500 },
501 .enable = {
502 .addr = LP5562_REG_ENABLE,
503 .val = LP5562_ENABLE_DEFAULT,
504 },
505 .post_init_device = lp5562_post_init_device,
506 .set_led_current = lp5562_set_led_current,
507 .brightness_work_fn = lp5562_led_brightness_work,
508 .run_engine = lp5562_run_engine,
509 .firmware_cb = lp5562_firmware_loaded,
510 .dev_attr_group = &lp5562_group,
511};
512
513static int lp5562_probe(struct i2c_client *client,
514 const struct i2c_device_id *id)
515{
516 int ret;
517 struct lp55xx_chip *chip;
518 struct lp55xx_led *led;
519 struct lp55xx_platform_data *pdata;
520 struct device_node *np = client->dev.of_node;
521
522 if (!dev_get_platdata(&client->dev)) {
523 if (np) {
524 ret = lp55xx_of_populate_pdata(&client->dev, np);
525 if (ret < 0)
526 return ret;
527 } else {
528 dev_err(&client->dev, "no platform data\n");
529 return -EINVAL;
530 }
531 }
532 pdata = dev_get_platdata(&client->dev);
533
534 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
535 if (!chip)
536 return -ENOMEM;
537
538 led = devm_kzalloc(&client->dev,
539 sizeof(*led) * pdata->num_channels, GFP_KERNEL);
540 if (!led)
541 return -ENOMEM;
542
543 chip->cl = client;
544 chip->pdata = pdata;
545 chip->cfg = &lp5562_cfg;
546
547 mutex_init(&chip->lock);
548
549 i2c_set_clientdata(client, led);
550
551 ret = lp55xx_init_device(chip);
552 if (ret)
553 goto err_init;
554
555 ret = lp55xx_register_leds(led, chip);
556 if (ret)
557 goto err_register_leds;
558
559 ret = lp55xx_register_sysfs(chip);
560 if (ret) {
561 dev_err(&client->dev, "registering sysfs failed\n");
562 goto err_register_sysfs;
563 }
564
565 return 0;
566
567err_register_sysfs:
568 lp55xx_unregister_leds(led, chip);
569err_register_leds:
570 lp55xx_deinit_device(chip);
571err_init:
572 return ret;
573}
574
575static int lp5562_remove(struct i2c_client *client)
576{
577 struct lp55xx_led *led = i2c_get_clientdata(client);
578 struct lp55xx_chip *chip = led->chip;
579
580 lp5562_stop_engine(chip);
581
582 lp55xx_unregister_sysfs(chip);
583 lp55xx_unregister_leds(led, chip);
584 lp55xx_deinit_device(chip);
585
586 return 0;
587}
588
589static const struct i2c_device_id lp5562_id[] = {
590 { "lp5562", 0 },
591 { }
592};
593MODULE_DEVICE_TABLE(i2c, lp5562_id);
594
595#ifdef CONFIG_OF
596static const struct of_device_id of_lp5562_leds_match[] = {
597 { .compatible = "ti,lp5562", },
598 {},
599};
600
601MODULE_DEVICE_TABLE(of, of_lp5562_leds_match);
602#endif
603
604static struct i2c_driver lp5562_driver = {
605 .driver = {
606 .name = "lp5562",
607 .of_match_table = of_match_ptr(of_lp5562_leds_match),
608 },
609 .probe = lp5562_probe,
610 .remove = lp5562_remove,
611 .id_table = lp5562_id,
612};
613
614module_i2c_driver(lp5562_driver);
615
616MODULE_DESCRIPTION("Texas Instruments LP5562 LED Driver");
617MODULE_AUTHOR("Milo Kim");
618MODULE_LICENSE("GPL");