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 <g.liakhovet...@gmx.de>
---
v4:
1. added "static" in v4l2_device_release_subdev_node() definition
2. removed superfluous get_device() and put_device() (thanks to Laurent
for pointing out)
drivers/media/video/v4l2-device.c | 36 +++++++++++++++++++++++++++++++-----
include/media/v4l2-subdev.h | 4 ++--
2 files changed, 33 insertions(+), 7 deletions(-)
diff --git a/drivers/media/video/v4l2-device.c
b/drivers/media/video/v4l2-device.c
index c72856c..8abf830 100644
--- a/drivers/media/video/v4l2-device.c
+++ b/drivers/media/video/v4l2-device.c
@@ -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
@@ -191,6 +192,13 @@ 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;
@@ -204,22 +212,40 @@ 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);
@@ -245,7 +271,7 @@ 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);
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index 257da1a..5dd049a 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -534,13 +534,13 @@ struct v4l2_subdev {
void *dev_priv;
void *host_priv;
/* subdev device node */
- struct video_device devnode;
+ struct video_device *devnode;
};
#define media_entity_to_v4l2_subdev(ent) \
container_of(ent, struct v4l2_subdev, entity)
#define vdev_to_v4l2_subdev(vdev) \
- container_of(vdev, struct v4l2_subdev, devnode)
+ video_get_drvdata(vdev)
/*
* Used for storing subdev information per file handle
--
1.7.2.5
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
