26 Jan 2017; same problem from syslog
Jan 26 08:36:17 USSMLTRDLinux02 kernel: [259338.868105] usb 2-1.1: new full-speed USB device number 38 using ehci-pci Jan 26 08:36:17 USSMLTRDLinux02 kernel: [259338.961091] usb 2-1.1: New USB device found, idVendor=1a86, idProduct=7523 Jan 26 08:36:17 USSMLTRDLinux02 kernel: [259338.961097] usb 2-1.1: New USB device strings: Mfr=0, Product=2, SerialNumber=0 Jan 26 08:36:17 USSMLTRDLinux02 kernel: [259338.961099] usb 2-1.1: Product: USB2.0-Ser! Jan 26 08:36:17 USSMLTRDLinux02 kernel: [259338.961389] ch341 2-1.1:1.0: ch341-uart converter detected Jan 26 08:36:17 USSMLTRDLinux02 kernel: [259338.963275] usb 2-1.1: ch341-uart converter now attached to ttyUSB1 Jan 26 08:36:17 USSMLTRDLinux02 mtp-probe: checking bus 2, device 38: "/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.1" Jan 26 08:36:17 USSMLTRDLinux02 mtp-probe: bus: 2, device: 38 was not an MTP device $ uname -a Linux USSMLTRDLinux02 3.13.0-107-generic #154~precise1-Ubuntu SMP Tue Dec 20 10:37:27 UTC 2016 i686 i686 i386 GNU/Linux I do observe the associated access is ehci-pci, whereas the original post access was xhci_hcd Also I have some CH341 bases RS485 interfaces, they work just fine, same VID:PID. The device having problems is RS232. These have a driver CD for Windows, works fine there. sys;log for the RS485 device Jan 26 08:48:04 USSMLTRDLinux02 kernel: [260046.435291] usb 2-1.4: USB disconnect, device number 37 Jan 26 08:48:07 USSMLTRDLinux02 kernel: [260049.195120] usb 2-1.4: new full-speed USB device number 39 using ehci-pci Jan 26 08:48:07 USSMLTRDLinux02 kernel: [260049.288782] usb 2-1.4: New USB device found, idVendor=1a86, idProduct=7523 Jan 26 08:48:07 USSMLTRDLinux02 kernel: [260049.288788] usb 2-1.4: New USB device strings: Mfr=0, Product=2, SerialNumber=0 Jan 26 08:48:07 USSMLTRDLinux02 kernel: [260049.288791] usb 2-1.4: Product: USB2.0-Serial Jan 26 08:48:07 USSMLTRDLinux02 kernel: [260049.289149] ch341 2-1.4:1.0: ch341-uart converter detected Jan 26 08:48:07 USSMLTRDLinux02 kernel: [260049.291092] usb 2-1.4: ch341-uart converter now attached to ttyUSB2 Jan 26 08:48:07 USSMLTRDLinux02 mtp-probe: checking bus 2, device 39: "/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.4" Jan 26 08:48:07 USSMLTRDLinux02 mtp-probe: bus: 2, device: 39 was not an MTP device I note in RS232 description: Jan 26 08:36:17 USSMLTRDLinux02 kernel: [259338.961099] usb 2-1.1: Product: USB2.0-Ser! and in RS485 description: Jan 26 08:48:07 USSMLTRDLinux02 kernel: [260049.288791] usb 2-1.4: Product: USB2.0-Serial interesting how the description in syslog also corrupts -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1527491 Title: QinHeng Electronics HL-340 USB-Serial adapter Status in linux package in Ubuntu: Confirmed Bug description: USB serial adapter detected but not working. $ lsusb Bus 001 Device 125: ID 1a86:7523 QinHeng Electronics HL-340 USB-Serial adapter $ ls /dev/ttyU* /dev/ttyUSB0 From syslog Dec 18 09:35:23 pieter-ThinkPad kernel: [487228.018937] usb 1-1: new full-speed USB device number 126 using xhci_hcd Dec 18 09:35:23 pieter-ThinkPad kernel: [487228.183954] usb 1-1: New USB device found, idVendor=1a86, idProduct=7523 Dec 18 09:35:23 pieter-ThinkPad kernel: [487228.183959] usb 1-1: New USB device strings: Mfr=0, Product=2, SerialNumber=0 Dec 18 09:35:23 pieter-ThinkPad kernel: [487228.183962] usb 1-1: Product: USB2.0-Ser! Dec 18 09:35:23 pieter-ThinkPad kernel: [487228.184731] ch341 1-1:1.0: ch341-uart converter detected Dec 18 09:35:23 pieter-ThinkPad kernel: [487228.185569] usb 1-1: ch341-uart converter now attached to ttyUSB0 Dec 18 09:35:23 pieter-ThinkPad mtp-probe: checking bus 1, device 126: "/sys/devices/pci0000:00/0000:00:14.0/usb1/1-1" Dec 18 09:35:23 pieter-ThinkPad mtp-probe: bus: 1, device: 126 was not an MTP device $ uname -a Linux pieter-ThinkPad 4.3.0-040300-lowlatency #201511020949 SMP PREEMPT Mon Nov 2 14:55:33 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux Google search http://comments.gmane.org/gmane.linux.usb.general/121851 https://bugzilla.redhat.com/show_bug.cgi?id=1235715 http://unix.stackexchange.com/questions/189896/testing-if-hl-340-works --- ApportVersion: 2.19.1-0ubuntu5 Architecture: amd64 CurrentDesktop: Unity DistroRelease: Ubuntu 15.10 InstallationDate: Installed on 2015-01-23 (331 days ago) InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2) Package: linux (not installed) Tags: wily Uname: Linux 4.3.0-040300-lowlatency x86_64 UnreportableReason: The running kernel is not an Ubuntu kernel UpgradeStatus: Upgraded to wily on 2015-11-11 (39 days ago) UserGroups: adm btsync cdrom dialout dip kismet kvm libvirtd lpadmin plugdev sambashare sudo wireshark _MarkForUpload: True To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1527491/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp