ACPI: Always check if _PRW is present before trying to evaluate it

Before evaluating _PRW for devices that are reported as inactive or
not present by their _STA control methods we should check if those
methods are actually present (otherwise the evaulation of _PRW will
obviously fail and a scary message will be printed unnecessarily).

Reported-by: Andreas Mohr <andi@lisas.de>
Reported-by: Maciej Rutecki <maciej.rutecki@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 64d4da0d6d5255bbbd7112f44c4d9a88f045fef0..b5e4dedb497d7331c6cd31721a712b0ce79ec723 100644 (file)
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1388,7 +1388,6 @@ static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
        struct acpi_bus_ops *ops = context;
        int type;
        unsigned long long sta;
-       struct acpi_device_wakeup wakeup;
        struct acpi_device *device;
        acpi_status status;
        int result;
@@ -1399,7 +1398,13 @@ static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
 
        if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
            !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
-               acpi_bus_extract_wakeup_device_power_package(handle, &wakeup);
+               struct acpi_device_wakeup wakeup;
+               acpi_handle temp;
+
+               status = acpi_get_handle(handle, "_PRW", &temp);
+               if (ACPI_SUCCESS(status))
+                       acpi_bus_extract_wakeup_device_power_package(handle,
+                                                                    &wakeup);
                return AE_CTRL_DEPTH;
        }