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Date: Wed, 27 Oct 2010 10:13:09 -0700
From: "H. Peter Anvin" <hpa@linux.intel.com>
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Subject: [Qemu-devel] Re: [PATCH 5/6] Add support for a USB audio device
	model
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To: Gerd Hoffmann <kraxel@redhat.com>
Cc: qemu-devel@nongnu.org

On 10/27/2010 9:04 AM, Gerd Hoffmann wrote:
> From: H. Peter Anvin<hpa@linux.intel.com>
>
> This brings a usb audio device to qemu.  Output only, fixed at
> 16bit stereo @ 480000 Hz.  Based on a patch from
> H. Peter Anvin<hpa@linux.intel.com>
>
> Usage: add '-device usb-audio' to your qemu command line.
>
> Works sorta ok on a idle machine.  Known issues:
>
>   * Is *very* sensitive to latencies: when the uhci emulation misses one
>     of the usb frame rate wakeups (1k/sec!) you'll loose/delay data from
>     the audio stream, resulting in dropouts.
>   * Also seems to not play very well with the usb tablet (and/or usb hub,
>     to be investigated).  Best try this as the only device on a usb bus.
>   * Burns quite some CPU due to usb polling.
>
> In short:  It brings the qemu usb emulation to its limits.  Enjoy!
>
> Signed-off-by: Gerd Hoffmann<kraxel@redhat.com>

Please don't apply this.  This patch is outdated and has several glaring 
bugs.  I can send a better patch later (I'm in an all-day meeting with 
insanely bad networking.)

	-hpa