int pb_protocol_serialise_string(char *pos, const char *str);
char *pb_protocol_deserialise_string(void *ctx,
const struct pb_protocol_message *message);
int pb_protocol_serialise_device(const struct device *dev, char *buf, int buf_len);
int pb_protocol_serialise_string(char *pos, const char *str);
char *pb_protocol_deserialise_string(void *ctx,
const struct pb_protocol_message *message);
int pb_protocol_serialise_device(const struct device *dev, char *buf, int buf_len);