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_platfrom_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, BL_CONTROL,
35 					BL_AUTO_ADJ);
36 			ret |= adp5520_write(master, DAYLIGHT_MAX, brightness);
37 		} else {
38 			/*
39 			 * MAX_BRIGHTNESS -> Enable Ambient Light auto adjust
40 			 * restore daylight l3 sysfs brightness
41 			 */
42 			ret |= adp5520_write(master, DAYLIGHT_MAX,
43 					 data->cached_daylight_max);
44 			ret |= adp5520_set_bits(master, BL_CONTROL,
45 					 BL_AUTO_ADJ);
46 		}
47 	} else {
48 		ret |= adp5520_write(master, DAYLIGHT_MAX, brightness);
49 	}
50 
51 	if (data->current_brightness && brightness == 0)
52 		ret |= adp5520_set_bits(master,
53 				MODE_STATUS, DIM_EN);
54 	else if (data->current_brightness == 0 && brightness)
55 		ret |= adp5520_clr_bits(master,
56 				MODE_STATUS, DIM_EN);
57 
58 	if (!ret)
59 		data->current_brightness = brightness;
60 
61 	return ret;
62 }
63 
64 static int adp5520_bl_update_status(struct backlight_device *bl)
65 {
66 	int brightness = bl->props.brightness;
67 	if (bl->props.power != FB_BLANK_UNBLANK)
68 		brightness = 0;
69 
70 	if (bl->props.fb_blank != FB_BLANK_UNBLANK)
71 		brightness = 0;
72 
73 	return adp5520_bl_set(bl, brightness);
74 }
75 
76 static int adp5520_bl_get_brightness(struct backlight_device *bl)
77 {
78 	struct adp5520_bl *data = bl_get_data(bl);
79 	int error;
80 	uint8_t reg_val;
81 
82 	error = adp5520_read(data->master, BL_VALUE, &reg_val);
83 
84 	return error ? data->current_brightness : reg_val;
85 }
86 
87 static struct backlight_ops adp5520_bl_ops = {
88 	.update_status	= adp5520_bl_update_status,
89 	.get_brightness	= adp5520_bl_get_brightness,
90 };
91 
92 static int adp5520_bl_setup(struct backlight_device *bl)
93 {
94 	struct adp5520_bl *data = bl_get_data(bl);
95 	struct device *master = data->master;
96 	struct adp5520_backlight_platfrom_data *pdata = data->pdata;
97 	int ret = 0;
98 
99 	ret |= adp5520_write(master, DAYLIGHT_MAX, pdata->l1_daylight_max);
100 	ret |= adp5520_write(master, DAYLIGHT_DIM, pdata->l1_daylight_dim);
101 
102 	if (pdata->en_ambl_sens) {
103 		data->cached_daylight_max = pdata->l1_daylight_max;
104 		ret |= adp5520_write(master, OFFICE_MAX, pdata->l2_office_max);
105 		ret |= adp5520_write(master, OFFICE_DIM, pdata->l2_office_dim);
106 		ret |= adp5520_write(master, DARK_MAX, pdata->l3_dark_max);
107 		ret |= adp5520_write(master, DARK_DIM, pdata->l3_dark_dim);
108 		ret |= adp5520_write(master, L2_TRIP, pdata->l2_trip);
109 		ret |= adp5520_write(master, L2_HYS, pdata->l2_hyst);
110 		ret |= adp5520_write(master, L3_TRIP, pdata->l3_trip);
111 		ret |= adp5520_write(master, L3_HYS, pdata->l3_hyst);
112 		ret |= adp5520_write(master, ALS_CMPR_CFG,
113 			ALS_CMPR_CFG_VAL(pdata->abml_filt, L3_EN));
114 	}
115 
116 	ret |= adp5520_write(master, BL_CONTROL,
117 			BL_CTRL_VAL(pdata->fade_led_law, pdata->en_ambl_sens));
118 
119 	ret |= adp5520_write(master, BL_FADE, FADE_VAL(pdata->fade_in,
120 			pdata->fade_out));
121 
122 	ret |= adp5520_set_bits(master, MODE_STATUS, BL_EN | DIM_EN);
123 
124 	return ret;
125 }
126 
127 static ssize_t adp5520_show(struct device *dev, char *buf, int reg)
128 {
129 	struct adp5520_bl *data = dev_get_drvdata(dev);
130 	int error;
131 	uint8_t reg_val;
132 
133 	mutex_lock(&data->lock);
134 	error = adp5520_read(data->master, reg, &reg_val);
135 	mutex_unlock(&data->lock);
136 
137 	return sprintf(buf, "%u\n", reg_val);
138 }
139 
140 static ssize_t adp5520_store(struct device *dev, const char *buf,
141 			 size_t count, int reg)
142 {
143 	struct adp5520_bl *data = dev_get_drvdata(dev);
144 	unsigned long val;
145 	int ret;
146 
147 	ret = strict_strtoul(buf, 10, &val);
148 	if (ret)
149 		return ret;
150 
151 	mutex_lock(&data->lock);
152 	adp5520_write(data->master, reg, val);
153 	mutex_unlock(&data->lock);
154 
155 	return count;
156 }
157 
158 static ssize_t adp5520_bl_dark_max_show(struct device *dev,
159 		struct device_attribute *attr, char *buf)
160 {
161 	return adp5520_show(dev, buf, DARK_MAX);
162 }
163 
164 static ssize_t adp5520_bl_dark_max_store(struct device *dev,
165 		struct device_attribute *attr, const char *buf, size_t count)
166 {
167 	return adp5520_store(dev, buf, count, DARK_MAX);
168 }
169 static DEVICE_ATTR(dark_max, 0664, adp5520_bl_dark_max_show,
170 			adp5520_bl_dark_max_store);
171 
172 static ssize_t adp5520_bl_office_max_show(struct device *dev,
173 				     struct device_attribute *attr, char *buf)
174 {
175 	return adp5520_show(dev, buf, OFFICE_MAX);
176 }
177 
178 static ssize_t adp5520_bl_office_max_store(struct device *dev,
179 		struct device_attribute *attr, const char *buf, size_t count)
180 {
181 	return adp5520_store(dev, buf, count, OFFICE_MAX);
182 }
183 static DEVICE_ATTR(office_max, 0664, adp5520_bl_office_max_show,
184 			adp5520_bl_office_max_store);
185 
186 static ssize_t adp5520_bl_daylight_max_show(struct device *dev,
187 			struct device_attribute *attr, char *buf)
188 {
189 	return adp5520_show(dev, buf, DAYLIGHT_MAX);
190 }
191 
192 static ssize_t adp5520_bl_daylight_max_store(struct device *dev,
193 		struct device_attribute *attr, const char *buf, size_t count)
194 {
195 	struct adp5520_bl *data = dev_get_drvdata(dev);
196 
197 	strict_strtoul(buf, 10, &data->cached_daylight_max);
198 	return adp5520_store(dev, buf, count, DAYLIGHT_MAX);
199 }
200 static DEVICE_ATTR(daylight_max, 0664, adp5520_bl_daylight_max_show,
201 			adp5520_bl_daylight_max_store);
202 
203 static ssize_t adp5520_bl_dark_dim_show(struct device *dev,
204 			struct device_attribute *attr, char *buf)
205 {
206 	return adp5520_show(dev, buf, DARK_DIM);
207 }
208 
209 static ssize_t adp5520_bl_dark_dim_store(struct device *dev,
210 				     struct device_attribute *attr,
211 				     const char *buf, size_t count)
212 {
213 	return adp5520_store(dev, buf, count, DARK_DIM);
214 }
215 static DEVICE_ATTR(dark_dim, 0664, adp5520_bl_dark_dim_show,
216 			adp5520_bl_dark_dim_store);
217 
218 static ssize_t adp5520_bl_office_dim_show(struct device *dev,
219 			struct device_attribute *attr, char *buf)
220 {
221 	return adp5520_show(dev, buf, OFFICE_DIM);
222 }
223 
224 static ssize_t adp5520_bl_office_dim_store(struct device *dev,
225 				     struct device_attribute *attr,
226 				     const char *buf, size_t count)
227 {
228 	return adp5520_store(dev, buf, count, OFFICE_DIM);
229 }
230 static DEVICE_ATTR(office_dim, 0664, adp5520_bl_office_dim_show,
231 			adp5520_bl_office_dim_store);
232 
233 static ssize_t adp5520_bl_daylight_dim_show(struct device *dev,
234 				     struct device_attribute *attr, char *buf)
235 {
236 	return adp5520_show(dev, buf, DAYLIGHT_DIM);
237 }
238 
239 static ssize_t adp5520_bl_daylight_dim_store(struct device *dev,
240 				     struct device_attribute *attr,
241 				     const char *buf, size_t count)
242 {
243 	return adp5520_store(dev, buf, count, DAYLIGHT_DIM);
244 }
245 static DEVICE_ATTR(daylight_dim, 0664, adp5520_bl_daylight_dim_show,
246 			adp5520_bl_daylight_dim_store);
247 
248 static struct attribute *adp5520_bl_attributes[] = {
249 	&dev_attr_dark_max.attr,
250 	&dev_attr_dark_dim.attr,
251 	&dev_attr_office_max.attr,
252 	&dev_attr_office_dim.attr,
253 	&dev_attr_daylight_max.attr,
254 	&dev_attr_daylight_dim.attr,
255 	NULL
256 };
257 
258 static const struct attribute_group adp5520_bl_attr_group = {
259 	.attrs = adp5520_bl_attributes,
260 };
261 
262 static int __devinit adp5520_bl_probe(struct platform_device *pdev)
263 {
264 	struct backlight_device *bl;
265 	struct adp5520_bl *data;
266 	int ret = 0;
267 
268 	data = kzalloc(sizeof(*data), GFP_KERNEL);
269 	if (data == NULL)
270 		return -ENOMEM;
271 
272 	data->master = pdev->dev.parent;
273 	data->pdata = pdev->dev.platform_data;
274 
275 	if (data->pdata  == NULL) {
276 		dev_err(&pdev->dev, "missing platform data\n");
277 		kfree(data);
278 		return -ENODEV;
279 	}
280 
281 	data->id = pdev->id;
282 	data->current_brightness = 0;
283 
284 	mutex_init(&data->lock);
285 
286 	bl = backlight_device_register(pdev->name, data->master,
287 			data, &adp5520_bl_ops);
288 	if (IS_ERR(bl)) {
289 		dev_err(&pdev->dev, "failed to register backlight\n");
290 		kfree(data);
291 		return PTR_ERR(bl);
292 	}
293 
294 	bl->props.max_brightness =
295 		bl->props.brightness = ADP5020_MAX_BRIGHTNESS;
296 
297 	if (data->pdata->en_ambl_sens)
298 		ret = sysfs_create_group(&bl->dev.kobj,
299 			&adp5520_bl_attr_group);
300 
301 	if (ret) {
302 		dev_err(&pdev->dev, "failed to register sysfs\n");
303 		backlight_device_unregister(bl);
304 		kfree(data);
305 	}
306 
307 	platform_set_drvdata(pdev, bl);
308 	ret |= adp5520_bl_setup(bl);
309 	backlight_update_status(bl);
310 
311 	return ret;
312 }
313 
314 static int __devexit adp5520_bl_remove(struct platform_device *pdev)
315 {
316 	struct backlight_device *bl = platform_get_drvdata(pdev);
317 	struct adp5520_bl *data = bl_get_data(bl);
318 
319 	adp5520_clr_bits(data->master, MODE_STATUS, BL_EN);
320 
321 	if (data->pdata->en_ambl_sens)
322 		sysfs_remove_group(&bl->dev.kobj,
323 				&adp5520_bl_attr_group);
324 
325 	backlight_device_unregister(bl);
326 	kfree(data);
327 
328 	return 0;
329 }
330 
331 #ifdef CONFIG_PM
332 static int adp5520_bl_suspend(struct platform_device *pdev,
333 				 pm_message_t state)
334 {
335 	struct backlight_device *bl = platform_get_drvdata(pdev);
336 	return adp5520_bl_set(bl, 0);
337 }
338 
339 static int adp5520_bl_resume(struct platform_device *pdev)
340 {
341 	struct backlight_device *bl = platform_get_drvdata(pdev);
342 
343 	backlight_update_status(bl);
344 	return 0;
345 }
346 #else
347 #define adp5520_bl_suspend	NULL
348 #define adp5520_bl_resume	NULL
349 #endif
350 
351 static struct platform_driver adp5520_bl_driver = {
352 	.driver		= {
353 		.name	= "adp5520-backlight",
354 		.owner	= THIS_MODULE,
355 	},
356 	.probe		= adp5520_bl_probe,
357 	.remove		= __devexit_p(adp5520_bl_remove),
358 	.suspend	= adp5520_bl_suspend,
359 	.resume		= adp5520_bl_resume,
360 };
361 
362 static int __init adp5520_bl_init(void)
363 {
364 	return platform_driver_register(&adp5520_bl_driver);
365 }
366 module_init(adp5520_bl_init);
367 
368 static void __exit adp5520_bl_exit(void)
369 {
370 	platform_driver_unregister(&adp5520_bl_driver);
371 }
372 module_exit(adp5520_bl_exit);
373 
374 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
375 MODULE_DESCRIPTION("ADP5520(01) Backlight Driver");
376 MODULE_LICENSE("GPL");
377 MODULE_ALIAS("platform:adp5520-backlight");
378