bnx2x: prevent race in statistics flow
[linux-2.6/btrfs-unstable.git] / drivers / video / backlight / adp5520_bl.c
blobdfb763e9147ff923676e9ff2778116e3677f61ea
1 /*
2 * Backlight driver for Analog Devices ADP5520/ADP5501 MFD PMICs
4 * Copyright 2009 Analog Devices Inc.
6 * Licensed under the GPL-2 or later.
7 */
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 #include <linux/slab.h>
16 #include <linux/module.h>
18 struct adp5520_bl {
19 struct device *master;
20 struct adp5520_backlight_platform_data *pdata;
21 struct mutex lock;
22 unsigned long cached_daylight_max;
23 int id;
24 int current_brightness;
27 static int adp5520_bl_set(struct backlight_device *bl, int brightness)
29 struct adp5520_bl *data = bl_get_data(bl);
30 struct device *master = data->master;
31 int ret = 0;
33 if (data->pdata->en_ambl_sens) {
34 if ((brightness > 0) && (brightness < ADP5020_MAX_BRIGHTNESS)) {
35 /* Disable Ambient Light auto adjust */
36 ret |= adp5520_clr_bits(master, ADP5520_BL_CONTROL,
37 ADP5520_BL_AUTO_ADJ);
38 ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
39 brightness);
40 } else {
42 * MAX_BRIGHTNESS -> Enable Ambient Light auto adjust
43 * restore daylight l3 sysfs brightness
45 ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
46 data->cached_daylight_max);
47 ret |= adp5520_set_bits(master, ADP5520_BL_CONTROL,
48 ADP5520_BL_AUTO_ADJ);
50 } else {
51 ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX, brightness);
54 if (data->current_brightness && brightness == 0)
55 ret |= adp5520_set_bits(master,
56 ADP5520_MODE_STATUS, ADP5520_DIM_EN);
57 else if (data->current_brightness == 0 && brightness)
58 ret |= adp5520_clr_bits(master,
59 ADP5520_MODE_STATUS, ADP5520_DIM_EN);
61 if (!ret)
62 data->current_brightness = brightness;
64 return ret;
67 static int adp5520_bl_update_status(struct backlight_device *bl)
69 int brightness = bl->props.brightness;
70 if (bl->props.power != FB_BLANK_UNBLANK)
71 brightness = 0;
73 if (bl->props.fb_blank != FB_BLANK_UNBLANK)
74 brightness = 0;
76 return adp5520_bl_set(bl, brightness);
79 static int adp5520_bl_get_brightness(struct backlight_device *bl)
81 struct adp5520_bl *data = bl_get_data(bl);
82 int error;
83 uint8_t reg_val;
85 error = adp5520_read(data->master, ADP5520_BL_VALUE, &reg_val);
87 return error ? data->current_brightness : reg_val;
90 static const struct backlight_ops adp5520_bl_ops = {
91 .update_status = adp5520_bl_update_status,
92 .get_brightness = adp5520_bl_get_brightness,
95 static int adp5520_bl_setup(struct backlight_device *bl)
97 struct adp5520_bl *data = bl_get_data(bl);
98 struct device *master = data->master;
99 struct adp5520_backlight_platform_data *pdata = data->pdata;
100 int ret = 0;
102 ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
103 pdata->l1_daylight_max);
104 ret |= adp5520_write(master, ADP5520_DAYLIGHT_DIM,
105 pdata->l1_daylight_dim);
107 if (pdata->en_ambl_sens) {
108 data->cached_daylight_max = pdata->l1_daylight_max;
109 ret |= adp5520_write(master, ADP5520_OFFICE_MAX,
110 pdata->l2_office_max);
111 ret |= adp5520_write(master, ADP5520_OFFICE_DIM,
112 pdata->l2_office_dim);
113 ret |= adp5520_write(master, ADP5520_DARK_MAX,
114 pdata->l3_dark_max);
115 ret |= adp5520_write(master, ADP5520_DARK_DIM,
116 pdata->l3_dark_dim);
117 ret |= adp5520_write(master, ADP5520_L2_TRIP,
118 pdata->l2_trip);
119 ret |= adp5520_write(master, ADP5520_L2_HYS,
120 pdata->l2_hyst);
121 ret |= adp5520_write(master, ADP5520_L3_TRIP,
122 pdata->l3_trip);
123 ret |= adp5520_write(master, ADP5520_L3_HYS,
124 pdata->l3_hyst);
125 ret |= adp5520_write(master, ADP5520_ALS_CMPR_CFG,
126 ALS_CMPR_CFG_VAL(pdata->abml_filt,
127 ADP5520_L3_EN));
130 ret |= adp5520_write(master, ADP5520_BL_CONTROL,
131 BL_CTRL_VAL(pdata->fade_led_law,
132 pdata->en_ambl_sens));
134 ret |= adp5520_write(master, ADP5520_BL_FADE, FADE_VAL(pdata->fade_in,
135 pdata->fade_out));
137 ret |= adp5520_set_bits(master, ADP5520_MODE_STATUS,
138 ADP5520_BL_EN | ADP5520_DIM_EN);
140 return ret;
143 static ssize_t adp5520_show(struct device *dev, char *buf, int reg)
145 struct adp5520_bl *data = dev_get_drvdata(dev);
146 int error;
147 uint8_t reg_val;
149 mutex_lock(&data->lock);
150 error = adp5520_read(data->master, reg, &reg_val);
151 mutex_unlock(&data->lock);
153 return sprintf(buf, "%u\n", reg_val);
156 static ssize_t adp5520_store(struct device *dev, const char *buf,
157 size_t count, int reg)
159 struct adp5520_bl *data = dev_get_drvdata(dev);
160 unsigned long val;
161 int ret;
163 ret = strict_strtoul(buf, 10, &val);
164 if (ret)
165 return ret;
167 mutex_lock(&data->lock);
168 adp5520_write(data->master, reg, val);
169 mutex_unlock(&data->lock);
171 return count;
174 static ssize_t adp5520_bl_dark_max_show(struct device *dev,
175 struct device_attribute *attr, char *buf)
177 return adp5520_show(dev, buf, ADP5520_DARK_MAX);
180 static ssize_t adp5520_bl_dark_max_store(struct device *dev,
181 struct device_attribute *attr,
182 const char *buf, size_t count)
184 return adp5520_store(dev, buf, count, ADP5520_DARK_MAX);
186 static DEVICE_ATTR(dark_max, 0664, adp5520_bl_dark_max_show,
187 adp5520_bl_dark_max_store);
189 static ssize_t adp5520_bl_office_max_show(struct device *dev,
190 struct device_attribute *attr, char *buf)
192 return adp5520_show(dev, buf, ADP5520_OFFICE_MAX);
195 static ssize_t adp5520_bl_office_max_store(struct device *dev,
196 struct device_attribute *attr,
197 const char *buf, size_t count)
199 return adp5520_store(dev, buf, count, ADP5520_OFFICE_MAX);
201 static DEVICE_ATTR(office_max, 0664, adp5520_bl_office_max_show,
202 adp5520_bl_office_max_store);
204 static ssize_t adp5520_bl_daylight_max_show(struct device *dev,
205 struct device_attribute *attr, char *buf)
207 return adp5520_show(dev, buf, ADP5520_DAYLIGHT_MAX);
210 static ssize_t adp5520_bl_daylight_max_store(struct device *dev,
211 struct device_attribute *attr,
212 const char *buf, size_t count)
214 struct adp5520_bl *data = dev_get_drvdata(dev);
215 int ret;
217 ret = strict_strtoul(buf, 10, &data->cached_daylight_max);
218 if (ret < 0)
219 return ret;
221 return adp5520_store(dev, buf, count, ADP5520_DAYLIGHT_MAX);
223 static DEVICE_ATTR(daylight_max, 0664, adp5520_bl_daylight_max_show,
224 adp5520_bl_daylight_max_store);
226 static ssize_t adp5520_bl_dark_dim_show(struct device *dev,
227 struct device_attribute *attr, char *buf)
229 return adp5520_show(dev, buf, ADP5520_DARK_DIM);
232 static ssize_t adp5520_bl_dark_dim_store(struct device *dev,
233 struct device_attribute *attr,
234 const char *buf, size_t count)
236 return adp5520_store(dev, buf, count, ADP5520_DARK_DIM);
238 static DEVICE_ATTR(dark_dim, 0664, adp5520_bl_dark_dim_show,
239 adp5520_bl_dark_dim_store);
241 static ssize_t adp5520_bl_office_dim_show(struct device *dev,
242 struct device_attribute *attr, char *buf)
244 return adp5520_show(dev, buf, ADP5520_OFFICE_DIM);
247 static ssize_t adp5520_bl_office_dim_store(struct device *dev,
248 struct device_attribute *attr,
249 const char *buf, size_t count)
251 return adp5520_store(dev, buf, count, ADP5520_OFFICE_DIM);
253 static DEVICE_ATTR(office_dim, 0664, adp5520_bl_office_dim_show,
254 adp5520_bl_office_dim_store);
256 static ssize_t adp5520_bl_daylight_dim_show(struct device *dev,
257 struct device_attribute *attr, char *buf)
259 return adp5520_show(dev, buf, ADP5520_DAYLIGHT_DIM);
262 static ssize_t adp5520_bl_daylight_dim_store(struct device *dev,
263 struct device_attribute *attr,
264 const char *buf, size_t count)
266 return adp5520_store(dev, buf, count, ADP5520_DAYLIGHT_DIM);
268 static DEVICE_ATTR(daylight_dim, 0664, adp5520_bl_daylight_dim_show,
269 adp5520_bl_daylight_dim_store);
271 static struct attribute *adp5520_bl_attributes[] = {
272 &dev_attr_dark_max.attr,
273 &dev_attr_dark_dim.attr,
274 &dev_attr_office_max.attr,
275 &dev_attr_office_dim.attr,
276 &dev_attr_daylight_max.attr,
277 &dev_attr_daylight_dim.attr,
278 NULL
281 static const struct attribute_group adp5520_bl_attr_group = {
282 .attrs = adp5520_bl_attributes,
285 static int __devinit adp5520_bl_probe(struct platform_device *pdev)
287 struct backlight_properties props;
288 struct backlight_device *bl;
289 struct adp5520_bl *data;
290 int ret = 0;
292 data = kzalloc(sizeof(*data), GFP_KERNEL);
293 if (data == NULL)
294 return -ENOMEM;
296 data->master = pdev->dev.parent;
297 data->pdata = pdev->dev.platform_data;
299 if (data->pdata == NULL) {
300 dev_err(&pdev->dev, "missing platform data\n");
301 kfree(data);
302 return -ENODEV;
305 data->id = pdev->id;
306 data->current_brightness = 0;
308 mutex_init(&data->lock);
310 memset(&props, 0, sizeof(struct backlight_properties));
311 props.type = BACKLIGHT_RAW;
312 props.max_brightness = ADP5020_MAX_BRIGHTNESS;
313 bl = backlight_device_register(pdev->name, data->master, data,
314 &adp5520_bl_ops, &props);
315 if (IS_ERR(bl)) {
316 dev_err(&pdev->dev, "failed to register backlight\n");
317 kfree(data);
318 return PTR_ERR(bl);
321 bl->props.brightness = ADP5020_MAX_BRIGHTNESS;
322 if (data->pdata->en_ambl_sens)
323 ret = sysfs_create_group(&bl->dev.kobj,
324 &adp5520_bl_attr_group);
326 if (ret) {
327 dev_err(&pdev->dev, "failed to register sysfs\n");
328 backlight_device_unregister(bl);
329 kfree(data);
332 platform_set_drvdata(pdev, bl);
333 ret |= adp5520_bl_setup(bl);
334 backlight_update_status(bl);
336 return ret;
339 static int __devexit adp5520_bl_remove(struct platform_device *pdev)
341 struct backlight_device *bl = platform_get_drvdata(pdev);
342 struct adp5520_bl *data = bl_get_data(bl);
344 adp5520_clr_bits(data->master, ADP5520_MODE_STATUS, ADP5520_BL_EN);
346 if (data->pdata->en_ambl_sens)
347 sysfs_remove_group(&bl->dev.kobj,
348 &adp5520_bl_attr_group);
350 backlight_device_unregister(bl);
351 kfree(data);
353 return 0;
356 #ifdef CONFIG_PM
357 static int adp5520_bl_suspend(struct platform_device *pdev,
358 pm_message_t state)
360 struct backlight_device *bl = platform_get_drvdata(pdev);
361 return adp5520_bl_set(bl, 0);
364 static int adp5520_bl_resume(struct platform_device *pdev)
366 struct backlight_device *bl = platform_get_drvdata(pdev);
368 backlight_update_status(bl);
369 return 0;
371 #else
372 #define adp5520_bl_suspend NULL
373 #define adp5520_bl_resume NULL
374 #endif
376 static struct platform_driver adp5520_bl_driver = {
377 .driver = {
378 .name = "adp5520-backlight",
379 .owner = THIS_MODULE,
381 .probe = adp5520_bl_probe,
382 .remove = __devexit_p(adp5520_bl_remove),
383 .suspend = adp5520_bl_suspend,
384 .resume = adp5520_bl_resume,
387 static int __init adp5520_bl_init(void)
389 return platform_driver_register(&adp5520_bl_driver);
391 module_init(adp5520_bl_init);
393 static void __exit adp5520_bl_exit(void)
395 platform_driver_unregister(&adp5520_bl_driver);
397 module_exit(adp5520_bl_exit);
399 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
400 MODULE_DESCRIPTION("ADP5520(01) Backlight Driver");
401 MODULE_LICENSE("GPL");
402 MODULE_ALIAS("platform:adp5520-backlight");