linux-kernel - Re: [PATCH v3 4/4] Input: Don't send fake button presses to wake system

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Message-ID: <9c2d7405-4c6f-49f4-ab40-0db821db6bea@kernel.org>
Date: Thu, 26 Jun 2025 13:47:28 -0500
From: Mario Limonciello <superm1@...nel.org>
To: Hans de Goede <hansg@...nel.org>
Cc: Mika Westerberg <westeri@...nel.org>,
 Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
 Linus Walleij <linus.walleij@...aro.org>, Bartosz Golaszewski
 <brgl@...ev.pl>, "open list:GPIO ACPI SUPPORT" <linux-gpio@...r.kernel.org>,
 "open list:GPIO ACPI SUPPORT" <linux-acpi@...r.kernel.org>,
 open list <linux-kernel@...r.kernel.org>,
 "open list:INPUT (KEYBOARD, MOUSE, JOYSTICK, TOUCHSCREEN)..."
 <linux-input@...r.kernel.org>, Mario Limonciello
 <mario.limonciello@....com>, Dmitry Torokhov <dmitry.torokhov@...il.com>
Subject: Re: [PATCH v3 4/4] Input: Don't send fake button presses to wake
 system

On 6/26/2025 1:45 PM, Hans de Goede wrote:
> Hi,
> 
> On 26-Jun-25 20:42, Mario Limonciello wrote:
>> On 6/26/2025 1:37 PM, Hans de Goede wrote:
>>> Hi Mario,
>>>
>>> On Thu, Jun 26, 2025 at 06:33:08AM -0500, Mario Limonciello wrote:
>>>>
>>>>
>>>> On 6/26/25 3:35 AM, Hans de Goede wrote:
>>>>> Hi Mario,
>>>>>
>>>>> On 25-Jun-25 23:58, Mario Limonciello wrote:
>>>>>> From: Mario Limonciello <mario.limonciello@....com>
>>>>>>
>>>>>> Sending an input event to wake a system does wake it, but userspace picks
>>>>>> up the keypress and processes it.  This isn't the intended behavior as it
>>>>>> causes a suspended system to wake up and then potentially turn off if
>>>>>> userspace is configured to turn off on power button presses.
>>>>>>
>>>>>> Instead send a PM wakeup event for the PM core to handle waking the system.
>>>>>>
>>>>>> Cc: Hans de Goede <hansg@...nel.org>
>>>>>> Fixes: 0f107573da417 ("Input: gpio_keys - handle the missing key press event in resume phase")
>>>>>> Signed-off-by: Mario Limonciello <mario.limonciello@....com>
>>>>>> ---
>>>>>>     drivers/input/keyboard/gpio_keys.c | 7 +------
>>>>>>     1 file changed, 1 insertion(+), 6 deletions(-)
>>>>>>
>>>>>> diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
>>>>>> index 773aa5294d269..4c6876b099c43 100644
>>>>>> --- a/drivers/input/keyboard/gpio_keys.c
>>>>>> +++ b/drivers/input/keyboard/gpio_keys.c
>>>>>> @@ -420,12 +420,7 @@ static irqreturn_t gpio_keys_gpio_isr(int irq, void *dev_id)
>>>>>>             pm_stay_awake(bdata->input->dev.parent);
>>>>>>             if (bdata->suspended  &&
>>>>>>                 (button->type == 0 || button->type == EV_KEY)) {
>>>>>> -            /*
>>>>>> -             * Simulate wakeup key press in case the key has
>>>>>> -             * already released by the time we got interrupt
>>>>>> -             * handler to run.
>>>>>> -             */
>>>>>> -            input_report_key(bdata->input, button->code, 1);
>>>>>> +            pm_wakeup_event(bdata->input->dev.parent, 0);
>>>>>>             }
>>>>>>         }
>>>>>
>>>>> Hmm, we have the same problem on many Bay Trail / Cherry Trail
>>>>> windows 8 / win10 tablets, so  this has been discussed before and e.g.
>>>>> Android userspace actually needs the button-press (evdev) event to not
>>>>> immediately go back to sleep, so a similar patch has been nacked in
>>>>> the past.
>>>>>
>>>>> At least for GNOME this has been fixed in userspace by ignoring
>>>>> power-button events the first few seconds after a resume from suspend.
>>>>>
>>>>
>>>> The default behavior for logind is:
>>>>
>>>> HandlePowerKey=poweroff
>>>
>>> Right note poweroff not suspend, GNOME inhibits logind's power-button
>>> handling and substitutes its own handling which is done by gsd-media-keys.
>>>
>>>> Can you share more about what version of GNOME has a workaround?
>>>> This was actually GNOME (on Ubuntu 24.04) that I found this issue.
>>>
>>> See:
>>>
>>> https://gitlab.gnome.org/GNOME/gnome-settings-daemon/-/blob/main/plugins/media-keys/gsd-media-keys-manager.c?ref_type=heads#L94
>>>
>>> and the code in that file using that define.
>>>
>>> Regards,
>>>
>>> Hans
>>>
>>
>> This is pretty ancient, it's part of GNOME 40 and later.  Ubuntu 24.04 is GNOME 46.
> 
> Right, this power-button evdev key event on resume causing an immediate
> suspend again is a pretty old problem. When I said "discussed before"
> I meant discussed quite a while ago :)
> 
> Regards,
> 
> Hans
> 

:)

I'm quite used to most platforms using ACPI power button which doesn't 
send a key press event during the resume sequence, so this is the first 
exposure for me to it.