[PATCH] pipeline_handler: Fix unlocking media devices too early when there are multiple cameras

[Laurent Pinchart]

Hi Hans,

Thank you for the patch.

On Sun, Aug 18, 2024 at 05:43:24PM +0200, Hans de Goede wrote:
> PipelineHandler::acquire() only locks the media devices when the first
> camera is acquired. If a second camera of a pipeline is acquired only
> useCount_ is increased and nothing else is done.
> 
> When releasing cameras PipelineHandler::release() should only unlock
> the media devices when the last camera is released. But the old code
> unlocked on every release().
> 
> Fix PipelineHandler::release() to only release the media devices when
> the last camera is released.
> 
> Signed-off-by: Hans de Goede <hdegoede at redhat.com>

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

> ---
>  src/libcamera/pipeline_handler.cpp | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp
> index 5a6de685..a20cd27d 100644
> --- a/src/libcamera/pipeline_handler.cpp
> +++ b/src/libcamera/pipeline_handler.cpp
> @@ -205,7 +205,8 @@ void PipelineHandler::release(Camera *camera)
>  
>  	ASSERT(useCount_);
>  
> -	unlockMediaDevices();
> +	if (useCount_ == 1)
> +		unlockMediaDevices();
>  
>  	releaseDevice(camera);
>  

-- 
Regards,

Laurent Pinchart