1 /*
2  * Backlight driver for Analog Devices ADP8870 Backlight Devices
3  *
4  * Copyright 2009-2011 Analog Devices Inc.
5  *
6  * Licensed under the GPL-2 or later.
7  */
8 
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/errno.h>
12 #include <linux/pm.h>
13 #include <linux/platform_device.h>
14 #include <linux/i2c.h>
15 #include <linux/fb.h>
16 #include <linux/backlight.h>
17 #include <linux/leds.h>
18 #include <linux/workqueue.h>
19 #include <linux/slab.h>
20 
21 #include <linux/i2c/adp8870.h>
22 #define ADP8870_EXT_FEATURES
23 #define ADP8870_USE_LEDS
24 
25 
26 #define ADP8870_MFDVID	0x00  /* Manufacturer and device ID */
27 #define ADP8870_MDCR	0x01  /* Device mode and status */
28 #define ADP8870_INT_STAT 0x02  /* Interrupts status */
29 #define ADP8870_INT_EN	0x03  /* Interrupts enable */
30 #define ADP8870_CFGR	0x04  /* Configuration register */
31 #define ADP8870_BLSEL	0x05  /* Sink enable backlight or independent */
32 #define ADP8870_PWMLED	0x06  /* PWM Enable Selection Register */
33 #define ADP8870_BLOFF	0x07  /* Backlight off timeout */
34 #define ADP8870_BLDIM	0x08  /* Backlight dim timeout */
35 #define ADP8870_BLFR	0x09  /* Backlight fade in and out rates */
36 #define ADP8870_BLMX1	0x0A  /* Backlight (Brightness Level 1-daylight) maximum current */
37 #define ADP8870_BLDM1	0x0B  /* Backlight (Brightness Level 1-daylight) dim current */
38 #define ADP8870_BLMX2	0x0C  /* Backlight (Brightness Level 2-bright) maximum current */
39 #define ADP8870_BLDM2	0x0D  /* Backlight (Brightness Level 2-bright) dim current */
40 #define ADP8870_BLMX3	0x0E  /* Backlight (Brightness Level 3-office) maximum current */
41 #define ADP8870_BLDM3	0x0F  /* Backlight (Brightness Level 3-office) dim current */
42 #define ADP8870_BLMX4	0x10  /* Backlight (Brightness Level 4-indoor) maximum current */
43 #define ADP8870_BLDM4	0x11  /* Backlight (Brightness Level 4-indoor) dim current */
44 #define ADP8870_BLMX5	0x12  /* Backlight (Brightness Level 5-dark) maximum current */
45 #define ADP8870_BLDM5	0x13  /* Backlight (Brightness Level 5-dark) dim current */
46 #define ADP8870_ISCLAW	0x1A  /* Independent sink current fade law register */
47 #define ADP8870_ISCC	0x1B  /* Independent sink current control register */
48 #define ADP8870_ISCT1	0x1C  /* Independent Sink Current Timer Register LED[7:5] */
49 #define ADP8870_ISCT2	0x1D  /* Independent Sink Current Timer Register LED[4:1] */
50 #define ADP8870_ISCF	0x1E  /* Independent sink current fade register */
51 #define ADP8870_ISC1	0x1F  /* Independent Sink Current LED1 */
52 #define ADP8870_ISC2	0x20  /* Independent Sink Current LED2 */
53 #define ADP8870_ISC3	0x21  /* Independent Sink Current LED3 */
54 #define ADP8870_ISC4	0x22  /* Independent Sink Current LED4 */
55 #define ADP8870_ISC5	0x23  /* Independent Sink Current LED5 */
56 #define ADP8870_ISC6	0x24  /* Independent Sink Current LED6 */
57 #define ADP8870_ISC7	0x25  /* Independent Sink Current LED7 (Brightness Level 1-daylight) */
58 #define ADP8870_ISC7_L2	0x26  /* Independent Sink Current LED7 (Brightness Level 2-bright) */
59 #define ADP8870_ISC7_L3	0x27  /* Independent Sink Current LED7 (Brightness Level 3-office) */
60 #define ADP8870_ISC7_L4	0x28  /* Independent Sink Current LED7 (Brightness Level 4-indoor) */
61 #define ADP8870_ISC7_L5	0x29  /* Independent Sink Current LED7 (Brightness Level 5-dark) */
62 #define ADP8870_CMP_CTL	0x2D  /* ALS Comparator Control Register */
63 #define ADP8870_ALS1_EN	0x2E  /* Main ALS comparator level enable */
64 #define ADP8870_ALS2_EN	0x2F  /* Second ALS comparator level enable */
65 #define ADP8870_ALS1_STAT 0x30  /* Main ALS Comparator Status Register */
66 #define ADP8870_ALS2_STAT 0x31  /* Second ALS Comparator Status Register */
67 #define ADP8870_L2TRP	0x32  /* L2 comparator reference */
68 #define ADP8870_L2HYS	0x33  /* L2 hysteresis */
69 #define ADP8870_L3TRP	0x34  /* L3 comparator reference */
70 #define ADP8870_L3HYS	0x35  /* L3 hysteresis */
71 #define ADP8870_L4TRP	0x36  /* L4 comparator reference */
72 #define ADP8870_L4HYS	0x37  /* L4 hysteresis */
73 #define ADP8870_L5TRP	0x38  /* L5 comparator reference */
74 #define ADP8870_L5HYS	0x39  /* L5 hysteresis */
75 #define ADP8870_PH1LEVL	0x40  /* First phototransistor ambient light level-low byte register */
76 #define ADP8870_PH1LEVH	0x41  /* First phototransistor ambient light level-high byte register */
77 #define ADP8870_PH2LEVL	0x42  /* Second phototransistor ambient light level-low byte register */
78 #define ADP8870_PH2LEVH	0x43  /* Second phototransistor ambient light level-high byte register */
79 
80 #define ADP8870_MANUFID		0x3  /* Analog Devices AD8870 Manufacturer and device ID */
81 #define ADP8870_DEVID(x)	((x) & 0xF)
82 #define ADP8870_MANID(x)	((x) >> 4)
83 
84 /* MDCR Device mode and status */
85 #define D7ALSEN			(1 << 7)
86 #define INT_CFG			(1 << 6)
87 #define NSTBY			(1 << 5)
88 #define DIM_EN			(1 << 4)
89 #define GDWN_DIS		(1 << 3)
90 #define SIS_EN			(1 << 2)
91 #define CMP_AUTOEN		(1 << 1)
92 #define BLEN			(1 << 0)
93 
94 /* ADP8870_ALS1_EN Main ALS comparator level enable */
95 #define L5_EN			(1 << 3)
96 #define L4_EN			(1 << 2)
97 #define L3_EN			(1 << 1)
98 #define L2_EN			(1 << 0)
99 
100 #define CFGR_BLV_SHIFT		3
101 #define CFGR_BLV_MASK		0x7
102 #define ADP8870_FLAG_LED_MASK	0xFF
103 
104 #define FADE_VAL(in, out)	((0xF & (in)) | ((0xF & (out)) << 4))
105 #define BL_CFGR_VAL(law, blv)	((((blv) & CFGR_BLV_MASK) << CFGR_BLV_SHIFT) | ((0x3 & (law)) << 1))
106 #define ALS_CMPR_CFG_VAL(filt)	((0x7 & (filt)) << 1)
107 
108 struct adp8870_bl {
109 	struct i2c_client *client;
110 	struct backlight_device *bl;
111 	struct adp8870_led *led;
112 	struct adp8870_backlight_platform_data *pdata;
113 	struct mutex lock;
114 	unsigned long cached_daylight_max;
115 	int id;
116 	int revid;
117 	int current_brightness;
118 };
119 
120 struct adp8870_led {
121 	struct led_classdev	cdev;
122 	struct work_struct	work;
123 	struct i2c_client	*client;
124 	enum led_brightness	new_brightness;
125 	int			id;
126 	int			flags;
127 };
128 
129 static int adp8870_read(struct i2c_client *client, int reg, uint8_t *val)
130 {
131 	int ret;
132 
133 	ret = i2c_smbus_read_byte_data(client, reg);
134 	if (ret < 0) {
135 		dev_err(&client->dev, "failed reading at 0x%02x\n", reg);
136 		return ret;
137 	}
138 
139 	*val = ret;
140 	return 0;
141 }
142 
143 
144 static int adp8870_write(struct i2c_client *client, u8 reg, u8 val)
145 {
146 	int ret = i2c_smbus_write_byte_data(client, reg, val);
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 	adp8870_write(led->client, ADP8870_ISC1 + led->id - 1,
199 			 led->new_brightness >> 1);
200 }
201 
202 static void adp8870_led_set(struct led_classdev *led_cdev,
203 			   enum led_brightness value)
204 {
205 	struct adp8870_led *led;
206 
207 	led = container_of(led_cdev, struct adp8870_led, cdev);
208 	led->new_brightness = value;
209 	/*
210 	 * Use workqueue for IO since I2C operations can sleep.
211 	 */
212 	schedule_work(&led->work);
213 }
214 
215 static int adp8870_led_setup(struct adp8870_led *led)
216 {
217 	struct i2c_client *client = led->client;
218 	int ret = 0;
219 
220 	ret = adp8870_write(client, ADP8870_ISC1 + led->id - 1, 0);
221 	if (ret)
222 		return ret;
223 
224 	ret = adp8870_set_bits(client, ADP8870_ISCC, 1 << (led->id - 1));
225 	if (ret)
226 		return ret;
227 
228 	if (led->id > 4)
229 		ret = adp8870_set_bits(client, ADP8870_ISCT1,
230 				(led->flags & 0x3) << ((led->id - 5) * 2));
231 	else
232 		ret = adp8870_set_bits(client, ADP8870_ISCT2,
233 				(led->flags & 0x3) << ((led->id - 1) * 2));
234 
235 	return ret;
236 }
237 
238 static int __devinit adp8870_led_probe(struct i2c_client *client)
239 {
240 	struct adp8870_backlight_platform_data *pdata =
241 		client->dev.platform_data;
242 	struct adp8870_bl *data = i2c_get_clientdata(client);
243 	struct adp8870_led *led, *led_dat;
244 	struct led_info *cur_led;
245 	int ret, i;
246 
247 	led = devm_kzalloc(&client->dev, pdata->num_leds * sizeof(*led),
248 				GFP_KERNEL);
249 	if (led == NULL) {
250 		dev_err(&client->dev, "failed to alloc memory\n");
251 		return -ENOMEM;
252 	}
253 
254 	ret = adp8870_write(client, ADP8870_ISCLAW, pdata->led_fade_law);
255 	if (ret)
256 		return ret;
257 
258 	ret = adp8870_write(client, ADP8870_ISCT1,
259 			(pdata->led_on_time & 0x3) << 6);
260 	if (ret)
261 		return ret;
262 
263 	ret = adp8870_write(client, ADP8870_ISCF,
264 			FADE_VAL(pdata->led_fade_in, pdata->led_fade_out));
265 	if (ret)
266 		return ret;
267 
268 	for (i = 0; i < pdata->num_leds; ++i) {
269 		cur_led = &pdata->leds[i];
270 		led_dat = &led[i];
271 
272 		led_dat->id = cur_led->flags & ADP8870_FLAG_LED_MASK;
273 
274 		if (led_dat->id > 7 || led_dat->id < 1) {
275 			dev_err(&client->dev, "Invalid LED ID %d\n",
276 				led_dat->id);
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 			goto err;
284 		}
285 
286 		led_dat->cdev.name = cur_led->name;
287 		led_dat->cdev.default_trigger = cur_led->default_trigger;
288 		led_dat->cdev.brightness_set = adp8870_led_set;
289 		led_dat->cdev.brightness = LED_OFF;
290 		led_dat->flags = cur_led->flags >> FLAG_OFFT_SHIFT;
291 		led_dat->client = client;
292 		led_dat->new_brightness = LED_OFF;
293 		INIT_WORK(&led_dat->work, adp8870_led_work);
294 
295 		ret = led_classdev_register(&client->dev, &led_dat->cdev);
296 		if (ret) {
297 			dev_err(&client->dev, "failed to register LED %d\n",
298 				led_dat->id);
299 			goto err;
300 		}
301 
302 		ret = adp8870_led_setup(led_dat);
303 		if (ret) {
304 			dev_err(&client->dev, "failed to write\n");
305 			i++;
306 			goto err;
307 		}
308 	}
309 
310 	data->led = led;
311 
312 	return 0;
313 
314  err:
315 	for (i = i - 1; i >= 0; --i) {
316 		led_classdev_unregister(&led[i].cdev);
317 		cancel_work_sync(&led[i].work);
318 	}
319 
320 	return ret;
321 }
322 
323 static int __devexit adp8870_led_remove(struct i2c_client *client)
324 {
325 	struct adp8870_backlight_platform_data *pdata =
326 		client->dev.platform_data;
327 	struct adp8870_bl *data = i2c_get_clientdata(client);
328 	int i;
329 
330 	for (i = 0; i < pdata->num_leds; i++) {
331 		led_classdev_unregister(&data->led[i].cdev);
332 		cancel_work_sync(&data->led[i].work);
333 	}
334 
335 	return 0;
336 }
337 #else
338 static int __devinit adp8870_led_probe(struct i2c_client *client)
339 {
340 	return 0;
341 }
342 
343 static int __devexit adp8870_led_remove(struct i2c_client *client)
344 {
345 	return 0;
346 }
347 #endif
348 
349 static int adp8870_bl_set(struct backlight_device *bl, int brightness)
350 {
351 	struct adp8870_bl *data = bl_get_data(bl);
352 	struct i2c_client *client = data->client;
353 	int ret = 0;
354 
355 	if (data->pdata->en_ambl_sens) {
356 		if ((brightness > 0) && (brightness < ADP8870_MAX_BRIGHTNESS)) {
357 			/* Disable Ambient Light auto adjust */
358 			ret = adp8870_clr_bits(client, ADP8870_MDCR,
359 					CMP_AUTOEN);
360 			if (ret)
361 				return ret;
362 			ret = adp8870_write(client, ADP8870_BLMX1, brightness);
363 			if (ret)
364 				return ret;
365 		} else {
366 			/*
367 			 * MAX_BRIGHTNESS -> Enable Ambient Light auto adjust
368 			 * restore daylight l1 sysfs brightness
369 			 */
370 			ret = adp8870_write(client, ADP8870_BLMX1,
371 					 data->cached_daylight_max);
372 			if (ret)
373 				return ret;
374 
375 			ret = adp8870_set_bits(client, ADP8870_MDCR,
376 					 CMP_AUTOEN);
377 			if (ret)
378 				return ret;
379 		}
380 	} else {
381 		ret = adp8870_write(client, ADP8870_BLMX1, brightness);
382 		if (ret)
383 			return ret;
384 	}
385 
386 	if (data->current_brightness && brightness == 0)
387 		ret = adp8870_set_bits(client,
388 				ADP8870_MDCR, DIM_EN);
389 	else if (data->current_brightness == 0 && brightness)
390 		ret = adp8870_clr_bits(client,
391 				ADP8870_MDCR, DIM_EN);
392 
393 	if (!ret)
394 		data->current_brightness = brightness;
395 
396 	return ret;
397 }
398 
399 static int adp8870_bl_update_status(struct backlight_device *bl)
400 {
401 	int brightness = bl->props.brightness;
402 	if (bl->props.power != FB_BLANK_UNBLANK)
403 		brightness = 0;
404 
405 	if (bl->props.fb_blank != FB_BLANK_UNBLANK)
406 		brightness = 0;
407 
408 	return adp8870_bl_set(bl, brightness);
409 }
410 
411 static int adp8870_bl_get_brightness(struct backlight_device *bl)
412 {
413 	struct adp8870_bl *data = bl_get_data(bl);
414 
415 	return data->current_brightness;
416 }
417 
418 static const struct backlight_ops adp8870_bl_ops = {
419 	.update_status	= adp8870_bl_update_status,
420 	.get_brightness	= adp8870_bl_get_brightness,
421 };
422 
423 static int adp8870_bl_setup(struct backlight_device *bl)
424 {
425 	struct adp8870_bl *data = bl_get_data(bl);
426 	struct i2c_client *client = data->client;
427 	struct adp8870_backlight_platform_data *pdata = data->pdata;
428 	int ret = 0;
429 
430 	ret = adp8870_write(client, ADP8870_BLSEL, ~pdata->bl_led_assign);
431 	if (ret)
432 		return ret;
433 
434 	ret = adp8870_write(client, ADP8870_PWMLED, pdata->pwm_assign);
435 	if (ret)
436 		return ret;
437 
438 	ret = adp8870_write(client, ADP8870_BLMX1, pdata->l1_daylight_max);
439 	if (ret)
440 		return ret;
441 
442 	ret = adp8870_write(client, ADP8870_BLDM1, pdata->l1_daylight_dim);
443 	if (ret)
444 		return ret;
445 
446 	if (pdata->en_ambl_sens) {
447 		data->cached_daylight_max = pdata->l1_daylight_max;
448 		ret = adp8870_write(client, ADP8870_BLMX2,
449 						pdata->l2_bright_max);
450 		if (ret)
451 			return ret;
452 		ret = adp8870_write(client, ADP8870_BLDM2,
453 						pdata->l2_bright_dim);
454 		if (ret)
455 			return ret;
456 
457 		ret = adp8870_write(client, ADP8870_BLMX3,
458 						pdata->l3_office_max);
459 		if (ret)
460 			return ret;
461 		ret = adp8870_write(client, ADP8870_BLDM3,
462 						pdata->l3_office_dim);
463 		if (ret)
464 			return ret;
465 
466 		ret = adp8870_write(client, ADP8870_BLMX4,
467 						pdata->l4_indoor_max);
468 		if (ret)
469 			return ret;
470 
471 		ret = adp8870_write(client, ADP8870_BLDM4,
472 						pdata->l4_indor_dim);
473 		if (ret)
474 			return ret;
475 
476 		ret = adp8870_write(client, ADP8870_BLMX5,
477 						pdata->l5_dark_max);
478 		if (ret)
479 			return ret;
480 
481 		ret = adp8870_write(client, ADP8870_BLDM5,
482 						pdata->l5_dark_dim);
483 		if (ret)
484 			return ret;
485 
486 		ret = adp8870_write(client, ADP8870_L2TRP, pdata->l2_trip);
487 		if (ret)
488 			return ret;
489 
490 		ret = adp8870_write(client, ADP8870_L2HYS, pdata->l2_hyst);
491 		if (ret)
492 			return ret;
493 
494 		ret = adp8870_write(client, ADP8870_L3TRP, pdata->l3_trip);
495 		if (ret)
496 			return ret;
497 
498 		ret = adp8870_write(client, ADP8870_L3HYS, pdata->l3_hyst);
499 		if (ret)
500 			return ret;
501 
502 		ret = adp8870_write(client, ADP8870_L4TRP, pdata->l4_trip);
503 		if (ret)
504 			return ret;
505 
506 		ret = adp8870_write(client, ADP8870_L4HYS, pdata->l4_hyst);
507 		if (ret)
508 			return ret;
509 
510 		ret = adp8870_write(client, ADP8870_L5TRP, pdata->l5_trip);
511 		if (ret)
512 			return ret;
513 
514 		ret = adp8870_write(client, ADP8870_L5HYS, pdata->l5_hyst);
515 		if (ret)
516 			return ret;
517 
518 		ret = adp8870_write(client, ADP8870_ALS1_EN, L5_EN | L4_EN |
519 						L3_EN | L2_EN);
520 		if (ret)
521 			return ret;
522 
523 		ret = adp8870_write(client, ADP8870_CMP_CTL,
524 			ALS_CMPR_CFG_VAL(pdata->abml_filt));
525 		if (ret)
526 			return ret;
527 	}
528 
529 	ret = adp8870_write(client, ADP8870_CFGR,
530 			BL_CFGR_VAL(pdata->bl_fade_law, 0));
531 	if (ret)
532 		return ret;
533 
534 	ret = adp8870_write(client, ADP8870_BLFR, FADE_VAL(pdata->bl_fade_in,
535 			pdata->bl_fade_out));
536 	if (ret)
537 		return ret;
538 	/*
539 	 * ADP8870 Rev0 requires GDWN_DIS bit set
540 	 */
541 
542 	ret = adp8870_set_bits(client, ADP8870_MDCR, BLEN | DIM_EN | NSTBY |
543 			(data->revid == 0 ? GDWN_DIS : 0));
544 
545 	return ret;
546 }
547 
548 static ssize_t adp8870_show(struct device *dev, char *buf, int reg)
549 {
550 	struct adp8870_bl *data = dev_get_drvdata(dev);
551 	int error;
552 	uint8_t reg_val;
553 
554 	mutex_lock(&data->lock);
555 	error = adp8870_read(data->client, reg, &reg_val);
556 	mutex_unlock(&data->lock);
557 
558 	if (error < 0)
559 		return error;
560 
561 	return sprintf(buf, "%u\n", reg_val);
562 }
563 
564 static ssize_t adp8870_store(struct device *dev, const char *buf,
565 			 size_t count, int reg)
566 {
567 	struct adp8870_bl *data = dev_get_drvdata(dev);
568 	unsigned long val;
569 	int ret;
570 
571 	ret = kstrtoul(buf, 10, &val);
572 	if (ret)
573 		return ret;
574 
575 	mutex_lock(&data->lock);
576 	adp8870_write(data->client, reg, val);
577 	mutex_unlock(&data->lock);
578 
579 	return count;
580 }
581 
582 static ssize_t adp8870_bl_l5_dark_max_show(struct device *dev,
583 		struct device_attribute *attr, char *buf)
584 {
585 	return adp8870_show(dev, buf, ADP8870_BLMX5);
586 }
587 
588 static ssize_t adp8870_bl_l5_dark_max_store(struct device *dev,
589 		struct device_attribute *attr, const char *buf, size_t count)
590 {
591 	return adp8870_store(dev, buf, count, ADP8870_BLMX5);
592 }
593 static DEVICE_ATTR(l5_dark_max, 0664, adp8870_bl_l5_dark_max_show,
594 			adp8870_bl_l5_dark_max_store);
595 
596 
597 static ssize_t adp8870_bl_l4_indoor_max_show(struct device *dev,
598 		struct device_attribute *attr, char *buf)
599 {
600 	return adp8870_show(dev, buf, ADP8870_BLMX4);
601 }
602 
603 static ssize_t adp8870_bl_l4_indoor_max_store(struct device *dev,
604 		struct device_attribute *attr, const char *buf, size_t count)
605 {
606 	return adp8870_store(dev, buf, count, ADP8870_BLMX4);
607 }
608 static DEVICE_ATTR(l4_indoor_max, 0664, adp8870_bl_l4_indoor_max_show,
609 			adp8870_bl_l4_indoor_max_store);
610 
611 
612 static ssize_t adp8870_bl_l3_office_max_show(struct device *dev,
613 				     struct device_attribute *attr, char *buf)
614 {
615 	return adp8870_show(dev, buf, ADP8870_BLMX3);
616 }
617 
618 static ssize_t adp8870_bl_l3_office_max_store(struct device *dev,
619 		struct device_attribute *attr, const char *buf, size_t count)
620 {
621 	return adp8870_store(dev, buf, count, ADP8870_BLMX3);
622 }
623 
624 static DEVICE_ATTR(l3_office_max, 0664, adp8870_bl_l3_office_max_show,
625 			adp8870_bl_l3_office_max_store);
626 
627 static ssize_t adp8870_bl_l2_bright_max_show(struct device *dev,
628 		struct device_attribute *attr, char *buf)
629 {
630 	return adp8870_show(dev, buf, ADP8870_BLMX2);
631 }
632 
633 static ssize_t adp8870_bl_l2_bright_max_store(struct device *dev,
634 		struct device_attribute *attr, const char *buf, size_t count)
635 {
636 	return adp8870_store(dev, buf, count, ADP8870_BLMX2);
637 }
638 static DEVICE_ATTR(l2_bright_max, 0664, adp8870_bl_l2_bright_max_show,
639 			adp8870_bl_l2_bright_max_store);
640 
641 static ssize_t adp8870_bl_l1_daylight_max_show(struct device *dev,
642 			struct device_attribute *attr, char *buf)
643 {
644 	return adp8870_show(dev, buf, ADP8870_BLMX1);
645 }
646 
647 static ssize_t adp8870_bl_l1_daylight_max_store(struct device *dev,
648 		struct device_attribute *attr, const char *buf, size_t count)
649 {
650 	struct adp8870_bl *data = dev_get_drvdata(dev);
651 	int ret = kstrtoul(buf, 10, &data->cached_daylight_max);
652 	if (ret)
653 		return ret;
654 
655 	return adp8870_store(dev, buf, count, ADP8870_BLMX1);
656 }
657 static DEVICE_ATTR(l1_daylight_max, 0664, adp8870_bl_l1_daylight_max_show,
658 			adp8870_bl_l1_daylight_max_store);
659 
660 static ssize_t adp8870_bl_l5_dark_dim_show(struct device *dev,
661 			struct device_attribute *attr, char *buf)
662 {
663 	return adp8870_show(dev, buf, ADP8870_BLDM5);
664 }
665 
666 static ssize_t adp8870_bl_l5_dark_dim_store(struct device *dev,
667 				     struct device_attribute *attr,
668 				     const char *buf, size_t count)
669 {
670 	return adp8870_store(dev, buf, count, ADP8870_BLDM5);
671 }
672 static DEVICE_ATTR(l5_dark_dim, 0664, adp8870_bl_l5_dark_dim_show,
673 			adp8870_bl_l5_dark_dim_store);
674 
675 static ssize_t adp8870_bl_l4_indoor_dim_show(struct device *dev,
676 			struct device_attribute *attr, char *buf)
677 {
678 	return adp8870_show(dev, buf, ADP8870_BLDM4);
679 }
680 
681 static ssize_t adp8870_bl_l4_indoor_dim_store(struct device *dev,
682 				     struct device_attribute *attr,
683 				     const char *buf, size_t count)
684 {
685 	return adp8870_store(dev, buf, count, ADP8870_BLDM4);
686 }
687 static DEVICE_ATTR(l4_indoor_dim, 0664, adp8870_bl_l4_indoor_dim_show,
688 			adp8870_bl_l4_indoor_dim_store);
689 
690 
691 static ssize_t adp8870_bl_l3_office_dim_show(struct device *dev,
692 			struct device_attribute *attr, char *buf)
693 {
694 	return adp8870_show(dev, buf, ADP8870_BLDM3);
695 }
696 
697 static ssize_t adp8870_bl_l3_office_dim_store(struct device *dev,
698 				     struct device_attribute *attr,
699 				     const char *buf, size_t count)
700 {
701 	return adp8870_store(dev, buf, count, ADP8870_BLDM3);
702 }
703 static DEVICE_ATTR(l3_office_dim, 0664, adp8870_bl_l3_office_dim_show,
704 			adp8870_bl_l3_office_dim_store);
705 
706 static ssize_t adp8870_bl_l2_bright_dim_show(struct device *dev,
707 			struct device_attribute *attr, char *buf)
708 {
709 	return adp8870_show(dev, buf, ADP8870_BLDM2);
710 }
711 
712 static ssize_t adp8870_bl_l2_bright_dim_store(struct device *dev,
713 				     struct device_attribute *attr,
714 				     const char *buf, size_t count)
715 {
716 	return adp8870_store(dev, buf, count, ADP8870_BLDM2);
717 }
718 static DEVICE_ATTR(l2_bright_dim, 0664, adp8870_bl_l2_bright_dim_show,
719 			adp8870_bl_l2_bright_dim_store);
720 
721 static ssize_t adp8870_bl_l1_daylight_dim_show(struct device *dev,
722 				     struct device_attribute *attr, char *buf)
723 {
724 	return adp8870_show(dev, buf, ADP8870_BLDM1);
725 }
726 
727 static ssize_t adp8870_bl_l1_daylight_dim_store(struct device *dev,
728 				     struct device_attribute *attr,
729 				     const char *buf, size_t count)
730 {
731 	return adp8870_store(dev, buf, count, ADP8870_BLDM1);
732 }
733 static DEVICE_ATTR(l1_daylight_dim, 0664, adp8870_bl_l1_daylight_dim_show,
734 			adp8870_bl_l1_daylight_dim_store);
735 
736 #ifdef ADP8870_EXT_FEATURES
737 static ssize_t adp8870_bl_ambient_light_level_show(struct device *dev,
738 				     struct device_attribute *attr, char *buf)
739 {
740 	struct adp8870_bl *data = dev_get_drvdata(dev);
741 	int error;
742 	uint8_t reg_val;
743 	uint16_t ret_val;
744 
745 	mutex_lock(&data->lock);
746 	error = adp8870_read(data->client, ADP8870_PH1LEVL, &reg_val);
747 	if (error < 0) {
748 		mutex_unlock(&data->lock);
749 		return error;
750 	}
751 	ret_val = reg_val;
752 	error = adp8870_read(data->client, ADP8870_PH1LEVH, &reg_val);
753 	mutex_unlock(&data->lock);
754 
755 	if (error < 0)
756 		return error;
757 
758 	/* Return 13-bit conversion value for the first light sensor */
759 	ret_val += (reg_val & 0x1F) << 8;
760 
761 	return sprintf(buf, "%u\n", ret_val);
762 }
763 static DEVICE_ATTR(ambient_light_level, 0444,
764 		adp8870_bl_ambient_light_level_show, NULL);
765 
766 static ssize_t adp8870_bl_ambient_light_zone_show(struct device *dev,
767 				     struct device_attribute *attr, char *buf)
768 {
769 	struct adp8870_bl *data = dev_get_drvdata(dev);
770 	int error;
771 	uint8_t reg_val;
772 
773 	mutex_lock(&data->lock);
774 	error = adp8870_read(data->client, ADP8870_CFGR, &reg_val);
775 	mutex_unlock(&data->lock);
776 
777 	if (error < 0)
778 		return error;
779 
780 	return sprintf(buf, "%u\n",
781 		((reg_val >> CFGR_BLV_SHIFT) & CFGR_BLV_MASK) + 1);
782 }
783 
784 static ssize_t adp8870_bl_ambient_light_zone_store(struct device *dev,
785 				     struct device_attribute *attr,
786 				     const char *buf, size_t count)
787 {
788 	struct adp8870_bl *data = dev_get_drvdata(dev);
789 	unsigned long val;
790 	uint8_t reg_val;
791 	int ret;
792 
793 	ret = kstrtoul(buf, 10, &val);
794 	if (ret)
795 		return ret;
796 
797 	if (val == 0) {
798 		/* Enable automatic ambient light sensing */
799 		adp8870_set_bits(data->client, ADP8870_MDCR, CMP_AUTOEN);
800 	} else if ((val > 0) && (val < 6)) {
801 		/* Disable automatic ambient light sensing */
802 		adp8870_clr_bits(data->client, ADP8870_MDCR, CMP_AUTOEN);
803 
804 		/* Set user supplied ambient light zone */
805 		mutex_lock(&data->lock);
806 		adp8870_read(data->client, ADP8870_CFGR, &reg_val);
807 		reg_val &= ~(CFGR_BLV_MASK << CFGR_BLV_SHIFT);
808 		reg_val |= (val - 1) << CFGR_BLV_SHIFT;
809 		adp8870_write(data->client, ADP8870_CFGR, reg_val);
810 		mutex_unlock(&data->lock);
811 	}
812 
813 	return count;
814 }
815 static DEVICE_ATTR(ambient_light_zone, 0664,
816 		adp8870_bl_ambient_light_zone_show,
817 		adp8870_bl_ambient_light_zone_store);
818 #endif
819 
820 static struct attribute *adp8870_bl_attributes[] = {
821 	&dev_attr_l5_dark_max.attr,
822 	&dev_attr_l5_dark_dim.attr,
823 	&dev_attr_l4_indoor_max.attr,
824 	&dev_attr_l4_indoor_dim.attr,
825 	&dev_attr_l3_office_max.attr,
826 	&dev_attr_l3_office_dim.attr,
827 	&dev_attr_l2_bright_max.attr,
828 	&dev_attr_l2_bright_dim.attr,
829 	&dev_attr_l1_daylight_max.attr,
830 	&dev_attr_l1_daylight_dim.attr,
831 #ifdef ADP8870_EXT_FEATURES
832 	&dev_attr_ambient_light_level.attr,
833 	&dev_attr_ambient_light_zone.attr,
834 #endif
835 	NULL
836 };
837 
838 static const struct attribute_group adp8870_bl_attr_group = {
839 	.attrs = adp8870_bl_attributes,
840 };
841 
842 static int __devinit adp8870_probe(struct i2c_client *client,
843 					const struct i2c_device_id *id)
844 {
845 	struct backlight_properties props;
846 	struct backlight_device *bl;
847 	struct adp8870_bl *data;
848 	struct adp8870_backlight_platform_data *pdata =
849 		client->dev.platform_data;
850 	uint8_t reg_val;
851 	int ret;
852 
853 	if (!i2c_check_functionality(client->adapter,
854 					I2C_FUNC_SMBUS_BYTE_DATA)) {
855 		dev_err(&client->dev, "SMBUS Byte Data not Supported\n");
856 		return -EIO;
857 	}
858 
859 	if (!pdata) {
860 		dev_err(&client->dev, "no platform data?\n");
861 		return -EINVAL;
862 	}
863 
864 	ret = adp8870_read(client, ADP8870_MFDVID, &reg_val);
865 	if (ret < 0)
866 		return -EIO;
867 
868 	if (ADP8870_MANID(reg_val) != ADP8870_MANUFID) {
869 		dev_err(&client->dev, "failed to probe\n");
870 		return -ENODEV;
871 	}
872 
873 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
874 	if (data == NULL)
875 		return -ENOMEM;
876 
877 	data->revid = ADP8870_DEVID(reg_val);
878 	data->client = client;
879 	data->pdata = pdata;
880 	data->id = id->driver_data;
881 	data->current_brightness = 0;
882 	i2c_set_clientdata(client, data);
883 
884 	mutex_init(&data->lock);
885 
886 	memset(&props, 0, sizeof(props));
887 	props.type = BACKLIGHT_RAW;
888 	props.max_brightness = props.brightness = ADP8870_MAX_BRIGHTNESS;
889 	bl = backlight_device_register(dev_driver_string(&client->dev),
890 			&client->dev, data, &adp8870_bl_ops, &props);
891 	if (IS_ERR(bl)) {
892 		dev_err(&client->dev, "failed to register backlight\n");
893 		return PTR_ERR(bl);
894 	}
895 
896 	data->bl = bl;
897 
898 	if (pdata->en_ambl_sens)
899 		ret = sysfs_create_group(&bl->dev.kobj,
900 			&adp8870_bl_attr_group);
901 
902 	if (ret) {
903 		dev_err(&client->dev, "failed to register sysfs\n");
904 		goto out1;
905 	}
906 
907 	ret = adp8870_bl_setup(bl);
908 	if (ret) {
909 		ret = -EIO;
910 		goto out;
911 	}
912 
913 	backlight_update_status(bl);
914 
915 	dev_info(&client->dev, "Rev.%d Backlight\n", data->revid);
916 
917 	if (pdata->num_leds)
918 		adp8870_led_probe(client);
919 
920 	return 0;
921 
922 out:
923 	if (data->pdata->en_ambl_sens)
924 		sysfs_remove_group(&data->bl->dev.kobj,
925 			&adp8870_bl_attr_group);
926 out1:
927 	backlight_device_unregister(bl);
928 
929 	return ret;
930 }
931 
932 static int __devexit adp8870_remove(struct i2c_client *client)
933 {
934 	struct adp8870_bl *data = i2c_get_clientdata(client);
935 
936 	adp8870_clr_bits(client, ADP8870_MDCR, NSTBY);
937 
938 	if (data->led)
939 		adp8870_led_remove(client);
940 
941 	if (data->pdata->en_ambl_sens)
942 		sysfs_remove_group(&data->bl->dev.kobj,
943 			&adp8870_bl_attr_group);
944 
945 	backlight_device_unregister(data->bl);
946 
947 	return 0;
948 }
949 
950 #ifdef CONFIG_PM
951 static int adp8870_i2c_suspend(struct i2c_client *client, pm_message_t message)
952 {
953 	adp8870_clr_bits(client, ADP8870_MDCR, NSTBY);
954 
955 	return 0;
956 }
957 
958 static int adp8870_i2c_resume(struct i2c_client *client)
959 {
960 	adp8870_set_bits(client, ADP8870_MDCR, NSTBY);
961 
962 	return 0;
963 }
964 #else
965 #define adp8870_i2c_suspend NULL
966 #define adp8870_i2c_resume NULL
967 #endif
968 
969 static const struct i2c_device_id adp8870_id[] = {
970 	{ "adp8870", 0 },
971 	{ }
972 };
973 MODULE_DEVICE_TABLE(i2c, adp8870_id);
974 
975 static struct i2c_driver adp8870_driver = {
976 	.driver = {
977 		.name = KBUILD_MODNAME,
978 	},
979 	.probe    = adp8870_probe,
980 	.remove   = __devexit_p(adp8870_remove),
981 	.suspend = adp8870_i2c_suspend,
982 	.resume  = adp8870_i2c_resume,
983 	.id_table = adp8870_id,
984 };
985 
986 module_i2c_driver(adp8870_driver);
987 
988 MODULE_LICENSE("GPL v2");
989 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
990 MODULE_DESCRIPTION("ADP8870 Backlight driver");
991 MODULE_ALIAS("i2c:adp8870-backlight");
992