Default to 32bpp if the console is 8bpp (and we weren't told otherwise)

You can still override this on the command line or in the config file.
Without this we'll come up at 8bpp on matroxfb (and probably others),
which among other things breaks the default desktop since gnome-shell
wants GLX and GLX doesn't support pseudocolor anymore.
Signed-off-by: Adam Jackson <ajax@redhat.com>

src/fbdev.c

@@ -38,6 +38,9 @@
 #include <pciaccess.h>
 #endif
 
+/* for xf86{Depth,FbBpp}. i am a terrible person, and i am sorry. */
+#include "xf86Priv.h"
+
 static Bool debug = 0;
 
 #define TRACE_ENTER(str) \
@@ -427,6 +430,29 @@ FBDevPreInit(ScrnInfoPtr pScrn, int flags)
 	if (!fbdevHWInit(pScrn,NULL,xf86FindOptionValue(fPtr->pEnt->device->options,"fbdev")))
 		return FALSE;
 	default_depth = fbdevHWGetDepth(pScrn,&fbbpp);
+
+	if (default_depth == 8) do {
+	    /* trust the command line */
+	    if (xf86FbBpp > 0 || xf86Depth > 0)
+		break;
+
+	    /* trust the config file's Screen stanza */
+	    if (pScrn->confScreen->defaultfbbpp > 0 ||
+		pScrn->confScreen->defaultdepth > 0)
+		break;
+
+	    /* trust our Device stanza in the config file */
+	    if (xf86FindOption(fPtr->pEnt->device->options, "DefaultDepth") ||
+		xf86FindOption(fPtr->pEnt->device->options, "DefaultFbBpp"))
+		break;
+
+	    /* otherwise, lol no */
+	    xf86DrvMsg(pScrn->scrnIndex, X_INFO,
+		       "Console is 8bpp, defaulting to 32bpp\n");
+	    default_depth = 24;
+	    fbbpp = 32;
+	} while (0);
+
 	if (!xf86SetDepthBpp(pScrn, default_depth, default_depth, fbbpp,
 			     Support24bppFb | Support32bppFb | SupportConvert32to24 | SupportConvert24to32))
 		return FALSE;