F1C100s: libusb couldn't open device

[ceneblock]

Hello everyone!

  I'm following this design here:

  https://www.thirtythreeforty.net/posts/2019/12/my-business-card-runs-linux/

  and while I have my board built, I seem to be having trouble with flashing.

  dmesg reports that my F1C100s is in FEL mode; however, when libusb tries to talk to it, the device disappears and reappears:

lsusb:

  Bus 009 Device 014: ID 1f3a:efe8 Allwinner Technology sunxi SoC OTG connector in FEL/flashing mode

dmesg:

  usb 9-6.1: new full-speed USB device number 15 using xhci_hcd
  usb 9-6.1: New USB device found, idVendor=1f3a, idProduct=efe8, bcdDevice= 2.b3
  usb 9-6.1: New USB device strings: Mfr=0, Product=0, SerialNumber=0

command:

  sudo LIBUSB_DEBUG="1" ./sunxi-fel --list --verbose
  libusb: error [get_usbfs_fd] libusb couldn't open USB device /dev/bus/usb/009/015, errno=5
  libusb_open() ERROR -1: Input/Output Error

subsequent dmesg:

  usb 9-6.1: reset full-speed USB device number 15 using xhci_hcd
  usb 9-6.1: USB disconnect, device number 15
  usb 9-6.1: new full-speed USB device number 16 using xhci_hcd
  usb 9-6.1: New USB device found, idVendor=1f3a, idProduct=efe8, bcdDevice= 2.b3
  usb 9-6.1: New USB device strings: Mfr=0, Product=0, SerialNumber=0

sunxi-fel version: v1.4.2-178-gdf60a46-dirty (master from github).

If there is more information that I can provide then please let me know! Unfortunately, I feel like I don't know what to ask, so my apologies if I'm forgetting something obvious or if this question is too vague.