of: add function to read a file as unflattened device tree

There are several places in the tree that read in a dtb file
and unflatten it. Add a of_read_file() helper function for that
and use it where appropriately.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

5 files changed, 15 insertions, 70 deletions

diff --git a/commands/of_diff.c b/commands/of_diff.c
index 6a78263200..19a4a26d20 100644
--- a/commands/of_diff.c
+++ b/commands/of_diff.c
@@ -16,9 +16,6 @@
 static struct device_node *get_tree(const char *filename, struct device_node *root)
 {
 	struct device_node *node;
-	void *fdt;
-	size_t size;
-	int ret;
 
 	if (!strcmp(filename, "-")) {
 		node = of_get_root_node();
@@ -40,15 +37,7 @@ static struct device_node *get_tree(const char *filename, struct device_node *ro
 		return node;
 	}
 
-	ret = read_file_2(filename, &size, &fdt, FILESIZE_MAX);
-	if (ret)
-		return ERR_PTR(ret);
-
-	node = of_unflatten_dtb(fdt, size);
-
-	free(fdt);
-
-	return node;
+	return of_read_file(filename);
 }
 
 static int do_of_diff(int argc, char *argv[])
diff --git a/commands/of_display_timings.c b/commands/of_display_timings.c
index aab57b17d6..1fb0c4eb00 100644
--- a/commands/of_display_timings.c
+++ b/commands/of_display_timings.c
@@ -67,29 +67,11 @@ static int do_of_display_timings(int argc, char *argv[])
 
 	/* Check if external dtb given */
 	if (dtbfile) {
-		void *fdt;
-		size_t size;
-
-		fdt = read_file(dtbfile, &size);
-		if (!fdt) {
-			pr_err("unable to read %s: %s\n", dtbfile,
-				strerror(errno));
-			return -errno;
-		}
-
-		if (file_detect_type(fdt, size) != filetype_oftree) {
-			pr_err("%s is not a oftree file.\n", dtbfile);
-			free(fdt);
-			return -EINVAL;
-		}
-
-		root = of_unflatten_dtb(fdt, size);
-
-		free(fdt);
-
-		if (IS_ERR(root))
+		root = of_read_file(dtbfile);
+		if (IS_ERR(root)) {
+			printf("Cannot open %s: %pe\n", dtbfile, root);
 			return PTR_ERR(root);
-
+		}
 	} else {
 		root = of_get_root_node();
 	}
diff --git a/commands/of_dump.c b/commands/of_dump.c
index c2ca8485cd..86755ff1e4 100644
--- a/commands/of_dump.c
+++ b/commands/of_dump.c
@@ -37,7 +37,6 @@ static int do_of_dump(int argc, char *argv[])
 	int fix = 0;
 	struct device_node *root = NULL, *node, *of_free = NULL;
 	char *dtbfile = NULL;
-	size_t size;
 	const char *nodename;
 	unsigned maxpropsize = ~0;
 	int names_only = 0, properties_only = 0;
@@ -72,19 +71,9 @@ static int do_of_dump(int argc, char *argv[])
 		nodename = argv[optind];
 
 	if (dtbfile) {
-		void *fdt;
-
-		fdt = read_file(dtbfile, &size);
-		if (!fdt) {
-			printf("unable to read %s: %s\n", dtbfile, strerror(errno));
-			return -errno;
-		}
-
-		root = of_unflatten_dtb(fdt, size);
-
-		free(fdt);
-
+		root = of_read_file(dtbfile);
 		if (IS_ERR(root)) {
+			printf("Cannot open %s: %pe\n", dtbfile, root);
 			ret = PTR_ERR(root);
 			goto out;
 		}
diff --git a/commands/of_overlay.c b/commands/of_overlay.c
index b0ca57749b..fda9115a82 100644
--- a/commands/of_overlay.c
+++ b/commands/of_overlay.c
@@ -15,9 +15,7 @@
 static int do_of_overlay(int argc, char *argv[])
 {
 	int ret;
-	struct fdt_header *fdt;
 	struct device_node *overlay;
-	size_t size;
 	bool live_tree = false;
 	int opt;
 
@@ -37,16 +35,11 @@ static int do_of_overlay(int argc, char *argv[])
 		return 1;
 	}
 
-	fdt = read_file(argv[optind], &size);
-	if (!fdt) {
-		printf("cannot read %s\n", argv[optind]);
-		return 1;
-	}
-
-	overlay = of_unflatten_dtb(fdt, size);
-	free(fdt);
-	if (IS_ERR(overlay))
+	overlay = of_read_file(argv[optind]);
+	if (IS_ERR(overlay)) {
+		printf("Cannot open %s: %pe\n", argv[optind], overlay);
 		return PTR_ERR(overlay);
+	}
 
 	if (live_tree) {
 		ret = of_overlay_apply_tree(of_get_root_node(), overlay);
diff --git a/commands/oftree.c b/commands/oftree.c
index 7d4b08c9d3..7b12c86e1d 100644
--- a/commands/oftree.c
+++ b/commands/oftree.c
@@ -31,7 +31,6 @@
 static int do_oftree(int argc, char *argv[])
 {
 	struct fdt_header *fdt = NULL;
-	size_t size;
 	int opt;
 	int probe = 0;
 	char *load = NULL;
@@ -76,18 +75,11 @@ static int do_oftree(int argc, char *argv[])
 	}
 
 	if (load) {
-		fdt = read_file(load, &size);
-		if (!fdt) {
-			printf("unable to read %s\n", load);
-			return 1;
-		}
-
-		root = of_unflatten_dtb(fdt, size);
-
-		free(fdt);
-
-		if (IS_ERR(root))
+		root = of_read_file(load);
+		if (IS_ERR(root)) {
+			printf("Cannot open %s: %pe\n", load, root);
 			return PTR_ERR(root);
+		}
 
 		ret = of_set_root_node(root);
 		if (ret) {