diff --git a/drivers/video/fbdev/msm/mdss_mdp_ctl.c b/drivers/video/fbdev/msm/mdss_mdp_ctl.c
index 0da462394ab8..efd681a5d954 100644
--- a/drivers/video/fbdev/msm/mdss_mdp_ctl.c
+++ b/drivers/video/fbdev/msm/mdss_mdp_ctl.c
@@ -2513,6 +2513,7 @@ struct mdss_mdp_mixer *mdss_mdp_mixer_alloc(
 	u32 nmixers_wb;
 	u32 i;
 	u32 nmixers;
+	u32 nmixers_active;
 	struct mdss_mdp_mixer *mixer_pool = NULL;
 
 	if (!ctl || !ctl->mdata)
@@ -2526,10 +2527,21 @@ struct mdss_mdp_mixer *mdss_mdp_mixer_alloc(
 	case MDSS_MDP_MIXER_TYPE_INTF:
 		mixer_pool = ctl->mdata->mixer_intf;
 		nmixers = nmixers_intf;
+		nmixers_active = nmixers;
+
+		for (i = 0; i < nmixers; i++) {
+			mixer = mixer_pool + i;
+			if (mixer->ref_cnt)
+				nmixers_active--;
+		}
+		mixer = NULL;
 
 		/*
 		 * try to reserve first layer mixer for write back if
-		 * assertive display needs to be supported through wfd
+		 * assertive display needs to be supported through wfd.
+		 * For external displays(pluggable) and writeback avoid
+		 * allocating mixers LM0 and LM1 which are allocated
+		 * to primary display first.
 		 */
 		if (ctl->mdata->has_wb_ad && ctl->intf_num &&
 			((ctl->panel_data->panel_info.type != MIPI_CMD_PANEL) ||
@@ -2541,6 +2553,10 @@ struct mdss_mdp_mixer *mdss_mdp_mixer_alloc(
 			&& (ctl->mdata->ndspp < nmixers)) {
 			mixer_pool += ctl->mdata->ndspp;
 			nmixers -= ctl->mdata->ndspp;
+		} else if ((ctl->panel_data->panel_info.is_pluggable) &&
+				nmixers_active) {
+			mixer_pool += ctl->mdata->ndspp;
+			nmixers -= ctl->mdata->ndspp;
 		}
 		break;