[PATCH] fdtdec: use full path in fdtdec_get_alias_seq comparison

[Vladimir Oltean]

From: Vladimir Oltean <vladimir.oltean at nxp.com>

Currently fdtdec_get_alias_seq() calls fdt_get_name() which returns only
the name of the leaf node. So it needs to also trim the path of the
alias to the leaf name only, leading to imperfect matches.

This means that the following aliases:

    /aliases {
        eth0 = "/dspi at 2120000/ethernet-switch at 0/ports/port at 0";
        eth1 = "/pcie at 1f0000000/pci at 0,5/ports/port at 0";
    };

will make fdtdec_get_alias_seq to return a seq of zero for both aliases,
as the match will only take place on the "port at 0" portion.

Fix this by calling fdt_get_path and comparing the full path of the
alias.

Fixes: 5c33c9fdbb3f ("fdt: Add a function to get the alias sequence of a node")
Signed-off-by: Vladimir Oltean <vladimir.oltean at nxp.com>
---
 lib/fdtdec.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index eb11fc898e30..55c1b36e823b 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -455,13 +455,14 @@ int fdtdec_get_alias_seq(const void *blob, const char *base, int offset,
 			 int *seqp)
 {
 	int base_len = strlen(base);
-	const char *find_name;
-	int find_namelen;
 	int prop_offset;
+	char path[64];
+	int path_len;
 	int aliases;
 
-	find_name = fdt_get_name(blob, offset, &find_namelen);
-	debug("Looking for '%s' at %d, name %s\n", base, offset, find_name);
+	fdt_get_path(blob, offset, path, sizeof(path));
+	path_len = strlen(path);
+	debug("Looking for '%s' at %d, path %s\n", base, offset, path);
 
 	aliases = fdt_path_offset(blob, "/aliases");
 	for (prop_offset = fdt_first_property_offset(blob, aliases);
@@ -469,17 +470,15 @@ int fdtdec_get_alias_seq(const void *blob, const char *base, int offset,
 	     prop_offset = fdt_next_property_offset(blob, prop_offset)) {
 		const char *prop;
 		const char *name;
-		const char *slash;
 		int len, val;
 
 		prop = fdt_getprop_by_offset(blob, prop_offset, &name, &len);
 		debug("   - %s, %s\n", name, prop);
-		if (len < find_namelen || *prop != '/' || prop[len - 1] ||
+		if (len < path_len || *prop != '/' || prop[len - 1] ||
 		    strncmp(name, base, base_len))
 			continue;
 
-		slash = strrchr(prop, '/');
-		if (strcmp(slash + 1, find_name))
+		if (strcmp(prop, path))
 			continue;
 		val = trailing_strtol(name);
 		if (val != -1) {
-- 
2.17.1