summaryrefslogtreecommitdiffstats
path: root/Documentation/userspace-api/media/v4l/vidioc-enumaudio.rst
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/userspace-api/media/v4l/vidioc-enumaudio.rst')
-rw-r--r--Documentation/userspace-api/media/v4l/vidioc-enumaudio.rst53
1 files changed, 53 insertions, 0 deletions
diff --git a/Documentation/userspace-api/media/v4l/vidioc-enumaudio.rst b/Documentation/userspace-api/media/v4l/vidioc-enumaudio.rst
new file mode 100644
index 0000000000..7873e5434d
--- /dev/null
+++ b/Documentation/userspace-api/media/v4l/vidioc-enumaudio.rst
@@ -0,0 +1,53 @@
+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+.. c:namespace:: V4L
+
+.. _VIDIOC_ENUMAUDIO:
+
+**********************
+ioctl VIDIOC_ENUMAUDIO
+**********************
+
+Name
+====
+
+VIDIOC_ENUMAUDIO - Enumerate audio inputs
+
+Synopsis
+========
+
+.. c:macro:: VIDIOC_ENUMAUDIO
+
+``int ioctl(int fd, VIDIOC_ENUMAUDIO, struct v4l2_audio *argp)``
+
+Arguments
+=========
+
+``fd``
+ File descriptor returned by :c:func:`open()`.
+
+``argp``
+ Pointer to struct :c:type:`v4l2_audio`.
+
+Description
+===========
+
+To query the attributes of an audio input applications initialize the
+``index`` field and zero out the ``reserved`` array of a struct
+:c:type:`v4l2_audio` and call the :ref:`VIDIOC_ENUMAUDIO`
+ioctl with a pointer to this structure. Drivers fill the rest of the
+structure or return an ``EINVAL`` error code when the index is out of
+bounds. To enumerate all audio inputs applications shall begin at index
+zero, incrementing by one until the driver returns ``EINVAL``.
+
+See :ref:`VIDIOC_G_AUDIO <VIDIOC_G_AUDIO>` for a description of struct
+:c:type:`v4l2_audio`.
+
+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 <gen-errors>` chapter.
+
+EINVAL
+ The number of the audio input is out of bounds.