xref: /openbmc/linux/drivers/video/backlight/adp8870_bl.c (revision a59ec1e7ff98cc4365d5b1bff4e7102e86b5716b)
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/version.h>
11 #include <linux/init.h>
12 #include <linux/errno.h>
13 #include <linux/pm.h>
14 #include <linux/platform_device.h>
15 #include <linux/i2c.h>
16 #include <linux/fb.h>
17 #include <linux/backlight.h>
18 #include <linux/leds.h>
19 #include <linux/workqueue.h>
20 #include <linux/slab.h>
21 
22 #include <linux/i2c/adp8870.h>
23 #define ADP8870_EXT_FEATURES
24 #define ADP8870_USE_LEDS
25 
26 
27 #define ADP8870_MFDVID	0x00  /* Manufacturer and device ID */
28 #define ADP8870_MDCR	0x01  /* Device mode and status */
29 #define ADP8870_INT_STAT 0x02  /* Interrupts status */
30 #define ADP8870_INT_EN	0x03  /* Interrupts enable */
31 #define ADP8870_CFGR	0x04  /* Configuration register */
32 #define ADP8870_BLSEL	0x05  /* Sink enable backlight or independent */
33 #define ADP8870_PWMLED	0x06  /* PWM Enable Selection Register */
34 #define ADP8870_BLOFF	0x07  /* Backlight off timeout */
35 #define ADP8870_BLDIM	0x08  /* Backlight dim timeout */
36 #define ADP8870_BLFR	0x09  /* Backlight fade in and out rates */
37 #define ADP8870_BLMX1	0x0A  /* Backlight (Brightness Level 1-daylight) maximum current */
38 #define ADP8870_BLDM1	0x0B  /* Backlight (Brightness Level 1-daylight) dim current */
39 #define ADP8870_BLMX2	0x0C  /* Backlight (Brightness Level 2-bright) maximum current */
40 #define ADP8870_BLDM2	0x0D  /* Backlight (Brightness Level 2-bright) dim current */
41 #define ADP8870_BLMX3	0x0E  /* Backlight (Brightness Level 3-office) maximum current */
42 #define ADP8870_BLDM3	0x0F  /* Backlight (Brightness Level 3-office) dim current */
43 #define ADP8870_BLMX4	0x10  /* Backlight (Brightness Level 4-indoor) maximum current */
44 #define ADP8870_BLDM4	0x11  /* Backlight (Brightness Level 4-indoor) dim current */
45 #define ADP8870_BLMX5	0x12  /* Backlight (Brightness Level 5-dark) maximum current */
46 #define ADP8870_BLDM5	0x13  /* Backlight (Brightness Level 5-dark) dim current */
47 #define ADP8870_ISCLAW	0x1A  /* Independent sink current fade law register */
48 #define ADP8870_ISCC	0x1B  /* Independent sink current control register */
49 #define ADP8870_ISCT1	0x1C  /* Independent Sink Current Timer Register LED[7:5] */
50 #define ADP8870_ISCT2	0x1D  /* Independent Sink Current Timer Register LED[4:1] */
51 #define ADP8870_ISCF	0x1E  /* Independent sink current fade register */
52 #define ADP8870_ISC1	0x1F  /* Independent Sink Current LED1 */
53 #define ADP8870_ISC2	0x20  /* Independent Sink Current LED2 */
54 #define ADP8870_ISC3	0x21  /* Independent Sink Current LED3 */
55 #define ADP8870_ISC4	0x22  /* Independent Sink Current LED4 */
56 #define ADP8870_ISC5	0x23  /* Independent Sink Current LED5 */
57 #define ADP8870_ISC6	0x24  /* Independent Sink Current LED6 */
58 #define ADP8870_ISC7	0x25  /* Independent Sink Current LED7 (Brightness Level 1-daylight) */
59 #define ADP8870_ISC7_L2	0x26  /* Independent Sink Current LED7 (Brightness Level 2-bright) */
60 #define ADP8870_ISC7_L3	0x27  /* Independent Sink Current LED7 (Brightness Level 3-office) */
61 #define ADP8870_ISC7_L4	0x28  /* Independent Sink Current LED7 (Brightness Level 4-indoor) */
62 #define ADP8870_ISC7_L5	0x29  /* Independent Sink Current LED7 (Brightness Level 5-dark) */
63 #define ADP8870_CMP_CTL	0x2D  /* ALS Comparator Control Register */
64 #define ADP8870_ALS1_EN	0x2E  /* Main ALS comparator level enable */
65 #define ADP8870_ALS2_EN	0x2F  /* Second ALS comparator level enable */
66 #define ADP8870_ALS1_STAT 0x30  /* Main ALS Comparator Status Register */
67 #define ADP8870_ALS2_STAT 0x31  /* Second ALS Comparator Status Register */
68 #define ADP8870_L2TRP	0x32  /* L2 comparator reference */
69 #define ADP8870_L2HYS	0x33  /* L2 hysteresis */
70 #define ADP8870_L3TRP	0x34  /* L3 comparator reference */
71 #define ADP8870_L3HYS	0x35  /* L3 hysteresis */
72 #define ADP8870_L4TRP	0x36  /* L4 comparator reference */
73 #define ADP8870_L4HYS	0x37  /* L4 hysteresis */
74 #define ADP8870_L5TRP	0x38  /* L5 comparator reference */
75 #define ADP8870_L5HYS	0x39  /* L5 hysteresis */
76 #define ADP8870_PH1LEVL	0x40  /* First phototransistor ambient light level-low byte register */
77 #define ADP8870_PH1LEVH	0x41  /* First phototransistor ambient light level-high byte register */
78 #define ADP8870_PH2LEVL	0x42  /* Second phototransistor ambient light level-low byte register */
79 #define ADP8870_PH2LEVH	0x43  /* Second phototransistor ambient light level-high byte register */
80 
81 #define ADP8870_MANUFID		0x3  /* Analog Devices AD8870 Manufacturer and device ID */
82 #define ADP8870_DEVID(x)	((x) & 0xF)
83 #define ADP8870_MANID(x)	((x) >> 4)
84 
85 /* MDCR Device mode and status */
86 #define D7ALSEN			(1 << 7)
87 #define INT_CFG			(1 << 6)
88 #define NSTBY			(1 << 5)
89 #define DIM_EN			(1 << 4)
90 #define GDWN_DIS		(1 << 3)
91 #define SIS_EN			(1 << 2)
92 #define CMP_AUTOEN		(1 << 1)
93 #define BLEN			(1 << 0)
94 
95 /* ADP8870_ALS1_EN Main ALS comparator level enable */
96 #define L5_EN			(1 << 3)
97 #define L4_EN			(1 << 2)
98 #define L3_EN			(1 << 1)
99 #define L2_EN			(1 << 0)
100 
101 #define CFGR_BLV_SHIFT		3
102 #define CFGR_BLV_MASK		0x7
103 #define ADP8870_FLAG_LED_MASK	0xFF
104 
105 #define FADE_VAL(in, out)	((0xF & (in)) | ((0xF & (out)) << 4))
106 #define BL_CFGR_VAL(law, blv)	((((blv) & CFGR_BLV_MASK) << CFGR_BLV_SHIFT) | ((0x3 & (law)) << 1))
107 #define ALS_CMPR_CFG_VAL(filt)	((0x7 & (filt)) << 1)
108 
109 struct adp8870_bl {
110 	struct i2c_client *client;
111 	struct backlight_device *bl;
112 	struct adp8870_led *led;
113 	struct adp8870_backlight_platform_data *pdata;
114 	struct mutex lock;
115 	unsigned long cached_daylight_max;
116 	int id;
117 	int revid;
118 	int current_brightness;
119 };
120 
121 struct adp8870_led {
122 	struct led_classdev	cdev;
123 	struct work_struct	work;
124 	struct i2c_client	*client;
125 	enum led_brightness	new_brightness;
126 	int			id;
127 	int			flags;
128 };
129 
130 static int adp8870_read(struct i2c_client *client, int reg, uint8_t *val)
131 {
132 	int ret;
133 
134 	ret = i2c_smbus_read_byte_data(client, reg);
135 	if (ret < 0) {
136 		dev_err(&client->dev, "failed reading at 0x%02x\n", reg);
137 		return ret;
138 	}
139 
140 	*val = ret;
141 	return 0;
142 }
143 
144 
145 static int adp8870_write(struct i2c_client *client, u8 reg, u8 val)
146 {
147 	int ret = i2c_smbus_write_byte_data(client, reg, val);
148 	if (ret)
149 		dev_err(&client->dev, "failed to write\n");
150 
151 	return ret;
152 }
153 
154 static int adp8870_set_bits(struct i2c_client *client, int reg, uint8_t bit_mask)
155 {
156 	struct adp8870_bl *data = i2c_get_clientdata(client);
157 	uint8_t reg_val;
158 	int ret;
159 
160 	mutex_lock(&data->lock);
161 
162 	ret = adp8870_read(client, reg, &reg_val);
163 
164 	if (!ret && ((reg_val & bit_mask) == 0)) {
165 		reg_val |= bit_mask;
166 		ret = adp8870_write(client, reg, reg_val);
167 	}
168 
169 	mutex_unlock(&data->lock);
170 	return ret;
171 }
172 
173 static int adp8870_clr_bits(struct i2c_client *client, int reg, uint8_t bit_mask)
174 {
175 	struct adp8870_bl *data = i2c_get_clientdata(client);
176 	uint8_t reg_val;
177 	int ret;
178 
179 	mutex_lock(&data->lock);
180 
181 	ret = adp8870_read(client, reg, &reg_val);
182 
183 	if (!ret && (reg_val & bit_mask)) {
184 		reg_val &= ~bit_mask;
185 		ret = adp8870_write(client, reg, reg_val);
186 	}
187 
188 	mutex_unlock(&data->lock);
189 	return ret;
190 }
191 
192 /*
193  * Independent sink / LED
194  */
195 #if defined(ADP8870_USE_LEDS)
196 static void adp8870_led_work(struct work_struct *work)
197 {
198 	struct adp8870_led *led = container_of(work, struct adp8870_led, work);
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 __devinit adp8870_led_probe(struct i2c_client *client)
240 {
241 	struct adp8870_backlight_platform_data *pdata =
242 		client->dev.platform_data;
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 
249 	led = kcalloc(pdata->num_leds, sizeof(*led), GFP_KERNEL);
250 	if (led == NULL) {
251 		dev_err(&client->dev, "failed to alloc memory\n");
252 		return -ENOMEM;
253 	}
254 
255 	ret = adp8870_write(client, ADP8870_ISCLAW, pdata->led_fade_law);
256 	if (ret)
257 		goto err_free;
258 
259 	ret = adp8870_write(client, ADP8870_ISCT1,
260 			(pdata->led_on_time & 0x3) << 6);
261 	if (ret)
262 		goto err_free;
263 
264 	ret = adp8870_write(client, ADP8870_ISCF,
265 			FADE_VAL(pdata->led_fade_in, pdata->led_fade_out));
266 	if (ret)
267 		goto err_free;
268 
269 	for (i = 0; i < pdata->num_leds; ++i) {
270 		cur_led = &pdata->leds[i];
271 		led_dat = &led[i];
272 
273 		led_dat->id = cur_led->flags & ADP8870_FLAG_LED_MASK;
274 
275 		if (led_dat->id > 7 || led_dat->id < 1) {
276 			dev_err(&client->dev, "Invalid LED ID %d\n",
277 				led_dat->id);
278 			goto err;
279 		}
280 
281 		if (pdata->bl_led_assign & (1 << (led_dat->id - 1))) {
282 			dev_err(&client->dev, "LED %d used by Backlight\n",
283 				led_dat->id);
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  err_free:
322 	kfree(led);
323 
324 	return ret;
325 }
326 
327 static int __devexit adp8870_led_remove(struct i2c_client *client)
328 {
329 	struct adp8870_backlight_platform_data *pdata =
330 		client->dev.platform_data;
331 	struct adp8870_bl *data = i2c_get_clientdata(client);
332 	int i;
333 
334 	for (i = 0; i < pdata->num_leds; i++) {
335 		led_classdev_unregister(&data->led[i].cdev);
336 		cancel_work_sync(&data->led[i].work);
337 	}
338 
339 	kfree(data->led);
340 	return 0;
341 }
342 #else
343 static int __devinit adp8870_led_probe(struct i2c_client *client)
344 {
345 	return 0;
346 }
347 
348 static int __devexit adp8870_led_remove(struct i2c_client *client)
349 {
350 	return 0;
351 }
352 #endif
353 
354 static int adp8870_bl_set(struct backlight_device *bl, int brightness)
355 {
356 	struct adp8870_bl *data = bl_get_data(bl);
357 	struct i2c_client *client = data->client;
358 	int ret = 0;
359 
360 	if (data->pdata->en_ambl_sens) {
361 		if ((brightness > 0) && (brightness < ADP8870_MAX_BRIGHTNESS)) {
362 			/* Disable Ambient Light auto adjust */
363 			ret = adp8870_clr_bits(client, ADP8870_MDCR,
364 					CMP_AUTOEN);
365 			if (ret)
366 				return ret;
367 			ret = adp8870_write(client, ADP8870_BLMX1, brightness);
368 			if (ret)
369 				return ret;
370 		} else {
371 			/*
372 			 * MAX_BRIGHTNESS -> Enable Ambient Light auto adjust
373 			 * restore daylight l1 sysfs brightness
374 			 */
375 			ret = adp8870_write(client, ADP8870_BLMX1,
376 					 data->cached_daylight_max);
377 			if (ret)
378 				return ret;
379 
380 			ret = adp8870_set_bits(client, ADP8870_MDCR,
381 					 CMP_AUTOEN);
382 			if (ret)
383 				return ret;
384 		}
385 	} else {
386 		ret = adp8870_write(client, ADP8870_BLMX1, brightness);
387 		if (ret)
388 			return ret;
389 	}
390 
391 	if (data->current_brightness && brightness == 0)
392 		ret = adp8870_set_bits(client,
393 				ADP8870_MDCR, DIM_EN);
394 	else if (data->current_brightness == 0 && brightness)
395 		ret = adp8870_clr_bits(client,
396 				ADP8870_MDCR, DIM_EN);
397 
398 	if (!ret)
399 		data->current_brightness = brightness;
400 
401 	return ret;
402 }
403 
404 static int adp8870_bl_update_status(struct backlight_device *bl)
405 {
406 	int brightness = bl->props.brightness;
407 	if (bl->props.power != FB_BLANK_UNBLANK)
408 		brightness = 0;
409 
410 	if (bl->props.fb_blank != FB_BLANK_UNBLANK)
411 		brightness = 0;
412 
413 	return adp8870_bl_set(bl, brightness);
414 }
415 
416 static int adp8870_bl_get_brightness(struct backlight_device *bl)
417 {
418 	struct adp8870_bl *data = bl_get_data(bl);
419 
420 	return data->current_brightness;
421 }
422 
423 static const struct backlight_ops adp8870_bl_ops = {
424 	.update_status	= adp8870_bl_update_status,
425 	.get_brightness	= adp8870_bl_get_brightness,
426 };
427 
428 static int adp8870_bl_setup(struct backlight_device *bl)
429 {
430 	struct adp8870_bl *data = bl_get_data(bl);
431 	struct i2c_client *client = data->client;
432 	struct adp8870_backlight_platform_data *pdata = data->pdata;
433 	int ret = 0;
434 
435 	ret = adp8870_write(client, ADP8870_BLSEL, ~pdata->bl_led_assign);
436 	if (ret)
437 		return ret;
438 
439 	ret = adp8870_write(client, ADP8870_PWMLED, pdata->pwm_assign);
440 	if (ret)
441 		return ret;
442 
443 	ret = adp8870_write(client, ADP8870_BLMX1, pdata->l1_daylight_max);
444 	if (ret)
445 		return ret;
446 
447 	ret = adp8870_write(client, ADP8870_BLDM1, pdata->l1_daylight_dim);
448 	if (ret)
449 		return ret;
450 
451 	if (pdata->en_ambl_sens) {
452 		data->cached_daylight_max = pdata->l1_daylight_max;
453 		ret = adp8870_write(client, ADP8870_BLMX2,
454 						pdata->l2_bright_max);
455 		if (ret)
456 			return ret;
457 		ret = adp8870_write(client, ADP8870_BLDM2,
458 						pdata->l2_bright_dim);
459 		if (ret)
460 			return ret;
461 
462 		ret = adp8870_write(client, ADP8870_BLMX3,
463 						pdata->l3_office_max);
464 		if (ret)
465 			return ret;
466 		ret = adp8870_write(client, ADP8870_BLDM3,
467 						pdata->l3_office_dim);
468 		if (ret)
469 			return ret;
470 
471 		ret = adp8870_write(client, ADP8870_BLMX4,
472 						pdata->l4_indoor_max);
473 		if (ret)
474 			return ret;
475 
476 		ret = adp8870_write(client, ADP8870_BLDM4,
477 						pdata->l4_indor_dim);
478 		if (ret)
479 			return ret;
480 
481 		ret = adp8870_write(client, ADP8870_BLMX5,
482 						pdata->l5_dark_max);
483 		if (ret)
484 			return ret;
485 
486 		ret = adp8870_write(client, ADP8870_BLDM5,
487 						pdata->l5_dark_dim);
488 		if (ret)
489 			return ret;
490 
491 		ret = adp8870_write(client, ADP8870_L2TRP, pdata->l2_trip);
492 		if (ret)
493 			return ret;
494 
495 		ret = adp8870_write(client, ADP8870_L2HYS, pdata->l2_hyst);
496 		if (ret)
497 			return ret;
498 
499 		ret = adp8870_write(client, ADP8870_L3TRP, pdata->l3_trip);
500 		if (ret)
501 			return ret;
502 
503 		ret = adp8870_write(client, ADP8870_L3HYS, pdata->l3_hyst);
504 		if (ret)
505 			return ret;
506 
507 		ret = adp8870_write(client, ADP8870_L4TRP, pdata->l4_trip);
508 		if (ret)
509 			return ret;
510 
511 		ret = adp8870_write(client, ADP8870_L4HYS, pdata->l4_hyst);
512 		if (ret)
513 			return ret;
514 
515 		ret = adp8870_write(client, ADP8870_L5TRP, pdata->l5_trip);
516 		if (ret)
517 			return ret;
518 
519 		ret = adp8870_write(client, ADP8870_L5HYS, pdata->l5_hyst);
520 		if (ret)
521 			return ret;
522 
523 		ret = adp8870_write(client, ADP8870_ALS1_EN, L5_EN | L4_EN |
524 						L3_EN | L2_EN);
525 		if (ret)
526 			return ret;
527 
528 		ret = adp8870_write(client, ADP8870_CMP_CTL,
529 			ALS_CMPR_CFG_VAL(pdata->abml_filt));
530 		if (ret)
531 			return ret;
532 	}
533 
534 	ret = adp8870_write(client, ADP8870_CFGR,
535 			BL_CFGR_VAL(pdata->bl_fade_law, 0));
536 	if (ret)
537 		return ret;
538 
539 	ret = adp8870_write(client, ADP8870_BLFR, FADE_VAL(pdata->bl_fade_in,
540 			pdata->bl_fade_out));
541 	if (ret)
542 		return ret;
543 	/*
544 	 * ADP8870 Rev0 requires GDWN_DIS bit set
545 	 */
546 
547 	ret = adp8870_set_bits(client, ADP8870_MDCR, BLEN | DIM_EN | NSTBY |
548 			(data->revid == 0 ? GDWN_DIS : 0));
549 
550 	return ret;
551 }
552 
553 static ssize_t adp8870_show(struct device *dev, char *buf, int reg)
554 {
555 	struct adp8870_bl *data = dev_get_drvdata(dev);
556 	int error;
557 	uint8_t reg_val;
558 
559 	mutex_lock(&data->lock);
560 	error = adp8870_read(data->client, reg, &reg_val);
561 	mutex_unlock(&data->lock);
562 
563 	if (error < 0)
564 		return error;
565 
566 	return sprintf(buf, "%u\n", reg_val);
567 }
568 
569 static ssize_t adp8870_store(struct device *dev, const char *buf,
570 			 size_t count, int reg)
571 {
572 	struct adp8870_bl *data = dev_get_drvdata(dev);
573 	unsigned long val;
574 	int ret;
575 
576 	ret = strict_strtoul(buf, 10, &val);
577 	if (ret)
578 		return ret;
579 
580 	mutex_lock(&data->lock);
581 	adp8870_write(data->client, reg, val);
582 	mutex_unlock(&data->lock);
583 
584 	return count;
585 }
586 
587 static ssize_t adp8870_bl_l5_dark_max_show(struct device *dev,
588 		struct device_attribute *attr, char *buf)
589 {
590 	return adp8870_show(dev, buf, ADP8870_BLMX5);
591 }
592 
593 static ssize_t adp8870_bl_l5_dark_max_store(struct device *dev,
594 		struct device_attribute *attr, const char *buf, size_t count)
595 {
596 	return adp8870_store(dev, buf, count, ADP8870_BLMX5);
597 }
598 static DEVICE_ATTR(l5_dark_max, 0664, adp8870_bl_l5_dark_max_show,
599 			adp8870_bl_l5_dark_max_store);
600 
601 
602 static ssize_t adp8870_bl_l4_indoor_max_show(struct device *dev,
603 		struct device_attribute *attr, char *buf)
604 {
605 	return adp8870_show(dev, buf, ADP8870_BLMX4);
606 }
607 
608 static ssize_t adp8870_bl_l4_indoor_max_store(struct device *dev,
609 		struct device_attribute *attr, const char *buf, size_t count)
610 {
611 	return adp8870_store(dev, buf, count, ADP8870_BLMX4);
612 }
613 static DEVICE_ATTR(l4_indoor_max, 0664, adp8870_bl_l4_indoor_max_show,
614 			adp8870_bl_l4_indoor_max_store);
615 
616 
617 static ssize_t adp8870_bl_l3_office_max_show(struct device *dev,
618 				     struct device_attribute *attr, char *buf)
619 {
620 	return adp8870_show(dev, buf, ADP8870_BLMX3);
621 }
622 
623 static ssize_t adp8870_bl_l3_office_max_store(struct device *dev,
624 		struct device_attribute *attr, const char *buf, size_t count)
625 {
626 	return adp8870_store(dev, buf, count, ADP8870_BLMX3);
627 }
628 
629 static DEVICE_ATTR(l3_office_max, 0664, adp8870_bl_l3_office_max_show,
630 			adp8870_bl_l3_office_max_store);
631 
632 static ssize_t adp8870_bl_l2_bright_max_show(struct device *dev,
633 		struct device_attribute *attr, char *buf)
634 {
635 	return adp8870_show(dev, buf, ADP8870_BLMX2);
636 }
637 
638 static ssize_t adp8870_bl_l2_bright_max_store(struct device *dev,
639 		struct device_attribute *attr, const char *buf, size_t count)
640 {
641 	return adp8870_store(dev, buf, count, ADP8870_BLMX2);
642 }
643 static DEVICE_ATTR(l2_bright_max, 0664, adp8870_bl_l2_bright_max_show,
644 			adp8870_bl_l2_bright_max_store);
645 
646 static ssize_t adp8870_bl_l1_daylight_max_show(struct device *dev,
647 			struct device_attribute *attr, char *buf)
648 {
649 	return adp8870_show(dev, buf, ADP8870_BLMX1);
650 }
651 
652 static ssize_t adp8870_bl_l1_daylight_max_store(struct device *dev,
653 		struct device_attribute *attr, const char *buf, size_t count)
654 {
655 	struct adp8870_bl *data = dev_get_drvdata(dev);
656 	int ret = strict_strtoul(buf, 10, &data->cached_daylight_max);
657 	if (ret)
658 		return ret;
659 
660 	return adp8870_store(dev, buf, count, ADP8870_BLMX1);
661 }
662 static DEVICE_ATTR(l1_daylight_max, 0664, adp8870_bl_l1_daylight_max_show,
663 			adp8870_bl_l1_daylight_max_store);
664 
665 static ssize_t adp8870_bl_l5_dark_dim_show(struct device *dev,
666 			struct device_attribute *attr, char *buf)
667 {
668 	return adp8870_show(dev, buf, ADP8870_BLDM5);
669 }
670 
671 static ssize_t adp8870_bl_l5_dark_dim_store(struct device *dev,
672 				     struct device_attribute *attr,
673 				     const char *buf, size_t count)
674 {
675 	return adp8870_store(dev, buf, count, ADP8870_BLDM5);
676 }
677 static DEVICE_ATTR(l5_dark_dim, 0664, adp8870_bl_l5_dark_dim_show,
678 			adp8870_bl_l5_dark_dim_store);
679 
680 static ssize_t adp8870_bl_l4_indoor_dim_show(struct device *dev,
681 			struct device_attribute *attr, char *buf)
682 {
683 	return adp8870_show(dev, buf, ADP8870_BLDM4);
684 }
685 
686 static ssize_t adp8870_bl_l4_indoor_dim_store(struct device *dev,
687 				     struct device_attribute *attr,
688 				     const char *buf, size_t count)
689 {
690 	return adp8870_store(dev, buf, count, ADP8870_BLDM4);
691 }
692 static DEVICE_ATTR(l4_indoor_dim, 0664, adp8870_bl_l4_indoor_dim_show,
693 			adp8870_bl_l4_indoor_dim_store);
694 
695 
696 static ssize_t adp8870_bl_l3_office_dim_show(struct device *dev,
697 			struct device_attribute *attr, char *buf)
698 {
699 	return adp8870_show(dev, buf, ADP8870_BLDM3);
700 }
701 
702 static ssize_t adp8870_bl_l3_office_dim_store(struct device *dev,
703 				     struct device_attribute *attr,
704 				     const char *buf, size_t count)
705 {
706 	return adp8870_store(dev, buf, count, ADP8870_BLDM3);
707 }
708 static DEVICE_ATTR(l3_office_dim, 0664, adp8870_bl_l3_office_dim_show,
709 			adp8870_bl_l3_office_dim_store);
710 
711 static ssize_t adp8870_bl_l2_bright_dim_show(struct device *dev,
712 			struct device_attribute *attr, char *buf)
713 {
714 	return adp8870_show(dev, buf, ADP8870_BLDM2);
715 }
716 
717 static ssize_t adp8870_bl_l2_bright_dim_store(struct device *dev,
718 				     struct device_attribute *attr,
719 				     const char *buf, size_t count)
720 {
721 	return adp8870_store(dev, buf, count, ADP8870_BLDM2);
722 }
723 static DEVICE_ATTR(l2_bright_dim, 0664, adp8870_bl_l2_bright_dim_show,
724 			adp8870_bl_l2_bright_dim_store);
725 
726 static ssize_t adp8870_bl_l1_daylight_dim_show(struct device *dev,
727 				     struct device_attribute *attr, char *buf)
728 {
729 	return adp8870_show(dev, buf, ADP8870_BLDM1);
730 }
731 
732 static ssize_t adp8870_bl_l1_daylight_dim_store(struct device *dev,
733 				     struct device_attribute *attr,
734 				     const char *buf, size_t count)
735 {
736 	return adp8870_store(dev, buf, count, ADP8870_BLDM1);
737 }
738 static DEVICE_ATTR(l1_daylight_dim, 0664, adp8870_bl_l1_daylight_dim_show,
739 			adp8870_bl_l1_daylight_dim_store);
740 
741 #ifdef ADP8870_EXT_FEATURES
742 static ssize_t adp8870_bl_ambient_light_level_show(struct device *dev,
743 				     struct device_attribute *attr, char *buf)
744 {
745 	struct adp8870_bl *data = dev_get_drvdata(dev);
746 	int error;
747 	uint8_t reg_val;
748 	uint16_t ret_val;
749 
750 	mutex_lock(&data->lock);
751 	error = adp8870_read(data->client, ADP8870_PH1LEVL, &reg_val);
752 	if (error < 0) {
753 		mutex_unlock(&data->lock);
754 		return error;
755 	}
756 	ret_val = reg_val;
757 	error = adp8870_read(data->client, ADP8870_PH1LEVH, &reg_val);
758 	mutex_unlock(&data->lock);
759 
760 	if (error < 0)
761 		return error;
762 
763 	/* Return 13-bit conversion value for the first light sensor */
764 	ret_val += (reg_val & 0x1F) << 8;
765 
766 	return sprintf(buf, "%u\n", ret_val);
767 }
768 static DEVICE_ATTR(ambient_light_level, 0444,
769 		adp8870_bl_ambient_light_level_show, NULL);
770 
771 static ssize_t adp8870_bl_ambient_light_zone_show(struct device *dev,
772 				     struct device_attribute *attr, char *buf)
773 {
774 	struct adp8870_bl *data = dev_get_drvdata(dev);
775 	int error;
776 	uint8_t reg_val;
777 
778 	mutex_lock(&data->lock);
779 	error = adp8870_read(data->client, ADP8870_CFGR, &reg_val);
780 	mutex_unlock(&data->lock);
781 
782 	if (error < 0)
783 		return error;
784 
785 	return sprintf(buf, "%u\n",
786 		((reg_val >> CFGR_BLV_SHIFT) & CFGR_BLV_MASK) + 1);
787 }
788 
789 static ssize_t adp8870_bl_ambient_light_zone_store(struct device *dev,
790 				     struct device_attribute *attr,
791 				     const char *buf, size_t count)
792 {
793 	struct adp8870_bl *data = dev_get_drvdata(dev);
794 	unsigned long val;
795 	uint8_t reg_val;
796 	int ret;
797 
798 	ret = strict_strtoul(buf, 10, &val);
799 	if (ret)
800 		return ret;
801 
802 	if (val == 0) {
803 		/* Enable automatic ambient light sensing */
804 		adp8870_set_bits(data->client, ADP8870_MDCR, CMP_AUTOEN);
805 	} else if ((val > 0) && (val < 6)) {
806 		/* Disable automatic ambient light sensing */
807 		adp8870_clr_bits(data->client, ADP8870_MDCR, CMP_AUTOEN);
808 
809 		/* Set user supplied ambient light zone */
810 		mutex_lock(&data->lock);
811 		adp8870_read(data->client, ADP8870_CFGR, &reg_val);
812 		reg_val &= ~(CFGR_BLV_MASK << CFGR_BLV_SHIFT);
813 		reg_val |= (val - 1) << CFGR_BLV_SHIFT;
814 		adp8870_write(data->client, ADP8870_CFGR, reg_val);
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 __devinit 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 		client->dev.platform_data;
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 = kzalloc(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.max_brightness = props.brightness = ADP8870_MAX_BRIGHTNESS;
893 	bl = backlight_device_register(dev_driver_string(&client->dev),
894 			&client->dev, data, &adp8870_bl_ops, &props);
895 	if (IS_ERR(bl)) {
896 		dev_err(&client->dev, "failed to register backlight\n");
897 		ret = PTR_ERR(bl);
898 		goto out2;
899 	}
900 
901 	data->bl = bl;
902 
903 	if (pdata->en_ambl_sens)
904 		ret = sysfs_create_group(&bl->dev.kobj,
905 			&adp8870_bl_attr_group);
906 
907 	if (ret) {
908 		dev_err(&client->dev, "failed to register sysfs\n");
909 		goto out1;
910 	}
911 
912 	ret = adp8870_bl_setup(bl);
913 	if (ret) {
914 		ret = -EIO;
915 		goto out;
916 	}
917 
918 	backlight_update_status(bl);
919 
920 	dev_info(&client->dev, "Rev.%d Backlight\n", data->revid);
921 
922 	if (pdata->num_leds)
923 		adp8870_led_probe(client);
924 
925 	return 0;
926 
927 out:
928 	if (data->pdata->en_ambl_sens)
929 		sysfs_remove_group(&data->bl->dev.kobj,
930 			&adp8870_bl_attr_group);
931 out1:
932 	backlight_device_unregister(bl);
933 out2:
934 	i2c_set_clientdata(client, NULL);
935 	kfree(data);
936 
937 	return ret;
938 }
939 
940 static int __devexit adp8870_remove(struct i2c_client *client)
941 {
942 	struct adp8870_bl *data = i2c_get_clientdata(client);
943 
944 	adp8870_clr_bits(client, ADP8870_MDCR, NSTBY);
945 
946 	if (data->led)
947 		adp8870_led_remove(client);
948 
949 	if (data->pdata->en_ambl_sens)
950 		sysfs_remove_group(&data->bl->dev.kobj,
951 			&adp8870_bl_attr_group);
952 
953 	backlight_device_unregister(data->bl);
954 	i2c_set_clientdata(client, NULL);
955 	kfree(data);
956 
957 	return 0;
958 }
959 
960 #ifdef CONFIG_PM
961 static int adp8870_i2c_suspend(struct i2c_client *client, pm_message_t message)
962 {
963 	adp8870_clr_bits(client, ADP8870_MDCR, NSTBY);
964 
965 	return 0;
966 }
967 
968 static int adp8870_i2c_resume(struct i2c_client *client)
969 {
970 	adp8870_set_bits(client, ADP8870_MDCR, NSTBY);
971 
972 	return 0;
973 }
974 #else
975 #define adp8870_i2c_suspend NULL
976 #define adp8870_i2c_resume NULL
977 #endif
978 
979 static const struct i2c_device_id adp8870_id[] = {
980 	{ "adp8870", 0 },
981 	{ }
982 };
983 MODULE_DEVICE_TABLE(i2c, adp8870_id);
984 
985 static struct i2c_driver adp8870_driver = {
986 	.driver = {
987 		.name = KBUILD_MODNAME,
988 	},
989 	.probe    = adp8870_probe,
990 	.remove   = __devexit_p(adp8870_remove),
991 	.suspend = adp8870_i2c_suspend,
992 	.resume  = adp8870_i2c_resume,
993 	.id_table = adp8870_id,
994 };
995 
996 static int __init adp8870_init(void)
997 {
998 	return i2c_add_driver(&adp8870_driver);
999 }
1000 module_init(adp8870_init);
1001 
1002 static void __exit adp8870_exit(void)
1003 {
1004 	i2c_del_driver(&adp8870_driver);
1005 }
1006 module_exit(adp8870_exit);
1007 
1008 MODULE_LICENSE("GPL v2");
1009 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
1010 MODULE_DESCRIPTION("ADP8870 Backlight driver");
1011 MODULE_ALIAS("platform:adp8870-backlight");
1012