Messages in this thread | | | Date | Mon, 20 Apr 2015 09:56:40 -0400 (EDT) | From | Alan Stern <> | Subject | Re: [RFC][PATCH v2 06/13] usb: hcd: Add hcd add/remove functions for OTG use |
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On Mon, 20 Apr 2015, Roger Quadros wrote:
> > I don't understand this. Why do you want to defer the add/remove if > > the device is OTG? Don't host controller drivers expect these things > > to execute synchronously? > > Sorry for the wrong information. We actually defer only the add as the > OTG state machine might not yet be in Host ready mode. > The remove is always synchronous and we ensure that the HCD is removed > when usb_otg_unregister_hcd() returns.
That's okay then, but it does leave one potential hole. What happens if usb_add_hcd() is deferred for so long that usb_remove_hcd() gets called before the add can complete?
Alan Stern
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