+/* Message logging helpers with subsystem-specific prefix string. */
+#define LOG_PREFIX "hantek-dso: "
+#define sr_log(l, s, args...) sr_log(l, LOG_PREFIX s, ## args)
+#define sr_spew(s, args...) sr_spew(LOG_PREFIX s, ## args)
+#define sr_dbg(s, args...) sr_dbg(LOG_PREFIX s, ## args)
+#define sr_info(s, args...) sr_info(LOG_PREFIX s, ## args)
+#define sr_warn(s, args...) sr_warn(LOG_PREFIX s, ## args)
+#define sr_err(s, args...) sr_err(LOG_PREFIX s, ## args)
+
+#define USB_INTERFACE 0
+#define USB_CONFIGURATION 1
+#define DSO_EP_IN 0x86
+#define DSO_EP_OUT 0x02