Re: [PATCH 0/7] phy: rockchip: usbdp: Fixes, DP 1-lane support and cleanups

From: Sebastian Reichel <sebastian.reichel@collabora.com>
To: Andy Yan <andyshrk@163.com>
Cc: Vinod Koul <vkoul@kernel.org>,
	 Neil Armstrong <neil.armstrong@linaro.org>,
	Heiko Stuebner <heiko@sntech.de>,
	 Andy Yan <andy.yan@rock-chips.com>,
	Yubing Zhang <yubing.zhang@rock-chips.com>,
	 linux-phy@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org,
	 linux-rockchip@lists.infradead.org,
	linux-kernel@vger.kernel.org, kernel@collabora.com,
	 Frank Wang <frank.wang@rock-chips.com>,
	William Wu <william.wu@rock-chips.com>
Subject: Re: [PATCH 0/7] phy: rockchip: usbdp: Fixes, DP 1-lane support and cleanups
Date: Fri, 13 Feb 2026 15:37:06 +0100	[thread overview]
Message-ID: <aY82Lv1rth6fiTJE@venus> (raw)
In-Reply-To: <4a7a30c4.8848.19c288ea1f3.Coremail.andyshrk@163.com>

[-- Attachment #1.1: Type: text/plain, Size: 2208 bytes --]

Hi,

On Wed, Feb 04, 2026 at 08:09:22PM +0800, Andy Yan wrote:
> Hello Sebastian，
> 
> At 2026-02-04 02:41:26, "Sebastian Reichel" <sebastian.reichel@collabora.com> wrote:
> >As there are some issues with the DisplayPort support, I went
> >though Rockchip's BSP kernel tree and looked for fixes. I found
> >two small changes for the initial register setup, which do not
> >help with the DP issue but seem sensible in general. Afterwards
> >I added one more fix, which corrects an issue that effectively
> >results in USB-C adapters with combined USB3+DP capabilities
> >not being able to use the DP part.
> >
> >Afterwards I added one more patch adding single-lane DP support
> >(found in Rockchip BSP kernel) and a couple of cleanups from my
> >side. These are logically independent from the fixes, but I put
> >all together in a single series because they need to be applied
> >in the right order to avoid conflicts.
> >
> >Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
> >---
> >Frank Wang (1):
> >      phy: rockchip: usbdp: Amend SSC modulation deviation
> >
> >Sebastian Reichel (4):
> >      phy: rockchip: usbdp: Add missing mode_change update
> >      phy: rockchip: usbdp: Rename DP lane functions
> >      phy: rockchip: usbdp: Use FIELD_PREP_WM16_CONST
> >      phy: rockchip: usbdp: Cleanup DP lane selection function
> >
> >William Wu (1):
> >      phy: rockchip: usbdp: Fix LFPS detect threshold control
> >
> >Zhang Yubing (1):
> >      phy: rockchip: usbdp: Support single-lane DP
> >
> > drivers/phy/rockchip/phy-rockchip-usbdp.c | 114 +++++++++++++-----------------
> > 1 file changed, 48 insertions(+), 66 deletions(-)
> 
> After applying this series of patches, the hub that previously
> couldn’t recognize Alt Mode can now detect it and work properly,
> but it also triggers a USB-related SERR — did I miss something？

I thought this was from a different patch that I needed to get DP
working. I've spent the last week debugging this and I'm just about
to send v2 with a workaround. FWIW the SError is not introduced by
this series, but before it was much harder to run into it.

Greetings,

-- Sebastian

[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

[-- Attachment #2: Type: text/plain, Size: 112 bytes --]

-- 
linux-phy mailing list
linux-phy@lists.infradead.org
https://lists.infradead.org/mailman/listinfo/linux-phy