Video overlay gamma bounds checking must be done bytewise.

Also, pend bound computations to register writes to allow
updates to individual values that are 'out of spec' so
the client can update multiple values.

1 files changed, 42 insertions, 19 deletions

diff --git a/src/i830_video.c b/src/i830_video.c
index 0ae68607..a608a7e3 100644
--- a/src/i830_video.c
+++ b/src/i830_video.c
@@ -592,18 +592,53 @@ I830SetOneLineModeRatio(ScrnInfoPtr pScrn)
       pPriv->oneLineMode = FALSE;
 }
 
+static CARD32 I830BoundGammaElt (CARD32 elt, CARD32 eltPrev)
+{
+   elt &= 0xff;
+   eltPrev &= 0xff;
+   if (elt < eltPrev)
+      elt = eltPrev;
+   else if ((elt - eltPrev) > 0x7e)
+      elt = eltPrev + 0x7e;
+   return elt;
+}
+
+static CARD32 I830BoundGamma (CARD32 gamma, CARD32 gammaPrev)
+{
+   return (I830BoundGammaElt (gamma >> 24, gammaPrev >> 24) << 24 |
+	   I830BoundGammaElt (gamma >> 16, gammaPrev >> 16) << 16 |
+	   I830BoundGammaElt (gamma >>  8, gammaPrev >>  8) <<  8 |
+	   I830BoundGammaElt (gamma      , gammaPrev      ));
+}
+
 static void
 I830UpdateGamma(ScrnInfoPtr pScrn)
 {
    I830Ptr pI830 = I830PTR(pScrn);
    I830PortPrivPtr pPriv = pI830->adaptor->pPortPrivates[0].ptr;
-
-   OUTREG(OGAMC5, pPriv->gamma5);
-   OUTREG(OGAMC4, pPriv->gamma4);
-   OUTREG(OGAMC3, pPriv->gamma3);
-   OUTREG(OGAMC2, pPriv->gamma2);
-   OUTREG(OGAMC1, pPriv->gamma1);
-   OUTREG(OGAMC0, pPriv->gamma0);
+   CARD32   gamma0 = pPriv->gamma0;
+   CARD32   gamma1 = pPriv->gamma1;
+   CARD32   gamma2 = pPriv->gamma2;
+   CARD32   gamma3 = pPriv->gamma3;
+   CARD32   gamma4 = pPriv->gamma4;
+   CARD32   gamma5 = pPriv->gamma5;
+
+   ErrorF ("Original gamma: 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
+	   gamma0, gamma1, gamma2, gamma3, gamma4, gamma5);
+   gamma1 = I830BoundGamma (gamma1, gamma0);
+   gamma2 = I830BoundGamma (gamma2, gamma1);
+   gamma3 = I830BoundGamma (gamma3, gamma2);
+   gamma4 = I830BoundGamma (gamma4, gamma3);
+   gamma5 = I830BoundGamma (gamma5, gamma4);
+   ErrorF ("Bounded  gamma: 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
+	   gamma0, gamma1, gamma2, gamma3, gamma4, gamma5);
+
+   OUTREG(OGAMC5, gamma5);
+   OUTREG(OGAMC4, gamma4);
+   OUTREG(OGAMC3, gamma3);
+   OUTREG(OGAMC2, gamma2);
+   OUTREG(OGAMC1, gamma1);
+   OUTREG(OGAMC0, gamma0);
 }
 
 static XF86VideoAdaptorPtr
@@ -849,28 +884,16 @@ I830SetPortAttribute(ScrnInfoPtr pScrn,
 #endif
    } else if (attribute == xvGamma0 && (IS_I9XX(pI830))) {
       pPriv->gamma0 = value; 
-      if (pPriv->gamma1 - pPriv->gamma0 > 0x7d)
-         pPriv->gamma1 = pPriv->gamma0 + 0x7d;
    } else if (attribute == xvGamma1 && (IS_I9XX(pI830))) {
       pPriv->gamma1 = value;
-      if (pPriv->gamma1 - pPriv->gamma0 > 0x7d)
-        pPriv->gamma0 = pPriv->gamma1 - 0x7d;
    } else if (attribute == xvGamma2 && (IS_I9XX(pI830))) {
       pPriv->gamma2 = value;
-      if (pPriv->gamma3 - pPriv->gamma2 > 0x7d)
-         pPriv->gamma3 = pPriv->gamma2 + 0x7d;
    } else if (attribute == xvGamma3 && (IS_I9XX(pI830))) {
       pPriv->gamma3 = value;
-      if (pPriv->gamma3 - pPriv->gamma2 > 0x7d)
-         pPriv->gamma2 = pPriv->gamma3 - 0x7d;
    } else if (attribute == xvGamma4 && (IS_I9XX(pI830))) {
       pPriv->gamma4 = value;
-      if (pPriv->gamma5 - pPriv->gamma4 > 0x7d)
-         pPriv->gamma5 = pPriv->gamma4 + 0x7d;
    } else if (attribute == xvGamma5 && (IS_I9XX(pI830))) {
       pPriv->gamma5 = value;
-      if (pPriv->gamma5 - pPriv->gamma4 > 0x7d)
-         pPriv->gamma4 = pPriv->gamma5 - 0x7d;
    } else if (attribute == xvColorKey) {
       pPriv->colorKey = value;
       switch (pScrn->depth) {