1 files changed, 42 insertions, 0 deletions
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index 237a8d73a096..9c7e6d7ea1b3 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -385,6 +385,45 @@ void uml_pm_wake(void)
 	pm_system_wakeup();
 }
 
+static int um_suspend_valid(suspend_state_t state)
+{
+	return state == PM_SUSPEND_MEM;
+}
+
+static int um_suspend_prepare(void)
+{
+	um_irqs_suspend();
+	return 0;
+}
+
+static int um_suspend_enter(suspend_state_t state)
+{
+	if (WARN_ON(state != PM_SUSPEND_MEM))
+		return -EINVAL;
+
+	/*
+	 * This is identical to the idle sleep, but we've just
+	 * (during suspend) turned off all interrupt sources
+	 * except for the ones we want, so now we can only wake
+	 * up on something we actually want to wake up on. All
+	 * timing has also been suspended.
+	 */
+	um_idle_sleep();
+	return 0;
+}
+
+static void um_suspend_finish(void)
+{
+	um_irqs_resume();
+}
+
+const struct platform_suspend_ops um_suspend_ops = {
+	.valid = um_suspend_valid,
+	.prepare = um_suspend_prepare,
+	.enter = um_suspend_enter,
+	.finish = um_suspend_finish,
+};
+
 static int init_pm_wake_signal(void)
 {
 	/*
@@ -397,6 +436,9 @@ static int init_pm_wake_signal(void)
 	 */
 	if (time_travel_mode != TT_MODE_EXTERNAL)
 		register_pm_wake_signal();
+
+	suspend_set_ops(&um_suspend_ops);
+
 	return 0;
 }