On Thu, 2019-07-04 at 21:37 -0400, Alan Stern wrote: > > > > Talking of which... do we need this ? > > > > --- a/drivers/usb/gadget/composite.c > > +++ b/drivers/usb/gadget/composite.c > > @@ -1976,6 +1976,7 @@ void composite_disconnect(struct usb_gadget *gadget) > > * disconnect callbacks? > > */ > > spin_lock_irqsave(&cdev->lock, flags); > > + cdev->suspended = 0; > > if (cdev->config) > > reset_config(cdev); > > if (cdev->driver->disconnect) > > > > Otherwise with my vhub or with dummy_hcd, a suspend followed by a reset > > will keep that stale suspended flag to 1 (which has no effect at the moment > > but still...) > > > > If yes, I'll submit a patch accordingly... > > According to the USB spec, a host is not supposed to reset a suspended > port (it's supposed to resume the port and then do the reset). But of > course this can happen anyway, so we should handle it properly. Right. I do see the resume coming in, but I don't forward it to the gadget because here's what happens in that order: 1- Host gets shutdown (or cable disconnected) 2- Upstream bus suspend: I call ->suspend on the gadgets on all enabled ports that don't have USB_PORT_STAT_SUSPEND already set. I don't change the port status, I don't set USB_PORT_STAT_SUSPEND 3- Machine gets turned back on (or cable reconnected) 4- Upstream bus resume: I call ->resume on the gadgets on all enabled ports that don't have USB_PORT_STAT_SUSPEND set. 5- Upstream bus reset: I call ->suspend on all enabled ports after clearing their status (I preserve only USB_PORT_STAT_SUSPEND and USB_PORT_STAT_POWER which is always set for me). Note: I currently do this even if the port had USB_PORT_STAT_SUSPEND set, so such as port will get a double suspend ... maybe I shouldn't. 6- Hosts sets port reset: I reset the gadget since it's already bound/enabled. It's still "suspended". So we do have a legitimate case of "reset while suspended". I'll tidy up the patch and submit it. Cheers, Ben.
