linux-kernel - Re: [PATCH] platform/x86/amd/pmc: Only disable IRQ1 wakeup where i8042 actually enabled it

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Message-ID: <e27e0e0e-a3a9-7b11-4e7d-27274eab604f@linux.intel.com>
Date: Sun, 29 Dec 2024 19:19:25 +0200 (EET)
From: Ilpo Järvinen <ilpo.jarvinen@...ux.intel.com>
To: "Maciej S. Szmigiero" <mail@...iej.szmigiero.name>
cc: Shyam Sundar S K <Shyam-sundar.S-k@....com>, 
    Mario Limonciello <mario.limonciello@....com>, 
    Hans de Goede <hdegoede@...hat.com>, platform-driver-x86@...r.kernel.org, 
    LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] platform/x86/amd/pmc: Only disable IRQ1 wakeup where
 i8042 actually enabled it

On Sun, 29 Dec 2024, Maciej S. Szmigiero wrote:

> On 29.12.2024 17:58, Ilpo Järvinen wrote:
> > On Sun, 29 Dec 2024, Maciej S. Szmigiero wrote:
> > 
> > > Wakeup for IRQ1 should be disabled only in cases where i8042 had actually
> > > enabled it, otherwise "wake_depth" for this IRQ will try do drop below
> > > zero
> > > and there will be an unpleasant WARN() logged:
> > > kernel: atkbd serio0: Disabling IRQ1 wakeup source to avoid platform
> > > firmware bug
> > > kernel: ------------[ cut here ]------------
> > > kernel: Unbalanced IRQ 1 wake disable
> > > kernel: WARNING: CPU: 10 PID: 6431 at kernel/irq/manage.c:920
> > > irq_set_irq_wake+0x147/0x1a0
> > > 
> > > To fix this call the PMC suspend handler only from the same set of
> > > dev_pm_ops handlers as i8042_pm_suspend() is called, which currently means
> > > just the ".suspend" handler.
> > > Previously, the code would use DEFINE_SIMPLE_DEV_PM_OPS() to define its
> > > dev_pm_ops, which also called this handler on ".freeze" and ".poweroff".
> > > 
> > > To reproduce this issue try hibernating (S4) the machine after a fresh
> > > boot
> > > without putting it into s2idle first.
> > > 
> > > Fixes: 8e60615e8932 ("platform/x86/amd: pmc: Disable IRQ1 wakeup for
> > > RN/CZN")
> > > Signed-off-by: Maciej S. Szmigiero <mail@...iej.szmigiero.name>
> > > ---
> > >   drivers/platform/x86/amd/pmc/pmc.c | 8 +++++++-
> > >   1 file changed, 7 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/platform/x86/amd/pmc/pmc.c
> > > b/drivers/platform/x86/amd/pmc/pmc.c
> > > index 26b878ee5191..a254debb9256 100644
> > > --- a/drivers/platform/x86/amd/pmc/pmc.c
> > > +++ b/drivers/platform/x86/amd/pmc/pmc.c
> > > @@ -947,6 +947,10 @@ static int amd_pmc_suspend_handler(struct device
> > > *dev)
> > >   {
> > >   	struct amd_pmc_dev *pdev = dev_get_drvdata(dev);
> > >   +	/*
> > > +	 * Must be called only from the same set of dev_pm_ops handlers
> > > +	 * as i8042_pm_suspend() is called: currently just from .suspend.
> > > +	 */
> > >   	if (pdev->disable_8042_wakeup && !disable_workarounds) {
> > >   		int rc = amd_pmc_wa_irq1(pdev);
> > >   @@ -959,7 +963,9 @@ static int amd_pmc_suspend_handler(struct device
> > > *dev)
> > >   	return 0;
> > >   }
> > >   -static DEFINE_SIMPLE_DEV_PM_OPS(amd_pmc_pm, amd_pmc_suspend_handler,
> > > NULL);
> > > +static const struct dev_pm_ops amd_pmc_pm = {
> > > +	.suspend = amd_pmc_suspend_handler,
> > > +};
> > 
> > ???
> > 
> > I cannot see what this change is supposed to achieve.
> > 
> > #define _DEFINE_DEV_PM_OPS(name, \
> >                             suspend_fn, resume_fn, \
> >                             runtime_suspend_fn, runtime_resume_fn, idle_fn)
> > \
> > const struct dev_pm_ops name = { \
> >          SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
> >          RUNTIME_PM_OPS(runtime_suspend_fn, runtime_resume_fn, idle_fn) \
> > }
> > 
> > #define DEFINE_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
> >          _DEFINE_DEV_PM_OPS(name, suspend_fn, resume_fn, NULL, NULL, NULL)
> > 
> > #define SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
> >          .suspend = pm_sleep_ptr(suspend_fn), \
> >          .resume = pm_sleep_ptr(resume_fn), \
> >          .freeze = pm_sleep_ptr(suspend_fn), \
> >          .thaw = pm_sleep_ptr(resume_fn), \
> >          .poweroff = pm_sleep_ptr(suspend_fn), \
> >          .restore = pm_sleep_ptr(resume_fn),
> > 
> > #define pm_sleep_ptr(_ptr) PTR_IF(IS_ENABLED(CONFIG_PM_SLEEP), (_ptr))
> > 
> > Under what circumstances does this change result in some difference?
> > 
> 
> .freeze and .poweroff are now both NULL, just like in the i8042 driver.
> 
> As I wrote in the commit message:
> > > Previously, the code would use DEFINE_SIMPLE_DEV_PM_OPS() to define its
> > > dev_pm_ops, *which also called this handler on ".freeze" and ".poweroff".*

Also, please avoid using "previously" like this. I interpreted it like 
some old kernel did that.

-- 
 i.