xref: /linux/drivers/video/backlight/adp8870_bl.c (revision 22d55f02b8922a097cd4be1e2f131dfa7ef65901)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Backlight driver for Analog Devices ADP8870 Backlight Devices
4  *
5  * Copyright 2009-2011 Analog Devices Inc.
6  */
7 
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/errno.h>
11 #include <linux/pm.h>
12 #include <linux/platform_device.h>
13 #include <linux/i2c.h>
14 #include <linux/fb.h>
15 #include <linux/backlight.h>
16 #include <linux/leds.h>
17 #include <linux/workqueue.h>
18 #include <linux/slab.h>
19 
20 #include <linux/platform_data/adp8870.h>
21 #define ADP8870_EXT_FEATURES
22 #define ADP8870_USE_LEDS
23 
24 
25 #define ADP8870_MFDVID	0x00  /* Manufacturer and device ID */
26 #define ADP8870_MDCR	0x01  /* Device mode and status */
27 #define ADP8870_INT_STAT 0x02  /* Interrupts status */
28 #define ADP8870_INT_EN	0x03  /* Interrupts enable */
29 #define ADP8870_CFGR	0x04  /* Configuration register */
30 #define ADP8870_BLSEL	0x05  /* Sink enable backlight or independent */
31 #define ADP8870_PWMLED	0x06  /* PWM Enable Selection Register */
32 #define ADP8870_BLOFF	0x07  /* Backlight off timeout */
33 #define ADP8870_BLDIM	0x08  /* Backlight dim timeout */
34 #define ADP8870_BLFR	0x09  /* Backlight fade in and out rates */
35 #define ADP8870_BLMX1	0x0A  /* Backlight (Brightness Level 1-daylight) maximum current */
36 #define ADP8870_BLDM1	0x0B  /* Backlight (Brightness Level 1-daylight) dim current */
37 #define ADP8870_BLMX2	0x0C  /* Backlight (Brightness Level 2-bright) maximum current */
38 #define ADP8870_BLDM2	0x0D  /* Backlight (Brightness Level 2-bright) dim current */
39 #define ADP8870_BLMX3	0x0E  /* Backlight (Brightness Level 3-office) maximum current */
40 #define ADP8870_BLDM3	0x0F  /* Backlight (Brightness Level 3-office) dim current */
41 #define ADP8870_BLMX4	0x10  /* Backlight (Brightness Level 4-indoor) maximum current */
42 #define ADP8870_BLDM4	0x11  /* Backlight (Brightness Level 4-indoor) dim current */
43 #define ADP8870_BLMX5	0x12  /* Backlight (Brightness Level 5-dark) maximum current */
44 #define ADP8870_BLDM5	0x13  /* Backlight (Brightness Level 5-dark) dim current */
45 #define ADP8870_ISCLAW	0x1A  /* Independent sink current fade law register */
46 #define ADP8870_ISCC	0x1B  /* Independent sink current control register */
47 #define ADP8870_ISCT1	0x1C  /* Independent Sink Current Timer Register LED[7:5] */
48 #define ADP8870_ISCT2	0x1D  /* Independent Sink Current Timer Register LED[4:1] */
49 #define ADP8870_ISCF	0x1E  /* Independent sink current fade register */
50 #define ADP8870_ISC1	0x1F  /* Independent Sink Current LED1 */
51 #define ADP8870_ISC2	0x20  /* Independent Sink Current LED2 */
52 #define ADP8870_ISC3	0x21  /* Independent Sink Current LED3 */
53 #define ADP8870_ISC4	0x22  /* Independent Sink Current LED4 */
54 #define ADP8870_ISC5	0x23  /* Independent Sink Current LED5 */
55 #define ADP8870_ISC6	0x24  /* Independent Sink Current LED6 */
56 #define ADP8870_ISC7	0x25  /* Independent Sink Current LED7 (Brightness Level 1-daylight) */
57 #define ADP8870_ISC7_L2	0x26  /* Independent Sink Current LED7 (Brightness Level 2-bright) */
58 #define ADP8870_ISC7_L3	0x27  /* Independent Sink Current LED7 (Brightness Level 3-office) */
59 #define ADP8870_ISC7_L4	0x28  /* Independent Sink Current LED7 (Brightness Level 4-indoor) */
60 #define ADP8870_ISC7_L5	0x29  /* Independent Sink Current LED7 (Brightness Level 5-dark) */
61 #define ADP8870_CMP_CTL	0x2D  /* ALS Comparator Control Register */
62 #define ADP8870_ALS1_EN	0x2E  /* Main ALS comparator level enable */
63 #define ADP8870_ALS2_EN	0x2F  /* Second ALS comparator level enable */
64 #define ADP8870_ALS1_STAT 0x30  /* Main ALS Comparator Status Register */
65 #define ADP8870_ALS2_STAT 0x31  /* Second ALS Comparator Status Register */
66 #define ADP8870_L2TRP	0x32  /* L2 comparator reference */
67 #define ADP8870_L2HYS	0x33  /* L2 hysteresis */
68 #define ADP8870_L3TRP	0x34  /* L3 comparator reference */
69 #define ADP8870_L3HYS	0x35  /* L3 hysteresis */
70 #define ADP8870_L4TRP	0x36  /* L4 comparator reference */
71 #define ADP8870_L4HYS	0x37  /* L4 hysteresis */
72 #define ADP8870_L5TRP	0x38  /* L5 comparator reference */
73 #define ADP8870_L5HYS	0x39  /* L5 hysteresis */
74 #define ADP8870_PH1LEVL	0x40  /* First phototransistor ambient light level-low byte register */
75 #define ADP8870_PH1LEVH	0x41  /* First phototransistor ambient light level-high byte register */
76 #define ADP8870_PH2LEVL	0x42  /* Second phototransistor ambient light level-low byte register */
77 #define ADP8870_PH2LEVH	0x43  /* Second phototransistor ambient light level-high byte register */
78 
79 #define ADP8870_MANUFID		0x3  /* Analog Devices AD8870 Manufacturer and device ID */
80 #define ADP8870_DEVID(x)	((x) & 0xF)
81 #define ADP8870_MANID(x)	((x) >> 4)
82 
83 /* MDCR Device mode and status */
84 #define D7ALSEN			(1 << 7)
85 #define INT_CFG			(1 << 6)
86 #define NSTBY			(1 << 5)
87 #define DIM_EN			(1 << 4)
88 #define GDWN_DIS		(1 << 3)
89 #define SIS_EN			(1 << 2)
90 #define CMP_AUTOEN		(1 << 1)
91 #define BLEN			(1 << 0)
92 
93 /* ADP8870_ALS1_EN Main ALS comparator level enable */
94 #define L5_EN			(1 << 3)
95 #define L4_EN			(1 << 2)
96 #define L3_EN			(1 << 1)
97 #define L2_EN			(1 << 0)
98 
99 #define CFGR_BLV_SHIFT		3
100 #define CFGR_BLV_MASK		0x7
101 #define ADP8870_FLAG_LED_MASK	0xFF
102 
103 #define FADE_VAL(in, out)	((0xF & (in)) | ((0xF & (out)) << 4))
104 #define BL_CFGR_VAL(law, blv)	((((blv) & CFGR_BLV_MASK) << CFGR_BLV_SHIFT) | ((0x3 & (law)) << 1))
105 #define ALS_CMPR_CFG_VAL(filt)	((0x7 & (filt)) << 1)
106 
107 struct adp8870_bl {
108 	struct i2c_client *client;
109 	struct backlight_device *bl;
110 	struct adp8870_led *led;
111 	struct adp8870_backlight_platform_data *pdata;
112 	struct mutex lock;
113 	unsigned long cached_daylight_max;
114 	int id;
115 	int revid;
116 	int current_brightness;
117 };
118 
119 struct adp8870_led {
120 	struct led_classdev	cdev;
121 	struct work_struct	work;
122 	struct i2c_client	*client;
123 	enum led_brightness	new_brightness;
124 	int			id;
125 	int			flags;
126 };
127 
128 static int adp8870_read(struct i2c_client *client, int reg, uint8_t *val)
129 {
130 	int ret;
131 
132 	ret = i2c_smbus_read_byte_data(client, reg);
133 	if (ret < 0) {
134 		dev_err(&client->dev, "failed reading at 0x%02x\n", reg);
135 		return ret;
136 	}
137 
138 	*val = ret;
139 	return 0;
140 }
141 
142 
143 static int adp8870_write(struct i2c_client *client, u8 reg, u8 val)
144 {
145 	int ret = i2c_smbus_write_byte_data(client, reg, val);
146 
147 	if (ret)
148 		dev_err(&client->dev, "failed to write\n");
149 
150 	return ret;
151 }
152 
153 static int adp8870_set_bits(struct i2c_client *client, int reg, uint8_t bit_mask)
154 {
155 	struct adp8870_bl *data = i2c_get_clientdata(client);
156 	uint8_t reg_val;
157 	int ret;
158 
159 	mutex_lock(&data->lock);
160 
161 	ret = adp8870_read(client, reg, &reg_val);
162 
163 	if (!ret && ((reg_val & bit_mask) != bit_mask)) {
164 		reg_val |= bit_mask;
165 		ret = adp8870_write(client, reg, reg_val);
166 	}
167 
168 	mutex_unlock(&data->lock);
169 	return ret;
170 }
171 
172 static int adp8870_clr_bits(struct i2c_client *client, int reg, uint8_t bit_mask)
173 {
174 	struct adp8870_bl *data = i2c_get_clientdata(client);
175 	uint8_t reg_val;
176 	int ret;
177 
178 	mutex_lock(&data->lock);
179 
180 	ret = adp8870_read(client, reg, &reg_val);
181 
182 	if (!ret && (reg_val & bit_mask)) {
183 		reg_val &= ~bit_mask;
184 		ret = adp8870_write(client, reg, reg_val);
185 	}
186 
187 	mutex_unlock(&data->lock);
188 	return ret;
189 }
190 
191 /*
192  * Independent sink / LED
193  */
194 #if defined(ADP8870_USE_LEDS)
195 static void adp8870_led_work(struct work_struct *work)
196 {
197 	struct adp8870_led *led = container_of(work, struct adp8870_led, work);
198 
199 	adp8870_write(led->client, ADP8870_ISC1 + led->id - 1,
200 			 led->new_brightness >> 1);
201 }
202 
203 static void adp8870_led_set(struct led_classdev *led_cdev,
204 			   enum led_brightness value)
205 {
206 	struct adp8870_led *led;
207 
208 	led = container_of(led_cdev, struct adp8870_led, cdev);
209 	led->new_brightness = value;
210 	/*
211 	 * Use workqueue for IO since I2C operations can sleep.
212 	 */
213 	schedule_work(&led->work);
214 }
215 
216 static int adp8870_led_setup(struct adp8870_led *led)
217 {
218 	struct i2c_client *client = led->client;
219 	int ret = 0;
220 
221 	ret = adp8870_write(client, ADP8870_ISC1 + led->id - 1, 0);
222 	if (ret)
223 		return ret;
224 
225 	ret = adp8870_set_bits(client, ADP8870_ISCC, 1 << (led->id - 1));
226 	if (ret)
227 		return ret;
228 
229 	if (led->id > 4)
230 		ret = adp8870_set_bits(client, ADP8870_ISCT1,
231 				(led->flags & 0x3) << ((led->id - 5) * 2));
232 	else
233 		ret = adp8870_set_bits(client, ADP8870_ISCT2,
234 				(led->flags & 0x3) << ((led->id - 1) * 2));
235 
236 	return ret;
237 }
238 
239 static int adp8870_led_probe(struct i2c_client *client)
240 {
241 	struct adp8870_backlight_platform_data *pdata =
242 		dev_get_platdata(&client->dev);
243 	struct adp8870_bl *data = i2c_get_clientdata(client);
244 	struct adp8870_led *led, *led_dat;
245 	struct led_info *cur_led;
246 	int ret, i;
247 
248 	led = devm_kcalloc(&client->dev, pdata->num_leds, sizeof(*led),
249 				GFP_KERNEL);
250 	if (led == NULL)
251 		return -ENOMEM;
252 
253 	ret = adp8870_write(client, ADP8870_ISCLAW, pdata->led_fade_law);
254 	if (ret)
255 		return ret;
256 
257 	ret = adp8870_write(client, ADP8870_ISCT1,
258 			(pdata->led_on_time & 0x3) << 6);
259 	if (ret)
260 		return ret;
261 
262 	ret = adp8870_write(client, ADP8870_ISCF,
263 			FADE_VAL(pdata->led_fade_in, pdata->led_fade_out));
264 	if (ret)
265 		return ret;
266 
267 	for (i = 0; i < pdata->num_leds; ++i) {
268 		cur_led = &pdata->leds[i];
269 		led_dat = &led[i];
270 
271 		led_dat->id = cur_led->flags & ADP8870_FLAG_LED_MASK;
272 
273 		if (led_dat->id > 7 || led_dat->id < 1) {
274 			dev_err(&client->dev, "Invalid LED ID %d\n",
275 				led_dat->id);
276 			ret = -EINVAL;
277 			goto err;
278 		}
279 
280 		if (pdata->bl_led_assign & (1 << (led_dat->id - 1))) {
281 			dev_err(&client->dev, "LED %d used by Backlight\n",
282 				led_dat->id);
283 			ret = -EBUSY;
284 			goto err;
285 		}
286 
287 		led_dat->cdev.name = cur_led->name;
288 		led_dat->cdev.default_trigger = cur_led->default_trigger;
289 		led_dat->cdev.brightness_set = adp8870_led_set;
290 		led_dat->cdev.brightness = LED_OFF;
291 		led_dat->flags = cur_led->flags >> FLAG_OFFT_SHIFT;
292 		led_dat->client = client;
293 		led_dat->new_brightness = LED_OFF;
294 		INIT_WORK(&led_dat->work, adp8870_led_work);
295 
296 		ret = led_classdev_register(&client->dev, &led_dat->cdev);
297 		if (ret) {
298 			dev_err(&client->dev, "failed to register LED %d\n",
299 				led_dat->id);
300 			goto err;
301 		}
302 
303 		ret = adp8870_led_setup(led_dat);
304 		if (ret) {
305 			dev_err(&client->dev, "failed to write\n");
306 			i++;
307 			goto err;
308 		}
309 	}
310 
311 	data->led = led;
312 
313 	return 0;
314 
315  err:
316 	for (i = i - 1; i >= 0; --i) {
317 		led_classdev_unregister(&led[i].cdev);
318 		cancel_work_sync(&led[i].work);
319 	}
320 
321 	return ret;
322 }
323 
324 static int adp8870_led_remove(struct i2c_client *client)
325 {
326 	struct adp8870_backlight_platform_data *pdata =
327 		dev_get_platdata(&client->dev);
328 	struct adp8870_bl *data = i2c_get_clientdata(client);
329 	int i;
330 
331 	for (i = 0; i < pdata->num_leds; i++) {
332 		led_classdev_unregister(&data->led[i].cdev);
333 		cancel_work_sync(&data->led[i].work);
334 	}
335 
336 	return 0;
337 }
338 #else
339 static int adp8870_led_probe(struct i2c_client *client)
340 {
341 	return 0;
342 }
343 
344 static int adp8870_led_remove(struct i2c_client *client)
345 {
346 	return 0;
347 }
348 #endif
349 
350 static int adp8870_bl_set(struct backlight_device *bl, int brightness)
351 {
352 	struct adp8870_bl *data = bl_get_data(bl);
353 	struct i2c_client *client = data->client;
354 	int ret = 0;
355 
356 	if (data->pdata->en_ambl_sens) {
357 		if ((brightness > 0) && (brightness < ADP8870_MAX_BRIGHTNESS)) {
358 			/* Disable Ambient Light auto adjust */
359 			ret = adp8870_clr_bits(client, ADP8870_MDCR,
360 					CMP_AUTOEN);
361 			if (ret)
362 				return ret;
363 			ret = adp8870_write(client, ADP8870_BLMX1, brightness);
364 			if (ret)
365 				return ret;
366 		} else {
367 			/*
368 			 * MAX_BRIGHTNESS -> Enable Ambient Light auto adjust
369 			 * restore daylight l1 sysfs brightness
370 			 */
371 			ret = adp8870_write(client, ADP8870_BLMX1,
372 					 data->cached_daylight_max);
373 			if (ret)
374 				return ret;
375 
376 			ret = adp8870_set_bits(client, ADP8870_MDCR,
377 					 CMP_AUTOEN);
378 			if (ret)
379 				return ret;
380 		}
381 	} else {
382 		ret = adp8870_write(client, ADP8870_BLMX1, brightness);
383 		if (ret)
384 			return ret;
385 	}
386 
387 	if (data->current_brightness && brightness == 0)
388 		ret = adp8870_set_bits(client,
389 				ADP8870_MDCR, DIM_EN);
390 	else if (data->current_brightness == 0 && brightness)
391 		ret = adp8870_clr_bits(client,
392 				ADP8870_MDCR, DIM_EN);
393 
394 	if (!ret)
395 		data->current_brightness = brightness;
396 
397 	return ret;
398 }
399 
400 static int adp8870_bl_update_status(struct backlight_device *bl)
401 {
402 	int brightness = bl->props.brightness;
403 
404 	if (bl->props.power != FB_BLANK_UNBLANK)
405 		brightness = 0;
406 
407 	if (bl->props.fb_blank != FB_BLANK_UNBLANK)
408 		brightness = 0;
409 
410 	return adp8870_bl_set(bl, brightness);
411 }
412 
413 static int adp8870_bl_get_brightness(struct backlight_device *bl)
414 {
415 	struct adp8870_bl *data = bl_get_data(bl);
416 
417 	return data->current_brightness;
418 }
419 
420 static const struct backlight_ops adp8870_bl_ops = {
421 	.update_status	= adp8870_bl_update_status,
422 	.get_brightness	= adp8870_bl_get_brightness,
423 };
424 
425 static int adp8870_bl_setup(struct backlight_device *bl)
426 {
427 	struct adp8870_bl *data = bl_get_data(bl);
428 	struct i2c_client *client = data->client;
429 	struct adp8870_backlight_platform_data *pdata = data->pdata;
430 	int ret = 0;
431 
432 	ret = adp8870_write(client, ADP8870_BLSEL, ~pdata->bl_led_assign);
433 	if (ret)
434 		return ret;
435 
436 	ret = adp8870_write(client, ADP8870_PWMLED, pdata->pwm_assign);
437 	if (ret)
438 		return ret;
439 
440 	ret = adp8870_write(client, ADP8870_BLMX1, pdata->l1_daylight_max);
441 	if (ret)
442 		return ret;
443 
444 	ret = adp8870_write(client, ADP8870_BLDM1, pdata->l1_daylight_dim);
445 	if (ret)
446 		return ret;
447 
448 	if (pdata->en_ambl_sens) {
449 		data->cached_daylight_max = pdata->l1_daylight_max;
450 		ret = adp8870_write(client, ADP8870_BLMX2,
451 						pdata->l2_bright_max);
452 		if (ret)
453 			return ret;
454 		ret = adp8870_write(client, ADP8870_BLDM2,
455 						pdata->l2_bright_dim);
456 		if (ret)
457 			return ret;
458 
459 		ret = adp8870_write(client, ADP8870_BLMX3,
460 						pdata->l3_office_max);
461 		if (ret)
462 			return ret;
463 		ret = adp8870_write(client, ADP8870_BLDM3,
464 						pdata->l3_office_dim);
465 		if (ret)
466 			return ret;
467 
468 		ret = adp8870_write(client, ADP8870_BLMX4,
469 						pdata->l4_indoor_max);
470 		if (ret)
471 			return ret;
472 
473 		ret = adp8870_write(client, ADP8870_BLDM4,
474 						pdata->l4_indor_dim);
475 		if (ret)
476 			return ret;
477 
478 		ret = adp8870_write(client, ADP8870_BLMX5,
479 						pdata->l5_dark_max);
480 		if (ret)
481 			return ret;
482 
483 		ret = adp8870_write(client, ADP8870_BLDM5,
484 						pdata->l5_dark_dim);
485 		if (ret)
486 			return ret;
487 
488 		ret = adp8870_write(client, ADP8870_L2TRP, pdata->l2_trip);
489 		if (ret)
490 			return ret;
491 
492 		ret = adp8870_write(client, ADP8870_L2HYS, pdata->l2_hyst);
493 		if (ret)
494 			return ret;
495 
496 		ret = adp8870_write(client, ADP8870_L3TRP, pdata->l3_trip);
497 		if (ret)
498 			return ret;
499 
500 		ret = adp8870_write(client, ADP8870_L3HYS, pdata->l3_hyst);
501 		if (ret)
502 			return ret;
503 
504 		ret = adp8870_write(client, ADP8870_L4TRP, pdata->l4_trip);
505 		if (ret)
506 			return ret;
507 
508 		ret = adp8870_write(client, ADP8870_L4HYS, pdata->l4_hyst);
509 		if (ret)
510 			return ret;
511 
512 		ret = adp8870_write(client, ADP8870_L5TRP, pdata->l5_trip);
513 		if (ret)
514 			return ret;
515 
516 		ret = adp8870_write(client, ADP8870_L5HYS, pdata->l5_hyst);
517 		if (ret)
518 			return ret;
519 
520 		ret = adp8870_write(client, ADP8870_ALS1_EN, L5_EN | L4_EN |
521 						L3_EN | L2_EN);
522 		if (ret)
523 			return ret;
524 
525 		ret = adp8870_write(client, ADP8870_CMP_CTL,
526 			ALS_CMPR_CFG_VAL(pdata->abml_filt));
527 		if (ret)
528 			return ret;
529 	}
530 
531 	ret = adp8870_write(client, ADP8870_CFGR,
532 			BL_CFGR_VAL(pdata->bl_fade_law, 0));
533 	if (ret)
534 		return ret;
535 
536 	ret = adp8870_write(client, ADP8870_BLFR, FADE_VAL(pdata->bl_fade_in,
537 			pdata->bl_fade_out));
538 	if (ret)
539 		return ret;
540 	/*
541 	 * ADP8870 Rev0 requires GDWN_DIS bit set
542 	 */
543 
544 	ret = adp8870_set_bits(client, ADP8870_MDCR, BLEN | DIM_EN | NSTBY |
545 			(data->revid == 0 ? GDWN_DIS : 0));
546 
547 	return ret;
548 }
549 
550 static ssize_t adp8870_show(struct device *dev, char *buf, int reg)
551 {
552 	struct adp8870_bl *data = dev_get_drvdata(dev);
553 	int error;
554 	uint8_t reg_val;
555 
556 	mutex_lock(&data->lock);
557 	error = adp8870_read(data->client, reg, &reg_val);
558 	mutex_unlock(&data->lock);
559 
560 	if (error < 0)
561 		return error;
562 
563 	return sprintf(buf, "%u\n", reg_val);
564 }
565 
566 static ssize_t adp8870_store(struct device *dev, const char *buf,
567 			 size_t count, int reg)
568 {
569 	struct adp8870_bl *data = dev_get_drvdata(dev);
570 	unsigned long val;
571 	int ret;
572 
573 	ret = kstrtoul(buf, 10, &val);
574 	if (ret)
575 		return ret;
576 
577 	mutex_lock(&data->lock);
578 	adp8870_write(data->client, reg, val);
579 	mutex_unlock(&data->lock);
580 
581 	return count;
582 }
583 
584 static ssize_t adp8870_bl_l5_dark_max_show(struct device *dev,
585 		struct device_attribute *attr, char *buf)
586 {
587 	return adp8870_show(dev, buf, ADP8870_BLMX5);
588 }
589 
590 static ssize_t adp8870_bl_l5_dark_max_store(struct device *dev,
591 		struct device_attribute *attr, const char *buf, size_t count)
592 {
593 	return adp8870_store(dev, buf, count, ADP8870_BLMX5);
594 }
595 static DEVICE_ATTR(l5_dark_max, 0664, adp8870_bl_l5_dark_max_show,
596 			adp8870_bl_l5_dark_max_store);
597 
598 
599 static ssize_t adp8870_bl_l4_indoor_max_show(struct device *dev,
600 		struct device_attribute *attr, char *buf)
601 {
602 	return adp8870_show(dev, buf, ADP8870_BLMX4);
603 }
604 
605 static ssize_t adp8870_bl_l4_indoor_max_store(struct device *dev,
606 		struct device_attribute *attr, const char *buf, size_t count)
607 {
608 	return adp8870_store(dev, buf, count, ADP8870_BLMX4);
609 }
610 static DEVICE_ATTR(l4_indoor_max, 0664, adp8870_bl_l4_indoor_max_show,
611 			adp8870_bl_l4_indoor_max_store);
612 
613 
614 static ssize_t adp8870_bl_l3_office_max_show(struct device *dev,
615 				     struct device_attribute *attr, char *buf)
616 {
617 	return adp8870_show(dev, buf, ADP8870_BLMX3);
618 }
619 
620 static ssize_t adp8870_bl_l3_office_max_store(struct device *dev,
621 		struct device_attribute *attr, const char *buf, size_t count)
622 {
623 	return adp8870_store(dev, buf, count, ADP8870_BLMX3);
624 }
625 
626 static DEVICE_ATTR(l3_office_max, 0664, adp8870_bl_l3_office_max_show,
627 			adp8870_bl_l3_office_max_store);
628 
629 static ssize_t adp8870_bl_l2_bright_max_show(struct device *dev,
630 		struct device_attribute *attr, char *buf)
631 {
632 	return adp8870_show(dev, buf, ADP8870_BLMX2);
633 }
634 
635 static ssize_t adp8870_bl_l2_bright_max_store(struct device *dev,
636 		struct device_attribute *attr, const char *buf, size_t count)
637 {
638 	return adp8870_store(dev, buf, count, ADP8870_BLMX2);
639 }
640 static DEVICE_ATTR(l2_bright_max, 0664, adp8870_bl_l2_bright_max_show,
641 			adp8870_bl_l2_bright_max_store);
642 
643 static ssize_t adp8870_bl_l1_daylight_max_show(struct device *dev,
644 			struct device_attribute *attr, char *buf)
645 {
646 	return adp8870_show(dev, buf, ADP8870_BLMX1);
647 }
648 
649 static ssize_t adp8870_bl_l1_daylight_max_store(struct device *dev,
650 		struct device_attribute *attr, const char *buf, size_t count)
651 {
652 	struct adp8870_bl *data = dev_get_drvdata(dev);
653 	int ret = kstrtoul(buf, 10, &data->cached_daylight_max);
654 
655 	if (ret)
656 		return ret;
657 
658 	return adp8870_store(dev, buf, count, ADP8870_BLMX1);
659 }
660 static DEVICE_ATTR(l1_daylight_max, 0664, adp8870_bl_l1_daylight_max_show,
661 			adp8870_bl_l1_daylight_max_store);
662 
663 static ssize_t adp8870_bl_l5_dark_dim_show(struct device *dev,
664 			struct device_attribute *attr, char *buf)
665 {
666 	return adp8870_show(dev, buf, ADP8870_BLDM5);
667 }
668 
669 static ssize_t adp8870_bl_l5_dark_dim_store(struct device *dev,
670 				     struct device_attribute *attr,
671 				     const char *buf, size_t count)
672 {
673 	return adp8870_store(dev, buf, count, ADP8870_BLDM5);
674 }
675 static DEVICE_ATTR(l5_dark_dim, 0664, adp8870_bl_l5_dark_dim_show,
676 			adp8870_bl_l5_dark_dim_store);
677 
678 static ssize_t adp8870_bl_l4_indoor_dim_show(struct device *dev,
679 			struct device_attribute *attr, char *buf)
680 {
681 	return adp8870_show(dev, buf, ADP8870_BLDM4);
682 }
683 
684 static ssize_t adp8870_bl_l4_indoor_dim_store(struct device *dev,
685 				     struct device_attribute *attr,
686 				     const char *buf, size_t count)
687 {
688 	return adp8870_store(dev, buf, count, ADP8870_BLDM4);
689 }
690 static DEVICE_ATTR(l4_indoor_dim, 0664, adp8870_bl_l4_indoor_dim_show,
691 			adp8870_bl_l4_indoor_dim_store);
692 
693 
694 static ssize_t adp8870_bl_l3_office_dim_show(struct device *dev,
695 			struct device_attribute *attr, char *buf)
696 {
697 	return adp8870_show(dev, buf, ADP8870_BLDM3);
698 }
699 
700 static ssize_t adp8870_bl_l3_office_dim_store(struct device *dev,
701 				     struct device_attribute *attr,
702 				     const char *buf, size_t count)
703 {
704 	return adp8870_store(dev, buf, count, ADP8870_BLDM3);
705 }
706 static DEVICE_ATTR(l3_office_dim, 0664, adp8870_bl_l3_office_dim_show,
707 			adp8870_bl_l3_office_dim_store);
708 
709 static ssize_t adp8870_bl_l2_bright_dim_show(struct device *dev,
710 			struct device_attribute *attr, char *buf)
711 {
712 	return adp8870_show(dev, buf, ADP8870_BLDM2);
713 }
714 
715 static ssize_t adp8870_bl_l2_bright_dim_store(struct device *dev,
716 				     struct device_attribute *attr,
717 				     const char *buf, size_t count)
718 {
719 	return adp8870_store(dev, buf, count, ADP8870_BLDM2);
720 }
721 static DEVICE_ATTR(l2_bright_dim, 0664, adp8870_bl_l2_bright_dim_show,
722 			adp8870_bl_l2_bright_dim_store);
723 
724 static ssize_t adp8870_bl_l1_daylight_dim_show(struct device *dev,
725 				     struct device_attribute *attr, char *buf)
726 {
727 	return adp8870_show(dev, buf, ADP8870_BLDM1);
728 }
729 
730 static ssize_t adp8870_bl_l1_daylight_dim_store(struct device *dev,
731 				     struct device_attribute *attr,
732 				     const char *buf, size_t count)
733 {
734 	return adp8870_store(dev, buf, count, ADP8870_BLDM1);
735 }
736 static DEVICE_ATTR(l1_daylight_dim, 0664, adp8870_bl_l1_daylight_dim_show,
737 			adp8870_bl_l1_daylight_dim_store);
738 
739 #ifdef ADP8870_EXT_FEATURES
740 static ssize_t adp8870_bl_ambient_light_level_show(struct device *dev,
741 				     struct device_attribute *attr, char *buf)
742 {
743 	struct adp8870_bl *data = dev_get_drvdata(dev);
744 	int error;
745 	uint8_t reg_val;
746 	uint16_t ret_val;
747 
748 	mutex_lock(&data->lock);
749 	error = adp8870_read(data->client, ADP8870_PH1LEVL, &reg_val);
750 	if (error < 0) {
751 		mutex_unlock(&data->lock);
752 		return error;
753 	}
754 	ret_val = reg_val;
755 	error = adp8870_read(data->client, ADP8870_PH1LEVH, &reg_val);
756 	mutex_unlock(&data->lock);
757 
758 	if (error < 0)
759 		return error;
760 
761 	/* Return 13-bit conversion value for the first light sensor */
762 	ret_val += (reg_val & 0x1F) << 8;
763 
764 	return sprintf(buf, "%u\n", ret_val);
765 }
766 static DEVICE_ATTR(ambient_light_level, 0444,
767 		adp8870_bl_ambient_light_level_show, NULL);
768 
769 static ssize_t adp8870_bl_ambient_light_zone_show(struct device *dev,
770 				     struct device_attribute *attr, char *buf)
771 {
772 	struct adp8870_bl *data = dev_get_drvdata(dev);
773 	int error;
774 	uint8_t reg_val;
775 
776 	mutex_lock(&data->lock);
777 	error = adp8870_read(data->client, ADP8870_CFGR, &reg_val);
778 	mutex_unlock(&data->lock);
779 
780 	if (error < 0)
781 		return error;
782 
783 	return sprintf(buf, "%u\n",
784 		((reg_val >> CFGR_BLV_SHIFT) & CFGR_BLV_MASK) + 1);
785 }
786 
787 static ssize_t adp8870_bl_ambient_light_zone_store(struct device *dev,
788 				     struct device_attribute *attr,
789 				     const char *buf, size_t count)
790 {
791 	struct adp8870_bl *data = dev_get_drvdata(dev);
792 	unsigned long val;
793 	uint8_t reg_val;
794 	int ret;
795 
796 	ret = kstrtoul(buf, 10, &val);
797 	if (ret)
798 		return ret;
799 
800 	if (val == 0) {
801 		/* Enable automatic ambient light sensing */
802 		adp8870_set_bits(data->client, ADP8870_MDCR, CMP_AUTOEN);
803 	} else if ((val > 0) && (val < 6)) {
804 		/* Disable automatic ambient light sensing */
805 		adp8870_clr_bits(data->client, ADP8870_MDCR, CMP_AUTOEN);
806 
807 		/* Set user supplied ambient light zone */
808 		mutex_lock(&data->lock);
809 		ret = adp8870_read(data->client, ADP8870_CFGR, &reg_val);
810 		if (!ret) {
811 			reg_val &= ~(CFGR_BLV_MASK << CFGR_BLV_SHIFT);
812 			reg_val |= (val - 1) << CFGR_BLV_SHIFT;
813 			adp8870_write(data->client, ADP8870_CFGR, reg_val);
814 		}
815 		mutex_unlock(&data->lock);
816 	}
817 
818 	return count;
819 }
820 static DEVICE_ATTR(ambient_light_zone, 0664,
821 		adp8870_bl_ambient_light_zone_show,
822 		adp8870_bl_ambient_light_zone_store);
823 #endif
824 
825 static struct attribute *adp8870_bl_attributes[] = {
826 	&dev_attr_l5_dark_max.attr,
827 	&dev_attr_l5_dark_dim.attr,
828 	&dev_attr_l4_indoor_max.attr,
829 	&dev_attr_l4_indoor_dim.attr,
830 	&dev_attr_l3_office_max.attr,
831 	&dev_attr_l3_office_dim.attr,
832 	&dev_attr_l2_bright_max.attr,
833 	&dev_attr_l2_bright_dim.attr,
834 	&dev_attr_l1_daylight_max.attr,
835 	&dev_attr_l1_daylight_dim.attr,
836 #ifdef ADP8870_EXT_FEATURES
837 	&dev_attr_ambient_light_level.attr,
838 	&dev_attr_ambient_light_zone.attr,
839 #endif
840 	NULL
841 };
842 
843 static const struct attribute_group adp8870_bl_attr_group = {
844 	.attrs = adp8870_bl_attributes,
845 };
846 
847 static int adp8870_probe(struct i2c_client *client,
848 					const struct i2c_device_id *id)
849 {
850 	struct backlight_properties props;
851 	struct backlight_device *bl;
852 	struct adp8870_bl *data;
853 	struct adp8870_backlight_platform_data *pdata =
854 		dev_get_platdata(&client->dev);
855 	uint8_t reg_val;
856 	int ret;
857 
858 	if (!i2c_check_functionality(client->adapter,
859 					I2C_FUNC_SMBUS_BYTE_DATA)) {
860 		dev_err(&client->dev, "SMBUS Byte Data not Supported\n");
861 		return -EIO;
862 	}
863 
864 	if (!pdata) {
865 		dev_err(&client->dev, "no platform data?\n");
866 		return -EINVAL;
867 	}
868 
869 	ret = adp8870_read(client, ADP8870_MFDVID, &reg_val);
870 	if (ret < 0)
871 		return -EIO;
872 
873 	if (ADP8870_MANID(reg_val) != ADP8870_MANUFID) {
874 		dev_err(&client->dev, "failed to probe\n");
875 		return -ENODEV;
876 	}
877 
878 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
879 	if (data == NULL)
880 		return -ENOMEM;
881 
882 	data->revid = ADP8870_DEVID(reg_val);
883 	data->client = client;
884 	data->pdata = pdata;
885 	data->id = id->driver_data;
886 	data->current_brightness = 0;
887 	i2c_set_clientdata(client, data);
888 
889 	mutex_init(&data->lock);
890 
891 	memset(&props, 0, sizeof(props));
892 	props.type = BACKLIGHT_RAW;
893 	props.max_brightness = props.brightness = ADP8870_MAX_BRIGHTNESS;
894 	bl = devm_backlight_device_register(&client->dev,
895 				dev_driver_string(&client->dev),
896 				&client->dev, data, &adp8870_bl_ops, &props);
897 	if (IS_ERR(bl)) {
898 		dev_err(&client->dev, "failed to register backlight\n");
899 		return PTR_ERR(bl);
900 	}
901 
902 	data->bl = bl;
903 
904 	if (pdata->en_ambl_sens) {
905 		ret = sysfs_create_group(&bl->dev.kobj,
906 			&adp8870_bl_attr_group);
907 		if (ret) {
908 			dev_err(&client->dev, "failed to register sysfs\n");
909 			return ret;
910 		}
911 	}
912 
913 	ret = adp8870_bl_setup(bl);
914 	if (ret) {
915 		ret = -EIO;
916 		goto out;
917 	}
918 
919 	backlight_update_status(bl);
920 
921 	dev_info(&client->dev, "Rev.%d Backlight\n", data->revid);
922 
923 	if (pdata->num_leds)
924 		adp8870_led_probe(client);
925 
926 	return 0;
927 
928 out:
929 	if (data->pdata->en_ambl_sens)
930 		sysfs_remove_group(&data->bl->dev.kobj,
931 			&adp8870_bl_attr_group);
932 
933 	return ret;
934 }
935 
936 static int adp8870_remove(struct i2c_client *client)
937 {
938 	struct adp8870_bl *data = i2c_get_clientdata(client);
939 
940 	adp8870_clr_bits(client, ADP8870_MDCR, NSTBY);
941 
942 	if (data->led)
943 		adp8870_led_remove(client);
944 
945 	if (data->pdata->en_ambl_sens)
946 		sysfs_remove_group(&data->bl->dev.kobj,
947 			&adp8870_bl_attr_group);
948 
949 	return 0;
950 }
951 
952 #ifdef CONFIG_PM_SLEEP
953 static int adp8870_i2c_suspend(struct device *dev)
954 {
955 	struct i2c_client *client = to_i2c_client(dev);
956 
957 	adp8870_clr_bits(client, ADP8870_MDCR, NSTBY);
958 
959 	return 0;
960 }
961 
962 static int adp8870_i2c_resume(struct device *dev)
963 {
964 	struct i2c_client *client = to_i2c_client(dev);
965 
966 	adp8870_set_bits(client, ADP8870_MDCR, NSTBY | BLEN);
967 
968 	return 0;
969 }
970 #endif
971 
972 static SIMPLE_DEV_PM_OPS(adp8870_i2c_pm_ops, adp8870_i2c_suspend,
973 			adp8870_i2c_resume);
974 
975 static const struct i2c_device_id adp8870_id[] = {
976 	{ "adp8870", 0 },
977 	{ }
978 };
979 MODULE_DEVICE_TABLE(i2c, adp8870_id);
980 
981 static struct i2c_driver adp8870_driver = {
982 	.driver = {
983 		.name	= KBUILD_MODNAME,
984 		.pm	= &adp8870_i2c_pm_ops,
985 	},
986 	.probe    = adp8870_probe,
987 	.remove   = adp8870_remove,
988 	.id_table = adp8870_id,
989 };
990 
991 module_i2c_driver(adp8870_driver);
992 
993 MODULE_LICENSE("GPL v2");
994 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
995 MODULE_DESCRIPTION("ADP8870 Backlight driver");
996