1 /*
2  * Backlight driver for Analog Devices ADP5520/ADP5501 MFD PMICs
3  *
4  * Copyright 2009 Analog Devices Inc.
5  *
6  * Licensed under the GPL-2 or later.
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/platform_device.h>
12 #include <linux/fb.h>
13 #include <linux/backlight.h>
14 #include <linux/mfd/adp5520.h>
15 
16 struct adp5520_bl {
17 	struct device *master;
18 	struct adp5520_backlight_platform_data *pdata;
19 	struct mutex lock;
20 	unsigned long cached_daylight_max;
21 	int id;
22 	int current_brightness;
23 };
24 
25 static int adp5520_bl_set(struct backlight_device *bl, int brightness)
26 {
27 	struct adp5520_bl *data = bl_get_data(bl);
28 	struct device *master = data->master;
29 	int ret = 0;
30 
31 	if (data->pdata->en_ambl_sens) {
32 		if ((brightness > 0) && (brightness < ADP5020_MAX_BRIGHTNESS)) {
33 			/* Disable Ambient Light auto adjust */
34 			ret |= adp5520_clr_bits(master, ADP5520_BL_CONTROL,
35 					ADP5520_BL_AUTO_ADJ);
36 			ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
37 					brightness);
38 		} else {
39 			/*
40 			 * MAX_BRIGHTNESS -> Enable Ambient Light auto adjust
41 			 * restore daylight l3 sysfs brightness
42 			 */
43 			ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
44 					 data->cached_daylight_max);
45 			ret |= adp5520_set_bits(master, ADP5520_BL_CONTROL,
46 					 ADP5520_BL_AUTO_ADJ);
47 		}
48 	} else {
49 		ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX, brightness);
50 	}
51 
52 	if (data->current_brightness && brightness == 0)
53 		ret |= adp5520_set_bits(master,
54 				ADP5520_MODE_STATUS, ADP5520_DIM_EN);
55 	else if (data->current_brightness == 0 && brightness)
56 		ret |= adp5520_clr_bits(master,
57 				ADP5520_MODE_STATUS, ADP5520_DIM_EN);
58 
59 	if (!ret)
60 		data->current_brightness = brightness;
61 
62 	return ret;
63 }
64 
65 static int adp5520_bl_update_status(struct backlight_device *bl)
66 {
67 	int brightness = bl->props.brightness;
68 	if (bl->props.power != FB_BLANK_UNBLANK)
69 		brightness = 0;
70 
71 	if (bl->props.fb_blank != FB_BLANK_UNBLANK)
72 		brightness = 0;
73 
74 	return adp5520_bl_set(bl, brightness);
75 }
76 
77 static int adp5520_bl_get_brightness(struct backlight_device *bl)
78 {
79 	struct adp5520_bl *data = bl_get_data(bl);
80 	int error;
81 	uint8_t reg_val;
82 
83 	error = adp5520_read(data->master, ADP5520_BL_VALUE, &reg_val);
84 
85 	return error ? data->current_brightness : reg_val;
86 }
87 
88 static const struct backlight_ops adp5520_bl_ops = {
89 	.update_status	= adp5520_bl_update_status,
90 	.get_brightness	= adp5520_bl_get_brightness,
91 };
92 
93 static int adp5520_bl_setup(struct backlight_device *bl)
94 {
95 	struct adp5520_bl *data = bl_get_data(bl);
96 	struct device *master = data->master;
97 	struct adp5520_backlight_platform_data *pdata = data->pdata;
98 	int ret = 0;
99 
100 	ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
101 				pdata->l1_daylight_max);
102 	ret |= adp5520_write(master, ADP5520_DAYLIGHT_DIM,
103 				pdata->l1_daylight_dim);
104 
105 	if (pdata->en_ambl_sens) {
106 		data->cached_daylight_max = pdata->l1_daylight_max;
107 		ret |= adp5520_write(master, ADP5520_OFFICE_MAX,
108 				pdata->l2_office_max);
109 		ret |= adp5520_write(master, ADP5520_OFFICE_DIM,
110 				pdata->l2_office_dim);
111 		ret |= adp5520_write(master, ADP5520_DARK_MAX,
112 				pdata->l3_dark_max);
113 		ret |= adp5520_write(master, ADP5520_DARK_DIM,
114 				pdata->l3_dark_dim);
115 		ret |= adp5520_write(master, ADP5520_L2_TRIP,
116 				pdata->l2_trip);
117 		ret |= adp5520_write(master, ADP5520_L2_HYS,
118 				pdata->l2_hyst);
119 		ret |= adp5520_write(master, ADP5520_L3_TRIP,
120 				 pdata->l3_trip);
121 		ret |= adp5520_write(master, ADP5520_L3_HYS,
122 				pdata->l3_hyst);
123 		ret |= adp5520_write(master, ADP5520_ALS_CMPR_CFG,
124 				ALS_CMPR_CFG_VAL(pdata->abml_filt,
125 				ADP5520_L3_EN));
126 	}
127 
128 	ret |= adp5520_write(master, ADP5520_BL_CONTROL,
129 			BL_CTRL_VAL(pdata->fade_led_law,
130 					pdata->en_ambl_sens));
131 
132 	ret |= adp5520_write(master, ADP5520_BL_FADE, FADE_VAL(pdata->fade_in,
133 			pdata->fade_out));
134 
135 	ret |= adp5520_set_bits(master, ADP5520_MODE_STATUS,
136 			ADP5520_BL_EN | ADP5520_DIM_EN);
137 
138 	return ret;
139 }
140 
141 static ssize_t adp5520_show(struct device *dev, char *buf, int reg)
142 {
143 	struct adp5520_bl *data = dev_get_drvdata(dev);
144 	int error;
145 	uint8_t reg_val;
146 
147 	mutex_lock(&data->lock);
148 	error = adp5520_read(data->master, reg, &reg_val);
149 	mutex_unlock(&data->lock);
150 
151 	return sprintf(buf, "%u\n", reg_val);
152 }
153 
154 static ssize_t adp5520_store(struct device *dev, const char *buf,
155 			 size_t count, int reg)
156 {
157 	struct adp5520_bl *data = dev_get_drvdata(dev);
158 	unsigned long val;
159 	int ret;
160 
161 	ret = strict_strtoul(buf, 10, &val);
162 	if (ret)
163 		return ret;
164 
165 	mutex_lock(&data->lock);
166 	adp5520_write(data->master, reg, val);
167 	mutex_unlock(&data->lock);
168 
169 	return count;
170 }
171 
172 static ssize_t adp5520_bl_dark_max_show(struct device *dev,
173 			struct device_attribute *attr, char *buf)
174 {
175 	return adp5520_show(dev, buf, ADP5520_DARK_MAX);
176 }
177 
178 static ssize_t adp5520_bl_dark_max_store(struct device *dev,
179 			struct device_attribute *attr,
180 			const char *buf, size_t count)
181 {
182 	return adp5520_store(dev, buf, count, ADP5520_DARK_MAX);
183 }
184 static DEVICE_ATTR(dark_max, 0664, adp5520_bl_dark_max_show,
185 			adp5520_bl_dark_max_store);
186 
187 static ssize_t adp5520_bl_office_max_show(struct device *dev,
188 			struct device_attribute *attr, char *buf)
189 {
190 	return adp5520_show(dev, buf, ADP5520_OFFICE_MAX);
191 }
192 
193 static ssize_t adp5520_bl_office_max_store(struct device *dev,
194 			struct device_attribute *attr,
195 			const char *buf, size_t count)
196 {
197 	return adp5520_store(dev, buf, count, ADP5520_OFFICE_MAX);
198 }
199 static DEVICE_ATTR(office_max, 0664, adp5520_bl_office_max_show,
200 			adp5520_bl_office_max_store);
201 
202 static ssize_t adp5520_bl_daylight_max_show(struct device *dev,
203 			struct device_attribute *attr, char *buf)
204 {
205 	return adp5520_show(dev, buf, ADP5520_DAYLIGHT_MAX);
206 }
207 
208 static ssize_t adp5520_bl_daylight_max_store(struct device *dev,
209 			struct device_attribute *attr,
210 			const char *buf, size_t count)
211 {
212 	struct adp5520_bl *data = dev_get_drvdata(dev);
213 
214 	strict_strtoul(buf, 10, &data->cached_daylight_max);
215 	return adp5520_store(dev, buf, count, ADP5520_DAYLIGHT_MAX);
216 }
217 static DEVICE_ATTR(daylight_max, 0664, adp5520_bl_daylight_max_show,
218 			adp5520_bl_daylight_max_store);
219 
220 static ssize_t adp5520_bl_dark_dim_show(struct device *dev,
221 			struct device_attribute *attr, char *buf)
222 {
223 	return adp5520_show(dev, buf, ADP5520_DARK_DIM);
224 }
225 
226 static ssize_t adp5520_bl_dark_dim_store(struct device *dev,
227 			struct device_attribute *attr,
228 			const char *buf, size_t count)
229 {
230 	return adp5520_store(dev, buf, count, ADP5520_DARK_DIM);
231 }
232 static DEVICE_ATTR(dark_dim, 0664, adp5520_bl_dark_dim_show,
233 			adp5520_bl_dark_dim_store);
234 
235 static ssize_t adp5520_bl_office_dim_show(struct device *dev,
236 			struct device_attribute *attr, char *buf)
237 {
238 	return adp5520_show(dev, buf, ADP5520_OFFICE_DIM);
239 }
240 
241 static ssize_t adp5520_bl_office_dim_store(struct device *dev,
242 			struct device_attribute *attr,
243 			const char *buf, size_t count)
244 {
245 	return adp5520_store(dev, buf, count, ADP5520_OFFICE_DIM);
246 }
247 static DEVICE_ATTR(office_dim, 0664, adp5520_bl_office_dim_show,
248 			adp5520_bl_office_dim_store);
249 
250 static ssize_t adp5520_bl_daylight_dim_show(struct device *dev,
251 			struct device_attribute *attr, char *buf)
252 {
253 	return adp5520_show(dev, buf, ADP5520_DAYLIGHT_DIM);
254 }
255 
256 static ssize_t adp5520_bl_daylight_dim_store(struct device *dev,
257 			struct device_attribute *attr,
258 			const char *buf, size_t count)
259 {
260 	return adp5520_store(dev, buf, count, ADP5520_DAYLIGHT_DIM);
261 }
262 static DEVICE_ATTR(daylight_dim, 0664, adp5520_bl_daylight_dim_show,
263 			adp5520_bl_daylight_dim_store);
264 
265 static struct attribute *adp5520_bl_attributes[] = {
266 	&dev_attr_dark_max.attr,
267 	&dev_attr_dark_dim.attr,
268 	&dev_attr_office_max.attr,
269 	&dev_attr_office_dim.attr,
270 	&dev_attr_daylight_max.attr,
271 	&dev_attr_daylight_dim.attr,
272 	NULL
273 };
274 
275 static const struct attribute_group adp5520_bl_attr_group = {
276 	.attrs = adp5520_bl_attributes,
277 };
278 
279 static int __devinit adp5520_bl_probe(struct platform_device *pdev)
280 {
281 	struct backlight_device *bl;
282 	struct adp5520_bl *data;
283 	int ret = 0;
284 
285 	data = kzalloc(sizeof(*data), GFP_KERNEL);
286 	if (data == NULL)
287 		return -ENOMEM;
288 
289 	data->master = pdev->dev.parent;
290 	data->pdata = pdev->dev.platform_data;
291 
292 	if (data->pdata  == NULL) {
293 		dev_err(&pdev->dev, "missing platform data\n");
294 		kfree(data);
295 		return -ENODEV;
296 	}
297 
298 	data->id = pdev->id;
299 	data->current_brightness = 0;
300 
301 	mutex_init(&data->lock);
302 
303 	bl = backlight_device_register(pdev->name, data->master,
304 			data, &adp5520_bl_ops);
305 	if (IS_ERR(bl)) {
306 		dev_err(&pdev->dev, "failed to register backlight\n");
307 		kfree(data);
308 		return PTR_ERR(bl);
309 	}
310 
311 	bl->props.max_brightness =
312 		bl->props.brightness = ADP5020_MAX_BRIGHTNESS;
313 
314 	if (data->pdata->en_ambl_sens)
315 		ret = sysfs_create_group(&bl->dev.kobj,
316 			&adp5520_bl_attr_group);
317 
318 	if (ret) {
319 		dev_err(&pdev->dev, "failed to register sysfs\n");
320 		backlight_device_unregister(bl);
321 		kfree(data);
322 	}
323 
324 	platform_set_drvdata(pdev, bl);
325 	ret |= adp5520_bl_setup(bl);
326 	backlight_update_status(bl);
327 
328 	return ret;
329 }
330 
331 static int __devexit adp5520_bl_remove(struct platform_device *pdev)
332 {
333 	struct backlight_device *bl = platform_get_drvdata(pdev);
334 	struct adp5520_bl *data = bl_get_data(bl);
335 
336 	adp5520_clr_bits(data->master, ADP5520_MODE_STATUS, ADP5520_BL_EN);
337 
338 	if (data->pdata->en_ambl_sens)
339 		sysfs_remove_group(&bl->dev.kobj,
340 				&adp5520_bl_attr_group);
341 
342 	backlight_device_unregister(bl);
343 	kfree(data);
344 
345 	return 0;
346 }
347 
348 #ifdef CONFIG_PM
349 static int adp5520_bl_suspend(struct platform_device *pdev,
350 				 pm_message_t state)
351 {
352 	struct backlight_device *bl = platform_get_drvdata(pdev);
353 	return adp5520_bl_set(bl, 0);
354 }
355 
356 static int adp5520_bl_resume(struct platform_device *pdev)
357 {
358 	struct backlight_device *bl = platform_get_drvdata(pdev);
359 
360 	backlight_update_status(bl);
361 	return 0;
362 }
363 #else
364 #define adp5520_bl_suspend	NULL
365 #define adp5520_bl_resume	NULL
366 #endif
367 
368 static struct platform_driver adp5520_bl_driver = {
369 	.driver		= {
370 		.name	= "adp5520-backlight",
371 		.owner	= THIS_MODULE,
372 	},
373 	.probe		= adp5520_bl_probe,
374 	.remove		= __devexit_p(adp5520_bl_remove),
375 	.suspend	= adp5520_bl_suspend,
376 	.resume		= adp5520_bl_resume,
377 };
378 
379 static int __init adp5520_bl_init(void)
380 {
381 	return platform_driver_register(&adp5520_bl_driver);
382 }
383 module_init(adp5520_bl_init);
384 
385 static void __exit adp5520_bl_exit(void)
386 {
387 	platform_driver_unregister(&adp5520_bl_driver);
388 }
389 module_exit(adp5520_bl_exit);
390 
391 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
392 MODULE_DESCRIPTION("ADP5520(01) Backlight Driver");
393 MODULE_LICENSE("GPL");
394 MODULE_ALIAS("platform:adp5520-backlight");
395