RE: [PATCH] ARM: imx25: provide a fixed regulator for usb phys

[Peter Chen <peter.chen@xxxxxxx>]

> On 19-06-26 02:40, Peter Chen wrote:
> >
> > > Subject: [PATCH] ARM: imx25: provide a fixed regulator for usb phys
> > >
> > > The usb phys are internal to the SoC and so it their 5V supply. With
> > > this regulator added explicitly the following (harmless) boot messages go away:
> > >
> > > 	usb_phy_generic usbphy:usb-phy@0: usbphy:usb-phy@0 supply vcc not
> > > found, using dummy regulator
> > > 	usb_phy_generic usbphy:usb-phy@1: usbphy:usb-phy@1 supply vcc not
> > > found, using dummy regulator
> > >
> >
> > To eliminate the warning message, I suggest doing below changes, as
> > vcc supply is not mandatory.
> >
> > diff --git a/drivers/usb/phy/phy-generic.c
> > b/drivers/usb/phy/phy-generic.c index a53b89be5324..01a5ff1a0515
> > 100644
> > --- a/drivers/usb/phy/phy-generic.c
> > +++ b/drivers/usb/phy/phy-generic.c
> > @@ -275,7 +275,7 @@ int usb_phy_gen_create_phy(struct device *dev, struct
> usb_phy_generic *nop,
> >                 }
> >         }
> >
> > -       nop->vcc = devm_regulator_get(dev, "vcc");
> > +       nop->vcc = devm_regulator_get_optional(dev, "vcc");
> 
> Is the regulator optional? IMHO this shouldn't be the fix. I think the right fix is Uwe's
> approach.
> 

Add Felipe.

Some USB PHY's power are from the core system's power (eg, DDR), and some are
fixed at the board and no switch for it. So, it is transparent for software at some cases.

Peter

> Regards,
>   Marco
> 
> >         if (IS_ERR(nop->vcc)) {
> >                 dev_dbg(dev, "Error getting vcc regulator: %ld\n",
> >                                         PTR_ERR(nop->vcc));
> >
> > Peter
> >
> > > Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
> > > ---
> > > Hello,
> > >
> > > note I'm an USB noob, so please consider carefully before applying
> > > :-) I also put the regulator near the usbphy node instead of in
> > > alphabetic order. Not sure what is sensible/usual here, too.
> > >
> > > Best regards
> > > Uwe
> > >
> > >  arch/arm/boot/dts/imx25.dtsi | 9 +++++++++
> > >  1 file changed, 9 insertions(+)
> > >
> > > diff --git a/arch/arm/boot/dts/imx25.dtsi
> > > b/arch/arm/boot/dts/imx25.dtsi
> > > --- a/arch/arm/boot/dts/imx25.dtsi
> > > +++ b/arch/arm/boot/dts/imx25.dtsi
> > > @@ -614,6 +614,11 @@
> > >  		};
> > >  	};
> > >
> > > +	reg_usb: regulator_usbphy {
> > > +		compatible = "regulator-fixed";
> > > +		regulator-name = "usb-phy supply";
> > > +	};
> > > +
> > >  	usbphy {
> > >  		compatible = "simple-bus";
> > >  		#address-cells = <1>;
> > > @@ -623,12 +630,14 @@
> > >  			reg = <0>;
> > >  			compatible = "usb-nop-xceiv";
> > >  			#phy-cells = <0>;
> > > +			vcc-supply = <&reg_usb>;
> > >  		};
> > >
> > >  		usbphy1: usb-phy@1 {
> > >  			reg = <1>;
> > >  			compatible = "usb-nop-xceiv";
> > >  			#phy-cells = <0>;
> > > +			vcc-supply = <&reg_usb>;
> > >  		};
> > >  	};
> > >  };
> > > --
> > > 2.20.1
> >
> 
> --
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