From 43739b9a32cbe45139935bbeb39aecf7b7dd017c Mon Sep 17 00:00:00 2001
From: Adam Jackson <ajax@redhat.com>
Date: Fri, 14 Mar 2008 14:24:21 -0400
Subject: [PATCH] RANDR 1.2: Fix initial mode aspect ratio match in a corner
 case.

Actually more like in the mainline case, where the ideal mode happens to
be the very first aspect match on the first monitor.  But let's not
split hairs.
(cherry picked from commit 824853772241acf64bc37ac8b85254194741ae13)
---
 hw/xfree86/modes/xf86Crtc.c | 55 +++++++++++++++++++------------------
 1 file changed, 29 insertions(+), 26 deletions(-)

diff --git a/hw/xfree86/modes/xf86Crtc.c b/hw/xfree86/modes/xf86Crtc.c
index 0bef5b42f..2b074217d 100644
--- a/hw/xfree86/modes/xf86Crtc.c
+++ b/hw/xfree86/modes/xf86Crtc.c
@@ -1674,14 +1674,19 @@ aspectMatch(float a, float b)
 }
 
 static DisplayModePtr
-nextAspectMode(DisplayModePtr start, float aspect)
+nextAspectMode(xf86OutputPtr o, DisplayModePtr last, float aspect)
 {
-    DisplayModePtr m = start;
+    DisplayModePtr m = NULL;
 
-    if (!m)
+    if (!o)
 	return NULL;
 
-    for (m = m->next; m; m = m->next)
+    if (!last)
+	m = o->probed_modes;
+    else
+	m = last->next;
+
+    for (; m; m = m->next)
 	if (aspectMatch(aspect, (float)m->HDisplay / (float)m->VDisplay))
 	    return m;
 
@@ -1691,31 +1696,29 @@ nextAspectMode(DisplayModePtr start, float aspect)
 static DisplayModePtr
 bestModeForAspect(xf86CrtcConfigPtr config, Bool *enabled, float aspect)
 {
-    int o, p;
-    DisplayModePtr mode, test = NULL, match = NULL;
+    int o = -1, p;
+    DisplayModePtr mode = NULL, test = NULL, match = NULL;
 
-    for (o = -1; nextEnabledOutput(config, enabled, &o); ) {
-	mode = config->output[o]->probed_modes;
-	while ((mode = nextAspectMode(mode, aspect))) {
-	    for (p = o; nextEnabledOutput(config, enabled, &p); ) {
-		test = xf86OutputFindClosestMode(config->output[p], mode);
-		if (!test)
-		    break;
-		if (test->HDisplay != mode->HDisplay ||
-		    test->VDisplay != mode->VDisplay) {
-		    test = NULL;
-		    break;
-		}
-	    }
-
-	    /* if we didn't match it on all outputs, try the next one */
+    nextEnabledOutput(config, enabled, &o);
+    while ((mode = nextAspectMode(config->output[o], mode, aspect))) {
+	for (p = o; nextEnabledOutput(config, enabled, &p); ) {
+	    test = xf86OutputFindClosestMode(config->output[p], mode);
 	    if (!test)
-		continue;
-
-	    /* if it's bigger than the last one, save it */
-	    if (!match || (test->HDisplay > match->HDisplay))
-		match = test;
+		break;
+	    if (test->HDisplay != mode->HDisplay ||
+		    test->VDisplay != mode->VDisplay) {
+		test = NULL;
+		break;
+	    }
 	}
+
+	/* if we didn't match it on all outputs, try the next one */
+	if (!test)
+	    continue;
+
+	/* if it's bigger than the last one, save it */
+	if (!match || (test->HDisplay > match->HDisplay))
+	    match = test;
     }
 
     /* return the biggest one found */