On Mon, 31 Oct 2011, Anton Alekseev wrote: > > This patch increases the delay time to 2 ms and adds some debugging > > log entries. Be sure that CONFIG_PRINTK_TIME is turned on, and post > > the dmesg from your test with both patches applied. > > dmesg in attachment Here are the last few lines: [ 185.221503] ehci_hcd 0000:00:12.2: disable periodic 0 [ 185.224194] ehci_hcd 0000:00:12.2: enable periodic 0 [ 195.579463] ehci_hcd 0000:00:12.2: start disable periodic [ 195.579476] ehci_hcd 0000:00:12.2: disable periodic 0 [ 195.583681] ehci_hcd 0000:00:12.2: force halt; handshake f801a024 00004000 00000000 -> -110 [ 195.583693] ehci_hcd 0000:00:12.2: enable periodic -110 [ 195.583699] ehci_hcd 0000:00:12.2: HC died; cleaning up We can see that even 4 ms after the second "disable periodic", the failed handshake indicates the controller still has not actually turned off the periodic schedule. There's one more thing you might try. In drivers/usb/host/ehci-sched.c, the disable_periodic() routine, change the last argument to handshake_on_error_set_halt() from 9 * 125 to something larger, such as 20 * 125. Keep the other patches applied as well, and let's see what happens. 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