Workaround for inability to scan on USB 3.0 port

12qu · 2014-07-27 03:55:37

I've got a late 2012 era Mac Mini (specifications here) that I'm trying to set up as a printing and scanner server for my Brother MFC-7340.

Long story short, I have discovered that scanning does not work when the MFC-7340 is plugged in to a USB 3.0 port. In this case, scanimage returns the following error:

scanimage: open of device brother3:bus4;dev2 failed: Invalid argument

and does not scan. This occurs on both my Mac Mini and my laptop (both running Arch) when plugged into a USB 3.0 port. When I plug the scanner in to a USB 2.0 port on my laptop, however, scanimage is successful.

I have found some mentions of this as a bug here and here, though unfortunately there is no mention of a solution beyond plugging the device in to a USB 2.0 port. However, this is not an option for my Mac Mini since all of its ports are USB 3.0.

As such, I am wondering whether there is any way to force a USB 3.0 port to function as a USB 2.0 port? Failing that, would anyone have any ideas of other possible workarounds? Note I have attempted all the possible fixes/workarounds listed in the first answer to this question on askubuntu that I was able to -- I didn't set "XHCI Pre-Boot mode", for example, since AFAIK Apple provides no mechanism for changing BIOS/UEFI options.

As a final note, I am fairly certain that I am not facing any fundamental hardware limitation that would prevent this setup, since I have been able to use the same scanner with the Mac Mini from inside OSX.

Buddlespit · 2014-07-27 04:02:19

does it help to add iommu=soft to the kernel command line?

12qu · 2014-07-27 04:11:39

No luck unfortunately, though I get the follow line in journalctl:

Jul 27 14:07:35 macmini kernel: [Firmware Bug]: ioapic 2 has no mapping iommu, interrupt remapping will be disabled

Would this indicate that that option isn't working correctly? (Note though that I get that message regardless of whether iommu=soft is on the command line.)

WonderWoofy · 2014-07-27 05:01:21

I wonder if it would be possible to use the ehci-hcd module instead of the xhci-hcd. I have no idea if this is a legitimate idea or not, but it is just the first thing that popped into my head.

12qu · 2014-07-27 05:12:34

How would I test this out? Would blacklisting xhci-hcd cause ehci-hcd to be loaded automatically as its replacement?

EDIT: I blacklisted xhci-hcd, updated my initramfs and rebooted. xhci_hcd was gone from lsmod, and ehci_hcd had been loaded, so that all seems to have worked. However, now when I run scanimage, for example, I get

# scanimage > out.pnm
scanimage: no SANE devices found

and lsusb can no longer see the scanner (and for that matter can't see an external HDD I have plugged in either).

Last edited by 12qu (2014-07-27 10:37:11)

WonderWoofy · 2014-07-27 21:35:07

Yeah, that is how I would have tried to apply echi_hcd instead of xhci_hcd. Too bad it didn't work.

Sorry, that was the only idea I had....

mcloaked · 2014-09-10 21:53:01

I have seen a Ubuntu posting saying that where xsane has a problem with usb3 connected usb2 scanners the vuescan package may handle it. I have been struggling with this same issue on a Canoscan LIDE210 and I have only just seen this advice/suggestion so I will be testing my own scanner with vuescan (which is in AUR). I'd be interested to know if vuescan copes with your scanner on usb3 or not?

mcloaked · 2014-09-11 09:09:22

I have tested my Canoscan LIDE 210 this morning connected to a laptop with only USB3 ports - and it works flawlessly with vuescan where it hangs when using xsane. I may take this up on the sane-devel list as it seems to indicate that there is a bug concerning USB3 in the sane code.

Arch Linux

#1 2014-07-27 03:55:37

Workaround for inability to scan on USB 3.0 port

#2 2014-07-27 04:02:19

Re: Workaround for inability to scan on USB 3.0 port

#3 2014-07-27 04:11:39

Re: Workaround for inability to scan on USB 3.0 port

#4 2014-07-27 05:01:21

Re: Workaround for inability to scan on USB 3.0 port

#5 2014-07-27 05:12:34

Re: Workaround for inability to scan on USB 3.0 port

#6 2014-07-27 21:35:07

Re: Workaround for inability to scan on USB 3.0 port

#7 2014-09-10 21:53:01

Re: Workaround for inability to scan on USB 3.0 port

#8 2014-09-11 09:09:22

Re: Workaround for inability to scan on USB 3.0 port

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