void of_alias_scan()

in base.c [2016:2075]

• 45 lines of code
• 16 McCabe index (conditional complexity)

void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
{
	struct property *pp;

	of_aliases = of_find_node_by_path("/aliases");
	of_chosen = of_find_node_by_path("/chosen");
	if (of_chosen == NULL)
		of_chosen = of_find_node_by_path("/chosen@0");

	if (of_chosen) {
		/* linux,stdout-path and /aliases/stdout are for legacy compatibility */
		const char *name = NULL;

		if (of_property_read_string(of_chosen, "stdout-path", &name))
			of_property_read_string(of_chosen, "linux,stdout-path",
						&name);
		if (IS_ENABLED(CONFIG_PPC) && !name)
			of_property_read_string(of_aliases, "stdout", &name);
		if (name)
			of_stdout = of_find_node_opts_by_path(name, &of_stdout_options);
	}

	if (!of_aliases)
		return;

	for_each_property_of_node(of_aliases, pp) {
		const char *start = pp->name;
		const char *end = start + strlen(start);
		struct device_node *np;
		struct alias_prop *ap;
		int id, len;

		/* Skip those we do not want to proceed */
		if (!strcmp(pp->name, "name") ||
		    !strcmp(pp->name, "phandle") ||
		    !strcmp(pp->name, "linux,phandle"))
			continue;

		np = of_find_node_by_path(pp->value);
		if (!np)
			continue;

		/* walk the alias backwards to extract the id and work out
		 * the 'stem' string */
		while (isdigit(*(end-1)) && end > start)
			end--;
		len = end - start;

		if (kstrtoint(end, 10, &id) < 0)
			continue;

		/* Allocate an alias_prop with enough space for the stem */
		ap = dt_alloc(sizeof(*ap) + len + 1, __alignof__(*ap));
		if (!ap)
			continue;
		memset(ap, 0, sizeof(*ap) + len + 1);
		ap->alias = start;
		of_alias_add(ap, np, id, start, len);
	}
}