Hello Sebastien, On 17/01/18(Wed) 10:19, Sebastien Marie wrote: > [...] > kernel modification is desirable in some cases, at least for disabling > ulpt(4) when using cups with USB printer.
Sorry to hijack your thread, but if somebody wants to fix this ulpt(4) problem permanently here's the plan: - Add the USBD_EXCLUSIVE_USE to usbd_open_pipe() in ulptopen(). Actually this flag should be the default everywhere. This should prevent open(2) on /dev/ulpt? to work if a userland driver is using your printer. - Do some plumbing between libusb/ugen(4)/usb(4) to make it possible to submit bulk transfer via /dev/usb?. The logic in ugenopen() should also have the USBD_EXCLUSIVE_USE flag such that it will fail if the corresponding /dev/ultp? has already been opened. That should be enough to have CUPS work with GENERIC kernels without having to disable anything. I'm here to help/review diffs but since I don't have a printer myself, I can't do the work.
