From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9F102449B12; Tue, 21 Jul 2026 00:43:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784594634; cv=none; b=dwFdHwnNXtZIqgVOHaEQ2NjmuCUbHvT/dex7cnpfVzTdbZnPo9UgLJPNbfy2+16me2UxZolWSvhnn4zPbAWAhLAB6TWrVjLTn2Gp57ZQIM8lr1KF6vWyH1svoMDlX8wL1BtMSGtV2zYH5Xb2FBctHr4MkkUby+fF1C25CX8hkBA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784594634; c=relaxed/simple; bh=cbUUJ+eotvRm5zqUM2Kx6OHXTRyJBbLTfUabYVaGVJU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=eUM3a/7ivqmgD8ZCMd3ZaT+2T+bOLM+Vrl5UDWx1XxR/+rMlGFDh57QSnDTcpd/hLdwa6JXFaNhSW3TcaPsxQBDj+xemPkfHiZsi3YbYNowm2XURAKjTNTfroSUDFzaNxnjxlRhDMNQk4VSM1VYDXiPG6J6WNvRXPPGnHxp6ZOA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RcUB+xYs; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="RcUB+xYs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 60AA41F000E9; Tue, 21 Jul 2026 00:43:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784594633; bh=Fd7hZsvKd8rP/mpwq0Fu3nIETh38pakepxFmYnJYgxg=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=RcUB+xYsd+/61NPi9gClvOM297EcDNaD3cip6fmFmafrbDFc35548GifLazPnBIE7 72vA+A031otpSAV4CSK+7zxnl39hBheSrMIj7rf28bo3naMhrR8q+QkGuM8jywBGR4 AqpSba3upqKYQrEzeW3hU0sGclvpreircWESkf0H82zqO9yaDa0k9BJn8dotvaK0EI GeiIrJLVP1s7Pa+aqCtPZvpT328JqaMzeFYs3wWz5EkBky1sTrjnNjtssxjeKeIZtX OcUS/+XPTeE0NzhhVj1Di4KN66SZIzu6KY0gNXvf6K/lEvTSuZoaQD4RO2AerjPzXy z7/oXCTWCFw6Q== Received: by venus (Postfix, from userid 1000) id CF0C81804CE; Tue, 21 Jul 2026 02:43:51 +0200 (CEST) Date: Tue, 21 Jul 2026 02:43:51 +0200 From: Sebastian Reichel To: jens.glathe@oldschoolsolutions.biz Cc: Greg Kroah-Hartman , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Abel Vesa , Heikki Krogerus , Bjorn Andersson , Konrad Dybcio , linux-usb@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, stable@vger.kernel.org, "Dr. David Alan Gilbert" Subject: Re: [PATCH 0/5] usb: typec: ps883x: fixes for older Thunderbolt 4 / USB4 docks Message-ID: References: <20260718-ps883x-disable-usb4-v1-0-cec86d0b909e@oldschoolsolutions.biz> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="fkc6jiysmodswgij" Content-Disposition: inline In-Reply-To: <20260718-ps883x-disable-usb4-v1-0-cec86d0b909e@oldschoolsolutions.biz> --fkc6jiysmodswgij Content-Type: text/plain; protected-headers=v1; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH 0/5] usb: typec: ps883x: fixes for older Thunderbolt 4 / USB4 docks MIME-Version: 1.0 Hello, On Sat, Jul 18, 2026 at 07:06:28PM +0200, Jens Glathe via B4 Relay wrote: > On Qualcomm X1E80100 platforms (e.g. Lenovo ThinkPad T14s Gen 6) > using the Parade PS883x retimer, connecting USB4-capable docks such > as the Lenovo 40B0 via a regular Type-C cable (which forces the dock > into Type-C fallback mode) often results in working USB but no > DisplayPort output. >=20 > This series addresses the issue with two main changes: >=20 > - Add a new optional DT property "parade,disable-usb4". When present, > the PS883x driver rejects USB4 mode (-EOPNOTSUPP). This forces the > Type-C stack to fall back to USB3 + DP Alt Mode, which works > reliably with the 40B0. >=20 > - Refactor DP altmode handling to also support the legacy > TYPEC_DP_STATE_F request (deprecated since DP Alt Mode 1.0b) sent by > the 40B0 and other docks (e.g. SSK SC220). >=20 > - Add a short delay after writing configuration registers, which > improves hotplug reliability. >=20 > This is a temporary workaround until full USB4 DP tunneling support is > available in the X1E USB4 controller and qmp-combo PHY stack. >=20 > Note: The DT patch adds the new property to all currently upstream > boards using the PS883x retimer (15 files). Happy to split it on v2 > if requested. I don't think a kernel driver limitation is a good reason for the DT property. I suggest to add something like this in the ps883x driver instead: /* * Hamoa does not yet support USB4, disable it for now to gracefully * fall back to USB3 + DP AltMode. This should be removed once USB4 * support landed for X1E. */ if (of_machine_is_compatible("qcom,x1e80100")) disable_usb4 =3D true; Greetings, -- Sebastian > As an additional observation, the same dock with type-c cable works well > on Thinkpad X13s, Thinkbook 16 G7 QOY, Ideapad 5 14Q8X9, but doesn't need > the ps883x changes (naturally).=20 >=20 > Signed-off-by: Jens Glathe > --- > Jens Glathe (5): > dt-bindings: usb: parade,ps8830: Add parade,disable-usb4 property > usb: typec: ps883x: Return -EOPNOTSUPP for USB4 when parade,disable= -usb4 is set > usb: typec: mux: ps883x: refactor DP altmode handling and support T= YPEC_DP_STATE_F > usb: typec: mux: ps883x: add a delay after writing config regs > arm64: dts: qcom: x1: disable ps883x USB4 capability >=20 > .../devicetree/bindings/usb/parade,ps8830.yaml | 6 +++ > arch/arm64/boot/dts/qcom/hamoa-iot-evk.dts | 4 ++ > .../qcom/hamoa-lenovo-ideacentre-mini-01q8x10.dts | 2 + > arch/arm64/boot/dts/qcom/purwa-iot-evk.dts | 6 +++ > arch/arm64/boot/dts/qcom/x1-asus-vivobook-s15.dtsi | 4 ++ > arch/arm64/boot/dts/qcom/x1-asus-zenbook-a14.dtsi | 4 ++ > arch/arm64/boot/dts/qcom/x1-crd.dtsi | 6 +++ > arch/arm64/boot/dts/qcom/x1-dell-thena.dtsi | 4 ++ > arch/arm64/boot/dts/qcom/x1-hp-omnibook-x14.dtsi | 2 + > arch/arm64/boot/dts/qcom/x1-microsoft-denali.dtsi | 4 ++ > arch/arm64/boot/dts/qcom/x1e001de-devkit.dts | 6 +++ > .../dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi | 4 ++ > .../boot/dts/qcom/x1e80100-dell-xps13-9345.dts | 4 ++ > .../boot/dts/qcom/x1e80100-lenovo-yoga-slim7x.dts | 6 +++ > .../dts/qcom/x1e80100-medion-sprchrgd-14-s1.dts | 2 + > .../boot/dts/qcom/x1e80100-microsoft-romulus.dtsi | 4 ++ > drivers/usb/typec/mux/ps883x.c | 47 +++++++++++++++-= ------ > 17 files changed, 100 insertions(+), 15 deletions(-) > --- > base-commit: 0718283ab28bc3907e10b61a6b4be6fefa1cbb2f > change-id: 20260718-ps883x-disable-usb4-19b0fc13b5ab >=20 > Best regards, > --=20 > Jens Glathe >=20 >=20 >=20 --fkc6jiysmodswgij Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEE72YNB0Y/i3JqeVQT2O7X88g7+poFAmpewMMACgkQ2O7X88g7 +powWBAAol0/PBJ1eXYYjlNiwB7qCbCecEfZTULQrX4zFmaA3o1MaYHhWFBR2WlK L74HXVNCoFn/IDQV0U4qDy15RPrOAr+NLj2sdyr6jqHx54IPi3OBHumGmEWrJmAO EGvtyp/AJb5mt7cvLlOoZukTcqgEP/oKgufLnER4KfHzcemjWMmcspzbOpz3648z 7igV6sjiF0IoxzrzZKhWLKu12UWAPZE6BsrI/J2v3oojgJShxBZPaD+QblK7M4ME /b8tSYxWIVMiHCKQVebR4ZGyjEbMW5FvMYqZ3+H7otYTZu3VniPu8C/XSyohj3fy wxN/lOUOrSeM9uTaQWUjgQIongdBLc5gEoWQCp1U512bKCXkozn1UQThc5raqhoa wbTD/ZMioGLf//hOBk1FT+Gq/O+SEABPcMQ2zmHvHF8Pueeld7QuFU8Pd9dCbY5b /k7VlT/sKkJ0EvRZ6eEtdqCthk855FAvDQPS6Y3cVTfurlobnXPR7saZ7sR8AEne letJqKFPNXGMC5LQA7EdoQxNHU0lmYLeHsTKiDRvI34YluwsRvRH1fR/B7ipB150 /bkqIu+I88a/9DFFBbkcr1+QUYxRdFTFnG5bNew6BqIUQrBA/GeqOOXGQ2BMm4cQ 8l0Mblkqr3Gv3ZoZIx5R784zqBlD/3CwR3SwhU4nOF3Z8z5GMdc= =lVu4 -----END PGP SIGNATURE----- --fkc6jiysmodswgij--