Re: [PATCH v2 2/5] arm64: dts: rockchip: Enable USB 2.0 ports on Radxa E20C

From: Heiko Stuebner <heiko@sntech.de>
To: Chukun Pan <amadeus@jmu.edu.cn>
Cc: jonas@kwiboo.se, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-rockchip@lists.infradead.org,
	Chukun Pan <amadeus@jmu.edu.cn>
Subject: Re: [PATCH v2 2/5] arm64: dts: rockchip: Enable USB 2.0 ports on Radxa E20C
Date: Thu, 28 May 2026 07:57:45 +0200	[thread overview]
Message-ID: <3879225.zToM8qfIzz@phil> (raw)
In-Reply-To: <20260525065005.1056845-1-amadeus@jmu.edu.cn>

Hi,

Am Montag, 25. Mai 2026, 08:50:05 Mitteleuropäische Sommerzeit schrieb Chukun Pan:
> > +&usb_host0_xhci {
> > +	extcon = <&usb2phy>;
> > +	maximum-speed = "high-speed";
> > +	phys = <&usb2phy_otg>;
> > +	phy-names = "usb2-phy";
> 
> I received this warning for this otg port:
> [    0.163307] dwc3 fe500000.usb: Configuration mismatch. dr_mode forced to host

Interesting, because if I read the schematics correctly, this is the
controller labeled "usb2.0 otg0" .
It even has a vbus-detect line.

If I understand the schematics and product page correctly, this
actually is an outward facing type-c-port, making the device a
peripheral?

usb_host0_xhci -> port1 of FE1.1s_QFN (device1 connected to the hub)
uart0 -> ch340 -> port2 of FE1.1s_QFN (device2 connected to the hub)

FE1.1s_QFN host dm+dp going to the type-c port of the board.

So if anything, that controller should probably have dr_mode=peripheral
I think?

> 
> > +	snps,dis_u2_susphy_quirk;
> 
> This property is missing in the sige1 patch. Since this property
> is related to phy vbus detection, can we move it to rk3528.dtsi?

yeah, that sounds sensible ... looking at the other socs using that
quirk, it really seems to be a property of the controller.

Heiko