Re: [PATCH 3/8] media: imx: Use dedicated format handler for i.MX7/8

[Laurent Pinchart]

Hi Alexander and Dorota,

Thank you for the patch.

On Fri, Feb 04, 2022 at 01:15:09PM +0100, Alexander Stein wrote:
> From: Dorota Czaplejewicz <dorota.czaplejewicz@xxxxxxx>
> 
> This splits out a format handler which takes into account
> the capabilities of the i.MX7/8 video device,
> as opposed to the default handler compatible with both i.MX5/6 and i.MX7/8.
> 
> Signed-off-by: Dorota Czaplejewicz <dorota.czaplejewicz@xxxxxxx>
> Signed-off-by: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>
> ---
> Changes in comparison to original commit from Dorota:
> * is_imx56 is used instead of enum
> 
>  drivers/staging/media/imx/imx-media-utils.c | 56 +++++++++++++++++++--
>  1 file changed, 52 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/staging/media/imx/imx-media-utils.c b/drivers/staging/media/imx/imx-media-utils.c
> index 0daa6aad45f4..32aaa2e81bea 100644
> --- a/drivers/staging/media/imx/imx-media-utils.c
> +++ b/drivers/staging/media/imx/imx-media-utils.c
> @@ -516,10 +516,9 @@ void imx_media_try_colorimetry(struct v4l2_mbus_framefmt *tryfmt,
>  }
>  EXPORT_SYMBOL_GPL(imx_media_try_colorimetry);
>  
> -int imx_media_mbus_fmt_to_pix_fmt(struct v4l2_pix_format *pix,
> -				  const struct v4l2_mbus_framefmt *mbus,
> -				  const struct imx_media_pixfmt *cc,
> -				  bool is_imx56)
> +static int imx56_media_mbus_fmt_to_pix_fmt(struct v4l2_pix_format *pix,
> +					   const struct v4l2_mbus_framefmt *mbus,
> +					   const struct imx_media_pixfmt *cc)
>  {
>  	u32 width;
>  	u32 stride;
> @@ -568,6 +567,55 @@ int imx_media_mbus_fmt_to_pix_fmt(struct v4l2_pix_format *pix,
>  
>  	return 0;
>  }
> +
> +static int imx78_media_mbus_fmt_to_pix_fmt(struct v4l2_pix_format *pix,
> +					   const struct v4l2_mbus_framefmt *mbus,
> +					   const struct imx_media_pixfmt *cc)
> +{
> +	int ret;
> +
> +	if (!cc)
> +		cc = imx_media_find_mbus_format(mbus->code, PIXFMT_SEL_ANY);
> +
> +	if (!cc)
> +		return -EINVAL;
> +	/*
> +	 * The hardware can handle line lengths divisible by 4 pixels
> +	 * as long as the whole buffer size ends up divisible by 8 bytes.
> +	 * If not, use the value of 8 pixels recommended in the datasheet.
> +	 */
> +	ret = v4l2_fill_pixfmt(pix, cc->fourcc,
> +			       round_up(mbus->width, 4), mbus->height);
> +	if (ret)
> +		return ret;
> +
> +	/* Only 8bits-per-pixel formats may need to get aligned to 8 pixels,
> +	 * because both 10-bit and 16-bit pixels occupy 2 bytes.
> +	 * In those, 4-pixel aligmnent is equal to 8-byte alignment.
> +	 */
> +	if (pix->sizeimage % 8 != 0)
> +		ret = v4l2_fill_pixfmt(pix, cc->fourcc,
> +				       round_up(mbus->width, 8), mbus->height);

I think you could simplify this by using cc->bpp to figure out the
alignment instead of calling v4l2_fill_pixfmt() twice.

> +
> +	pix->colorspace = mbus->colorspace;
> +	pix->xfer_func = mbus->xfer_func;
> +	pix->ycbcr_enc = mbus->ycbcr_enc;
> +	pix->quantization = mbus->quantization;
> +	pix->field = mbus->field;

Should v4l2_fill_pixfmt() be updated to handle colorspace and field too
instead of doing it manually here ?

> +
> +	return ret;
> +}
> +
> +int imx_media_mbus_fmt_to_pix_fmt(struct v4l2_pix_format *pix,
> +				  const struct v4l2_mbus_framefmt *mbus,
> +				  const struct imx_media_pixfmt *cc,
> +				  bool is_imx56)
> +{
> +	if (is_imx56)
> +		return imx56_media_mbus_fmt_to_pix_fmt(pix, mbus, cc);
> +	else
> +		return imx78_media_mbus_fmt_to_pix_fmt(pix, mbus, cc);
> +}
>  EXPORT_SYMBOL_GPL(imx_media_mbus_fmt_to_pix_fmt);
>  
>  void imx_media_free_dma_buf(struct device *dev,

-- 
Regards,

Laurent Pinchart