[libcamera-devel] [PATCH] libcamera: camera_data: Document requestSequence_

[Laurent Pinchart]

Hi Jacopo,

Thank you for the patch.

On Wed, Apr 07, 2021 at 04:10:41PM +0200, Jacopo Mondi wrote:
> The CameraData::requestSequence_ field was not documented. Fix it.

The only thing worse than pushing to production on a Friday is pushing
to production just before a week of holiday :-) Kieran said he would fix
this (and the other doxygen warnings introduced at the same time) when
coming back.

> Also remove an empty line the class declaration as the field is not
> special compared to the other existing ones.
> 
> Fixes the doxygen warning
> /include/libcamera/internal/pipeline_handler.h:51: warning: Member
> requestSequence_ (variable) of class libcamera::CameraData is not
> documented.
> 

A Fixes: line could be nice.

> Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
> 
> ---
> Isn't it a bit fishy that the counter is never reset ?

It's on purpose, to uniquely identify requests across stop()/start()
sequences.

> ---
>  include/libcamera/internal/pipeline_handler.h | 1 -
>  src/libcamera/pipeline_handler.cpp            | 8 ++++++++
>  2 files changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/include/libcamera/internal/pipeline_handler.h b/include/libcamera/internal/pipeline_handler.h
> index c6454db6b2c4..82fdc1fee9b9 100644
> --- a/include/libcamera/internal/pipeline_handler.h
> +++ b/include/libcamera/internal/pipeline_handler.h
> @@ -47,7 +47,6 @@ public:
>  	std::list<Request *> queuedRequests_;
>  	ControlInfoMap controlInfo_;
>  	ControlList properties_;
> -
>  	uint32_t requestSequence_;
> 
>  private:
> diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp
> index 433c05f60db0..7f4fa1b4ba89 100644
> --- a/src/libcamera/pipeline_handler.cpp
> +++ b/src/libcamera/pipeline_handler.cpp
> @@ -97,6 +97,14 @@ LOG_DEFINE_CATEGORY(Pipeline)
>   * when creating the camera, and shall not be modified afterwards.
>   */
> 
> +/**
> + * \var CameraData::requestSequence_
> + * \brief The request sequence counter
> + *
> + * The request sequence counter is increased when a new Request is queued to
> + * the camera and monotonically increases during the whole library lifetime.

It's actually the lifetime of the camera.

It would be good to also document the purpose of this field.

> + */
> +
>  /**
>   * \class PipelineHandler
>   * \brief Create and manage cameras based on a set of media devices

-- 
Regards,

Laurent Pinchart