tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * output.c - Display Output Switch driver
3 *
4 * Copyright (C) 2006 Luming Yu <luming.yu@intel.com>
5 *
6 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or (at
11 * your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
21 *
22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23 */
24#include <linux/module.h>
25#include <linux/video_output.h>
26#include <linux/err.h>
27#include <linux/ctype.h>
28
29
30MODULE_DESCRIPTION("Display Output Switcher Lowlevel Control Abstraction");
31MODULE_LICENSE("GPL");
32MODULE_AUTHOR("Luming Yu <luming.yu@intel.com>");
33
34static ssize_t video_output_show_state(struct device *dev,
35 struct device_attribute *attr, char *buf)
36{
37 ssize_t ret_size = 0;
38 struct output_device *od = to_output_device(dev);
39 if (od->props)
40 ret_size = sprintf(buf,"%.8x\n",od->props->get_status(od));
41 return ret_size;
42}
43
44static ssize_t video_output_store_state(struct device *dev,
45 struct device_attribute *attr,
46 const char *buf,size_t count)
47{
48 char *endp;
49 struct output_device *od = to_output_device(dev);
50 int request_state = simple_strtoul(buf,&endp,0);
51 size_t size = endp - buf;
52
53 if (*endp && isspace(*endp))
54 size++;
55 if (size != count)
56 return -EINVAL;
57
58 if (od->props) {
59 od->request_state = request_state;
60 od->props->set_state(od);
61 }
62 return count;
63}
64
65static void video_output_release(struct device *dev)
66{
67 struct output_device *od = to_output_device(dev);
68 kfree(od);
69}
70
71static struct device_attribute video_output_attributes[] = {
72 __ATTR(state, 0644, video_output_show_state, video_output_store_state),
73 __ATTR_NULL,
74};
75
76
77static struct class video_output_class = {
78 .name = "video_output",
79 .dev_release = video_output_release,
80 .dev_attrs = video_output_attributes,
81};
82
83struct output_device *video_output_register(const char *name,
84 struct device *dev,
85 void *devdata,
86 struct output_properties *op)
87{
88 struct output_device *new_dev;
89 int ret_code = 0;
90
91 new_dev = kzalloc(sizeof(struct output_device),GFP_KERNEL);
92 if (!new_dev) {
93 ret_code = -ENOMEM;
94 goto error_return;
95 }
96 new_dev->props = op;
97 new_dev->dev.class = &video_output_class;
98 new_dev->dev.parent = dev;
99 strlcpy(new_dev->dev.bus_id,name, BUS_ID_SIZE);
100 dev_set_drvdata(&new_dev->dev, devdata);
101 ret_code = device_register(&new_dev->dev);
102 if (ret_code) {
103 kfree(new_dev);
104 goto error_return;
105 }
106 return new_dev;
107
108error_return:
109 return ERR_PTR(ret_code);
110}
111EXPORT_SYMBOL(video_output_register);
112
113void video_output_unregister(struct output_device *dev)
114{
115 if (!dev)
116 return;
117 device_unregister(&dev->dev);
118}
119EXPORT_SYMBOL(video_output_unregister);
120
121static void __exit video_output_class_exit(void)
122{
123 class_unregister(&video_output_class);
124}
125
126static int __init video_output_class_init(void)
127{
128 return class_register(&video_output_class);
129}
130
131postcore_initcall(video_output_class_init);
132module_exit(video_output_class_exit);