Re: [PATCH v10 13/36] phy: rockchip: usbdp: Rename DP lane functions

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] Failure during PHY initialization destroys active PHY hardware state while leaving software state out of sync.
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commit 27edcd7e836a7f62ad5d0b336e4f8cfd4fedc67c
Author: Sebastian Reichel <sebastian.reichel@collabora.com>

phy: rockchip: usbdp: Rename DP lane functions

The patch updates the two DisplayPort lane functions to follow the common
rk_udphy_dp_ prefix scheme for consistency.

> diff --git a/drivers/phy/rockchip/phy-rockchip-usbdp.c b/drivers/phy/rockchip/phy-rockchip-usbdp.c
> index b172ce6a722ee..7fb864a1486c0 100644
> --- a/drivers/phy/rockchip/phy-rockchip-usbdp.c
> +++ b/drivers/phy/rockchip/phy-rockchip-usbdp.c
[ ... ]
> @@ -1069,7 +1069,7 @@ static int rk_udphy_dp_phy_power_off(struct phy *phy)
>  	struct rk_udphy *udphy = phy_get_drvdata(phy);
>  
>  	mutex_lock(&udphy->mutex);
> -	rk_udphy_dplane_enable(udphy, 0);
> +	rk_udphy_dp_lane_enable(udphy, 0);
>  	rk_udphy_power_off(udphy, UDPHY_MODE_DP);
>  	mutex_unlock(&udphy->mutex);

[Severity: High]
This isn't a bug introduced by this patch, but looking at the driver, does
failure during PHY initialization destroy active PHY hardware state while
leaving the software state out of sync?

If rk_udphy_init() fails during a mode change (e.g., PLL lock timeout when a
DP cable is plugged in), it aborts, asserts all PHY resets, and returns an
error:

drivers/phy/rockchip/phy-rockchip-usbdp.c:rk_udphy_init() {
    ...
assert_resets:
	rk_udphy_reset_assert_all(udphy);
	return ret;
}

When this happens, rk_udphy_update_power_state() receives the error, notifies
DWC3 that the reset is complete, and returns early without clearing
udphy->status:

drivers/phy/rockchip/phy-rockchip-usbdp.c:rk_udphy_update_power_state() {
    ...
		ret = rk_udphy_init(udphy);
		if (ret) {
			phy_notify_reset(udphy->phy_u3, PHY_NOTIFY_POST_RESET);
			return ret;
		}
    ...
}

Will this cause the DWC3 USB controller to access a physically dead (reset)
PHY and crash the system with a synchronous external abort (SError), since
the controller is explicitly told the PHY is ready and the software driver is
left believing it is fully functional?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260703-rockchip-usbdp-cleanup-v10-0-a392711ca8a9@collabora.com?part=13

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