Re: [PATCH] staging: media: starfive: Add multiple resolution support

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Changhuang,

Thank you for the patch.

On Fri, Apr 19, 2024 at 01:19:55AM -0700, Changhuang Liang wrote:
> Add multiple resolution support for video "capture_raw" device. Otherwise
> it will capture the wrong image data if the width is not 1920.
> 
> Fixes: e080f339c80a ("media: staging: media: starfive: camss: Add capture driver")
> 
> Signed-off-by: Changhuang Liang <changhuang.liang@starfivetech.com>
> ---
>  drivers/staging/media/starfive/camss/stf-capture.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/media/starfive/camss/stf-capture.c b/drivers/staging/media/starfive/camss/stf-capture.c
> index ec5169e7b391..9e853ff2596a 100644
> --- a/drivers/staging/media/starfive/camss/stf-capture.c
> +++ b/drivers/staging/media/starfive/camss/stf-capture.c
> @@ -177,9 +177,12 @@ static void stf_channel_set(struct stfcamss_video *video)
>  {
>  	struct stf_capture *cap = to_stf_capture(video);
>  	struct stfcamss *stfcamss = cap->video.stfcamss;
> +	struct v4l2_pix_format *pix;

This variable can be const as you don't modify the format.

>  	u32 val;
> 
>  	if (cap->type == STF_CAPTURE_RAW) {
> +		pix = &video->active_fmt.fmt.pix;

And it can be declared and initialized here:

		const struct v4l2_pix_format *pix = &video->active_fmt.fmt.pix;

> +
>  		val = stf_syscon_reg_read(stfcamss, VIN_CHANNEL_SEL_EN);
>  		val &= ~U0_VIN_CHANNEL_SEL_MASK;
>  		val |= CHANNEL(0);
> @@ -193,7 +196,7 @@ static void stf_channel_set(struct stfcamss_video *video)
>  		val |= PIXEL_HEIGH_BIT_SEL(0);
> 
>  		val &= ~U0_VIN_PIX_CNT_END_MASK;
> -		val |= PIX_CNT_END(IMAGE_MAX_WIDTH / 4 - 1);
> +		val |= PIX_CNT_END(pix->width / 4 - 1);

Is there no need to consider the image height as well ? How does the
driver prevent buffer overflows if the sensor sends more data than
expected ?

> 
>  		stf_syscon_reg_write(stfcamss, VIN_INRT_PIX_CFG, val);
>  	} else if (cap->type == STF_CAPTURE_YUV) {

-- 
Regards,

Laurent Pinchart