1 files changed, 16 insertions, 4 deletions

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index debd30917010..26eb70c8f518 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -2110,7 +2110,8 @@ static int __init intel_opregion_present(void)
 
 int acpi_video_register(void)
 {
-        int result = 0;
+        int ret;
+
         if (register_count) {
                 /*
                  * if the function of acpi_video_register is already called,
@@ -2122,9 +2123,9 @@ int acpi_video_register(void)
         mutex_init(&video_list_lock);
         INIT_LIST_HEAD(&video_bus_head);
 
-        result = acpi_bus_register_driver(&acpi_video_bus);
-        if (result < 0)
-                return -ENODEV;
+        ret = acpi_bus_register_driver(&acpi_video_bus);
+        if (ret)
+                return ret;
 
         /*
          * When the acpi_video_bus is loaded successfully, increase
@@ -2176,6 +2177,17 @@ EXPORT_SYMBOL(acpi_video_unregister_backlight);
 
 static int __init acpi_video_init(void)
 {
+        /*
+         * Let the module load even if ACPI is disabled (e.g. due to
+         * a broken BIOS) so that i915.ko can still be loaded on such
+         * old systems without an AcpiOpRegion.
+         *
+         * acpi_video_register() will report -ENODEV later as well due
+         * to acpi_disabled when i915.ko tries to register itself afterwards.
+         */
+        if (acpi_disabled)
+                return 0;
+
         dmi_check_system(video_dmi_table);
 
         if (intel_opregion_present())