Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Backlight Lowlevel Control Abstraction | |
3 | * | |
4 | * Copyright (C) 2003,2004 Hewlett-Packard Company | |
5 | * | |
6 | */ | |
7 | ||
1da177e4 LT |
8 | #include <linux/module.h> |
9 | #include <linux/init.h> | |
10 | #include <linux/device.h> | |
11 | #include <linux/backlight.h> | |
12 | #include <linux/notifier.h> | |
13 | #include <linux/ctype.h> | |
14 | #include <linux/err.h> | |
15 | #include <linux/fb.h> | |
5a0e3ad6 | 16 | #include <linux/slab.h> |
1da177e4 | 17 | |
321709c5 RP |
18 | #ifdef CONFIG_PMAC_BACKLIGHT |
19 | #include <asm/backlight.h> | |
20 | #endif | |
3d5eeadd JS |
21 | |
22 | #if defined(CONFIG_FB) || (defined(CONFIG_FB_MODULE) && \ | |
23 | defined(CONFIG_BACKLIGHT_CLASS_DEVICE_MODULE)) | |
24 | /* This callback gets called when something important happens inside a | |
25 | * framebuffer driver. We're looking if that important event is blanking, | |
26 | * and if it is, we're switching backlight power as well ... | |
27 | */ | |
28 | static int fb_notifier_callback(struct notifier_block *self, | |
29 | unsigned long event, void *data) | |
30 | { | |
31 | struct backlight_device *bd; | |
32 | struct fb_event *evdata = data; | |
33 | ||
34 | /* If we aren't interested in this event, skip it immediately ... */ | |
994efacd | 35 | if (event != FB_EVENT_BLANK && event != FB_EVENT_CONBLANK) |
3d5eeadd JS |
36 | return 0; |
37 | ||
38 | bd = container_of(self, struct backlight_device, fb_notif); | |
599a52d1 RP |
39 | mutex_lock(&bd->ops_lock); |
40 | if (bd->ops) | |
41 | if (!bd->ops->check_fb || | |
57e148b6 | 42 | bd->ops->check_fb(bd, evdata->info)) { |
599a52d1 | 43 | bd->props.fb_blank = *(int *)evdata->data; |
c835ee7f RP |
44 | if (bd->props.fb_blank == FB_BLANK_UNBLANK) |
45 | bd->props.state &= ~BL_CORE_FBBLANK; | |
46 | else | |
47 | bd->props.state |= BL_CORE_FBBLANK; | |
28ee086d | 48 | backlight_update_status(bd); |
3d5eeadd | 49 | } |
599a52d1 | 50 | mutex_unlock(&bd->ops_lock); |
3d5eeadd JS |
51 | return 0; |
52 | } | |
53 | ||
54 | static int backlight_register_fb(struct backlight_device *bd) | |
55 | { | |
56 | memset(&bd->fb_notif, 0, sizeof(bd->fb_notif)); | |
57 | bd->fb_notif.notifier_call = fb_notifier_callback; | |
58 | ||
59 | return fb_register_client(&bd->fb_notif); | |
60 | } | |
61 | ||
62 | static void backlight_unregister_fb(struct backlight_device *bd) | |
63 | { | |
64 | fb_unregister_client(&bd->fb_notif); | |
65 | } | |
66 | #else | |
67 | static inline int backlight_register_fb(struct backlight_device *bd) | |
68 | { | |
69 | return 0; | |
70 | } | |
71 | ||
72 | static inline void backlight_unregister_fb(struct backlight_device *bd) | |
73 | { | |
74 | } | |
75 | #endif /* CONFIG_FB */ | |
76 | ||
325253a6 MG |
77 | static void backlight_generate_event(struct backlight_device *bd, |
78 | enum backlight_update_reason reason) | |
79 | { | |
80 | char *envp[2]; | |
81 | ||
82 | switch (reason) { | |
83 | case BACKLIGHT_UPDATE_SYSFS: | |
84 | envp[0] = "SOURCE=sysfs"; | |
85 | break; | |
86 | case BACKLIGHT_UPDATE_HOTKEY: | |
87 | envp[0] = "SOURCE=hotkey"; | |
88 | break; | |
89 | default: | |
90 | envp[0] = "SOURCE=unknown"; | |
91 | break; | |
92 | } | |
93 | envp[1] = NULL; | |
94 | kobject_uevent_env(&bd->dev.kobj, KOBJ_CHANGE, envp); | |
89dfc28c | 95 | sysfs_notify(&bd->dev.kobj, NULL, "actual_brightness"); |
325253a6 MG |
96 | } |
97 | ||
655bfd7a RP |
98 | static ssize_t backlight_show_power(struct device *dev, |
99 | struct device_attribute *attr,char *buf) | |
1da177e4 | 100 | { |
655bfd7a | 101 | struct backlight_device *bd = to_backlight_device(dev); |
1da177e4 | 102 | |
599a52d1 | 103 | return sprintf(buf, "%d\n", bd->props.power); |
1da177e4 LT |
104 | } |
105 | ||
655bfd7a RP |
106 | static ssize_t backlight_store_power(struct device *dev, |
107 | struct device_attribute *attr, const char *buf, size_t count) | |
1da177e4 | 108 | { |
9a2c61a9 | 109 | int rc; |
655bfd7a | 110 | struct backlight_device *bd = to_backlight_device(dev); |
9a2c61a9 | 111 | unsigned long power; |
1da177e4 | 112 | |
9a2c61a9 PM |
113 | rc = strict_strtoul(buf, 0, &power); |
114 | if (rc) | |
115 | return rc; | |
1da177e4 | 116 | |
9a2c61a9 | 117 | rc = -ENXIO; |
599a52d1 RP |
118 | mutex_lock(&bd->ops_lock); |
119 | if (bd->ops) { | |
9a2c61a9 | 120 | pr_debug("backlight: set power to %lu\n", power); |
51552453 HD |
121 | if (bd->props.power != power) { |
122 | bd->props.power = power; | |
123 | backlight_update_status(bd); | |
124 | } | |
1da177e4 | 125 | rc = count; |
6ca01765 | 126 | } |
599a52d1 | 127 | mutex_unlock(&bd->ops_lock); |
1da177e4 LT |
128 | |
129 | return rc; | |
130 | } | |
131 | ||
655bfd7a RP |
132 | static ssize_t backlight_show_brightness(struct device *dev, |
133 | struct device_attribute *attr, char *buf) | |
1da177e4 | 134 | { |
655bfd7a | 135 | struct backlight_device *bd = to_backlight_device(dev); |
1da177e4 | 136 | |
599a52d1 | 137 | return sprintf(buf, "%d\n", bd->props.brightness); |
1da177e4 LT |
138 | } |
139 | ||
655bfd7a RP |
140 | static ssize_t backlight_store_brightness(struct device *dev, |
141 | struct device_attribute *attr, const char *buf, size_t count) | |
1da177e4 | 142 | { |
9a2c61a9 | 143 | int rc; |
655bfd7a | 144 | struct backlight_device *bd = to_backlight_device(dev); |
9a2c61a9 | 145 | unsigned long brightness; |
1da177e4 | 146 | |
9a2c61a9 PM |
147 | rc = strict_strtoul(buf, 0, &brightness); |
148 | if (rc) | |
149 | return rc; | |
150 | ||
151 | rc = -ENXIO; | |
1da177e4 | 152 | |
599a52d1 RP |
153 | mutex_lock(&bd->ops_lock); |
154 | if (bd->ops) { | |
155 | if (brightness > bd->props.max_brightness) | |
6ca01765 RP |
156 | rc = -EINVAL; |
157 | else { | |
9a2c61a9 | 158 | pr_debug("backlight: set brightness to %lu\n", |
6ca01765 | 159 | brightness); |
9be1df98 ZR |
160 | bd->props.brightness = brightness; |
161 | backlight_update_status(bd); | |
6ca01765 RP |
162 | rc = count; |
163 | } | |
164 | } | |
599a52d1 | 165 | mutex_unlock(&bd->ops_lock); |
1da177e4 | 166 | |
325253a6 MG |
167 | backlight_generate_event(bd, BACKLIGHT_UPDATE_SYSFS); |
168 | ||
1da177e4 LT |
169 | return rc; |
170 | } | |
171 | ||
655bfd7a RP |
172 | static ssize_t backlight_show_max_brightness(struct device *dev, |
173 | struct device_attribute *attr, char *buf) | |
1da177e4 | 174 | { |
655bfd7a | 175 | struct backlight_device *bd = to_backlight_device(dev); |
1da177e4 | 176 | |
599a52d1 | 177 | return sprintf(buf, "%d\n", bd->props.max_brightness); |
6ca01765 RP |
178 | } |
179 | ||
655bfd7a RP |
180 | static ssize_t backlight_show_actual_brightness(struct device *dev, |
181 | struct device_attribute *attr, char *buf) | |
6ca01765 RP |
182 | { |
183 | int rc = -ENXIO; | |
655bfd7a | 184 | struct backlight_device *bd = to_backlight_device(dev); |
6ca01765 | 185 | |
599a52d1 RP |
186 | mutex_lock(&bd->ops_lock); |
187 | if (bd->ops && bd->ops->get_brightness) | |
188 | rc = sprintf(buf, "%d\n", bd->ops->get_brightness(bd)); | |
189 | mutex_unlock(&bd->ops_lock); | |
1da177e4 LT |
190 | |
191 | return rc; | |
192 | } | |
193 | ||
0ad90efd | 194 | static struct class *backlight_class; |
655bfd7a | 195 | |
c835ee7f RP |
196 | static int backlight_suspend(struct device *dev, pm_message_t state) |
197 | { | |
198 | struct backlight_device *bd = to_backlight_device(dev); | |
199 | ||
d1d73578 UKK |
200 | mutex_lock(&bd->ops_lock); |
201 | if (bd->ops && bd->ops->options & BL_CORE_SUSPENDRESUME) { | |
c835ee7f RP |
202 | bd->props.state |= BL_CORE_SUSPENDED; |
203 | backlight_update_status(bd); | |
c835ee7f | 204 | } |
d1d73578 | 205 | mutex_unlock(&bd->ops_lock); |
c835ee7f RP |
206 | |
207 | return 0; | |
208 | } | |
209 | ||
210 | static int backlight_resume(struct device *dev) | |
211 | { | |
212 | struct backlight_device *bd = to_backlight_device(dev); | |
213 | ||
d1d73578 UKK |
214 | mutex_lock(&bd->ops_lock); |
215 | if (bd->ops && bd->ops->options & BL_CORE_SUSPENDRESUME) { | |
c835ee7f RP |
216 | bd->props.state &= ~BL_CORE_SUSPENDED; |
217 | backlight_update_status(bd); | |
c835ee7f | 218 | } |
d1d73578 | 219 | mutex_unlock(&bd->ops_lock); |
c835ee7f RP |
220 | |
221 | return 0; | |
222 | } | |
223 | ||
655bfd7a | 224 | static void bl_device_release(struct device *dev) |
1da177e4 LT |
225 | { |
226 | struct backlight_device *bd = to_backlight_device(dev); | |
227 | kfree(bd); | |
228 | } | |
229 | ||
655bfd7a RP |
230 | static struct device_attribute bl_device_attributes[] = { |
231 | __ATTR(bl_power, 0644, backlight_show_power, backlight_store_power), | |
232 | __ATTR(brightness, 0644, backlight_show_brightness, | |
6ca01765 | 233 | backlight_store_brightness), |
655bfd7a | 234 | __ATTR(actual_brightness, 0444, backlight_show_actual_brightness, |
6ca01765 | 235 | NULL), |
655bfd7a RP |
236 | __ATTR(max_brightness, 0444, backlight_show_max_brightness, NULL), |
237 | __ATTR_NULL, | |
1da177e4 LT |
238 | }; |
239 | ||
325253a6 MG |
240 | /** |
241 | * backlight_force_update - tell the backlight subsystem that hardware state | |
242 | * has changed | |
243 | * @bd: the backlight device to update | |
244 | * | |
245 | * Updates the internal state of the backlight in response to a hardware event, | |
246 | * and generate a uevent to notify userspace | |
247 | */ | |
248 | void backlight_force_update(struct backlight_device *bd, | |
249 | enum backlight_update_reason reason) | |
250 | { | |
251 | mutex_lock(&bd->ops_lock); | |
252 | if (bd->ops && bd->ops->get_brightness) | |
253 | bd->props.brightness = bd->ops->get_brightness(bd); | |
254 | mutex_unlock(&bd->ops_lock); | |
255 | backlight_generate_event(bd, reason); | |
256 | } | |
257 | EXPORT_SYMBOL(backlight_force_update); | |
258 | ||
1da177e4 LT |
259 | /** |
260 | * backlight_device_register - create and register a new object of | |
261 | * backlight_device class. | |
262 | * @name: the name of the new object(must be the same as the name of the | |
263 | * respective framebuffer device). | |
f6ec2d96 | 264 | * @parent: a pointer to the parent device |
655bfd7a RP |
265 | * @devdata: an optional pointer to be stored for private driver use. The |
266 | * methods may retrieve it by using bl_get_data(bd). | |
599a52d1 | 267 | * @ops: the backlight operations structure. |
1da177e4 | 268 | * |
655bfd7a | 269 | * Creates and registers new backlight device. Returns either an |
1da177e4 LT |
270 | * ERR_PTR() or a pointer to the newly allocated device. |
271 | */ | |
519ab5f2 | 272 | struct backlight_device *backlight_device_register(const char *name, |
a19a6ee6 MG |
273 | struct device *parent, void *devdata, const struct backlight_ops *ops, |
274 | const struct backlight_properties *props) | |
1da177e4 | 275 | { |
1da177e4 | 276 | struct backlight_device *new_bd; |
655bfd7a | 277 | int rc; |
1da177e4 | 278 | |
655bfd7a | 279 | pr_debug("backlight_device_register: name=%s\n", name); |
1da177e4 | 280 | |
599a52d1 | 281 | new_bd = kzalloc(sizeof(struct backlight_device), GFP_KERNEL); |
90968e8e | 282 | if (!new_bd) |
10ad1b73 | 283 | return ERR_PTR(-ENOMEM); |
1da177e4 | 284 | |
28ee086d | 285 | mutex_init(&new_bd->update_lock); |
599a52d1 | 286 | mutex_init(&new_bd->ops_lock); |
1da177e4 | 287 | |
655bfd7a RP |
288 | new_bd->dev.class = backlight_class; |
289 | new_bd->dev.parent = parent; | |
290 | new_bd->dev.release = bl_device_release; | |
64dba9a9 | 291 | dev_set_name(&new_bd->dev, name); |
655bfd7a RP |
292 | dev_set_drvdata(&new_bd->dev, devdata); |
293 | ||
a19a6ee6 MG |
294 | /* Set default properties */ |
295 | if (props) | |
296 | memcpy(&new_bd->props, props, | |
297 | sizeof(struct backlight_properties)); | |
298 | ||
655bfd7a | 299 | rc = device_register(&new_bd->dev); |
90968e8e | 300 | if (rc) { |
2fd5a154 | 301 | kfree(new_bd); |
1da177e4 LT |
302 | return ERR_PTR(rc); |
303 | } | |
304 | ||
3d5eeadd | 305 | rc = backlight_register_fb(new_bd); |
2fd5a154 | 306 | if (rc) { |
655bfd7a | 307 | device_unregister(&new_bd->dev); |
2fd5a154 DT |
308 | return ERR_PTR(rc); |
309 | } | |
310 | ||
655bfd7a | 311 | new_bd->ops = ops; |
1da177e4 | 312 | |
321709c5 RP |
313 | #ifdef CONFIG_PMAC_BACKLIGHT |
314 | mutex_lock(&pmac_backlight_mutex); | |
315 | if (!pmac_backlight) | |
316 | pmac_backlight = new_bd; | |
317 | mutex_unlock(&pmac_backlight_mutex); | |
318 | #endif | |
319 | ||
1da177e4 LT |
320 | return new_bd; |
321 | } | |
322 | EXPORT_SYMBOL(backlight_device_register); | |
323 | ||
324 | /** | |
325 | * backlight_device_unregister - unregisters a backlight device object. | |
326 | * @bd: the backlight device object to be unregistered and freed. | |
327 | * | |
328 | * Unregisters a previously registered via backlight_device_register object. | |
329 | */ | |
330 | void backlight_device_unregister(struct backlight_device *bd) | |
331 | { | |
1da177e4 LT |
332 | if (!bd) |
333 | return; | |
334 | ||
321709c5 RP |
335 | #ifdef CONFIG_PMAC_BACKLIGHT |
336 | mutex_lock(&pmac_backlight_mutex); | |
337 | if (pmac_backlight == bd) | |
338 | pmac_backlight = NULL; | |
339 | mutex_unlock(&pmac_backlight_mutex); | |
340 | #endif | |
599a52d1 RP |
341 | mutex_lock(&bd->ops_lock); |
342 | bd->ops = NULL; | |
343 | mutex_unlock(&bd->ops_lock); | |
1da177e4 | 344 | |
3d5eeadd | 345 | backlight_unregister_fb(bd); |
655bfd7a | 346 | device_unregister(&bd->dev); |
1da177e4 LT |
347 | } |
348 | EXPORT_SYMBOL(backlight_device_unregister); | |
349 | ||
350 | static void __exit backlight_class_exit(void) | |
351 | { | |
655bfd7a | 352 | class_destroy(backlight_class); |
1da177e4 LT |
353 | } |
354 | ||
355 | static int __init backlight_class_init(void) | |
356 | { | |
655bfd7a RP |
357 | backlight_class = class_create(THIS_MODULE, "backlight"); |
358 | if (IS_ERR(backlight_class)) { | |
359 | printk(KERN_WARNING "Unable to create backlight class; errno = %ld\n", | |
360 | PTR_ERR(backlight_class)); | |
361 | return PTR_ERR(backlight_class); | |
362 | } | |
363 | ||
364 | backlight_class->dev_attrs = bl_device_attributes; | |
c835ee7f RP |
365 | backlight_class->suspend = backlight_suspend; |
366 | backlight_class->resume = backlight_resume; | |
655bfd7a | 367 | return 0; |
1da177e4 LT |
368 | } |
369 | ||
370 | /* | |
371 | * if this is compiled into the kernel, we need to ensure that the | |
372 | * class is registered before users of the class try to register lcd's | |
373 | */ | |
374 | postcore_initcall(backlight_class_init); | |
375 | module_exit(backlight_class_exit); | |
376 | ||
377 | MODULE_LICENSE("GPL"); | |
378 | MODULE_AUTHOR("Jamey Hicks <jamey.hicks@hp.com>, Andrew Zabolotny <zap@homelink.ru>"); | |
379 | MODULE_DESCRIPTION("Backlight Lowlevel Control Abstraction"); |