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[linux.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         struct pwm_state pwmd_state;
56 };
57
58 /* i2c access */
59 static int lm3630a_read(struct lm3630a_chip *pchip, unsigned int reg)
60 {
61         int rval;
62         unsigned int reg_val;
63
64         rval = regmap_read(pchip->regmap, reg, &reg_val);
65         if (rval < 0)
66                 return rval;
67         return reg_val & 0xFF;
68 }
69
70 static int lm3630a_write(struct lm3630a_chip *pchip,
71                          unsigned int reg, unsigned int data)
72 {
73         return regmap_write(pchip->regmap, reg, data);
74 }
75
76 static int lm3630a_update(struct lm3630a_chip *pchip,
77                           unsigned int reg, unsigned int mask,
78                           unsigned int data)
79 {
80         return regmap_update_bits(pchip->regmap, reg, mask, data);
81 }
82
83 /* initialize chip */
84 static int lm3630a_chip_init(struct lm3630a_chip *pchip)
85 {
86         int rval;
87         struct lm3630a_platform_data *pdata = pchip->pdata;
88
89         usleep_range(1000, 2000);
90         /* set Filter Strength Register */
91         rval = lm3630a_write(pchip, REG_FILTER_STRENGTH, 0x03);
92         /* set Cofig. register */
93         rval |= lm3630a_update(pchip, REG_CONFIG, 0x07, pdata->pwm_ctrl);
94         /* set boost control */
95         rval |= lm3630a_write(pchip, REG_BOOST, 0x38);
96         /* set current A */
97         rval |= lm3630a_update(pchip, REG_I_A, 0x1F, 0x1F);
98         /* set current B */
99         rval |= lm3630a_write(pchip, REG_I_B, 0x1F);
100         /* set control */
101         rval |= lm3630a_update(pchip, REG_CTRL, 0x14, pdata->leda_ctrl);
102         rval |= lm3630a_update(pchip, REG_CTRL, 0x0B, pdata->ledb_ctrl);
103         usleep_range(1000, 2000);
104         /* set brightness A and B */
105         rval |= lm3630a_write(pchip, REG_BRT_A, pdata->leda_init_brt);
106         rval |= lm3630a_write(pchip, REG_BRT_B, pdata->ledb_init_brt);
107
108         if (rval < 0)
109                 dev_err(pchip->dev, "i2c failed to access register\n");
110         return rval;
111 }
112
113 /* interrupt handling */
114 static void lm3630a_delayed_func(struct work_struct *work)
115 {
116         int rval;
117         struct lm3630a_chip *pchip;
118
119         pchip = container_of(work, struct lm3630a_chip, work.work);
120
121         rval = lm3630a_read(pchip, REG_INT_STATUS);
122         if (rval < 0) {
123                 dev_err(pchip->dev,
124                         "i2c failed to access REG_INT_STATUS Register\n");
125                 return;
126         }
127
128         dev_info(pchip->dev, "REG_INT_STATUS Register is 0x%x\n", rval);
129 }
130
131 static irqreturn_t lm3630a_isr_func(int irq, void *chip)
132 {
133         int rval;
134         struct lm3630a_chip *pchip = chip;
135         unsigned long delay = msecs_to_jiffies(INT_DEBOUNCE_MSEC);
136
137         queue_delayed_work(pchip->irqthread, &pchip->work, delay);
138
139         rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
140         if (rval < 0) {
141                 dev_err(pchip->dev, "i2c failed to access register\n");
142                 return IRQ_NONE;
143         }
144         return IRQ_HANDLED;
145 }
146
147 static int lm3630a_intr_config(struct lm3630a_chip *pchip)
148 {
149         int rval;
150
151         rval = lm3630a_write(pchip, REG_INT_EN, 0x87);
152         if (rval < 0)
153                 return rval;
154
155         INIT_DELAYED_WORK(&pchip->work, lm3630a_delayed_func);
156         pchip->irqthread = create_singlethread_workqueue("lm3630a-irqthd");
157         if (!pchip->irqthread) {
158                 dev_err(pchip->dev, "create irq thread fail\n");
159                 return -ENOMEM;
160         }
161         if (request_threaded_irq
162             (pchip->irq, NULL, lm3630a_isr_func,
163              IRQF_TRIGGER_FALLING | IRQF_ONESHOT, "lm3630a_irq", pchip)) {
164                 dev_err(pchip->dev, "request threaded irq fail\n");
165                 destroy_workqueue(pchip->irqthread);
166                 return -ENOMEM;
167         }
168         return rval;
169 }
170
171 static int lm3630a_pwm_ctrl(struct lm3630a_chip *pchip, int br, int br_max)
172 {
173         int err;
174
175         pchip->pwmd_state.period = pchip->pdata->pwm_period;
176
177         err = pwm_set_relative_duty_cycle(&pchip->pwmd_state, br, br_max);
178         if (err)
179                 return err;
180
181         pchip->pwmd_state.enabled = pchip->pwmd_state.duty_cycle ? true : false;
182
183         return pwm_apply_might_sleep(pchip->pwmd, &pchip->pwmd_state);
184 }
185
186 /* update and get brightness */
187 static int lm3630a_bank_a_update_status(struct backlight_device *bl)
188 {
189         int ret;
190         struct lm3630a_chip *pchip = bl_get_data(bl);
191         enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
192         int brightness = backlight_get_brightness(bl);
193
194         /* pwm control */
195         if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0)
196                 return lm3630a_pwm_ctrl(pchip, brightness,
197                                         bl->props.max_brightness);
198
199         /* disable sleep */
200         ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
201         if (ret < 0)
202                 goto out_i2c_err;
203         usleep_range(1000, 2000);
204         /* minimum brightness is 0x04 */
205         ret = lm3630a_write(pchip, REG_BRT_A, brightness);
206
207         if (brightness < 0x4)
208                 /* turn the string off  */
209                 ret |= lm3630a_update(pchip, REG_CTRL, LM3630A_LEDA_ENABLE, 0);
210         else
211                 ret |= lm3630a_update(pchip, REG_CTRL,
212                                       LM3630A_LEDA_ENABLE, LM3630A_LEDA_ENABLE);
213         if (ret < 0)
214                 goto out_i2c_err;
215         return 0;
216
217 out_i2c_err:
218         dev_err(pchip->dev, "i2c failed to access (%pe)\n", ERR_PTR(ret));
219         return ret;
220 }
221
222 static int lm3630a_bank_a_get_brightness(struct backlight_device *bl)
223 {
224         int brightness, rval;
225         struct lm3630a_chip *pchip = bl_get_data(bl);
226         enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
227
228         if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0) {
229                 rval = lm3630a_read(pchip, REG_PWM_OUTHIGH);
230                 if (rval < 0)
231                         goto out_i2c_err;
232                 brightness = (rval & 0x01) << 8;
233                 rval = lm3630a_read(pchip, REG_PWM_OUTLOW);
234                 if (rval < 0)
235                         goto out_i2c_err;
236                 brightness |= rval;
237                 return brightness;
238         }
239
240         /* disable sleep */
241         rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
242         if (rval < 0)
243                 goto out_i2c_err;
244         usleep_range(1000, 2000);
245         rval = lm3630a_read(pchip, REG_BRT_A);
246         if (rval < 0)
247                 goto out_i2c_err;
248         return rval;
249
250 out_i2c_err:
251         dev_err(pchip->dev, "i2c failed to access register\n");
252         return 0;
253 }
254
255 static const struct backlight_ops lm3630a_bank_a_ops = {
256         .options = BL_CORE_SUSPENDRESUME,
257         .update_status = lm3630a_bank_a_update_status,
258         .get_brightness = lm3630a_bank_a_get_brightness,
259 };
260
261 /* update and get brightness */
262 static int lm3630a_bank_b_update_status(struct backlight_device *bl)
263 {
264         int ret;
265         struct lm3630a_chip *pchip = bl_get_data(bl);
266         enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
267         int brightness = backlight_get_brightness(bl);
268
269         /* pwm control */
270         if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0)
271                 return lm3630a_pwm_ctrl(pchip, brightness,
272                                         bl->props.max_brightness);
273
274         /* disable sleep */
275         ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
276         if (ret < 0)
277                 goto out_i2c_err;
278         usleep_range(1000, 2000);
279         /* minimum brightness is 0x04 */
280         ret = lm3630a_write(pchip, REG_BRT_B, brightness);
281
282         if (brightness < 0x4)
283                 /* turn the string off  */
284                 ret |= lm3630a_update(pchip, REG_CTRL, LM3630A_LEDB_ENABLE, 0);
285         else
286                 ret |= lm3630a_update(pchip, REG_CTRL,
287                                       LM3630A_LEDB_ENABLE, LM3630A_LEDB_ENABLE);
288         if (ret < 0)
289                 goto out_i2c_err;
290         return 0;
291
292 out_i2c_err:
293         dev_err(pchip->dev, "i2c failed to access (%pe)\n", ERR_PTR(ret));
294         return ret;
295 }
296
297 static int lm3630a_bank_b_get_brightness(struct backlight_device *bl)
298 {
299         int brightness, rval;
300         struct lm3630a_chip *pchip = bl_get_data(bl);
301         enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
302
303         if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0) {
304                 rval = lm3630a_read(pchip, REG_PWM_OUTHIGH);
305                 if (rval < 0)
306                         goto out_i2c_err;
307                 brightness = (rval & 0x01) << 8;
308                 rval = lm3630a_read(pchip, REG_PWM_OUTLOW);
309                 if (rval < 0)
310                         goto out_i2c_err;
311                 brightness |= rval;
312                 return brightness;
313         }
314
315         /* disable sleep */
316         rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
317         if (rval < 0)
318                 goto out_i2c_err;
319         usleep_range(1000, 2000);
320         rval = lm3630a_read(pchip, REG_BRT_B);
321         if (rval < 0)
322                 goto out_i2c_err;
323         return rval;
324
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         memset(&props, 0, sizeof(struct backlight_properties));
343         props.type = BACKLIGHT_RAW;
344         if (pdata->leda_ctrl != LM3630A_LEDA_DISABLE) {
345                 props.brightness = pdata->leda_init_brt;
346                 props.max_brightness = pdata->leda_max_brt;
347                 label = pdata->leda_label ? pdata->leda_label : "lm3630a_leda";
348                 pchip->bleda =
349                     devm_backlight_device_register(pchip->dev, label,
350                                                    pchip->dev, pchip,
351                                                    &lm3630a_bank_a_ops, &props);
352                 if (IS_ERR(pchip->bleda))
353                         return PTR_ERR(pchip->bleda);
354         }
355
356         if ((pdata->ledb_ctrl != LM3630A_LEDB_DISABLE) &&
357             (pdata->ledb_ctrl != LM3630A_LEDB_ON_A)) {
358                 props.brightness = pdata->ledb_init_brt;
359                 props.max_brightness = pdata->ledb_max_brt;
360                 label = pdata->ledb_label ? pdata->ledb_label : "lm3630a_ledb";
361                 pchip->bledb =
362                     devm_backlight_device_register(pchip->dev, label,
363                                                    pchip->dev, pchip,
364                                                    &lm3630a_bank_b_ops, &props);
365                 if (IS_ERR(pchip->bledb))
366                         return PTR_ERR(pchip->bledb);
367         }
368         return 0;
369 }
370
371 static const struct regmap_config lm3630a_regmap = {
372         .reg_bits = 8,
373         .val_bits = 8,
374         .max_register = REG_MAX,
375 };
376
377 static int lm3630a_parse_led_sources(struct fwnode_handle *node,
378                                      int default_led_sources)
379 {
380         u32 sources[LM3630A_NUM_SINKS];
381         int ret, num_sources, i;
382
383         num_sources = fwnode_property_count_u32(node, "led-sources");
384         if (num_sources < 0)
385                 return default_led_sources;
386         else if (num_sources > ARRAY_SIZE(sources))
387                 return -EINVAL;
388
389         ret = fwnode_property_read_u32_array(node, "led-sources", sources,
390                                              num_sources);
391         if (ret)
392                 return ret;
393
394         for (i = 0; i < num_sources; i++) {
395                 if (sources[i] != LM3630A_SINK_0 && sources[i] != LM3630A_SINK_1)
396                         return -EINVAL;
397
398                 ret |= BIT(sources[i]);
399         }
400
401         return ret;
402 }
403
404 static int lm3630a_parse_bank(struct lm3630a_platform_data *pdata,
405                               struct fwnode_handle *node, int *seen_led_sources)
406 {
407         int led_sources, ret;
408         const char *label;
409         u32 bank, val;
410         bool linear;
411
412         ret = fwnode_property_read_u32(node, "reg", &bank);
413         if (ret)
414                 return ret;
415
416         if (bank != LM3630A_BANK_0 && bank != LM3630A_BANK_1)
417                 return -EINVAL;
418
419         led_sources = lm3630a_parse_led_sources(node, BIT(bank));
420         if (led_sources < 0)
421                 return led_sources;
422
423         if (*seen_led_sources & led_sources)
424                 return -EINVAL;
425
426         *seen_led_sources |= led_sources;
427
428         linear = fwnode_property_read_bool(node,
429                                            "ti,linear-mapping-mode");
430         if (bank) {
431                 if (led_sources & BIT(LM3630A_SINK_0) ||
432                     !(led_sources & BIT(LM3630A_SINK_1)))
433                         return -EINVAL;
434
435                 pdata->ledb_ctrl = linear ?
436                         LM3630A_LEDB_ENABLE_LINEAR :
437                         LM3630A_LEDB_ENABLE;
438         } else {
439                 if (!(led_sources & BIT(LM3630A_SINK_0)))
440                         return -EINVAL;
441
442                 pdata->leda_ctrl = linear ?
443                         LM3630A_LEDA_ENABLE_LINEAR :
444                         LM3630A_LEDA_ENABLE;
445
446                 if (led_sources & BIT(LM3630A_SINK_1))
447                         pdata->ledb_ctrl = LM3630A_LEDB_ON_A;
448         }
449
450         ret = fwnode_property_read_string(node, "label", &label);
451         if (!ret) {
452                 if (bank)
453                         pdata->ledb_label = label;
454                 else
455                         pdata->leda_label = label;
456         }
457
458         ret = fwnode_property_read_u32(node, "default-brightness",
459                                        &val);
460         if (!ret) {
461                 if (bank)
462                         pdata->ledb_init_brt = val;
463                 else
464                         pdata->leda_init_brt = val;
465         }
466
467         ret = fwnode_property_read_u32(node, "max-brightness", &val);
468         if (!ret) {
469                 if (bank)
470                         pdata->ledb_max_brt = val;
471                 else
472                         pdata->leda_max_brt = val;
473         }
474
475         return 0;
476 }
477
478 static int lm3630a_parse_node(struct lm3630a_chip *pchip,
479                               struct lm3630a_platform_data *pdata)
480 {
481         int ret = -ENODEV, seen_led_sources = 0;
482         struct fwnode_handle *node;
483
484         device_for_each_child_node(pchip->dev, node) {
485                 ret = lm3630a_parse_bank(pdata, node, &seen_led_sources);
486                 if (ret) {
487                         fwnode_handle_put(node);
488                         return ret;
489                 }
490         }
491
492         return ret;
493 }
494
495 static int lm3630a_probe(struct i2c_client *client)
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                 return PTR_ERR(pchip->enable_gpio);
545
546         /* chip initialize */
547         rval = lm3630a_chip_init(pchip);
548         if (rval < 0) {
549                 dev_err(&client->dev, "fail : init chip\n");
550                 return rval;
551         }
552         /* backlight register */
553         rval = lm3630a_backlight_register(pchip);
554         if (rval < 0) {
555                 dev_err(&client->dev, "fail : backlight register.\n");
556                 return rval;
557         }
558         /* pwm */
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                         return dev_err_probe(&client->dev, PTR_ERR(pchip->pwmd),
563                                              "fail : get pwm device\n");
564
565                 pwm_init_state(pchip->pwmd, &pchip->pwmd_state);
566         }
567
568         /* interrupt enable  : irq 0 is not allowed */
569         pchip->irq = client->irq;
570         if (pchip->irq) {
571                 rval = lm3630a_intr_config(pchip);
572                 if (rval < 0)
573                         return rval;
574         }
575         dev_info(&client->dev, "LM3630A backlight register OK.\n");
576         return 0;
577 }
578
579 static void lm3630a_remove(struct i2c_client *client)
580 {
581         int rval;
582         struct lm3630a_chip *pchip = i2c_get_clientdata(client);
583
584         rval = lm3630a_write(pchip, REG_BRT_A, 0);
585         if (rval < 0)
586                 dev_err(pchip->dev, "i2c failed to access register\n");
587
588         rval = lm3630a_write(pchip, REG_BRT_B, 0);
589         if (rval < 0)
590                 dev_err(pchip->dev, "i2c failed to access register\n");
591
592         if (pchip->irq) {
593                 free_irq(pchip->irq, pchip);
594                 destroy_workqueue(pchip->irqthread);
595         }
596 }
597
598 static const struct i2c_device_id lm3630a_id[] = {
599         { LM3630A_NAME },
600         {}
601 };
602
603 MODULE_DEVICE_TABLE(i2c, lm3630a_id);
604
605 static const struct of_device_id lm3630a_match_table[] = {
606         { .compatible = "ti,lm3630a", },
607         { },
608 };
609
610 MODULE_DEVICE_TABLE(of, lm3630a_match_table);
611
612 static struct i2c_driver lm3630a_i2c_driver = {
613         .driver = {
614                    .name = LM3630A_NAME,
615                    .of_match_table = lm3630a_match_table,
616                    },
617         .probe = lm3630a_probe,
618         .remove = lm3630a_remove,
619         .id_table = lm3630a_id,
620 };
621
622 module_i2c_driver(lm3630a_i2c_driver);
623
624 MODULE_DESCRIPTION("Texas Instruments Backlight driver for LM3630A");
625 MODULE_AUTHOR("Daniel Jeong <[email protected]>");
626 MODULE_AUTHOR("LDD MLP <[email protected]>");
627 MODULE_LICENSE("GPL v2");
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