http://bugzilla.opensuse.org/show_bug.cgi?id=1189466 Bug ID: 1189466 Summary: usb-relay board ch341a no longer working with kernels newer than ~ 5.3.18-lp152.57 Classification: openSUSE Product: openSUSE Distribution Version: Leap 15.2 Hardware: x86-64 OS: openSUSE Leap 15.2 Status: NEW Severity: Normal Priority: P5 - None Component: Kernel Assignee: kernel-bugs@opensuse.org Reporter: mail@hjmayer.de QA Contact: qa-bugs@suse.de Found By: --- Blocker: --- Created attachment 851793 --> http://bugzilla.opensuse.org/attachment.cgi?id=851793&action=edit log files with debug output I'm operating a usb-relay board based on chip ch341a on suse linux leap 15.2. As a driver program I use a small pure c-program written by Edwin van de Oetelaar (https://github.com/olerem/ch341a-relay-board). The program worked fine until I upgraded the kernel from 5.3.18-lp152.57 to 5.3.18-lp152.75. Also a newer kernel 5.10.4 showed the same behavior. All return codes from libusb-1.0 routines like libusb_get_device_list libusb_open_device_with_vid_pid libusb_kernel_driver_active libusb_detach_kernel_driver libusb_claim_interface libusb_bulk_transfer are identical and behave well when calling the program under either kernel, however the relays simply don't work under the newer kernels. Also when running with LIBUSB_DEBUG=4, no relevant differences between both logs arise. No Errors and no warnings. The only difference I notice is, that when running the application after pluging in the device, for the new kernels the kernel driver is active and must be detached (which is reported to happen successfully). With the working kernel, the kernel driver is not reported to be active and must therefore not being detached. I believe, that this is a kernel problem, because the kernel is the only difference when running the application. I add debug output of the application for command switch_relay -z 31 1 2 (should switch relay 1 and 2 on) with LIBUSB_DEBUG set to 4 for kernel 5.3.18 and 5.10.4 and output of command lsusb -v -d 1a86:5512 (I had to put it in 1 file because only 1 file as attachment is possible) Thanks a lot hago -- You are receiving this mail because: You are on the CC list for the bug.