On Tue, 15 Apr 2014, Stefani Seibold wrote: > > One other thing you can try is to increase the reset timeout in > > drivers/usb/host/ehci-hub.c. This is under the USB_PORT_FEAT_RESET > > case in ehci_hub_control(), around line 1225: > > > > /* > > * caller must wait, then call GetPortStatus > > * usb 2.0 spec says 50 ms resets on root > > */ > > ehci->reset_done [wIndex] = jiffies > > + msecs_to_jiffies (50); > > > > Increasing the 50 to 100 or more might help. > > > > Alan Stern > > > > I tried this, when i increase the value to 1000, the reset and > enumeration process will be faster after a kexec: 28 Seconds vs. 162 > Seconds.
Even 28 seconds is much longer than it should be. And a 1000-ms long reset signal is a lot longer than any device should need. Anyway, since you saw the same problem after unbind and rebind, you don't have to perform a kexec for testing. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html