Re: [PATCH 00/12] Add TH1520 USB support

[Drew Fustini <fustini@kernel.org>]

On Tue, Jun 09, 2026 at 01:10:41PM +0800, Icenowy Zheng wrote:
> 在 2026-06-08一的 21:17 -0700，Drew Fustini写道：
> > On Thu, May 07, 2026 at 04:16:58PM +0800, Icenowy Zheng wrote:
> > > This patchset adds support for T-Head TH1520's USB functionality,
> > > and
> > > enabled it on the Lichee Pi 4A board.
> > > 
> > > The first 3 patches add support for the MISC subsystem clock
> > > contrtoller, which contains some USB clocks.
> > > 
> > > The next 2 patches add support for the USB PHY of T-Head TH1520,
> > > which
> > > is a wrapped Synopsys USB3.0 FemtoPHY with a little integration
> > > quirk;
> > > the controller itself is a properly configured DWC3 controller with
> > > sane
> > > default register values set.
> > > 
> > > Then one patch adds the USB PHY and controller nodes to the TH1520
> > > DTSI
> > > file.
> > > 
> > > The remaining half of this patchset dedicates to enablement of USB
> > > on
> > > TH1520, because of the onboard hub of that board -- its USB2
> > > signals are
> > > behind a switch that needs to be toggled on, and Vbus supplies for
> > > both
> > > the hub itself and downstream ports are managed via I2C-expanded
> > > GPIOs
> > > (because the SoC does not have enough GPIO pins).
> > 
> > Hi, thanks for working on USB. I tried to apply it to next-20260601
> > and
> > several of the dts patches no longer apply cleanly. Could you rebase?
> 
> I think the reason is that one of the GPIO expansion chip is added to
> the DT for enabling Wi-Fi.

Yeah, I tried to resolve the conflicts but I'm not sure what the correct
resolution is.

a20241c08385 ("riscv: dts: thead: Enable WiFi on Lichee Pi 4A") adds
'clock-frquency = <400000>' to &i2c1 while this series instead sets
'clock-frequency = <100000>'. That commit also sets i2c1_pins
'bias-pull-up = <2100>' while this series sets bias-disable.

> I am not sure whether the next revision of this patchset will contain
> all things, maybe I will split out at least the USB PHY part.

I think splitting out would work, too.

Thanks,
Drew