[lkml]   [2015]   [Apr]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [RFC][PATCH v2 06/13] usb: hcd: Add hcd add/remove functions for OTG use
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

 \ /
  Last update: 2015-04-20 16:21    [W:0.063 / U:0.792 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site