Re: [PATCH/RFC v13 10/13] Documentation: leds: Add description of v4l2-flash sub-device
From: Sakari Ailus
Date: Wed Mar 18 2015 - 08:40:38 EST
Hi Jacek,
On Thu, Mar 12, 2015 at 04:45:11PM +0100, Jacek Anaszewski wrote:
> This patch extends LED Flash class documention by
> the description of interactions with v4l2-flash sub-device.
>
> Signed-off-by: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx>
> Acked-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
> Acked-by: Sakari Ailus <sakari.ailus@xxxxxx>
> Cc: Bryan Wu <cooloney@xxxxxxxxx>
> Cc: Richard Purdie <rpurdie@xxxxxxxxx>
> ---
> Documentation/leds/leds-class-flash.txt | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/Documentation/leds/leds-class-flash.txt b/Documentation/leds/leds-class-flash.txt
> index 19bb673..8623413 100644
> --- a/Documentation/leds/leds-class-flash.txt
> +++ b/Documentation/leds/leds-class-flash.txt
> @@ -20,3 +20,16 @@ Following sysfs attributes are exposed for controlling flash LED devices:
> - max_flash_timeout
> - flash_strobe
> - flash_fault
> +
> +A LED subsystem driver can be controlled also from the level of VideoForLinux2
> +subsystem. In order to enable this CONFIG_V4L2_FLASH_LED_CLASS symbol has to
> +be defined in the kernel config. The driver must call the v4l2_flash_init
> +function to get registered in the V4L2 subsystem. On remove the
> +v4l2_flash_release function has to be called (see <media/v4l2-flash.h>).
> +
> +After proper initialization a V4L2 Flash sub-device is created. The sub-device
> +exposes a number of V4L2 controls, which allow for controlling a LED Flash class
Over 80 characters per line.
With this fixed,
Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> +device with use of its internal kernel API.
> +Opening the V4L2 Flash sub-device makes the LED subsystem sysfs interface
> +unavailable. The interface is re-enabled after the V4L2 Flash sub-device
> +is closed.
--
Kind regards,
Sakari Ailus
e-mail: sakari.ailus@xxxxxx XMPP: sailus@xxxxxxxxxxxxxx
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