Index: xf86DDC.c
===================================================================
RCS file: /cvs/xorg/xserver/xorg/hw/xfree86/ddc/xf86DDC.c,v
retrieving revision 1.7
diff -u -r1.7 xf86DDC.c
--- xf86DDC.c	18 Nov 2005 18:02:24 -0000	1.7
+++ xf86DDC.c	3 Jan 2006 23:21:30 -0000
@@ -119,16 +119,35 @@
     int len
 );
 
+static void 
+EDIDDump(int scrnIndex, xf86MonPtr DDC);
+
+/* Pure for testing/debugging. No user should ever do this. */
+#define HAVEEDIDLOAD 1
+
+#ifdef HAVEEDIDLOAD
+static unsigned char * EDIDLoad(int scrnIndex, char *FileName);
+#endif
+
 typedef enum {
     DDCOPT_NODDC1,
     DDCOPT_NODDC2,
-    DDCOPT_NODDC
+    DDCOPT_NODDC,
+#ifdef HAVEEDIDLOAD
+    DDCOPT_LOAD,
+#endif
+    DDCOPT_DUMP
 } DDCOpts;
 
 static const OptionInfoRec DDCOptions[] = {
     { DDCOPT_NODDC1,	"NoDDC1",	OPTV_BOOLEAN,	{0},	FALSE },
     { DDCOPT_NODDC2,	"NoDDC2",	OPTV_BOOLEAN,	{0},	FALSE },
     { DDCOPT_NODDC,	"NoDDC",	OPTV_BOOLEAN,	{0},	FALSE },
+#ifdef HAVEEDIDLOAD
+    { DDCOPT_LOAD,      "LoadDDC",      OPTV_ANYSTR,    {0},    FALSE },
+#endif
+    { DDCOPT_DUMP,      "DumpDDC",      OPTV_BOOLEAN,   {0},    FALSE },
+      
     { -1,		NULL,		OPTV_NONE,	{0},	FALSE },
 };
 
@@ -152,8 +171,11 @@
     xf86MonPtr tmp = NULL;
     int sigio;
     /* Default DDC and DDC1 to enabled. */
-    Bool noddc = FALSE, noddc1 = FALSE;
+    Bool noddc = FALSE, noddc1 = FALSE, dump;
     OptionInfoPtr options;
+#ifdef HAVEEDIDLOAD
+    char *LoadName = NULL;
+#endif
 
     options = xnfalloc(sizeof(DDCOptions));
     (void)memcpy(options, DDCOptions, sizeof(DDCOptions));
@@ -161,15 +183,28 @@
 
     xf86GetOptValBool(options, DDCOPT_NODDC, &noddc);
     xf86GetOptValBool(options, DDCOPT_NODDC1, &noddc1);
+    dump = xf86ReturnOptValBool(options, DDCOPT_DUMP, FALSE);
+
+#ifdef HAVEEDIDLOAD
+    LoadName = xf86GetOptValString(options, DDCOPT_LOAD);
+#endif
+
     xfree(options);
     
     if (noddc || noddc1)
 	return NULL;
-    
-    sigio = xf86BlockSIGIO();
-    EDID_block = EDIDRead_DDC1(pScrn,DDC1SetSpeed,DDC1Read);
-    xf86UnblockSIGIO(sigio);
 
+#ifdef HAVEEDIDLOAD
+    if (LoadName)
+        EDID_block = EDIDLoad(scrnIndex, LoadName);
+#endif
+
+    if (!EDID_block) {
+        sigio = xf86BlockSIGIO();
+        EDID_block = EDIDRead_DDC1(pScrn,DDC1SetSpeed,DDC1Read);
+        xf86UnblockSIGIO(sigio);
+    }
+    
     if (EDID_block){
 	tmp = xf86InterpretEDID(scrnIndex,EDID_block);
     }
@@ -178,7 +213,11 @@
     if (!tmp)
 	ErrorF("Cannot interpret EDID block\n");
 #endif
-	return tmp;
+
+    if (tmp && dump)
+        EDIDDump(scrnIndex, tmp);
+
+    return tmp;
 }
 
 xf86MonPtr
@@ -189,8 +228,11 @@
     unsigned char *VDIF_Block = NULL;
     xf86MonPtr tmp = NULL;
     /* Default DDC and DDC2 to enabled. */
-    Bool noddc = FALSE, noddc2 = FALSE;
+    Bool noddc = FALSE, noddc2 = FALSE, dump;
     OptionInfoPtr options;
+#ifdef HAVEEDIDLOAD
+    char *LoadName = NULL;
+#endif
 
     options = xnfalloc(sizeof(DDCOptions));
     (void)memcpy(options, DDCOptions, sizeof(DDCOptions));
@@ -198,12 +240,24 @@
 
     xf86GetOptValBool(options, DDCOPT_NODDC, &noddc);
     xf86GetOptValBool(options, DDCOPT_NODDC2, &noddc2);
+    dump = xf86ReturnOptValBool(options, DDCOPT_DUMP, FALSE);
+
+#ifdef HAVEEDIDLOAD
+    LoadName = xf86GetOptValString(options, DDCOPT_LOAD);
+#endif
+
     xfree(options);
     
     if (noddc || noddc2)
 	return NULL;
 
-    EDID_block = EDID1Read_DDC2(scrnIndex,pBus);
+#ifdef HAVEEDIDLOAD
+    if (LoadName)
+        EDID_block = EDIDLoad(scrnIndex, LoadName);
+#endif
+
+    if (!EDID_block)
+        EDID_block = EDID1Read_DDC2(scrnIndex,pBus);
 
     if (EDID_block){
 	tmp = xf86InterpretEDID(scrnIndex,EDID_block);
@@ -224,7 +278,10 @@
             VDIFRead(scrnIndex, pBus, EDID1_LEN * (tmp->no_sections + 1));    
         tmp->vdif = xf86InterpretVdif(VDIF_Block);
     }
-    
+
+    if (tmp && dump)
+        EDIDDump(scrnIndex, tmp);
+
     return tmp;
 }
 
@@ -385,3 +442,58 @@
     xfree(R_Buffer);
     return NULL;
 }
+
+/*
+ * Provide a means to dump edid blocks for debugging use.
+ */
+static void 
+EDIDDump(int scrnIndex, xf86MonPtr DDC)
+{
+    XF86FILE *EdidFile = NULL;
+    char FileName[20];
+
+    xf86snprintf(FileName, 20, "/tmp/%s-%04X.edid", DDC->vendor.name,
+                 DDC->vendor.prod_id);
+    
+    xf86DrvMsg(scrnIndex, X_INFO, "Dumping EDID block to %s\n", FileName);
+
+    EdidFile = xf86fopen(FileName, "w");
+    if (!EdidFile) {
+        xf86DrvMsg(scrnIndex, X_WARNING, "Failed to open %s\n", FileName);
+        return;
+    }
+
+    xf86fwrite(DDC->rawData, EDID1_LEN, 1, EdidFile);
+    xf86fclose(EdidFile);
+}
+
+#ifdef HAVEEDIDLOAD
+/*
+ * This one allows devs to easily test different edid blocks.
+ */
+static unsigned char *
+EDIDLoad(int scrnIndex, char *FileName)
+{
+    XF86FILE *EdidFile = NULL;
+    unsigned char *Edid = NULL;
+    
+    xf86DrvMsg(scrnIndex, X_WARNING, "Loading %s for DDC information.\n", FileName);
+    xf86DrvMsg(scrnIndex, X_WARNING, "This should only be used for testing!\n");
+
+    EdidFile = xf86fopen(FileName, "r");
+    if (!EdidFile) {
+        xf86DrvMsg(scrnIndex, X_WARNING, "Failed to open %s\n", FileName);
+        return NULL;
+    }
+
+    Edid = xnfalloc(EDID1_LEN);
+
+    if (EDID1_LEN != xf86fread(Edid, 1, EDID1_LEN, EdidFile)) {
+        xf86DrvMsg(scrnIndex, X_WARNING, "Failed to read from %s\n", FileName);
+        xfree(Edid);
+        return NULL;
+    }
+
+    return Edid;
+}
+#endif