diff options
| author | Sascha Hauer <s.hauer@pengutronix.de> | 2014-05-22 17:30:22 +0200 |
|---|---|---|
| committer | Leonard Crestez <leonard.crestez@nxp.com> | 2018-08-24 12:20:42 +0300 |
| commit | 9787bebaa8249a62008b71ddb1592254f9593bfc (patch) | |
| tree | 3ab4b079de55e50ae95dc81533f310ea148ff358 /drivers/of | |
| parent | 0b8a6971ced6489ebda85c3b82c621a7c3900cec (diff) | |
of: Add helper for getting the maximum alias index for a stem
of_alias_max_index will return the maximum number for which an
alias of a given stem exists. This is useful for frameworks
whishing to reserve a number of device slots from dynamic
allocation.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
(cherry picked from commit 5ce2ad39b36fd48b9f77249198655da7cbcc7ee5)
Conflicts:
include/linux/of.h
Diffstat (limited to 'drivers/of')
| -rw-r--r-- | drivers/of/base.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c index 466b285cef3e..42073482ab64 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -2049,6 +2049,35 @@ static void of_alias_add(struct alias_prop *ap, struct device_node *np, ap->alias, ap->stem, ap->id, of_node_full_name(np)); } +/* + * of_alias_max_index() - get the maximum index for a given alias stem + * @stem: The alias stem for which the maximum index is searched for + * + * Given an alias stem (the alias without the number) this function + * returns the maximum number for which an alias exists. + * + * Return: The maximum existing alias index or -ENODEV if no alias + * exists for this stem. + */ +int of_alias_max_index(const char *stem) +{ + struct alias_prop *app; + int max = -ENODEV; + + mutex_lock(&of_mutex); + + list_for_each_entry(app, &aliases_lookup, link) { + if (strcmp(app->stem, stem)) + continue; + if (app->id > max) + max = app->id; + } + + mutex_unlock(&of_mutex); + + return max; +} + /** * of_alias_scan - Scan all properties of the 'aliases' node * |