Input: i8042 - allow KBD and AUX ports to wake up from suspend-to-idle

While registering serio device for i8042, mark them as wakeup-capable
and check their user space wakeup settings in i8042_pm_suspend() and
i8042_pm_resume() to enable or disable, respectively, their interrupts
to wake up the system.

This makes it possible to use the PC keyboard to wake up the system
from suspend-to-idle, among other things, after writing "enabled" to
the keyboard serio device's power/wakeup sysfs attribute.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/serio/i8042.c

@@ -1162,13 +1162,32 @@ static int i8042_controller_resume(bool force_reset)
 
 static int i8042_pm_suspend(struct device *dev)
 {
+	int i;
+
 	i8042_controller_reset(true);
 
+	/* Set up serio interrupts for system wakeup. */
+	for (i = 0; i < I8042_NUM_PORTS; i++) {
+		struct serio *serio = i8042_ports[i].serio;
+
+		if (serio && device_may_wakeup(&serio->dev))
+			enable_irq_wake(i8042_ports[i].irq);
+	}
+
 	return 0;
 }
 
 static int i8042_pm_resume(struct device *dev)
 {
+	int i;
+
+	for (i = 0; i < I8042_NUM_PORTS; i++) {
+		struct serio *serio = i8042_ports[i].serio;
+
+		if (serio && device_may_wakeup(&serio->dev))
+			disable_irq_wake(i8042_ports[i].irq);
+	}
+
 	/*
 	 * On resume from S2R we always try to reset the controller
 	 * to bring it in a sane state. (In case of S2D we expect
@@ -1300,13 +1319,16 @@ static void __init i8042_register_ports(void)
 	int i;
 
 	for (i = 0; i < I8042_NUM_PORTS; i++) {
-		if (i8042_ports[i].serio) {
+		struct serio *serio = i8042_ports[i].serio;
+
+		if (serio) {
 			printk(KERN_INFO "serio: %s at %#lx,%#lx irq %d\n",
-				i8042_ports[i].serio->name,
+				serio->name,
 				(unsigned long) I8042_DATA_REG,
 				(unsigned long) I8042_COMMAND_REG,
 				i8042_ports[i].irq);
-			serio_register_port(i8042_ports[i].serio);
+			serio_register_port(serio);
+			device_set_wakeup_capable(&serio->dev, true);
 		}
 	}
 }