From mboxrd@z Thu Jan  1 00:00:00 1970
From: yakui_zhao <yakui.zhao@intel.com>
Subject: Re: [Intel-gfx] RFC] [Patch] [DRM/I915] :Check the LID device to
	decide whether the LVDS should be initialized
Date: Mon, 15 Jun 2009 15:41:10 +0800
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To: "Alexander E. Patrakov" <patrakov@gmail.com>
Cc: "intel-gfx@lists.freedesktop.org" <intel-gfx@lists.freedesktop.org>, "Zhang, Rui" <rui.zhang@intel.com>, "linux-acpi@vger.kernel.org" <linux-acpi@vger.kernel.org>

On Sat, 2009-06-13 at 13:48 +0800, Alexander E. Patrakov wrote:
> 2009/6/11 yakui_zhao <yakui.zhao@intel.com>:
> > +       if (acpi_disabled) {
> > +               /*
> > +                * if ACPI is disabled, there is no ACPI device tree. And
> > +                * we don't know whether there exists the LID device.
> > +                * In such case we will return 0.
> > +                */
> > +               return 0;
> > +       }
> 
> Won't this prevent people from debugging ACPI problems on laptops by
> disabling ACPI on the kernel command line? Does this patch mean that,
> in such case, there will be no output at all? Maybe, without ACPI, we
> should initialize LVDS if and only if there are no other output
> devices connected?
No. It has no effect on LVDS output device if ACPI is disabled.
If the system is booted with acpi disabled, the function of intel_lvds_find_lid
will return zero and it will continue the current flowchart of LVDS output device.

Thanks.