diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/video/backlight/backlight.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/video/backlight/backlight.c')
-rw-r--r-- | drivers/video/backlight/backlight.c | 264 |
1 files changed, 264 insertions, 0 deletions
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c new file mode 100644 index 000000000000..acc81cb01d56 --- /dev/null +++ b/drivers/video/backlight/backlight.c | |||
@@ -0,0 +1,264 @@ | |||
1 | /* | ||
2 | * Backlight Lowlevel Control Abstraction | ||
3 | * | ||
4 | * Copyright (C) 2003,2004 Hewlett-Packard Company | ||
5 | * | ||
6 | */ | ||
7 | |||
8 | #include <linux/version.h> | ||
9 | #include <linux/module.h> | ||
10 | #include <linux/init.h> | ||
11 | #include <linux/device.h> | ||
12 | #include <linux/backlight.h> | ||
13 | #include <linux/notifier.h> | ||
14 | #include <linux/ctype.h> | ||
15 | #include <linux/err.h> | ||
16 | #include <linux/fb.h> | ||
17 | #include <asm/bug.h> | ||
18 | |||
19 | static ssize_t backlight_show_power(struct class_device *cdev, char *buf) | ||
20 | { | ||
21 | int rc; | ||
22 | struct backlight_device *bd = to_backlight_device(cdev); | ||
23 | |||
24 | down(&bd->sem); | ||
25 | if (likely(bd->props && bd->props->get_power)) | ||
26 | rc = sprintf(buf, "%d\n", bd->props->get_power(bd)); | ||
27 | else | ||
28 | rc = -ENXIO; | ||
29 | up(&bd->sem); | ||
30 | |||
31 | return rc; | ||
32 | } | ||
33 | |||
34 | static ssize_t backlight_store_power(struct class_device *cdev, const char *buf, size_t count) | ||
35 | { | ||
36 | int rc, power; | ||
37 | char *endp; | ||
38 | struct backlight_device *bd = to_backlight_device(cdev); | ||
39 | |||
40 | power = simple_strtoul(buf, &endp, 0); | ||
41 | if (*endp && !isspace(*endp)) | ||
42 | return -EINVAL; | ||
43 | |||
44 | down(&bd->sem); | ||
45 | if (likely(bd->props && bd->props->set_power)) { | ||
46 | pr_debug("backlight: set power to %d\n", power); | ||
47 | bd->props->set_power(bd, power); | ||
48 | rc = count; | ||
49 | } else | ||
50 | rc = -ENXIO; | ||
51 | up(&bd->sem); | ||
52 | |||
53 | return rc; | ||
54 | } | ||
55 | |||
56 | static ssize_t backlight_show_brightness(struct class_device *cdev, char *buf) | ||
57 | { | ||
58 | int rc; | ||
59 | struct backlight_device *bd = to_backlight_device(cdev); | ||
60 | |||
61 | down(&bd->sem); | ||
62 | if (likely(bd->props && bd->props->get_brightness)) | ||
63 | rc = sprintf(buf, "%d\n", bd->props->get_brightness(bd)); | ||
64 | else | ||
65 | rc = -ENXIO; | ||
66 | up(&bd->sem); | ||
67 | |||
68 | return rc; | ||
69 | } | ||
70 | |||
71 | static ssize_t backlight_store_brightness(struct class_device *cdev, const char *buf, size_t count) | ||
72 | { | ||
73 | int rc, brightness; | ||
74 | char *endp; | ||
75 | struct backlight_device *bd = to_backlight_device(cdev); | ||
76 | |||
77 | brightness = simple_strtoul(buf, &endp, 0); | ||
78 | if (*endp && !isspace(*endp)) | ||
79 | return -EINVAL; | ||
80 | |||
81 | down(&bd->sem); | ||
82 | if (likely(bd->props && bd->props->set_brightness)) { | ||
83 | pr_debug("backlight: set brightness to %d\n", brightness); | ||
84 | bd->props->set_brightness(bd, brightness); | ||
85 | rc = count; | ||
86 | } else | ||
87 | rc = -ENXIO; | ||
88 | up(&bd->sem); | ||
89 | |||
90 | return rc; | ||
91 | } | ||
92 | |||
93 | static ssize_t backlight_show_max_brightness(struct class_device *cdev, char *buf) | ||
94 | { | ||
95 | int rc; | ||
96 | struct backlight_device *bd = to_backlight_device(cdev); | ||
97 | |||
98 | down(&bd->sem); | ||
99 | if (likely(bd->props)) | ||
100 | rc = sprintf(buf, "%d\n", bd->props->max_brightness); | ||
101 | else | ||
102 | rc = -ENXIO; | ||
103 | up(&bd->sem); | ||
104 | |||
105 | return rc; | ||
106 | } | ||
107 | |||
108 | static void backlight_class_release(struct class_device *dev) | ||
109 | { | ||
110 | struct backlight_device *bd = to_backlight_device(dev); | ||
111 | kfree(bd); | ||
112 | } | ||
113 | |||
114 | static struct class backlight_class = { | ||
115 | .name = "backlight", | ||
116 | .release = backlight_class_release, | ||
117 | }; | ||
118 | |||
119 | #define DECLARE_ATTR(_name,_mode,_show,_store) \ | ||
120 | { \ | ||
121 | .attr = { .name = __stringify(_name), .mode = _mode, .owner = THIS_MODULE }, \ | ||
122 | .show = _show, \ | ||
123 | .store = _store, \ | ||
124 | } | ||
125 | |||
126 | static struct class_device_attribute bl_class_device_attributes[] = { | ||
127 | DECLARE_ATTR(power, 0644, backlight_show_power, backlight_store_power), | ||
128 | DECLARE_ATTR(brightness, 0644, backlight_show_brightness, backlight_store_brightness), | ||
129 | DECLARE_ATTR(max_brightness, 0444, backlight_show_max_brightness, NULL), | ||
130 | }; | ||
131 | |||
132 | /* This callback gets called when something important happens inside a | ||
133 | * framebuffer driver. We're looking if that important event is blanking, | ||
134 | * and if it is, we're switching backlight power as well ... | ||
135 | */ | ||
136 | static int fb_notifier_callback(struct notifier_block *self, | ||
137 | unsigned long event, void *data) | ||
138 | { | ||
139 | struct backlight_device *bd; | ||
140 | struct fb_event *evdata =(struct fb_event *)data; | ||
141 | |||
142 | /* If we aren't interested in this event, skip it immediately ... */ | ||
143 | if (event != FB_EVENT_BLANK) | ||
144 | return 0; | ||
145 | |||
146 | bd = container_of(self, struct backlight_device, fb_notif); | ||
147 | down(&bd->sem); | ||
148 | if (bd->props) | ||
149 | if (!bd->props->check_fb || bd->props->check_fb(evdata->info)) | ||
150 | bd->props->set_power(bd, *(int *)evdata->data); | ||
151 | up(&bd->sem); | ||
152 | return 0; | ||
153 | } | ||
154 | |||
155 | /** | ||
156 | * backlight_device_register - create and register a new object of | ||
157 | * backlight_device class. | ||
158 | * @name: the name of the new object(must be the same as the name of the | ||
159 | * respective framebuffer device). | ||
160 | * @devdata: an optional pointer to be stored in the class_device. The | ||
161 | * methods may retrieve it by using class_get_devdata(&bd->class_dev). | ||
162 | * @bp: the backlight properties structure. | ||
163 | * | ||
164 | * Creates and registers new backlight class_device. Returns either an | ||
165 | * ERR_PTR() or a pointer to the newly allocated device. | ||
166 | */ | ||
167 | struct backlight_device *backlight_device_register(const char *name, void *devdata, | ||
168 | struct backlight_properties *bp) | ||
169 | { | ||
170 | int i, rc; | ||
171 | struct backlight_device *new_bd; | ||
172 | |||
173 | pr_debug("backlight_device_alloc: name=%s\n", name); | ||
174 | |||
175 | new_bd = kmalloc(sizeof(struct backlight_device), GFP_KERNEL); | ||
176 | if (unlikely(!new_bd)) | ||
177 | return ERR_PTR(ENOMEM); | ||
178 | |||
179 | init_MUTEX(&new_bd->sem); | ||
180 | new_bd->props = bp; | ||
181 | memset(&new_bd->class_dev, 0, sizeof(new_bd->class_dev)); | ||
182 | new_bd->class_dev.class = &backlight_class; | ||
183 | strlcpy(new_bd->class_dev.class_id, name, KOBJ_NAME_LEN); | ||
184 | class_set_devdata(&new_bd->class_dev, devdata); | ||
185 | |||
186 | rc = class_device_register(&new_bd->class_dev); | ||
187 | if (unlikely(rc)) { | ||
188 | error: kfree(new_bd); | ||
189 | return ERR_PTR(rc); | ||
190 | } | ||
191 | |||
192 | memset(&new_bd->fb_notif, 0, sizeof(new_bd->fb_notif)); | ||
193 | new_bd->fb_notif.notifier_call = fb_notifier_callback; | ||
194 | |||
195 | rc = fb_register_client(&new_bd->fb_notif); | ||
196 | if (unlikely(rc)) | ||
197 | goto error; | ||
198 | |||
199 | for (i = 0; i < ARRAY_SIZE(bl_class_device_attributes); i++) { | ||
200 | rc = class_device_create_file(&new_bd->class_dev, | ||
201 | &bl_class_device_attributes[i]); | ||
202 | if (unlikely(rc)) { | ||
203 | while (--i >= 0) | ||
204 | class_device_remove_file(&new_bd->class_dev, | ||
205 | &bl_class_device_attributes[i]); | ||
206 | class_device_unregister(&new_bd->class_dev); | ||
207 | /* No need to kfree(new_bd) since release() method was called */ | ||
208 | return ERR_PTR(rc); | ||
209 | } | ||
210 | } | ||
211 | |||
212 | return new_bd; | ||
213 | } | ||
214 | EXPORT_SYMBOL(backlight_device_register); | ||
215 | |||
216 | /** | ||
217 | * backlight_device_unregister - unregisters a backlight device object. | ||
218 | * @bd: the backlight device object to be unregistered and freed. | ||
219 | * | ||
220 | * Unregisters a previously registered via backlight_device_register object. | ||
221 | */ | ||
222 | void backlight_device_unregister(struct backlight_device *bd) | ||
223 | { | ||
224 | int i; | ||
225 | |||
226 | if (!bd) | ||
227 | return; | ||
228 | |||
229 | pr_debug("backlight_device_unregister: name=%s\n", bd->class_dev.class_id); | ||
230 | |||
231 | for (i = 0; i < ARRAY_SIZE(bl_class_device_attributes); i++) | ||
232 | class_device_remove_file(&bd->class_dev, | ||
233 | &bl_class_device_attributes[i]); | ||
234 | |||
235 | down(&bd->sem); | ||
236 | bd->props = NULL; | ||
237 | up(&bd->sem); | ||
238 | |||
239 | fb_unregister_client(&bd->fb_notif); | ||
240 | |||
241 | class_device_unregister(&bd->class_dev); | ||
242 | } | ||
243 | EXPORT_SYMBOL(backlight_device_unregister); | ||
244 | |||
245 | static void __exit backlight_class_exit(void) | ||
246 | { | ||
247 | class_unregister(&backlight_class); | ||
248 | } | ||
249 | |||
250 | static int __init backlight_class_init(void) | ||
251 | { | ||
252 | return class_register(&backlight_class); | ||
253 | } | ||
254 | |||
255 | /* | ||
256 | * if this is compiled into the kernel, we need to ensure that the | ||
257 | * class is registered before users of the class try to register lcd's | ||
258 | */ | ||
259 | postcore_initcall(backlight_class_init); | ||
260 | module_exit(backlight_class_exit); | ||
261 | |||
262 | MODULE_LICENSE("GPL"); | ||
263 | MODULE_AUTHOR("Jamey Hicks <jamey.hicks@hp.com>, Andrew Zabolotny <zap@homelink.ru>"); | ||
264 | MODULE_DESCRIPTION("Backlight Lowlevel Control Abstraction"); | ||