GNU Linux-libre 5.10.153-gnu1
[releases.git] / drivers / video / backlight / lm3630a_bl.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Simple driver for Texas Instruments LM3630A Backlight driver chip
4 * Copyright (C) 2012 Texas Instruments
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/gpio/consumer.h>
16 #include <linux/pwm.h>
17 #include <linux/platform_data/lm3630a_bl.h>
18
19 #define REG_CTRL        0x00
20 #define REG_BOOST       0x02
21 #define REG_CONFIG      0x01
22 #define REG_BRT_A       0x03
23 #define REG_BRT_B       0x04
24 #define REG_I_A         0x05
25 #define REG_I_B         0x06
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
32 #define REG_MAX         0x50
33
34 #define INT_DEBOUNCE_MSEC       10
35
36 #define LM3630A_BANK_0          0
37 #define LM3630A_BANK_1          1
38
39 #define LM3630A_NUM_SINKS       2
40 #define LM3630A_SINK_0          0
41 #define LM3630A_SINK_1          1
42
43 struct lm3630a_chip {
44         struct device *dev;
45         struct delayed_work work;
46
47         int irq;
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;
55 };
56
57 /* i2c access */
58 static int lm3630a_read(struct lm3630a_chip *pchip, unsigned int reg)
59 {
60         int rval;
61         unsigned int reg_val;
62
63         rval = regmap_read(pchip->regmap, reg, &reg_val);
64         if (rval < 0)
65                 return rval;
66         return reg_val & 0xFF;
67 }
68
69 static int lm3630a_write(struct lm3630a_chip *pchip,
70                          unsigned int reg, unsigned int data)
71 {
72         return regmap_write(pchip->regmap, reg, data);
73 }
74
75 static int lm3630a_update(struct lm3630a_chip *pchip,
76                           unsigned int reg, unsigned int mask,
77                           unsigned int data)
78 {
79         return regmap_update_bits(pchip->regmap, reg, mask, data);
80 }
81
82 /* initialize chip */
83 static int lm3630a_chip_init(struct lm3630a_chip *pchip)
84 {
85         int rval;
86         struct lm3630a_platform_data *pdata = pchip->pdata;
87
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);
95         /* set current A */
96         rval |= lm3630a_update(pchip, REG_I_A, 0x1F, 0x1F);
97         /* set current B */
98         rval |= lm3630a_write(pchip, REG_I_B, 0x1F);
99         /* set control */
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);
106
107         if (rval < 0)
108                 dev_err(pchip->dev, "i2c failed to access register\n");
109         return rval;
110 }
111
112 /* interrupt handling */
113 static void lm3630a_delayed_func(struct work_struct *work)
114 {
115         int rval;
116         struct lm3630a_chip *pchip;
117
118         pchip = container_of(work, struct lm3630a_chip, work.work);
119
120         rval = lm3630a_read(pchip, REG_INT_STATUS);
121         if (rval < 0) {
122                 dev_err(pchip->dev,
123                         "i2c failed to access REG_INT_STATUS Register\n");
124                 return;
125         }
126
127         dev_info(pchip->dev, "REG_INT_STATUS Register is 0x%x\n", rval);
128 }
129
130 static irqreturn_t lm3630a_isr_func(int irq, void *chip)
131 {
132         int rval;
133         struct lm3630a_chip *pchip = chip;
134         unsigned long delay = msecs_to_jiffies(INT_DEBOUNCE_MSEC);
135
136         queue_delayed_work(pchip->irqthread, &pchip->work, delay);
137
138         rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
139         if (rval < 0) {
140                 dev_err(pchip->dev, "i2c failed to access register\n");
141                 return IRQ_NONE;
142         }
143         return IRQ_HANDLED;
144 }
145
146 static int lm3630a_intr_config(struct lm3630a_chip *pchip)
147 {
148         int rval;
149
150         rval = lm3630a_write(pchip, REG_INT_EN, 0x87);
151         if (rval < 0)
152                 return rval;
153
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");
158                 return -ENOMEM;
159         }
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);
165                 return -ENOMEM;
166         }
167         return rval;
168 }
169
170 static void lm3630a_pwm_ctrl(struct lm3630a_chip *pchip, int br, int br_max)
171 {
172         unsigned int period = pchip->pdata->pwm_period;
173         unsigned int duty = br * period / br_max;
174
175         pwm_config(pchip->pwmd, duty, period);
176         if (duty)
177                 pwm_enable(pchip->pwmd);
178         else
179                 pwm_disable(pchip->pwmd);
180 }
181
182 /* update and get brightness */
183 static int lm3630a_bank_a_update_status(struct backlight_device *bl)
184 {
185         int ret;
186         struct lm3630a_chip *pchip = bl_get_data(bl);
187         enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
188
189         /* pwm control */
190         if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0) {
191                 lm3630a_pwm_ctrl(pchip, bl->props.brightness,
192                                  bl->props.max_brightness);
193                 return 0;
194         }
195
196         /* disable sleep */
197         ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
198         if (ret < 0)
199                 goto out_i2c_err;
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);
205         else
206                 ret |= lm3630a_update(pchip, REG_CTRL,
207                                       LM3630A_LEDA_ENABLE, LM3630A_LEDA_ENABLE);
208         if (ret < 0)
209                 goto out_i2c_err;
210         return 0;
211
212 out_i2c_err:
213         dev_err(pchip->dev, "i2c failed to access (%pe)\n", ERR_PTR(ret));
214         return ret;
215 }
216
217 static int lm3630a_bank_a_get_brightness(struct backlight_device *bl)
218 {
219         int brightness, rval;
220         struct lm3630a_chip *pchip = bl_get_data(bl);
221         enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
222
223         if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0) {
224                 rval = lm3630a_read(pchip, REG_PWM_OUTHIGH);
225                 if (rval < 0)
226                         goto out_i2c_err;
227                 brightness = (rval & 0x01) << 8;
228                 rval = lm3630a_read(pchip, REG_PWM_OUTLOW);
229                 if (rval < 0)
230                         goto out_i2c_err;
231                 brightness |= rval;
232                 goto out;
233         }
234
235         /* disable sleep */
236         rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
237         if (rval < 0)
238                 goto out_i2c_err;
239         usleep_range(1000, 2000);
240         rval = lm3630a_read(pchip, REG_BRT_A);
241         if (rval < 0)
242                 goto out_i2c_err;
243         brightness = rval;
244
245 out:
246         bl->props.brightness = brightness;
247         return bl->props.brightness;
248 out_i2c_err:
249         dev_err(pchip->dev, "i2c failed to access register\n");
250         return 0;
251 }
252
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,
257 };
258
259 /* update and get brightness */
260 static int lm3630a_bank_b_update_status(struct backlight_device *bl)
261 {
262         int ret;
263         struct lm3630a_chip *pchip = bl_get_data(bl);
264         enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
265
266         /* pwm control */
267         if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0) {
268                 lm3630a_pwm_ctrl(pchip, bl->props.brightness,
269                                  bl->props.max_brightness);
270                 return 0;
271         }
272
273         /* disable sleep */
274         ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
275         if (ret < 0)
276                 goto out_i2c_err;
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);
282         else
283                 ret |= lm3630a_update(pchip, REG_CTRL,
284                                       LM3630A_LEDB_ENABLE, LM3630A_LEDB_ENABLE);
285         if (ret < 0)
286                 goto out_i2c_err;
287         return 0;
288
289 out_i2c_err:
290         dev_err(pchip->dev, "i2c failed to access (%pe)\n", ERR_PTR(ret));
291         return ret;
292 }
293
294 static int lm3630a_bank_b_get_brightness(struct backlight_device *bl)
295 {
296         int brightness, rval;
297         struct lm3630a_chip *pchip = bl_get_data(bl);
298         enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
299
300         if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0) {
301                 rval = lm3630a_read(pchip, REG_PWM_OUTHIGH);
302                 if (rval < 0)
303                         goto out_i2c_err;
304                 brightness = (rval & 0x01) << 8;
305                 rval = lm3630a_read(pchip, REG_PWM_OUTLOW);
306                 if (rval < 0)
307                         goto out_i2c_err;
308                 brightness |= rval;
309                 goto out;
310         }
311
312         /* disable sleep */
313         rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
314         if (rval < 0)
315                 goto out_i2c_err;
316         usleep_range(1000, 2000);
317         rval = lm3630a_read(pchip, REG_BRT_B);
318         if (rval < 0)
319                 goto out_i2c_err;
320         brightness = rval;
321
322 out:
323         bl->props.brightness = brightness;
324         return bl->props.brightness;
325 out_i2c_err:
326         dev_err(pchip->dev, "i2c failed to access register\n");
327         return 0;
328 }
329
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,
334 };
335
336 static int lm3630a_backlight_register(struct lm3630a_chip *pchip)
337 {
338         struct lm3630a_platform_data *pdata = pchip->pdata;
339         struct backlight_properties props;
340         const char *label;
341
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";
347                 pchip->bleda =
348                     devm_backlight_device_register(pchip->dev, label,
349                                                    pchip->dev, pchip,
350                                                    &lm3630a_bank_a_ops, &props);
351                 if (IS_ERR(pchip->bleda))
352                         return PTR_ERR(pchip->bleda);
353         }
354
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";
360                 pchip->bledb =
361                     devm_backlight_device_register(pchip->dev, label,
362                                                    pchip->dev, pchip,
363                                                    &lm3630a_bank_b_ops, &props);
364                 if (IS_ERR(pchip->bledb))
365                         return PTR_ERR(pchip->bledb);
366         }
367         return 0;
368 }
369
370 static const struct regmap_config lm3630a_regmap = {
371         .reg_bits = 8,
372         .val_bits = 8,
373         .max_register = REG_MAX,
374 };
375
376 static int lm3630a_parse_led_sources(struct fwnode_handle *node,
377                                      int default_led_sources)
378 {
379         u32 sources[LM3630A_NUM_SINKS];
380         int ret, num_sources, i;
381
382         num_sources = fwnode_property_count_u32(node, "led-sources");
383         if (num_sources < 0)
384                 return default_led_sources;
385         else if (num_sources > ARRAY_SIZE(sources))
386                 return -EINVAL;
387
388         ret = fwnode_property_read_u32_array(node, "led-sources", sources,
389                                              num_sources);
390         if (ret)
391                 return ret;
392
393         for (i = 0; i < num_sources; i++) {
394                 if (sources[i] != LM3630A_SINK_0 && sources[i] != LM3630A_SINK_1)
395                         return -EINVAL;
396
397                 ret |= BIT(sources[i]);
398         }
399
400         return ret;
401 }
402
403 static int lm3630a_parse_bank(struct lm3630a_platform_data *pdata,
404                               struct fwnode_handle *node, int *seen_led_sources)
405 {
406         int led_sources, ret;
407         const char *label;
408         u32 bank, val;
409         bool linear;
410
411         ret = fwnode_property_read_u32(node, "reg", &bank);
412         if (ret)
413                 return ret;
414
415         if (bank != LM3630A_BANK_0 && bank != LM3630A_BANK_1)
416                 return -EINVAL;
417
418         led_sources = lm3630a_parse_led_sources(node, BIT(bank));
419         if (led_sources < 0)
420                 return led_sources;
421
422         if (*seen_led_sources & led_sources)
423                 return -EINVAL;
424
425         *seen_led_sources |= led_sources;
426
427         linear = fwnode_property_read_bool(node,
428                                            "ti,linear-mapping-mode");
429         if (bank) {
430                 if (led_sources & BIT(LM3630A_SINK_0) ||
431                     !(led_sources & BIT(LM3630A_SINK_1)))
432                         return -EINVAL;
433
434                 pdata->ledb_ctrl = linear ?
435                         LM3630A_LEDB_ENABLE_LINEAR :
436                         LM3630A_LEDB_ENABLE;
437         } else {
438                 if (!(led_sources & BIT(LM3630A_SINK_0)))
439                         return -EINVAL;
440
441                 pdata->leda_ctrl = linear ?
442                         LM3630A_LEDA_ENABLE_LINEAR :
443                         LM3630A_LEDA_ENABLE;
444
445                 if (led_sources & BIT(LM3630A_SINK_1))
446                         pdata->ledb_ctrl = LM3630A_LEDB_ON_A;
447         }
448
449         ret = fwnode_property_read_string(node, "label", &label);
450         if (!ret) {
451                 if (bank)
452                         pdata->ledb_label = label;
453                 else
454                         pdata->leda_label = label;
455         }
456
457         ret = fwnode_property_read_u32(node, "default-brightness",
458                                        &val);
459         if (!ret) {
460                 if (bank)
461                         pdata->ledb_init_brt = val;
462                 else
463                         pdata->leda_init_brt = val;
464         }
465
466         ret = fwnode_property_read_u32(node, "max-brightness", &val);
467         if (!ret) {
468                 if (bank)
469                         pdata->ledb_max_brt = val;
470                 else
471                         pdata->leda_max_brt = val;
472         }
473
474         return 0;
475 }
476
477 static int lm3630a_parse_node(struct lm3630a_chip *pchip,
478                               struct lm3630a_platform_data *pdata)
479 {
480         int ret = -ENODEV, seen_led_sources = 0;
481         struct fwnode_handle *node;
482
483         device_for_each_child_node(pchip->dev, node) {
484                 ret = lm3630a_parse_bank(pdata, node, &seen_led_sources);
485                 if (ret) {
486                         fwnode_handle_put(node);
487                         return ret;
488                 }
489         }
490
491         return ret;
492 }
493
494 static int lm3630a_probe(struct i2c_client *client,
495                          const struct i2c_device_id *id)
496 {
497         struct lm3630a_platform_data *pdata = dev_get_platdata(&client->dev);
498         struct lm3630a_chip *pchip;
499         int rval;
500
501         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
502                 dev_err(&client->dev, "fail : i2c functionality check\n");
503                 return -EOPNOTSUPP;
504         }
505
506         pchip = devm_kzalloc(&client->dev, sizeof(struct lm3630a_chip),
507                              GFP_KERNEL);
508         if (!pchip)
509                 return -ENOMEM;
510         pchip->dev = &client->dev;
511
512         pchip->regmap = devm_regmap_init_i2c(client, &lm3630a_regmap);
513         if (IS_ERR(pchip->regmap)) {
514                 rval = PTR_ERR(pchip->regmap);
515                 dev_err(&client->dev, "fail : allocate reg. map: %d\n", rval);
516                 return rval;
517         }
518
519         i2c_set_clientdata(client, pchip);
520         if (pdata == NULL) {
521                 pdata = devm_kzalloc(pchip->dev,
522                                      sizeof(struct lm3630a_platform_data),
523                                      GFP_KERNEL);
524                 if (pdata == NULL)
525                         return -ENOMEM;
526
527                 /* default values */
528                 pdata->leda_max_brt = LM3630A_MAX_BRIGHTNESS;
529                 pdata->ledb_max_brt = LM3630A_MAX_BRIGHTNESS;
530                 pdata->leda_init_brt = LM3630A_MAX_BRIGHTNESS;
531                 pdata->ledb_init_brt = LM3630A_MAX_BRIGHTNESS;
532
533                 rval = lm3630a_parse_node(pchip, pdata);
534                 if (rval) {
535                         dev_err(&client->dev, "fail : parse node\n");
536                         return rval;
537                 }
538         }
539         pchip->pdata = pdata;
540
541         pchip->enable_gpio = devm_gpiod_get_optional(&client->dev, "enable",
542                                                 GPIOD_OUT_HIGH);
543         if (IS_ERR(pchip->enable_gpio)) {
544                 rval = PTR_ERR(pchip->enable_gpio);
545                 return rval;
546         }
547
548         /* chip initialize */
549         rval = lm3630a_chip_init(pchip);
550         if (rval < 0) {
551                 dev_err(&client->dev, "fail : init chip\n");
552                 return rval;
553         }
554         /* backlight register */
555         rval = lm3630a_backlight_register(pchip);
556         if (rval < 0) {
557                 dev_err(&client->dev, "fail : backlight register.\n");
558                 return rval;
559         }
560         /* pwm */
561         if (pdata->pwm_ctrl != LM3630A_PWM_DISABLE) {
562                 pchip->pwmd = devm_pwm_get(pchip->dev, "lm3630a-pwm");
563                 if (IS_ERR(pchip->pwmd)) {
564                         dev_err(&client->dev, "fail : get pwm device\n");
565                         return PTR_ERR(pchip->pwmd);
566                 }
567
568                 /*
569                  * FIXME: pwm_apply_args() should be removed when switching to
570                  * the atomic PWM API.
571                  */
572                 pwm_apply_args(pchip->pwmd);
573         }
574
575         /* interrupt enable  : irq 0 is not allowed */
576         pchip->irq = client->irq;
577         if (pchip->irq) {
578                 rval = lm3630a_intr_config(pchip);
579                 if (rval < 0)
580                         return rval;
581         }
582         dev_info(&client->dev, "LM3630A backlight register OK.\n");
583         return 0;
584 }
585
586 static int lm3630a_remove(struct i2c_client *client)
587 {
588         int rval;
589         struct lm3630a_chip *pchip = i2c_get_clientdata(client);
590
591         rval = lm3630a_write(pchip, REG_BRT_A, 0);
592         if (rval < 0)
593                 dev_err(pchip->dev, "i2c failed to access register\n");
594
595         rval = lm3630a_write(pchip, REG_BRT_B, 0);
596         if (rval < 0)
597                 dev_err(pchip->dev, "i2c failed to access register\n");
598
599         if (pchip->irq) {
600                 free_irq(pchip->irq, pchip);
601                 flush_workqueue(pchip->irqthread);
602                 destroy_workqueue(pchip->irqthread);
603         }
604         return 0;
605 }
606
607 static const struct i2c_device_id lm3630a_id[] = {
608         {LM3630A_NAME, 0},
609         {}
610 };
611
612 MODULE_DEVICE_TABLE(i2c, lm3630a_id);
613
614 static const struct of_device_id lm3630a_match_table[] = {
615         { .compatible = "ti,lm3630a", },
616         { },
617 };
618
619 MODULE_DEVICE_TABLE(of, lm3630a_match_table);
620
621 static struct i2c_driver lm3630a_i2c_driver = {
622         .driver = {
623                    .name = LM3630A_NAME,
624                    .of_match_table = lm3630a_match_table,
625                    },
626         .probe = lm3630a_probe,
627         .remove = lm3630a_remove,
628         .id_table = lm3630a_id,
629 };
630
631 module_i2c_driver(lm3630a_i2c_driver);
632
633 MODULE_DESCRIPTION("Texas Instruments Backlight driver for LM3630A");
634 MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
635 MODULE_AUTHOR("LDD MLP <ldd-mlp@list.ti.com>");
636 MODULE_LICENSE("GPL v2");