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>

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>
Mark Brown
1 parent 50b776fc71
Showing 2 changed files with 35 additions and 0 deletions Side-by-side Diff
drivers/base/regmap/regmap.c
include/linux/regmap.h
@@ -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)
@@ -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);
...	...	@@ -231,6 +231,39 @@
231	231	EXPORT_SYMBOL_GPL(regmap_init);
232	232
233	233	/**
	234	+ * regmap_reinit_cache(): Reinitialise the current register cache
	235	+ *
	236	+ * @map: Register map to operate on.
	237	+ * @config: New configuration. Only the cache data will be used.
	238	+ *
	239	+ * Discard any existing register cache for the map and initialize a
	240	+ * new cache. This can be used to restore the cache to defaults or to
	241	+ * update the cache configuration to reflect runtime discovery of the
	242	+ * hardware.
	243	+ */
	244	+int regmap_reinit_cache(struct regmap map, const struct regmap_config config)
	245	+{
	246	+ int ret;
	247	+
	248	+ mutex_lock(&map->lock);
	249	+
	250	+ regcache_exit(map);
	251	+
	252	+ map->max_register = config->max_register;
	253	+ map->writeable_reg = config->writeable_reg;
	254	+ map->readable_reg = config->readable_reg;
	255	+ map->volatile_reg = config->volatile_reg;
	256	+ map->precious_reg = config->precious_reg;
	257	+ map->cache_type = config->cache_type;
	258	+
	259	+ ret = regcache_init(map, config);
	260	+
	261	+ mutex_unlock(&map->lock);
	262	+
	263	+ return ret;
	264	+}
	265	+
	266	+/**
234	267	* regmap_exit(): Free a previously allocated register map
235	268	*/
236	269	void regmap_exit(struct regmap *map)
...	...	@@ -129,6 +129,8 @@
129	129	const struct regmap_config *config);
130	130
131	131	void regmap_exit(struct regmap *map);
	132	+int regmap_reinit_cache(struct regmap *map,
	133	+ const struct regmap_config *config);
132	134	int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
133	135	int regmap_raw_write(struct regmap *map, unsigned int reg,
134	136	const void *val, size_t val_len);