RE: [PATCH v2] usb: xhci: Don't drive port 2.0 reset while resuming

From	Alan Stern <stern@rowland.harvard.edu>
Newsgroups	linux.kernel
Subject	RE: [PATCH v2] usb: xhci: Don't drive port 2.0 reset while resuming
Date	2016-10-26 16:40 +0200
Message-ID	<swxwZ-4Y6-1@gated-at.bofh.it> (permalink)
References	<swvYe-3Qk-23@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Wed, 26 Oct 2016, Sriram Dash wrote:

> >From: Mathias Nyman [mailto:mathias.nyman@linux.intel.com]

> >I don't think usb core tries to drive reset while port is still resuming
> >
> 
> I am skeptical about it and hope somebody may help us on this.

You can see for yourself.  In drivers/usb/core/hub.c, the 
usb_reset_device() routine calls usb_autoresume_device() before calling 
usb_reset_and_verify_device().  Therefore the port will have finished
resuming before the reset signal is sent.

Alan Stern

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Re: [PATCH v2] usb: xhci: Don't drive port 2.0 reset while resuming Mathias Nyman <mathias.nyman@linux.intel.com> - 2016-10-25 15:00 +0200
  RE: [PATCH v2] usb: xhci: Don't drive port 2.0 reset while resuming Sriram Dash <sriram.dash@nxp.com> - 2016-10-26 15:00 +0200
    RE: [PATCH v2] usb: xhci: Don't drive port 2.0 reset while resuming Alan Stern <stern@rowland.harvard.edu> - 2016-10-26 16:40 +0200

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