Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * LCD 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/lcd.h> | |
12 | #include <linux/notifier.h> | |
13 | #include <linux/ctype.h> | |
14 | #include <linux/err.h> | |
15 | #include <linux/fb.h> | |
1da177e4 | 16 | |
3d5eeadd JS |
17 | #if defined(CONFIG_FB) || (defined(CONFIG_FB_MODULE) && \ |
18 | defined(CONFIG_LCD_CLASS_DEVICE_MODULE)) | |
19 | /* This callback gets called when something important happens inside a | |
20 | * framebuffer driver. We're looking if that important event is blanking, | |
21 | * and if it is, we're switching lcd power as well ... | |
22 | */ | |
23 | static int fb_notifier_callback(struct notifier_block *self, | |
24 | unsigned long event, void *data) | |
25 | { | |
26 | struct lcd_device *ld; | |
27 | struct fb_event *evdata = data; | |
28 | ||
29 | /* If we aren't interested in this event, skip it immediately ... */ | |
faa312da EM |
30 | switch (event) { |
31 | case FB_EVENT_BLANK: | |
32 | case FB_EVENT_MODE_CHANGE: | |
33 | case FB_EVENT_MODE_CHANGE_ALL: | |
34 | break; | |
35 | default: | |
3d5eeadd | 36 | return 0; |
faa312da | 37 | } |
3d5eeadd JS |
38 | |
39 | ld = container_of(self, struct lcd_device, fb_notif); | |
faa312da EM |
40 | if (!ld->ops) |
41 | return 0; | |
42 | ||
599a52d1 | 43 | mutex_lock(&ld->ops_lock); |
faa312da | 44 | if (!ld->ops->check_fb || ld->ops->check_fb(ld, evdata->info)) { |
b3b4dc88 BD |
45 | if (event == FB_EVENT_BLANK) { |
46 | if (ld->ops->set_power) | |
47 | ld->ops->set_power(ld, *(int *)evdata->data); | |
48 | } else { | |
49 | if (ld->ops->set_mode) | |
50 | ld->ops->set_mode(ld, evdata->data); | |
51 | } | |
faa312da | 52 | } |
599a52d1 | 53 | mutex_unlock(&ld->ops_lock); |
3d5eeadd JS |
54 | return 0; |
55 | } | |
56 | ||
57 | static int lcd_register_fb(struct lcd_device *ld) | |
58 | { | |
1e0fa6bd | 59 | memset(&ld->fb_notif, 0, sizeof(ld->fb_notif)); |
3d5eeadd JS |
60 | ld->fb_notif.notifier_call = fb_notifier_callback; |
61 | return fb_register_client(&ld->fb_notif); | |
62 | } | |
63 | ||
64 | static void lcd_unregister_fb(struct lcd_device *ld) | |
65 | { | |
66 | fb_unregister_client(&ld->fb_notif); | |
67 | } | |
68 | #else | |
69 | static int lcd_register_fb(struct lcd_device *ld) | |
70 | { | |
71 | return 0; | |
72 | } | |
73 | ||
74 | static inline void lcd_unregister_fb(struct lcd_device *ld) | |
75 | { | |
76 | } | |
77 | #endif /* CONFIG_FB */ | |
78 | ||
655bfd7a RP |
79 | static ssize_t lcd_show_power(struct device *dev, struct device_attribute *attr, |
80 | char *buf) | |
1da177e4 LT |
81 | { |
82 | int rc; | |
655bfd7a | 83 | struct lcd_device *ld = to_lcd_device(dev); |
1da177e4 | 84 | |
599a52d1 RP |
85 | mutex_lock(&ld->ops_lock); |
86 | if (ld->ops && ld->ops->get_power) | |
87 | rc = sprintf(buf, "%d\n", ld->ops->get_power(ld)); | |
1da177e4 LT |
88 | else |
89 | rc = -ENXIO; | |
599a52d1 | 90 | mutex_unlock(&ld->ops_lock); |
1da177e4 LT |
91 | |
92 | return rc; | |
93 | } | |
94 | ||
655bfd7a RP |
95 | static ssize_t lcd_store_power(struct device *dev, |
96 | struct device_attribute *attr, const char *buf, size_t count) | |
1da177e4 | 97 | { |
68673afd | 98 | int rc = -ENXIO; |
1da177e4 | 99 | char *endp; |
655bfd7a | 100 | struct lcd_device *ld = to_lcd_device(dev); |
68673afd RP |
101 | int power = simple_strtoul(buf, &endp, 0); |
102 | size_t size = endp - buf; | |
1da177e4 | 103 | |
e7d2860b | 104 | if (isspace(*endp)) |
68673afd RP |
105 | size++; |
106 | if (size != count) | |
1da177e4 LT |
107 | return -EINVAL; |
108 | ||
599a52d1 RP |
109 | mutex_lock(&ld->ops_lock); |
110 | if (ld->ops && ld->ops->set_power) { | |
1da177e4 | 111 | pr_debug("lcd: set power to %d\n", power); |
599a52d1 | 112 | ld->ops->set_power(ld, power); |
1da177e4 | 113 | rc = count; |
68673afd | 114 | } |
599a52d1 | 115 | mutex_unlock(&ld->ops_lock); |
1da177e4 LT |
116 | |
117 | return rc; | |
118 | } | |
119 | ||
655bfd7a RP |
120 | static ssize_t lcd_show_contrast(struct device *dev, |
121 | struct device_attribute *attr, char *buf) | |
1da177e4 | 122 | { |
68673afd | 123 | int rc = -ENXIO; |
655bfd7a | 124 | struct lcd_device *ld = to_lcd_device(dev); |
1da177e4 | 125 | |
599a52d1 RP |
126 | mutex_lock(&ld->ops_lock); |
127 | if (ld->ops && ld->ops->get_contrast) | |
128 | rc = sprintf(buf, "%d\n", ld->ops->get_contrast(ld)); | |
129 | mutex_unlock(&ld->ops_lock); | |
1da177e4 LT |
130 | |
131 | return rc; | |
132 | } | |
133 | ||
655bfd7a RP |
134 | static ssize_t lcd_store_contrast(struct device *dev, |
135 | struct device_attribute *attr, const char *buf, size_t count) | |
1da177e4 | 136 | { |
68673afd | 137 | int rc = -ENXIO; |
1da177e4 | 138 | char *endp; |
655bfd7a | 139 | struct lcd_device *ld = to_lcd_device(dev); |
68673afd RP |
140 | int contrast = simple_strtoul(buf, &endp, 0); |
141 | size_t size = endp - buf; | |
1da177e4 | 142 | |
e7d2860b | 143 | if (isspace(*endp)) |
68673afd RP |
144 | size++; |
145 | if (size != count) | |
1da177e4 LT |
146 | return -EINVAL; |
147 | ||
599a52d1 RP |
148 | mutex_lock(&ld->ops_lock); |
149 | if (ld->ops && ld->ops->set_contrast) { | |
1da177e4 | 150 | pr_debug("lcd: set contrast to %d\n", contrast); |
599a52d1 | 151 | ld->ops->set_contrast(ld, contrast); |
1da177e4 | 152 | rc = count; |
68673afd | 153 | } |
599a52d1 | 154 | mutex_unlock(&ld->ops_lock); |
1da177e4 LT |
155 | |
156 | return rc; | |
157 | } | |
158 | ||
655bfd7a RP |
159 | static ssize_t lcd_show_max_contrast(struct device *dev, |
160 | struct device_attribute *attr, char *buf) | |
1da177e4 | 161 | { |
655bfd7a | 162 | struct lcd_device *ld = to_lcd_device(dev); |
1da177e4 | 163 | |
599a52d1 | 164 | return sprintf(buf, "%d\n", ld->props.max_contrast); |
1da177e4 LT |
165 | } |
166 | ||
0ad90efd | 167 | static struct class *lcd_class; |
655bfd7a RP |
168 | |
169 | static void lcd_device_release(struct device *dev) | |
1da177e4 LT |
170 | { |
171 | struct lcd_device *ld = to_lcd_device(dev); | |
172 | kfree(ld); | |
173 | } | |
174 | ||
655bfd7a RP |
175 | static struct device_attribute lcd_device_attributes[] = { |
176 | __ATTR(lcd_power, 0644, lcd_show_power, lcd_store_power), | |
177 | __ATTR(contrast, 0644, lcd_show_contrast, lcd_store_contrast), | |
178 | __ATTR(max_contrast, 0444, lcd_show_max_contrast, NULL), | |
179 | __ATTR_NULL, | |
1da177e4 LT |
180 | }; |
181 | ||
1da177e4 LT |
182 | /** |
183 | * lcd_device_register - register a new object of lcd_device class. | |
184 | * @name: the name of the new object(must be the same as the name of the | |
185 | * respective framebuffer device). | |
655bfd7a RP |
186 | * @devdata: an optional pointer to be stored in the device. The |
187 | * methods may retrieve it by using lcd_get_data(ld). | |
599a52d1 | 188 | * @ops: the lcd operations structure. |
1da177e4 | 189 | * |
655bfd7a | 190 | * Creates and registers a new lcd device. Returns either an ERR_PTR() |
1da177e4 LT |
191 | * or a pointer to the newly allocated device. |
192 | */ | |
655bfd7a RP |
193 | struct lcd_device *lcd_device_register(const char *name, struct device *parent, |
194 | void *devdata, struct lcd_ops *ops) | |
1da177e4 | 195 | { |
1da177e4 | 196 | struct lcd_device *new_ld; |
655bfd7a | 197 | int rc; |
1da177e4 LT |
198 | |
199 | pr_debug("lcd_device_register: name=%s\n", name); | |
200 | ||
599a52d1 | 201 | new_ld = kzalloc(sizeof(struct lcd_device), GFP_KERNEL); |
90968e8e | 202 | if (!new_ld) |
10ad1b73 | 203 | return ERR_PTR(-ENOMEM); |
1da177e4 | 204 | |
599a52d1 | 205 | mutex_init(&new_ld->ops_lock); |
28ee086d | 206 | mutex_init(&new_ld->update_lock); |
1da177e4 | 207 | |
655bfd7a RP |
208 | new_ld->dev.class = lcd_class; |
209 | new_ld->dev.parent = parent; | |
210 | new_ld->dev.release = lcd_device_release; | |
64dba9a9 | 211 | dev_set_name(&new_ld->dev, name); |
655bfd7a RP |
212 | dev_set_drvdata(&new_ld->dev, devdata); |
213 | ||
214 | rc = device_register(&new_ld->dev); | |
90968e8e | 215 | if (rc) { |
2fd5a154 | 216 | kfree(new_ld); |
1da177e4 LT |
217 | return ERR_PTR(rc); |
218 | } | |
219 | ||
3d5eeadd | 220 | rc = lcd_register_fb(new_ld); |
2fd5a154 | 221 | if (rc) { |
655bfd7a | 222 | device_unregister(&new_ld->dev); |
2fd5a154 DT |
223 | return ERR_PTR(rc); |
224 | } | |
1da177e4 | 225 | |
655bfd7a | 226 | new_ld->ops = ops; |
1da177e4 LT |
227 | |
228 | return new_ld; | |
229 | } | |
230 | EXPORT_SYMBOL(lcd_device_register); | |
231 | ||
232 | /** | |
233 | * lcd_device_unregister - unregisters a object of lcd_device class. | |
234 | * @ld: the lcd device object to be unregistered and freed. | |
235 | * | |
236 | * Unregisters a previously registered via lcd_device_register object. | |
237 | */ | |
238 | void lcd_device_unregister(struct lcd_device *ld) | |
239 | { | |
1da177e4 LT |
240 | if (!ld) |
241 | return; | |
242 | ||
599a52d1 RP |
243 | mutex_lock(&ld->ops_lock); |
244 | ld->ops = NULL; | |
245 | mutex_unlock(&ld->ops_lock); | |
3d5eeadd | 246 | lcd_unregister_fb(ld); |
655bfd7a RP |
247 | |
248 | device_unregister(&ld->dev); | |
1da177e4 LT |
249 | } |
250 | EXPORT_SYMBOL(lcd_device_unregister); | |
251 | ||
252 | static void __exit lcd_class_exit(void) | |
253 | { | |
655bfd7a | 254 | class_destroy(lcd_class); |
1da177e4 LT |
255 | } |
256 | ||
257 | static int __init lcd_class_init(void) | |
258 | { | |
655bfd7a RP |
259 | lcd_class = class_create(THIS_MODULE, "lcd"); |
260 | if (IS_ERR(lcd_class)) { | |
261 | printk(KERN_WARNING "Unable to create backlight class; errno = %ld\n", | |
262 | PTR_ERR(lcd_class)); | |
263 | return PTR_ERR(lcd_class); | |
264 | } | |
265 | ||
266 | lcd_class->dev_attrs = lcd_device_attributes; | |
267 | return 0; | |
1da177e4 LT |
268 | } |
269 | ||
270 | /* | |
271 | * if this is compiled into the kernel, we need to ensure that the | |
272 | * class is registered before users of the class try to register lcd's | |
273 | */ | |
274 | postcore_initcall(lcd_class_init); | |
275 | module_exit(lcd_class_exit); | |
276 | ||
277 | MODULE_LICENSE("GPL"); | |
278 | MODULE_AUTHOR("Jamey Hicks <jamey.hicks@hp.com>, Andrew Zabolotny <zap@homelink.ru>"); | |
279 | MODULE_DESCRIPTION("LCD Lowlevel Control Abstraction"); |