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 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 = <®_usb>; }; usbphy1: usb-phy@1 { reg = <1>; compatible = "usb-nop-xceiv"; #phy-cells = <0>; + vcc-supply = <®_usb>; }; }; }; -- 2.20.1