I’m running a new desktop with one built-in USB controller and one extra USB controller from a PCI card. I passed through the built-in USB controller and plan to use the PCI card for anything other than keyboards and mice.
Unfortunately, I just can’t get my microphone or camera working through the PCI card. I’ve had it randomly work on certain occasions, but 90% of the time it won’t work.
In most case, when I go into my USB qube and run lsusb, I get this output:
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 0627:0001 Adomax Technology Co., Ltd QEMU Tablet
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
If I plug in my microphone, sometimes I’ll get that output, and other times I’ll see this:
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 0627:0001 Adomax Technology Co., Ltd QEMU Tablet
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 002: ID 2109:2822 VIA Labs, Inc. [unknown]
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 002: ID 2109:0822 VIA Labs, Inc. [unknown]
I’ve bolded the two new lines. If I use readlink (readlink /sys/bus/usb/devices/usb2 and readlink /sys/bus/usb/devices/usb3), sure enough they’ve got the same PCI address as the PCI card I’m passing through.
Why isn’t it working? 
On very rare occasions, things will work perfectly and I have no idea why. I managed to get to this state right now after restarting my USB qube (changing no settings in the process). Here’s the output of lsusb:
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 2109:2822 VIA Labs, Inc. [unknown]
Bus 001 Device 003: ID 0c45:6366 Microdia Webcam Vitade AF
Bus 001 Device 004: ID 0d8c:0005 C-Media Electronics, Inc. Blue Snowball
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 002: ID 2109:0822 VIA Labs, Inc. [unknown]
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 0627:0001 Adomax Technology Co., Ltd QEMU Tablet
See how both my camera and microphone are attached to bus 1? Weird, I’d of thought they’d attach to bus 2 or 3. Here’s the output of readlink for each now:
[user@sys-usb ~]$ readlink /sys/bus/usb/devices/usb1
…/…/…/devices/pci0000:00/0000:00:06.0/usb1
[user@sys-usb ~]$ readlink /sys/bus/usb/devices/usb2
…/…/…/devices/pci0000:00/0000:00:06.0/usb2
[user@sys-usb ~]$ readlink /sys/bus/usb/devices/usb3
…/…/…/devices/pci0000:00/0000:00:05.0/usb3
That 0000:00:06.0 is the PCI address of the PCI card that I’m passing into the USB qube, so that’s what we’d expect:
[user@sys-usb ~]$ lspci
00:00.0 Host bridge: Intel Corporation 440FX - 82441FX PMC [Natoma] (rev 02)
00:01.0 ISA bridge: Intel Corporation 82371SB PIIX3 ISA [Natoma/Triton II]
00:01.1 IDE interface: Intel Corporation 82371SB PIIX3 IDE [Natoma/Triton II]
00:01.3 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 03)
00:02.0 Unassigned class [ff80]: XenSource, Inc. Xen Platform Device (rev 01)
00:04.0 VGA compatible controller: Device 1234:1111 (rev 02)
00:05.0 USB controller: Intel Corporation 82801DB/DBM (ICH4/ICH4-M) USB2 EHCI Controller (rev 10)
00:06.0 USB controller: ASMedia Technology Inc. ASM2142/ASM3142 USB 3.1 Host Controller
Why is it working?
To summarize, Sometimes running lsusb on the USB qube fails to recognize anything is plugged in. Other times, it realizes something changed but can’t recognize it. In either case, I don’t see the new device in dom0, either from running qvm-usb or looking at the Qubes Devices GUI. Rarely, everything will work and I don’t understand why.
Things I’ve tried:
- Removing usbcore.authorized_defaults=0 from the GRUB boot options
- Removing rd.qubes.hide_all_usb from the GRUB boot options
- Removing both of the above
- Setting no strict reset for the PCI card when I pass it through
- Plugging the camera/microphone into different ports
Any advice?