From 5ebc7c7e27780ce9a16289eeb87290eebd248ea9 Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Thu, 31 Jan 2019 16:30:57 +0100 Subject: [PATCH] dm: core: Add of_alias_get_highest_id() The same functionality was added to Linux for i2c bus registration with this commit message: " of: base: add function to get highest id of an alias stem I2C supports adding adapters using either a dynamic or fixed id. The latter is provided by aliases in the DT case. To prevent id collisions of those two types, install this function which gives us the highest fixed id, so we can then let the dynamically created ones come after this highest number. Signed-off-by: Wolfram Sang Acked-by: Rob Herring Signed-off-by: Wolfram Sang " Add it also to U-Boot for DM I2C support. Signed-off-by: Michal Simek Reviewed-by: Heiko Schocher Reviewed-by: Simon Glass --- drivers/core/of_access.c | 18 ++++++++++++++++++ include/dm/of_access.h | 10 ++++++++++ 2 files changed, 28 insertions(+) diff --git a/drivers/core/of_access.c b/drivers/core/of_access.c index 14c020a..945b814 100644 --- a/drivers/core/of_access.c +++ b/drivers/core/of_access.c @@ -812,6 +812,24 @@ int of_alias_get_id(const struct device_node *np, const char *stem) return id; } +int of_alias_get_highest_id(const char *stem) +{ + struct alias_prop *app; + int id = -1; + + mutex_lock(&of_mutex); + list_for_each_entry(app, &aliases_lookup, link) { + if (strcmp(app->stem, stem) != 0) + continue; + + if (app->id > id) + id = app->id; + } + mutex_unlock(&of_mutex); + + return id; +} + struct device_node *of_get_stdout(void) { return of_stdout; diff --git a/include/dm/of_access.h b/include/dm/of_access.h index 5ed1a0c..13fedb7 100644 --- a/include/dm/of_access.h +++ b/include/dm/of_access.h @@ -425,6 +425,16 @@ int of_alias_scan(void); int of_alias_get_id(const struct device_node *np, const char *stem); /** + * of_alias_get_highest_id - Get highest alias id for the given stem + * @stem: Alias stem to be examined + * + * The function travels the lookup table to get the highest alias id for the + * given alias stem. + * @return alias ID, if found, else -1 + */ +int of_alias_get_highest_id(const char *stem); + +/** * of_get_stdout() - Get node to use for stdout * * @return node referred to by stdout-path alias, or NULL if none -- 2.7.4