1 // SPDX-License-Identifier: GPL-2.0-only
3 * Simple driver for Texas Instruments LM3630A Backlight driver chip
4 * Copyright (C) 2012 Texas Instruments
6 #include <linux/module.h>
7 #include <linux/slab.h>
9 #include <linux/backlight.h>
10 #include <linux/err.h>
11 #include <linux/delay.h>
12 #include <linux/uaccess.h>
13 #include <linux/interrupt.h>
14 #include <linux/regmap.h>
15 #include <linux/gpio/consumer.h>
16 #include <linux/pwm.h>
17 #include <linux/platform_data/lm3630a_bl.h>
20 #define REG_BOOST 0x02
21 #define REG_CONFIG 0x01
22 #define REG_BRT_A 0x03
23 #define REG_BRT_B 0x04
26 #define REG_INT_STATUS 0x09
27 #define REG_INT_EN 0x0A
28 #define REG_FAULT 0x0B
29 #define REG_PWM_OUTLOW 0x12
30 #define REG_PWM_OUTHIGH 0x13
31 #define REG_FILTER_STRENGTH 0x50
34 #define INT_DEBOUNCE_MSEC 10
36 #define LM3630A_BANK_0 0
37 #define LM3630A_BANK_1 1
39 #define LM3630A_NUM_SINKS 2
40 #define LM3630A_SINK_0 0
41 #define LM3630A_SINK_1 1
45 struct delayed_work work
;
48 struct workqueue_struct
*irqthread
;
49 struct lm3630a_platform_data
*pdata
;
50 struct backlight_device
*bleda
;
51 struct backlight_device
*bledb
;
52 struct gpio_desc
*enable_gpio
;
53 struct regmap
*regmap
;
54 struct pwm_device
*pwmd
;
58 static int lm3630a_read(struct lm3630a_chip
*pchip
, unsigned int reg
)
63 rval
= regmap_read(pchip
->regmap
, reg
, ®_val
);
66 return reg_val
& 0xFF;
69 static int lm3630a_write(struct lm3630a_chip
*pchip
,
70 unsigned int reg
, unsigned int data
)
72 return regmap_write(pchip
->regmap
, reg
, data
);
75 static int lm3630a_update(struct lm3630a_chip
*pchip
,
76 unsigned int reg
, unsigned int mask
,
79 return regmap_update_bits(pchip
->regmap
, reg
, mask
, data
);
83 static int lm3630a_chip_init(struct lm3630a_chip
*pchip
)
86 struct lm3630a_platform_data
*pdata
= pchip
->pdata
;
88 usleep_range(1000, 2000);
89 /* set Filter Strength Register */
90 rval
= lm3630a_write(pchip
, REG_FILTER_STRENGTH
, 0x03);
91 /* set Cofig. register */
92 rval
|= lm3630a_update(pchip
, REG_CONFIG
, 0x07, pdata
->pwm_ctrl
);
93 /* set boost control */
94 rval
|= lm3630a_write(pchip
, REG_BOOST
, 0x38);
96 rval
|= lm3630a_update(pchip
, REG_I_A
, 0x1F, 0x1F);
98 rval
|= lm3630a_write(pchip
, REG_I_B
, 0x1F);
100 rval
|= lm3630a_update(pchip
, REG_CTRL
, 0x14, pdata
->leda_ctrl
);
101 rval
|= lm3630a_update(pchip
, REG_CTRL
, 0x0B, pdata
->ledb_ctrl
);
102 usleep_range(1000, 2000);
103 /* set brightness A and B */
104 rval
|= lm3630a_write(pchip
, REG_BRT_A
, pdata
->leda_init_brt
);
105 rval
|= lm3630a_write(pchip
, REG_BRT_B
, pdata
->ledb_init_brt
);
108 dev_err(pchip
->dev
, "i2c failed to access register\n");
112 /* interrupt handling */
113 static void lm3630a_delayed_func(struct work_struct
*work
)
116 struct lm3630a_chip
*pchip
;
118 pchip
= container_of(work
, struct lm3630a_chip
, work
.work
);
120 rval
= lm3630a_read(pchip
, REG_INT_STATUS
);
123 "i2c failed to access REG_INT_STATUS Register\n");
127 dev_info(pchip
->dev
, "REG_INT_STATUS Register is 0x%x\n", rval
);
130 static irqreturn_t
lm3630a_isr_func(int irq
, void *chip
)
133 struct lm3630a_chip
*pchip
= chip
;
134 unsigned long delay
= msecs_to_jiffies(INT_DEBOUNCE_MSEC
);
136 queue_delayed_work(pchip
->irqthread
, &pchip
->work
, delay
);
138 rval
= lm3630a_update(pchip
, REG_CTRL
, 0x80, 0x00);
140 dev_err(pchip
->dev
, "i2c failed to access register\n");
146 static int lm3630a_intr_config(struct lm3630a_chip
*pchip
)
150 rval
= lm3630a_write(pchip
, REG_INT_EN
, 0x87);
154 INIT_DELAYED_WORK(&pchip
->work
, lm3630a_delayed_func
);
155 pchip
->irqthread
= create_singlethread_workqueue("lm3630a-irqthd");
156 if (!pchip
->irqthread
) {
157 dev_err(pchip
->dev
, "create irq thread fail\n");
160 if (request_threaded_irq
161 (pchip
->irq
, NULL
, lm3630a_isr_func
,
162 IRQF_TRIGGER_FALLING
| IRQF_ONESHOT
, "lm3630a_irq", pchip
)) {
163 dev_err(pchip
->dev
, "request threaded irq fail\n");
164 destroy_workqueue(pchip
->irqthread
);
170 static void lm3630a_pwm_ctrl(struct lm3630a_chip
*pchip
, int br
, int br_max
)
172 unsigned int period
= pchip
->pdata
->pwm_period
;
173 unsigned int duty
= br
* period
/ br_max
;
175 pwm_config(pchip
->pwmd
, duty
, period
);
177 pwm_enable(pchip
->pwmd
);
179 pwm_disable(pchip
->pwmd
);
182 /* update and get brightness */
183 static int lm3630a_bank_a_update_status(struct backlight_device
*bl
)
186 struct lm3630a_chip
*pchip
= bl_get_data(bl
);
187 enum lm3630a_pwm_ctrl pwm_ctrl
= pchip
->pdata
->pwm_ctrl
;
190 if ((pwm_ctrl
& LM3630A_PWM_BANK_A
) != 0) {
191 lm3630a_pwm_ctrl(pchip
, bl
->props
.brightness
,
192 bl
->props
.max_brightness
);
193 return bl
->props
.brightness
;
197 ret
= lm3630a_update(pchip
, REG_CTRL
, 0x80, 0x00);
200 usleep_range(1000, 2000);
201 /* minimum brightness is 0x04 */
202 ret
= lm3630a_write(pchip
, REG_BRT_A
, bl
->props
.brightness
);
203 if (bl
->props
.brightness
< 0x4)
204 ret
|= lm3630a_update(pchip
, REG_CTRL
, LM3630A_LEDA_ENABLE
, 0);
206 ret
|= lm3630a_update(pchip
, REG_CTRL
,
207 LM3630A_LEDA_ENABLE
, LM3630A_LEDA_ENABLE
);
213 dev_err(pchip
->dev
, "i2c failed to access\n");
214 return bl
->props
.brightness
;
217 static int lm3630a_bank_a_get_brightness(struct backlight_device
*bl
)
219 int brightness
, rval
;
220 struct lm3630a_chip
*pchip
= bl_get_data(bl
);
221 enum lm3630a_pwm_ctrl pwm_ctrl
= pchip
->pdata
->pwm_ctrl
;
223 if ((pwm_ctrl
& LM3630A_PWM_BANK_A
) != 0) {
224 rval
= lm3630a_read(pchip
, REG_PWM_OUTHIGH
);
227 brightness
= (rval
& 0x01) << 8;
228 rval
= lm3630a_read(pchip
, REG_PWM_OUTLOW
);
236 rval
= lm3630a_update(pchip
, REG_CTRL
, 0x80, 0x00);
239 usleep_range(1000, 2000);
240 rval
= lm3630a_read(pchip
, REG_BRT_A
);
246 bl
->props
.brightness
= brightness
;
247 return bl
->props
.brightness
;
249 dev_err(pchip
->dev
, "i2c failed to access register\n");
253 static const struct backlight_ops lm3630a_bank_a_ops
= {
254 .options
= BL_CORE_SUSPENDRESUME
,
255 .update_status
= lm3630a_bank_a_update_status
,
256 .get_brightness
= lm3630a_bank_a_get_brightness
,
259 /* update and get brightness */
260 static int lm3630a_bank_b_update_status(struct backlight_device
*bl
)
263 struct lm3630a_chip
*pchip
= bl_get_data(bl
);
264 enum lm3630a_pwm_ctrl pwm_ctrl
= pchip
->pdata
->pwm_ctrl
;
267 if ((pwm_ctrl
& LM3630A_PWM_BANK_B
) != 0) {
268 lm3630a_pwm_ctrl(pchip
, bl
->props
.brightness
,
269 bl
->props
.max_brightness
);
270 return bl
->props
.brightness
;
274 ret
= lm3630a_update(pchip
, REG_CTRL
, 0x80, 0x00);
277 usleep_range(1000, 2000);
278 /* minimum brightness is 0x04 */
279 ret
= lm3630a_write(pchip
, REG_BRT_B
, bl
->props
.brightness
);
280 if (bl
->props
.brightness
< 0x4)
281 ret
|= lm3630a_update(pchip
, REG_CTRL
, LM3630A_LEDB_ENABLE
, 0);
283 ret
|= lm3630a_update(pchip
, REG_CTRL
,
284 LM3630A_LEDB_ENABLE
, LM3630A_LEDB_ENABLE
);
290 dev_err(pchip
->dev
, "i2c failed to access REG_CTRL\n");
291 return bl
->props
.brightness
;
294 static int lm3630a_bank_b_get_brightness(struct backlight_device
*bl
)
296 int brightness
, rval
;
297 struct lm3630a_chip
*pchip
= bl_get_data(bl
);
298 enum lm3630a_pwm_ctrl pwm_ctrl
= pchip
->pdata
->pwm_ctrl
;
300 if ((pwm_ctrl
& LM3630A_PWM_BANK_B
) != 0) {
301 rval
= lm3630a_read(pchip
, REG_PWM_OUTHIGH
);
304 brightness
= (rval
& 0x01) << 8;
305 rval
= lm3630a_read(pchip
, REG_PWM_OUTLOW
);
313 rval
= lm3630a_update(pchip
, REG_CTRL
, 0x80, 0x00);
316 usleep_range(1000, 2000);
317 rval
= lm3630a_read(pchip
, REG_BRT_B
);
323 bl
->props
.brightness
= brightness
;
324 return bl
->props
.brightness
;
326 dev_err(pchip
->dev
, "i2c failed to access register\n");
330 static const struct backlight_ops lm3630a_bank_b_ops
= {
331 .options
= BL_CORE_SUSPENDRESUME
,
332 .update_status
= lm3630a_bank_b_update_status
,
333 .get_brightness
= lm3630a_bank_b_get_brightness
,
336 static int lm3630a_backlight_register(struct lm3630a_chip
*pchip
)
338 struct lm3630a_platform_data
*pdata
= pchip
->pdata
;
339 struct backlight_properties props
;
342 props
.type
= BACKLIGHT_RAW
;
343 if (pdata
->leda_ctrl
!= LM3630A_LEDA_DISABLE
) {
344 props
.brightness
= pdata
->leda_init_brt
;
345 props
.max_brightness
= pdata
->leda_max_brt
;
346 label
= pdata
->leda_label
? pdata
->leda_label
: "lm3630a_leda";
348 devm_backlight_device_register(pchip
->dev
, label
,
350 &lm3630a_bank_a_ops
, &props
);
351 if (IS_ERR(pchip
->bleda
))
352 return PTR_ERR(pchip
->bleda
);
355 if ((pdata
->ledb_ctrl
!= LM3630A_LEDB_DISABLE
) &&
356 (pdata
->ledb_ctrl
!= LM3630A_LEDB_ON_A
)) {
357 props
.brightness
= pdata
->ledb_init_brt
;
358 props
.max_brightness
= pdata
->ledb_max_brt
;
359 label
= pdata
->ledb_label
? pdata
->ledb_label
: "lm3630a_ledb";
361 devm_backlight_device_register(pchip
->dev
, label
,
363 &lm3630a_bank_b_ops
, &props
);
364 if (IS_ERR(pchip
->bledb
))
365 return PTR_ERR(pchip
->bledb
);
370 static const struct regmap_config lm3630a_regmap
= {
373 .max_register
= REG_MAX
,
376 static int lm3630a_parse_led_sources(struct fwnode_handle
*node
,
377 int default_led_sources
)
379 u32 sources
[LM3630A_NUM_SINKS
];
380 int ret
, num_sources
, i
;
382 num_sources
= fwnode_property_count_u32(node
, "led-sources");
384 return default_led_sources
;
385 else if (num_sources
> ARRAY_SIZE(sources
))
388 ret
= fwnode_property_read_u32_array(node
, "led-sources", sources
,
393 for (i
= 0; i
< num_sources
; i
++) {
394 if (sources
[i
] < LM3630A_SINK_0
|| sources
[i
] > LM3630A_SINK_1
)
397 ret
|= BIT(sources
[i
]);
403 static int lm3630a_parse_bank(struct lm3630a_platform_data
*pdata
,
404 struct fwnode_handle
*node
, int *seen_led_sources
)
406 int led_sources
, ret
;
411 ret
= fwnode_property_read_u32(node
, "reg", &bank
);
415 if (bank
< LM3630A_BANK_0
|| bank
> LM3630A_BANK_1
)
418 led_sources
= lm3630a_parse_led_sources(node
, BIT(bank
));
422 if (*seen_led_sources
& led_sources
)
425 *seen_led_sources
|= led_sources
;
427 linear
= fwnode_property_read_bool(node
,
428 "ti,linear-mapping-mode");
430 if (led_sources
& BIT(LM3630A_SINK_0
) ||
431 !(led_sources
& BIT(LM3630A_SINK_1
)))
434 pdata
->ledb_ctrl
= linear
?
435 LM3630A_LEDB_ENABLE_LINEAR
:
438 if (!(led_sources
& BIT(LM3630A_SINK_0
)))
441 pdata
->leda_ctrl
= linear
?
442 LM3630A_LEDA_ENABLE_LINEAR
:
445 if (led_sources
& BIT(LM3630A_SINK_1
))
446 pdata
->ledb_ctrl
= LM3630A_LEDB_ON_A
;
449 ret
= fwnode_property_read_string(node
, "label", &label
);
452 pdata
->ledb_label
= label
;
454 pdata
->leda_label
= label
;
457 ret
= fwnode_property_read_u32(node
, "default-brightness",
461 pdata
->ledb_init_brt
= val
;
463 pdata
->leda_init_brt
= val
;
466 ret
= fwnode_property_read_u32(node
, "max-brightness", &val
);
469 pdata
->ledb_max_brt
= val
;
471 pdata
->leda_max_brt
= val
;
477 static int lm3630a_parse_node(struct lm3630a_chip
*pchip
,
478 struct lm3630a_platform_data
*pdata
)
480 int ret
= -ENODEV
, seen_led_sources
= 0;
481 struct fwnode_handle
*node
;
483 device_for_each_child_node(pchip
->dev
, node
) {
484 ret
= lm3630a_parse_bank(pdata
, node
, &seen_led_sources
);
492 static int lm3630a_probe(struct i2c_client
*client
,
493 const struct i2c_device_id
*id
)
495 struct lm3630a_platform_data
*pdata
= dev_get_platdata(&client
->dev
);
496 struct lm3630a_chip
*pchip
;
499 if (!i2c_check_functionality(client
->adapter
, I2C_FUNC_I2C
)) {
500 dev_err(&client
->dev
, "fail : i2c functionality check\n");
504 pchip
= devm_kzalloc(&client
->dev
, sizeof(struct lm3630a_chip
),
508 pchip
->dev
= &client
->dev
;
510 pchip
->regmap
= devm_regmap_init_i2c(client
, &lm3630a_regmap
);
511 if (IS_ERR(pchip
->regmap
)) {
512 rval
= PTR_ERR(pchip
->regmap
);
513 dev_err(&client
->dev
, "fail : allocate reg. map: %d\n", rval
);
517 i2c_set_clientdata(client
, pchip
);
519 pdata
= devm_kzalloc(pchip
->dev
,
520 sizeof(struct lm3630a_platform_data
),
526 pdata
->leda_max_brt
= LM3630A_MAX_BRIGHTNESS
;
527 pdata
->ledb_max_brt
= LM3630A_MAX_BRIGHTNESS
;
528 pdata
->leda_init_brt
= LM3630A_MAX_BRIGHTNESS
;
529 pdata
->ledb_init_brt
= LM3630A_MAX_BRIGHTNESS
;
531 rval
= lm3630a_parse_node(pchip
, pdata
);
533 dev_err(&client
->dev
, "fail : parse node\n");
537 pchip
->pdata
= pdata
;
539 pchip
->enable_gpio
= devm_gpiod_get_optional(&client
->dev
, "enable",
541 if (IS_ERR(pchip
->enable_gpio
)) {
542 rval
= PTR_ERR(pchip
->enable_gpio
);
546 /* chip initialize */
547 rval
= lm3630a_chip_init(pchip
);
549 dev_err(&client
->dev
, "fail : init chip\n");
552 /* backlight register */
553 rval
= lm3630a_backlight_register(pchip
);
555 dev_err(&client
->dev
, "fail : backlight register.\n");
559 if (pdata
->pwm_ctrl
!= LM3630A_PWM_DISABLE
) {
560 pchip
->pwmd
= devm_pwm_get(pchip
->dev
, "lm3630a-pwm");
561 if (IS_ERR(pchip
->pwmd
)) {
562 dev_err(&client
->dev
, "fail : get pwm device\n");
563 return PTR_ERR(pchip
->pwmd
);
567 * FIXME: pwm_apply_args() should be removed when switching to
568 * the atomic PWM API.
570 pwm_apply_args(pchip
->pwmd
);
573 /* interrupt enable : irq 0 is not allowed */
574 pchip
->irq
= client
->irq
;
576 rval
= lm3630a_intr_config(pchip
);
580 dev_info(&client
->dev
, "LM3630A backlight register OK.\n");
584 static int lm3630a_remove(struct i2c_client
*client
)
587 struct lm3630a_chip
*pchip
= i2c_get_clientdata(client
);
589 rval
= lm3630a_write(pchip
, REG_BRT_A
, 0);
591 dev_err(pchip
->dev
, "i2c failed to access register\n");
593 rval
= lm3630a_write(pchip
, REG_BRT_B
, 0);
595 dev_err(pchip
->dev
, "i2c failed to access register\n");
598 free_irq(pchip
->irq
, pchip
);
599 flush_workqueue(pchip
->irqthread
);
600 destroy_workqueue(pchip
->irqthread
);
605 static const struct i2c_device_id lm3630a_id
[] = {
610 MODULE_DEVICE_TABLE(i2c
, lm3630a_id
);
612 static const struct of_device_id lm3630a_match_table
[] = {
613 { .compatible
= "ti,lm3630a", },
617 MODULE_DEVICE_TABLE(of
, lm3630a_match_table
);
619 static struct i2c_driver lm3630a_i2c_driver
= {
621 .name
= LM3630A_NAME
,
622 .of_match_table
= lm3630a_match_table
,
624 .probe
= lm3630a_probe
,
625 .remove
= lm3630a_remove
,
626 .id_table
= lm3630a_id
,
629 module_i2c_driver(lm3630a_i2c_driver
);
631 MODULE_DESCRIPTION("Texas Instruments Backlight driver for LM3630A");
632 MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
633 MODULE_AUTHOR("LDD MLP <ldd-mlp@list.ti.com>");
634 MODULE_LICENSE("GPL v2");