From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8202A25DCFD; Thu, 26 Jun 2025 18:55:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750964132; cv=none; b=UBAABUZU9VJgzgn12+dfc/g+Dua5FayEPBU7usf4tCUjCtndJDfHfeILoTH5zSy4J6u4COiVAfvF1gCTW8b3AEvs3gobg7DruDApBP60gM9A+63I+XCex6KZErrvXmqn1XUtiGxa9nDZGCZZsojvYk+7zJexFal1O1MX+feOFR4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750964132; c=relaxed/simple; bh=2MSQRQIblcpQP8DA7Pz6frwkJ3RUYpqhPsW9unAE8kU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=hO7y5Vaxewmsk/1fLtNN38MFOrLmSNzdZuboJqAkxNeZ4ydmUJ2UQ/UYAdKSnwHeCtvC7/tCCfcI+8OskU7m1oPwHecKTSbonfI2MdR2dCSYSvlOFNjU5XNwtDWjszLFb0yeILraKyzy02bipWdnaLjz679ZONJx+xf6hcVw/w8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DuGUE4rK; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="DuGUE4rK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DF38CC4CEEB; Thu, 26 Jun 2025 18:55:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1750964132; bh=2MSQRQIblcpQP8DA7Pz6frwkJ3RUYpqhPsW9unAE8kU=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=DuGUE4rKC6SBlejcZdaTd61N7ui6xeeOue56AFtbSLnPfM1BiuHOUhLNNx8djbNcj 3CXpL1QrOZ/Qfb3Ru7pf7Q8lMrKraV7roDhwe0Ga78XhOUc1l0+ndBfBGCOfV4MOfY rA26zXVOF+LLHJL/aq6QlZrabOWV8F3Hmo0q+k3yHaBhSs5o9omY+MD5pWKtDWiHxj Qz6IcU2xyUL32ZnPfw0b5j7KyPZnhte7PuBPEAUsTYNbS7oetUScUD3XgN496X+TE+ hp7NphSAtTEQS9dMjgx4UD8rpXCSJatm+K0JnQyX48A4J6Js5ETxvs6+f+jP2aNyNC k8ECOcuRRnepw== Message-ID: Date: Thu, 26 Jun 2025 13:55:29 -0500 Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 4/4] Input: Don't send fake button presses to wake system To: Dmitry Torokhov Cc: Hans de Goede , Mika Westerberg , Andy Shevchenko , Linus Walleij , Bartosz Golaszewski , "open list:GPIO ACPI SUPPORT" , "open list:GPIO ACPI SUPPORT" , open list , "open list:INPUT (KEYBOARD, MOUSE, JOYSTICK, TOUCHSCREEN)..." , Mario Limonciello References: <20250625215813.3477840-1-superm1@kernel.org> <20250625215813.3477840-5-superm1@kernel.org> <710f7c04-0099-4611-b2ea-4dd4219ad5e2@kernel.org> <23f30094-68cc-47fe-86e0-5289cb41e940@kernel.org> <363c2b92-4bfc-4537-9fca-025eef09526f@kernel.org> Content-Language: en-US From: Mario Limonciello In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 6/26/2025 1:48 PM, Dmitry Torokhov wrote: > On Thu, Jun 26, 2025 at 01:20:54PM -0500, Mario Limonciello wrote: >> On 6/26/2025 1:07 PM, Dmitry Torokhov wrote: >>> On Thu, Jun 26, 2025 at 12:53:02PM -0500, Mario Limonciello wrote: >>>> >>>> >>>> On 6/26/25 12:44 PM, Dmitry Torokhov 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 >>>>>>>> >>>>>>>> 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 >>>>>>>> Fixes: 0f107573da417 ("Input: gpio_keys - handle the missing key press event in resume phase") >>>>>>>> Signed-off-by: Mario Limonciello >>>>>>>> --- >>>>>>>> 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); >>>>> >>>>> There is already pm_stay_awake() above. >>>> >>>> But that doesn't help with the fact that userspace gets KEY_POWER from this >>>> and reacts to it. >>>> >>>>> >>>>>>>> } >>>>>>>> } >>>>>>> >>>>>>> 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 >>>>>> >>>>>> 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. >>>>>> >>>>>> Nonetheless if this is dependent on an Android userspace problem could we >>>>>> perhaps conditionalize it on CONFIG_ANDROID_BINDER_DEVICES? >>>>> >>>>> No it is not only Android, other userspace may want to distinguish >>>>> between normal and "dark" resume based on keyboard or other user >>>>> activity. >>>>> >>>>> Thanks. >>>>> >>>> In this specific case does the key passed up to satisfy this userspace >>>> requirement and keep it awake need to specifically be a fabricated >>>> KEY_POWER? >>>> >>>> Or could we find a key that doesn't require some userspace to ignore >>>> KEY_POWER? >>>> >>>> Maybe something like KEY_RESERVED, KEY_FN, or KEY_POWER2? >>> >>> The code makes no distinction between KEY_POWER and KEY_A or KEY_B, etc. >>> It simply passes event to userspace for processing. >> >> Right. I don't expect a problem with most keys, but my proposal is to >> special case KEY_POWER while suspended. If a key press event must be sent >> to keep Android and other userspace happy I suggest sending something >> different just for that situation. > > I do not know if userspace specifically looks for KEY_POWER or if it > looks for user input in general, and I'd rather be on safe side and not > mangle user input. > > As Hans mentioned, at least some userspace already prepared to deal with > this issue. And again, this only works if by the time ISR/debounce > runs the key is already released. What if it is still pressed? You still > going to observe KEY_POWER and need to suppress turning off the screen. > >> >> Like this: >> >> diff --git a/drivers/input/keyboard/gpio_keys.c >> b/drivers/input/keyboard/gpio_keys.c >> index 773aa5294d269..66e788d381956 100644 >> --- a/drivers/input/keyboard/gpio_keys.c >> +++ b/drivers/input/keyboard/gpio_keys.c >> @@ -425,7 +425,10 @@ static irqreturn_t gpio_keys_gpio_isr(int irq, void >> *dev_id) >> * already released by the time we got interrupt >> * handler to run. >> */ >> - input_report_key(bdata->input, button->code, 1); >> + if (button->code == KEY_POWER) >> + input_report_key(bdata->input, KEY_WAKEUP, >> 1); > > Just FYI: Here your KEY_WAKEUP is stuck forever. Thanks. > >> + else >> + input_report_key(bdata->input, button->code, >> 1); >> } >> } >> >> >> >>> >>> You need to fix your userspace. Even with your tweak it is possible for >>> userspace to get a normal key event "too early" and turn off the screen >>> again, so you still need to handle this situation. >>> >>> Thanks. >>> >> >> I want to note this driver works quite differently than how ACPI power >> button does. >> >> You can see in acpi_button_notify() that the "keypress" is only forwarded >> when not suspended [1]. Otherwise it's just wakeup event (which is what my >> patch was modeling). >> >> https://github.com/torvalds/linux/blob/v6.16-rc3/drivers/acpi/button.c#L461 >> [1] > > If you check acpi_button_resume() you will see that the events are sent > from there. Except that for some reason they chose to use KEY_WAKEUP and > not KEY_POWER, oh well. Unlike acpi button driver gpio_keys is used on > multiple other platforms. > > Thanks. > Well that would explain the difference, and git blame gives the history [1]. It's from enablement for Android with ACPI power button. That commit also mentions that Android can handle both POWER and WAKEUP from input device to wakeup the system. Non-Android userspace doesn't do anything with KEY_WAKEUP today. So this has me thinking the proposal I had above to special case KEY_POWER and translate to KEY_WAKEUP is the right way forward, just making sure to release the key as you rightfully pointed out. https://github.com/torvalds/linux/commit/16f70feaabe9fde0af703f2991d44a7589f0b6e3 [1]