Cyclone V: how to enable USB1 with a ULPI USB PHY (USB3320)?

dpeng — Wed, 21 Jan 2026 17:18:49 GMT

I want to enable USB1 (USB 2.0 controller) of the Cyclone V in host-only mode. But Vbus is not present and no device is detected.

A ULPI-compatible Microchip USB3320 USB PHY is connected to the Cyclone V with a ULPI interface. The CPEN pin of the USB3320 controls a power switch on the board. To enable the 5V Vbus voltage, used to power USB devices, the CPEN pin must be driven high. Its POR state is low.
HPS_GPIO0 is connected to the active-low RESET# pin of the USB3320.
To check if Vbus is on, I connected a mouse, that should light up when connected to a USB host.

The main DT file is socfpga.dtsi. I altered it a little in both Barebox and Linux v6.6.22:

&usbphy0 { reset-gpios = <&porta 0 GPIO_ACTIVE_LOW>; status = "okay"; }; &usb1 { status = "okay"; dr_mode = "host"; };

Barebox shows that GPIO0 (RESET#) is an output and is high, which is OK:

barebox:/ gpioinfo ff708000.gpio@ff708000:gpio-controller@0.of GPIOs 454-482, chip ff708000.gpio@ff708000:gpio-controller@0.of: dir val requested name label GPIO 0: out hi active low soc:usbphy.of reset GPIO 1: in lo false GPIO 2: in lo false

Barebox shows that the dwc2 driver binds to usb1:

barebox@Enclustra Mercury+ SA2:/ drvinfo dwc2 Driver Device(s) -------------------- dwc2 ffb40000.usb@ffb40000.of

Linux boot log:

# dmesg | grep -Ei 'usb|dwc2' [ 0.042372] usbcore: registered new interface driver usbfs [ 0.042408] usbcore: registered new interface driver hub [ 0.042448] usbcore: registered new device driver usb [ 0.896138] usbcore: registered new interface driver usb-storage [ 0.920377] usbcore: registered new interface driver usbhid [ 0.932106] usbhid: USB HID core driver [ 1.086689] usb_phy_generic soc:usbphy: dummy supplies not allowed for exclusive requests [ 1.095129] dwc2 ffb40000.usb: supply vusb_d not found, using dummy regulator [ 1.111913] dwc2 ffb40000.usb: supply vusb_a not found, using dummy regulator [ 1.137639] dwc2 ffb40000.usb: DWC OTG Controller [ 1.142362] dwc2 ffb40000.usb: new USB bus registered, assigned bus number 1 [ 1.149465] dwc2 ffb40000.usb: irq 48, io mem 0xffb40000 [ 1.155604] hub 1-0:1.0: USB hub found

I was told that the "dummy regulator" messages are nothing to worry about.

More Linux commands:

# lsusb Bus 001 Device 001: ID 1d6b:0002 Linux 6.6.22 dwc2_hsotg DWC OTG Controller # gpioinfo gpiochip0 gpiochip0 - 29 lines: line 0: unnamed "reset" output active-low [used] line 1: unnamed unused input active-high line 2: unnamed unused input active-high

Re: Cyclone V: how to enable USB1 with a ULPI USB PHY (USB3320)?

Diego_INTEL — Thu, 22 Jan 2026 19:35:07 GMT

Hello @dpeng,

Thank you for contacting Intel Embedded Community.

Please check the following regarding FPGA:

FPGA community forums and blogs have moved to the Altera Community. Existing Intel Community members can sign in with their current credentials.

Best regards,

@Diego_INTEL

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Cyclone V: how to enable USB1 with a ULPI USB PHY (USB3320)?

Re: Cyclone V: how to enable USB1 with a ULPI USB PHY (USB3320)?