diff --git a/qdf/inc/qdf_hang_event_notifier.h b/qdf/inc/qdf_hang_event_notifier.h
index f13787393948..b5742bd0e1e8 100644
--- a/qdf/inc/qdf_hang_event_notifier.h
+++ b/qdf/inc/qdf_hang_event_notifier.h
@@ -25,7 +25,44 @@
 #include <qdf_notifier.h>
 
 #define QDF_HANG_EVENT_VERSION "1.0"
+/* Max hang event buffer size */
 #define QDF_HANG_EVENT_DATA_SIZE 784
+/* Max offset which host can write */
+#define QDF_WLAN_MAX_HOST_OFFSET 390
+/* Start of the Firmware Data offset */
+#define QDF_WLAN_HANG_FW_OFFSET 392
+
+/**
+ * hang_event_tag: Hang event tag for various modules
+ * @HANG_EVT_TAG_CDS: CDS module hang event tag
+ * @HANG_EVT_TAG_OS_IF: OS interface module hang event tag
+ * @HANG_EVT_TAG_OS_IF_SCAN: scan module hang event tag
+ * @HANG_EVT_TAG_LEGACY_MAC: Legacy mac module hang event tag
+ * @HANG_EVT_TAG_WMI_EVT_HIST: WMI event history hang event tag
+ * @HANG_EVT_TAG_WMI_CMD_HIST: WMI command history hang event tag
+ * @HANG_EVT_TAG_WMI_CMD_HIST: HTC event tag wmi command history hang event tag
+ * @HANG_EVT_TAG_DP_PEER_INFO: DP peer info hang event tag
+ * @HANG_EVT_TAG_CE_INFO: Copy Engine hang event tag
+ */
+enum hang_event_tag {
+	HANG_EVT_TAG_CDS,
+	HANG_EVT_TAG_OS_IF,
+	HANG_EVT_TAG_OS_IF_SCAN,
+	HANG_EVT_TAG_LEGACY_MAC,
+	HANG_EVT_TAG_WMI_EVT_HIST,
+	HANG_EVT_TAG_WMI_CMD_HIST,
+	HANG_EVT_TAG_HTC_CREDIT_HIST,
+	HANG_EVT_TAG_DP_PEER_INFO,
+	HANG_EVT_TAG_CE_INFO
+};
+
+#define QDF_HANG_EVENT_TLV_HDR_SIZE   (sizeof(uint32_t))
+
+#define QDF_HANG_EVT_SET_HDR(tlv_buf, tag, len) \
+	(((uint32_t *)(tlv_buf))[0]) = (((tag) << 16) | ((len) & 0x0000FFFF))
+
+#define QDF_HANG_GET_STRUCT_TLVLEN(tlv_struct) \
+	((uint32_t)(sizeof(tlv_struct) - QDF_HANG_EVENT_TLV_HDR_SIZE))
 
 /**
  * qdf_notifier_data - Private data for notifier data