Re: [PATCH v3 5/5] media: imx8-isi: Enable ISI RAW10/12/14 output LSB alignment

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] media: imx8-isi: Unconditional setting of RAW alignment bits may corrupt non-RAW streams
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commit 24f35e10010e44cf9f1ebb2452592fd2a6c1b167
Author: Guoniu Zhou <guoniu.zhou@oss.nxp.com>

media: imx8-isi: Enable ISI RAW10/12/14 output LSB alignment

This commit updates the i.MX8 ISI driver to use the hardware LSB alignment
capability introduced in i.MX952 for RAW10/12/14 formats. It drops the older
RAW16 workaround for these newer platforms and updates the alignment bits
during channel setup.

> diff --git a/drivers/media/platform/nxp/imx8-isi/imx8-isi-hw.c b/drivers/media/platform/nxp/imx8-isi/imx8-isi-hw.c
> index 6aa760ce36053..0832b4a110ed2 100644
> --- a/drivers/media/platform/nxp/imx8-isi/imx8-isi-hw.c
> +++ b/drivers/media/platform/nxp/imx8-isi/imx8-isi-hw.c

[ ... ]

> @@ -357,6 +368,20 @@ static void mxc_isi_channel_set_control(struct mxc_isi_pipe *pipe,
>  			val |= CHNL_CTRL_VC_ID_1(vc >> 2);
>  	}
>  
> +	if (isi_raw_out_lsb(pdata)) {
> +		/*
> +		 * Enable RAW10/12/14 output LSB alignment to match the
> +		 * V4L2 requirement that RAW formats are LSB-aligned.
> +		 */
> +		val |= CHNL_CTRL_RAW_OUT_LSB_ALIGN;
> +
> +		/*
> +		 * Align the data selection from pixel link to MSB to
> +		 * avoid data shift since the data from PL is MSB.
> +		 */
> +		val |= CHNL_CTRL_RAW_IN_MSB_ALIGN;
> +	}
> +

[Severity: Medium]
When starting a non-RAW stream (such as YUV or RGB) on an i.MX952 platform,
could setting these alignment bits unconditionally cause data shift or
corruption for the non-RAW video streams?

It looks like mxc_isi_channel_set_control() applies these bits without
checking if the currently active format is actually a RAW format. Would it
make sense to verify the active stream format before enabling these bits?

>  	mxc_isi_write(pipe, CHNL_CTRL, val);
>  
>  	mutex_unlock(&pipe->lock);

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Sashiko AI review · https://sashiko.dev/#/patchset/20260915-isi_imx952-v3-0-3d8ff1363dda@oss.nxp.com?part=5