tbf.h: Improve documentation on several flags
Change-Id: Ice2c164ced039fb4ab621d8f7c2fb85f8348788a
diff --git a/src/tbf.h b/src/tbf.h
index 84c3d39..358a7ad 100644
--- a/src/tbf.h
+++ b/src/tbf.h
@@ -124,9 +124,9 @@
#define GPRS_RLCMAC_FLAG_CCCH 0 /* assignment on CCCH */
#define GPRS_RLCMAC_FLAG_PACCH 1 /* assignment on PACCH */
-#define GPRS_RLCMAC_FLAG_DL_ACK 2 /* downlink acknowledge received */
-#define GPRS_RLCMAC_FLAG_TO_UL_ACK 3
-#define GPRS_RLCMAC_FLAG_TO_DL_ACK 4
+#define GPRS_RLCMAC_FLAG_DL_ACK 2 /* DL TBF: At least one DL ACK/NACK was recieved since it was assigned */
+#define GPRS_RLCMAC_FLAG_TO_UL_ACK 3 /* UL TBF: Failed to receive last polled CTRL ACK confirming our UL ACK/NACK */
+#define GPRS_RLCMAC_FLAG_TO_DL_ACK 4 /* DL TBF: Failed to receive last polled DL ACK/NACK */
#define GPRS_RLCMAC_FLAG_TO_MASK 0xf0 /* timeout bits */
#define T_START(tbf, t, T, r, f) tbf->t_start(t, T, r, f, __FILE__, __LINE__)