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, 136 insertions, 0 deletions

diff --git a/Documentation/media/uapi/v4l/vidioc-subdev-g-crop.rst b/Documentation/media/uapi/v4l/vidioc-subdev-g-crop.rst
new file mode 100644
index 000000000000..690034a391d3
--- /dev/null
+++ b/Documentation/media/uapi/v4l/vidioc-subdev-g-crop.rst
@@ -0,0 +1,136 @@
+.. -*- coding: utf-8; mode: rst -*-
+
+.. _VIDIOC_SUBDEV_G_CROP:
+
+************************************************
+ioctl VIDIOC_SUBDEV_G_CROP, VIDIOC_SUBDEV_S_CROP
+************************************************
+
+Name
+====
+
+VIDIOC_SUBDEV_G_CROP - VIDIOC_SUBDEV_S_CROP - Get or set the crop rectangle on a subdev pad
+
+
+Synopsis
+========
+
+.. cpp:function:: int ioctl( int fd, int request, struct v4l2_subdev_crop *argp )
+
+.. cpp:function:: int ioctl( int fd, int request, const struct v4l2_subdev_crop *argp )
+
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :ref:`open() <func-open>`.
+
+``request``
+    VIDIOC_SUBDEV_G_CROP, VIDIOC_SUBDEV_S_CROP
+
+``argp``
+
+
+Description
+===========
+
+    **Note**
+
+    This is an :ref:`obsolete` interface and may be removed
+    in the future. It is superseded by
+    :ref:`the selection API <VIDIOC_SUBDEV_G_SELECTION>`.
+
+To retrieve the current crop rectangle applications set the ``pad``
+field of a struct :ref:`v4l2_subdev_crop <v4l2-subdev-crop>` to the
+desired pad number as reported by the media API and the ``which`` field
+to ``V4L2_SUBDEV_FORMAT_ACTIVE``. They then call the
+``VIDIOC_SUBDEV_G_CROP`` ioctl with a pointer to this structure. The
+driver fills the members of the ``rect`` field or returns ``EINVAL`` error
+code if the input arguments are invalid, or if cropping is not supported
+on the given pad.
+
+To change the current crop rectangle applications set both the ``pad``
+and ``which`` fields and all members of the ``rect`` field. They then
+call the ``VIDIOC_SUBDEV_S_CROP`` ioctl with a pointer to this
+structure. The driver verifies the requested crop rectangle, adjusts it
+based on the hardware capabilities and configures the device. Upon
+return the struct :ref:`v4l2_subdev_crop <v4l2-subdev-crop>`
+contains the current format as would be returned by a
+``VIDIOC_SUBDEV_G_CROP`` call.
+
+Applications can query the device capabilities by setting the ``which``
+to ``V4L2_SUBDEV_FORMAT_TRY``. When set, 'try' crop rectangles are not
+applied to the device by the driver, but are mangled exactly as active
+crop rectangles and stored in the sub-device file handle. Two
+applications querying the same sub-device would thus not interact with
+each other.
+
+Drivers must not return an error solely because the requested crop
+rectangle doesn't match the device capabilities. They must instead
+modify the rectangle to match what the hardware can provide. The
+modified format should be as close as possible to the original request.
+
+
+.. _v4l2-subdev-crop:
+
+.. flat-table:: struct v4l2_subdev_crop
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 1 2
+
+
+    -  .. row 1
+
+       -  __u32
+
+       -  ``pad``
+
+       -  Pad number as reported by the media framework.
+
+    -  .. row 2
+
+       -  __u32
+
+       -  ``which``
+
+       -  Crop rectangle to get or set, from enum
+	  :ref:`v4l2_subdev_format_whence <v4l2-subdev-format-whence>`.
+
+    -  .. row 3
+
+       -  struct :ref:`v4l2_rect <v4l2-rect>`
+
+       -  ``rect``
+
+       -  Crop rectangle boundaries, in pixels.
+
+    -  .. row 4
+
+       -  __u32
+
+       -  ``reserved``\ [8]
+
+       -  Reserved for future extensions. Applications and drivers must set
+	  the array to zero.
+
+
+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.
+
+EBUSY
+    The crop rectangle can't be changed because the pad is currently
+    busy. This can be caused, for instance, by an active video stream on
+    the pad. The ioctl must not be retried without performing another
+    action to fix the problem first. Only returned by
+    ``VIDIOC_SUBDEV_S_CROP``
+
+EINVAL
+    The struct :ref:`v4l2_subdev_crop <v4l2-subdev-crop>` ``pad``
+    references a non-existing pad, the ``which`` field references a
+    non-existing format, or cropping is not supported on the given
+    subdev pad.