[media] v4l2 core: enable all interface links at init

Interface links are normally enabled, meaning that the interfaces are
bound to the entities. So, any ioctl send to the interface are reflected
at the entities managed by the interface.

However, when a device is used, other interfaces for the same hardware
could be decoupled from the entities linked to them, because the
hardware may have some parts busy.

That's for example, what happens when an hybrid TV device is in use.
If it is streaming analog TV or capturing signals from S-Video/Composite
connectors, typically the digital part of the hardware can't be used and
vice-versa.

This is generally due to some internal hardware or firmware limitation,
that it is not easily mapped via data pipelines.

What the Kernel drivers do internally is that they decouple the hardware
from the interface. So, all changes, if allowed, are done only at some
interface cache, but not physically changed at the hardware.

The usage is similar to the usage of the MEDIA_LNK_FL_ENABLED on data
links. So, let's use the same flag to indicate if either the interface
to entity link is bound/enabled or not.

Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
index 077cdc92778cd054a08f9771223e64d8d1803953..d36436582de96b409be0f6f034c7f3e0dc74b6ea 100644 (file)
--- a/drivers/media/v4l2-core/v4l2-dev.c
+++ b/drivers/media/v4l2-core/v4l2-dev.c
@@ -797,7 +797,8 @@ static int video_register_media_controller(struct video_device *vdev, int type)
                struct media_link *link;
 
                link = media_create_intf_link(&vdev->entity,
-                                             &vdev->intf_devnode->intf, 0);
+                                             &vdev->intf_devnode->intf,
+                                             MEDIA_LNK_FL_ENABLED);
                if (!link) {
                        media_devnode_remove(vdev->intf_devnode);
                        media_device_unregister_entity(&vdev->entity);

diff --git a/drivers/media/v4l2-core/v4l2-device.c b/drivers/media/v4l2-core/v4l2-device.c
index 3c87307e56f08ecffdda2f320416178b4b7ae5b2..85f724b53a148b422a3e4d9e5a37383756019eeb 100644 (file)
--- a/drivers/media/v4l2-core/v4l2-device.c
+++ b/drivers/media/v4l2-core/v4l2-device.c
@@ -265,7 +265,7 @@ int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev)
 
                        link = media_create_intf_link(&sd->entity,
                                                      &vdev->intf_devnode->intf,
-                                                     0);
+                                                     MEDIA_LNK_FL_ENABLED);
                        if (!link)
                                goto clean_up;
                }