ACPI: EC: Return bool from acpi_ec_dispatch_gpe()

On some systems, if suspend-to-idle is used, the EC may signal system
wakeup events (power button events, for example) as well as events
that should not cause the system to resume and acpi_ec_dispatch_gpe()
needs to be called to determine whether or not the system should
resume then.  In particular, if acpi_ec_dispatch_gpe() doesn't detect
any EC events at all, the system should remain suspended, so it is
useful to know when that is the case.

For this reason, make acpi_ec_dispatch_gpe() return a bool value
indicating whether or not any EC events have been detected by it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index c33756e..58c7ad4 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -1060,10 +1060,15 @@ void acpi_ec_set_gpe_wake_mask(u8 action)
 		acpi_set_gpe_wake_mask(NULL, first_ec->gpe, action);
 }
 
-void acpi_ec_dispatch_gpe(void)
+bool acpi_ec_dispatch_gpe(void)
 {
-	if (first_ec)
-		acpi_dispatch_gpe(NULL, first_ec->gpe);
+	u32 ret;
+
+	if (!first_ec)
+		return false;
+
+	ret = acpi_dispatch_gpe(NULL, first_ec->gpe);
+	return ret == ACPI_INTERRUPT_HANDLED;
 }
 
 /* --------------------------------------------------------------------------