Merge branches 'topic/hwspinlock' and 'topic/nolock' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap into regmap-const

drivers/base/regmap/internal.h

@@ -77,6 +77,7 @@ struct regmap {
 	int async_ret;
 
 #ifdef CONFIG_DEBUG_FS
+	bool debugfs_disable;
 	struct dentry *debugfs;
 	const char *debugfs_name;
 
@@ -215,10 +216,17 @@ struct regmap_field {
 extern void regmap_debugfs_initcall(void);
 extern void regmap_debugfs_init(struct regmap *map, const char *name);
 extern void regmap_debugfs_exit(struct regmap *map);
+
+static inline void regmap_debugfs_disable(struct regmap *map)
+{
+	map->debugfs_disable = true;
+}
+
 #else
 static inline void regmap_debugfs_initcall(void) { }
 static inline void regmap_debugfs_init(struct regmap *map, const char *name) { }
 static inline void regmap_debugfs_exit(struct regmap *map) { }
+static inline void regmap_debugfs_disable(struct regmap *map) { }
 #endif
 
 /* regcache core declarations */

drivers/base/regmap/regmap-debugfs.c

@@ -529,6 +529,9 @@ void regmap_debugfs_init(struct regmap *map, const char *name)
 	struct regmap_range_node *range_node;
 	const char *devname = "dummy";
 
+	if (map->debugfs_disable)
+		return;
+
 	/* If we don't have the debugfs root yet, postpone init */
 	if (!regmap_debugfs_root) {
 		struct regmap_debugfs_node *node;

drivers/base/regmap/regmap.c

@@ -457,6 +457,11 @@ static void regmap_unlock_hwlock_irqrestore(void *__map)
 	hwspin_unlock_irqrestore(map->hwlock, &map->spinlock_flags);
 }
 
+static void regmap_lock_unlock_none(void *__map)
+{
+
+}
+
 static void regmap_lock_mutex(void *__map)
 {
 	struct regmap *map = __map;
@@ -667,7 +672,10 @@ struct regmap *__regmap_init(struct device *dev,
 		goto err;
 	}
 
-	if (config->lock && config->unlock) {
+	if (config->disable_locking) {
+		map->lock = map->unlock = regmap_lock_unlock_none;
+		regmap_debugfs_disable(map);
+	} else if (config->lock && config->unlock) {
 		map->lock = config->lock;
 		map->unlock = config->unlock;
 		map->lock_arg = config->lock_arg;

include/linux/regmap.h

@@ -264,6 +264,9 @@ typedef void (*regmap_unlock)(void *);
  *                field is NULL but precious_table (see below) is not, the
  *                check is performed on such table (a register is precious if
  *                it belongs to one of the ranges specified by precious_table).
+ * @disable_locking: This regmap is either protected by external means or
+ *                   is guaranteed not be be accessed from multiple threads.
+ *                   Don't use any locking mechanisms.
  * @lock:	  Optional lock callback (overrides regmap's default lock
  *		  function, based on spinlock or mutex).
  * @unlock:	  As above for unlocking.
@@ -333,6 +336,8 @@ struct regmap_config {
 	bool (*readable_reg)(struct device *dev, unsigned int reg);
 	bool (*volatile_reg)(struct device *dev, unsigned int reg);
 	bool (*precious_reg)(struct device *dev, unsigned int reg);
+
+	bool disable_locking;
 	regmap_lock lock;
 	regmap_unlock unlock;
 	void *lock_arg;