On Sat, Jul 04, 2015 at 08:03:57PM +0300, Evgen Druzhynin wrote: > [1.] One line summary of the problem: > ch341 module fails on 4.1.1 kernel > > [2.] Full description of the problem/report: > It's not possible to work with Arduino board after installing 4.1.1. > ch341 fails and does not create /dev/ttyUSB0 (or /dev/ttyACM0) entry. > On 3.18 and 4.0.0 all was ok. > > [3.] Keywords: usb, serial, modules > > [4.] Kernel version (from /proc/version): > Linux version 4.1.1-040101-generic (kernel@gomeisa) (gcc version 4.6.3 > (Ubuntu/Linaro 4.6.3-1ubuntu5)) > > [5.] dmesg output: > [74788.109282] usb 1-3: new full-speed USB device number 65 using xhci_hcd > [74788.239496] usb 1-3: New USB device found, idVendor=1a86, idProduct=7523 > [74788.239504] usb 1-3: New USB device strings: Mfr=0, Product=2, SerialNumber=0 > [74788.240147] ch341 1-3:1.0: ch341-uart converter detected > [74788.240625] ch341-uart: probe of ttyUSB0 failed with error -71 > [79166.063535] usb 1-3: USB disconnect, device number 65 > [79166.063746] ch341 1-3:1.0: device disconnected Thanks for the report. This does not look like a usb-serial issue (as no suspicious change went into 4.1), but could possibly indicate a problem with the underlying xhci driver (I've added the xhci-maintainer Mathias on CC). In summary one of the control transfers during port probe fails with -EPROTO. Perhaps you could try to do a bisect to figure out which change between 4.0 and 4.1 caused the regression. Thanks, Johan -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
