drm/radeon/kms/atom: pull misc mode info for lvds from bios tables

sync polarity, etc.  This will likely fix LVDS problems
on some laptops.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/radeon_atombios.c

@@ -910,7 +910,7 @@ struct radeon_encoder_atom_dig *radeon_atombios_get_lvds_info(struct
 	struct radeon_device *rdev = dev->dev_private;
 	struct radeon_mode_info *mode_info = &rdev->mode_info;
 	int index = GetIndexIntoMasterTable(DATA, LVDS_Info);
-	uint16_t data_offset;
+	uint16_t data_offset, misc;
 	union lvds_info *lvds_info;
 	uint8_t frev, crev;
 	struct radeon_encoder_atom_dig *lvds = NULL;
@@ -949,6 +949,19 @@ struct radeon_encoder_atom_dig *radeon_atombios_get_lvds_info(struct
 		lvds->panel_pwr_delay =
 		    le16_to_cpu(lvds_info->info.usOffDelayInMs);
 		lvds->lvds_misc = lvds_info->info.ucLVDS_Misc;
+
+		misc = le16_to_cpu(lvds_info->info.sLCDTiming.susModeMiscInfo.usAccess);
+		if (misc & ATOM_VSYNC_POLARITY)
+			lvds->native_mode.flags |= DRM_MODE_FLAG_NVSYNC;
+		if (misc & ATOM_HSYNC_POLARITY)
+			lvds->native_mode.flags |= DRM_MODE_FLAG_NHSYNC;
+		if (misc & ATOM_COMPOSITESYNC)
+			lvds->native_mode.flags |= DRM_MODE_FLAG_CSYNC;
+		if (misc & ATOM_INTERLACE)
+			lvds->native_mode.flags |= DRM_MODE_FLAG_INTERLACE;
+		if (misc & ATOM_DOUBLE_CLOCK_MODE)
+			lvds->native_mode.flags |= DRM_MODE_FLAG_DBLSCAN;
+
 		/* set crtc values */
 		drm_mode_set_crtcinfo(&lvds->native_mode, CRTC_INTERLACE_HALVE_V);