lxfb: set the H- and V-SYNC polarity of the flatpanel output

Fixup for the flatpanel output.  The geode_modedb attribute flags are used
to set the SYNC polarity of the flatpanel.  Without this patch our
flatpanel registers stayed unconfigured, so we just saw garbage output.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Cc: Andres Salomon <dilinger@collabora.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/geode/lxfb.h

@@ -365,6 +365,8 @@ enum fp_registers {
 	FP_CRC, /* 0x458 */
 };
 
+#define FP_PT2_HSP			(1 << 22)
+#define FP_PT2_VSP			(1 << 23)
 #define FP_PT2_SCRC			(1 << 27)	/* shfclk free */
 
 #define FP_PM_P				(1 << 24)	/* panel power ctl */

drivers/video/geode/lxfb_ops.c

@@ -274,7 +274,15 @@ static void lx_graphics_enable(struct fb_info *info)
 		u32 msrlo, msrhi;
 
 		write_fp(par, FP_PT1, 0);
-		write_fp(par, FP_PT2, FP_PT2_SCRC);
+		temp = FP_PT2_SCRC;
+
+		if (info->var.sync & FB_SYNC_HOR_HIGH_ACT)
+			temp |= FP_PT2_HSP;
+
+		if (info->var.sync & FB_SYNC_VERT_HIGH_ACT)
+			temp |= FP_PT2_VSP;
+
+		write_fp(par, FP_PT2, temp);
 		write_fp(par, FP_DFC, FP_DFC_BC);
 
 		msrlo = MSR_LX_MSR_PADSEL_TFT_SEL_LOW;