On Tue, Nov 18, 2014 at 4:20 PM, Rafael J. Wysocki <rjw@xxxxxxxxxxxxx> wrote: > It goes again below with a changelog, but since technically it is a regression > fix, I'd like to push it for "stable" too. I suppose that the commit that > things stopped working after is a76e9bd89ae7 (i2c: attach/detach I2C client > device to the ACPI power domain). Is that correct? Yes. > > Rafael > > > -- > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > Subject: ACPI / PM: Ignore wakeup setting if the ACPI companion can't wake up > > As reported by Dmitry, on some Chromebooks there are devices with > corresponding ACPI objects and with unusual system wakeup > configuration. Namely, they technically are wakeup-capable, but the > wakeup is handled via a platform-specific out-of-band mechanism > rather than by standard ACPI means. I think they are using standard ACPI wakeup methods, but in a very perverted way: there is "shadow" ACPI sleep button corresponding to the GPIO assigned to the trackpad or touchscreen; it is just not tied to touchpad/touchscreen device in DSDT. We won't have such set up again, but we do have existing boxes that are like that. > As a result, the > device_may_wakeup(dev) called from acpi_dev_suspend_late() returns > 'true' for them, but the wakeup.flags.valid flag is unset for the > corresponding ACPI device objects, so acpi_dev_suspend_late() > reproducibly returns an error for them causing the entire system > suspend to be aborted. Consequently, system suspend doesn't work > on those machines at all. > > Address the problem by ignoring the device_may_wakeup(dev) return > value in acpi_dev_suspend_late() if the ACPI companion of the device > in question has wakeup.flags.valid unset (in which case it is clear > that the wakeup cannot happen via ACPI). > > Reported-by: Dmitry Torokhov <dtor@xxxxxxxxxxxx> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > --- > drivers/acpi/device_pm.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > Index: linux-pm/drivers/acpi/device_pm.c > =================================================================== > --- linux-pm.orig/drivers/acpi/device_pm.c > +++ linux-pm/drivers/acpi/device_pm.c > @@ -878,7 +878,7 @@ int acpi_dev_suspend_late(struct device > return 0; > > target_state = acpi_target_system_state(); > - wakeup = device_may_wakeup(dev); > + wakeup = device_may_wakeup(dev) && acpi_device_can_wakeup(adev); > error = acpi_device_wakeup(adev, target_state, wakeup); > if (wakeup && error) > return error; > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
