V4L/DVB (8389): videodev: simplify get_index()

Use Hans Verkuil's suggested method of implementing get_index which doesn't
depend on class_for_each_device and instead uses the video_device array. This
simplifies the code and reduces its memory footprint.

Signed-off-by: Brandon Philips <bphilips@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This commit is contained in:
Brandon Philips 2008-06-24 22:58:25 -03:00 committed by Mauro Carvalho Chehab
parent 2bc93aa304
commit 8373a3e512

View File

@ -2011,25 +2011,8 @@ int video_ioctl2 (struct inode *inode, struct file *file,
}
EXPORT_SYMBOL(video_ioctl2);
struct index_info {
struct device *dev;
unsigned int used[VIDEO_NUM_DEVICES];
};
static int __fill_index_info(struct device *cd, void *data)
{
struct index_info *info = data;
struct video_device *vfd = container_of(cd, struct video_device,
class_dev);
if (info->dev == vfd->dev)
info->used[vfd->index] = 1;
return 0;
}
/**
* assign_index - assign stream number based on parent device
* get_index - assign stream number based on parent device
* @vdev: video_device to assign index number to, vdev->dev should be assigned
* @num: -1 if auto assign, requested number otherwise
*
@ -2039,44 +2022,30 @@ static int __fill_index_info(struct device *cd, void *data)
*/
static int get_index(struct video_device *vdev, int num)
{
struct index_info *info;
u32 used = 0;
int i;
int ret = 0;
if (num >= VIDEO_NUM_DEVICES)
if (num >= 32) {
printk(KERN_ERR "videodev: %s num is too large\n", __func__);
return -EINVAL;
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info)
return -ENOMEM;
info->dev = vdev->dev;
ret = class_for_each_device(&video_class, info,
__fill_index_info);
if (ret < 0)
goto out;
if (num >= 0) {
if (!info->used[num])
ret = num;
else
ret = -ENFILE;
goto out;
}
for (i = 0; i < VIDEO_NUM_DEVICES; i++) {
if (info->used[i])
continue;
ret = i;
goto out;
if (video_device[i] != NULL &&
video_device[i] != vdev &&
video_device[i]->dev == vdev->dev) {
used |= 1 << video_device[i]->index;
}
}
out:
kfree(info);
return ret;
if (num >= 0) {
if (used & (1 << num))
return -ENFILE;
return num;
}
i = ffz(used);
return i >= 32 ? -ENFILE : i;
}
static const struct file_operations video_fops;