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Samu Onkalo500fe142010-11-11 14:05:22 -08001/*
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
100struct lp5521_engine {
101 const struct attribute_group *attributes;
102 int id;
103 u8 mode;
104 u8 prog_page;
105 u8 engine_mask;
106};
107
108struct lp5521_led {
109 int id;
110 u8 chan_nr;
111 u8 led_current;
112 u8 max_current;
113 struct led_classdev cdev;
114 struct work_struct brightness_work;
115 u8 brightness;
116};
117
118struct lp5521_chip {
119 struct lp5521_platform_data *pdata;
120 struct mutex lock; /* Serialize control */
121 struct i2c_client *client;
122 struct lp5521_engine engines[LP5521_MAX_ENGINES];
123 struct lp5521_led leds[LP5521_MAX_LEDS];
124 u8 num_channels;
125 u8 num_leds;
126};
127
Samu Onkalo9fdb18b2010-11-24 12:57:02 -0800128static inline struct lp5521_led *cdev_to_led(struct led_classdev *cdev)
129{
130 return container_of(cdev, struct lp5521_led, cdev);
131}
132
133static inline struct lp5521_chip *engine_to_lp5521(struct lp5521_engine *engine)
134{
135 return container_of(engine, struct lp5521_chip,
136 engines[engine->id - 1]);
137}
138
139static inline struct lp5521_chip *led_to_lp5521(struct lp5521_led *led)
140{
141 return container_of(led, struct lp5521_chip,
142 leds[led->id]);
143}
Samu Onkalo500fe142010-11-11 14:05:22 -0800144
145static void lp5521_led_brightness_work(struct work_struct *work);
146
147static inline int lp5521_write(struct i2c_client *client, u8 reg, u8 value)
148{
149 return i2c_smbus_write_byte_data(client, reg, value);
150}
151
152static int lp5521_read(struct i2c_client *client, u8 reg, u8 *buf)
153{
154 s32 ret;
155
156 ret = i2c_smbus_read_byte_data(client, reg);
157 if (ret < 0)
158 return -EIO;
159
160 *buf = ret;
161 return 0;
162}
163
164static int lp5521_set_engine_mode(struct lp5521_engine *engine, u8 mode)
165{
166 struct lp5521_chip *chip = engine_to_lp5521(engine);
167 struct i2c_client *client = chip->client;
168 int ret;
169 u8 engine_state;
170
171 /* Only transition between RUN and DIRECT mode are handled here */
172 if (mode == LP5521_CMD_LOAD)
173 return 0;
174
175 if (mode == LP5521_CMD_DISABLED)
176 mode = LP5521_CMD_DIRECT;
177
178 ret = lp5521_read(client, LP5521_REG_OP_MODE, &engine_state);
179
180 /* set mode only for this engine */
181 engine_state &= ~(engine->engine_mask);
182 mode &= engine->engine_mask;
183 engine_state |= mode;
184 ret |= lp5521_write(client, LP5521_REG_OP_MODE, engine_state);
185
186 return ret;
187}
188
189static int lp5521_load_program(struct lp5521_engine *eng, const u8 *pattern)
190{
191 struct lp5521_chip *chip = engine_to_lp5521(eng);
192 struct i2c_client *client = chip->client;
193 int ret;
194 int addr;
195 u8 mode;
196
197 /* move current engine to direct mode and remember the state */
198 ret = lp5521_set_engine_mode(eng, LP5521_CMD_DIRECT);
Samu Onkalo09c76b02010-11-24 12:57:03 -0800199 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
200 usleep_range(1000, 2000);
Samu Onkalo500fe142010-11-11 14:05:22 -0800201 ret |= lp5521_read(client, LP5521_REG_OP_MODE, &mode);
202
203 /* For loading, all the engines to load mode */
204 lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
Samu Onkalo09c76b02010-11-24 12:57:03 -0800205 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
206 usleep_range(1000, 2000);
Samu Onkalo500fe142010-11-11 14:05:22 -0800207 lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
Samu Onkalo09c76b02010-11-24 12:57:03 -0800208 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
209 usleep_range(1000, 2000);
Samu Onkalo500fe142010-11-11 14:05:22 -0800210
211 addr = LP5521_PROG_MEM_BASE + eng->prog_page * LP5521_PROG_MEM_SIZE;
212 i2c_smbus_write_i2c_block_data(client,
213 addr,
214 LP5521_PROG_MEM_SIZE,
215 pattern);
216
217 ret |= lp5521_write(client, LP5521_REG_OP_MODE, mode);
218 return ret;
219}
220
221static int lp5521_set_led_current(struct lp5521_chip *chip, int led, u8 curr)
222{
223 return lp5521_write(chip->client,
224 LP5521_REG_LED_CURRENT_BASE + chip->leds[led].chan_nr,
225 curr);
226}
227
228static void lp5521_init_engine(struct lp5521_chip *chip,
229 const struct attribute_group *attr_group)
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 chip->engines[i].attributes = &attr_group[i];
237 }
238}
239
240static int lp5521_configure(struct i2c_client *client,
241 const struct attribute_group *attr_group)
242{
243 struct lp5521_chip *chip = i2c_get_clientdata(client);
244 int ret;
245
246 lp5521_init_engine(chip, attr_group);
247
Samu Onkalo500fe142010-11-11 14:05:22 -0800248 /* Set all PWMs to direct control mode */
249 ret = lp5521_write(client, LP5521_REG_OP_MODE, 0x3F);
250
251 /* Enable auto-powersave, set charge pump to auto, red to battery */
252 ret |= lp5521_write(client, LP5521_REG_CONFIG,
253 LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO | LP5521_R_TO_BATT);
254
255 /* Initialize all channels PWM to zero -> leds off */
256 ret |= lp5521_write(client, LP5521_REG_R_PWM, 0);
257 ret |= lp5521_write(client, LP5521_REG_G_PWM, 0);
258 ret |= lp5521_write(client, LP5521_REG_B_PWM, 0);
259
260 /* Set engines are set to run state when OP_MODE enables engines */
261 ret |= lp5521_write(client, LP5521_REG_ENABLE,
262 LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM |
263 LP5521_EXEC_RUN);
Samu Onkalo09c76b02010-11-24 12:57:03 -0800264 /* enable takes 500us. 1 - 2 ms leaves some margin */
265 usleep_range(1000, 2000);
Samu Onkalo500fe142010-11-11 14:05:22 -0800266
267 return ret;
268}
269
270static int lp5521_run_selftest(struct lp5521_chip *chip, char *buf)
271{
272 int ret;
273 u8 status;
274
275 ret = lp5521_read(chip->client, LP5521_REG_STATUS, &status);
276 if (ret < 0)
277 return ret;
278
279 /* Check that ext clock is really in use if requested */
280 if (chip->pdata && chip->pdata->clock_mode == LP5521_CLOCK_EXT)
281 if ((status & LP5521_EXT_CLK_USED) == 0)
282 return -EIO;
283 return 0;
284}
285
286static void lp5521_set_brightness(struct led_classdev *cdev,
287 enum led_brightness brightness)
288{
289 struct lp5521_led *led = cdev_to_led(cdev);
290 led->brightness = (u8)brightness;
291 schedule_work(&led->brightness_work);
292}
293
294static void lp5521_led_brightness_work(struct work_struct *work)
295{
296 struct lp5521_led *led = container_of(work,
297 struct lp5521_led,
298 brightness_work);
299 struct lp5521_chip *chip = led_to_lp5521(led);
300 struct i2c_client *client = chip->client;
301
302 mutex_lock(&chip->lock);
303 lp5521_write(client, LP5521_REG_LED_PWM_BASE + led->chan_nr,
304 led->brightness);
305 mutex_unlock(&chip->lock);
306}
307
308/* Detect the chip by setting its ENABLE register and reading it back. */
309static int lp5521_detect(struct i2c_client *client)
310{
311 int ret;
312 u8 buf;
313
314 ret = lp5521_write(client, LP5521_REG_ENABLE,
315 LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM);
316 if (ret)
317 return ret;
Samu Onkalo09c76b02010-11-24 12:57:03 -0800318 /* enable takes 500us. 1 - 2 ms leaves some margin */
319 usleep_range(1000, 2000);
Samu Onkalo500fe142010-11-11 14:05:22 -0800320 ret = lp5521_read(client, LP5521_REG_ENABLE, &buf);
321 if (ret)
322 return ret;
323 if (buf != (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM))
324 return -ENODEV;
325
326 return 0;
327}
328
329/* Set engine mode and create appropriate sysfs attributes, if required. */
330static int lp5521_set_mode(struct lp5521_engine *engine, u8 mode)
331{
332 struct lp5521_chip *chip = engine_to_lp5521(engine);
333 struct i2c_client *client = chip->client;
334 struct device *dev = &client->dev;
335 int ret = 0;
336
337 /* if in that mode already do nothing, except for run */
338 if (mode == engine->mode && mode != LP5521_CMD_RUN)
339 return 0;
340
341 if (mode == LP5521_CMD_RUN) {
342 ret = lp5521_set_engine_mode(engine, LP5521_CMD_RUN);
343 } else if (mode == LP5521_CMD_LOAD) {
344 lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
345 lp5521_set_engine_mode(engine, LP5521_CMD_LOAD);
346
347 ret = sysfs_create_group(&dev->kobj, engine->attributes);
348 if (ret)
349 return ret;
350 } else if (mode == LP5521_CMD_DISABLED) {
351 lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
352 }
353
354 /* remove load attribute from sysfs if not in load mode */
355 if (engine->mode == LP5521_CMD_LOAD && mode != LP5521_CMD_LOAD)
356 sysfs_remove_group(&dev->kobj, engine->attributes);
357
358 engine->mode = mode;
359
360 return ret;
361}
362
363static int lp5521_do_store_load(struct lp5521_engine *engine,
364 const char *buf, size_t len)
365{
366 struct lp5521_chip *chip = engine_to_lp5521(engine);
367 struct i2c_client *client = chip->client;
368 int ret, nrchars, offset = 0, i = 0;
369 char c[3];
370 unsigned cmd;
371 u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
372
373 while ((offset < len - 1) && (i < LP5521_PROGRAM_LENGTH)) {
374 /* separate sscanfs because length is working only for %s */
375 ret = sscanf(buf + offset, "%2s%n ", c, &nrchars);
376 ret = sscanf(c, "%2x", &cmd);
377 if (ret != 1)
378 goto fail;
379 pattern[i] = (u8)cmd;
380
381 offset += nrchars;
382 i++;
383 }
384
385 /* Each instruction is 16bit long. Check that length is even */
386 if (i % 2)
387 goto fail;
388
389 mutex_lock(&chip->lock);
390 ret = lp5521_load_program(engine, pattern);
391 mutex_unlock(&chip->lock);
392
393 if (ret) {
394 dev_err(&client->dev, "failed loading pattern\n");
395 return ret;
396 }
397
398 return len;
399fail:
400 dev_err(&client->dev, "wrong pattern format\n");
401 return -EINVAL;
402}
403
404static ssize_t store_engine_load(struct device *dev,
405 struct device_attribute *attr,
406 const char *buf, size_t len, int nr)
407{
408 struct i2c_client *client = to_i2c_client(dev);
409 struct lp5521_chip *chip = i2c_get_clientdata(client);
410 return lp5521_do_store_load(&chip->engines[nr - 1], buf, len);
411}
412
413#define store_load(nr) \
414static ssize_t store_engine##nr##_load(struct device *dev, \
415 struct device_attribute *attr, \
416 const char *buf, size_t len) \
417{ \
418 return store_engine_load(dev, attr, buf, len, nr); \
419}
420store_load(1)
421store_load(2)
422store_load(3)
423
424static ssize_t show_engine_mode(struct device *dev,
425 struct device_attribute *attr,
426 char *buf, int nr)
427{
428 struct i2c_client *client = to_i2c_client(dev);
429 struct lp5521_chip *chip = i2c_get_clientdata(client);
430 switch (chip->engines[nr - 1].mode) {
431 case LP5521_CMD_RUN:
432 return sprintf(buf, "run\n");
433 case LP5521_CMD_LOAD:
434 return sprintf(buf, "load\n");
435 case LP5521_CMD_DISABLED:
436 return sprintf(buf, "disabled\n");
437 default:
438 return sprintf(buf, "disabled\n");
439 }
440}
441
442#define show_mode(nr) \
443static ssize_t show_engine##nr##_mode(struct device *dev, \
444 struct device_attribute *attr, \
445 char *buf) \
446{ \
447 return show_engine_mode(dev, attr, buf, nr); \
448}
449show_mode(1)
450show_mode(2)
451show_mode(3)
452
453static ssize_t store_engine_mode(struct device *dev,
454 struct device_attribute *attr,
455 const char *buf, size_t len, int nr)
456{
457 struct i2c_client *client = to_i2c_client(dev);
458 struct lp5521_chip *chip = i2c_get_clientdata(client);
459 struct lp5521_engine *engine = &chip->engines[nr - 1];
460 mutex_lock(&chip->lock);
461
462 if (!strncmp(buf, "run", 3))
463 lp5521_set_mode(engine, LP5521_CMD_RUN);
464 else if (!strncmp(buf, "load", 4))
465 lp5521_set_mode(engine, LP5521_CMD_LOAD);
466 else if (!strncmp(buf, "disabled", 8))
467 lp5521_set_mode(engine, LP5521_CMD_DISABLED);
468
469 mutex_unlock(&chip->lock);
470 return len;
471}
472
473#define store_mode(nr) \
474static ssize_t store_engine##nr##_mode(struct device *dev, \
475 struct device_attribute *attr, \
476 const char *buf, size_t len) \
477{ \
478 return store_engine_mode(dev, attr, buf, len, nr); \
479}
480store_mode(1)
481store_mode(2)
482store_mode(3)
483
484static ssize_t show_max_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->max_current);
492}
493
494static ssize_t show_current(struct device *dev,
495 struct device_attribute *attr,
496 char *buf)
497{
498 struct led_classdev *led_cdev = dev_get_drvdata(dev);
499 struct lp5521_led *led = cdev_to_led(led_cdev);
500
501 return sprintf(buf, "%d\n", led->led_current);
502}
503
504static ssize_t store_current(struct device *dev,
505 struct device_attribute *attr,
506 const char *buf, size_t len)
507{
508 struct led_classdev *led_cdev = dev_get_drvdata(dev);
509 struct lp5521_led *led = cdev_to_led(led_cdev);
510 struct lp5521_chip *chip = led_to_lp5521(led);
511 ssize_t ret;
512 unsigned long curr;
513
514 if (strict_strtoul(buf, 0, &curr))
515 return -EINVAL;
516
517 if (curr > led->max_current)
518 return -EINVAL;
519
520 mutex_lock(&chip->lock);
521 ret = lp5521_set_led_current(chip, led->id, curr);
522 mutex_unlock(&chip->lock);
523
524 if (ret < 0)
525 return ret;
526
527 led->led_current = (u8)curr;
528
529 return len;
530}
531
532static ssize_t lp5521_selftest(struct device *dev,
533 struct device_attribute *attr,
534 char *buf)
535{
536 struct i2c_client *client = to_i2c_client(dev);
537 struct lp5521_chip *chip = i2c_get_clientdata(client);
538 int ret;
539
540 mutex_lock(&chip->lock);
541 ret = lp5521_run_selftest(chip, buf);
542 mutex_unlock(&chip->lock);
543 return sprintf(buf, "%s\n", ret ? "FAIL" : "OK");
544}
545
546/* led class device attributes */
547static DEVICE_ATTR(led_current, S_IRUGO | S_IWUGO, show_current, store_current);
548static DEVICE_ATTR(max_current, S_IRUGO , show_max_current, NULL);
549
550static struct attribute *lp5521_led_attributes[] = {
551 &dev_attr_led_current.attr,
552 &dev_attr_max_current.attr,
553 NULL,
554};
555
556static struct attribute_group lp5521_led_attribute_group = {
557 .attrs = lp5521_led_attributes
558};
559
560/* device attributes */
561static DEVICE_ATTR(engine1_mode, S_IRUGO | S_IWUGO,
562 show_engine1_mode, store_engine1_mode);
563static DEVICE_ATTR(engine2_mode, S_IRUGO | S_IWUGO,
564 show_engine2_mode, store_engine2_mode);
565static DEVICE_ATTR(engine3_mode, S_IRUGO | S_IWUGO,
566 show_engine3_mode, store_engine3_mode);
567static DEVICE_ATTR(engine1_load, S_IWUGO, NULL, store_engine1_load);
568static DEVICE_ATTR(engine2_load, S_IWUGO, NULL, store_engine2_load);
569static DEVICE_ATTR(engine3_load, S_IWUGO, NULL, store_engine3_load);
570static DEVICE_ATTR(selftest, S_IRUGO, lp5521_selftest, NULL);
571
572static struct attribute *lp5521_attributes[] = {
573 &dev_attr_engine1_mode.attr,
574 &dev_attr_engine2_mode.attr,
575 &dev_attr_engine3_mode.attr,
576 &dev_attr_selftest.attr,
577 NULL
578};
579
580static struct attribute *lp5521_engine1_attributes[] = {
581 &dev_attr_engine1_load.attr,
582 NULL
583};
584
585static struct attribute *lp5521_engine2_attributes[] = {
586 &dev_attr_engine2_load.attr,
587 NULL
588};
589
590static struct attribute *lp5521_engine3_attributes[] = {
591 &dev_attr_engine3_load.attr,
592 NULL
593};
594
595static const struct attribute_group lp5521_group = {
596 .attrs = lp5521_attributes,
597};
598
599static const struct attribute_group lp5521_engine_group[] = {
600 {.attrs = lp5521_engine1_attributes },
601 {.attrs = lp5521_engine2_attributes },
602 {.attrs = lp5521_engine3_attributes },
603};
604
605static int lp5521_register_sysfs(struct i2c_client *client)
606{
607 struct device *dev = &client->dev;
608 return sysfs_create_group(&dev->kobj, &lp5521_group);
609}
610
611static void lp5521_unregister_sysfs(struct i2c_client *client)
612{
613 struct lp5521_chip *chip = i2c_get_clientdata(client);
614 struct device *dev = &client->dev;
615 int i;
616
617 sysfs_remove_group(&dev->kobj, &lp5521_group);
618
619 for (i = 0; i < ARRAY_SIZE(chip->engines); i++) {
620 if (chip->engines[i].mode == LP5521_CMD_LOAD)
621 sysfs_remove_group(&dev->kobj,
622 chip->engines[i].attributes);
623 }
624
625 for (i = 0; i < chip->num_leds; i++)
626 sysfs_remove_group(&chip->leds[i].cdev.dev->kobj,
627 &lp5521_led_attribute_group);
628}
629
630static int __init lp5521_init_led(struct lp5521_led *led,
631 struct i2c_client *client,
632 int chan, struct lp5521_platform_data *pdata)
633{
634 struct device *dev = &client->dev;
635 char name[32];
636 int res;
637
638 if (chan >= LP5521_MAX_LEDS)
639 return -EINVAL;
640
641 if (pdata->led_config[chan].led_current == 0)
642 return 0;
643
644 led->led_current = pdata->led_config[chan].led_current;
645 led->max_current = pdata->led_config[chan].max_current;
646 led->chan_nr = pdata->led_config[chan].chan_nr;
647
648 if (led->chan_nr >= LP5521_MAX_LEDS) {
649 dev_err(dev, "Use channel numbers between 0 and %d\n",
650 LP5521_MAX_LEDS - 1);
651 return -EINVAL;
652 }
653
654 snprintf(name, sizeof(name), "%s:channel%d", client->name, chan);
655 led->cdev.brightness_set = lp5521_set_brightness;
656 led->cdev.name = name;
657 res = led_classdev_register(dev, &led->cdev);
658 if (res < 0) {
659 dev_err(dev, "couldn't register led on channel %d\n", chan);
660 return res;
661 }
662
663 res = sysfs_create_group(&led->cdev.dev->kobj,
664 &lp5521_led_attribute_group);
665 if (res < 0) {
666 dev_err(dev, "couldn't register current attribute\n");
667 led_classdev_unregister(&led->cdev);
668 return res;
669 }
670 return 0;
671}
672
673static int lp5521_probe(struct i2c_client *client,
674 const struct i2c_device_id *id)
675{
676 struct lp5521_chip *chip;
677 struct lp5521_platform_data *pdata;
678 int ret, i, led;
679
680 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
681 if (!chip)
682 return -ENOMEM;
683
684 i2c_set_clientdata(client, chip);
685 chip->client = client;
686
687 pdata = client->dev.platform_data;
688
689 if (!pdata) {
690 dev_err(&client->dev, "no platform data\n");
691 ret = -EINVAL;
692 goto fail1;
693 }
694
695 mutex_init(&chip->lock);
696
697 chip->pdata = pdata;
698
699 if (pdata->setup_resources) {
700 ret = pdata->setup_resources();
701 if (ret < 0)
702 goto fail1;
703 }
704
705 if (pdata->enable) {
706 pdata->enable(0);
Samu Onkalo09c76b02010-11-24 12:57:03 -0800707 usleep_range(1000, 2000); /* Keep enable down at least 1ms */
Samu Onkalo500fe142010-11-11 14:05:22 -0800708 pdata->enable(1);
Samu Onkalo09c76b02010-11-24 12:57:03 -0800709 usleep_range(1000, 2000); /* 500us abs min. */
Samu Onkalo500fe142010-11-11 14:05:22 -0800710 }
711
Samu Onkalo95ea8ee2010-11-24 12:57:05 -0800712 lp5521_write(client, LP5521_REG_RESET, 0xff);
713 usleep_range(10000, 20000); /*
714 * Exact value is not available. 10 - 20ms
715 * appears to be enough for reset.
716 */
Samu Onkalo500fe142010-11-11 14:05:22 -0800717 ret = lp5521_detect(client);
718
719 if (ret) {
720 dev_err(&client->dev, "Chip not found\n");
721 goto fail2;
722 }
723
724 dev_info(&client->dev, "%s programmable led chip found\n", id->name);
725
726 ret = lp5521_configure(client, lp5521_engine_group);
727 if (ret < 0) {
728 dev_err(&client->dev, "error configuring chip\n");
729 goto fail2;
730 }
731
732 /* Initialize leds */
733 chip->num_channels = pdata->num_channels;
734 chip->num_leds = 0;
735 led = 0;
736 for (i = 0; i < pdata->num_channels; i++) {
737 /* Do not initialize channels that are not connected */
738 if (pdata->led_config[i].led_current == 0)
739 continue;
740
741 ret = lp5521_init_led(&chip->leds[led], client, i, pdata);
742 if (ret) {
743 dev_err(&client->dev, "error initializing leds\n");
744 goto fail3;
745 }
746 chip->num_leds++;
747
748 chip->leds[led].id = led;
749 /* Set initial LED current */
750 lp5521_set_led_current(chip, led,
751 chip->leds[led].led_current);
752
753 INIT_WORK(&(chip->leds[led].brightness_work),
754 lp5521_led_brightness_work);
755
756 led++;
757 }
758
759 ret = lp5521_register_sysfs(client);
760 if (ret) {
761 dev_err(&client->dev, "registering sysfs failed\n");
762 goto fail3;
763 }
764 return ret;
765fail3:
766 for (i = 0; i < chip->num_leds; i++) {
767 led_classdev_unregister(&chip->leds[i].cdev);
768 cancel_work_sync(&chip->leds[i].brightness_work);
769 }
770fail2:
771 if (pdata->enable)
772 pdata->enable(0);
773 if (pdata->release_resources)
774 pdata->release_resources();
775fail1:
776 kfree(chip);
777 return ret;
778}
779
780static int lp5521_remove(struct i2c_client *client)
781{
782 struct lp5521_chip *chip = i2c_get_clientdata(client);
783 int i;
784
785 lp5521_unregister_sysfs(client);
786
787 for (i = 0; i < chip->num_leds; i++) {
788 led_classdev_unregister(&chip->leds[i].cdev);
789 cancel_work_sync(&chip->leds[i].brightness_work);
790 }
791
792 if (chip->pdata->enable)
793 chip->pdata->enable(0);
794 if (chip->pdata->release_resources)
795 chip->pdata->release_resources();
796 kfree(chip);
797 return 0;
798}
799
800static const struct i2c_device_id lp5521_id[] = {
801 { "lp5521", 0 }, /* Three channel chip */
802 { }
803};
804MODULE_DEVICE_TABLE(i2c, lp5521_id);
805
806static struct i2c_driver lp5521_driver = {
807 .driver = {
808 .name = "lp5521",
809 },
810 .probe = lp5521_probe,
811 .remove = lp5521_remove,
812 .id_table = lp5521_id,
813};
814
815static int __init lp5521_init(void)
816{
817 int ret;
818
819 ret = i2c_add_driver(&lp5521_driver);
820
821 if (ret < 0)
822 printk(KERN_ALERT "Adding lp5521 driver failed\n");
823
824 return ret;
825}
826
827static void __exit lp5521_exit(void)
828{
829 i2c_del_driver(&lp5521_driver);
830}
831
832module_init(lp5521_init);
833module_exit(lp5521_exit);
834
835MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
836MODULE_DESCRIPTION("LP5521 LED engine");
837MODULE_LICENSE("GPL v2");