xfree86: Hook up colormaps and RandR 1.2 gamma code v6

Instead of breaking the former when the driver supports the latter,
hook them up so that the hardware LUTs reflect the combination of the
current colourmap and gamma states. I.e. combine the colourmap, the
global gamma value/ramp and the RandR 1.2 per-CRTC gamma ramps into one
combined LUT per CRTC.

Fixes e.g. gamma sliders not working in games.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=27222

v2:
* Initialize palette_size and palette struct members, fixes crash on
  server startup.
v3:
* Free randrp->palette in xf86RandR12CloseScreen, fixes memory leak.
v4:
* Call CMapUnwrapScreen if xf86RandR12InitGamma fails (Emil Velikov).
* Still allow xf86HandleColormaps to be called with a NULL loadPalette
  parameter in the xf86_crtc_supports_gamma case.
v5:
* Clean up inner loops in xf86RandR12CrtcComputeGamma (Keith Packard)
* Move palette update out of per-CRTC loop in xf86RandR12LoadPalette
  (Keith Packard)
v6:
* Handle reallocarray failure in xf86RandR12LoadPalette (Keith Packard)

Reviewed-by: Keith Packard <keithp@keithp.com>

2 files changed, 13 insertions, 54 deletions

diff --git a/hw/xfree86/common/xf86Helper.c b/hw/xfree86/common/xf86Helper.c
index bceb0174b..6f3a6086b 100644
--- a/hw/xfree86/common/xf86Helper.c
+++ b/hw/xfree86/common/xf86Helper.c
@@ -54,7 +54,6 @@
 #include "xf86Xinput.h"
 #include "xf86InPriv.h"
 #include "mivalidate.h"
-#include "xf86Crtc.h"
 
 /* For xf86GetClocks */
 #if defined(CSRG_BASED) || defined(__GNU__)
@@ -908,11 +907,7 @@ xf86SetGamma(ScrnInfoPtr scrp, Gamma gamma)
         scrp->gamma.green = 1.0;
         scrp->gamma.blue = 1.0;
     }
-    /* Pretend we succeeded if we support better a gamma system.
-     * This avoids a confusing message.
-     */
-    if (xf86_crtc_supports_gamma(scrp))
-        return TRUE;
+
     xf86DrvMsg(scrp->scrnIndex, from,
                "Using gamma correction (%.1f, %.1f, %.1f)\n",
                scrp->gamma.red, scrp->gamma.green, scrp->gamma.blue);
diff --git a/hw/xfree86/common/xf86cmap.c b/hw/xfree86/common/xf86cmap.c
index ba0b277a1..8588c9fba 100644
--- a/hw/xfree86/common/xf86cmap.c
+++ b/hw/xfree86/common/xf86cmap.c
@@ -49,6 +49,7 @@
 #include "xf86_OSproc.h"
 #include "xf86str.h"
 #include "micmap.h"
+#include "xf86RandR12.h"
 #include "xf86Crtc.h"
 
 #ifdef XFreeXDGA
@@ -132,9 +133,6 @@ static void CMapUnwrapScreen(ScreenPtr pScreen);
 Bool
 xf86ColormapAllocatePrivates(ScrnInfoPtr pScrn)
 {
-    /* If we support a better colormap system, then pretend we succeeded. */
-    if (xf86_crtc_supports_gamma(pScrn))
-        return TRUE;
     if (!dixRegisterPrivateKey(&CMapScreenKeyRec, PRIVATE_SCREEN, 0))
         return FALSE;
 
@@ -157,11 +155,8 @@ xf86HandleColormaps(ScreenPtr pScreen,
     int *indices;
     int elements;
 
-    /* If we support a better colormap system, then pretend we succeeded. */
-    if (xf86_crtc_supports_gamma(pScrn))
-        return TRUE;
-
-    if (!maxColors || !sigRGBbits || !loadPalette)
+    if (!maxColors || !sigRGBbits ||
+        (!loadPalette && !xf86_crtc_supports_gamma(pScrn)))
         return FALSE;
 
     elements = 1 << sigRGBbits;
@@ -230,6 +225,15 @@ xf86HandleColormaps(ScreenPtr pScreen,
         return FALSE;
     }
 
+    if (xf86_crtc_supports_gamma(pScrn)) {
+        pScrn->LoadPalette = xf86RandR12LoadPalette;
+
+        if (!xf86RandR12InitGamma(pScrn, elements)) {
+            CMapUnwrapScreen(pScreen);
+            return FALSE;
+        }
+    }
+
     /* Force the initial map to be loaded */
     SetInstalledmiColormap(pScreen, NULL);
     CMapInstallColormap(pDefMap);
@@ -1005,19 +1009,6 @@ xf86ChangeGammaRamp(ScreenPtr pScreen,
     CMapScreenPtr pScreenPriv;
     CMapLinkPtr pLink;
 
-    if (xf86_crtc_supports_gamma(pScrn)) {
-        RRCrtcPtr crtc = xf86CompatRRCrtc(pScrn);
-
-        if (crtc) {
-            if (crtc->gammaSize != size)
-                return BadValue;
-
-            RRCrtcGammaSet(crtc, red, green, blue);
-
-            return Success;
-        }
-    }
-
     if (!CMapScreenKeyRegistered)
         return BadImplementation;
 
@@ -1077,16 +1068,8 @@ xf86ChangeGammaRamp(ScreenPtr pScreen,
 int
 xf86GetGammaRampSize(ScreenPtr pScreen)
 {
-    ScrnInfoPtr pScrn = xf86ScreenToScrn(pScreen);
     CMapScreenPtr pScreenPriv;
 
-    if (xf86_crtc_supports_gamma(pScrn)) {
-        RRCrtcPtr crtc = xf86CompatRRCrtc(pScrn);
-
-        if (crtc)
-            return crtc->gammaSize;
-    }
-
     if (!CMapScreenKeyRegistered)
         return 0;
 
@@ -1104,29 +1087,10 @@ xf86GetGammaRamp(ScreenPtr pScreen,
                  unsigned short *red,
                  unsigned short *green, unsigned short *blue)
 {
-    ScrnInfoPtr pScrn = xf86ScreenToScrn(pScreen);
     CMapScreenPtr pScreenPriv;
     LOCO *entry;
     int shift, sigbits;
 
-    if (xf86_crtc_supports_gamma(pScrn)) {
-        RRCrtcPtr crtc = xf86CompatRRCrtc(pScrn);
-
-        if (crtc) {
-            if (crtc->gammaSize < size)
-                return BadValue;
-
-            if (!RRCrtcGammaGet(crtc))
-                return BadImplementation;
-
-            memcpy(red, crtc->gammaRed, size * sizeof(*red));
-            memcpy(green, crtc->gammaGreen, size * sizeof(*green));
-            memcpy(blue, crtc->gammaBlue, size * sizeof(*blue));
-
-            return Success;
-        }
-    }
-
     if (!CMapScreenKeyRegistered)
         return BadImplementation;