regmap: Reject fast_io regmap configurations with RBTREE and MAPLE ca…

…ches REGCACHE_RBTREE and REGCACHE_MAPLE dynamically allocate memory for regmap operations. This is incompatible with spinlock based locking which is used for fast_io operations. Reject affected configurations. Signed-off-by: Guenter Roeck <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Mark Brown <[email protected]>
niw · Jul 20, 2023 · ee43f5b · ee43f5b
1 parent 99aae70
commit ee43f5b
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
@@ -723,6 +723,15 @@ struct regmap *__regmap_init(struct device *dev,
 	} else {
 		if ((bus && bus->fast_io) ||
 		    config->fast_io) {
+			/*
+			 * fast_io is incompatible with REGCACHE_RBTREE and REGCACHE_MAPLE
+			 * since both need to dynamically allocate memory.
+			 */
+			if (config->cache_type == REGCACHE_RBTREE ||
+			    config->cache_type == REGCACHE_MAPLE) {
+				ret = -EINVAL;
+				goto err_name;
+			}
 			if (config->use_raw_spinlock) {
 				raw_spin_lock_init(&map->raw_spinlock);
 				map->lock = regmap_lock_raw_spinlock;