On Tue, 11 Aug 2015, Alan Stern wrote: > On Tue, 11 Aug 2015, Bjørn Mork wrote: > > > Oliver Neukum <[email protected]> writes: > > > > >> I hope some of the USB experts can tell us what the correct behaviour > > >> is > > >> here. Should the driver treat EPROTO like ESHUTDOWN? Or should the > > >> host controller use some ESHUTDOWN instead? > > > > > > No. ESHUTDOWN is reserved for the removal of the HC. > > > > Then I have to ask: Why do I see ESHUTDOWN when I pull the modem from > > one of my ehci-pci ports? > > That error code might come from something other than an URB status > value. The ehci-hcd driver uses ESHUTDOWN only when the EHCI hardware > itself is inaccessible -- either because the controller is suspended > (D3) or because the driver is unbinding.
I almost forgot; there is one other place where ESHUTDOWN occurs. The USB core somewhat inconsistently uses that code when it cancels all the outstanding URBs on an endpoint. This happens when the endpoint is going away, typically because the device has been unplugged but possibly also as a result of a driver unbind or a configuration or altsetting change. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
