linux-kernel - Re: [PATCH v3 1/3] ACPI / button: Remove initial lid state notification

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Date:	Thu, 23 Jun 2016 02:36:09 +0200
From:	"Rafael J. Wysocki" <rjw@...ysocki.net>
To:	Lv Zheng <lv.zheng@...el.com>
Cc:	"Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
	Len Brown <len.brown@...el.com>, Lv Zheng <zetalog@...il.com>,
	linux-kernel@...r.kernel.org, linux-acpi@...r.kernel.org
Subject: Re: [PATCH v3 1/3] ACPI / button: Remove initial lid state notification

On Wednesday, June 01, 2016 06:10:34 PM Lv Zheng wrote:
> The _LID control method's initial returning value is not reliable.
> 
> The _LID control method is described to return the "current" lid state.
> However the word of "current" has ambiguity, many BIOSen return the lid
> state upon the last lid notification instead of returning the lid state
> upon the last _LID evaluation. There won't be difference when the _LID
> control method is evaluated during the runtime, the problem is its initial
> returning value. When the BIOSen implement this control method with cached
> value, the initial returning value is likely not reliable. There are simply
> so many examples retuning "close" as initial lid state (Link 1), sending
> this state to the userspace causes suspending right after booting/resuming.
> 
> Since the lid state is implemented by the BIOSen, the kernel lid driver has
> no idea how it can be correct, this patch stops sending the initial lid
> state to the userspace to try to avoid sending the wrong lid state to the
> userspace to trigger such kind of wrong suspending. This actually reverts
> the following commit introduced for fixing a novell bug (Link 2):
>   Commit: 23de5d9ef2a4bbc4f733f58311bcb7cf6239c813
>   Subject: ACPI: button: send initial lid state after add and resume
> 
> Link 1: https://bugzilla.kernel.org/show_bug.cgi?id=89211
>         https://bugzilla.kernel.org/show_bug.cgi?id=106151
>         https://bugzilla.kernel.org/show_bug.cgi?id=106941
> Link 2: https://bugzilla.novell.com/show_bug.cgi?id=326814
> Signed-off-by: Lv Zheng <lv.zheng@...el.com>

I've applied [1-3/3] from this series, but I'm not sure if the last patch
is the latest version.  Can you please verify in linux-next?

Thanks,
Rafael