[PATCH] MGA DDX: default to use EXA if XAA is unavailable

[Matthew Rezny]

The MGA DDX still defaults to XAA because the EXA support is buggy on some 
hardware. Unfortunately, XAA support is gone from newer versions of the 
xserver. If only EXA is present, that is usually better than no accel, so use 
it by default. Patch to default to EXA when lacking XAA inspired by r128.

--- src/mga_driver.c.orig       2015-05-24 00:21:50 UTC
+++ src/mga_driver.c
@@ -1911,7 +1911,11 @@ MGAPreInit(ScrnInfoPtr pScrn, int flags)
        char *s = xf86GetOptValString(pMga->Options, OPTION_ACCELMETHOD);
 #endif
        pMga->NoAccel = FALSE;
+#if defined(USE_EXA) && !defined(USE_XAA)
+       pMga->Exa = TRUE;
+#else
        pMga->Exa = FALSE;
+#endif
 #ifdef USE_EXA
        if (!xf86NameCmp(s, "EXA")) {
            pMga->Exa = TRUE;