diff --git a/camlibs/ptp/ptp.h b/camlibs/ptp/ptp.h
index bde2b9760..f76eb5ffe 100644
--- a/camlibs/ptp/ptp.h
+++ b/camlibs/ptp/ptp.h
@@ -51,7 +51,7 @@ typedef struct _PTPReq PTPReq;
 #define PTP_TYPE_REQ                    0x0001
 #define PTP_TYPE_DATA                   0x0002
 #define PTP_TYPE_RESP                   0x0003
-#define PTP_REQ_DATALEN                 16384
+#define PTP_TYPE_EVENT			0x0004
 
 // Operation Codes