[media] media: davinci: vpif: add check for NULL handler

for da850/omap-l138, there is no need to setup_input_channel_mode()
and set_clock(), to avoid adding dummy code in board file just returning
zero add a check in the driver itself to call the handler only if its
not NULL.

Signed-off-by: Lad, Prabhakar <prabhakar.lad@ti.com>
Signed-off-by: Manjunath Hadli <manjunath.hadli@ti.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/platform/davinci/vpif_capture.c

@@ -311,12 +311,13 @@ static int vpif_start_streaming(struct vb2_queue *vq, unsigned int count)
 	}
 
 	/* configure 1 or 2 channel mode */
-	ret = vpif_config_data->setup_input_channel_mode
-					(vpif->std_info.ycmux_mode);
-
-	if (ret < 0) {
-		vpif_dbg(1, debug, "can't set vpif channel mode\n");
-		return ret;
+	if (vpif_config_data->setup_input_channel_mode) {
+		ret = vpif_config_data->
+			setup_input_channel_mode(vpif->std_info.ycmux_mode);
+		if (ret < 0) {
+			vpif_dbg(1, debug, "can't set vpif channel mode\n");
+			return ret;
+		}
 	}
 
 	/* Call vpif_set_params function to set the parameters and addresses */

drivers/media/platform/davinci/vpif_display.c

@@ -280,12 +280,13 @@ static int vpif_start_streaming(struct vb2_queue *vq, unsigned int count)
 	}
 
 	/* clock settings */
-	ret =
-	    vpif_config_data->set_clock(ch->vpifparams.std_info.ycmux_mode,
-					ch->vpifparams.std_info.hd_sd);
-	if (ret < 0) {
-		vpif_err("can't set clock\n");
-		return ret;
+	if (vpif_config_data->set_clock) {
+		ret = vpif_config_data->set_clock(ch->vpifparams.std_info.
+		ycmux_mode, ch->vpifparams.std_info.hd_sd);
+		if (ret < 0) {
+			vpif_err("can't set clock\n");
+			return ret;
+		}
 	}
 
 	/* set the parameters and addresses */