2 * LP5521 LED chip driver.
4 * Copyright (C) 2010 Nokia Corporation
6 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
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.
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.
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
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>
38 #define LP5521_PROGRAM_LENGTH 32 /* in bytes */
40 #define LP5521_MAX_LEDS 3 /* Maximum number of LEDs */
41 #define LP5521_MAX_ENGINES 3 /* Maximum number of engines */
43 #define LP5521_ENG_MASK_BASE 0x30 /* 00110000 */
44 #define LP5521_ENG_STATUS_MASK 0x07 /* 00000111 */
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 */
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
71 #define LP5521_PROG_MEM_BASE LP5521_REG_R_PROG_MEM
72 #define LP5521_PROG_MEM_SIZE 0x20
74 /* Base register to set LED current */
75 #define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT
77 /* Base register to set the brightness */
78 #define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM
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
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 */
98 #define LP5521_EXT_CLK_USED 0x08
100 struct lp5521_engine {
101 const struct attribute_group *attributes;
113 struct led_classdev cdev;
114 struct work_struct brightness_work;
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];
128 static inline struct lp5521_led *cdev_to_led(struct led_classdev *cdev)
130 return container_of(cdev, struct lp5521_led, cdev);
133 static inline struct lp5521_chip *engine_to_lp5521(struct lp5521_engine *engine)
135 return container_of(engine, struct lp5521_chip,
136 engines[engine->id - 1]);
139 static inline struct lp5521_chip *led_to_lp5521(struct lp5521_led *led)
141 return container_of(led, struct lp5521_chip,
145 static void lp5521_led_brightness_work(struct work_struct *work);
147 static inline int lp5521_write(struct i2c_client *client, u8 reg, u8 value)
149 return i2c_smbus_write_byte_data(client, reg, value);
152 static int lp5521_read(struct i2c_client *client, u8 reg, u8 *buf)
156 ret = i2c_smbus_read_byte_data(client, reg);
164 static int lp5521_set_engine_mode(struct lp5521_engine *engine, u8 mode)
166 struct lp5521_chip *chip = engine_to_lp5521(engine);
167 struct i2c_client *client = chip->client;
171 /* Only transition between RUN and DIRECT mode are handled here */
172 if (mode == LP5521_CMD_LOAD)
175 if (mode == LP5521_CMD_DISABLED)
176 mode = LP5521_CMD_DIRECT;
178 ret = lp5521_read(client, LP5521_REG_OP_MODE, &engine_state);
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);
189 static int lp5521_load_program(struct lp5521_engine *eng, const u8 *pattern)
191 struct lp5521_chip *chip = engine_to_lp5521(eng);
192 struct i2c_client *client = chip->client;
197 /* move current engine to direct mode and remember the state */
198 ret = lp5521_set_engine_mode(eng, LP5521_CMD_DIRECT);
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);
203 /* For loading, all the engines to load mode */
204 lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
205 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
206 usleep_range(1000, 2000);
207 lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
208 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
209 usleep_range(1000, 2000);
211 addr = LP5521_PROG_MEM_BASE + eng->prog_page * LP5521_PROG_MEM_SIZE;
212 i2c_smbus_write_i2c_block_data(client,
214 LP5521_PROG_MEM_SIZE,
217 ret |= lp5521_write(client, LP5521_REG_OP_MODE, mode);
221 static int lp5521_set_led_current(struct lp5521_chip *chip, int led, u8 curr)
223 return lp5521_write(chip->client,
224 LP5521_REG_LED_CURRENT_BASE + chip->leds[led].chan_nr,
228 static void lp5521_init_engine(struct lp5521_chip *chip,
229 const struct attribute_group *attr_group)
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];
240 static int lp5521_configure(struct i2c_client *client,
241 const struct attribute_group *attr_group)
243 struct lp5521_chip *chip = i2c_get_clientdata(client);
246 lp5521_init_engine(chip, attr_group);
248 /* Set all PWMs to direct control mode */
249 ret = lp5521_write(client, LP5521_REG_OP_MODE, 0x3F);
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);
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);
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 |
264 /* enable takes 500us. 1 - 2 ms leaves some margin */
265 usleep_range(1000, 2000);
270 static int lp5521_run_selftest(struct lp5521_chip *chip, char *buf)
275 ret = lp5521_read(chip->client, LP5521_REG_STATUS, &status);
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)
286 static void lp5521_set_brightness(struct led_classdev *cdev,
287 enum led_brightness brightness)
289 struct lp5521_led *led = cdev_to_led(cdev);
290 led->brightness = (u8)brightness;
291 schedule_work(&led->brightness_work);
294 static void lp5521_led_brightness_work(struct work_struct *work)
296 struct lp5521_led *led = container_of(work,
299 struct lp5521_chip *chip = led_to_lp5521(led);
300 struct i2c_client *client = chip->client;
302 mutex_lock(&chip->lock);
303 lp5521_write(client, LP5521_REG_LED_PWM_BASE + led->chan_nr,
305 mutex_unlock(&chip->lock);
308 /* Detect the chip by setting its ENABLE register and reading it back. */
309 static int lp5521_detect(struct i2c_client *client)
314 ret = lp5521_write(client, LP5521_REG_ENABLE,
315 LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM);
318 /* enable takes 500us. 1 - 2 ms leaves some margin */
319 usleep_range(1000, 2000);
320 ret = lp5521_read(client, LP5521_REG_ENABLE, &buf);
323 if (buf != (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM))
329 /* Set engine mode and create appropriate sysfs attributes, if required. */
330 static int lp5521_set_mode(struct lp5521_engine *engine, u8 mode)
332 struct lp5521_chip *chip = engine_to_lp5521(engine);
333 struct i2c_client *client = chip->client;
334 struct device *dev = &client->dev;
337 /* if in that mode already do nothing, except for run */
338 if (mode == engine->mode && mode != LP5521_CMD_RUN)
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);
347 ret = sysfs_create_group(&dev->kobj, engine->attributes);
350 } else if (mode == LP5521_CMD_DISABLED) {
351 lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
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);
363 static int lp5521_do_store_load(struct lp5521_engine *engine,
364 const char *buf, size_t len)
366 struct lp5521_chip *chip = engine_to_lp5521(engine);
367 struct i2c_client *client = chip->client;
368 int ret, nrchars, offset = 0, i = 0;
371 u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
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);
378 ret = sscanf(c, "%2x", &cmd);
381 pattern[i] = (u8)cmd;
387 /* Each instruction is 16bit long. Check that length is even */
391 mutex_lock(&chip->lock);
392 ret = lp5521_load_program(engine, pattern);
393 mutex_unlock(&chip->lock);
396 dev_err(&client->dev, "failed loading pattern\n");
402 dev_err(&client->dev, "wrong pattern format\n");
406 static ssize_t store_engine_load(struct device *dev,
407 struct device_attribute *attr,
408 const char *buf, size_t len, int nr)
410 struct i2c_client *client = to_i2c_client(dev);
411 struct lp5521_chip *chip = i2c_get_clientdata(client);
412 return lp5521_do_store_load(&chip->engines[nr - 1], buf, len);
415 #define store_load(nr) \
416 static ssize_t store_engine##nr##_load(struct device *dev, \
417 struct device_attribute *attr, \
418 const char *buf, size_t len) \
420 return store_engine_load(dev, attr, buf, len, nr); \
426 static ssize_t show_engine_mode(struct device *dev,
427 struct device_attribute *attr,
430 struct i2c_client *client = to_i2c_client(dev);
431 struct lp5521_chip *chip = i2c_get_clientdata(client);
432 switch (chip->engines[nr - 1].mode) {
434 return sprintf(buf, "run\n");
435 case LP5521_CMD_LOAD:
436 return sprintf(buf, "load\n");
437 case LP5521_CMD_DISABLED:
438 return sprintf(buf, "disabled\n");
440 return sprintf(buf, "disabled\n");
444 #define show_mode(nr) \
445 static ssize_t show_engine##nr##_mode(struct device *dev, \
446 struct device_attribute *attr, \
449 return show_engine_mode(dev, attr, buf, nr); \
455 static ssize_t store_engine_mode(struct device *dev,
456 struct device_attribute *attr,
457 const char *buf, size_t len, int nr)
459 struct i2c_client *client = to_i2c_client(dev);
460 struct lp5521_chip *chip = i2c_get_clientdata(client);
461 struct lp5521_engine *engine = &chip->engines[nr - 1];
462 mutex_lock(&chip->lock);
464 if (!strncmp(buf, "run", 3))
465 lp5521_set_mode(engine, LP5521_CMD_RUN);
466 else if (!strncmp(buf, "load", 4))
467 lp5521_set_mode(engine, LP5521_CMD_LOAD);
468 else if (!strncmp(buf, "disabled", 8))
469 lp5521_set_mode(engine, LP5521_CMD_DISABLED);
471 mutex_unlock(&chip->lock);
475 #define store_mode(nr) \
476 static ssize_t store_engine##nr##_mode(struct device *dev, \
477 struct device_attribute *attr, \
478 const char *buf, size_t len) \
480 return store_engine_mode(dev, attr, buf, len, nr); \
486 static ssize_t show_max_current(struct device *dev,
487 struct device_attribute *attr,
490 struct led_classdev *led_cdev = dev_get_drvdata(dev);
491 struct lp5521_led *led = cdev_to_led(led_cdev);
493 return sprintf(buf, "%d\n", led->max_current);
496 static ssize_t show_current(struct device *dev,
497 struct device_attribute *attr,
500 struct led_classdev *led_cdev = dev_get_drvdata(dev);
501 struct lp5521_led *led = cdev_to_led(led_cdev);
503 return sprintf(buf, "%d\n", led->led_current);
506 static ssize_t store_current(struct device *dev,
507 struct device_attribute *attr,
508 const char *buf, size_t len)
510 struct led_classdev *led_cdev = dev_get_drvdata(dev);
511 struct lp5521_led *led = cdev_to_led(led_cdev);
512 struct lp5521_chip *chip = led_to_lp5521(led);
516 if (strict_strtoul(buf, 0, &curr))
519 if (curr > led->max_current)
522 mutex_lock(&chip->lock);
523 ret = lp5521_set_led_current(chip, led->id, curr);
524 mutex_unlock(&chip->lock);
529 led->led_current = (u8)curr;
534 static ssize_t lp5521_selftest(struct device *dev,
535 struct device_attribute *attr,
538 struct i2c_client *client = to_i2c_client(dev);
539 struct lp5521_chip *chip = i2c_get_clientdata(client);
542 mutex_lock(&chip->lock);
543 ret = lp5521_run_selftest(chip, buf);
544 mutex_unlock(&chip->lock);
545 return sprintf(buf, "%s\n", ret ? "FAIL" : "OK");
548 /* led class device attributes */
549 static DEVICE_ATTR(led_current, S_IRUGO | S_IWUGO, show_current, store_current);
550 static DEVICE_ATTR(max_current, S_IRUGO , show_max_current, NULL);
552 static struct attribute *lp5521_led_attributes[] = {
553 &dev_attr_led_current.attr,
554 &dev_attr_max_current.attr,
558 static struct attribute_group lp5521_led_attribute_group = {
559 .attrs = lp5521_led_attributes
562 /* device attributes */
563 static DEVICE_ATTR(engine1_mode, S_IRUGO | S_IWUGO,
564 show_engine1_mode, store_engine1_mode);
565 static DEVICE_ATTR(engine2_mode, S_IRUGO | S_IWUGO,
566 show_engine2_mode, store_engine2_mode);
567 static DEVICE_ATTR(engine3_mode, S_IRUGO | S_IWUGO,
568 show_engine3_mode, store_engine3_mode);
569 static DEVICE_ATTR(engine1_load, S_IWUGO, NULL, store_engine1_load);
570 static DEVICE_ATTR(engine2_load, S_IWUGO, NULL, store_engine2_load);
571 static DEVICE_ATTR(engine3_load, S_IWUGO, NULL, store_engine3_load);
572 static DEVICE_ATTR(selftest, S_IRUGO, lp5521_selftest, NULL);
574 static struct attribute *lp5521_attributes[] = {
575 &dev_attr_engine1_mode.attr,
576 &dev_attr_engine2_mode.attr,
577 &dev_attr_engine3_mode.attr,
578 &dev_attr_selftest.attr,
582 static struct attribute *lp5521_engine1_attributes[] = {
583 &dev_attr_engine1_load.attr,
587 static struct attribute *lp5521_engine2_attributes[] = {
588 &dev_attr_engine2_load.attr,
592 static struct attribute *lp5521_engine3_attributes[] = {
593 &dev_attr_engine3_load.attr,
597 static const struct attribute_group lp5521_group = {
598 .attrs = lp5521_attributes,
601 static const struct attribute_group lp5521_engine_group[] = {
602 {.attrs = lp5521_engine1_attributes },
603 {.attrs = lp5521_engine2_attributes },
604 {.attrs = lp5521_engine3_attributes },
607 static int lp5521_register_sysfs(struct i2c_client *client)
609 struct device *dev = &client->dev;
610 return sysfs_create_group(&dev->kobj, &lp5521_group);
613 static void lp5521_unregister_sysfs(struct i2c_client *client)
615 struct lp5521_chip *chip = i2c_get_clientdata(client);
616 struct device *dev = &client->dev;
619 sysfs_remove_group(&dev->kobj, &lp5521_group);
621 for (i = 0; i < ARRAY_SIZE(chip->engines); i++) {
622 if (chip->engines[i].mode == LP5521_CMD_LOAD)
623 sysfs_remove_group(&dev->kobj,
624 chip->engines[i].attributes);
627 for (i = 0; i < chip->num_leds; i++)
628 sysfs_remove_group(&chip->leds[i].cdev.dev->kobj,
629 &lp5521_led_attribute_group);
632 static int __init lp5521_init_led(struct lp5521_led *led,
633 struct i2c_client *client,
634 int chan, struct lp5521_platform_data *pdata)
636 struct device *dev = &client->dev;
640 if (chan >= LP5521_MAX_LEDS)
643 if (pdata->led_config[chan].led_current == 0)
646 led->led_current = pdata->led_config[chan].led_current;
647 led->max_current = pdata->led_config[chan].max_current;
648 led->chan_nr = pdata->led_config[chan].chan_nr;
650 if (led->chan_nr >= LP5521_MAX_LEDS) {
651 dev_err(dev, "Use channel numbers between 0 and %d\n",
652 LP5521_MAX_LEDS - 1);
656 snprintf(name, sizeof(name), "%s:channel%d", client->name, chan);
657 led->cdev.brightness_set = lp5521_set_brightness;
658 led->cdev.name = name;
659 res = led_classdev_register(dev, &led->cdev);
661 dev_err(dev, "couldn't register led on channel %d\n", chan);
665 res = sysfs_create_group(&led->cdev.dev->kobj,
666 &lp5521_led_attribute_group);
668 dev_err(dev, "couldn't register current attribute\n");
669 led_classdev_unregister(&led->cdev);
675 static int lp5521_probe(struct i2c_client *client,
676 const struct i2c_device_id *id)
678 struct lp5521_chip *chip;
679 struct lp5521_platform_data *pdata;
682 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
686 i2c_set_clientdata(client, chip);
687 chip->client = client;
689 pdata = client->dev.platform_data;
692 dev_err(&client->dev, "no platform data\n");
697 mutex_init(&chip->lock);
701 if (pdata->setup_resources) {
702 ret = pdata->setup_resources();
709 usleep_range(1000, 2000); /* Keep enable down at least 1ms */
711 usleep_range(1000, 2000); /* 500us abs min. */
714 lp5521_write(client, LP5521_REG_RESET, 0xff);
715 usleep_range(10000, 20000); /*
716 * Exact value is not available. 10 - 20ms
717 * appears to be enough for reset.
719 ret = lp5521_detect(client);
722 dev_err(&client->dev, "Chip not found\n");
726 dev_info(&client->dev, "%s programmable led chip found\n", id->name);
728 ret = lp5521_configure(client, lp5521_engine_group);
730 dev_err(&client->dev, "error configuring chip\n");
734 /* Initialize leds */
735 chip->num_channels = pdata->num_channels;
738 for (i = 0; i < pdata->num_channels; i++) {
739 /* Do not initialize channels that are not connected */
740 if (pdata->led_config[i].led_current == 0)
743 ret = lp5521_init_led(&chip->leds[led], client, i, pdata);
745 dev_err(&client->dev, "error initializing leds\n");
750 chip->leds[led].id = led;
751 /* Set initial LED current */
752 lp5521_set_led_current(chip, led,
753 chip->leds[led].led_current);
755 INIT_WORK(&(chip->leds[led].brightness_work),
756 lp5521_led_brightness_work);
761 ret = lp5521_register_sysfs(client);
763 dev_err(&client->dev, "registering sysfs failed\n");
768 for (i = 0; i < chip->num_leds; i++) {
769 led_classdev_unregister(&chip->leds[i].cdev);
770 cancel_work_sync(&chip->leds[i].brightness_work);
775 if (pdata->release_resources)
776 pdata->release_resources();
782 static int lp5521_remove(struct i2c_client *client)
784 struct lp5521_chip *chip = i2c_get_clientdata(client);
787 lp5521_unregister_sysfs(client);
789 for (i = 0; i < chip->num_leds; i++) {
790 led_classdev_unregister(&chip->leds[i].cdev);
791 cancel_work_sync(&chip->leds[i].brightness_work);
794 if (chip->pdata->enable)
795 chip->pdata->enable(0);
796 if (chip->pdata->release_resources)
797 chip->pdata->release_resources();
802 static const struct i2c_device_id lp5521_id[] = {
803 { "lp5521", 0 }, /* Three channel chip */
806 MODULE_DEVICE_TABLE(i2c, lp5521_id);
808 static struct i2c_driver lp5521_driver = {
812 .probe = lp5521_probe,
813 .remove = lp5521_remove,
814 .id_table = lp5521_id,
817 static int __init lp5521_init(void)
821 ret = i2c_add_driver(&lp5521_driver);
824 printk(KERN_ALERT "Adding lp5521 driver failed\n");
829 static void __exit lp5521_exit(void)
831 i2c_del_driver(&lp5521_driver);
834 module_init(lp5521_init);
835 module_exit(lp5521_exit);
837 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
838 MODULE_DESCRIPTION("LP5521 LED engine");
839 MODULE_LICENSE("GPL v2");