From: jsg <jsg@openbsd.org>
Date: Fri, 9 Sep 2022 04:36:03 +0000 (+0000)
Subject: drm/i915/display: avoid warnings when registering dual panel backlight
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=a939c9caa94a8e07fd0858b16ba9b91bdc45904a;p=openbsd

drm/i915/display: avoid warnings when registering dual panel backlight

From Arun R Murthy
7828b5d0080a4621973ab5c680c4df0bc6d96437 in linux 5.15.y/5.15.66
868e8e5156a1f8d92ca83fdbac6fd52798650792 in mainline linux
---

diff --git a/sys/dev/pci/drm/i915/display/intel_backlight.c b/sys/dev/pci/drm/i915/display/intel_backlight.c
index 7d9415f064c..26e38894171 100644
--- a/sys/dev/pci/drm/i915/display/intel_backlight.c
+++ b/sys/dev/pci/drm/i915/display/intel_backlight.c
@@ -979,26 +979,26 @@ int intel_backlight_device_register(struct intel_connector *connector)
 	if (!name)
 		return -ENOMEM;
 
-	bd = backlight_device_register(name, connector->base.kdev, connector,
-				       &intel_backlight_device_ops, &props);
-
-	/*
-	 * Using the same name independent of the drm device or connector
-	 * prevents registration of multiple backlight devices in the
-	 * driver. However, we need to use the default name for backward
-	 * compatibility. Use unique names for subsequent backlight devices as a
-	 * fallback when the default name already exists.
-	 */
-	if (IS_ERR(bd) && PTR_ERR(bd) == -EEXIST) {
+	bd = backlight_device_get_by_name(name);
+	if (bd) {
+#ifdef __linux__
+		put_device(&bd->dev);
+#endif
+		/*
+		 * Using the same name independent of the drm device or connector
+		 * prevents registration of multiple backlight devices in the
+		 * driver. However, we need to use the default name for backward
+		 * compatibility. Use unique names for subsequent backlight devices as a
+		 * fallback when the default name already exists.
+		 */
 		kfree(name);
 		name = kasprintf(GFP_KERNEL, "card%d-%s-backlight",
 				 i915->drm.primary->index, connector->base.name);
 		if (!name)
 			return -ENOMEM;
-
-		bd = backlight_device_register(name, connector->base.kdev, connector,
-					       &intel_backlight_device_ops, &props);
 	}
+	bd = backlight_device_register(name, connector->base.kdev, connector,
+				       &intel_backlight_device_ops, &props);
 
 	if (IS_ERR(bd)) {
 		drm_err(&i915->drm,