diff options
Diffstat (limited to 'Documentation/video4linux')
-rw-r--r-- | Documentation/video4linux/v4l2-framework.txt | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 7d09114af00b..3b15608ee070 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt | |||
@@ -577,6 +577,10 @@ You should also set these fields: | |||
577 | (cx8802). Since the v4l2_device cannot be associated with a particular | 577 | (cx8802). Since the v4l2_device cannot be associated with a particular |
578 | PCI device it is setup without a parent device. But when the struct | 578 | PCI device it is setup without a parent device. But when the struct |
579 | video_device is setup you do know which parent PCI device to use. | 579 | video_device is setup you do know which parent PCI device to use. |
580 | - flags: optional. Set to V4L2_FL_USE_FH_PRIO if you want to let the framework | ||
581 | handle the VIDIOC_G/S_PRIORITY ioctls. This requires that you use struct | ||
582 | v4l2_fh. Eventually this flag will disappear once all drivers use the core | ||
583 | priority handling. But for now it has to be set explicitly. | ||
580 | 584 | ||
581 | If you use v4l2_ioctl_ops, then you should set .unlocked_ioctl to video_ioctl2 | 585 | If you use v4l2_ioctl_ops, then you should set .unlocked_ioctl to video_ioctl2 |
582 | in your v4l2_file_operations struct. | 586 | in your v4l2_file_operations struct. |
@@ -775,7 +779,8 @@ struct v4l2_fh | |||
775 | 779 | ||
776 | struct v4l2_fh provides a way to easily keep file handle specific data | 780 | struct v4l2_fh provides a way to easily keep file handle specific data |
777 | that is used by the V4L2 framework. New drivers must use struct v4l2_fh | 781 | that is used by the V4L2 framework. New drivers must use struct v4l2_fh |
778 | since it is also used to implement priority handling (VIDIOC_G/S_PRIORITY). | 782 | since it is also used to implement priority handling (VIDIOC_G/S_PRIORITY) |
783 | if the video_device flag V4L2_FL_USE_FH_PRIO is also set. | ||
779 | 784 | ||
780 | The users of v4l2_fh (in the V4L2 framework, not the driver) know | 785 | The users of v4l2_fh (in the V4L2 framework, not the driver) know |
781 | whether a driver uses v4l2_fh as its file->private_data pointer by | 786 | whether a driver uses v4l2_fh as its file->private_data pointer by |