--- zzzz-none-000/linux-3.10.107/drivers/platform/x86/msi-wmi.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/drivers/platform/x86/msi-wmi.c	2021-02-04 17:41:59.000000000 +0000
@@ -29,6 +29,7 @@
 #include <linux/backlight.h>
 #include <linux/slab.h>
 #include <linux/module.h>
+#include <acpi/video.h>
 
 MODULE_AUTHOR("Thomas Renninger <trenn@suse.de>");
 MODULE_DESCRIPTION("MSI laptop WMI hotkeys driver");
@@ -320,7 +321,8 @@
 		break;
 	}
 
-	if (wmi_has_guid(MSIWMI_BIOS_GUID) && !acpi_video_backlight_support()) {
+	if (wmi_has_guid(MSIWMI_BIOS_GUID) &&
+	    acpi_video_get_backlight_type() == acpi_backlight_vendor) {
 		err = msi_wmi_backlight_setup();
 		if (err) {
 			pr_err("Unable to setup backlight device\n");
@@ -354,8 +356,7 @@
 		sparse_keymap_free(msi_wmi_input_dev);
 		input_unregister_device(msi_wmi_input_dev);
 	}
-	if (backlight)
-		backlight_device_unregister(backlight);
+	backlight_device_unregister(backlight);
 }
 
 module_init(msi_wmi_init);