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5
6#include <linux/module.h>
7#include <linux/slab.h>
8#include <linux/i2c.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/pwm.h>
16#include <linux/platform_data/lm3630a_bl.h>
17
18#define REG_CTRL 0x00
19#define REG_BOOST 0x02
20#define REG_CONFIG 0x01
21#define REG_BRT_A 0x03
22#define REG_BRT_B 0x04
23#define REG_I_A 0x05
24#define REG_I_B 0x06
25#define REG_INT_STATUS 0x09
26#define REG_INT_EN 0x0A
27#define REG_FAULT 0x0B
28#define REG_PWM_OUTLOW 0x12
29#define REG_PWM_OUTHIGH 0x13
30#define REG_FILTER_STRENGTH 0x50
31#define REG_MAX 0x50
32
33#define INT_DEBOUNCE_MSEC 10
34
35#define LM3630A_BANK_0 0
36#define LM3630A_BANK_1 1
37
38#define LM3630A_NUM_SINKS 2
39#define LM3630A_SINK_0 0
40#define LM3630A_SINK_1 1
41
42struct lm3630a_chip {
43 struct device *dev;
44 struct delayed_work work;
45
46 int irq;
47 struct workqueue_struct *irqthread;
48 struct lm3630a_platform_data *pdata;
49 struct backlight_device *bleda;
50 struct backlight_device *bledb;
51 struct regmap *regmap;
52 struct pwm_device *pwmd;
53};
54
55
56static int lm3630a_read(struct lm3630a_chip *pchip, unsigned int reg)
57{
58 int rval;
59 unsigned int reg_val;
60
61 rval = regmap_read(pchip->regmap, reg, ®_val);
62 if (rval < 0)
63 return rval;
64 return reg_val & 0xFF;
65}
66
67static int lm3630a_write(struct lm3630a_chip *pchip,
68 unsigned int reg, unsigned int data)
69{
70 return regmap_write(pchip->regmap, reg, data);
71}
72
73static int lm3630a_update(struct lm3630a_chip *pchip,
74 unsigned int reg, unsigned int mask,
75 unsigned int data)
76{
77 return regmap_update_bits(pchip->regmap, reg, mask, data);
78}
79
80
81static int lm3630a_chip_init(struct lm3630a_chip *pchip)
82{
83 int rval;
84 struct lm3630a_platform_data *pdata = pchip->pdata;
85
86 usleep_range(1000, 2000);
87
88 rval = lm3630a_write(pchip, REG_FILTER_STRENGTH, 0x03);
89
90 rval |= lm3630a_update(pchip, REG_CONFIG, 0x07, pdata->pwm_ctrl);
91
92 rval |= lm3630a_write(pchip, REG_BOOST, 0x38);
93
94 rval |= lm3630a_update(pchip, REG_I_A, 0x1F, 0x1F);
95
96 rval |= lm3630a_write(pchip, REG_I_B, 0x1F);
97
98 rval |= lm3630a_update(pchip, REG_CTRL, 0x14, pdata->leda_ctrl);
99 rval |= lm3630a_update(pchip, REG_CTRL, 0x0B, pdata->ledb_ctrl);
100 usleep_range(1000, 2000);
101
102 rval |= lm3630a_write(pchip, REG_BRT_A, pdata->leda_init_brt);
103 rval |= lm3630a_write(pchip, REG_BRT_B, pdata->ledb_init_brt);
104
105 if (rval < 0)
106 dev_err(pchip->dev, "i2c failed to access register\n");
107 return rval;
108}
109
110
111static void lm3630a_delayed_func(struct work_struct *work)
112{
113 int rval;
114 struct lm3630a_chip *pchip;
115
116 pchip = container_of(work, struct lm3630a_chip, work.work);
117
118 rval = lm3630a_read(pchip, REG_INT_STATUS);
119 if (rval < 0) {
120 dev_err(pchip->dev,
121 "i2c failed to access REG_INT_STATUS Register\n");
122 return;
123 }
124
125 dev_info(pchip->dev, "REG_INT_STATUS Register is 0x%x\n", rval);
126}
127
128static irqreturn_t lm3630a_isr_func(int irq, void *chip)
129{
130 int rval;
131 struct lm3630a_chip *pchip = chip;
132 unsigned long delay = msecs_to_jiffies(INT_DEBOUNCE_MSEC);
133
134 queue_delayed_work(pchip->irqthread, &pchip->work, delay);
135
136 rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
137 if (rval < 0) {
138 dev_err(pchip->dev, "i2c failed to access register\n");
139 return IRQ_NONE;
140 }
141 return IRQ_HANDLED;
142}
143
144static int lm3630a_intr_config(struct lm3630a_chip *pchip)
145{
146 int rval;
147
148 rval = lm3630a_write(pchip, REG_INT_EN, 0x87);
149 if (rval < 0)
150 return rval;
151
152 INIT_DELAYED_WORK(&pchip->work, lm3630a_delayed_func);
153 pchip->irqthread = create_singlethread_workqueue("lm3630a-irqthd");
154 if (!pchip->irqthread) {
155 dev_err(pchip->dev, "create irq thread fail\n");
156 return -ENOMEM;
157 }
158 if (request_threaded_irq
159 (pchip->irq, NULL, lm3630a_isr_func,
160 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, "lm3630a_irq", pchip)) {
161 dev_err(pchip->dev, "request threaded irq fail\n");
162 destroy_workqueue(pchip->irqthread);
163 return -ENOMEM;
164 }
165 return rval;
166}
167
168static void lm3630a_pwm_ctrl(struct lm3630a_chip *pchip, int br, int br_max)
169{
170 unsigned int period = pchip->pdata->pwm_period;
171 unsigned int duty = br * period / br_max;
172
173 pwm_config(pchip->pwmd, duty, period);
174 if (duty)
175 pwm_enable(pchip->pwmd);
176 else
177 pwm_disable(pchip->pwmd);
178}
179
180
181static int lm3630a_bank_a_update_status(struct backlight_device *bl)
182{
183 int ret;
184 struct lm3630a_chip *pchip = bl_get_data(bl);
185 enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
186
187
188 if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0) {
189 lm3630a_pwm_ctrl(pchip, bl->props.brightness,
190 bl->props.max_brightness);
191 return bl->props.brightness;
192 }
193
194
195 ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
196 if (ret < 0)
197 goto out_i2c_err;
198 usleep_range(1000, 2000);
199
200 ret = lm3630a_write(pchip, REG_BRT_A, bl->props.brightness);
201 if (bl->props.brightness < 0x4)
202 ret |= lm3630a_update(pchip, REG_CTRL, LM3630A_LEDA_ENABLE, 0);
203 else
204 ret |= lm3630a_update(pchip, REG_CTRL,
205 LM3630A_LEDA_ENABLE, LM3630A_LEDA_ENABLE);
206 if (ret < 0)
207 goto out_i2c_err;
208 return 0;
209
210out_i2c_err:
211 dev_err(pchip->dev, "i2c failed to access\n");
212 return bl->props.brightness;
213}
214
215static int lm3630a_bank_a_get_brightness(struct backlight_device *bl)
216{
217 int brightness, rval;
218 struct lm3630a_chip *pchip = bl_get_data(bl);
219 enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
220
221 if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0) {
222 rval = lm3630a_read(pchip, REG_PWM_OUTHIGH);
223 if (rval < 0)
224 goto out_i2c_err;
225 brightness = (rval & 0x01) << 8;
226 rval = lm3630a_read(pchip, REG_PWM_OUTLOW);
227 if (rval < 0)
228 goto out_i2c_err;
229 brightness |= rval;
230 goto out;
231 }
232
233
234 rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
235 if (rval < 0)
236 goto out_i2c_err;
237 usleep_range(1000, 2000);
238 rval = lm3630a_read(pchip, REG_BRT_A);
239 if (rval < 0)
240 goto out_i2c_err;
241 brightness = rval;
242
243out:
244 bl->props.brightness = brightness;
245 return bl->props.brightness;
246out_i2c_err:
247 dev_err(pchip->dev, "i2c failed to access register\n");
248 return 0;
249}
250
251static const struct backlight_ops lm3630a_bank_a_ops = {
252 .options = BL_CORE_SUSPENDRESUME,
253 .update_status = lm3630a_bank_a_update_status,
254 .get_brightness = lm3630a_bank_a_get_brightness,
255};
256
257
258static int lm3630a_bank_b_update_status(struct backlight_device *bl)
259{
260 int ret;
261 struct lm3630a_chip *pchip = bl_get_data(bl);
262 enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
263
264
265 if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0) {
266 lm3630a_pwm_ctrl(pchip, bl->props.brightness,
267 bl->props.max_brightness);
268 return bl->props.brightness;
269 }
270
271
272 ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
273 if (ret < 0)
274 goto out_i2c_err;
275 usleep_range(1000, 2000);
276
277 ret = lm3630a_write(pchip, REG_BRT_B, bl->props.brightness);
278 if (bl->props.brightness < 0x4)
279 ret |= lm3630a_update(pchip, REG_CTRL, LM3630A_LEDB_ENABLE, 0);
280 else
281 ret |= lm3630a_update(pchip, REG_CTRL,
282 LM3630A_LEDB_ENABLE, LM3630A_LEDB_ENABLE);
283 if (ret < 0)
284 goto out_i2c_err;
285 return 0;
286
287out_i2c_err:
288 dev_err(pchip->dev, "i2c failed to access REG_CTRL\n");
289 return bl->props.brightness;
290}
291
292static int lm3630a_bank_b_get_brightness(struct backlight_device *bl)
293{
294 int brightness, rval;
295 struct lm3630a_chip *pchip = bl_get_data(bl);
296 enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
297
298 if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0) {
299 rval = lm3630a_read(pchip, REG_PWM_OUTHIGH);
300 if (rval < 0)
301 goto out_i2c_err;
302 brightness = (rval & 0x01) << 8;
303 rval = lm3630a_read(pchip, REG_PWM_OUTLOW);
304 if (rval < 0)
305 goto out_i2c_err;
306 brightness |= rval;
307 goto out;
308 }
309
310
311 rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
312 if (rval < 0)
313 goto out_i2c_err;
314 usleep_range(1000, 2000);
315 rval = lm3630a_read(pchip, REG_BRT_B);
316 if (rval < 0)
317 goto out_i2c_err;
318 brightness = rval;
319
320out:
321 bl->props.brightness = brightness;
322 return bl->props.brightness;
323out_i2c_err:
324 dev_err(pchip->dev, "i2c failed to access register\n");
325 return 0;
326}
327
328static const struct backlight_ops lm3630a_bank_b_ops = {
329 .options = BL_CORE_SUSPENDRESUME,
330 .update_status = lm3630a_bank_b_update_status,
331 .get_brightness = lm3630a_bank_b_get_brightness,
332};
333
334static int lm3630a_backlight_register(struct lm3630a_chip *pchip)
335{
336 struct lm3630a_platform_data *pdata = pchip->pdata;
337 struct backlight_properties props;
338 const char *label;
339
340 props.type = BACKLIGHT_RAW;
341 if (pdata->leda_ctrl != LM3630A_LEDA_DISABLE) {
342 props.brightness = pdata->leda_init_brt;
343 props.max_brightness = pdata->leda_max_brt;
344 label = pdata->leda_label ? pdata->leda_label : "lm3630a_leda";
345 pchip->bleda =
346 devm_backlight_device_register(pchip->dev, label,
347 pchip->dev, pchip,
348 &lm3630a_bank_a_ops, &props);
349 if (IS_ERR(pchip->bleda))
350 return PTR_ERR(pchip->bleda);
351 }
352
353 if ((pdata->ledb_ctrl != LM3630A_LEDB_DISABLE) &&
354 (pdata->ledb_ctrl != LM3630A_LEDB_ON_A)) {
355 props.brightness = pdata->ledb_init_brt;
356 props.max_brightness = pdata->ledb_max_brt;
357 label = pdata->ledb_label ? pdata->ledb_label : "lm3630a_ledb";
358 pchip->bledb =
359 devm_backlight_device_register(pchip->dev, label,
360 pchip->dev, pchip,
361 &lm3630a_bank_b_ops, &props);
362 if (IS_ERR(pchip->bledb))
363 return PTR_ERR(pchip->bledb);
364 }
365 return 0;
366}
367
368static const struct regmap_config lm3630a_regmap = {
369 .reg_bits = 8,
370 .val_bits = 8,
371 .max_register = REG_MAX,
372};
373
374static int lm3630a_parse_led_sources(struct fwnode_handle *node,
375 int default_led_sources)
376{
377 u32 sources[LM3630A_NUM_SINKS];
378 int ret, num_sources, i;
379
380 num_sources = fwnode_property_read_u32_array(node, "led-sources", NULL,
381 0);
382 if (num_sources < 0)
383 return default_led_sources;
384 else if (num_sources > ARRAY_SIZE(sources))
385 return -EINVAL;
386
387 ret = fwnode_property_read_u32_array(node, "led-sources", sources,
388 num_sources);
389 if (ret)
390 return ret;
391
392 for (i = 0; i < num_sources; i++) {
393 if (sources[i] < LM3630A_SINK_0 || sources[i] > LM3630A_SINK_1)
394 return -EINVAL;
395
396 ret |= BIT(sources[i]);
397 }
398
399 return ret;
400}
401
402static int lm3630a_parse_bank(struct lm3630a_platform_data *pdata,
403 struct fwnode_handle *node, int *seen_led_sources)
404{
405 int led_sources, ret;
406 const char *label;
407 u32 bank, val;
408 bool linear;
409
410 ret = fwnode_property_read_u32(node, "reg", &bank);
411 if (ret)
412 return ret;
413
414 if (bank < LM3630A_BANK_0 || bank > LM3630A_BANK_1)
415 return -EINVAL;
416
417 led_sources = lm3630a_parse_led_sources(node, BIT(bank));
418 if (led_sources < 0)
419 return led_sources;
420
421 if (*seen_led_sources & led_sources)
422 return -EINVAL;
423
424 *seen_led_sources |= led_sources;
425
426 linear = fwnode_property_read_bool(node,
427 "ti,linear-mapping-mode");
428 if (bank) {
429 if (led_sources & BIT(LM3630A_SINK_0) ||
430 !(led_sources & BIT(LM3630A_SINK_1)))
431 return -EINVAL;
432
433 pdata->ledb_ctrl = linear ?
434 LM3630A_LEDB_ENABLE_LINEAR :
435 LM3630A_LEDB_ENABLE;
436 } else {
437 if (!(led_sources & BIT(LM3630A_SINK_0)))
438 return -EINVAL;
439
440 pdata->leda_ctrl = linear ?
441 LM3630A_LEDA_ENABLE_LINEAR :
442 LM3630A_LEDA_ENABLE;
443
444 if (led_sources & BIT(LM3630A_SINK_1))
445 pdata->ledb_ctrl = LM3630A_LEDB_ON_A;
446 }
447
448 ret = fwnode_property_read_string(node, "label", &label);
449 if (!ret) {
450 if (bank)
451 pdata->ledb_label = label;
452 else
453 pdata->leda_label = label;
454 }
455
456 ret = fwnode_property_read_u32(node, "default-brightness",
457 &val);
458 if (!ret) {
459 if (bank)
460 pdata->ledb_init_brt = val;
461 else
462 pdata->leda_init_brt = val;
463 }
464
465 ret = fwnode_property_read_u32(node, "max-brightness", &val);
466 if (!ret) {
467 if (bank)
468 pdata->ledb_max_brt = val;
469 else
470 pdata->leda_max_brt = val;
471 }
472
473 return 0;
474}
475
476static int lm3630a_parse_node(struct lm3630a_chip *pchip,
477 struct lm3630a_platform_data *pdata)
478{
479 int ret = -ENODEV, seen_led_sources = 0;
480 struct fwnode_handle *node;
481
482 device_for_each_child_node(pchip->dev, node) {
483 ret = lm3630a_parse_bank(pdata, node, &seen_led_sources);
484 if (ret)
485 return ret;
486 }
487
488 return ret;
489}
490
491static int lm3630a_probe(struct i2c_client *client,
492 const struct i2c_device_id *id)
493{
494 struct lm3630a_platform_data *pdata = dev_get_platdata(&client->dev);
495 struct lm3630a_chip *pchip;
496 int rval;
497
498 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
499 dev_err(&client->dev, "fail : i2c functionality check\n");
500 return -EOPNOTSUPP;
501 }
502
503 pchip = devm_kzalloc(&client->dev, sizeof(struct lm3630a_chip),
504 GFP_KERNEL);
505 if (!pchip)
506 return -ENOMEM;
507 pchip->dev = &client->dev;
508
509 pchip->regmap = devm_regmap_init_i2c(client, &lm3630a_regmap);
510 if (IS_ERR(pchip->regmap)) {
511 rval = PTR_ERR(pchip->regmap);
512 dev_err(&client->dev, "fail : allocate reg. map: %d\n", rval);
513 return rval;
514 }
515
516 i2c_set_clientdata(client, pchip);
517 if (pdata == NULL) {
518 pdata = devm_kzalloc(pchip->dev,
519 sizeof(struct lm3630a_platform_data),
520 GFP_KERNEL);
521 if (pdata == NULL)
522 return -ENOMEM;
523
524
525 pdata->leda_max_brt = LM3630A_MAX_BRIGHTNESS;
526 pdata->ledb_max_brt = LM3630A_MAX_BRIGHTNESS;
527 pdata->leda_init_brt = LM3630A_MAX_BRIGHTNESS;
528 pdata->ledb_init_brt = LM3630A_MAX_BRIGHTNESS;
529
530 rval = lm3630a_parse_node(pchip, pdata);
531 if (rval) {
532 dev_err(&client->dev, "fail : parse node\n");
533 return rval;
534 }
535 }
536 pchip->pdata = pdata;
537
538
539 rval = lm3630a_chip_init(pchip);
540 if (rval < 0) {
541 dev_err(&client->dev, "fail : init chip\n");
542 return rval;
543 }
544
545 rval = lm3630a_backlight_register(pchip);
546 if (rval < 0) {
547 dev_err(&client->dev, "fail : backlight register.\n");
548 return rval;
549 }
550
551 if (pdata->pwm_ctrl != LM3630A_PWM_DISABLE) {
552 pchip->pwmd = devm_pwm_get(pchip->dev, "lm3630a-pwm");
553 if (IS_ERR(pchip->pwmd)) {
554 dev_err(&client->dev, "fail : get pwm device\n");
555 return PTR_ERR(pchip->pwmd);
556 }
557
558
559
560
561
562 pwm_apply_args(pchip->pwmd);
563 }
564
565
566 pchip->irq = client->irq;
567 if (pchip->irq) {
568 rval = lm3630a_intr_config(pchip);
569 if (rval < 0)
570 return rval;
571 }
572 dev_info(&client->dev, "LM3630A backlight register OK.\n");
573 return 0;
574}
575
576static int lm3630a_remove(struct i2c_client *client)
577{
578 int rval;
579 struct lm3630a_chip *pchip = i2c_get_clientdata(client);
580
581 rval = lm3630a_write(pchip, REG_BRT_A, 0);
582 if (rval < 0)
583 dev_err(pchip->dev, "i2c failed to access register\n");
584
585 rval = lm3630a_write(pchip, REG_BRT_B, 0);
586 if (rval < 0)
587 dev_err(pchip->dev, "i2c failed to access register\n");
588
589 if (pchip->irq) {
590 free_irq(pchip->irq, pchip);
591 flush_workqueue(pchip->irqthread);
592 destroy_workqueue(pchip->irqthread);
593 }
594 return 0;
595}
596
597static const struct i2c_device_id lm3630a_id[] = {
598 {LM3630A_NAME, 0},
599 {}
600};
601
602static const struct of_device_id lm3630a_match_table[] = {
603 { .compatible = "ti,lm3630a", },
604 { },
605};
606
607MODULE_DEVICE_TABLE(i2c, lm3630a_id);
608
609static struct i2c_driver lm3630a_i2c_driver = {
610 .driver = {
611 .name = LM3630A_NAME,
612 .of_match_table = lm3630a_match_table,
613 },
614 .probe = lm3630a_probe,
615 .remove = lm3630a_remove,
616 .id_table = lm3630a_id,
617};
618
619module_i2c_driver(lm3630a_i2c_driver);
620
621MODULE_DESCRIPTION("Texas Instruments Backlight driver for LM3630A");
622MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
623MODULE_AUTHOR("LDD MLP <ldd-mlp@list.ti.com>");
624MODULE_LICENSE("GPL v2");
625
