From d0b2f91bede3bd5e3d24dd6803e56eee959c1797 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Thu, 20 Oct 2016 00:10:27 -0300 Subject: Linux-libre 4.8.2-gnu --- Documentation/media/uapi/v4l/vidioc-log-status.rst | 46 ++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 Documentation/media/uapi/v4l/vidioc-log-status.rst (limited to 'Documentation/media/uapi/v4l/vidioc-log-status.rst') diff --git a/Documentation/media/uapi/v4l/vidioc-log-status.rst b/Documentation/media/uapi/v4l/vidioc-log-status.rst new file mode 100644 index 000000000..66fc352c0 --- /dev/null +++ b/Documentation/media/uapi/v4l/vidioc-log-status.rst @@ -0,0 +1,46 @@ +.. -*- coding: utf-8; mode: rst -*- + +.. _VIDIOC_LOG_STATUS: + +*********************** +ioctl VIDIOC_LOG_STATUS +*********************** + +Name +==== + +VIDIOC_LOG_STATUS - Log driver status information + + +Synopsis +======== + +.. cpp:function:: int ioctl( int fd, int request ) + + +Arguments +========= + + + +Description +=========== + +As the video/audio devices become more complicated it becomes harder to +debug problems. When this ioctl is called the driver will output the +current device status to the kernel log. This is particular useful when +dealing with problems like no sound, no video and incorrectly tuned +channels. Also many modern devices autodetect video and audio standards +and this ioctl will report what the device thinks what the standard is. +Mismatches may give an indication where the problem is. + +This ioctl is optional and not all drivers support it. It was introduced +in Linux 2.6.15. + + +Return Value +============ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes ` chapter. -- cgit v1.2.3-54-g00ecf