matroxfb: fix problems with display stability

commit 8c651311a3a08c1e4815de6933e00a760e498dae upstream.

Regression caused in 2.6.23 and then despite repeated requests never fixed
or dealt with (Petr promised to sort it in 2008 but seems to have
forgotten).

Enough is enough - remove the problem line that was added.  If it upsets
someone they've had two years to deal with it and at the very least it'll
rattle their cage and wake them up.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=9709

Signed-off-by: Alan Cox <alan@linux.intel.com>
Reported-by: Damon <account@bugzilla.kernel.org.juxtaposition.net>
Tested-by: Ruud van Melick <rvm1974@raketnet.nl>
Cc: Petr Vandrovec <VANDROVE@vc.cvut.cz>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Paul A. Clarke <pc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/video/matrox/g450_pll.c b/drivers/video/matrox/g450_pll.c
index 09f6e045d5beb19755a3449c711cf746321d9c4e..c15f8a57498ed15e9538c18f78c5ced10c42144e 100644 (file)
--- a/drivers/video/matrox/g450_pll.c
+++ b/drivers/video/matrox/g450_pll.c
@@ -368,7 +368,8 @@ static int __g450_setclk(struct matrox_fb_info *minfo, unsigned int fout,
                                        M1064_XDVICLKCTRL_C1DVICLKEN |
                                        M1064_XDVICLKCTRL_DVILOOPCTL |
                                        M1064_XDVICLKCTRL_P1LOOPBWDTCTL;
-                               matroxfb_DAC_out(minfo, M1064_XDVICLKCTRL, tmp);
+                                /* Setting this breaks PC systems so don't do it */
+                               /* matroxfb_DAC_out(minfo, M1064_XDVICLKCTRL, tmp); */
                                matroxfb_DAC_out(minfo, M1064_XPWRCTRL,
                                                 xpwrctrl);