[media] V4L: dynamically allocate video_device nodes in subdevices

Currently only very few drivers actually use video_device nodes, embedded
in struct v4l2_subdev. Allocate these nodes dynamically for those drivers
to save memory for the rest.

Signed-off-by: Guennadi Liakhovetski <[email protected]>
Tested-by: Sylwester Nawrocki <[email protected]>
Acked-by: Laurent Pinchart <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>
This commit is contained in:
Guennadi Liakhovetski 2011-09-13 08:07:55 -03:00 • committed by Mauro Carvalho Chehab
commit 3e0ec41c5c
2 changed files with 33 additions and 7 deletions

View file

@ -21,6 +21,7 @@
#include <linux/types.h>
#include <linux/ioctl.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#if defined(CONFIG_SPI)
#include <linux/spi/spi.h>
#endif
@ -193,6 +194,13 @@ int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
}
EXPORT_SYMBOL_GPL(v4l2_device_register_subdev);
static void v4l2_device_release_subdev_node(struct video_device *vdev)
{
struct v4l2_subdev *sd = video_get_drvdata(vdev);
sd->devnode = NULL;
kfree(vdev);
}
int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev)
{
struct video_device *vdev;
@ -206,22 +214,40 @@ int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev)
if (!(sd->flags & V4L2_SUBDEV_FL_HAS_DEVNODE))
continue;
vdev = &sd->devnode;
vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
if (!vdev) {
err = -ENOMEM;
goto clean_up;
}
video_set_drvdata(vdev, sd);
strlcpy(vdev->name, sd->name, sizeof(vdev->name));
vdev->v4l2_dev = v4l2_dev;
vdev->fops = &v4l2_subdev_fops;
vdev->release = video_device_release_empty;
vdev->release = v4l2_device_release_subdev_node;
vdev->ctrl_handler = sd->ctrl_handler;
err = __video_register_device(vdev, VFL_TYPE_SUBDEV, -1, 1,
sd->owner);
if (err < 0)
return err;
if (err < 0) {
kfree(vdev);
goto clean_up;
}
#if defined(CONFIG_MEDIA_CONTROLLER)
sd->entity.v4l.major = VIDEO_MAJOR;
sd->entity.v4l.minor = vdev->minor;
#endif
sd->devnode = vdev;
}
return 0;
clean_up:
list_for_each_entry(sd, &v4l2_dev->subdevs, list) {
if (!sd->devnode)
break;
video_unregister_device(sd->devnode);
}
return err;
}
EXPORT_SYMBOL_GPL(v4l2_device_register_subdev_nodes);
@ -247,7 +273,7 @@ void v4l2_device_unregister_subdev(struct v4l2_subdev *sd)
if (v4l2_dev->mdev)
media_device_unregister_entity(&sd->entity);
#endif
video_unregister_device(&sd->devnode);
video_unregister_device(sd->devnode);
module_put(sd->owner);
}
EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);