From 8e080c2e6cadada82a6b520e0c23a1cb974822d5 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Sun, 13 Sep 2009 22:16:04 -0300 Subject: V4L/DVB (12761): DocBook: add media API specs The V4L and DVB API's are there for a long time. however, up to now, no efforts were done to merge them to kernel DocBook. This patch adds the current versions of the specs as an unique compendium. Signed-off-by: Mauro Carvalho Chehab --- Documentation/DocBook/v4l/vidioc-g-audioout.xml | 154 ++++++++++++++++++++++++ 1 file changed, 154 insertions(+) create mode 100644 Documentation/DocBook/v4l/vidioc-g-audioout.xml (limited to 'Documentation/DocBook/v4l/vidioc-g-audioout.xml') diff --git a/Documentation/DocBook/v4l/vidioc-g-audioout.xml b/Documentation/DocBook/v4l/vidioc-g-audioout.xml new file mode 100644 index 00000000000..3632730c5c6 --- /dev/null +++ b/Documentation/DocBook/v4l/vidioc-g-audioout.xml @@ -0,0 +1,154 @@ + + + ioctl VIDIOC_G_AUDOUT, VIDIOC_S_AUDOUT + &manvol; + + + + VIDIOC_G_AUDOUT + VIDIOC_S_AUDOUT + Query or select the current audio output + + + + + + int ioctl + int fd + int request + struct v4l2_audioout *argp + + + + + int ioctl + int fd + int request + const struct v4l2_audioout *argp + + + + + + Arguments + + + + fd + + &fd; + + + + request + + VIDIOC_G_AUDOUT, VIDIOC_S_AUDOUT + + + + argp + + + + + + + + + Description + + To query the current audio output applications zero out the +reserved array of a &v4l2-audioout; and +call the VIDIOC_G_AUDOUT ioctl with a pointer +to this structure. Drivers fill the rest of the structure or return an +&EINVAL; when the device has no audio inputs, or none which combine +with the current video output. + + Audio outputs have no writable properties. Nevertheless, to +select the current audio output applications can initialize the +index field and +reserved array (which in the future may +contain writable properties) of a +v4l2_audioout structure and call the +VIDIOC_S_AUDOUT ioctl. Drivers switch to the +requested output or return the &EINVAL; when the index is out of +bounds. This is a write-only ioctl, it does not return the current +audio output attributes as VIDIOC_G_AUDOUT +does. + + Note connectors on a TV card to loop back the received audio +signal to a sound card are not audio outputs in this sense. + + + struct <structname>v4l2_audioout</structname> + + &cs-str; + + + __u32 + index + Identifies the audio output, set by the +driver or application. + + + __u8 + name[32] + Name of the audio output, a NUL-terminated ASCII +string, for example: "Line Out". This information is intended for the +user, preferably the connector label on the device itself. + + + __u32 + capability + Audio capability flags, none defined yet. Drivers +must set this field to zero. + + + __u32 + mode + Audio mode, none defined yet. Drivers and +applications (on VIDIOC_S_AUDOUT) must set this +field to zero. + + + __u32 + reserved[2] + Reserved for future extensions. Drivers and +applications must set the array to zero. + + + +
+ + + + &return-value; + + + + EINVAL + + No audio outputs combine with the current video +output, or the number of the selected audio output is out of bounds or +it does not combine, or there are no audio outputs at all and the +ioctl is not supported. + + + + EBUSY + + I/O is in progress, the output cannot be +switched. + + + + + + + -- cgit v1.2.3-70-g09d2