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, 204 insertions, 0 deletions

diff --git a/Documentation/media/uapi/v4l/vidioc-dbg-g-chip-info.rst b/Documentation/media/uapi/v4l/vidioc-dbg-g-chip-info.rst
new file mode 100644
index 000000000000..efa911c0fb19
--- /dev/null
+++ b/Documentation/media/uapi/v4l/vidioc-dbg-g-chip-info.rst
@@ -0,0 +1,204 @@
+.. -*- coding: utf-8; mode: rst -*-
+
+.. _VIDIOC_DBG_G_CHIP_INFO:
+
+****************************
+ioctl VIDIOC_DBG_G_CHIP_INFO
+****************************
+
+Name
+====
+
+VIDIOC_DBG_G_CHIP_INFO - Identify the chips on a TV card
+
+
+Synopsis
+========
+
+.. cpp:function:: int ioctl( int fd, int request, struct v4l2_dbg_chip_info *argp )
+
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :ref:`open() <func-open>`.
+
+``request``
+    VIDIOC_DBG_G_CHIP_INFO
+
+``argp``
+
+
+Description
+===========
+
+    **Note**
+
+    This is an :ref:`experimental` interface and may
+    change in the future.
+
+For driver debugging purposes this ioctl allows test applications to
+query the driver about the chips present on the TV card. Regular
+applications must not use it. When you found a chip specific bug, please
+contact the linux-media mailing list
+(`https://linuxtv.org/lists.php <https://linuxtv.org/lists.php>`__)
+so it can be fixed.
+
+Additionally the Linux kernel must be compiled with the
+``CONFIG_VIDEO_ADV_DEBUG`` option to enable this ioctl.
+
+To query the driver applications must initialize the ``match.type`` and
+``match.addr`` or ``match.name`` fields of a struct
+:ref:`v4l2_dbg_chip_info <v4l2-dbg-chip-info>` and call
+:ref:`VIDIOC_DBG_G_CHIP_INFO` with a pointer to this structure. On success
+the driver stores information about the selected chip in the ``name``
+and ``flags`` fields.
+
+When ``match.type`` is ``V4L2_CHIP_MATCH_BRIDGE``, ``match.addr``
+selects the nth bridge 'chip' on the TV card. You can enumerate all
+chips by starting at zero and incrementing ``match.addr`` by one until
+:ref:`VIDIOC_DBG_G_CHIP_INFO` fails with an ``EINVAL`` error code. The number
+zero always selects the bridge chip itself, e. g. the chip connected to
+the PCI or USB bus. Non-zero numbers identify specific parts of the
+bridge chip such as an AC97 register block.
+
+When ``match.type`` is ``V4L2_CHIP_MATCH_SUBDEV``, ``match.addr``
+selects the nth sub-device. This allows you to enumerate over all
+sub-devices.
+
+On success, the ``name`` field will contain a chip name and the
+``flags`` field will contain ``V4L2_CHIP_FL_READABLE`` if the driver
+supports reading registers from the device or ``V4L2_CHIP_FL_WRITABLE``
+if the driver supports writing registers to the device.
+
+We recommended the v4l2-dbg utility over calling this ioctl directly. It
+is available from the LinuxTV v4l-dvb repository; see
+`https://linuxtv.org/repo/ <https://linuxtv.org/repo/>`__ for access
+instructions.
+
+
+.. _name-v4l2-dbg-match:
+
+.. flat-table:: struct v4l2_dbg_match
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 1 1 2
+
+
+    -  .. row 1
+
+       -  __u32
+
+       -  ``type``
+
+       -  See :ref:`name-chip-match-types` for a list of possible types.
+
+    -  .. row 2
+
+       -  union
+
+       -  (anonymous)
+
+    -  .. row 3
+
+       -
+       -  __u32
+
+       -  ``addr``
+
+       -  Match a chip by this number, interpreted according to the ``type``
+	  field.
+
+    -  .. row 4
+
+       -
+       -  char
+
+       -  ``name[32]``
+
+       -  Match a chip by this name, interpreted according to the ``type``
+	  field. Currently unused.
+
+
+
+.. _v4l2-dbg-chip-info:
+
+.. flat-table:: struct v4l2_dbg_chip_info
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 1 2
+
+
+    -  .. row 1
+
+       -  struct v4l2_dbg_match
+
+       -  ``match``
+
+       -  How to match the chip, see :ref:`name-v4l2-dbg-match`.
+
+    -  .. row 2
+
+       -  char
+
+       -  ``name[32]``
+
+       -  The name of the chip.
+
+    -  .. row 3
+
+       -  __u32
+
+       -  ``flags``
+
+       -  Set by the driver. If ``V4L2_CHIP_FL_READABLE`` is set, then the
+	  driver supports reading registers from the device. If
+	  ``V4L2_CHIP_FL_WRITABLE`` is set, then it supports writing
+	  registers.
+
+    -  .. row 4
+
+       -  __u32
+
+       -  ``reserved[8]``
+
+       -  Reserved fields, both application and driver must set these to 0.
+
+
+
+.. _name-chip-match-types:
+
+.. flat-table:: Chip Match Types
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       3 1 4
+
+
+    -  .. row 1
+
+       -  ``V4L2_CHIP_MATCH_BRIDGE``
+
+       -  0
+
+       -  Match the nth chip on the card, zero for the bridge chip. Does not
+	  match sub-devices.
+
+    -  .. row 2
+
+       -  ``V4L2_CHIP_MATCH_SUBDEV``
+
+       -  4
+
+       -  Match the nth sub-device.
+
+
+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 ``match_type`` is invalid or no device could be matched.