1 files changed, 18 insertions, 4 deletions

diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index b3480cf7db1a..d49f1e464703 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -256,6 +256,8 @@ int acpi_bus_init_power(struct acpi_device *device)
                 return -EINVAL;
 
         device->power.state = ACPI_STATE_UNKNOWN;
+        if (!acpi_device_is_present(device))
+                return 0;
 
         result = acpi_device_get_power(device, &state);
         if (result)
@@ -302,15 +304,18 @@ int acpi_device_fix_up_power(struct acpi_device *device)
         return ret;
 }
 
-int acpi_bus_update_power(acpi_handle handle, int *state_p)
+int acpi_device_update_power(struct acpi_device *device, int *state_p)
 {
-        struct acpi_device *device;
         int state;
         int result;
 
-        result = acpi_bus_get_device(handle, &device);
-        if (result)
+        if (device->power.state == ACPI_STATE_UNKNOWN) {
+                result = acpi_bus_init_power(device);
+                if (!result && state_p)
+                        *state_p = device->power.state;
+
                 return result;
+        }
 
         result = acpi_device_get_power(device, &state);
         if (result)
@@ -338,6 +343,15 @@ int acpi_bus_update_power(acpi_handle handle, int *state_p)
 
         return 0;
 }
+
+int acpi_bus_update_power(acpi_handle handle, int *state_p)
+{
+        struct acpi_device *device;
+        int result;
+
+        result = acpi_bus_get_device(handle, &device);
+        return result ? result : acpi_device_update_power(device, state_p);
+}
 EXPORT_SYMBOL_GPL(acpi_bus_update_power);
 
 bool acpi_bus_power_manageable(acpi_handle handle)