Subject: Re: Add a "enable" sysfs attribute to the pci devices to allow
	userspace (Xorg) to enable devices without doing foul direct access
From: Peter Jones <pjones@redhat.com>
To: Jon Smirl <jonsmirl@gmail.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>, greg@kroah.com,
       linux-pci@atrey.karlin.mff.cuni.cz, linux-kernel@vger.kernel.org,
       airlied@linux.ie, akpm@osdl.org
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Organization: Red Hat, Inc.
Date: Tue, 02 May 2006 15:29:41 -0400
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On Tue, 2006-05-02 at 15:00 -0400, Jon Smirl wrote:
> I also can not see how user space suspend/resume can
> disable PCI hardware without coordinating with an active device
> driver.

And that's not a reasonable thing for userspace to do, if an active
device driver is using that.  But sometimes it might want to turn a
device on, perform some action, and then disable it again.

[...]
> You may call this silly but it is a real pain to spend hours debugging
> code only to discover that it failed because some other app unknown to
> you altered the state of the hardware while you were using it.

"Doctor, it hurts when I stab myself in the eye..."

-- 
  Peter

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