On Mon, 16 Apr 2012, Martin Mokrejs wrote: > Hmm, this time I reproduced it without the generic-usb lines, only this was logged: > > [ 587.121578] hub 2-1.2:1.0: port 1 disabled by hub (EMI?), re-enabling... > [ 587.122106] usb 2-1.2.1: USB disconnect, device number 6 > [ 587.364517] usb 2-1.2.1: new low-speed USB device number 8 using ehci_hcd > [ 587.482332] usb 2-1.2.1: New USB device found, idVendor=04f2, idProduct=0116 > [ 587.482335] usb 2-1.2.1: New USB device strings: Mfr=1, Product=2, SerialNumber=0 > [ 587.482336] usb 2-1.2.1: Product: USB Keyboard > [ 587.482337] usb 2-1.2.1: Manufacturer: CHICONY > [ 587.487259] input: CHICONY USB Keyboard as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2.1/2-1.2.1:1.0/input/input16 > [ 587.487367] generic-usb 0003:04F2:0116.0003: input,hidraw0: USB HID v1.10 Keyboard [CHICONY USB Keyboard] on usb-0000:00:1d.0-1.2.1/input0 > > But, the usbmon trace is attached, along lspci and dmesg for completeness. Here is the interesting part of the usbmon trace. The second column is a timestamp, in microseconds. ffff88040bfea600 1294425758 C Ii:2:007:1 0:8 5 = 00000100 00 ffff88040bfea600 1294425784 S Ii:2:007:1 -115:8 5 < These two lines show a successful report from the mouse. ffff88040a276bc0 1315464647 C Ii:2:006:1 -71:8 0 ffff88040a276bc0 1315481572 S Ii:2:006:1 -115:8 8 < ffff88040a276bc0 1315504644 C Ii:2:006:1 -71:8 0 These three lines show two failed attempts to send a packet to the keyboard. The packets couldn't be sent because the keyboard's port was disabled. ffff88040cc382c0 1315527406 C Ii:2:005:1 0:2048 1 = 02 ffff88040cc382c0 1315527419 S Ii:2:005:1 -115:2048 1 < ffff88040dbc62c0 1315527576 S Ci:2:005:0 s a3 00 0000 0001 0004 4 < ffff88040dbc62c0 1315527891 C Ci:2:005:0 0 4 = 01030200 These lines show the port status data from the hub. The status says that port 1 was automatically disabled, by the hub (not by the computer). ffff88040dbc62c0 1315528014 S Co:2:005:0 s 23 01 0011 0001 0000 0 ffff88040dbc62c0 1315528395 C Co:2:005:0 0 0 This shows the computer telling the hub to turn off the "disabled" status bit for the port. It's right about at this time that the "EMI" message gets logged. The rest of the usbmon trace shows the keyboard being re-enumerated as device 8, and being used along with the mouse. Alan Stern -- 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
