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

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Message-ID: <3a1e2e0c-cbb9-4e3a-aa5a-9f88e8f05bc5@kernel.org>
Date: Thu, 26 Jun 2025 20:45:34 +0200
From: Hans de Goede <hansg@...nel.org>
To: Mario Limonciello <superm1@...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

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