regmap: Allow drivers to reinitialise the register cache at runtime
Sometimes the register map information may change in ways that drivers can
discover at runtime. For example, new revisions of a device may add new
registers. Support runtime discovery by drivers by allowing the register
cache to be reinitialised with a new function regmap_reinit_cache() which
discards the existing cache and creates a new one.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 3aca18d..579e85b 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -231,6 +231,39 @@
EXPORT_SYMBOL_GPL(regmap_init);
/**
+ * regmap_reinit_cache(): Reinitialise the current register cache
+ *
+ * @map: Register map to operate on.
+ * @config: New configuration. Only the cache data will be used.
+ *
+ * Discard any existing register cache for the map and initialize a
+ * new cache. This can be used to restore the cache to defaults or to
+ * update the cache configuration to reflect runtime discovery of the
+ * hardware.
+ */
+int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config)
+{
+ int ret;
+
+ mutex_lock(&map->lock);
+
+ regcache_exit(map);
+
+ map->max_register = config->max_register;
+ map->writeable_reg = config->writeable_reg;
+ map->readable_reg = config->readable_reg;
+ map->volatile_reg = config->volatile_reg;
+ map->precious_reg = config->precious_reg;
+ map->cache_type = config->cache_type;
+
+ ret = regcache_init(map, config);
+
+ mutex_unlock(&map->lock);
+
+ return ret;
+}
+
+/**
* regmap_exit(): Free a previously allocated register map
*/
void regmap_exit(struct regmap *map)
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index bebda14..86923a9 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -129,6 +129,8 @@
const struct regmap_config *config);
void regmap_exit(struct regmap *map);
+int regmap_reinit_cache(struct regmap *map,
+ const struct regmap_config *config);
int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
int regmap_raw_write(struct regmap *map, unsigned int reg,
const void *val, size_t val_len);