Commit 4e03cb76 authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab
Browse files

doc-rst: linux_tv: don't simplify VIDIOC_G_foo references



As VIDIOC_G_foo is the reference used for VIDIOC_S_foo and
VIDIOC_TRY_foo, we need to explicitly name the reference, as
otherwise, it will mention the three ioctls altogether, with
is not what we want.

Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
parent 2212ff25
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+1 −1
Original line number Original line Diff line number Diff line
@@ -16,7 +16,7 @@ applications and automatically regain control of the device at a later
time.
time.


Since these features cannot be implemented entirely in user space V4L2
Since these features cannot be implemented entirely in user space V4L2
defines the :ref:`VIDIOC_G_PRIORITY` and
defines the :ref:`VIDIOC_G_PRIORITY <VIDIOC_G_PRIORITY>` and
:ref:`VIDIOC_S_PRIORITY <VIDIOC_G_PRIORITY>` ioctls to request and
:ref:`VIDIOC_S_PRIORITY <VIDIOC_G_PRIORITY>` ioctls to request and
query the access priority associate with a file descriptor. Opening a
query the access priority associate with a file descriptor. Opening a
device assigns a medium priority, compatible with earlier versions of
device assigns a medium priority, compatible with earlier versions of
+3 −3
Original line number Original line Diff line number Diff line
@@ -33,11 +33,11 @@ The struct :ref:`v4l2_audio <v4l2-audio>` returned by the
:ref:`VIDIOC_ENUMAUDIO` ioctl also contains signal
:ref:`VIDIOC_ENUMAUDIO` ioctl also contains signal
:status information applicable when the current audio input is queried.
:status information applicable when the current audio input is queried.


The :ref:`VIDIOC_G_AUDIO` and
The :ref:`VIDIOC_G_AUDIO <VIDIOC_G_AUDIO>` and
:ref:`VIDIOC_G_AUDOUT <VIDIOC_G_AUDIOout>` ioctls report the current
:ref:`VIDIOC_G_AUDOUT <VIDIOC_G_AUDIOout>` ioctls report the current
audio input and output, respectively. Note that, unlike
audio input and output, respectively. Note that, unlike
:ref:`VIDIOC_G_INPUT` and
:ref:`VIDIOC_G_INPUT <VIDIOC_G_INPUT>` and
:ref:`VIDIOC_G_OUTPUT` these ioctls return a
:ref:`VIDIOC_G_OUTPUT <VIDIOC_G_OUTPUT>` these ioctls return a
structure as :ref:`VIDIOC_ENUMAUDIO` and
structure as :ref:`VIDIOC_ENUMAUDIO` and
:ref:`VIDIOC_ENUMAUDOUT <VIDIOC_ENUMAUDIOout>` do, not just an index.
:ref:`VIDIOC_ENUMAUDOUT <VIDIOC_ENUMAUDIOout>` do, not just an index.


+1 −1
Original line number Original line Diff line number Diff line
@@ -364,7 +364,7 @@ Control IDs
Applications can enumerate the available controls with the
Applications can enumerate the available controls with the
:ref:`VIDIOC_QUERYCTRL` and
:ref:`VIDIOC_QUERYCTRL` and
:ref:`VIDIOC_QUERYMENU <VIDIOC_QUERYCTRL>` ioctls, get and set a
:ref:`VIDIOC_QUERYMENU <VIDIOC_QUERYCTRL>` ioctls, get and set a
control value with the :ref:`VIDIOC_G_CTRL` and
control value with the :ref:`VIDIOC_G_CTRL <VIDIOC_G_CTRL>` and
:ref:`VIDIOC_S_CTRL <VIDIOC_G_CTRL>` ioctls. Drivers must implement
:ref:`VIDIOC_S_CTRL <VIDIOC_G_CTRL>` ioctls. Drivers must implement
``VIDIOC_QUERYCTRL``, ``VIDIOC_G_CTRL`` and ``VIDIOC_S_CTRL`` when the
``VIDIOC_QUERYCTRL``, ``VIDIOC_G_CTRL`` and ``VIDIOC_S_CTRL`` when the
device has one or more controls, ``VIDIOC_QUERYMENU`` when it has one or
device has one or more controls, ``VIDIOC_QUERYMENU`` when it has one or
+2 −2
Original line number Original line Diff line number Diff line
@@ -15,7 +15,7 @@ offset into a video signal.
Applications can use the following API to select an area in the video
Applications can use the following API to select an area in the video
signal, query the default area and the hardware limits. *Despite their
signal, query the default area and the hardware limits. *Despite their
name, the :ref:`VIDIOC_CROPCAP`,
name, the :ref:`VIDIOC_CROPCAP`,
:ref:`VIDIOC_G_CROP` and
:ref:`VIDIOC_G_CROP <VIDIOC_G_CROP>` and
:ref:`VIDIOC_S_CROP <VIDIOC_G_CROP>` ioctls apply to input as well
:ref:`VIDIOC_S_CROP <VIDIOC_G_CROP>` ioctls apply to input as well
as output devices.*
as output devices.*


@@ -23,7 +23,7 @@ Scaling requires a source and a target. On a video capture or overlay
device the source is the video signal, and the cropping ioctls determine
device the source is the video signal, and the cropping ioctls determine
the area actually sampled. The target are images read by the application
the area actually sampled. The target are images read by the application
or overlaid onto the graphics screen. Their size (and position for an
or overlaid onto the graphics screen. Their size (and position for an
overlay) is negotiated with the :ref:`VIDIOC_G_FMT`
overlay) is negotiated with the :ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>`
and :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctls.
and :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctls.


On a video output device the source are the images passed in by the
On a video output device the source are the images passed in by the
+6 −6
Original line number Original line Diff line number Diff line
@@ -65,7 +65,7 @@ To query the current image format applications set the ``type`` field of
a struct :ref:`v4l2_format <v4l2-format>` to
a struct :ref:`v4l2_format <v4l2-format>` to
``V4L2_BUF_TYPE_VIDEO_CAPTURE`` or
``V4L2_BUF_TYPE_VIDEO_CAPTURE`` or
``V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE`` and call the
``V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE`` and call the
:ref:`VIDIOC_G_FMT` ioctl with a pointer to this
:ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>` ioctl with a pointer to this
structure. Drivers fill the struct
structure. Drivers fill the struct
:ref:`v4l2_pix_format <v4l2-pix-format>` ``pix`` or the struct
:ref:`v4l2_pix_format <v4l2-pix-format>` ``pix`` or the struct
:ref:`v4l2_pix_format_mplane <v4l2-pix-format-mplane>` ``pix_mp``
:ref:`v4l2_pix_format_mplane <v4l2-pix-format-mplane>` ``pix_mp``
@@ -75,9 +75,9 @@ To request different parameters applications set the ``type`` field of a
struct :ref:`v4l2_format <v4l2-format>` as above and initialize all
struct :ref:`v4l2_format <v4l2-format>` as above and initialize all
fields of the struct :ref:`v4l2_pix_format <v4l2-pix-format>`
fields of the struct :ref:`v4l2_pix_format <v4l2-pix-format>`
``vbi`` member of the ``fmt`` union, or better just modify the results
``vbi`` member of the ``fmt`` union, or better just modify the results
of :ref:`VIDIOC_G_FMT`, and call the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>`
of :ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>`, and call the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>`
ioctl with a pointer to this structure. Drivers may adjust the
ioctl with a pointer to this structure. Drivers may adjust the
parameters and finally return the actual parameters as :ref:`VIDIOC_G_FMT`
parameters and finally return the actual parameters as :ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>`
does.
does.


Like :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` the :ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>` ioctl
Like :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` the :ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>` ioctl
@@ -87,10 +87,10 @@ possibly time consuming hardware preparations.
The contents of struct :ref:`v4l2_pix_format <v4l2-pix-format>` and
The contents of struct :ref:`v4l2_pix_format <v4l2-pix-format>` and
struct :ref:`v4l2_pix_format_mplane <v4l2-pix-format-mplane>` are
struct :ref:`v4l2_pix_format_mplane <v4l2-pix-format-mplane>` are
discussed in :ref:`pixfmt`. See also the specification of the
discussed in :ref:`pixfmt`. See also the specification of the
:ref:`VIDIOC_G_FMT`, :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` and :ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>` ioctls for
:ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>`, :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` and :ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>` ioctls for
details. Video capture devices must implement both the :ref:`VIDIOC_G_FMT`
details. Video capture devices must implement both the :ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>`
and :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl, even if :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ignores all
and :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl, even if :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ignores all
requests and always returns default parameters as :ref:`VIDIOC_G_FMT` does.
requests and always returns default parameters as :ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>` does.
:ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>` is optional.
:ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>` is optional.




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