SR_PRIV int lps_read_reply(struct sr_serial_dev_inst *serial, char **buf, int *buflen);
SR_PRIV int lps_send_va(struct sr_serial_dev_inst *serial, const char *fmt, va_list args);
SR_PRIV int lps_cmd_ok(struct sr_serial_dev_inst *serial, const char *fmt, ...);
SR_PRIV int lps_read_reply(struct sr_serial_dev_inst *serial, char **buf, int *buflen);
SR_PRIV int lps_send_va(struct sr_serial_dev_inst *serial, const char *fmt, va_list args);
SR_PRIV int lps_cmd_ok(struct sr_serial_dev_inst *serial, const char *fmt, ...);