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>
37 #include <linux/platform_data/leds-lp55xx.h>
39 #include "leds-lp55xx-common.h"
41 #define LP5521_PROGRAM_LENGTH 32 /* in bytes */
43 #define LP5521_MAX_LEDS 3 /* Maximum number of LEDs */
44 #define LP5521_MAX_ENGINES 3 /* Maximum number of engines */
46 #define LP5521_ENG_MASK_BASE 0x30 /* 00110000 */
47 #define LP5521_ENG_STATUS_MASK 0x07 /* 00000111 */
49 #define LP5521_CMD_LOAD 0x15 /* 00010101 */
50 #define LP5521_CMD_RUN 0x2a /* 00101010 */
51 #define LP5521_CMD_DIRECT 0x3f /* 00111111 */
52 #define LP5521_CMD_DISABLED 0x00 /* 00000000 */
55 #define LP5521_REG_ENABLE 0x00
56 #define LP5521_REG_OP_MODE 0x01
57 #define LP5521_REG_R_PWM 0x02
58 #define LP5521_REG_G_PWM 0x03
59 #define LP5521_REG_B_PWM 0x04
60 #define LP5521_REG_R_CURRENT 0x05
61 #define LP5521_REG_G_CURRENT 0x06
62 #define LP5521_REG_B_CURRENT 0x07
63 #define LP5521_REG_CONFIG 0x08
64 #define LP5521_REG_R_CHANNEL_PC 0x09
65 #define LP5521_REG_G_CHANNEL_PC 0x0A
66 #define LP5521_REG_B_CHANNEL_PC 0x0B
67 #define LP5521_REG_STATUS 0x0C
68 #define LP5521_REG_RESET 0x0D
69 #define LP5521_REG_GPO 0x0E
70 #define LP5521_REG_R_PROG_MEM 0x10
71 #define LP5521_REG_G_PROG_MEM 0x30
72 #define LP5521_REG_B_PROG_MEM 0x50
74 #define LP5521_PROG_MEM_BASE LP5521_REG_R_PROG_MEM
75 #define LP5521_PROG_MEM_SIZE 0x20
77 /* Base register to set LED current */
78 #define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT
80 /* Base register to set the brightness */
81 #define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM
83 /* Bits in ENABLE register */
84 #define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */
85 #define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */
86 #define LP5521_EXEC_RUN 0x2A
87 #define LP5521_ENABLE_DEFAULT \
88 (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
89 #define LP5521_ENABLE_RUN_PROGRAM \
90 (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)
93 #define LP5521_EXT_CLK_USED 0x08
95 /* default R channel current register value */
96 #define LP5521_REG_R_CURR_DEFAULT 0xAF
101 /* Reset register value */
102 #define LP5521_RESET 0xFF
104 struct lp5521_engine {
116 struct led_classdev cdev;
117 struct work_struct brightness_work;
122 struct lp5521_platform_data *pdata;
123 struct mutex lock; /* Serialize control */
124 struct i2c_client *client;
125 struct lp5521_engine engines[LP5521_MAX_ENGINES];
126 struct lp5521_led leds[LP5521_MAX_LEDS];
131 static inline void lp5521_wait_enable_done(void)
133 /* it takes more 488 us to update ENABLE register */
134 usleep_range(500, 600);
137 static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current)
139 led->led_current = led_current;
140 lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr,
144 static inline struct lp5521_led *cdev_to_led(struct led_classdev *cdev)
146 return container_of(cdev, struct lp5521_led, cdev);
149 static inline struct lp5521_chip *engine_to_lp5521(struct lp5521_engine *engine)
151 return container_of(engine, struct lp5521_chip,
152 engines[engine->id - 1]);
155 static inline struct lp5521_chip *led_to_lp5521(struct lp5521_led *led)
157 return container_of(led, struct lp5521_chip,
161 static inline int lp5521_write(struct i2c_client *client, u8 reg, u8 value)
163 return i2c_smbus_write_byte_data(client, reg, value);
166 static int lp5521_read(struct i2c_client *client, u8 reg, u8 *buf)
170 ret = i2c_smbus_read_byte_data(client, reg);
178 static int lp5521_set_engine_mode(struct lp5521_engine *engine, u8 mode)
180 struct lp5521_chip *chip = engine_to_lp5521(engine);
181 struct i2c_client *client = chip->client;
185 /* Only transition between RUN and DIRECT mode are handled here */
186 if (mode == LP5521_CMD_LOAD)
189 if (mode == LP5521_CMD_DISABLED)
190 mode = LP5521_CMD_DIRECT;
192 ret = lp5521_read(client, LP5521_REG_OP_MODE, &engine_state);
196 /* set mode only for this engine */
197 engine_state &= ~(engine->engine_mask);
198 mode &= engine->engine_mask;
199 engine_state |= mode;
200 return lp5521_write(client, LP5521_REG_OP_MODE, engine_state);
203 static int lp5521_load_program(struct lp5521_engine *eng, const u8 *pattern)
205 struct lp5521_chip *chip = engine_to_lp5521(eng);
206 struct i2c_client *client = chip->client;
211 /* move current engine to direct mode and remember the state */
212 ret = lp5521_set_engine_mode(eng, LP5521_CMD_DIRECT);
216 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
217 usleep_range(1000, 2000);
218 ret = lp5521_read(client, LP5521_REG_OP_MODE, &mode);
222 /* For loading, all the engines to load mode */
223 lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
224 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
225 usleep_range(1000, 2000);
226 lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
227 /* Mode change requires min 500 us delay. 1 - 2 ms with margin */
228 usleep_range(1000, 2000);
230 addr = LP5521_PROG_MEM_BASE + eng->prog_page * LP5521_PROG_MEM_SIZE;
231 i2c_smbus_write_i2c_block_data(client,
233 LP5521_PROG_MEM_SIZE,
236 return lp5521_write(client, LP5521_REG_OP_MODE, mode);
239 static int lp5521_post_init_device(struct lp55xx_chip *chip)
245 * Make sure that the chip is reset by reading back the r channel
246 * current reg. This is dummy read is required on some platforms -
247 * otherwise further access to the R G B channels in the
248 * LP5521_REG_ENABLE register will not have any effect - strange!
250 ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
252 dev_err(&chip->cl->dev, "error in resetting chip\n");
255 if (val != LP5521_REG_R_CURR_DEFAULT) {
256 dev_err(&chip->cl->dev,
257 "unexpected data in register (expected 0x%x got 0x%x)\n",
258 LP5521_REG_R_CURR_DEFAULT, val);
262 usleep_range(10000, 20000);
264 /* Set all PWMs to direct control mode */
265 ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
267 val = chip->pdata->update_config ?
268 : (LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO | LP5521_R_TO_BATT);
269 ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
273 /* Initialize all channels PWM to zero -> leds off */
274 lp55xx_write(chip, LP5521_REG_R_PWM, 0);
275 lp55xx_write(chip, LP5521_REG_G_PWM, 0);
276 lp55xx_write(chip, LP5521_REG_B_PWM, 0);
278 /* Set engines are set to run state when OP_MODE enables engines */
279 ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
283 lp5521_wait_enable_done();
288 static int lp5521_run_selftest(struct lp5521_chip *chip, char *buf)
293 ret = lp5521_read(chip->client, LP5521_REG_STATUS, &status);
297 /* Check that ext clock is really in use if requested */
298 if (chip->pdata && chip->pdata->clock_mode == LP5521_CLOCK_EXT)
299 if ((status & LP5521_EXT_CLK_USED) == 0)
304 static void lp5521_led_brightness_work(struct work_struct *work)
306 struct lp55xx_led *led = container_of(work, struct lp55xx_led,
308 struct lp55xx_chip *chip = led->chip;
310 mutex_lock(&chip->lock);
311 lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr,
313 mutex_unlock(&chip->lock);
316 /* Set engine mode and create appropriate sysfs attributes, if required. */
317 static int lp5521_set_mode(struct lp5521_engine *engine, u8 mode)
321 /* if in that mode already do nothing, except for run */
322 if (mode == engine->mode && mode != LP5521_CMD_RUN)
325 if (mode == LP5521_CMD_RUN) {
326 ret = lp5521_set_engine_mode(engine, LP5521_CMD_RUN);
327 } else if (mode == LP5521_CMD_LOAD) {
328 lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
329 lp5521_set_engine_mode(engine, LP5521_CMD_LOAD);
330 } else if (mode == LP5521_CMD_DISABLED) {
331 lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
339 static int lp5521_do_store_load(struct lp5521_engine *engine,
340 const char *buf, size_t len)
342 struct lp5521_chip *chip = engine_to_lp5521(engine);
343 struct i2c_client *client = chip->client;
344 int ret, nrchars, offset = 0, i = 0;
347 u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
349 while ((offset < len - 1) && (i < LP5521_PROGRAM_LENGTH)) {
350 /* separate sscanfs because length is working only for %s */
351 ret = sscanf(buf + offset, "%2s%n ", c, &nrchars);
354 ret = sscanf(c, "%2x", &cmd);
357 pattern[i] = (u8)cmd;
363 /* Each instruction is 16bit long. Check that length is even */
367 mutex_lock(&chip->lock);
368 if (engine->mode == LP5521_CMD_LOAD)
369 ret = lp5521_load_program(engine, pattern);
372 mutex_unlock(&chip->lock);
375 dev_err(&client->dev, "failed loading pattern\n");
381 dev_err(&client->dev, "wrong pattern format\n");
385 static ssize_t store_engine_load(struct device *dev,
386 struct device_attribute *attr,
387 const char *buf, size_t len, int nr)
389 struct i2c_client *client = to_i2c_client(dev);
390 struct lp5521_chip *chip = i2c_get_clientdata(client);
391 return lp5521_do_store_load(&chip->engines[nr - 1], buf, len);
394 #define store_load(nr) \
395 static ssize_t store_engine##nr##_load(struct device *dev, \
396 struct device_attribute *attr, \
397 const char *buf, size_t len) \
399 return store_engine_load(dev, attr, buf, len, nr); \
405 static ssize_t show_engine_mode(struct device *dev,
406 struct device_attribute *attr,
409 struct i2c_client *client = to_i2c_client(dev);
410 struct lp5521_chip *chip = i2c_get_clientdata(client);
411 switch (chip->engines[nr - 1].mode) {
413 return sprintf(buf, "run\n");
414 case LP5521_CMD_LOAD:
415 return sprintf(buf, "load\n");
416 case LP5521_CMD_DISABLED:
417 return sprintf(buf, "disabled\n");
419 return sprintf(buf, "disabled\n");
423 #define show_mode(nr) \
424 static ssize_t show_engine##nr##_mode(struct device *dev, \
425 struct device_attribute *attr, \
428 return show_engine_mode(dev, attr, buf, nr); \
434 static ssize_t store_engine_mode(struct device *dev,
435 struct device_attribute *attr,
436 const char *buf, size_t len, int nr)
438 struct i2c_client *client = to_i2c_client(dev);
439 struct lp5521_chip *chip = i2c_get_clientdata(client);
440 struct lp5521_engine *engine = &chip->engines[nr - 1];
441 mutex_lock(&chip->lock);
443 if (!strncmp(buf, "run", 3))
444 lp5521_set_mode(engine, LP5521_CMD_RUN);
445 else if (!strncmp(buf, "load", 4))
446 lp5521_set_mode(engine, LP5521_CMD_LOAD);
447 else if (!strncmp(buf, "disabled", 8))
448 lp5521_set_mode(engine, LP5521_CMD_DISABLED);
450 mutex_unlock(&chip->lock);
454 #define store_mode(nr) \
455 static ssize_t store_engine##nr##_mode(struct device *dev, \
456 struct device_attribute *attr, \
457 const char *buf, size_t len) \
459 return store_engine_mode(dev, attr, buf, len, nr); \
465 static ssize_t lp5521_selftest(struct device *dev,
466 struct device_attribute *attr,
469 struct i2c_client *client = to_i2c_client(dev);
470 struct lp5521_chip *chip = i2c_get_clientdata(client);
473 mutex_lock(&chip->lock);
474 ret = lp5521_run_selftest(chip, buf);
475 mutex_unlock(&chip->lock);
476 return sprintf(buf, "%s\n", ret ? "FAIL" : "OK");
479 static void lp5521_clear_program_memory(struct i2c_client *cl)
483 LP5521_REG_R_PROG_MEM,
484 LP5521_REG_G_PROG_MEM,
485 LP5521_REG_B_PROG_MEM,
488 for (i = 0; i < ARRAY_SIZE(rgb_mem); i++) {
489 lp5521_write(cl, rgb_mem[i], 0);
490 lp5521_write(cl, rgb_mem[i] + 1, 0);
494 static void lp5521_write_program_memory(struct i2c_client *cl,
495 u8 base, u8 *rgb, int size)
499 if (!rgb || size <= 0)
502 for (i = 0; i < size; i++)
503 lp5521_write(cl, base + i, *(rgb + i));
505 lp5521_write(cl, base + i, 0);
506 lp5521_write(cl, base + i + 1, 0);
509 static inline struct lp5521_led_pattern *lp5521_get_pattern
510 (struct lp5521_chip *chip, u8 offset)
512 struct lp5521_led_pattern *ptn;
513 ptn = chip->pdata->patterns + (offset - 1);
517 static void lp5521_run_led_pattern(int mode, struct lp5521_chip *chip)
519 struct lp5521_led_pattern *ptn;
520 struct i2c_client *cl = chip->client;
521 int num_patterns = chip->pdata->num_patterns;
523 if (mode > num_patterns || !(chip->pdata->patterns))
526 if (mode == PATTERN_OFF) {
527 lp5521_write(cl, LP5521_REG_ENABLE, LP5521_ENABLE_DEFAULT);
528 usleep_range(1000, 2000);
529 lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
531 ptn = lp5521_get_pattern(chip, mode);
535 lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
536 usleep_range(1000, 2000);
538 lp5521_clear_program_memory(cl);
540 lp5521_write_program_memory(cl, LP5521_REG_R_PROG_MEM,
541 ptn->r, ptn->size_r);
542 lp5521_write_program_memory(cl, LP5521_REG_G_PROG_MEM,
543 ptn->g, ptn->size_g);
544 lp5521_write_program_memory(cl, LP5521_REG_B_PROG_MEM,
545 ptn->b, ptn->size_b);
547 lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_RUN);
548 usleep_range(1000, 2000);
549 lp5521_write(cl, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
553 static ssize_t store_led_pattern(struct device *dev,
554 struct device_attribute *attr,
555 const char *buf, size_t len)
557 struct lp5521_chip *chip = i2c_get_clientdata(to_i2c_client(dev));
561 ret = kstrtoul(buf, 16, &val);
565 lp5521_run_led_pattern(val, chip);
570 static struct attribute_group lp5521_led_attribute_group = {
573 /* device attributes */
574 static DEVICE_ATTR(engine1_mode, S_IRUGO | S_IWUSR,
575 show_engine1_mode, store_engine1_mode);
576 static DEVICE_ATTR(engine2_mode, S_IRUGO | S_IWUSR,
577 show_engine2_mode, store_engine2_mode);
578 static DEVICE_ATTR(engine3_mode, S_IRUGO | S_IWUSR,
579 show_engine3_mode, store_engine3_mode);
580 static DEVICE_ATTR(engine1_load, S_IWUSR, NULL, store_engine1_load);
581 static DEVICE_ATTR(engine2_load, S_IWUSR, NULL, store_engine2_load);
582 static DEVICE_ATTR(engine3_load, S_IWUSR, NULL, store_engine3_load);
583 static DEVICE_ATTR(selftest, S_IRUGO, lp5521_selftest, NULL);
584 static DEVICE_ATTR(led_pattern, S_IWUSR, NULL, store_led_pattern);
586 static struct attribute *lp5521_attributes[] = {
587 &dev_attr_engine1_mode.attr,
588 &dev_attr_engine2_mode.attr,
589 &dev_attr_engine3_mode.attr,
590 &dev_attr_selftest.attr,
591 &dev_attr_engine1_load.attr,
592 &dev_attr_engine2_load.attr,
593 &dev_attr_engine3_load.attr,
594 &dev_attr_led_pattern.attr,
598 static const struct attribute_group lp5521_group = {
599 .attrs = lp5521_attributes,
602 static int lp5521_register_sysfs(struct i2c_client *client)
604 struct device *dev = &client->dev;
605 return sysfs_create_group(&dev->kobj, &lp5521_group);
608 static void lp5521_unregister_sysfs(struct i2c_client *client)
610 struct lp5521_chip *chip = i2c_get_clientdata(client);
611 struct device *dev = &client->dev;
614 sysfs_remove_group(&dev->kobj, &lp5521_group);
616 for (i = 0; i < chip->num_leds; i++)
617 sysfs_remove_group(&chip->leds[i].cdev.dev->kobj,
618 &lp5521_led_attribute_group);
621 static void lp5521_unregister_leds(struct lp5521_chip *chip)
625 for (i = 0; i < chip->num_leds; i++) {
626 led_classdev_unregister(&chip->leds[i].cdev);
627 cancel_work_sync(&chip->leds[i].brightness_work);
631 /* Chip specific configurations */
632 static struct lp55xx_device_config lp5521_cfg = {
634 .addr = LP5521_REG_RESET,
638 .addr = LP5521_REG_ENABLE,
639 .val = LP5521_ENABLE_DEFAULT,
641 .max_channel = LP5521_MAX_LEDS,
642 .post_init_device = lp5521_post_init_device,
643 .brightness_work_fn = lp5521_led_brightness_work,
644 .set_led_current = lp5521_set_led_current,
647 static int lp5521_probe(struct i2c_client *client,
648 const struct i2c_device_id *id)
650 struct lp5521_chip *old_chip = NULL;
652 struct lp55xx_chip *chip;
653 struct lp55xx_led *led;
654 struct lp55xx_platform_data *pdata = client->dev.platform_data;
657 dev_err(&client->dev, "no platform data\n");
661 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
665 led = devm_kzalloc(&client->dev,
666 sizeof(*led) * pdata->num_channels, GFP_KERNEL);
672 chip->cfg = &lp5521_cfg;
674 mutex_init(&chip->lock);
676 i2c_set_clientdata(client, led);
678 ret = lp55xx_init_device(chip);
682 dev_info(&client->dev, "%s programmable led chip found\n", id->name);
684 ret = lp55xx_register_leds(led, chip);
686 goto err_register_leds;
688 ret = lp5521_register_sysfs(client);
690 dev_err(&client->dev, "registering sysfs failed\n");
695 lp5521_unregister_leds(old_chip);
697 lp55xx_deinit_device(chip);
702 static int lp5521_remove(struct i2c_client *client)
704 struct lp5521_chip *old_chip = i2c_get_clientdata(client);
705 struct lp55xx_led *led = i2c_get_clientdata(client);
706 struct lp55xx_chip *chip = led->chip;
708 lp5521_run_led_pattern(PATTERN_OFF, old_chip);
709 lp5521_unregister_sysfs(client);
711 lp5521_unregister_leds(old_chip);
712 lp55xx_deinit_device(chip);
717 static const struct i2c_device_id lp5521_id[] = {
718 { "lp5521", 0 }, /* Three channel chip */
721 MODULE_DEVICE_TABLE(i2c, lp5521_id);
723 static struct i2c_driver lp5521_driver = {
727 .probe = lp5521_probe,
728 .remove = lp5521_remove,
729 .id_table = lp5521_id,
732 module_i2c_driver(lp5521_driver);
734 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
735 MODULE_DESCRIPTION("LP5521 LED engine");
736 MODULE_LICENSE("GPL v2");