diff --git a/Documentation/DocBook/media/v4l/compat.xml b/Documentation/DocBook/media/v4l/compat.xml index ce1004a7da52..91410b6e7e08 100644 --- a/Documentation/DocBook/media/v4l/compat.xml +++ b/Documentation/DocBook/media/v4l/compat.xml @@ -2370,6 +2370,14 @@ that used it. It was originally scheduled for removal in 2.6.35. +
+ V4L2 in Linux 3.2 + + + V4L2_CTRL_FLAG_VOLATILE was added to signal volatile controls to userspace. + + +
Relation of V4L2 to other Linux multimedia APIs diff --git a/Documentation/DocBook/media/v4l/v4l2.xml b/Documentation/DocBook/media/v4l/v4l2.xml index 0d05e8747c12..40132c277647 100644 --- a/Documentation/DocBook/media/v4l/v4l2.xml +++ b/Documentation/DocBook/media/v4l/v4l2.xml @@ -127,6 +127,13 @@ structs, ioctls) must be noted in more detail in the history chapter (compat.xml), along with the possible impact on existing drivers and applications. --> + + 3.2 + 2011-08-26 + hv + Added V4L2_CTRL_FLAG_VOLATILE. + + 3.1 2011-06-27 @@ -410,7 +417,7 @@ and discussions on the V4L mailing list. Video for Linux Two API Specification - Revision 3.1 + Revision 3.2 &sub-common; diff --git a/Documentation/DocBook/media/v4l/vidioc-queryctrl.xml b/Documentation/DocBook/media/v4l/vidioc-queryctrl.xml index 677ea646c29f..0ac0057a51c4 100644 --- a/Documentation/DocBook/media/v4l/vidioc-queryctrl.xml +++ b/Documentation/DocBook/media/v4l/vidioc-queryctrl.xml @@ -406,6 +406,15 @@ flag is typically present for relative controls or action controls where writing a value will cause the device to carry out a given action (⪚ motor control) but no meaningful value can be returned. + + V4L2_CTRL_FLAG_VOLATILE + 0x0080 + This control is volatile, which means that the value of the control +changes continuously. A typical example would be the current gain value if the device +is in auto-gain mode. In such a case the hardware calculates the gain value based on +the lighting conditions which can change over time. Note that setting a new value for +a volatile control will have no effect. The new value will just be ignored. + diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h index a5359c6e7577..9d14523487d1 100644 --- a/include/linux/videodev2.h +++ b/include/linux/videodev2.h @@ -1082,6 +1082,7 @@ struct v4l2_querymenu { #define V4L2_CTRL_FLAG_INACTIVE 0x0010 #define V4L2_CTRL_FLAG_SLIDER 0x0020 #define V4L2_CTRL_FLAG_WRITE_ONLY 0x0040 +#define V4L2_CTRL_FLAG_VOLATILE 0x0080 /* Query flag, to be ORed with the control ID */ #define V4L2_CTRL_FLAG_NEXT_CTRL 0x80000000