Subject: Re: Add a "enable" sysfs attribute to the pci devices to allow
	userspace (Xorg) to enable devices without doing foul direct access
From: Arjan van de Ven <arjan@linux.intel.com>
To: Jon Smirl <jonsmirl@gmail.com>
Cc: greg@kroah.com, linux-pci@atrey.karlin.mff.cuni.cz,
       linux-kernel@vger.kernel.org, airlied@linux.ie, pjones@redhat.com,
       akpm@osdl.org
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	 <9e4733910605020959k7aad853dn87d73348cbcf42cd@mail.gmail.com>
	 <44579028.1020201@linux.intel.com>
	 <9e4733910605021013h17b72453v3716f68a2cebdee1@mail.gmail.com>
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Date: Tue, 02 May 2006 20:27:37 +0200
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On Tue, 2006-05-02 at 13:13 -0400, Jon Smirl wrote:
> On 5/2/06, Arjan van de Ven <arjan@linux.intel.com> wrote:
> > Jon Smirl wrote:
> > > All of these have been proposed before.
> >
> > I think you forgot to attach the patch
> >
> > > In my opinion an 'enable'
> > > attribute is the worst solution in the bunch.
> >
> > you again limit yourself to VGA. I don't.
> 
> Haven't we learned that mucking with hardware from user space without
> having a device driver loaded is a very bad idea.

Not quite. It needs a reasonable sane userspace sure, but it's not
unreasonable for several cases.

>   What is the
> motivation for providing an API whose only purpose is to enable this
> bad behavior?

you're very selective in what you read and only think about X.
There's many other reasons to enable/disable devices post boot. 
Having a driver just to call pci_enable_device() is silly; and
there are various scenarios you may want. Userland suspend/resume is
only one of those, posting video cards is one, chip health monitoring is
one, etc etc etc. Don't let your lack of imagination ruin things.


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