Alan Stern wrote: > On Mon, 30 Apr 2012, Grzegorz Nosek wrote: > >> W dniu 30.04.2012 23:12, Alan Stern pisze: >>> It isn't a software issue. You've got a hardware problem; either the >>> IPKVM itself, or the connecting cable, or your computer's EHCI >>> controller is bad. The only reason the device worked without the retry >>> logic is because it failed so completely that the kernel was forced to >>> run it at full speed (12 Mb/s) instead of high speed (480 Mb/s). With >>> the retry logic present, the device was barely workable at high speed >>> (but it probably didn't work well enough to be very useful). >> >> Oh. Thanks for the info. Is there a way to force the device into 12Mb/s >> mode? I don't care about performance as the bottleneck is my Internet >> link on the client, anyway. The retry logic rendered the console >> unusable (not just slow, completely no keyboard or redirected media). > > In fact there _is_ a way to do it: > > echo 7 >/sys/bus/pci/devices/0000:00:1d.7/companion > > Here 7 is the number of the port which you want to force to full speed > and 0000:00:1d.7 is the PCI address of the EHCI controller. BTW, when I have a USB3 device detected at high-speed only, how can force it to super-speed? What filename should I write the echo value? # lsusb Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 003 Device 008: ID 046d:c050 Logitech, Inc. RX 250 Optical Mouse Bus 003 Device 007: ID 174c:5106 ASMedia Technology Inc. Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 003: ID 05ca:1820 Ricoh Co., Ltd Bus 002 Device 003: ID 138a:0011 Validity Sensors, Inc. VFS5011 Fingerprint Reader Bus 002 Device 004: ID 0bda:0138 Realtek Semiconductor Corp. Card reader # Hmm, I do not have the proper file even for full-speed? # echo 7 > /sys/bus/pci/devices/0000\:11\:00.0/companion -su: /sys/bus/pci/devices/0000:11:00.0/companion: No such file or directory # Thanks, Martin -- 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
