?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Merge remote-tracking branch 'logfs/master'
[linux-2.6/next.git] / drivers / leds / leds-lp5521.c
blob9fc122c81f06cfc350ff224d432c1ed0dddeadd8
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
85 /* Bits in CONFIG register */
86 #define LP5521_PWM_HF 0x40 /* PWM: 0 = 256Hz, 1 = 558Hz */
87 #define LP5521_PWRSAVE_EN 0x20 /* 1 = Power save mode */
88 #define LP5521_CP_MODE_OFF 0 /* Charge pump (CP) off */
89 #define LP5521_CP_MODE_BYPASS 8 /* CP forced to bypass mode */
90 #define LP5521_CP_MODE_1X5 0x10 /* CP forced to 1.5x mode */
91 #define LP5521_CP_MODE_AUTO 0x18 /* Automatic mode selection */
92 #define LP5521_R_TO_BATT 4 /* R out: 0 = CP, 1 = Vbat */
93 #define LP5521_CLK_SRC_EXT 0 /* Ext-clk source (CLK_32K) */
94 #define LP5521_CLK_INT 1 /* Internal clock */
95 #define LP5521_CLK_AUTO 2 /* Automatic clock selection */
96
97 /* Status */
98 #define LP5521_EXT_CLK_USED 0x08
99
100 struct lp5521_engine {
101 int id;
102 u8 mode;
103 u8 prog_page;
104 u8 engine_mask;
105 };
106
107 struct lp5521_led {
108 int id;
109 u8 chan_nr;
110 u8 led_current;
111 u8 max_current;
112 struct led_classdev cdev;
113 struct work_struct brightness_work;
114 u8 brightness;
115 };
116
117 struct lp5521_chip {
118 struct lp5521_platform_data *pdata;
119 struct mutex lock; /* Serialize control */
120 struct i2c_client *client;
121 struct lp5521_engine engines[LP5521_MAX_ENGINES];
122 struct lp5521_led leds[LP5521_MAX_LEDS];
123 u8 num_channels;
124 u8 num_leds;
125 };
126
127 static inline struct lp5521_led *cdev_to_led(struct led_classdev *cdev)
128 {
129 return container_of(cdev, struct lp5521_led, cdev);
130 }
131
132 static inline struct lp5521_chip *engine_to_lp5521(struct lp5521_engine *engine)
133 {
134 return container_of(engine, struct lp5521_chip,
135 engines[engine->id - 1]);
136 }
137
138 static inline struct lp5521_chip *led_to_lp5521(struct lp5521_led *led)
139 {
140 return container_of(led, struct lp5521_chip,
141 leds[led->id]);
142 }
143
144 static void lp5521_led_brightness_work(struct work_struct *work);
145
146 static inline int lp5521_write(struct i2c_client *client, u8 reg, u8 value)
147 {
148 return i2c_smbus_write_byte_data(client, reg, value);
149 }
150
151 static int lp5521_read(struct i2c_client *client, u8 reg, u8 *buf)
152 {
153 s32 ret;
154
155 ret = i2c_smbus_read_byte_data(client, reg);
156 if (ret < 0)
157 return -EIO;
158
159 *buf = ret;
160 return 0;
161 }
162
163 static int lp5521_set_engine_mode(struct lp5521_engine *engine, u8 mode)
164 {
165 struct lp5521_chip *chip = engine_to_lp5521(engine);
166 struct i2c_client *client = chip->client;
167 int ret;
168 u8 engine_state;
169
170 /* Only transition between RUN and DIRECT mode are handled here */
171 if (mode == LP5521_CMD_LOAD)
172 return 0;
173
174 if (mode == LP5521_CMD_DISABLED)
175 mode = LP5521_CMD_DIRECT;
176
177 ret = lp5521_read(client, LP5521_REG_OP_MODE, &engine_state);
178
179 /* set mode only for this engine */
180 engine_state &= ~(engine->engine_mask);
181 mode &= engine->engine_mask;
182 engine_state |= mode;
183 ret |= lp5521_write(client, LP5521_REG_OP_MODE, engine_state);
184
185 return ret;
186 }
187
188 static int lp5521_load_program(struct lp5521_engine *eng, const u8 *pattern)
189 {
190 struct lp5521_chip *chip = engine_to_lp5521(eng);
191 struct i2c_client *client = chip->client;
192 int ret;
193 int addr;
194 u8 mode;
195
196 /* move current engine to direct mode and remember the state */
197 ret = lp5521_set_engine_mode(eng, LP5521_CMD_DIRECT);
198 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
199 usleep_range(1000, 2000);
200 ret |= lp5521_read(client, LP5521_REG_OP_MODE, &mode);
201
202 /* For loading, all the engines to load mode */
203 lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
204 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
205 usleep_range(1000, 2000);
206 lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
207 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
208 usleep_range(1000, 2000);
209
210 addr = LP5521_PROG_MEM_BASE + eng->prog_page * LP5521_PROG_MEM_SIZE;
211 i2c_smbus_write_i2c_block_data(client,
212 addr,
213 LP5521_PROG_MEM_SIZE,
214 pattern);
215
216 ret |= lp5521_write(client, LP5521_REG_OP_MODE, mode);
217 return ret;
218 }
219
220 static int lp5521_set_led_current(struct lp5521_chip *chip, int led, u8 curr)
221 {
222 return lp5521_write(chip->client,
223 LP5521_REG_LED_CURRENT_BASE + chip->leds[led].chan_nr,
224 curr);
225 }
226
227 static void lp5521_init_engine(struct lp5521_chip *chip)
228 {
229 int i;
230 for (i = 0; i < ARRAY_SIZE(chip->engines); i++) {
231 chip->engines[i].id = i + 1;
232 chip->engines[i].engine_mask = LP5521_ENG_MASK_BASE >> (i * 2);
233 chip->engines[i].prog_page = i;
234 }
235 }
236
237 static int lp5521_configure(struct i2c_client *client)
238 {
239 struct lp5521_chip *chip = i2c_get_clientdata(client);
240 int ret;
241
242 lp5521_init_engine(chip);
243
244 /* Set all PWMs to direct control mode */
245 ret = lp5521_write(client, LP5521_REG_OP_MODE, 0x3F);
246
247 /* Enable auto-powersave, set charge pump to auto, red to battery */
248 ret |= lp5521_write(client, LP5521_REG_CONFIG,
249 LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO | LP5521_R_TO_BATT);
250
251 /* Initialize all channels PWM to zero -> leds off */
252 ret |= lp5521_write(client, LP5521_REG_R_PWM, 0);
253 ret |= lp5521_write(client, LP5521_REG_G_PWM, 0);
254 ret |= lp5521_write(client, LP5521_REG_B_PWM, 0);
255
256 /* Set engines are set to run state when OP_MODE enables engines */
257 ret |= lp5521_write(client, LP5521_REG_ENABLE,
258 LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM |
259 LP5521_EXEC_RUN);
260 /* enable takes 500us. 1 - 2 ms leaves some margin */
261 usleep_range(1000, 2000);
262
263 return ret;
264 }
265
266 static int lp5521_run_selftest(struct lp5521_chip *chip, char *buf)
267 {
268 int ret;
269 u8 status;
270
271 ret = lp5521_read(chip->client, LP5521_REG_STATUS, &status);
272 if (ret < 0)
273 return ret;
274
275 /* Check that ext clock is really in use if requested */
276 if (chip->pdata && chip->pdata->clock_mode == LP5521_CLOCK_EXT)
277 if ((status & LP5521_EXT_CLK_USED) == 0)
278 return -EIO;
279 return 0;
280 }
281
282 static void lp5521_set_brightness(struct led_classdev *cdev,
283 enum led_brightness brightness)
284 {
285 struct lp5521_led *led = cdev_to_led(cdev);
286 led->brightness = (u8)brightness;
287 schedule_work(&led->brightness_work);
288 }
289
290 static void lp5521_led_brightness_work(struct work_struct *work)
291 {
292 struct lp5521_led *led = container_of(work,
293 struct lp5521_led,
294 brightness_work);
295 struct lp5521_chip *chip = led_to_lp5521(led);
296 struct i2c_client *client = chip->client;
297
298 mutex_lock(&chip->lock);
299 lp5521_write(client, LP5521_REG_LED_PWM_BASE + led->chan_nr,
300 led->brightness);
301 mutex_unlock(&chip->lock);
302 }
303
304 /* Detect the chip by setting its ENABLE register and reading it back. */
305 static int lp5521_detect(struct i2c_client *client)
306 {
307 int ret;
308 u8 buf;
309
310 ret = lp5521_write(client, LP5521_REG_ENABLE,
311 LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM);
312 if (ret)
313 return ret;
314 /* enable takes 500us. 1 - 2 ms leaves some margin */
315 usleep_range(1000, 2000);
316 ret = lp5521_read(client, LP5521_REG_ENABLE, &buf);
317 if (ret)
318 return ret;
319 if (buf != (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM))
320 return -ENODEV;
321
322 return 0;
323 }
324
325 /* Set engine mode and create appropriate sysfs attributes, if required. */
326 static int lp5521_set_mode(struct lp5521_engine *engine, u8 mode)
327 {
328 int ret = 0;
329
330 /* if in that mode already do nothing, except for run */
331 if (mode == engine->mode && mode != LP5521_CMD_RUN)
332 return 0;
333
334 if (mode == LP5521_CMD_RUN) {
335 ret = lp5521_set_engine_mode(engine, LP5521_CMD_RUN);
336 } else if (mode == LP5521_CMD_LOAD) {
337 lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
338 lp5521_set_engine_mode(engine, LP5521_CMD_LOAD);
339 } else if (mode == LP5521_CMD_DISABLED) {
340 lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
341 }
342
343 engine->mode = mode;
344
345 return ret;
346 }
347
348 static int lp5521_do_store_load(struct lp5521_engine *engine,
349 const char *buf, size_t len)
350 {
351 struct lp5521_chip *chip = engine_to_lp5521(engine);
352 struct i2c_client *client = chip->client;
353 int ret, nrchars, offset = 0, i = 0;
354 char c[3];
355 unsigned cmd;
356 u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
357
358 while ((offset < len - 1) && (i < LP5521_PROGRAM_LENGTH)) {
359 /* separate sscanfs because length is working only for %s */
360 ret = sscanf(buf + offset, "%2s%n ", c, &nrchars);
361 if (ret != 2)
362 goto fail;
363 ret = sscanf(c, "%2x", &cmd);
364 if (ret != 1)
365 goto fail;
366 pattern[i] = (u8)cmd;
367
368 offset += nrchars;
369 i++;
370 }
371
372 /* Each instruction is 16bit long. Check that length is even */
373 if (i % 2)
374 goto fail;
375
376 mutex_lock(&chip->lock);
377 if (engine->mode == LP5521_CMD_LOAD)
378 ret = lp5521_load_program(engine, pattern);
379 else
380 ret = -EINVAL;
381 mutex_unlock(&chip->lock);
382
383 if (ret) {
384 dev_err(&client->dev, "failed loading pattern\n");
385 return ret;
386 }
387
388 return len;
389 fail:
390 dev_err(&client->dev, "wrong pattern format\n");
391 return -EINVAL;
392 }
393
394 static ssize_t store_engine_load(struct device *dev,
395 struct device_attribute *attr,
396 const char *buf, size_t len, int nr)
397 {
398 struct i2c_client *client = to_i2c_client(dev);
399 struct lp5521_chip *chip = i2c_get_clientdata(client);
400 return lp5521_do_store_load(&chip->engines[nr - 1], buf, len);
401 }
402
403 #define store_load(nr) \
404 static ssize_t store_engine##nr##_load(struct device *dev, \
405 struct device_attribute *attr, \
406 const char *buf, size_t len) \
407 { \
408 return store_engine_load(dev, attr, buf, len, nr); \
409 }
410 store_load(1)
411 store_load(2)
412 store_load(3)
413
414 static ssize_t show_engine_mode(struct device *dev,
415 struct device_attribute *attr,
416 char *buf, int nr)
417 {
418 struct i2c_client *client = to_i2c_client(dev);
419 struct lp5521_chip *chip = i2c_get_clientdata(client);
420 switch (chip->engines[nr - 1].mode) {
421 case LP5521_CMD_RUN:
422 return sprintf(buf, "run\n");
423 case LP5521_CMD_LOAD:
424 return sprintf(buf, "load\n");
425 case LP5521_CMD_DISABLED:
426 return sprintf(buf, "disabled\n");
427 default:
428 return sprintf(buf, "disabled\n");
429 }
430 }
431
432 #define show_mode(nr) \
433 static ssize_t show_engine##nr##_mode(struct device *dev, \
434 struct device_attribute *attr, \
435 char *buf) \
436 { \
437 return show_engine_mode(dev, attr, buf, nr); \
438 }
439 show_mode(1)
440 show_mode(2)
441 show_mode(3)
442
443 static ssize_t store_engine_mode(struct device *dev,
444 struct device_attribute *attr,
445 const char *buf, size_t len, int nr)
446 {
447 struct i2c_client *client = to_i2c_client(dev);
448 struct lp5521_chip *chip = i2c_get_clientdata(client);
449 struct lp5521_engine *engine = &chip->engines[nr - 1];
450 mutex_lock(&chip->lock);
451
452 if (!strncmp(buf, "run", 3))
453 lp5521_set_mode(engine, LP5521_CMD_RUN);
454 else if (!strncmp(buf, "load", 4))
455 lp5521_set_mode(engine, LP5521_CMD_LOAD);
456 else if (!strncmp(buf, "disabled", 8))
457 lp5521_set_mode(engine, LP5521_CMD_DISABLED);
458
459 mutex_unlock(&chip->lock);
460 return len;
461 }
462
463 #define store_mode(nr) \
464 static ssize_t store_engine##nr##_mode(struct device *dev, \
465 struct device_attribute *attr, \
466 const char *buf, size_t len) \
467 { \
468 return store_engine_mode(dev, attr, buf, len, nr); \
469 }
470 store_mode(1)
471 store_mode(2)
472 store_mode(3)
473
474 static ssize_t show_max_current(struct device *dev,
475 struct device_attribute *attr,
476 char *buf)
477 {
478 struct led_classdev *led_cdev = dev_get_drvdata(dev);
479 struct lp5521_led *led = cdev_to_led(led_cdev);
480
481 return sprintf(buf, "%d\n", led->max_current);
482 }
483
484 static ssize_t show_current(struct device *dev,
485 struct device_attribute *attr,
486 char *buf)
487 {
488 struct led_classdev *led_cdev = dev_get_drvdata(dev);
489 struct lp5521_led *led = cdev_to_led(led_cdev);
490
491 return sprintf(buf, "%d\n", led->led_current);
492 }
493
494 static ssize_t store_current(struct device *dev,
495 struct device_attribute *attr,
496 const char *buf, size_t len)
497 {
498 struct led_classdev *led_cdev = dev_get_drvdata(dev);
499 struct lp5521_led *led = cdev_to_led(led_cdev);
500 struct lp5521_chip *chip = led_to_lp5521(led);
501 ssize_t ret;
502 unsigned long curr;
503
504 if (strict_strtoul(buf, 0, &curr))
505 return -EINVAL;
506
507 if (curr > led->max_current)
508 return -EINVAL;
509
510 mutex_lock(&chip->lock);
511 ret = lp5521_set_led_current(chip, led->id, curr);
512 mutex_unlock(&chip->lock);
513
514 if (ret < 0)
515 return ret;
516
517 led->led_current = (u8)curr;
518
519 return len;
520 }
521
522 static ssize_t lp5521_selftest(struct device *dev,
523 struct device_attribute *attr,
524 char *buf)
525 {
526 struct i2c_client *client = to_i2c_client(dev);
527 struct lp5521_chip *chip = i2c_get_clientdata(client);
528 int ret;
529
530 mutex_lock(&chip->lock);
531 ret = lp5521_run_selftest(chip, buf);
532 mutex_unlock(&chip->lock);
533 return sprintf(buf, "%s\n", ret ? "FAIL" : "OK");
534 }
535
536 /* led class device attributes */
537 static DEVICE_ATTR(led_current, S_IRUGO | S_IWUSR, show_current, store_current);
538 static DEVICE_ATTR(max_current, S_IRUGO , show_max_current, NULL);
539
540 static struct attribute *lp5521_led_attributes[] = {
541 &dev_attr_led_current.attr,
542 &dev_attr_max_current.attr,
543 NULL,
544 };
545
546 static struct attribute_group lp5521_led_attribute_group = {
547 .attrs = lp5521_led_attributes
548 };
549
550 /* device attributes */
551 static DEVICE_ATTR(engine1_mode, S_IRUGO | S_IWUSR,
552 show_engine1_mode, store_engine1_mode);
553 static DEVICE_ATTR(engine2_mode, S_IRUGO | S_IWUSR,
554 show_engine2_mode, store_engine2_mode);
555 static DEVICE_ATTR(engine3_mode, S_IRUGO | S_IWUSR,
556 show_engine3_mode, store_engine3_mode);
557 static DEVICE_ATTR(engine1_load, S_IWUSR, NULL, store_engine1_load);
558 static DEVICE_ATTR(engine2_load, S_IWUSR, NULL, store_engine2_load);
559 static DEVICE_ATTR(engine3_load, S_IWUSR, NULL, store_engine3_load);
560 static DEVICE_ATTR(selftest, S_IRUGO, lp5521_selftest, NULL);
561
562 static struct attribute *lp5521_attributes[] = {
563 &dev_attr_engine1_mode.attr,
564 &dev_attr_engine2_mode.attr,
565 &dev_attr_engine3_mode.attr,
566 &dev_attr_selftest.attr,
567 &dev_attr_engine1_load.attr,
568 &dev_attr_engine2_load.attr,
569 &dev_attr_engine3_load.attr,
570 NULL
571 };
572
573 static const struct attribute_group lp5521_group = {
574 .attrs = lp5521_attributes,
575 };
576
577 static int lp5521_register_sysfs(struct i2c_client *client)
578 {
579 struct device *dev = &client->dev;
580 return sysfs_create_group(&dev->kobj, &lp5521_group);
581 }
582
583 static void lp5521_unregister_sysfs(struct i2c_client *client)
584 {
585 struct lp5521_chip *chip = i2c_get_clientdata(client);
586 struct device *dev = &client->dev;
587 int i;
588
589 sysfs_remove_group(&dev->kobj, &lp5521_group);
590
591 for (i = 0; i < chip->num_leds; i++)
592 sysfs_remove_group(&chip->leds[i].cdev.dev->kobj,
593 &lp5521_led_attribute_group);
594 }
595
596 static int __devinit lp5521_init_led(struct lp5521_led *led,
597 struct i2c_client *client,
598 int chan, struct lp5521_platform_data *pdata)
599 {
600 struct device *dev = &client->dev;
601 char name[32];
602 int res;
603
604 if (chan >= LP5521_MAX_LEDS)
605 return -EINVAL;
606
607 if (pdata->led_config[chan].led_current == 0)
608 return 0;
609
610 led->led_current = pdata->led_config[chan].led_current;
611 led->max_current = pdata->led_config[chan].max_current;
612 led->chan_nr = pdata->led_config[chan].chan_nr;
613
614 if (led->chan_nr >= LP5521_MAX_LEDS) {
615 dev_err(dev, "Use channel numbers between 0 and %d\n",
616 LP5521_MAX_LEDS - 1);
617 return -EINVAL;
618 }
619
620 snprintf(name, sizeof(name), "%s:channel%d",
621 pdata->label ?: client->name, chan);
622 led->cdev.brightness_set = lp5521_set_brightness;
623 led->cdev.name = name;
624 res = led_classdev_register(dev, &led->cdev);
625 if (res < 0) {
626 dev_err(dev, "couldn't register led on channel %d\n", chan);
627 return res;
628 }
629
630 res = sysfs_create_group(&led->cdev.dev->kobj,
631 &lp5521_led_attribute_group);
632 if (res < 0) {
633 dev_err(dev, "couldn't register current attribute\n");
634 led_classdev_unregister(&led->cdev);
635 return res;
636 }
637 return 0;
638 }
639
640 static int __devinit lp5521_probe(struct i2c_client *client,
641 const struct i2c_device_id *id)
642 {
643 struct lp5521_chip *chip;
644 struct lp5521_platform_data *pdata;
645 int ret, i, led;
646
647 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
648 if (!chip)
649 return -ENOMEM;
650
651 i2c_set_clientdata(client, chip);
652 chip->client = client;
653
654 pdata = client->dev.platform_data;
655
656 if (!pdata) {
657 dev_err(&client->dev, "no platform data\n");
658 ret = -EINVAL;
659 goto fail1;
660 }
661
662 mutex_init(&chip->lock);
663
664 chip->pdata = pdata;
665
666 if (pdata->setup_resources) {
667 ret = pdata->setup_resources();
668 if (ret < 0)
669 goto fail1;
670 }
671
672 if (pdata->enable) {
673 pdata->enable(0);
674 usleep_range(1000, 2000); /* Keep enable down at least 1ms */
675 pdata->enable(1);
676 usleep_range(1000, 2000); /* 500us abs min. */
677 }
678
679 lp5521_write(client, LP5521_REG_RESET, 0xff);
680 usleep_range(10000, 20000); /*
681 * Exact value is not available. 10 - 20ms
682 * appears to be enough for reset.
683 */
684 ret = lp5521_detect(client);
685
686 if (ret) {
687 dev_err(&client->dev, "Chip not found\n");
688 goto fail2;
689 }
690
691 dev_info(&client->dev, "%s programmable led chip found\n", id->name);
692
693 ret = lp5521_configure(client);
694 if (ret < 0) {
695 dev_err(&client->dev, "error configuring chip\n");
696 goto fail2;
697 }
698
699 /* Initialize leds */
700 chip->num_channels = pdata->num_channels;
701 chip->num_leds = 0;
702 led = 0;
703 for (i = 0; i < pdata->num_channels; i++) {
704 /* Do not initialize channels that are not connected */
705 if (pdata->led_config[i].led_current == 0)
706 continue;
707
708 ret = lp5521_init_led(&chip->leds[led], client, i, pdata);
709 if (ret) {
710 dev_err(&client->dev, "error initializing leds\n");
711 goto fail3;
712 }
713 chip->num_leds++;
714
715 chip->leds[led].id = led;
716 /* Set initial LED current */
717 lp5521_set_led_current(chip, led,
718 chip->leds[led].led_current);
719
720 INIT_WORK(&(chip->leds[led].brightness_work),
721 lp5521_led_brightness_work);
722
723 led++;
724 }
725
726 ret = lp5521_register_sysfs(client);
727 if (ret) {
728 dev_err(&client->dev, "registering sysfs failed\n");
729 goto fail3;
730 }
731 return ret;
732 fail3:
733 for (i = 0; i < chip->num_leds; i++) {
734 led_classdev_unregister(&chip->leds[i].cdev);
735 cancel_work_sync(&chip->leds[i].brightness_work);
736 }
737 fail2:
738 if (pdata->enable)
739 pdata->enable(0);
740 if (pdata->release_resources)
741 pdata->release_resources();
742 fail1:
743 kfree(chip);
744 return ret;
745 }
746
747 static int __devexit lp5521_remove(struct i2c_client *client)
748 {
749 struct lp5521_chip *chip = i2c_get_clientdata(client);
750 int i;
751
752 lp5521_unregister_sysfs(client);
753
754 for (i = 0; i < chip->num_leds; i++) {
755 led_classdev_unregister(&chip->leds[i].cdev);
756 cancel_work_sync(&chip->leds[i].brightness_work);
757 }
758
759 if (chip->pdata->enable)
760 chip->pdata->enable(0);
761 if (chip->pdata->release_resources)
762 chip->pdata->release_resources();
763 kfree(chip);
764 return 0;
765 }
766
767 static const struct i2c_device_id lp5521_id[] = {
768 { "lp5521", 0 }, /* Three channel chip */
769 { }
770 };
771 MODULE_DEVICE_TABLE(i2c, lp5521_id);
772
773 static struct i2c_driver lp5521_driver = {
774 .driver = {
775 .name = "lp5521",
776 },
777 .probe = lp5521_probe,
778 .remove = __devexit_p(lp5521_remove),
779 .id_table = lp5521_id,
780 };
781
782 static int __init lp5521_init(void)
783 {
784 int ret;
785
786 ret = i2c_add_driver(&lp5521_driver);
787
788 if (ret < 0)
789 printk(KERN_ALERT "Adding lp5521 driver failed\n");
790
791 return ret;
792 }
793
794 static void __exit lp5521_exit(void)
795 {
796 i2c_del_driver(&lp5521_driver);
797 }
798
799 module_init(lp5521_init);
800 module_exit(lp5521_exit);
801
802 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
803 MODULE_DESCRIPTION("LP5521 LED engine");
804 MODULE_LICENSE("GPL v2");
linux-next