media: qcom: camss: Restructure camss_link_entities

Refactor the camss_link_entities function by breaking it down into
three distinct functions. Each function will handle the linking of
a specific entity separately.
SC7280 and later targets mandates for 1:1 linking for csid -> vfe.
i.e. csid0 can be mapped to vfe0 only.

Signed-off-by: Suresh Vankadara <quic_svankada@quicinc.com>
Signed-off-by: Trishansh Bhardwaj <quic_tbhardwa@quicinc.com>
Signed-off-by: Vikram Sharma <quic_vikramsa@quicinc.com>
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>

drivers/media/platform/qcom/camss/camss.c

@@ -1994,7 +1994,6 @@ static int camss_init_subdevices(struct camss *camss)
 }
 
 /*
- * camss_link_entities - Register subdev nodes and create links
  * camss_link_err - print error in case link creation fails
  * @src_name: name for source of the link
  * @sink_name: name for sink of the link
@@ -2012,14 +2011,64 @@ inline void camss_link_err(struct camss *camss,
 }
 
 /*
- * camss_link_entities - Register subdev nodes and create links
+ * camss_link_entities_csid - Register subdev nodes and create links
  * @camss: CAMSS device
  *
  * Return 0 on success or a negative error code on failure
  */
-static int camss_link_entities(struct camss *camss)
+static int camss_link_entities_csid(struct camss *camss)
 {
-	int i, j, k;
+	struct media_entity *src_entity;
+	struct media_entity *sink_entity;
+	int ret, line_num;
+	u16 sink_pad;
+	u16 src_pad;
+	int i, j;
+
+	for (i = 0; i < camss->res->csid_num; i++) {
+		if (camss->ispif)
+			line_num = camss->ispif->line_num;
+		else
+			line_num = camss->vfe[i].res->line_num;
+
+		src_entity = &camss->csid[i].subdev.entity;
+		for (j = 0; j < line_num; j++) {
+			if (camss->ispif) {
+				sink_entity = &camss->ispif->line[j].subdev.entity;
+				src_pad = MSM_CSID_PAD_SRC;
+				sink_pad = MSM_ISPIF_PAD_SINK;
+			} else {
+				sink_entity = &camss->vfe[i].line[j].subdev.entity;
+				src_pad = MSM_CSID_PAD_FIRST_SRC + j;
+				sink_pad = MSM_VFE_PAD_SINK;
+			}
+
+			ret = media_create_pad_link(src_entity,
+						    src_pad,
+						    sink_entity,
+						    sink_pad,
+						    0);
+			if (ret < 0) {
+				camss_link_err(camss, src_entity->name,
+					       sink_entity->name,
+					       ret);
+				return ret;
+			}
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * camss_link_entities_csiphy - Register subdev nodes and create links
+ * @camss: CAMSS device
+ *
+ * Return 0 on success or a negative error code on failure
+ */
+static int camss_link_entities_csiphy(struct camss *camss)
+{
+	int i, j;
 	int ret;
 
 	for (i = 0; i < camss->res->csiphy_num; i++) {
@@ -2039,66 +2088,68 @@ static int camss_link_entities(struct camss *camss)
 		}
 	}
 
-	if (camss->ispif) {
+	return 0;
-		for (i = 0; i < camss->res->csid_num; i++) {
+}
-			for (j = 0; j < camss->ispif->line_num; j++) {
+
-				ret = media_create_pad_link(&camss->csid[i].subdev.entity,
+/*
-							    MSM_CSID_PAD_SRC,
+ * camss_link_entities_ispif - Register subdev nodes and create links
-							    &camss->ispif->line[j].subdev.entity,
+ * @camss: CAMSS device
-							    MSM_ISPIF_PAD_SINK,
+ *
+ * Return 0 on success or a negative error code on failure
+ */
+static int camss_link_entities_ispif(struct camss *camss)
+{
+	int i, j, k;
+	int ret;
+
+	for (i = 0; i < camss->ispif->line_num; i++) {
+		for (k = 0; k < camss->res->vfe_num; k++) {
+			for (j = 0; j < camss->vfe[k].res->line_num; j++) {
+				struct v4l2_subdev *ispif = &camss->ispif->line[i].subdev;
+				struct v4l2_subdev *vfe = &camss->vfe[k].line[j].subdev;
+
+				ret = media_create_pad_link(&ispif->entity,
+							    MSM_ISPIF_PAD_SRC,
+							    &vfe->entity,
+							    MSM_VFE_PAD_SINK,
 							    0);
 				if (ret < 0) {
-					camss_link_err(camss,
+					camss_link_err(camss, ispif->entity.name,
-						       camss->csid[i].subdev.entity.name,
+						       vfe->entity.name,
-						       camss->ispif->line[j].subdev.entity.name,
 						       ret);
 					return ret;
 				}
 			}
 		}
-
-		for (i = 0; i < camss->ispif->line_num; i++)
-			for (k = 0; k < camss->res->vfe_num; k++)
-				for (j = 0; j < camss->vfe[k].res->line_num; j++) {
-					struct v4l2_subdev *ispif = &camss->ispif->line[i].subdev;
-					struct v4l2_subdev *vfe = &camss->vfe[k].line[j].subdev;
-
-					ret = media_create_pad_link(&ispif->entity,
-								    MSM_ISPIF_PAD_SRC,
-								    &vfe->entity,
-								    MSM_VFE_PAD_SINK,
-								    0);
-					if (ret < 0) {
-						camss_link_err(camss, ispif->entity.name,
-							       vfe->entity.name,
-							       ret);
-						return ret;
-					}
-				}
-	} else {
-		for (i = 0; i < camss->res->csid_num; i++)
-			for (k = 0; k < camss->res->vfe_num; k++)
-				for (j = 0; j < camss->vfe[k].res->line_num; j++) {
-					struct v4l2_subdev *csid = &camss->csid[i].subdev;
-					struct v4l2_subdev *vfe = &camss->vfe[k].line[j].subdev;
-
-					ret = media_create_pad_link(&csid->entity,
-								    MSM_CSID_PAD_FIRST_SRC + j,
-								    &vfe->entity,
-								    MSM_VFE_PAD_SINK,
-								    0);
-					if (ret < 0) {
-						camss_link_err(camss, csid->entity.name,
-							       vfe->entity.name,
-							       ret);
-						return ret;
-					}
-				}
 	}
 
 	return 0;
 }
 
+/*
+ * camss_link_entities - Register subdev nodes and create links
+ * @camss: CAMSS device
+ *
+ * Return 0 on success or a negative error code on failure
+ */
+static int camss_link_entities(struct camss *camss)
+{
+	int ret;
+
+	ret = camss_link_entities_csiphy(camss);
+	if (ret < 0)
+		return ret;
+
+	ret = camss_link_entities_csid(camss);
+	if (ret < 0)
+		return ret;
+
+	if (camss->ispif)
+		ret = camss_link_entities_ispif(camss);
+
+	return ret;
+}
+
 /*
  * camss_register_entities - Register subdev nodes and create links
  * @camss: CAMSS device