ACPI / PM: Do not power manage devices in unknown initial states

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / acpi / device_pm.c

diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index 3ef075b718703632481bf88c81377811bef0d340..164d609d7c9eb81216e9c3504686f25f9c6b76c1 100644 (file)
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -330,6 +330,12 @@ int acpi_bus_init_power(struct acpi_device *device)
                result = acpi_dev_pm_explicit_set(device, state);
                if (result)
                        return result;
+       } else if (state == ACPI_STATE_UNKNOWN) {
+               /* No power resources and missing _PSC? Try to force D0. */
+               state = ACPI_STATE_D0;
+               result = acpi_dev_pm_explicit_set(device, state);
+               if (result)
+                       return result;
        }
        device->power.state = state;
        return 0;