From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sascha Hauer Subject: [PATCH 1/2] of: Add helper for getting the maximum alias index for a stem Date: Thu, 22 May 2014 17:30:22 +0200 Message-ID: <1400772623-8390-2-git-send-email-s.hauer@pengutronix.de> References: <1400772623-8390-1-git-send-email-s.hauer@pengutronix.de> Return-path: Received: from metis.ext.pengutronix.de ([92.198.50.35]:60861 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751422AbaEVPan (ORCPT ); Thu, 22 May 2014 11:30:43 -0400 In-Reply-To: <1400772623-8390-1-git-send-email-s.hauer@pengutronix.de> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: linux-mmc@vger.kernel.org Cc: Dirk Behme , Fabio Estevam , ptx@pengutronix.de, Stephen Warren , Sascha Hauer 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 --- drivers/of/base.c | 29 +++++++++++++++++++++++++++++ include/linux/of.h | 6 ++++++ 2 files changed, 35 insertions(+) diff --git a/drivers/of/base.c b/drivers/of/base.c index f807d0e..f953b9d 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -1758,6 +1758,35 @@ 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_aliases_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_aliases_mutex); + + return max; +} + /** * of_alias_scan - Scan all properties of 'aliases' node * diff --git a/include/linux/of.h b/include/linux/of.h index 276c546..963e295 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -305,6 +305,7 @@ extern int of_count_phandle_with_args(const struct device_node *np, extern void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align)); extern int of_alias_get_id(struct device_node *np, const char *stem); +extern int of_alias_max_index(const char *stem); extern int of_machine_is_compatible(const char *compat); @@ -532,6 +533,11 @@ static inline int of_alias_get_id(struct device_node *np, const char *stem) return -ENOSYS; } +static inline int of_alias_max_index(const char *stem) +{ + return -ENODEV; +} + static inline int of_machine_is_compatible(const char *compat) { return 0; -- 2.0.0.rc0