Skip to content

Commit

Permalink
---
Browse files Browse the repository at this point in the history
yaml
---
r: 261370
b: refs/heads/master
c: 78866ef
h: refs/heads/master
v: v3
  • Loading branch information
Hans Verkuil authored and Mauro Carvalho Chehab committed Jul 27, 2011
1 parent 7993d1c commit 72dc223
Show file tree
Hide file tree
Showing 2 changed files with 5 additions and 10 deletions.
2 changes: 1 addition & 1 deletion [refs]
Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: ddac5c107942d9584a9f55701aad405b57618726
refs/heads/master: 78866efe8ae2862fef7ff37af36c6972651c2d0b
13 changes: 4 additions & 9 deletions trunk/Documentation/video4linux/v4l2-controls.txt
Original file line number Diff line number Diff line change
Expand Up @@ -277,16 +277,13 @@ implement g_volatile_ctrl like this:
{
switch (ctrl->id) {
case V4L2_CID_BRIGHTNESS:
ctrl->cur.val = read_reg(0x123);
ctrl->val = read_reg(0x123);
break;
}
}

The 'new value' union is not used in g_volatile_ctrl. In general controls
that need to implement g_volatile_ctrl are read-only controls.

Note that if one or more controls in a control cluster are marked as volatile,
then all the controls in the cluster are seen as volatile.
Note that you use the 'new value' union as well in g_volatile_ctrl. In general
controls that need to implement g_volatile_ctrl are read-only controls.

To mark a control as volatile you have to set the is_volatile flag:

Expand Down Expand Up @@ -636,9 +633,7 @@ button controls are write-only controls.
-EINVAL as the spec says.

5) The spec does not mention what should happen when you try to set/get a
control class controls. ivtv currently returns -EINVAL (indicating that the
control ID does not exist) while the framework will return -EACCES, which
makes more sense.
control class controls. The framework will return -EACCES.


Proposals for Extensions
Expand Down

0 comments on commit 72dc223

Please sign in to comment.