diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index 164d609d7c9e..dd314ef9bff1 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -355,6 +355,9 @@ int acpi_bus_update_power(acpi_handle handle, int *state_p)
 	if (result)
 		return result;
 
+	if (state == ACPI_STATE_UNKNOWN)
+		state = ACPI_STATE_D0;
+
 	result = acpi_device_set_power(device, state);
 	if (!result && state_p)
 		*state_p = state;