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/init.h>
29 #include <linux/leds.h>
30 #include <linux/module.h>
31 #include <linux/mutex.h>
32 #include <linux/platform_data/leds-lp55xx.h>
33 #include <linux/slab.h>
36 #include "leds-lp55xx-common.h"
38 #define LP5521_PROGRAM_LENGTH 32
39 #define LP5521_MAX_LEDS 3
40 #define LP5521_CMD_DIRECT 0x3F
43 #define LP5521_REG_ENABLE 0x00
44 #define LP5521_REG_OP_MODE 0x01
45 #define LP5521_REG_R_PWM 0x02
46 #define LP5521_REG_G_PWM 0x03
47 #define LP5521_REG_B_PWM 0x04
48 #define LP5521_REG_R_CURRENT 0x05
49 #define LP5521_REG_G_CURRENT 0x06
50 #define LP5521_REG_B_CURRENT 0x07
51 #define LP5521_REG_CONFIG 0x08
52 #define LP5521_REG_STATUS 0x0C
53 #define LP5521_REG_RESET 0x0D
54 #define LP5521_REG_R_PROG_MEM 0x10
55 #define LP5521_REG_G_PROG_MEM 0x30
56 #define LP5521_REG_B_PROG_MEM 0x50
58 /* Base register to set LED current */
59 #define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT
60 /* Base register to set the brightness */
61 #define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM
63 /* Bits in ENABLE register */
64 #define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */
65 #define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */
66 #define LP5521_EXEC_RUN 0x2A
67 #define LP5521_ENABLE_DEFAULT \
68 (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
69 #define LP5521_ENABLE_RUN_PROGRAM \
70 (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)
73 #define LP5521_PWM_HF 0x40 /* PWM: 0 = 256Hz, 1 = 558Hz */
74 #define LP5521_PWRSAVE_EN 0x20 /* 1 = Power save mode */
75 #define LP5521_CP_MODE_OFF 0 /* Charge pump (CP) off */
76 #define LP5521_CP_MODE_BYPASS 8 /* CP forced to bypass mode */
77 #define LP5521_CP_MODE_1X5 0x10 /* CP forced to 1.5x mode */
78 #define LP5521_CP_MODE_AUTO 0x18 /* Automatic mode selection */
79 #define LP5521_R_TO_BATT 0x04 /* R out: 0 = CP, 1 = Vbat */
80 #define LP5521_CLK_INT 0x01 /* Internal clock */
81 #define LP5521_DEFAULT_CFG \
82 (LP5521_PWM_HF | LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO)
85 #define LP5521_EXT_CLK_USED 0x08
87 /* default R channel current register value */
88 #define LP5521_REG_R_CURR_DEFAULT 0xAF
90 /* Reset register value */
91 #define LP5521_RESET 0xFF
93 /* Program Memory Operations */
94 #define LP5521_MODE_R_M 0x30 /* Operation Mode Register */
95 #define LP5521_MODE_G_M 0x0C
96 #define LP5521_MODE_B_M 0x03
97 #define LP5521_LOAD_R 0x10
98 #define LP5521_LOAD_G 0x04
99 #define LP5521_LOAD_B 0x01
101 #define LP5521_R_IS_LOADING(mode) \
102 ((mode & LP5521_MODE_R_M) == LP5521_LOAD_R)
103 #define LP5521_G_IS_LOADING(mode) \
104 ((mode & LP5521_MODE_G_M) == LP5521_LOAD_G)
105 #define LP5521_B_IS_LOADING(mode) \
106 ((mode & LP5521_MODE_B_M) == LP5521_LOAD_B)
108 #define LP5521_EXEC_R_M 0x30 /* Enable Register */
109 #define LP5521_EXEC_G_M 0x0C
110 #define LP5521_EXEC_B_M 0x03
111 #define LP5521_EXEC_M 0x3F
112 #define LP5521_RUN_R 0x20
113 #define LP5521_RUN_G 0x08
114 #define LP5521_RUN_B 0x02
116 static inline void lp5521_wait_opmode_done(void)
118 /* operation mode change needs to be longer than 153 us */
119 usleep_range(200, 300);
122 static inline void lp5521_wait_enable_done(void)
124 /* it takes more 488 us to update ENABLE register */
125 usleep_range(500, 600);
128 static void lp5521_set_led_current(struct lp55xx_led
*led
, u8 led_current
)
130 led
->led_current
= led_current
;
131 lp55xx_write(led
->chip
, LP5521_REG_LED_CURRENT_BASE
+ led
->chan_nr
,
135 static void lp5521_load_engine(struct lp55xx_chip
*chip
)
137 enum lp55xx_engine_index idx
= chip
->engine_idx
;
139 [LP55XX_ENGINE_1
] = LP5521_MODE_R_M
,
140 [LP55XX_ENGINE_2
] = LP5521_MODE_G_M
,
141 [LP55XX_ENGINE_3
] = LP5521_MODE_B_M
,
145 [LP55XX_ENGINE_1
] = LP5521_LOAD_R
,
146 [LP55XX_ENGINE_2
] = LP5521_LOAD_G
,
147 [LP55XX_ENGINE_3
] = LP5521_LOAD_B
,
150 lp55xx_update_bits(chip
, LP5521_REG_OP_MODE
, mask
[idx
], val
[idx
]);
152 lp5521_wait_opmode_done();
155 static void lp5521_stop_engine(struct lp55xx_chip
*chip
)
157 lp55xx_write(chip
, LP5521_REG_OP_MODE
, 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};
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 mutex_lock(&chip
->lock
);
249 for (i
= 0; i
< LP5521_PROGRAM_LENGTH
; i
++) {
250 ret
= lp55xx_write(chip
, addr
[idx
] + i
, pattern
[i
]);
252 mutex_unlock(&chip
->lock
);
257 mutex_unlock(&chip
->lock
);
262 dev_err(&chip
->cl
->dev
, "wrong pattern format\n");
266 static void lp5521_firmware_loaded(struct lp55xx_chip
*chip
)
268 const struct firmware
*fw
= chip
->fw
;
270 if (fw
->size
> LP5521_PROGRAM_LENGTH
) {
271 dev_err(&chip
->cl
->dev
, "firmware data size overflow: %zu\n",
277 * Program momery sequence
278 * 1) set engine mode to "LOAD"
279 * 2) write firmware data into program memory
282 lp5521_load_engine(chip
);
283 lp5521_update_program_memory(chip
, fw
->data
, fw
->size
);
286 static int lp5521_post_init_device(struct lp55xx_chip
*chip
)
292 * Make sure that the chip is reset by reading back the r channel
293 * current reg. This is dummy read is required on some platforms -
294 * otherwise further access to the R G B channels in the
295 * LP5521_REG_ENABLE register will not have any effect - strange!
297 ret
= lp55xx_read(chip
, LP5521_REG_R_CURRENT
, &val
);
299 dev_err(&chip
->cl
->dev
, "error in resetting chip\n");
302 if (val
!= LP5521_REG_R_CURR_DEFAULT
) {
303 dev_err(&chip
->cl
->dev
,
304 "unexpected data in register (expected 0x%x got 0x%x)\n",
305 LP5521_REG_R_CURR_DEFAULT
, val
);
309 usleep_range(10000, 20000);
311 /* Set all PWMs to direct control mode */
312 ret
= lp55xx_write(chip
, LP5521_REG_OP_MODE
, LP5521_CMD_DIRECT
);
314 /* Update configuration for the clock setting */
315 val
= LP5521_DEFAULT_CFG
;
316 if (!lp55xx_is_extclk_used(chip
))
317 val
|= LP5521_CLK_INT
;
319 ret
= lp55xx_write(chip
, LP5521_REG_CONFIG
, val
);
323 /* Initialize all channels PWM to zero -> leds off */
324 lp55xx_write(chip
, LP5521_REG_R_PWM
, 0);
325 lp55xx_write(chip
, LP5521_REG_G_PWM
, 0);
326 lp55xx_write(chip
, LP5521_REG_B_PWM
, 0);
328 /* Set engines are set to run state when OP_MODE enables engines */
329 ret
= lp55xx_write(chip
, LP5521_REG_ENABLE
, LP5521_ENABLE_RUN_PROGRAM
);
333 lp5521_wait_enable_done();
338 static int lp5521_run_selftest(struct lp55xx_chip
*chip
, char *buf
)
340 struct lp55xx_platform_data
*pdata
= chip
->pdata
;
344 ret
= lp55xx_read(chip
, LP5521_REG_STATUS
, &status
);
348 if (pdata
->clock_mode
!= LP55XX_CLOCK_EXT
)
351 /* Check that ext clock is really in use if requested */
352 if ((status
& LP5521_EXT_CLK_USED
) == 0)
358 static void lp5521_led_brightness_work(struct work_struct
*work
)
360 struct lp55xx_led
*led
= container_of(work
, struct lp55xx_led
,
362 struct lp55xx_chip
*chip
= led
->chip
;
364 mutex_lock(&chip
->lock
);
365 lp55xx_write(chip
, LP5521_REG_LED_PWM_BASE
+ led
->chan_nr
,
367 mutex_unlock(&chip
->lock
);
370 static ssize_t
show_engine_mode(struct device
*dev
,
371 struct device_attribute
*attr
,
374 struct lp55xx_led
*led
= i2c_get_clientdata(to_i2c_client(dev
));
375 struct lp55xx_chip
*chip
= led
->chip
;
376 enum lp55xx_engine_mode mode
= chip
->engines
[nr
- 1].mode
;
379 case LP55XX_ENGINE_RUN
:
380 return sprintf(buf
, "run\n");
381 case LP55XX_ENGINE_LOAD
:
382 return sprintf(buf
, "load\n");
383 case LP55XX_ENGINE_DISABLED
:
385 return sprintf(buf
, "disabled\n");
392 static ssize_t
store_engine_mode(struct device
*dev
,
393 struct device_attribute
*attr
,
394 const char *buf
, size_t len
, int nr
)
396 struct lp55xx_led
*led
= i2c_get_clientdata(to_i2c_client(dev
));
397 struct lp55xx_chip
*chip
= led
->chip
;
398 struct lp55xx_engine
*engine
= &chip
->engines
[nr
- 1];
400 mutex_lock(&chip
->lock
);
402 chip
->engine_idx
= nr
;
404 if (!strncmp(buf
, "run", 3)) {
405 lp5521_run_engine(chip
, true);
406 engine
->mode
= LP55XX_ENGINE_RUN
;
407 } else if (!strncmp(buf
, "load", 4)) {
408 lp5521_stop_engine(chip
);
409 lp5521_load_engine(chip
);
410 engine
->mode
= LP55XX_ENGINE_LOAD
;
411 } else if (!strncmp(buf
, "disabled", 8)) {
412 lp5521_stop_engine(chip
);
413 engine
->mode
= LP55XX_ENGINE_DISABLED
;
416 mutex_unlock(&chip
->lock
);
424 static ssize_t
store_engine_load(struct device
*dev
,
425 struct device_attribute
*attr
,
426 const char *buf
, size_t len
, int nr
)
428 struct lp55xx_led
*led
= i2c_get_clientdata(to_i2c_client(dev
));
429 struct lp55xx_chip
*chip
= led
->chip
;
431 mutex_lock(&chip
->lock
);
433 chip
->engine_idx
= nr
;
434 lp5521_load_engine(chip
);
436 mutex_unlock(&chip
->lock
);
438 return lp5521_update_program_memory(chip
, buf
, len
);
444 static ssize_t
lp5521_selftest(struct device
*dev
,
445 struct device_attribute
*attr
,
448 struct lp55xx_led
*led
= i2c_get_clientdata(to_i2c_client(dev
));
449 struct lp55xx_chip
*chip
= led
->chip
;
452 mutex_lock(&chip
->lock
);
453 ret
= lp5521_run_selftest(chip
, buf
);
454 mutex_unlock(&chip
->lock
);
456 return scnprintf(buf
, PAGE_SIZE
, "%s\n", ret
? "FAIL" : "OK");
459 /* device attributes */
460 static LP55XX_DEV_ATTR_RW(engine1_mode
, show_engine1_mode
, store_engine1_mode
);
461 static LP55XX_DEV_ATTR_RW(engine2_mode
, show_engine2_mode
, store_engine2_mode
);
462 static LP55XX_DEV_ATTR_RW(engine3_mode
, show_engine3_mode
, store_engine3_mode
);
463 static LP55XX_DEV_ATTR_WO(engine1_load
, store_engine1_load
);
464 static LP55XX_DEV_ATTR_WO(engine2_load
, store_engine2_load
);
465 static LP55XX_DEV_ATTR_WO(engine3_load
, store_engine3_load
);
466 static LP55XX_DEV_ATTR_RO(selftest
, lp5521_selftest
);
468 static struct attribute
*lp5521_attributes
[] = {
469 &dev_attr_engine1_mode
.attr
,
470 &dev_attr_engine2_mode
.attr
,
471 &dev_attr_engine3_mode
.attr
,
472 &dev_attr_engine1_load
.attr
,
473 &dev_attr_engine2_load
.attr
,
474 &dev_attr_engine3_load
.attr
,
475 &dev_attr_selftest
.attr
,
479 static const struct attribute_group lp5521_group
= {
480 .attrs
= lp5521_attributes
,
483 /* Chip specific configurations */
484 static struct lp55xx_device_config lp5521_cfg
= {
486 .addr
= LP5521_REG_RESET
,
490 .addr
= LP5521_REG_ENABLE
,
491 .val
= LP5521_ENABLE_DEFAULT
,
493 .max_channel
= LP5521_MAX_LEDS
,
494 .post_init_device
= lp5521_post_init_device
,
495 .brightness_work_fn
= lp5521_led_brightness_work
,
496 .set_led_current
= lp5521_set_led_current
,
497 .firmware_cb
= lp5521_firmware_loaded
,
498 .run_engine
= lp5521_run_engine
,
499 .dev_attr_group
= &lp5521_group
,
502 static int lp5521_probe(struct i2c_client
*client
,
503 const struct i2c_device_id
*id
)
506 struct lp55xx_chip
*chip
;
507 struct lp55xx_led
*led
;
508 struct lp55xx_platform_data
*pdata
;
509 struct device_node
*np
= client
->dev
.of_node
;
511 if (!dev_get_platdata(&client
->dev
)) {
513 ret
= lp55xx_of_populate_pdata(&client
->dev
, np
);
517 dev_err(&client
->dev
, "no platform data\n");
521 pdata
= dev_get_platdata(&client
->dev
);
523 chip
= devm_kzalloc(&client
->dev
, sizeof(*chip
), GFP_KERNEL
);
527 led
= devm_kzalloc(&client
->dev
,
528 sizeof(*led
) * pdata
->num_channels
, GFP_KERNEL
);
534 chip
->cfg
= &lp5521_cfg
;
536 mutex_init(&chip
->lock
);
538 i2c_set_clientdata(client
, led
);
540 ret
= lp55xx_init_device(chip
);
544 dev_info(&client
->dev
, "%s programmable led chip found\n", id
->name
);
546 ret
= lp55xx_register_leds(led
, chip
);
548 goto err_register_leds
;
550 ret
= lp55xx_register_sysfs(chip
);
552 dev_err(&client
->dev
, "registering sysfs failed\n");
553 goto err_register_sysfs
;
559 lp55xx_unregister_leds(led
, chip
);
561 lp55xx_deinit_device(chip
);
566 static int lp5521_remove(struct i2c_client
*client
)
568 struct lp55xx_led
*led
= i2c_get_clientdata(client
);
569 struct lp55xx_chip
*chip
= led
->chip
;
571 lp5521_stop_engine(chip
);
572 lp55xx_unregister_sysfs(chip
);
573 lp55xx_unregister_leds(led
, chip
);
574 lp55xx_deinit_device(chip
);
579 static const struct i2c_device_id lp5521_id
[] = {
580 { "lp5521", 0 }, /* Three channel chip */
583 MODULE_DEVICE_TABLE(i2c
, lp5521_id
);
586 static const struct of_device_id of_lp5521_leds_match
[] = {
587 { .compatible
= "national,lp5521", },
591 MODULE_DEVICE_TABLE(of
, of_lp5521_leds_match
);
593 static struct i2c_driver lp5521_driver
= {
596 .of_match_table
= of_match_ptr(of_lp5521_leds_match
),
598 .probe
= lp5521_probe
,
599 .remove
= lp5521_remove
,
600 .id_table
= lp5521_id
,
603 module_i2c_driver(lp5521_driver
);
605 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
606 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
607 MODULE_DESCRIPTION("LP5521 LED engine");
608 MODULE_LICENSE("GPL v2");