2 * LP5521 LED chip driver.
4 * Copyright (C) 2010 Nokia Corporation
5 * Copyright (C) 2012 Texas Instruments
7 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
8 * Milo(Woogyom) Kim <milo.kim@ti.com>
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * version 2 as published by the Free Software Foundation.
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
25 #include <linux/delay.h>
26 #include <linux/firmware.h>
27 #include <linux/i2c.h>
28 #include <linux/leds.h>
29 #include <linux/module.h>
30 #include <linux/mutex.h>
31 #include <linux/platform_data/leds-lp55xx.h>
32 #include <linux/slab.h>
35 #include "leds-lp55xx-common.h"
37 #define LP5521_PROGRAM_LENGTH 32
38 #define LP5521_MAX_LEDS 3
39 #define LP5521_CMD_DIRECT 0x3F
42 #define LP5521_REG_ENABLE 0x00
43 #define LP5521_REG_OP_MODE 0x01
44 #define LP5521_REG_R_PWM 0x02
45 #define LP5521_REG_G_PWM 0x03
46 #define LP5521_REG_B_PWM 0x04
47 #define LP5521_REG_R_CURRENT 0x05
48 #define LP5521_REG_G_CURRENT 0x06
49 #define LP5521_REG_B_CURRENT 0x07
50 #define LP5521_REG_CONFIG 0x08
51 #define LP5521_REG_STATUS 0x0C
52 #define LP5521_REG_RESET 0x0D
53 #define LP5521_REG_R_PROG_MEM 0x10
54 #define LP5521_REG_G_PROG_MEM 0x30
55 #define LP5521_REG_B_PROG_MEM 0x50
57 /* Base register to set LED current */
58 #define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT
59 /* Base register to set the brightness */
60 #define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM
62 /* Bits in ENABLE register */
63 #define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */
64 #define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */
65 #define LP5521_EXEC_RUN 0x2A
66 #define LP5521_ENABLE_DEFAULT \
67 (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
68 #define LP5521_ENABLE_RUN_PROGRAM \
69 (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)
72 #define LP5521_PWM_HF 0x40 /* PWM: 0 = 256Hz, 1 = 558Hz */
73 #define LP5521_PWRSAVE_EN 0x20 /* 1 = Power save mode */
74 #define LP5521_CP_MODE_OFF 0 /* Charge pump (CP) off */
75 #define LP5521_CP_MODE_BYPASS 8 /* CP forced to bypass mode */
76 #define LP5521_CP_MODE_1X5 0x10 /* CP forced to 1.5x mode */
77 #define LP5521_CP_MODE_AUTO 0x18 /* Automatic mode selection */
78 #define LP5521_R_TO_BATT 0x04 /* R out: 0 = CP, 1 = Vbat */
79 #define LP5521_CLK_INT 0x01 /* Internal clock */
80 #define LP5521_DEFAULT_CFG \
81 (LP5521_PWM_HF | LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO)
84 #define LP5521_EXT_CLK_USED 0x08
86 /* default R channel current register value */
87 #define LP5521_REG_R_CURR_DEFAULT 0xAF
89 /* Reset register value */
90 #define LP5521_RESET 0xFF
92 /* Program Memory Operations */
93 #define LP5521_MODE_R_M 0x30 /* Operation Mode Register */
94 #define LP5521_MODE_G_M 0x0C
95 #define LP5521_MODE_B_M 0x03
96 #define LP5521_LOAD_R 0x10
97 #define LP5521_LOAD_G 0x04
98 #define LP5521_LOAD_B 0x01
100 #define LP5521_R_IS_LOADING(mode) \
101 ((mode & LP5521_MODE_R_M) == LP5521_LOAD_R)
102 #define LP5521_G_IS_LOADING(mode) \
103 ((mode & LP5521_MODE_G_M) == LP5521_LOAD_G)
104 #define LP5521_B_IS_LOADING(mode) \
105 ((mode & LP5521_MODE_B_M) == LP5521_LOAD_B)
107 #define LP5521_EXEC_R_M 0x30 /* Enable Register */
108 #define LP5521_EXEC_G_M 0x0C
109 #define LP5521_EXEC_B_M 0x03
110 #define LP5521_EXEC_M 0x3F
111 #define LP5521_RUN_R 0x20
112 #define LP5521_RUN_G 0x08
113 #define LP5521_RUN_B 0x02
115 static inline void lp5521_wait_opmode_done(void)
117 /* operation mode change needs to be longer than 153 us */
118 usleep_range(200, 300);
121 static inline void lp5521_wait_enable_done(void)
123 /* it takes more 488 us to update ENABLE register */
124 usleep_range(500, 600);
127 static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current)
129 led->led_current = led_current;
130 lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr,
134 static void lp5521_load_engine(struct lp55xx_chip *chip)
136 enum lp55xx_engine_index idx = chip->engine_idx;
138 [LP55XX_ENGINE_1] = LP5521_MODE_R_M,
139 [LP55XX_ENGINE_2] = LP5521_MODE_G_M,
140 [LP55XX_ENGINE_3] = LP5521_MODE_B_M,
144 [LP55XX_ENGINE_1] = LP5521_LOAD_R,
145 [LP55XX_ENGINE_2] = LP5521_LOAD_G,
146 [LP55XX_ENGINE_3] = LP5521_LOAD_B,
149 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]);
151 lp5521_wait_opmode_done();
154 static void lp5521_stop_all_engines(struct lp55xx_chip *chip)
156 lp55xx_write(chip, LP5521_REG_OP_MODE, 0);
157 lp5521_wait_opmode_done();
160 static void lp5521_stop_engine(struct lp55xx_chip *chip)
162 enum lp55xx_engine_index idx = chip->engine_idx;
164 [LP55XX_ENGINE_1] = LP5521_MODE_R_M,
165 [LP55XX_ENGINE_2] = LP5521_MODE_G_M,
166 [LP55XX_ENGINE_3] = LP5521_MODE_B_M,
169 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], 0);
171 lp5521_wait_opmode_done();
174 static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
182 lp5521_stop_engine(chip);
183 lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
184 lp5521_wait_opmode_done();
190 * operation mode and enable register should updated at the same time
193 ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode);
197 ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec);
201 /* change operation mode to RUN only when each engine is loading */
202 if (LP5521_R_IS_LOADING(mode)) {
203 mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R;
204 exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R;
207 if (LP5521_G_IS_LOADING(mode)) {
208 mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G;
209 exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G;
212 if (LP5521_B_IS_LOADING(mode)) {
213 mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B;
214 exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B;
217 lp55xx_write(chip, LP5521_REG_OP_MODE, mode);
218 lp5521_wait_opmode_done();
220 lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec);
221 lp5521_wait_enable_done();
224 static int lp5521_update_program_memory(struct lp55xx_chip *chip,
225 const u8 *data, size_t size)
227 enum lp55xx_engine_index idx = chip->engine_idx;
228 u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
230 [LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM,
231 [LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM,
232 [LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM,
241 while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) {
242 /* separate sscanfs because length is working only for %s */
243 ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
247 ret = sscanf(c, "%2x", &cmd);
251 pattern[i] = (u8)cmd;
256 /* Each instruction is 16bit long. Check that length is even */
260 for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) {
261 ret = lp55xx_write(chip, addr[idx] + i, pattern[i]);
269 dev_err(&chip->cl->dev, "wrong pattern format\n");
273 static void lp5521_firmware_loaded(struct lp55xx_chip *chip)
275 const struct firmware *fw = chip->fw;
277 if (fw->size > LP5521_PROGRAM_LENGTH) {
278 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
284 * Program momery sequence
285 * 1) set engine mode to "LOAD"
286 * 2) write firmware data into program memory
289 lp5521_load_engine(chip);
290 lp5521_update_program_memory(chip, fw->data, fw->size);
293 static int lp5521_post_init_device(struct lp55xx_chip *chip)
299 * Make sure that the chip is reset by reading back the r channel
300 * current reg. This is dummy read is required on some platforms -
301 * otherwise further access to the R G B channels in the
302 * LP5521_REG_ENABLE register will not have any effect - strange!
304 ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
306 dev_err(&chip->cl->dev, "error in resetting chip\n");
309 if (val != LP5521_REG_R_CURR_DEFAULT) {
310 dev_err(&chip->cl->dev,
311 "unexpected data in register (expected 0x%x got 0x%x)\n",
312 LP5521_REG_R_CURR_DEFAULT, val);
316 usleep_range(10000, 20000);
318 /* Set all PWMs to direct control mode */
319 ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
321 /* Update configuration for the clock setting */
322 val = LP5521_DEFAULT_CFG;
323 if (!lp55xx_is_extclk_used(chip))
324 val |= LP5521_CLK_INT;
326 ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
330 /* Initialize all channels PWM to zero -> leds off */
331 lp55xx_write(chip, LP5521_REG_R_PWM, 0);
332 lp55xx_write(chip, LP5521_REG_G_PWM, 0);
333 lp55xx_write(chip, LP5521_REG_B_PWM, 0);
335 /* Set engines are set to run state when OP_MODE enables engines */
336 ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
340 lp5521_wait_enable_done();
345 static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf)
347 struct lp55xx_platform_data *pdata = chip->pdata;
351 ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);
355 if (pdata->clock_mode != LP55XX_CLOCK_EXT)
358 /* Check that ext clock is really in use if requested */
359 if ((status & LP5521_EXT_CLK_USED) == 0)
365 static void lp5521_led_brightness_work(struct work_struct *work)
367 struct lp55xx_led *led = container_of(work, struct lp55xx_led,
369 struct lp55xx_chip *chip = led->chip;
371 mutex_lock(&chip->lock);
372 lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr,
374 mutex_unlock(&chip->lock);
377 static ssize_t show_engine_mode(struct device *dev,
378 struct device_attribute *attr,
381 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
382 struct lp55xx_chip *chip = led->chip;
383 enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
386 case LP55XX_ENGINE_RUN:
387 return sprintf(buf, "run\n");
388 case LP55XX_ENGINE_LOAD:
389 return sprintf(buf, "load\n");
390 case LP55XX_ENGINE_DISABLED:
392 return sprintf(buf, "disabled\n");
399 static ssize_t store_engine_mode(struct device *dev,
400 struct device_attribute *attr,
401 const char *buf, size_t len, int nr)
403 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
404 struct lp55xx_chip *chip = led->chip;
405 struct lp55xx_engine *engine = &chip->engines[nr - 1];
407 mutex_lock(&chip->lock);
409 chip->engine_idx = nr;
411 if (!strncmp(buf, "run", 3)) {
412 lp5521_run_engine(chip, true);
413 engine->mode = LP55XX_ENGINE_RUN;
414 } else if (!strncmp(buf, "load", 4)) {
415 lp5521_stop_engine(chip);
416 lp5521_load_engine(chip);
417 engine->mode = LP55XX_ENGINE_LOAD;
418 } else if (!strncmp(buf, "disabled", 8)) {
419 lp5521_stop_engine(chip);
420 engine->mode = LP55XX_ENGINE_DISABLED;
423 mutex_unlock(&chip->lock);
431 static ssize_t store_engine_load(struct device *dev,
432 struct device_attribute *attr,
433 const char *buf, size_t len, int nr)
435 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
436 struct lp55xx_chip *chip = led->chip;
439 mutex_lock(&chip->lock);
441 chip->engine_idx = nr;
442 lp5521_load_engine(chip);
443 ret = lp5521_update_program_memory(chip, buf, len);
445 mutex_unlock(&chip->lock);
453 static ssize_t lp5521_selftest(struct device *dev,
454 struct device_attribute *attr,
457 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
458 struct lp55xx_chip *chip = led->chip;
461 mutex_lock(&chip->lock);
462 ret = lp5521_run_selftest(chip, buf);
463 mutex_unlock(&chip->lock);
465 return scnprintf(buf, PAGE_SIZE, "%s\n", ret ? "FAIL" : "OK");
468 /* device attributes */
469 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
470 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
471 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
472 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
473 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
474 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
475 static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);
477 static struct attribute *lp5521_attributes[] = {
478 &dev_attr_engine1_mode.attr,
479 &dev_attr_engine2_mode.attr,
480 &dev_attr_engine3_mode.attr,
481 &dev_attr_engine1_load.attr,
482 &dev_attr_engine2_load.attr,
483 &dev_attr_engine3_load.attr,
484 &dev_attr_selftest.attr,
488 static const struct attribute_group lp5521_group = {
489 .attrs = lp5521_attributes,
492 /* Chip specific configurations */
493 static struct lp55xx_device_config lp5521_cfg = {
495 .addr = LP5521_REG_RESET,
499 .addr = LP5521_REG_ENABLE,
500 .val = LP5521_ENABLE_DEFAULT,
502 .max_channel = LP5521_MAX_LEDS,
503 .post_init_device = lp5521_post_init_device,
504 .brightness_work_fn = lp5521_led_brightness_work,
505 .set_led_current = lp5521_set_led_current,
506 .firmware_cb = lp5521_firmware_loaded,
507 .run_engine = lp5521_run_engine,
508 .dev_attr_group = &lp5521_group,
511 static int lp5521_probe(struct i2c_client *client,
512 const struct i2c_device_id *id)
515 struct lp55xx_chip *chip;
516 struct lp55xx_led *led;
517 struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
518 struct device_node *np = client->dev.of_node;
522 pdata = lp55xx_of_populate_pdata(&client->dev, np);
524 return PTR_ERR(pdata);
526 dev_err(&client->dev, "no platform data\n");
531 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
535 led = devm_kzalloc(&client->dev,
536 sizeof(*led) * pdata->num_channels, GFP_KERNEL);
542 chip->cfg = &lp5521_cfg;
544 mutex_init(&chip->lock);
546 i2c_set_clientdata(client, led);
548 ret = lp55xx_init_device(chip);
552 dev_info(&client->dev, "%s programmable led chip found\n", id->name);
554 ret = lp55xx_register_leds(led, chip);
556 goto err_register_leds;
558 ret = lp55xx_register_sysfs(chip);
560 dev_err(&client->dev, "registering sysfs failed\n");
561 goto err_register_sysfs;
567 lp55xx_unregister_leds(led, chip);
569 lp55xx_deinit_device(chip);
574 static int lp5521_remove(struct i2c_client *client)
576 struct lp55xx_led *led = i2c_get_clientdata(client);
577 struct lp55xx_chip *chip = led->chip;
579 lp5521_stop_all_engines(chip);
580 lp55xx_unregister_sysfs(chip);
581 lp55xx_unregister_leds(led, chip);
582 lp55xx_deinit_device(chip);
587 static const struct i2c_device_id lp5521_id[] = {
588 { "lp5521", 0 }, /* Three channel chip */
591 MODULE_DEVICE_TABLE(i2c, lp5521_id);
594 static const struct of_device_id of_lp5521_leds_match[] = {
595 { .compatible = "national,lp5521", },
599 MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);
601 static struct i2c_driver lp5521_driver = {
604 .of_match_table = of_match_ptr(of_lp5521_leds_match),
606 .probe = lp5521_probe,
607 .remove = lp5521_remove,
608 .id_table = lp5521_id,
611 module_i2c_driver(lp5521_driver);
613 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
614 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
615 MODULE_DESCRIPTION("LP5521 LED engine");
616 MODULE_LICENSE("GPL v2");