diff --git a/hwdriver.c b/hwdriver.c
index bf473da6..4c2ae142 100644
--- a/hwdriver.c
+++ b/hwdriver.c
@@ -377,7 +377,7 @@ SR_API int sr_config_set(const struct sr_dev_inst *sdi, int key,
  *         but this is not to be flagged as an error by the caller; merely
  *         as an indication that it's not applicable.
  */
-SR_API int sr_config_list(struct sr_dev_driver *driver, int key,
+SR_API int sr_config_list(const struct sr_dev_driver *driver, int key,
 		const void **data, const struct sr_dev_inst *sdi)
 {
 	int ret;
diff --git a/proto.h b/proto.h
index cf99d1bb..c801f6cd 100644
--- a/proto.h
+++ b/proto.h
@@ -72,7 +72,7 @@ SR_API int sr_config_get(const struct sr_dev_driver *driver, int key,
 		const void **data, const struct sr_dev_inst *sdi);
 SR_API int sr_config_set(const struct sr_dev_inst *sdi, int key,
 		const void *value);
-SR_API int sr_config_list(struct sr_dev_driver *driver, int key,
+SR_API int sr_config_list(const struct sr_dev_driver *driver, int key,
 		const void **data, const struct sr_dev_inst *sdi);
 SR_API const struct sr_config_info *sr_config_info_get(int key);
 SR_API const struct sr_config_info *sr_config_info_name_get(const char *optname);