RE: [PATCH 3/4] arm64: dts: imx8mp: Add snps, gfladj-refclk-lpm-sel quirk to USB nodes

[Alexander Stein <alexander.stein@ew.tq-group.com>]

Am Donnerstag, 8. September 2022, 11:12:23 CEST schrieb Jun Li:
> > -----Original Message-----
> > From: Alexander Stein <alexander.stein@ew.tq-group.com>
> > Sent: Wednesday, September 7, 2022 10:46 PM
> > To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>; Rob Herring
> > <robh+dt@kernel.org>; Krzysztof Kozlowski
> > <krzysztof.kozlowski+dt@linaro.org>; Shawn Guo <shawnguo@kernel.org>;
> > Sascha Hauer <s.hauer@pengutronix.de>; Pengutronix Kernel Team
> > <kernel@pengutronix.de>; Fabio Estevam <festevam@gmail.com>; dl-linux-imx
> > <linux-imx@nxp.com>; Jun Li <jun.li@nxp.com>
> > Cc: Alexander Stein <alexander.stein@ew.tq-group.com>;
> > linux-usb@vger.kernel.org; devicetree@vger.kernel.org;
> > linux-kernel@vger.kernel.org
> > Subject: [PATCH 3/4] arm64: dts: imx8mp: Add snps,gfladj-refclk-lpm-sel
> > quirk to USB nodes
> > 
> > With this set the SOF/ITP counter is based on ref_clk when 2.0 ports are
> > suspended.
> > 
> > Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> > ---
> > 
> >  arch/arm64/boot/dts/freescale/imx8mp.dtsi | 2 ++
> >  1 file changed, 2 insertions(+)
> > 
> > diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> > b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> > index 53493dc7d976..0e7f5842a3e4 100644
> > --- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> > +++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> > @@ -1300,6 +1300,7 @@ usb_dwc3_0: usb@38100000 {
> > 
> >  				phys = <&usb3_phy0>, <&usb3_phy0>;
> >  				phy-names = "usb2-phy", "usb3-
phy";
> >  				snps,dis-u2-freeclk-exists-quirk;
> 
> So this property can be removed?

I'm not so sure about this one, as the description is talking about USB2 PHY 
providing a free-running PHY clock. I don't know the details if this is true 
or not.
But removing snps,dis-u2-freeclk-exists-quirk from both USB device nodes, USB 
devices attachments are still detected when the USB hub is suspended, both 
super-speed and high-speed ports.

Best regards,
Alexander

> > +				snps,gfladj-refclk-lpm-sel-quirk;
> > 
> >  			};
> >  		
> >  		};
> > 
> > @@ -1342,6 +1343,7 @@ usb_dwc3_1: usb@38200000 {
> > 
> >  				phys = <&usb3_phy1>, <&usb3_phy1>;
> >  				phy-names = "usb2-phy", "usb3-
phy";
> >  				snps,dis-u2-freeclk-exists-quirk;
> 
> Ditto.
> 
> Li Jun
> 
> > +				snps,gfladj-refclk-lpm-sel-quirk;
> > 
> >  			};
> >  		
> >  		};
> > 
> > --
> > 2.25.1