1 // SPDX-License-Identifier: GPL-2.0-only
3 * LP5521 LED chip driver.
5 * Copyright (C) 2010 Nokia Corporation
6 * Copyright (C) 2012 Texas Instruments
8 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
9 * Milo(Woogyom) Kim <milo.kim@ti.com>
12 #include <linux/delay.h>
13 #include <linux/firmware.h>
14 #include <linux/i2c.h>
15 #include <linux/leds.h>
16 #include <linux/module.h>
17 #include <linux/mutex.h>
18 #include <linux/platform_data/leds-lp55xx.h>
19 #include <linux/slab.h>
22 #include "leds-lp55xx-common.h"
24 #define LP5521_PROGRAM_LENGTH 32
25 #define LP5521_MAX_LEDS 3
26 #define LP5521_CMD_DIRECT 0x3F
29 #define LP5521_REG_ENABLE 0x00
30 #define LP5521_REG_OP_MODE 0x01
31 #define LP5521_REG_R_PWM 0x02
32 #define LP5521_REG_G_PWM 0x03
33 #define LP5521_REG_B_PWM 0x04
34 #define LP5521_REG_R_CURRENT 0x05
35 #define LP5521_REG_G_CURRENT 0x06
36 #define LP5521_REG_B_CURRENT 0x07
37 #define LP5521_REG_CONFIG 0x08
38 #define LP5521_REG_STATUS 0x0C
39 #define LP5521_REG_RESET 0x0D
40 #define LP5521_REG_R_PROG_MEM 0x10
41 #define LP5521_REG_G_PROG_MEM 0x30
42 #define LP5521_REG_B_PROG_MEM 0x50
44 /* Base register to set LED current */
45 #define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT
46 /* Base register to set the brightness */
47 #define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM
49 /* Bits in ENABLE register */
50 #define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */
51 #define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */
52 #define LP5521_EXEC_RUN 0x2A
53 #define LP5521_ENABLE_DEFAULT \
54 (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
55 #define LP5521_ENABLE_RUN_PROGRAM \
56 (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)
59 #define LP5521_PWM_HF 0x40 /* PWM: 0 = 256Hz, 1 = 558Hz */
60 #define LP5521_PWRSAVE_EN 0x20 /* 1 = Power save mode */
61 #define LP5521_CP_MODE_OFF 0 /* Charge pump (CP) off */
62 #define LP5521_CP_MODE_BYPASS 8 /* CP forced to bypass mode */
63 #define LP5521_CP_MODE_1X5 0x10 /* CP forced to 1.5x mode */
64 #define LP5521_CP_MODE_AUTO 0x18 /* Automatic mode selection */
65 #define LP5521_R_TO_BATT 0x04 /* R out: 0 = CP, 1 = Vbat */
66 #define LP5521_CLK_INT 0x01 /* Internal clock */
67 #define LP5521_DEFAULT_CFG \
68 (LP5521_PWM_HF | LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO)
71 #define LP5521_EXT_CLK_USED 0x08
73 /* default R channel current register value */
74 #define LP5521_REG_R_CURR_DEFAULT 0xAF
76 /* Reset register value */
77 #define LP5521_RESET 0xFF
79 /* Program Memory Operations */
80 #define LP5521_MODE_R_M 0x30 /* Operation Mode Register */
81 #define LP5521_MODE_G_M 0x0C
82 #define LP5521_MODE_B_M 0x03
83 #define LP5521_LOAD_R 0x10
84 #define LP5521_LOAD_G 0x04
85 #define LP5521_LOAD_B 0x01
87 #define LP5521_R_IS_LOADING(mode) \
88 ((mode & LP5521_MODE_R_M) == LP5521_LOAD_R)
89 #define LP5521_G_IS_LOADING(mode) \
90 ((mode & LP5521_MODE_G_M) == LP5521_LOAD_G)
91 #define LP5521_B_IS_LOADING(mode) \
92 ((mode & LP5521_MODE_B_M) == LP5521_LOAD_B)
94 #define LP5521_EXEC_R_M 0x30 /* Enable Register */
95 #define LP5521_EXEC_G_M 0x0C
96 #define LP5521_EXEC_B_M 0x03
97 #define LP5521_EXEC_M 0x3F
98 #define LP5521_RUN_R 0x20
99 #define LP5521_RUN_G 0x08
100 #define LP5521_RUN_B 0x02
102 static inline void lp5521_wait_opmode_done(void)
104 /* operation mode change needs to be longer than 153 us */
105 usleep_range(200, 300);
108 static inline void lp5521_wait_enable_done(void)
110 /* it takes more 488 us to update ENABLE register */
111 usleep_range(500, 600);
114 static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current)
116 led->led_current = led_current;
117 lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr,
121 static void lp5521_load_engine(struct lp55xx_chip *chip)
123 enum lp55xx_engine_index idx = chip->engine_idx;
124 static const u8 mask[] = {
125 [LP55XX_ENGINE_1] = LP5521_MODE_R_M,
126 [LP55XX_ENGINE_2] = LP5521_MODE_G_M,
127 [LP55XX_ENGINE_3] = LP5521_MODE_B_M,
130 static const u8 val[] = {
131 [LP55XX_ENGINE_1] = LP5521_LOAD_R,
132 [LP55XX_ENGINE_2] = LP5521_LOAD_G,
133 [LP55XX_ENGINE_3] = LP5521_LOAD_B,
136 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]);
138 lp5521_wait_opmode_done();
141 static void lp5521_stop_all_engines(struct lp55xx_chip *chip)
143 lp55xx_write(chip, LP5521_REG_OP_MODE, 0);
144 lp5521_wait_opmode_done();
147 static void lp5521_stop_engine(struct lp55xx_chip *chip)
149 enum lp55xx_engine_index idx = chip->engine_idx;
150 static const u8 mask[] = {
151 [LP55XX_ENGINE_1] = LP5521_MODE_R_M,
152 [LP55XX_ENGINE_2] = LP5521_MODE_G_M,
153 [LP55XX_ENGINE_3] = LP5521_MODE_B_M,
156 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], 0);
158 lp5521_wait_opmode_done();
161 static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
169 lp5521_stop_engine(chip);
170 lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
171 lp5521_wait_opmode_done();
177 * operation mode and enable register should updated at the same time
180 ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode);
184 ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec);
188 /* change operation mode to RUN only when each engine is loading */
189 if (LP5521_R_IS_LOADING(mode)) {
190 mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R;
191 exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R;
194 if (LP5521_G_IS_LOADING(mode)) {
195 mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G;
196 exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G;
199 if (LP5521_B_IS_LOADING(mode)) {
200 mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B;
201 exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B;
204 lp55xx_write(chip, LP5521_REG_OP_MODE, mode);
205 lp5521_wait_opmode_done();
207 lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec);
208 lp5521_wait_enable_done();
211 static int lp5521_update_program_memory(struct lp55xx_chip *chip,
212 const u8 *data, size_t size)
214 enum lp55xx_engine_index idx = chip->engine_idx;
215 u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
216 static const u8 addr[] = {
217 [LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM,
218 [LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM,
219 [LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM,
228 while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) {
229 /* separate sscanfs because length is working only for %s */
230 ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
234 ret = sscanf(c, "%2x", &cmd);
238 pattern[i] = (u8)cmd;
243 /* Each instruction is 16bit long. Check that length is even */
247 for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) {
248 ret = lp55xx_write(chip, addr[idx] + i, pattern[i]);
256 dev_err(&chip->cl->dev, "wrong pattern format\n");
260 static void lp5521_firmware_loaded(struct lp55xx_chip *chip)
262 const struct firmware *fw = chip->fw;
264 if (fw->size > LP5521_PROGRAM_LENGTH) {
265 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
271 * Program memory sequence
272 * 1) set engine mode to "LOAD"
273 * 2) write firmware data into program memory
276 lp5521_load_engine(chip);
277 lp5521_update_program_memory(chip, fw->data, fw->size);
280 static int lp5521_post_init_device(struct lp55xx_chip *chip)
286 * Make sure that the chip is reset by reading back the r channel
287 * current reg. This is dummy read is required on some platforms -
288 * otherwise further access to the R G B channels in the
289 * LP5521_REG_ENABLE register will not have any effect - strange!
291 ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
293 dev_err(&chip->cl->dev, "error in resetting chip\n");
296 if (val != LP5521_REG_R_CURR_DEFAULT) {
297 dev_err(&chip->cl->dev,
298 "unexpected data in register (expected 0x%x got 0x%x)\n",
299 LP5521_REG_R_CURR_DEFAULT, val);
303 usleep_range(10000, 20000);
305 /* Set all PWMs to direct control mode */
306 ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
308 /* Update configuration for the clock setting */
309 val = LP5521_DEFAULT_CFG;
310 if (!lp55xx_is_extclk_used(chip))
311 val |= LP5521_CLK_INT;
313 ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
317 /* Initialize all channels PWM to zero -> leds off */
318 lp55xx_write(chip, LP5521_REG_R_PWM, 0);
319 lp55xx_write(chip, LP5521_REG_G_PWM, 0);
320 lp55xx_write(chip, LP5521_REG_B_PWM, 0);
322 /* Set engines are set to run state when OP_MODE enables engines */
323 ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
327 lp5521_wait_enable_done();
332 static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf)
334 struct lp55xx_platform_data *pdata = chip->pdata;
338 ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);
342 if (pdata->clock_mode != LP55XX_CLOCK_EXT)
345 /* Check that ext clock is really in use if requested */
346 if ((status & LP5521_EXT_CLK_USED) == 0)
352 static int lp5521_multicolor_brightness(struct lp55xx_led *led)
354 struct lp55xx_chip *chip = led->chip;
358 mutex_lock(&chip->lock);
359 for (i = 0; i < led->mc_cdev.num_colors; i++) {
360 ret = lp55xx_write(chip,
361 LP5521_REG_LED_PWM_BASE +
362 led->mc_cdev.subled_info[i].channel,
363 led->mc_cdev.subled_info[i].brightness);
367 mutex_unlock(&chip->lock);
371 static int lp5521_led_brightness(struct lp55xx_led *led)
373 struct lp55xx_chip *chip = led->chip;
376 mutex_lock(&chip->lock);
377 ret = lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr,
379 mutex_unlock(&chip->lock);
384 static ssize_t show_engine_mode(struct device *dev,
385 struct device_attribute *attr,
388 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
389 struct lp55xx_chip *chip = led->chip;
390 enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
393 case LP55XX_ENGINE_RUN:
394 return sprintf(buf, "run\n");
395 case LP55XX_ENGINE_LOAD:
396 return sprintf(buf, "load\n");
397 case LP55XX_ENGINE_DISABLED:
399 return sprintf(buf, "disabled\n");
406 static ssize_t store_engine_mode(struct device *dev,
407 struct device_attribute *attr,
408 const char *buf, size_t len, int nr)
410 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
411 struct lp55xx_chip *chip = led->chip;
412 struct lp55xx_engine *engine = &chip->engines[nr - 1];
414 mutex_lock(&chip->lock);
416 chip->engine_idx = nr;
418 if (!strncmp(buf, "run", 3)) {
419 lp5521_run_engine(chip, true);
420 engine->mode = LP55XX_ENGINE_RUN;
421 } else if (!strncmp(buf, "load", 4)) {
422 lp5521_stop_engine(chip);
423 lp5521_load_engine(chip);
424 engine->mode = LP55XX_ENGINE_LOAD;
425 } else if (!strncmp(buf, "disabled", 8)) {
426 lp5521_stop_engine(chip);
427 engine->mode = LP55XX_ENGINE_DISABLED;
430 mutex_unlock(&chip->lock);
438 static ssize_t store_engine_load(struct device *dev,
439 struct device_attribute *attr,
440 const char *buf, size_t len, int nr)
442 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
443 struct lp55xx_chip *chip = led->chip;
446 mutex_lock(&chip->lock);
448 chip->engine_idx = nr;
449 lp5521_load_engine(chip);
450 ret = lp5521_update_program_memory(chip, buf, len);
452 mutex_unlock(&chip->lock);
460 static ssize_t lp5521_selftest(struct device *dev,
461 struct device_attribute *attr,
464 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
465 struct lp55xx_chip *chip = led->chip;
468 mutex_lock(&chip->lock);
469 ret = lp5521_run_selftest(chip, buf);
470 mutex_unlock(&chip->lock);
472 return scnprintf(buf, PAGE_SIZE, "%s\n", ret ? "FAIL" : "OK");
475 /* device attributes */
476 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
477 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
478 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
479 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
480 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
481 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
482 static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);
484 static struct attribute *lp5521_attributes[] = {
485 &dev_attr_engine1_mode.attr,
486 &dev_attr_engine2_mode.attr,
487 &dev_attr_engine3_mode.attr,
488 &dev_attr_engine1_load.attr,
489 &dev_attr_engine2_load.attr,
490 &dev_attr_engine3_load.attr,
491 &dev_attr_selftest.attr,
495 static const struct attribute_group lp5521_group = {
496 .attrs = lp5521_attributes,
499 /* Chip specific configurations */
500 static struct lp55xx_device_config lp5521_cfg = {
502 .addr = LP5521_REG_RESET,
506 .addr = LP5521_REG_ENABLE,
507 .val = LP5521_ENABLE_DEFAULT,
509 .max_channel = LP5521_MAX_LEDS,
510 .post_init_device = lp5521_post_init_device,
511 .brightness_fn = lp5521_led_brightness,
512 .multicolor_brightness_fn = lp5521_multicolor_brightness,
513 .set_led_current = lp5521_set_led_current,
514 .firmware_cb = lp5521_firmware_loaded,
515 .run_engine = lp5521_run_engine,
516 .dev_attr_group = &lp5521_group,
519 static int lp5521_probe(struct i2c_client *client,
520 const struct i2c_device_id *id)
523 struct lp55xx_chip *chip;
524 struct lp55xx_led *led;
525 struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
526 struct device_node *np = dev_of_node(&client->dev);
528 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
532 chip->cfg = &lp5521_cfg;
536 pdata = lp55xx_of_populate_pdata(&client->dev, np,
539 return PTR_ERR(pdata);
541 dev_err(&client->dev, "no platform data\n");
546 led = devm_kcalloc(&client->dev,
547 pdata->num_channels, sizeof(*led), GFP_KERNEL);
554 mutex_init(&chip->lock);
556 i2c_set_clientdata(client, led);
558 ret = lp55xx_init_device(chip);
562 dev_info(&client->dev, "%s programmable led chip found\n", id->name);
564 ret = lp55xx_register_leds(led, chip);
568 ret = lp55xx_register_sysfs(chip);
570 dev_err(&client->dev, "registering sysfs failed\n");
577 lp55xx_deinit_device(chip);
582 static int lp5521_remove(struct i2c_client *client)
584 struct lp55xx_led *led = i2c_get_clientdata(client);
585 struct lp55xx_chip *chip = led->chip;
587 lp5521_stop_all_engines(chip);
588 lp55xx_unregister_sysfs(chip);
589 lp55xx_deinit_device(chip);
594 static const struct i2c_device_id lp5521_id[] = {
595 { "lp5521", 0 }, /* Three channel chip */
598 MODULE_DEVICE_TABLE(i2c, lp5521_id);
601 static const struct of_device_id of_lp5521_leds_match[] = {
602 { .compatible = "national,lp5521", },
606 MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);
608 static struct i2c_driver lp5521_driver = {
611 .of_match_table = of_match_ptr(of_lp5521_leds_match),
613 .probe = lp5521_probe,
614 .remove = lp5521_remove,
615 .id_table = lp5521_id,
618 module_i2c_driver(lp5521_driver);
620 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
621 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
622 MODULE_DESCRIPTION("LP5521 LED engine");
623 MODULE_LICENSE("GPL v2");