Re: [PATCH v13 17/22] media: i2c: maxim-serdes: add MAX96724 driver

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] max96724_phy_id() unconditionally aliases disabled PHY 1 to hardware PHY 0, causing TPG routing to corrupt active video on MAX96712.
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commit 7c9381a0fe7a58d01cf134ab630461bdeb994484
Author: Cosmin Tanislav <demonsingur@gmail.com>

media: i2c: maxim-serdes: add MAX96724 driver

Add a new MAX96724 driver that also supports MAX96712, MAX96724F
and MAX96724R, integrating it with the common deserializer framework.

> diff --git a/drivers/media/i2c/maxim-serdes/max96724.c b/drivers/media/i2c/maxim-serdes/max96724.c
> new file mode 100644
> index 0000000000000..7fc51254e1ef4
> --- /dev/null
> +++ b/drivers/media/i2c/maxim-serdes/max96724.c
[ ... ]
> +static unsigned int max96724_phy_id(struct max_des *des, struct max_des_phy *phy)
> +{
> +	unsigned int num_hw_data_lanes = max_des_phy_hw_data_lanes(des, phy);
> +
> +	/* PHY 1 is the master PHY when combining PHY 0 and PHY 1. */
> +	if (phy->index == 0 && num_hw_data_lanes == 4)
> +		return 1;
> +
> +	if (phy->index == 1 && !des->phys[1].enabled)
> +		return 0;

[Severity: High]
Could this unconditional aliasing of disabled PHY 1 to hardware PHY 0 cause
test pattern generator (TPG) routing to corrupt active video on MAX96712?

If PHY 0 is operating in a standard 2-lane configuration and actively
streaming real video, and PHY 1 is disabled, this returns 0 without
verifying if PHY 0 is actually configured in a 4-lane mode.

On MAX96712, set_pipe_phy is not supported. When the TPG is enabled, dummy
remaps are set up for unused pipes to discard the globally injected TPG data,
routing them to an unused PHY (e.g., PHY 1). If max96724_set_pipe_remap()
evaluates the hardware ID for this unused PHY using max96724_phy_id(), it
gets hardware ID 0 instead of 1.

Will this cause the hardware to route the unmapped TPG data directly into
PHY 0 and corrupt the active video output stream?

> +
> +	return phy->index;
> +}
[ ... ]

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Sashiko AI review · https://sashiko.dev/#/patchset/20260604-gmsl2-3_serdes-v13-0-9d8a4919983b@analog.com?part=17