On Sat, Feb 8, 2025 at 5:22 PM Mario Limonciello <superm1@xxxxxxxxxx> wrote: > > From: Mario Limonciello <mario.limonciello@xxxxxxx> > > On Windows the OS will wake up when plugged or unplugged from AC adapter. > Depending upon whether the system was plugged in or unplugged will > determine whether the "display turns on". If there is no user activity > for some time then it goes back to sleep. > > In Linux plugging or unplugging an adapter will wake the SoC from HW > sleep but then the Linux kernel puts it right back into HW sleep > immediately unless there is another interrupt active (such as a PME or > GPIO). > > To get closer to the Windows behavior, record the state of the battery > when going into suspend and compare it when updating battery status > during the s2idle loop. If it's changed, wake the system. > > This can be restored to previous behavior by disabling the ACPI battery > device `power/wakeup` sysfs file. Why is this desirable? What if the AC is connected to a suspended laptop when the lid is still closed? Is it really a good idea to resume it then? Frankly, I'd prefer the existing behavior to be still the default. > Link: https://learn.microsoft.com/en-us/windows-hardware/design/device-experiences/modern-standby-wake-sources#environmental-context-changes-1 > Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx> > --- > drivers/acpi/battery.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c > index 72c8a509695e6..91f79927cc720 100644 > --- a/drivers/acpi/battery.c > +++ b/drivers/acpi/battery.c > @@ -125,6 +125,7 @@ struct acpi_battery { > int state; > int power_unit; > int capacity_suspend; > + int suspend_state; > unsigned long flags; > }; > > @@ -1012,6 +1013,12 @@ static inline bool acpi_battery_should_wake(struct acpi_battery *battery) > return true; > } > > + if (battery->state != battery->suspend_state) { > + pm_pr_dbg("Waking due to battery state changed from 0x%x to 0x%x", > + battery->suspend_state, battery->state); > + return true; > + } > + > return false; > } > > @@ -1313,6 +1320,7 @@ static int acpi_battery_suspend(struct device *dev) > return -EINVAL; > > battery->capacity_suspend = battery->capacity_now; > + battery->suspend_state = battery->state; > > return 0; > } > -- > 2.43.0 > >
