[RFC 12/15] drm/exynos/dpi: use common of_graph functions

[Andrzej Hajda]

The patch removes private of_graph functions and uses common ones.

Signed-off-by: Andrzej Hajda <a.hajda at samsung.com>
---
 drivers/gpu/drm/exynos/exynos_drm_dpi.c | 117 +++++++-------------------------
 1 file changed, 24 insertions(+), 93 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_dpi.c b/drivers/gpu/drm/exynos/exynos_drm_dpi.c
index 37678cf..91a29e1 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_dpi.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_dpi.c
@@ -14,6 +14,7 @@
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_panel.h>
 
+#include <linux/of_graph.h>
 #include <linux/regulator/consumer.h>
 
 #include <video/of_videomode.h>
@@ -21,6 +22,15 @@
 
 #include "exynos_drm_drv.h"
 
+/* possible of_graph port nodes used by device */
+enum {
+	FIMD_PORT_IN0,
+	FIMD_PORT_IN1,
+	FIMD_PORT_IN2,
+	FIMD_PORT_RGB,
+	FIMD_PORT_WRB,
+};
+
 struct exynos_dpi {
 	struct exynos_drm_display display;
 	struct device *dev;
@@ -171,102 +181,12 @@ static struct exynos_drm_display_ops exynos_dpi_display_ops = {
 	.dpms = exynos_dpi_dpms
 };
 
-/* of_* functions will be removed after merge of of_graph patches */
-static struct device_node *
-of_get_child_by_name_reg(struct device_node *parent, const char *name, u32 reg)
-{
-	struct device_node *np;
-
-	for_each_child_of_node(parent, np) {
-		u32 r;
-
-		if (!np->name || of_node_cmp(np->name, name))
-			continue;
-
-		if (of_property_read_u32(np, "reg", &r) < 0)
-			r = 0;
-
-		if (reg == r)
-			break;
-	}
-
-	return np;
-}
-
-static struct device_node *of_graph_get_port_by_reg(struct device_node *parent,
-						    u32 reg)
-{
-	struct device_node *ports, *port;
-
-	ports = of_get_child_by_name(parent, "ports");
-	if (ports)
-		parent = ports;
-
-	port = of_get_child_by_name_reg(parent, "port", reg);
-
-	of_node_put(ports);
-
-	return port;
-}
-
-static struct device_node *
-of_graph_get_endpoint_by_reg(struct device_node *port, u32 reg)
-{
-	return of_get_child_by_name_reg(port, "endpoint", reg);
-}
-
-static struct device_node *
-of_graph_get_remote_port_parent(const struct device_node *node)
-{
-	struct device_node *np;
-	unsigned int depth;
-
-	np = of_parse_phandle(node, "remote-endpoint", 0);
-
-	/* Walk 3 levels up only if there is 'ports' node. */
-	for (depth = 3; depth && np; depth--) {
-		np = of_get_next_parent(np);
-		if (depth == 2 && of_node_cmp(np->name, "ports"))
-			break;
-	}
-	return np;
-}
-
-enum {
-	FIMD_PORT_IN0,
-	FIMD_PORT_IN1,
-	FIMD_PORT_IN2,
-	FIMD_PORT_RGB,
-	FIMD_PORT_WRB,
-};
-
-static struct device_node *exynos_dpi_of_find_panel_node(struct device *dev)
-{
-	struct device_node *np, *ep;
-
-	np = of_graph_get_port_by_reg(dev->of_node, FIMD_PORT_RGB);
-	if (!np)
-		return NULL;
-
-	ep = of_graph_get_endpoint_by_reg(np, 0);
-	of_node_put(np);
-	if (!ep)
-		return NULL;
-
-	np = of_graph_get_remote_port_parent(ep);
-	of_node_put(ep);
-
-	return np;
-}
-
 static int exynos_dpi_parse_dt(struct exynos_dpi *ctx)
 {
 	struct device *dev = ctx->dev;
 	struct device_node *dn = dev->of_node;
 	struct device_node *np;
 
-	ctx->panel_node = exynos_dpi_of_find_panel_node(dev);
-
 	np = of_get_child_by_name(dn, "display-timings");
 	if (np) {
 		struct videomode *vm;
@@ -289,10 +209,21 @@ static int exynos_dpi_parse_dt(struct exynos_dpi *ctx)
 		return 0;
 	}
 
-	if (!ctx->panel_node)
-		return -EINVAL;
+	np = NULL;
+	while ((np = of_graph_get_next_endpoint(dev->of_node, np))) {
+		struct of_endpoint ep;
 
-	return 0;
+		of_graph_parse_endpoint(np, &ep);
+		if (ep.port != FIMD_PORT_RGB)
+			continue;
+
+		ctx->panel_node = of_graph_get_remote_port_parent(np);
+		of_node_put(np);
+
+		return ctx->panel_node ? 0 : -EINVAL;
+	}
+
+	return -EINVAL;
 }
 
 struct exynos_drm_display *exynos_dpi_probe(struct device *dev)
-- 
1.9.1