github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-06-01 02:53:36 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

Documentation: uAPI: media: add V4L2_CID_FLASH_{DURATION,STROBE_OE}

Browse Source 
Add the new strobe duration and hardware strobe output enable to v4l
uAPI documentation. Additionally add labels for cross-referencing v4l
controls.

Signed-off-by: Richard Leitner <richard.leitner@linux.dev>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
This commit is contained in:
Richard Leitner 2025-12-09 23:44:38 +01:00 committed by Hans Verkuil
parent 5be4154f62
commit fa0e06f2fe
1 changed files with 42 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
Documentation/userspace-api/media/v4l/ext-ctrls-flash.rst
View File

@ -58,6 +58,8 @@ Flash Control IDs
``V4L2_CID_FLASH_CLASS (class)``
The FLASH class descriptor.
.. _v4l2-cid-flash-led-mode:
``V4L2_CID_FLASH_LED_MODE (menu)``
Defines the mode of the flash LED, the high-power white LED attached
to the flash controller. Setting this control may not be possible in
@ -81,6 +83,8 @@ Flash Control IDs
.. _v4l2-cid-flash-strobe-source:
``V4L2_CID_FLASH_STROBE_SOURCE (menu)``
Defines the source of the flash LED strobe.
@ -97,6 +101,12 @@ Flash Control IDs
- The flash strobe is triggered by an external source. Typically
this is a sensor, which makes it possible to synchronise the
flash strobe start to exposure start.
This method of controlling flash LED strobe has two additional
prerequisites: the strobe source's :ref:`strobe output
<v4l2-cid-flash-strobe-oe>` must be enabled (if available)
and the flash controller's :ref:`flash LED mode
<v4l2-cid-flash-led-mode>` must be set to
``V4L2_FLASH_LED_MODE_FLASH``.
@ -187,3 +197,35 @@ Flash Control IDs
charged before strobing. LED flashes often require a cooldown period
after strobe during which another strobe will not be possible. This
is a read-only control.
.. _v4l2-cid-flash-duration:
``V4L2_CID_FLASH_DURATION (integer)``
Duration of the flash strobe pulse generated by the strobe source, when
using external strobe. This control shall be implemented by the device
generating the hardware flash strobe signal, typically a camera sensor,
connected to a flash controller.
The flash controllers :ref:`strobe source <v4l2-cid-flash-strobe-source>`
must be configured to ``V4L2_FLASH_STROBE_SOURCE_EXTERNAL`` for this
mode of operation. For more details please also take a look at the
documentation there.
The unit should be microseconds (µs) if possible.
.. _v4l2-cid-flash-strobe-oe:
``V4L2_CID_FLASH_STROBE_OE (boolean)``
Enables the output of a hardware strobe signal from the strobe source,
when using external strobe. This control shall be implemented by the device
generating the hardware flash strobe signal, typically a camera sensor,
connected to a flash controller.
Provided the signal generating device driver supports it, the length of the
strobe signal can be configured by adjusting its
:ref:`flash duration <v4l2-cid-flash-duration>`.
The flash controllers :ref:`strobe source <v4l2-cid-flash-strobe-source>`
must be configured to ``V4L2_FLASH_STROBE_SOURCE_EXTERNAL`` for this
mode of operation. For more details please also take a look at the
documentation there.