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Subject: Re: [PATCH] media: vimc: Make capture devices and subdevices use
 different link_validates
To:     =?UTF-8?B?TsOtY29sYXMgRi4gUi4gQS4gUHJhZG8=?= 
        <nfraprado@protonmail.com>, linux-media@vger.kernel.org
Cc:     Shuah Khan <skhan@linuxfoundation.org>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Hans Verkuil <hverkuil@xs4all.nl>,
        linux-kernel@vger.kernel.org, lkcamp@lists.libreplanetbr.org
References: <20191006191416.1130515-1-nfraprado@protonmail.com>
From:   Helen Koike <helen.koike@collabora.com>
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Message-ID: <c05cf7ac-a139-77ea-afbd-e210116d5d8b@collabora.com>
Date:   Sun, 6 Oct 2019 21:42:52 -0300
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Hi Nícolas,

Thanks for you patch, just some small comments below.

On 10/6/19 4:14 PM, Nícolas F. R. A. Prado wrote:
> Instead of validating the links to capture devices and subdevices with
> the same function, use the default v4l function for links between
> subdevices and only use a different function for validating between
> capture device and subdevice.
> This change should also ease future work to associate multiple mbus
> codes for the same pixelformat in vimc_pix_map.
> 
> These changes were tested with 
> v4l2-compliance SHA: 3f806630e2ecbcebe31872b865c5c4b42f111a99, 64 bits
> and passed all tests:
> Grand Total for vimc device /dev/media0: 451, Succeeded: 451, Failed: 0, Warnings: 0
> 
> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@protonmail.com>
> ---
>  drivers/media/platform/vimc/vimc-capture.c |  78 +++++++++++++++-
>  drivers/media/platform/vimc/vimc-common.c  | 103 ++++-----------------
>  drivers/media/platform/vimc/vimc-common.h  |   3 +
>  3 files changed, 96 insertions(+), 88 deletions(-)
> 
> diff --git a/drivers/media/platform/vimc/vimc-capture.c b/drivers/media/platform/vimc/vimc-capture.c
> index 602f80323031..924b99f82123 100644
> --- a/drivers/media/platform/vimc/vimc-capture.c
> +++ b/drivers/media/platform/vimc/vimc-capture.c
> @@ -321,8 +321,84 @@ static const struct vb2_ops vimc_cap_qops = {
>  	.wait_finish		= vb2_ops_wait_finish,
>  };
>  
> +int vimc_cap_link_validate(struct media_link *link)

This function is only used inside the capture, it could be static.

Unless if you want to make it a generic function in vimc-common.h, so the future
output device could use it as well, but it can be done in the output patch.


> +{
> +	struct v4l2_pix_format source_fmt, sink_fmt;
> +	int ret;
> +
> +	ret = vimc_get_pix_format(link->source, &source_fmt);
> +	if (ret)
> +		return ret;
> +
> +	ret = vimc_get_pix_format(link->sink, &sink_fmt);
> +	if (ret)
> +		return ret;
> +
> +	pr_info("vimc link validate: "
> +		"%s:src:%dx%d (0x%x, %d, %d, %d, %d) "
> +		"%s:snk:%dx%d (0x%x, %d, %d, %d, %d)\n",
> +		/* src */
> +		link->source->entity->name,
> +		source_fmt.width, source_fmt.height,
> +		source_fmt.pixelformat, source_fmt.colorspace,
> +		source_fmt.quantization, source_fmt.xfer_func,
> +		source_fmt.ycbcr_enc,
> +		/* sink */
> +		link->sink->entity->name,
> +		sink_fmt.width, sink_fmt.height,
> +		sink_fmt.pixelformat, sink_fmt.colorspace,
> +		sink_fmt.quantization, sink_fmt.xfer_func,
> +		sink_fmt.ycbcr_enc);
> +
> +	/* The width, height and pixelformat must match. */
> +	if (source_fmt.width != sink_fmt.width
> +	    || source_fmt.height != sink_fmt.height
> +	    || source_fmt.pixelformat != sink_fmt.pixelformat)
> +		return -EPIPE;
> +
> +	/*
> +	 * The field order must match, or the sink field order must be NONE
> +	 * to support interlaced hardware connected to bridges that support
> +	 * progressive formats only.
> +	 */
> +	if (source_fmt.field != sink_fmt.field &&
> +	    sink_fmt.field != V4L2_FIELD_NONE)
> +		return -EPIPE;
> +
> +	/*
> +	 * If colorspace is DEFAULT, then assume all the colorimetry is also
> +	 * DEFAULT, return 0 to skip comparing the other colorimetry parameters
> +	 */
> +	if (source_fmt.colorspace == V4L2_COLORSPACE_DEFAULT
> +	    || sink_fmt.colorspace == V4L2_COLORSPACE_DEFAULT)
> +		return 0;
> +
> +	/* Colorspace must match. */
> +	if (source_fmt.colorspace != sink_fmt.colorspace)
> +		return -EPIPE;
> +
> +	/* Colorimetry must match if they are not set to DEFAULT */
> +	if (source_fmt.ycbcr_enc != V4L2_YCBCR_ENC_DEFAULT
> +	    && sink_fmt.ycbcr_enc != V4L2_YCBCR_ENC_DEFAULT
> +	    && source_fmt.ycbcr_enc != sink_fmt.ycbcr_enc)
> +		return -EPIPE;
> +
> +	if (source_fmt.quantization != V4L2_QUANTIZATION_DEFAULT
> +	    && sink_fmt.quantization != V4L2_QUANTIZATION_DEFAULT
> +	    && source_fmt.quantization != sink_fmt.quantization)
> +		return -EPIPE;
> +
> +	if (source_fmt.xfer_func != V4L2_XFER_FUNC_DEFAULT
> +	    && sink_fmt.xfer_func != V4L2_XFER_FUNC_DEFAULT
> +	    && source_fmt.xfer_func != sink_fmt.xfer_func)
> +		return -EPIPE;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(vimc_cap_link_validate);

No need to export it here.

> +
>  static const struct media_entity_operations vimc_cap_mops = {
> -	.link_validate		= vimc_link_validate,
> +	.link_validate		= vimc_cap_link_validate,
>  };
>  
>  static void vimc_cap_release(struct video_device *vdev)
> diff --git a/drivers/media/platform/vimc/vimc-common.c b/drivers/media/platform/vimc/vimc-common.c
> index a3120f4f7a90..fe91d67811e5 100644
> --- a/drivers/media/platform/vimc/vimc-common.c
> +++ b/drivers/media/platform/vimc/vimc-common.c
> @@ -247,35 +247,40 @@ int vimc_pipeline_s_stream(struct media_entity *ent, int enable)
>  }
>  EXPORT_SYMBOL_GPL(vimc_pipeline_s_stream);
>  
> -static int vimc_get_mbus_format(struct media_pad *pad,
> -				struct v4l2_subdev_format *fmt)
> +int vimc_get_pix_format(struct media_pad *pad,
> +				struct v4l2_pix_format *fmt)

Could you align the arguments please?

>  {
>  	if (is_media_entity_v4l2_subdev(pad->entity)) {
>  		struct v4l2_subdev *sd =
>  			media_entity_to_v4l2_subdev(pad->entity);
> +		struct v4l2_subdev_format sd_fmt;
> +		const struct vimc_pix_map *pix_map;
>  		int ret;
>  
> -		fmt->which = V4L2_SUBDEV_FORMAT_ACTIVE;
> -		fmt->pad = pad->index;
> +		sd_fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> +		sd_fmt.pad = pad->index;
> +
> +		ret = v4l2_subdev_call(sd, pad, get_fmt, NULL, &sd_fmt);
>  

Please remove this blank line, so that the error check follows the function.

> -		ret = v4l2_subdev_call(sd, pad, get_fmt, NULL, fmt);
>  		if (ret)
>  			return ret;
>  
> +		v4l2_fill_pix_format(fmt, &sd_fmt.format);
> +

No need for this blank line.

> +		pix_map = vimc_pix_map_by_code(sd_fmt.format.code);
> +		fmt->pixelformat = pix_map->pixelformat;
> +

Could you also remove this blank like?

>  	} else if (is_media_entity_v4l2_video_device(pad->entity)) {
>  		struct video_device *vdev = container_of(pad->entity,
>  							 struct video_device,
>  							 entity);
>  		struct vimc_ent_device *ved = video_get_drvdata(vdev);
> -		const struct vimc_pix_map *vpix;
> -		struct v4l2_pix_format vdev_fmt;
>  
>  		if (!ved->vdev_get_format)
>  			return -ENOIOCTLCMD;
>  
> -		ved->vdev_get_format(ved, &vdev_fmt);
> -		vpix = vimc_pix_map_by_pixelformat(vdev_fmt.pixelformat);
> -		v4l2_fill_mbus_format(&fmt->format, &vdev_fmt, vpix->code);
> +		ved->vdev_get_format(ved, fmt);
> +

And this one too.

>  	} else {
>  		return -EINVAL;
>  	}
> @@ -283,84 +288,8 @@ static int vimc_get_mbus_format(struct media_pad *pad,
>  	return 0;
>  }
>  
> -int vimc_link_validate(struct media_link *link)
> -{
> -	struct v4l2_subdev_format source_fmt, sink_fmt;
> -	int ret;
> -
> -	ret = vimc_get_mbus_format(link->source, &source_fmt);
> -	if (ret)
> -		return ret;
> -
> -	ret = vimc_get_mbus_format(link->sink, &sink_fmt);
> -	if (ret)
> -		return ret;
> -
> -	pr_info("vimc link validate: "
> -		"%s:src:%dx%d (0x%x, %d, %d, %d, %d) "
> -		"%s:snk:%dx%d (0x%x, %d, %d, %d, %d)\n",
> -		/* src */
> -		link->source->entity->name,
> -		source_fmt.format.width, source_fmt.format.height,
> -		source_fmt.format.code, source_fmt.format.colorspace,
> -		source_fmt.format.quantization, source_fmt.format.xfer_func,
> -		source_fmt.format.ycbcr_enc,
> -		/* sink */
> -		link->sink->entity->name,
> -		sink_fmt.format.width, sink_fmt.format.height,
> -		sink_fmt.format.code, sink_fmt.format.colorspace,
> -		sink_fmt.format.quantization, sink_fmt.format.xfer_func,
> -		sink_fmt.format.ycbcr_enc);
> -
> -	/* The width, height and code must match. */
> -	if (source_fmt.format.width != sink_fmt.format.width
> -	    || source_fmt.format.height != sink_fmt.format.height
> -	    || source_fmt.format.code != sink_fmt.format.code)
> -		return -EPIPE;
> -
> -	/*
> -	 * The field order must match, or the sink field order must be NONE
> -	 * to support interlaced hardware connected to bridges that support
> -	 * progressive formats only.
> -	 */
> -	if (source_fmt.format.field != sink_fmt.format.field &&
> -	    sink_fmt.format.field != V4L2_FIELD_NONE)
> -		return -EPIPE;
> -
> -	/*
> -	 * If colorspace is DEFAULT, then assume all the colorimetry is also
> -	 * DEFAULT, return 0 to skip comparing the other colorimetry parameters
> -	 */
> -	if (source_fmt.format.colorspace == V4L2_COLORSPACE_DEFAULT
> -	    || sink_fmt.format.colorspace == V4L2_COLORSPACE_DEFAULT)
> -		return 0;
> -
> -	/* Colorspace must match. */
> -	if (source_fmt.format.colorspace != sink_fmt.format.colorspace)
> -		return -EPIPE;
> -
> -	/* Colorimetry must match if they are not set to DEFAULT */
> -	if (source_fmt.format.ycbcr_enc != V4L2_YCBCR_ENC_DEFAULT
> -	    && sink_fmt.format.ycbcr_enc != V4L2_YCBCR_ENC_DEFAULT
> -	    && source_fmt.format.ycbcr_enc != sink_fmt.format.ycbcr_enc)
> -		return -EPIPE;
> -
> -	if (source_fmt.format.quantization != V4L2_QUANTIZATION_DEFAULT
> -	    && sink_fmt.format.quantization != V4L2_QUANTIZATION_DEFAULT
> -	    && source_fmt.format.quantization != sink_fmt.format.quantization)
> -		return -EPIPE;
> -
> -	if (source_fmt.format.xfer_func != V4L2_XFER_FUNC_DEFAULT
> -	    && sink_fmt.format.xfer_func != V4L2_XFER_FUNC_DEFAULT
> -	    && source_fmt.format.xfer_func != sink_fmt.format.xfer_func)
> -		return -EPIPE;
> -
> -	return 0;
> -}
> -EXPORT_SYMBOL_GPL(vimc_link_validate);
> -
>  static const struct media_entity_operations vimc_ent_sd_mops = {
> -	.link_validate = vimc_link_validate,
> +	.link_validate = v4l2_subdev_link_validate,
>  };
>  
>  int vimc_ent_sd_register(struct vimc_ent_device *ved,
> diff --git a/drivers/media/platform/vimc/vimc-common.h b/drivers/media/platform/vimc/vimc-common.h
> index 698db7c07645..8a4310430292 100644
> --- a/drivers/media/platform/vimc/vimc-common.h
> +++ b/drivers/media/platform/vimc/vimc-common.h
> @@ -263,6 +263,9 @@ int vimc_ent_sd_register(struct vimc_ent_device *ved,
>  void vimc_ent_sd_unregister(struct vimc_ent_device *ved,
>  			    struct v4l2_subdev *sd);
>  
> +
> +int vimc_get_pix_format(struct media_pad *pad, struct v4l2_pix_format *fmt);
> +

You don't need this if you make the function static.

>  /**
>   * vimc_link_validate - validates a media link
>   *
> 


Thanks!
Helen