[libcamera-devel] [PATCH 3/3] ipa: raspberrypi: Update sensor's V4L2_CID_NOTIFY_GAINS control when present

[Laurent Pinchart]

Hi David,

Thank you for the patch.

On Thu, Dec 23, 2021 at 08:01:10AM +0000, David Plowman wrote:
> If the sensor exposes the V4L2_CID_NOTIFY_GAINS controls, assume it
> wants to be told the colour gains.
> 
> We want these to be applied as soon as possible so we add a new
> setSensorControls signal to the IPA which passes these back to the
> pipeline handler without using the DelayedControls mechanism.
> 
> Signed-off-by: David Plowman <david.plowman at raspberrypi.com>
> ---
>  include/libcamera/ipa/raspberrypi.mojom       |  1 +
>  src/ipa/raspberrypi/raspberrypi.cpp           | 22 +++++++++++++++++++
>  .../pipeline/raspberrypi/raspberrypi.cpp      | 10 +++++++++
>  3 files changed, 33 insertions(+)
> 
> diff --git a/include/libcamera/ipa/raspberrypi.mojom b/include/libcamera/ipa/raspberrypi.mojom
> index acd3cafe..e7647724 100644
> --- a/include/libcamera/ipa/raspberrypi.mojom
> +++ b/include/libcamera/ipa/raspberrypi.mojom
> @@ -123,6 +123,7 @@ interface IPARPiEventInterface {
>  	statsMetadataComplete(uint32 bufferId, libcamera.ControlList controls);
>  	runIsp(uint32 bufferId);
>  	embeddedComplete(uint32 bufferId);
> +	setSensorControls(libcamera.ControlList controls);
>  	setIspControls(libcamera.ControlList controls);
>  	setDelayedControls(libcamera.ControlList controls);
>  };
> diff --git a/src/ipa/raspberrypi/raspberrypi.cpp b/src/ipa/raspberrypi/raspberrypi.cpp
> index 0ed41385..8c20c066 100644
> --- a/src/ipa/raspberrypi/raspberrypi.cpp
> +++ b/src/ipa/raspberrypi/raspberrypi.cpp
> @@ -1061,6 +1061,28 @@ void IPARPi::processStats(unsigned int bufferId)
>  
>  		setDelayedControls.emit(ctrls);
>  	}
> +
> +	auto itCtrl = sensorCtrls_.find(V4L2_CID_NOTIFY_GAINS);
> +	if (itCtrl != sensorCtrls_.end()) {
> +		struct AwbStatus awbStatus;
> +		if (rpiMetadata_.Get("awb.status", awbStatus) == 0) {
> +			/*
> +			 * This control is a linear gain value where the default is
> +			 * defined to correspond to a gain of 1. The order of the gains
> +			 * is always B, Gb, Gr, R.
> +			 */
> +			int unity = itCtrl->second.def().get<int32_t>();
> +			ControlList ctrls(sensorCtrls_);
> +			int32_t gains[4] = { static_cast<int32_t>(awbStatus.gain_b * unity),
> +					     unity, unity,
> +					     static_cast<int32_t>(awbStatus.gain_r * unity) };
> +			ControlValue c(Span<const uint8_t>{ reinterpret_cast<uint8_t *>(gains),
> +							    sizeof(gains) });
> +			ctrls.set(V4L2_CID_NOTIFY_GAINS, c);
> +
> +			setSensorControls.emit(ctrls);

Could we avoid adding another operation by setting V4L2_CID_NOTIFY_GAINS
in the pipeline handler, when receiving the request metadata in
RPiCameraData::statsMetadataComplete() ?

> +		}
> +	}
>  }
>  
>  void IPARPi::applyAWB(const struct AwbStatus *awbStatus, ControlList &ctrls)
> diff --git a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> index b5c687da..59d3bbd8 100644
> --- a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> +++ b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> @@ -196,6 +196,7 @@ public:
>  	void statsMetadataComplete(uint32_t bufferId, const ControlList &controls);
>  	void runIsp(uint32_t bufferId);
>  	void embeddedComplete(uint32_t bufferId);
> +	void setSensorControls(const ControlList &controls);
>  	void setIspControls(const ControlList &controls);
>  	void setDelayedControls(const ControlList &controls);
>  	void setSensorControls(ControlList &controls);
> @@ -1405,6 +1406,7 @@ int RPiCameraData::loadIPA(ipa::RPi::SensorConfig *sensorConfig)
>  	ipa_->statsMetadataComplete.connect(this, &RPiCameraData::statsMetadataComplete);
>  	ipa_->runIsp.connect(this, &RPiCameraData::runIsp);
>  	ipa_->embeddedComplete.connect(this, &RPiCameraData::embeddedComplete);
> +	ipa_->setSensorControls.connect(this, &RPiCameraData::setSensorControls);
>  	ipa_->setIspControls.connect(this, &RPiCameraData::setIspControls);
>  	ipa_->setDelayedControls.connect(this, &RPiCameraData::setDelayedControls);
>  
> @@ -1524,6 +1526,14 @@ void RPiCameraData::embeddedComplete(uint32_t bufferId)
>  	handleState();
>  }
>  
> +void RPiCameraData::setSensorControls(const ControlList &controls)
> +{
> +	ControlList ctrls = controls;
> +
> +	sensor_->setControls(&ctrls);
> +	handleState();

Do we need to call handleState() here ?

> +}
> +
>  void RPiCameraData::setIspControls(const ControlList &controls)
>  {
>  	ControlList ctrls = controls;

-- 
Regards,

Laurent Pinchart