linux-kernel - Re: [PATCH] ACPI LID: increment wakeup count only when notified.

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Date:   Thu, 7 Jun 2018 01:21:24 +0200
From:   "Rafael J. Wysocki" <rafael@...nel.org>
To:     Benson Leung <bleung@...gle.com>
Cc:     "Rafael J. Wysocki" <rafael@...nel.org>,
        Ravi Chandra Sadineni <ravisadineni@...omium.org>,
        "Rafael J. Wysocki" <rjw@...ysocki.net>,
        Len Brown <lenb@...nel.org>,
        Ravi Chandra Sadineni <ravisadineni@...gle.com>,
        Dmitry Torokhov <dmitry.torokhov@...il.com>,
        Todd Broch <tbroch@...gle.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        ACPI Devel Maling List <linux-acpi@...r.kernel.org>,
        Rajat Jain <rajatja@...gle.com>,
        Furquan Shaikh <furquan@...omium.org>,
        Benson Leung <bleung@...omium.org>
Subject: Re: [PATCH] ACPI LID: increment wakeup count only when notified.

On Thu, Jun 7, 2018 at 1:11 AM, Benson Leung <bleung@...gle.com> wrote:
> Hi Rafael,
>
> On Wed, Jun 06, 2018 at 09:00:43AM +0200, Rafael J. Wysocki wrote:
>> > @@ -417,6 +414,7 @@ static void acpi_button_notify(struct acpi_device *device, u32 event)
>> >                 /* fall through */
>> >         case ACPI_BUTTON_NOTIFY_STATUS:
>> >                 input = button->input;
>> > +               acpi_pm_wakeup_event(&device->dev);
>>
>> Not really.
>>
>> There already is an acpi_pm_wakeup_event() call in the else branch below.
>>
>
> Ravi removes that other call below.

OK, I missed that, not sure why, sorry.

> The intent for this is to call
> acpi_pm_wakeup_event() regardless if the button->type is ACPI_BUTTON_TYPE_LID,
> in case that event is ACPI_BUTTON_NOTIFY_STATUS.

Well, the patch really drops the acpi_pm_wakeup_event() call from
acpi_lid_notify_state() and so it has to ensure that this function
will be called here for ACPI_BUTTON_NOTIFY_STATUS regardless of the
button->type value.

That's fine, but still the changelog doesn't make it clear why the
acpi_pm_wakeup_event() call in acpi_lid_notify_state() is not
necessary in general.

Thanks,
Rafael