linux/drivers/video/output.c

134 lines
3.4 KiB
C

/*
* output.c - Display Output Switch driver
*
* Copyright (C) 2006 Luming Yu <luming.yu@intel.com>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#include <linux/module.h>
#include <linux/video_output.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/ctype.h>
MODULE_DESCRIPTION("Display Output Switcher Lowlevel Control Abstraction");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Luming Yu <luming.yu@intel.com>");
static ssize_t state_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
ssize_t ret_size = 0;
struct output_device *od = to_output_device(dev);
if (od->props)
ret_size = sprintf(buf,"%.8x\n",od->props->get_status(od));
return ret_size;
}
static ssize_t state_store(struct device *dev, struct device_attribute *attr,
const char *buf,size_t count)
{
char *endp;
struct output_device *od = to_output_device(dev);
int request_state = simple_strtoul(buf,&endp,0);
size_t size = endp - buf;
if (isspace(*endp))
size++;
if (size != count)
return -EINVAL;
if (od->props) {
od->request_state = request_state;
od->props->set_state(od);
}
return count;
}
static DEVICE_ATTR_RW(state);
static void video_output_release(struct device *dev)
{
struct output_device *od = to_output_device(dev);
kfree(od);
}
static struct attribute *video_output_attrs[] = {
&dev_attr_state.attr,
NULL,
};
ATTRIBUTE_GROUPS(video_output);
static struct class video_output_class = {
.name = "video_output",
.dev_release = video_output_release,
.dev_groups = video_output_groups,
};
struct output_device *video_output_register(const char *name,
struct device *dev,
void *devdata,
struct output_properties *op)
{
struct output_device *new_dev;
int ret_code = 0;
new_dev = kzalloc(sizeof(struct output_device),GFP_KERNEL);
if (!new_dev) {
ret_code = -ENOMEM;
goto error_return;
}
new_dev->props = op;
new_dev->dev.class = &video_output_class;
new_dev->dev.parent = dev;
dev_set_name(&new_dev->dev, "%s", name);
dev_set_drvdata(&new_dev->dev, devdata);
ret_code = device_register(&new_dev->dev);
if (ret_code) {
kfree(new_dev);
goto error_return;
}
return new_dev;
error_return:
return ERR_PTR(ret_code);
}
EXPORT_SYMBOL(video_output_register);
void video_output_unregister(struct output_device *dev)
{
if (!dev)
return;
device_unregister(&dev->dev);
}
EXPORT_SYMBOL(video_output_unregister);
static void __exit video_output_class_exit(void)
{
class_unregister(&video_output_class);
}
static int __init video_output_class_init(void)
{
return class_register(&video_output_class);
}
postcore_initcall(video_output_class_init);
module_exit(video_output_class_exit);