From 291bc9f827188461ff9717efccec1e350db537e8 Mon Sep 17 00:00:00 2001
From: Adam Jackson <ajax@redhat.com>
Date: Tue, 28 Jul 2009 11:07:13 -0400
Subject: [PATCH 3/7] RANDR: right-of placement by default

[Enhanced to add a new prefer clone option for drivers. This
allows for servers like RN50 where two heads are disjoint. - airlied]
---
 hw/xfree86/common/xf86str.h |    8 ++++-
 hw/xfree86/modes/xf86Crtc.c |   76 ++++++++++++++++++++++++++++++++++++++-----
 2 files changed, 75 insertions(+), 9 deletions(-)

diff --git a/hw/xfree86/common/xf86str.h b/hw/xfree86/common/xf86str.h
index 0590262..d246634 100644
--- a/hw/xfree86/common/xf86str.h
+++ b/hw/xfree86/common/xf86str.h
@@ -508,10 +508,13 @@ typedef struct _confdrirec {
 } confDRIRec, *confDRIPtr;
 
 /* These values should be adjusted when new fields are added to ScrnInfoRec */
-#define NUM_RESERVED_INTS		16
+#define NUM_RESERVED_INTS		15
 #define NUM_RESERVED_POINTERS		14
 #define NUM_RESERVED_FUNCS		10
 
+/* let clients know they can use this */
+#define XF86_SCRN_HAS_PREFER_CLONE 1
+
 typedef void *(*funcPointer) (void);
 
 /* flags for depth 24 pixmap options */
@@ -769,6 +772,9 @@ typedef struct _ScrnInfoRec {
     ClockRangePtr clockRanges;
     int adjustFlags;
 
+    /* initial rightof support disable */
+    int                 preferClone;
+
     /*
      * These can be used when the minor ABI version is incremented.
      * The NUM_* parameters must be reduced appropriately to keep the
diff --git a/hw/xfree86/modes/xf86Crtc.c b/hw/xfree86/modes/xf86Crtc.c
index 154f684..c58088d 100644
--- a/hw/xfree86/modes/xf86Crtc.c
+++ b/hw/xfree86/modes/xf86Crtc.c
@@ -1130,6 +1130,15 @@ xf86InitialOutputPositions(ScrnInfoPtr scrn, DisplayModePtr * modes)
     int o;
     int min_x, min_y;
 
+    /* check for initial right-of heuristic */
+    for (o = 0; o < config->num_output; o++)
+    {
+        xf86OutputPtr output = config->output[o];
+
+        if (output->initial_x || output->initial_y)
+            return TRUE;
+    }
+
     for (o = 0; o < config->num_output; o++) {
         xf86OutputPtr output = config->output[o];
 
@@ -1998,6 +2007,57 @@ bestModeForAspect(xf86CrtcConfigPtr config, Bool *enabled, float aspect)
     return match;
 }
 
+static int
+numEnabledOutputs(xf86CrtcConfigPtr config, Bool *enabled)
+{
+    int i = 0, p;
+
+    for (i = 0, p = -1; nextEnabledOutput(config, enabled, &p); i++) ;
+
+    return i;
+}
+
+static Bool
+xf86TargetRightOf(ScrnInfoPtr scrn, xf86CrtcConfigPtr config,
+                  DisplayModePtr *modes, Bool *enabled,
+                  int width, int height)
+{
+    int o;
+    int w = 0;
+
+    if (scrn->preferClone)
+        return FALSE;
+
+    if (numEnabledOutputs(config, enabled) < 2)
+        return FALSE;
+
+    for (o = -1; nextEnabledOutput(config, enabled, &o); ) {
+        DisplayModePtr mode =
+            xf86OutputHasPreferredMode(config->output[o], width, height);
+
+        if (!mode)
+            return FALSE;
+
+        w += mode->HDisplay;
+    }
+
+    if (w > width)
+        return FALSE;
+
+    w = 0;
+    for (o = -1; nextEnabledOutput(config, enabled, &o); ) {
+        DisplayModePtr mode =
+            xf86OutputHasPreferredMode(config->output[o], width, height);
+
+        config->output[o]->initial_x = w;
+        w += mode->HDisplay;
+
+        modes[o] = mode;
+    }
+
+    return TRUE;
+}
+
 static Bool
 xf86TargetPreferred(ScrnInfoPtr scrn, xf86CrtcConfigPtr config,
                     DisplayModePtr * modes, Bool *enabled,
@@ -2074,14 +2134,10 @@ xf86TargetPreferred(ScrnInfoPtr scrn, xf86CrtcConfigPtr config,
      */
     if (!ret)
         do {
-            int i = 0;
             float aspect = 0.0;
             DisplayModePtr a = NULL, b = NULL;
 
-            /* count the number of enabled outputs */
-            for (i = 0, p = -1; nextEnabledOutput(config, enabled, &p); i++);
-
-            if (i != 1)
+            if (numEnabledOutputs(config, enabled) != 1)
                 break;
 
             p = -1;
@@ -2385,6 +2441,8 @@ xf86InitialConfiguration(ScrnInfoPtr scrn, Bool canGrow)
     else {
         if (xf86TargetUserpref(scrn, config, modes, enabled, width, height))
             xf86DrvMsg(i, X_INFO, "Using user preference for initial modes\n");
+        else if (xf86TargetRightOf(scrn, config, modes, enabled, width, height))
+            xf86DrvMsg(i, X_INFO, "Using spanning desktop for initial modes\n");
         else if (xf86TargetPreferred
                  (scrn, config, modes, enabled, width, height))
             xf86DrvMsg(i, X_INFO, "Using exact sizes for initial modes\n");
@@ -2404,9 +2462,11 @@ xf86InitialConfiguration(ScrnInfoPtr scrn, Bool canGrow)
                        "Output %s enabled but has no modes\n",
                        config->output[o]->name);
         else
-            xf86DrvMsg(scrn->scrnIndex, X_INFO,
-                       "Output %s using initial mode %s\n",
-                       config->output[o]->name, modes[o]->name);
+            xf86DrvMsg (scrn->scrnIndex, X_INFO,
+                        "Output %s using initial mode %s +%d+%d\n",
+                        config->output[o]->name, modes[o]->name,
+                        config->output[o]->initial_x,
+                        config->output[o]->initial_y);
     }
 
     /*
-- 
1.7.10.4