Return-Path: <cyrus@holtmann.org>
Subject: Re: [rfc]btusb with SCO support
From: Marcel Holtmann <marcel@holtmann.org>
To: Oliver Neukum <oliver@neukum.org>
Cc: linux-bluetooth@vger.kernel.org, linux-usb@vger.kernel.org
In-Reply-To: <200808181638.51851.oliver@neukum.org>
References: <200807311452.24166.oliver@neukum.org>
	 <200808181627.27053.oliver@neukum.org>
	 <1219070182.7591.56.camel@violet.holtmann.net>
	 <200808181638.51851.oliver@neukum.org>
Content-Type: text/plain
Date: Mon, 18 Aug 2008 17:12:40 +0200
Message-Id: <1219072360.7591.59.camel@violet.holtmann.net>
Mime-Version: 1.0
Sender: linux-bluetooth-owner@vger.kernel.org
List-ID: <linux-bluetooth.vger.kernel.org>

Hi Oliver,

> > > > > > On the other hand, this is audio and I don't really care if we loose a
> > > > > > packet or not.
> > > > > 
> > > > > It isn't limited to sound. The URBs for acl reception can also be delayed
> > > > > arbitrarily long.
> > > > 
> > > > We can move that into the notify() callback, but the killing the URBs
> > > > becomes a problem.
> > > 
> > > /**
> > >  * usb_unlink_anchored_urbs - asynchronously cancel transfer requests en masse
> > >  * @anchor: anchor the requests are bound to
> > >  *
> > >  * this allows all outstanding URBs to be unlinked starting
> > >  * from the back of the queue. This function is asynchronous.
> > >  * The unlinking is just tiggered. It may happen after this
> > >  * function has returned.
> > >  */
> > > void usb_unlink_anchored_urbs(struct usb_anchor *anchor)
> > 
> > then we can move the ACL handling into the notify() callback.
> > 
> > For the SCO ones, I don't see any chance since we have to do the
> > altsetting first.
> 
> You are right.

actually we can't move the URB killing for ACL into notify() since that
gives me a kernel panic (fatal exception in interrupt).

Your patch for the IRQ disabling doesn't make a difference.

Regards

Marcel