Re: [PATCH v8 20/29] phy: rockchip: usbdp: Re-init the PHY on orientation change

[sashiko-bot@kernel.org]

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

Pre-existing issues:
- [High] Hardware lane muxing is never actively updated for USB-only devices upon replug or orientation change, breaking USB SuperSpeed in reverse orientation on ports that do not power-cycle the PHY.
--

commit 52b656ef41c03fa9932c56f88505027225e05d96
Author: Sebastian Reichel <sebastian.reichel@collabora.com>

phy: rockchip: usbdp: Re-init the PHY on orientation change

This commit updates the driver to record cable orientation changes and set the
phy_needs_reinit flag. It aims to fix DP functionality breaking when the cable
is re-plugged with a swapped orientation.

> diff --git a/drivers/phy/rockchip/phy-rockchip-usbdp.c b/drivers/phy/rockchip/phy-rockchip-usbdp.c
> index 1bb22fc18c9f9..3d222768dc3c9 100644
> --- a/drivers/phy/rockchip/phy-rockchip-usbdp.c
> +++ b/drivers/phy/rockchip/phy-rockchip-usbdp.c
> @@ -626,6 +626,7 @@ static int rk_udphy_orien_sw_set(struct typec_switch_dev *sw,
>  				 enum typec_orientation orien)
>  {
>  	struct rk_udphy *udphy = typec_switch_get_drvdata(sw);
> +	bool flipped = orien == TYPEC_ORIENTATION_REVERSE;
>  
>  	mutex_lock(&udphy->mutex);
>  
> @@ -637,7 +638,10 @@ static int rk_udphy_orien_sw_set(struct typec_switch_dev *sw,
>  		goto unlock_ret;
>  	}
>  
> -	udphy->flip = orien == TYPEC_ORIENTATION_REVERSE;
> +	if (udphy->flip != flipped)
> +		udphy->phy_needs_reinit = true;
> +
> +	udphy->flip = flipped;

[Severity: High]
This is a pre-existing issue, but does this actually flush the re-initialization
to the hardware if the USB PHY is already running?

When a user replugs a USB-only Type-C device in reverse orientation on a port
where the USB controller does not power-cycle the PHY on unplug, for example in
host mode, rk_udphy_orien_sw_set() notes the orientation change and sets
udphy->phy_needs_reinit = true.

However, because the USB controller keeps the PHY powered on,
udphy->status & UDPHY_MODE_USB remains true.

When rk_udphy_typec_mux_set() is called later to handle the mux event, it
appears to skip actively re-initializing the PHY if the USB mode is already
active:

    if ((udphy->mode & UDPHY_MODE_USB) && !(udphy->status & UDPHY_MODE_USB) &&
        udphy->usb_in_use && !udphy->hs)
        return rk_udphy_power_on(udphy, UDPHY_MODE_USB);

    return 0;

Could this leave the hardware stuck in the old orientation state and break USB
SuperSpeed, causing it to fall back to USB 2.0 upon reverse replug?

>  	rk_udphy_set_typec_default_mapping(udphy);
>  	rk_udphy_usb_bvalid_enable(udphy, true);

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260626-rockchip-usbdp-cleanup-v8-0-47f682987895@collabora.com?part=20

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