doc_rst: rename the media Sphinx suff to Documentation/media

The name of the subsystem is "media", and not "linux_tv". Also,
as we plan to add other stuff there in the future, let's
rename also the media uAPI book to media_uapi, to make it
clearer.

No functional changes.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

1 files changed, 51 insertions, 0 deletions

diff --git a/Documentation/media/uapi/v4l/io.rst b/Documentation/media/uapi/v4l/io.rst
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+.. -*- coding: utf-8; mode: rst -*-
+
+.. _io:
+
+############
+Input/Output
+############
+The V4L2 API defines several different methods to read from or write to
+a device. All drivers exchanging data with applications must support at
+least one of them.
+
+The classic I/O method using the :ref:`read() <func-read>` and
+:ref:`write() <func-write>` function is automatically selected after opening a
+V4L2 device. When the driver does not support this method attempts to
+read or write will fail at any time.
+
+Other methods must be negotiated. To select the streaming I/O method
+with memory mapped or user buffers applications call the
+:ref:`VIDIOC_REQBUFS` ioctl. The asynchronous I/O
+method is not defined yet.
+
+Video overlay can be considered another I/O method, although the
+application does not directly receive the image data. It is selected by
+initiating video overlay with the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>`
+ioctl. For more information see :ref:`overlay`.
+
+Generally exactly one I/O method, including overlay, is associated with
+each file descriptor. The only exceptions are applications not
+exchanging data with a driver ("panel applications", see :ref:`open`)
+and drivers permitting simultaneous video capturing and overlay using
+the same file descriptor, for compatibility with V4L and earlier
+versions of V4L2.
+
+:ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` and :ref:`VIDIOC_REQBUFS` would permit this to some
+degree, but for simplicity drivers need not support switching the I/O
+method (after first switching away from read/write) other than by
+closing and reopening the device.
+
+The following sections describe the various I/O methods in more detail.
+
+
+.. toctree::
+    :maxdepth: 1
+
+    rw
+    mmap
+    userp
+    dmabuf
+    async
+    buffer
+    field-order