I have a USB to serial adapter. It works OK with my desktop computer, but no on my laptop. My desktop PC is a generic computer (Athlon 64 X2 6000+ on board MSI K9AGM, 6 USB 2.0 ports, no USB 3.0 ports), and my laptop is an HP ENVY4-1015DX (2 USB 2.0 ports, 1 USB 3.0 port)
My desktop has Ubuntu 12.04.2 64 bits, kernel 3.5.0-37. When I plug it into any USB port on this PC, I got this in kern.log:
Sep 9 15:31:07 amdx2 kernel: [ 57.968035] usb 4-2: new full-speed USB device number 2 using ohci_hcd
Sep 9 15:31:07 amdx2 kernel: [ 58.128306] usb 4-2: New USB device found, idVendor=4348, idProduct=5523
Sep 9 15:31:07 amdx2 kernel: [ 58.128311] usb 4-2: New USB device strings: Mfr=0, Product=0, SerialNumber=0
Sep 9 15:31:07 amdx2 kernel: [ 58.302088] usbcore: registered new interface driver usbserial
Sep 9 15:31:07 amdx2 kernel: [ 58.302530] usbcore: registered new interface driver usbserial_generic
Sep 9 15:31:07 amdx2 kernel: [ 58.302544] USB Serial support registered for generic
Sep 9 15:31:07 amdx2 kernel: [ 58.302548] usbserial: USB Serial Driver core
Sep 9 15:31:07 amdx2 kernel: [ 58.318155] usbcore: registered new interface driver ch341
Sep 9 15:31:07 amdx2 kernel: [ 58.318178] USB Serial support registered for ch341-uart
Sep 9 15:31:07 amdx2 kernel: [ 58.318194] ch341 4-2:1.0: ch341-uart converter detected
Sep 9 15:31:07 amdx2 kernel: [ 58.340514] usb 4-2: ch341-uart converter now attached to ttyUSB0
However, when I plug exactly the same adapter with the same USB cable into any port on my laptop (it doesn't matters if I plug it into a USB 2.0 or USB 3.0 port), I got:
Sep 9 15:31:50 envy4 kernel: [10776.099052] usb 3-1: new full-speed USB device number 37 using xhci_hcd
Sep 9 15:31:50 envy4 kernel: [10776.115364] usb 3-1: device descriptor read/8, error -71
Sep 9 15:31:50 envy4 kernel: [10776.235486] usb 3-1: device descriptor read/8, error -71
Sep 9 15:31:50 envy4 kernel: [10776.450932] usb 3-1: new full-speed USB device number 38 using xhci_hcd
Sep 9 15:31:50 envy4 kernel: [10776.467242] usb 3-1: device descriptor read/8, error -71
Sep 9 15:31:50 envy4 kernel: [10776.587459] usb 3-1: device descriptor read/8, error -71
Sep 9 15:31:50 envy4 kernel: [10776.802756] usb 3-1: new full-speed USB device number 39 using xhci_hcd
Sep 9 15:31:50 envy4 kernel: [10776.819142] usb 3-1: device descriptor read/8, error -71
Sep 9 15:31:51 envy4 kernel: [10776.939484] usb 3-1: device descriptor read/8, error -71
Sep 9 15:31:51 envy4 kernel: [10777.042877] hub 3-0:1.0: unable to enumerate USB device on port 1
My laptop has Ubuntu 12.04.3 64 bits, kernel 3.8.0-30.
I see that the main difference is that, in my PC, Ubuntu uses driver ohci_hcd, and in my laptop Ubuntu uses xhci_hcd. I've tried doing:
sudo modprobe ohci_hcd
And also tried:
sudo modprobe -r xhci_hcd
However, none of these works. In first case, no error at modprobe, but system still uses xhci_hcd. In second case, on modprobe it gives me an error:
FATAL: Module xhci_hcd is builtin
What else could I do to solve my issue? Thanks!