drm/radeon/kms: minor fixes for eDP with LCD* device tags (v2)

Some systems have LCD* rather than DFP* device tags in the bios
for eDP connectors; notably the new apple iMac. This fixes
things up so eDP connectors with either tag will work.

v2: fix typo

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c
index 56107b3..fd4ef6d 100644
--- a/drivers/gpu/drm/radeon/atombios_crtc.c
+++ b/drivers/gpu/drm/radeon/atombios_crtc.c
@@ -581,11 +581,16 @@
 					}
 				} else if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT)) {
 					/* may want to enable SS on DP/eDP eventually */
-					args.v3.sInput.ucDispPllConfig |=
-						DISPPLL_CONFIG_SS_ENABLE;
-					if (mode->clock > 165000)
+					/*args.v3.sInput.ucDispPllConfig |=
+						DISPPLL_CONFIG_SS_ENABLE;*/
+					if (encoder_mode == ATOM_ENCODER_MODE_DP)
 						args.v3.sInput.ucDispPllConfig |=
-							DISPPLL_CONFIG_DUAL_LINK;
+							DISPPLL_CONFIG_COHERENT_MODE;
+					else {
+						if (mode->clock > 165000)
+							args.v3.sInput.ucDispPllConfig |=
+								DISPPLL_CONFIG_DUAL_LINK;
+					}
 				}
 				atom_execute_table(rdev->mode_info.atom_context,
 						   index, (uint32_t *)&args);