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Linux 3.4.102
[linux/fpc-iii.git] / drivers / leds / leds-lp5521.c
blob23815624f35ef59ea11d6cfe167e173257c548c2
1 /*
2 * LP5521 LED chip driver.
3 *
4 * Copyright (C) 2010 Nokia Corporation
5 *
6 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * version 2 as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20 * 02110-1301 USA
21 */
22
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/i2c.h>
26 #include <linux/mutex.h>
27 #include <linux/gpio.h>
28 #include <linux/interrupt.h>
29 #include <linux/delay.h>
30 #include <linux/ctype.h>
31 #include <linux/spinlock.h>
32 #include <linux/wait.h>
33 #include <linux/leds.h>
34 #include <linux/leds-lp5521.h>
35 #include <linux/workqueue.h>
36 #include <linux/slab.h>
37
38 #define LP5521_PROGRAM_LENGTH 32 /* in bytes */
39
40 #define LP5521_MAX_LEDS 3 /* Maximum number of LEDs */
41 #define LP5521_MAX_ENGINES 3 /* Maximum number of engines */
42
43 #define LP5521_ENG_MASK_BASE 0x30 /* 00110000 */
44 #define LP5521_ENG_STATUS_MASK 0x07 /* 00000111 */
45
46 #define LP5521_CMD_LOAD 0x15 /* 00010101 */
47 #define LP5521_CMD_RUN 0x2a /* 00101010 */
48 #define LP5521_CMD_DIRECT 0x3f /* 00111111 */
49 #define LP5521_CMD_DISABLED 0x00 /* 00000000 */
50
51 /* Registers */
52 #define LP5521_REG_ENABLE 0x00
53 #define LP5521_REG_OP_MODE 0x01
54 #define LP5521_REG_R_PWM 0x02
55 #define LP5521_REG_G_PWM 0x03
56 #define LP5521_REG_B_PWM 0x04
57 #define LP5521_REG_R_CURRENT 0x05
58 #define LP5521_REG_G_CURRENT 0x06
59 #define LP5521_REG_B_CURRENT 0x07
60 #define LP5521_REG_CONFIG 0x08
61 #define LP5521_REG_R_CHANNEL_PC 0x09
62 #define LP5521_REG_G_CHANNEL_PC 0x0A
63 #define LP5521_REG_B_CHANNEL_PC 0x0B
64 #define LP5521_REG_STATUS 0x0C
65 #define LP5521_REG_RESET 0x0D
66 #define LP5521_REG_GPO 0x0E
67 #define LP5521_REG_R_PROG_MEM 0x10
68 #define LP5521_REG_G_PROG_MEM 0x30
69 #define LP5521_REG_B_PROG_MEM 0x50
70
71 #define LP5521_PROG_MEM_BASE LP5521_REG_R_PROG_MEM
72 #define LP5521_PROG_MEM_SIZE 0x20
73
74 /* Base register to set LED current */
75 #define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT
76
77 /* Base register to set the brightness */
78 #define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM
79
80 /* Bits in ENABLE register */
81 #define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */
82 #define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */
83 #define LP5521_EXEC_RUN 0x2A
84 #define LP5521_ENABLE_DEFAULT \
85 (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
86 #define LP5521_ENABLE_RUN_PROGRAM \
87 (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)
88
89 /* Status */
90 #define LP5521_EXT_CLK_USED 0x08
91
92 /* default R channel current register value */
93 #define LP5521_REG_R_CURR_DEFAULT 0xAF
94
95 /* Pattern Mode */
96 #define PATTERN_OFF 0
97
98 struct lp5521_engine {
99 int id;
100 u8 mode;
101 u8 prog_page;
102 u8 engine_mask;
103 };
104
105 struct lp5521_led {
106 int id;
107 u8 chan_nr;
108 u8 led_current;
109 u8 max_current;
110 struct led_classdev cdev;
111 struct work_struct brightness_work;
112 u8 brightness;
113 };
114
115 struct lp5521_chip {
116 struct lp5521_platform_data *pdata;
117 struct mutex lock; /* Serialize control */
118 struct i2c_client *client;
119 struct lp5521_engine engines[LP5521_MAX_ENGINES];
120 struct lp5521_led leds[LP5521_MAX_LEDS];
121 u8 num_channels;
122 u8 num_leds;
123 };
124
125 static inline struct lp5521_led *cdev_to_led(struct led_classdev *cdev)
126 {
127 return container_of(cdev, struct lp5521_led, cdev);
128 }
129
130 static inline struct lp5521_chip *engine_to_lp5521(struct lp5521_engine *engine)
131 {
132 return container_of(engine, struct lp5521_chip,
133 engines[engine->id - 1]);
134 }
135
136 static inline struct lp5521_chip *led_to_lp5521(struct lp5521_led *led)
137 {
138 return container_of(led, struct lp5521_chip,
139 leds[led->id]);
140 }
141
142 static void lp5521_led_brightness_work(struct work_struct *work);
143
144 static inline int lp5521_write(struct i2c_client *client, u8 reg, u8 value)
145 {
146 return i2c_smbus_write_byte_data(client, reg, value);
147 }
148
149 static int lp5521_read(struct i2c_client *client, u8 reg, u8 *buf)
150 {
151 s32 ret;
152
153 ret = i2c_smbus_read_byte_data(client, reg);
154 if (ret < 0)
155 return -EIO;
156
157 *buf = ret;
158 return 0;
159 }
160
161 static int lp5521_set_engine_mode(struct lp5521_engine *engine, u8 mode)
162 {
163 struct lp5521_chip *chip = engine_to_lp5521(engine);
164 struct i2c_client *client = chip->client;
165 int ret;
166 u8 engine_state;
167
168 /* Only transition between RUN and DIRECT mode are handled here */
169 if (mode == LP5521_CMD_LOAD)
170 return 0;
171
172 if (mode == LP5521_CMD_DISABLED)
173 mode = LP5521_CMD_DIRECT;
174
175 ret = lp5521_read(client, LP5521_REG_OP_MODE, &engine_state);
176 if (ret < 0)
177 return ret;
178
179 /* set mode only for this engine */
180 engine_state &= ~(engine->engine_mask);
181 mode &= engine->engine_mask;
182 engine_state |= mode;
183 return lp5521_write(client, LP5521_REG_OP_MODE, engine_state);
184 }
185
186 static int lp5521_load_program(struct lp5521_engine *eng, const u8 *pattern)
187 {
188 struct lp5521_chip *chip = engine_to_lp5521(eng);
189 struct i2c_client *client = chip->client;
190 int ret;
191 int addr;
192 u8 mode;
193
194 /* move current engine to direct mode and remember the state */
195 ret = lp5521_set_engine_mode(eng, LP5521_CMD_DIRECT);
196 if (ret)
197 return ret;
198
199 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
200 usleep_range(1000, 2000);
201 ret = lp5521_read(client, LP5521_REG_OP_MODE, &mode);
202 if (ret)
203 return ret;
204
205 /* For loading, all the engines to load mode */
206 lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
207 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
208 usleep_range(1000, 2000);
209 lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
210 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
211 usleep_range(1000, 2000);
212
213 addr = LP5521_PROG_MEM_BASE + eng->prog_page * LP5521_PROG_MEM_SIZE;
214 i2c_smbus_write_i2c_block_data(client,
215 addr,
216 LP5521_PROG_MEM_SIZE,
217 pattern);
218
219 return lp5521_write(client, LP5521_REG_OP_MODE, mode);
220 }
221
222 static int lp5521_set_led_current(struct lp5521_chip *chip, int led, u8 curr)
223 {
224 return lp5521_write(chip->client,
225 LP5521_REG_LED_CURRENT_BASE + chip->leds[led].chan_nr,
226 curr);
227 }
228
229 static void lp5521_init_engine(struct lp5521_chip *chip)
230 {
231 int i;
232 for (i = 0; i < ARRAY_SIZE(chip->engines); i++) {
233 chip->engines[i].id = i + 1;
234 chip->engines[i].engine_mask = LP5521_ENG_MASK_BASE >> (i * 2);
235 chip->engines[i].prog_page = i;
236 }
237 }
238
239 static int lp5521_configure(struct i2c_client *client)
240 {
241 struct lp5521_chip *chip = i2c_get_clientdata(client);
242 int ret;
243 u8 cfg;
244
245 lp5521_init_engine(chip);
246
247 /* Set all PWMs to direct control mode */
248 ret = lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
249
250 cfg = chip->pdata->update_config ?
251 : (LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO | LP5521_R_TO_BATT);
252 ret |= lp5521_write(client, LP5521_REG_CONFIG, cfg);
253
254 /* Initialize all channels PWM to zero -> leds off */
255 ret |= lp5521_write(client, LP5521_REG_R_PWM, 0);
256 ret |= lp5521_write(client, LP5521_REG_G_PWM, 0);
257 ret |= lp5521_write(client, LP5521_REG_B_PWM, 0);
258
259 /* Set engines are set to run state when OP_MODE enables engines */
260 ret |= lp5521_write(client, LP5521_REG_ENABLE,
261 LP5521_ENABLE_RUN_PROGRAM);
262 /* enable takes 500us. 1 - 2 ms leaves some margin */
263 usleep_range(1000, 2000);
264
265 return ret;
266 }
267
268 static int lp5521_run_selftest(struct lp5521_chip *chip, char *buf)
269 {
270 int ret;
271 u8 status;
272
273 ret = lp5521_read(chip->client, LP5521_REG_STATUS, &status);
274 if (ret < 0)
275 return ret;
276
277 /* Check that ext clock is really in use if requested */
278 if (chip->pdata && chip->pdata->clock_mode == LP5521_CLOCK_EXT)
279 if ((status & LP5521_EXT_CLK_USED) == 0)
280 return -EIO;
281 return 0;
282 }
283
284 static void lp5521_set_brightness(struct led_classdev *cdev,
285 enum led_brightness brightness)
286 {
287 struct lp5521_led *led = cdev_to_led(cdev);
288 led->brightness = (u8)brightness;
289 schedule_work(&led->brightness_work);
290 }
291
292 static void lp5521_led_brightness_work(struct work_struct *work)
293 {
294 struct lp5521_led *led = container_of(work,
295 struct lp5521_led,
296 brightness_work);
297 struct lp5521_chip *chip = led_to_lp5521(led);
298 struct i2c_client *client = chip->client;
299
300 mutex_lock(&chip->lock);
301 lp5521_write(client, LP5521_REG_LED_PWM_BASE + led->chan_nr,
302 led->brightness);
303 mutex_unlock(&chip->lock);
304 }
305
306 /* Detect the chip by setting its ENABLE register and reading it back. */
307 static int lp5521_detect(struct i2c_client *client)
308 {
309 int ret;
310 u8 buf;
311
312 ret = lp5521_write(client, LP5521_REG_ENABLE, LP5521_ENABLE_DEFAULT);
313 if (ret)
314 return ret;
315 /* enable takes 500us. 1 - 2 ms leaves some margin */
316 usleep_range(1000, 2000);
317 ret = lp5521_read(client, LP5521_REG_ENABLE, &buf);
318 if (ret)
319 return ret;
320 if (buf != LP5521_ENABLE_DEFAULT)
321 return -ENODEV;
322
323 return 0;
324 }
325
326 /* Set engine mode and create appropriate sysfs attributes, if required. */
327 static int lp5521_set_mode(struct lp5521_engine *engine, u8 mode)
328 {
329 int ret = 0;
330
331 /* if in that mode already do nothing, except for run */
332 if (mode == engine->mode && mode != LP5521_CMD_RUN)
333 return 0;
334
335 if (mode == LP5521_CMD_RUN) {
336 ret = lp5521_set_engine_mode(engine, LP5521_CMD_RUN);
337 } else if (mode == LP5521_CMD_LOAD) {
338 lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
339 lp5521_set_engine_mode(engine, LP5521_CMD_LOAD);
340 } else if (mode == LP5521_CMD_DISABLED) {
341 lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
342 }
343
344 engine->mode = mode;
345
346 return ret;
347 }
348
349 static int lp5521_do_store_load(struct lp5521_engine *engine,
350 const char *buf, size_t len)
351 {
352 struct lp5521_chip *chip = engine_to_lp5521(engine);
353 struct i2c_client *client = chip->client;
354 int ret, nrchars, offset = 0, i = 0;
355 char c[3];
356 unsigned cmd;
357 u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
358
359 while ((offset < len - 1) && (i < LP5521_PROGRAM_LENGTH)) {
360 /* separate sscanfs because length is working only for %s */
361 ret = sscanf(buf + offset, "%2s%n ", c, &nrchars);
362 if (ret != 2)
363 goto fail;
364 ret = sscanf(c, "%2x", &cmd);
365 if (ret != 1)
366 goto fail;
367 pattern[i] = (u8)cmd;
368
369 offset += nrchars;
370 i++;
371 }
372
373 /* Each instruction is 16bit long. Check that length is even */
374 if (i % 2)
375 goto fail;
376
377 mutex_lock(&chip->lock);
378 if (engine->mode == LP5521_CMD_LOAD)
379 ret = lp5521_load_program(engine, pattern);
380 else
381 ret = -EINVAL;
382 mutex_unlock(&chip->lock);
383
384 if (ret) {
385 dev_err(&client->dev, "failed loading pattern\n");
386 return ret;
387 }
388
389 return len;
390 fail:
391 dev_err(&client->dev, "wrong pattern format\n");
392 return -EINVAL;
393 }
394
395 static ssize_t store_engine_load(struct device *dev,
396 struct device_attribute *attr,
397 const char *buf, size_t len, int nr)
398 {
399 struct i2c_client *client = to_i2c_client(dev);
400 struct lp5521_chip *chip = i2c_get_clientdata(client);
401 return lp5521_do_store_load(&chip->engines[nr - 1], buf, len);
402 }
403
404 #define store_load(nr) \
405 static ssize_t store_engine##nr##_load(struct device *dev, \
406 struct device_attribute *attr, \
407 const char *buf, size_t len) \
408 { \
409 return store_engine_load(dev, attr, buf, len, nr); \
410 }
411 store_load(1)
412 store_load(2)
413 store_load(3)
414
415 static ssize_t show_engine_mode(struct device *dev,
416 struct device_attribute *attr,
417 char *buf, int nr)
418 {
419 struct i2c_client *client = to_i2c_client(dev);
420 struct lp5521_chip *chip = i2c_get_clientdata(client);
421 switch (chip->engines[nr - 1].mode) {
422 case LP5521_CMD_RUN:
423 return sprintf(buf, "run\n");
424 case LP5521_CMD_LOAD:
425 return sprintf(buf, "load\n");
426 case LP5521_CMD_DISABLED:
427 return sprintf(buf, "disabled\n");
428 default:
429 return sprintf(buf, "disabled\n");
430 }
431 }
432
433 #define show_mode(nr) \
434 static ssize_t show_engine##nr##_mode(struct device *dev, \
435 struct device_attribute *attr, \
436 char *buf) \
437 { \
438 return show_engine_mode(dev, attr, buf, nr); \
439 }
440 show_mode(1)
441 show_mode(2)
442 show_mode(3)
443
444 static ssize_t store_engine_mode(struct device *dev,
445 struct device_attribute *attr,
446 const char *buf, size_t len, int nr)
447 {
448 struct i2c_client *client = to_i2c_client(dev);
449 struct lp5521_chip *chip = i2c_get_clientdata(client);
450 struct lp5521_engine *engine = &chip->engines[nr - 1];
451 mutex_lock(&chip->lock);
452
453 if (!strncmp(buf, "run", 3))
454 lp5521_set_mode(engine, LP5521_CMD_RUN);
455 else if (!strncmp(buf, "load", 4))
456 lp5521_set_mode(engine, LP5521_CMD_LOAD);
457 else if (!strncmp(buf, "disabled", 8))
458 lp5521_set_mode(engine, LP5521_CMD_DISABLED);
459
460 mutex_unlock(&chip->lock);
461 return len;
462 }
463
464 #define store_mode(nr) \
465 static ssize_t store_engine##nr##_mode(struct device *dev, \
466 struct device_attribute *attr, \
467 const char *buf, size_t len) \
468 { \
469 return store_engine_mode(dev, attr, buf, len, nr); \
470 }
471 store_mode(1)
472 store_mode(2)
473 store_mode(3)
474
475 static ssize_t show_max_current(struct device *dev,
476 struct device_attribute *attr,
477 char *buf)
478 {
479 struct led_classdev *led_cdev = dev_get_drvdata(dev);
480 struct lp5521_led *led = cdev_to_led(led_cdev);
481
482 return sprintf(buf, "%d\n", led->max_current);
483 }
484
485 static ssize_t show_current(struct device *dev,
486 struct device_attribute *attr,
487 char *buf)
488 {
489 struct led_classdev *led_cdev = dev_get_drvdata(dev);
490 struct lp5521_led *led = cdev_to_led(led_cdev);
491
492 return sprintf(buf, "%d\n", led->led_current);
493 }
494
495 static ssize_t store_current(struct device *dev,
496 struct device_attribute *attr,
497 const char *buf, size_t len)
498 {
499 struct led_classdev *led_cdev = dev_get_drvdata(dev);
500 struct lp5521_led *led = cdev_to_led(led_cdev);
501 struct lp5521_chip *chip = led_to_lp5521(led);
502 ssize_t ret;
503 unsigned long curr;
504
505 if (kstrtoul(buf, 0, &curr))
506 return -EINVAL;
507
508 if (curr > led->max_current)
509 return -EINVAL;
510
511 mutex_lock(&chip->lock);
512 ret = lp5521_set_led_current(chip, led->id, curr);
513 mutex_unlock(&chip->lock);
514
515 if (ret < 0)
516 return ret;
517
518 led->led_current = (u8)curr;
519
520 return len;
521 }
522
523 static ssize_t lp5521_selftest(struct device *dev,
524 struct device_attribute *attr,
525 char *buf)
526 {
527 struct i2c_client *client = to_i2c_client(dev);
528 struct lp5521_chip *chip = i2c_get_clientdata(client);
529 int ret;
530
531 mutex_lock(&chip->lock);
532 ret = lp5521_run_selftest(chip, buf);
533 mutex_unlock(&chip->lock);
534 return sprintf(buf, "%s\n", ret ? "FAIL" : "OK");
535 }
536
537 static void lp5521_clear_program_memory(struct i2c_client *cl)
538 {
539 int i;
540 u8 rgb_mem[] = {
541 LP5521_REG_R_PROG_MEM,
542 LP5521_REG_G_PROG_MEM,
543 LP5521_REG_B_PROG_MEM,
544 };
545
546 for (i = 0; i < ARRAY_SIZE(rgb_mem); i++) {
547 lp5521_write(cl, rgb_mem[i], 0);
548 lp5521_write(cl, rgb_mem[i] + 1, 0);
549 }
550 }
551
552 static void lp5521_write_program_memory(struct i2c_client *cl,
553 u8 base, u8 *rgb, int size)
554 {
555 int i;
556
557 if (!rgb || size <= 0)
558 return;
559
560 for (i = 0; i < size; i++)
561 lp5521_write(cl, base + i, *(rgb + i));
562
563 lp5521_write(cl, base + i, 0);
564 lp5521_write(cl, base + i + 1, 0);
565 }
566
567 static inline struct lp5521_led_pattern *lp5521_get_pattern
568 (struct lp5521_chip *chip, u8 offset)
569 {
570 struct lp5521_led_pattern *ptn;
571 ptn = chip->pdata->patterns + (offset - 1);
572 return ptn;
573 }
574
575 static void lp5521_run_led_pattern(int mode, struct lp5521_chip *chip)
576 {
577 struct lp5521_led_pattern *ptn;
578 struct i2c_client *cl = chip->client;
579 int num_patterns = chip->pdata->num_patterns;
580
581 if (mode > num_patterns || !(chip->pdata->patterns))
582 return;
583
584 if (mode == PATTERN_OFF) {
585 lp5521_write(cl, LP5521_REG_ENABLE, LP5521_ENABLE_DEFAULT);
586 usleep_range(1000, 2000);
587 lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
588 } else {
589 ptn = lp5521_get_pattern(chip, mode);
590 if (!ptn)
591 return;
592
593 lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
594 usleep_range(1000, 2000);
595
596 lp5521_clear_program_memory(cl);
597
598 lp5521_write_program_memory(cl, LP5521_REG_R_PROG_MEM,
599 ptn->r, ptn->size_r);
600 lp5521_write_program_memory(cl, LP5521_REG_G_PROG_MEM,
601 ptn->g, ptn->size_g);
602 lp5521_write_program_memory(cl, LP5521_REG_B_PROG_MEM,
603 ptn->b, ptn->size_b);
604
605 lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_RUN);
606 usleep_range(1000, 2000);
607 lp5521_write(cl, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
608 }
609 }
610
611 static ssize_t store_led_pattern(struct device *dev,
612 struct device_attribute *attr,
613 const char *buf, size_t len)
614 {
615 struct lp5521_chip *chip = i2c_get_clientdata(to_i2c_client(dev));
616 unsigned long val;
617 int ret;
618
619 ret = strict_strtoul(buf, 16, &val);
620 if (ret)
621 return ret;
622
623 lp5521_run_led_pattern(val, chip);
624
625 return len;
626 }
627
628 /* led class device attributes */
629 static DEVICE_ATTR(led_current, S_IRUGO | S_IWUSR, show_current, store_current);
630 static DEVICE_ATTR(max_current, S_IRUGO , show_max_current, NULL);
631
632 static struct attribute *lp5521_led_attributes[] = {
633 &dev_attr_led_current.attr,
634 &dev_attr_max_current.attr,
635 NULL,
636 };
637
638 static struct attribute_group lp5521_led_attribute_group = {
639 .attrs = lp5521_led_attributes
640 };
641
642 /* device attributes */
643 static DEVICE_ATTR(engine1_mode, S_IRUGO | S_IWUSR,
644 show_engine1_mode, store_engine1_mode);
645 static DEVICE_ATTR(engine2_mode, S_IRUGO | S_IWUSR,
646 show_engine2_mode, store_engine2_mode);
647 static DEVICE_ATTR(engine3_mode, S_IRUGO | S_IWUSR,
648 show_engine3_mode, store_engine3_mode);
649 static DEVICE_ATTR(engine1_load, S_IWUSR, NULL, store_engine1_load);
650 static DEVICE_ATTR(engine2_load, S_IWUSR, NULL, store_engine2_load);
651 static DEVICE_ATTR(engine3_load, S_IWUSR, NULL, store_engine3_load);
652 static DEVICE_ATTR(selftest, S_IRUGO, lp5521_selftest, NULL);
653 static DEVICE_ATTR(led_pattern, S_IWUSR, NULL, store_led_pattern);
654
655 static struct attribute *lp5521_attributes[] = {
656 &dev_attr_engine1_mode.attr,
657 &dev_attr_engine2_mode.attr,
658 &dev_attr_engine3_mode.attr,
659 &dev_attr_selftest.attr,
660 &dev_attr_engine1_load.attr,
661 &dev_attr_engine2_load.attr,
662 &dev_attr_engine3_load.attr,
663 &dev_attr_led_pattern.attr,
664 NULL
665 };
666
667 static const struct attribute_group lp5521_group = {
668 .attrs = lp5521_attributes,
669 };
670
671 static int lp5521_register_sysfs(struct i2c_client *client)
672 {
673 struct device *dev = &client->dev;
674 return sysfs_create_group(&dev->kobj, &lp5521_group);
675 }
676
677 static void lp5521_unregister_sysfs(struct i2c_client *client)
678 {
679 struct lp5521_chip *chip = i2c_get_clientdata(client);
680 struct device *dev = &client->dev;
681 int i;
682
683 sysfs_remove_group(&dev->kobj, &lp5521_group);
684
685 for (i = 0; i < chip->num_leds; i++)
686 sysfs_remove_group(&chip->leds[i].cdev.dev->kobj,
687 &lp5521_led_attribute_group);
688 }
689
690 static int __devinit lp5521_init_led(struct lp5521_led *led,
691 struct i2c_client *client,
692 int chan, struct lp5521_platform_data *pdata)
693 {
694 struct device *dev = &client->dev;
695 char name[32];
696 int res;
697
698 if (chan >= LP5521_MAX_LEDS)
699 return -EINVAL;
700
701 if (pdata->led_config[chan].led_current == 0)
702 return 0;
703
704 led->led_current = pdata->led_config[chan].led_current;
705 led->max_current = pdata->led_config[chan].max_current;
706 led->chan_nr = pdata->led_config[chan].chan_nr;
707
708 if (led->chan_nr >= LP5521_MAX_LEDS) {
709 dev_err(dev, "Use channel numbers between 0 and %d\n",
710 LP5521_MAX_LEDS - 1);
711 return -EINVAL;
712 }
713
714 led->cdev.brightness_set = lp5521_set_brightness;
715 if (pdata->led_config[chan].name) {
716 led->cdev.name = pdata->led_config[chan].name;
717 } else {
718 snprintf(name, sizeof(name), "%s:channel%d",
719 pdata->label ?: client->name, chan);
720 led->cdev.name = name;
721 }
722
723 res = led_classdev_register(dev, &led->cdev);
724 if (res < 0) {
725 dev_err(dev, "couldn't register led on channel %d\n", chan);
726 return res;
727 }
728
729 res = sysfs_create_group(&led->cdev.dev->kobj,
730 &lp5521_led_attribute_group);
731 if (res < 0) {
732 dev_err(dev, "couldn't register current attribute\n");
733 led_classdev_unregister(&led->cdev);
734 return res;
735 }
736 return 0;
737 }
738
739 static int __devinit lp5521_probe(struct i2c_client *client,
740 const struct i2c_device_id *id)
741 {
742 struct lp5521_chip *chip;
743 struct lp5521_platform_data *pdata;
744 int ret, i, led;
745 u8 buf;
746
747 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
748 if (!chip)
749 return -ENOMEM;
750
751 i2c_set_clientdata(client, chip);
752 chip->client = client;
753
754 pdata = client->dev.platform_data;
755
756 if (!pdata) {
757 dev_err(&client->dev, "no platform data\n");
758 ret = -EINVAL;
759 goto fail1;
760 }
761
762 mutex_init(&chip->lock);
763
764 chip->pdata = pdata;
765
766 if (pdata->setup_resources) {
767 ret = pdata->setup_resources();
768 if (ret < 0)
769 goto fail1;
770 }
771
772 if (pdata->enable) {
773 pdata->enable(0);
774 usleep_range(1000, 2000); /* Keep enable down at least 1ms */
775 pdata->enable(1);
776 usleep_range(1000, 2000); /* 500us abs min. */
777 }
778
779 lp5521_write(client, LP5521_REG_RESET, 0xff);
780 usleep_range(10000, 20000); /*
781 * Exact value is not available. 10 - 20ms
782 * appears to be enough for reset.
783 */
784
785 /*
786 * Make sure that the chip is reset by reading back the r channel
787 * current reg. This is dummy read is required on some platforms -
788 * otherwise further access to the R G B channels in the
789 * LP5521_REG_ENABLE register will not have any effect - strange!
790 */
791 ret = lp5521_read(client, LP5521_REG_R_CURRENT, &buf);
792 if (ret || buf != LP5521_REG_R_CURR_DEFAULT) {
793 dev_err(&client->dev, "error in resetting chip\n");
794 goto fail2;
795 }
796 usleep_range(10000, 20000);
797
798 ret = lp5521_detect(client);
799
800 if (ret) {
801 dev_err(&client->dev, "Chip not found\n");
802 goto fail2;
803 }
804
805 dev_info(&client->dev, "%s programmable led chip found\n", id->name);
806
807 ret = lp5521_configure(client);
808 if (ret < 0) {
809 dev_err(&client->dev, "error configuring chip\n");
810 goto fail2;
811 }
812
813 /* Initialize leds */
814 chip->num_channels = pdata->num_channels;
815 chip->num_leds = 0;
816 led = 0;
817 for (i = 0; i < pdata->num_channels; i++) {
818 /* Do not initialize channels that are not connected */
819 if (pdata->led_config[i].led_current == 0)
820 continue;
821
822 ret = lp5521_init_led(&chip->leds[led], client, i, pdata);
823 if (ret) {
824 dev_err(&client->dev, "error initializing leds\n");
825 goto fail3;
826 }
827 chip->num_leds++;
828
829 chip->leds[led].id = led;
830 /* Set initial LED current */
831 lp5521_set_led_current(chip, led,
832 chip->leds[led].led_current);
833
834 INIT_WORK(&(chip->leds[led].brightness_work),
835 lp5521_led_brightness_work);
836
837 led++;
838 }
839
840 ret = lp5521_register_sysfs(client);
841 if (ret) {
842 dev_err(&client->dev, "registering sysfs failed\n");
843 goto fail3;
844 }
845 return ret;
846 fail3:
847 for (i = 0; i < chip->num_leds; i++) {
848 led_classdev_unregister(&chip->leds[i].cdev);
849 cancel_work_sync(&chip->leds[i].brightness_work);
850 }
851 fail2:
852 if (pdata->enable)
853 pdata->enable(0);
854 if (pdata->release_resources)
855 pdata->release_resources();
856 fail1:
857 kfree(chip);
858 return ret;
859 }
860
861 static int __devexit lp5521_remove(struct i2c_client *client)
862 {
863 struct lp5521_chip *chip = i2c_get_clientdata(client);
864 int i;
865
866 lp5521_run_led_pattern(PATTERN_OFF, chip);
867 lp5521_unregister_sysfs(client);
868
869 for (i = 0; i < chip->num_leds; i++) {
870 led_classdev_unregister(&chip->leds[i].cdev);
871 cancel_work_sync(&chip->leds[i].brightness_work);
872 }
873
874 if (chip->pdata->enable)
875 chip->pdata->enable(0);
876 if (chip->pdata->release_resources)
877 chip->pdata->release_resources();
878 kfree(chip);
879 return 0;
880 }
881
882 static const struct i2c_device_id lp5521_id[] = {
883 { "lp5521", 0 }, /* Three channel chip */
884 { }
885 };
886 MODULE_DEVICE_TABLE(i2c, lp5521_id);
887
888 static struct i2c_driver lp5521_driver = {
889 .driver = {
890 .name = "lp5521",
891 },
892 .probe = lp5521_probe,
893 .remove = __devexit_p(lp5521_remove),
894 .id_table = lp5521_id,
895 };
896
897 module_i2c_driver(lp5521_driver);
898
899 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
900 MODULE_DESCRIPTION("LP5521 LED engine");
901 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support