ACPI button: don't try to use a non-existent lid device

If a call comes in to check the lid state but there's no lid device
present, we should return -ENODEV.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c
index 9335b87..0c9c6a9 100644 (file)
--- a/drivers/acpi/button.c
+++ b/drivers/acpi/button.c
@@ -251,6 +251,9 @@ int acpi_lid_open(void)
        acpi_status status;
        unsigned long long state;
 
+       if (!lid_device)
+               return -ENODEV;
+
        status = acpi_evaluate_integer(lid_device->handle, "_LID", NULL,
                                       &state);
        if (ACPI_FAILURE(status))