mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Mathias Nyman <mathias.nyman@linux.intel.com>
To: Lu Baolu <baolu.lu@linux.intel.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Mathias Nyman <mathias.nyman@intel.com>,
	Alan Stern <stern@rowland.harvard.edu>
Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v5 3/3] usb: xhci: remove stop device and ring doorbell in hub control and bus suspend
Date: Thu, 25 Jun 2015 17:53:09 +0300	[thread overview]
Message-ID: <558C15D5.9020802@linux.intel.com> (raw)
In-Reply-To: <1431134130-7922-4-git-send-email-baolu.lu@linux.intel.com>

On 09.05.2015 04:15, Lu Baolu wrote:
> There is no need to call xhci_stop_device() and xhci_ring_device() in
> hub control and bus suspend functions since all device suspend and
> resume have been notified through device_suspend/device_resume interfaces.

I was looking through this code again before sending it forward, and it occurred to
me that this might be breaking the PORT_SUSPEND and PORT_SET_LINK_STATE port features
for xhci root hub.

In normal use these requests are called by usb core in usb_port_suspend(), which 
also now notifies xhci, which makes sure xhci_stop_device() is called. 

But I don't think there is anything preventing an URB to be sent to the xhci roothub
with a PORT_SUSPEND or PORT_SET_LINK_STATE port feature request. In this case the usb_port_suspend()
is not called, and no notify will stop the device. 

For example hub validation tests might do this

-Mathias




  reply	other threads:[~2015-06-25 14:50 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-05-09  1:15 [PATCH v5 0/3] usb: notify hcd when USB device suspend or resume Lu Baolu
2015-05-09  1:15 ` [PATCH v5 1/3] " Lu Baolu
2015-05-09  1:15 ` [PATCH v5 2/3] usb: xhci: implement device_suspend/device_resume entries Lu Baolu
2015-06-01  1:49   ` Greg Kroah-Hartman
2015-05-09  1:15 ` [PATCH v5 3/3] usb: xhci: remove stop device and ring doorbell in hub control and bus suspend Lu Baolu
2015-06-25 14:53   ` Mathias Nyman [this message]
2015-06-26  4:52     ` Lu, Baolu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=558C15D5.9020802@linux.intel.com \
    --to=mathias.nyman@linux.intel.com \
    --cc=baolu.lu@linux.intel.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --cc=mathias.nyman@intel.com \
    --cc=stern@rowland.harvard.edu \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome