[libcamera-devel] [PATCH v5 08/19] libcamera: ipu3: Cache the camera sizes

[Laurent Pinchart]

Hi Jacopo,

Thank you for the patch.

On Tue, Mar 26, 2019 at 09:38:51AM +0100, Jacopo Mondi wrote:
> When creating a camera, make sure a the image sensor provides images in
> a format compatible with IPU3 CIO2 unit requirements and cache the
> minimum and maximum camera sizes.
> 
> Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
> ---
>  src/libcamera/pipeline/ipu3/ipu3.cpp | 56 +++++++++++++++++++++++++++-
>  1 file changed, 54 insertions(+), 2 deletions(-)
> 
> diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
> index 55489c31df2d..d42c81273cc6 100644
> --- a/src/libcamera/pipeline/ipu3/ipu3.cpp
> +++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
> @@ -8,11 +8,14 @@
>  #include <memory>
>  #include <vector>
>  
> +#include <linux/media-bus-format.h>
> +
>  #include <libcamera/camera.h>
>  #include <libcamera/request.h>
>  #include <libcamera/stream.h>
>  
>  #include "device_enumerator.h"
> +#include "geometry.h"
>  #include "log.h"
>  #include "media_device.h"
>  #include "pipeline_handler.h"
> @@ -24,6 +27,22 @@ namespace libcamera {
>  
>  LOG_DEFINE_CATEGORY(IPU3)
>  
> +static int mediaBusToCIO2Format(unsigned int code)
> +{
> +	switch (code) {
> +	case MEDIA_BUS_FMT_SBGGR10_1X10:
> +		return V4L2_PIX_FMT_IPU3_SBGGR10;
> +	case MEDIA_BUS_FMT_SGBRG10_1X10:
> +		return V4L2_PIX_FMT_IPU3_SGBRG10;
> +	case MEDIA_BUS_FMT_SGRBG10_1X10:
> +		return V4L2_PIX_FMT_IPU3_SGRBG10;
> +	case MEDIA_BUS_FMT_SRGGB10_1X10:
> +		return V4L2_PIX_FMT_IPU3_SRGGB10;
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
>  class PipelineHandlerIPU3 : public PipelineHandler
>  {
>  public:
> @@ -70,6 +89,9 @@ private:
>  		V4L2Subdevice *sensor_;
>  
>  		Stream stream_;
> +
> +		/* Maximum sizes and the mbus code used to produce them. */
> +		std::pair<unsigned int, SizeRange> maxSizes_;

The use of std::pair here makes the code below use .first and .second,
which are not very readable. I think it would be better to store the
pixel format and max size in two separate fields, of unsigned int and
SizeRange types respectively. Or, now that I think about it, as you only
care about the maximum size, maybe adding a Size structure to geometry.h
would be a good idea.

>  	};
>  
>  	IPU3CameraData *cameraData(const Camera *camera)
> @@ -404,18 +426,48 @@ void PipelineHandlerIPU3::registerCameras()
>  		if (ret)
>  			continue;
>  
> -		data->cio2_->bufferReady.connect(data.get(), &IPU3CameraData::bufferReady);
> -
> +		/*
> +		 * Make sure the sensor produces at least one image format
> +		 * compatible with IPU3 CIO2 requirements and cache the camera
> +		 * maximum sizes.
> +		 */
>  		data->sensor_ = new V4L2Subdevice(sensor);
>  		ret = data->sensor_->open();
>  		if (ret)
>  			continue;
>  
> +		for (auto it : data->sensor_->formats(0)) {
> +			int mbusCode = mediaBusToCIO2Format(it.first);
> +			if (mbusCode < 0)
> +				continue;
> +
> +			for (const SizeRange &size : it.second) {
> +				SizeRange &maxSize = data->maxSizes_.second;
> +
> +				if (maxSize.maxWidth < size.maxWidth &&
> +				    maxSize.maxHeight < size.maxHeight) {
> +					maxSize.maxWidth = size.maxWidth;
> +					maxSize.maxHeight = size.maxHeight;
> +					data->maxSizes_.first = mbusCode;
> +				}
> +			}
> +		}

One blank line ?

> +		if (data->maxSizes_.second.maxWidth == 0) {
> +			LOG(IPU3, Info)
> +				<< "Sensor '" << data->sensor_->entityName()
> +				<< "' detected, but no supported image format "
> +				<< " found: skip camera creation";
> +			continue;
> +		}
> +
>  		data->csi2_ = new V4L2Subdevice(csi2);
>  		ret = data->csi2_->open();
>  		if (ret)
>  			continue;
>  
> +		data->cio2_->bufferReady.connect(data.get(),
> +						 &IPU3CameraData::bufferReady);
> +

This seems unrelated to this patch, is it needed ?

>  		registerCamera(std::move(camera), std::move(data));
>  
>  		LOG(IPU3, Info)

-- 
Regards,

Laurent Pinchart