media: docs: move uAPI book to userspace-api/media

Since 2017, there is an space reserved for userspace API,
created by changeset 1d596dee3862 ("docs: Create a user-space API guide").

As the media subsystem was one of the first subsystems to use
Sphinx, until this patch, we were keeping things on a separate
place.

Let's just use the new location, as having all uAPI altogether
will likely make things easier for developers.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

1 files changed, 0 insertions, 125 deletions

diff --git a/Documentation/media/uapi/dvb/dmx-mmap.rst b/Documentation/media/uapi/dvb/dmx-mmap.rst
deleted file mode 100644
index 34bb7766718f..000000000000
--- a/Documentation/media/uapi/dvb/dmx-mmap.rst
+++ /dev/null
@@ -1,125 +0,0 @@
-.. Permission is granted to copy, distribute and/or modify this
-.. document under the terms of the GNU Free Documentation License,
-.. Version 1.1 or any later version published by the Free Software
-.. Foundation, with no Invariant Sections, no Front-Cover Texts
-.. and no Back-Cover Texts. A copy of the license is included at
-.. Documentation/media/uapi/fdl-appendix.rst.
-..
-.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
-
-.. _dmx-mmap:
-
-*****************
-Digital TV mmap()
-*****************
-
-Name
-====
-
-dmx-mmap - Map device memory into application address space
-
-.. warning:: this API is still experimental
-
-Synopsis
-========
-
-.. code-block:: c
-
-    #include <unistd.h>
-    #include <sys/mman.h>
-
-
-.. c:function:: void *mmap( void *start, size_t length, int prot, int flags, int fd, off_t offset )
-    :name: dmx-mmap
-
-Arguments
-=========
-
-``start``
-    Map the buffer to this address in the application's address space.
-    When the ``MAP_FIXED`` flag is specified, ``start`` must be a
-    multiple of the pagesize and mmap will fail when the specified
-    address cannot be used. Use of this option is discouraged;
-    applications should just specify a ``NULL`` pointer here.
-
-``length``
-    Length of the memory area to map. This must be a multiple of the
-    DVB packet length (188, on most drivers).
-
-``prot``
-    The ``prot`` argument describes the desired memory protection.
-    Regardless of the device type and the direction of data exchange it
-    should be set to ``PROT_READ`` | ``PROT_WRITE``, permitting read
-    and write access to image buffers. Drivers should support at least
-    this combination of flags.
-
-``flags``
-    The ``flags`` parameter specifies the type of the mapped object,
-    mapping options and whether modifications made to the mapped copy of
-    the page are private to the process or are to be shared with other
-    references.
-
-    ``MAP_FIXED`` requests that the driver selects no other address than
-    the one specified. If the specified address cannot be used,
-    :ref:`mmap() <dmx-mmap>` will fail. If ``MAP_FIXED`` is specified,
-    ``start`` must be a multiple of the pagesize. Use of this option is
-    discouraged.
-
-    One of the ``MAP_SHARED`` or ``MAP_PRIVATE`` flags must be set.
-    ``MAP_SHARED`` allows applications to share the mapped memory with
-    other (e. g. child-) processes.
-
-    .. note::
-
-       The Linux Digital TV applications should not set the
-       ``MAP_PRIVATE``, ``MAP_DENYWRITE``, ``MAP_EXECUTABLE`` or ``MAP_ANON``
-       flags.
-
-``fd``
-    File descriptor returned by :ref:`open() <dmx_fopen>`.
-
-``offset``
-    Offset of the buffer in device memory, as returned by
-    :ref:`DMX_QUERYBUF` ioctl.
-
-
-Description
-===========
-
-The :ref:`mmap() <dmx-mmap>` function asks to map ``length`` bytes starting at
-``offset`` in the memory of the device specified by ``fd`` into the
-application address space, preferably at address ``start``. This latter
-address is a hint only, and is usually specified as 0.
-
-Suitable length and offset parameters are queried with the
-:ref:`DMX_QUERYBUF` ioctl. Buffers must be allocated with the
-:ref:`DMX_REQBUFS` ioctl before they can be queried.
-
-To unmap buffers the :ref:`munmap() <dmx-munmap>` function is used.
-
-
-Return Value
-============
-
-On success :ref:`mmap() <dmx-mmap>` returns a pointer to the mapped buffer. On
-error ``MAP_FAILED`` (-1) is returned, and the ``errno`` variable is set
-appropriately. Possible error codes are:
-
-EBADF
-    ``fd`` is not a valid file descriptor.
-
-EACCES
-    ``fd`` is not open for reading and writing.
-
-EINVAL
-    The ``start`` or ``length`` or ``offset`` are not suitable. (E. g.
-    they are too large, or not aligned on a ``PAGESIZE`` boundary.)
-
-    The ``flags`` or ``prot`` value is not supported.
-
-    No buffers have been allocated with the
-    :ref:`DMX_REQBUFS` ioctl.
-
-ENOMEM
-    Not enough physical or virtual memory was available to complete the
-    request.