From 76df39fa82645bb0c9cd30bf981d54ab2c332d32 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Fri, 1 Sep 2017 13:44:28 -0400 Subject: [PATCH] media: dmx-get-pes-pids.rst: document the ioctl This ioctl is supported by the DVB core, but was never documented. Add a documentation for it. Signed-off-by: Mauro Carvalho Chehab --- .../media/uapi/dvb/dmx-get-pes-pids.rst | 22 +++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) diff --git a/Documentation/media/uapi/dvb/dmx-get-pes-pids.rst b/Documentation/media/uapi/dvb/dmx-get-pes-pids.rst index 20288c11d279..fbdbc12869d1 100644 --- a/Documentation/media/uapi/dvb/dmx-get-pes-pids.rst +++ b/Documentation/media/uapi/dvb/dmx-get-pes-pids.rst @@ -25,13 +25,31 @@ Arguments File descriptor returned by :c:func:`open() `. ``pids`` - Undocumented. + Array used to store 5 Program IDs. Description ----------- -.. note:: This ioctl is undocumented. Documentation is welcome. +This ioctl allows to query a DVB device to return the first PID used +by audio, video, textext, subtitle and PCR programs on a given service. +They're stored as: + +======================= ======== ======================================= +PID element position content +======================= ======== ======================================= +pids[DMX_PES_AUDIO] 0 first audio PID +pids[DMX_PES_VIDEO] 1 first video PID +pids[DMX_PES_TELETEXT] 2 first teletext PID +pids[DMX_PES_SUBTITLE] 3 first subtitle PID +pids[DMX_PES_PCR] 4 first Program Clock Reference PID +======================= ======== ======================================= + + +.. note:: + + A value equal to 0xffff means that the PID was not filled by the + Kernel. Return Value -- 2.20.1