Working - I appreciate this.  I applied this mini-patch to kernel
4.8.1 and confirm that after a few test scans, I now have no problem
with the USB Canon scanner.

Also seems to have cleared up a puzzling no-input problem I was having
with a cheap no-brand USB keyboard/video/mouse switch under 4.8.1.



On Fri, Oct 14, 2016 at 3:52 PM, Bryan Paluch <> wrote:
> I've been experiencing similar issues with usb audio headsets. There is an
> issue for ubuntu 16.10 here
> .
> I was able to fix the issue by changing the IO_WATCHDOG_DELAY in ohci-hcd.c
> from 250 msec to 275 msec. I suspect that the new timer wheel based timers
> in 4.8 have exposed a bug in the ohci driver. Before the io watchdog timer
> was set to 250 with 20 msecs of slack time. This is more than likely just a
> hacky work around but I'm able to use my usb headphones now. Here's my diff
> diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
> index 1700908..86612ac 100644
> --- a/drivers/usb/host/ohci-hcd.c
> +++ b/drivers/usb/host/ohci-hcd.c
> @@ -72,7 +72,7 @@
>  static const char hcd_name [] = "ohci_hcd";
>  #define STATECHANGE_DELAY msecs_to_jiffies(300)
> -#define IO_WATCHDOG_DELAY msecs_to_jiffies(250)
> +#define IO_WATCHDOG_DELAY msecs_to_jiffies(275)
>  #include "ohci.h"
>  #include "pci-quirks.h"
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