diff --git a/include/osmocom/core/logging.h b/include/osmocom/core/logging.h
index 0078425..f1304f5 100644
--- a/include/osmocom/core/logging.h
+++ b/include/osmocom/core/logging.h
@@ -151,7 +151,8 @@
 #define DLNSSIGNAL	-23	/*!< Osmocom NS layer signal pdus */
 #define DLIUUP		-24	/*!< Osmocom IuUP layer */
 #define DLPFCP		-25	/*!< Osmocom Packet Forwarding Control Protocol */
-#define OSMO_NUM_DLIB	25	/*!< Number of logging sub-systems in libraries */
+#define DLCSN1		-26	/*!< CSN.1 (Concrete Syntax Notation 1) codec */
+#define OSMO_NUM_DLIB	26	/*!< Number of logging sub-systems in libraries */
 
 /* Colors that can be used in log_info_cat.color */
 #define OSMO_LOGCOLOR_NORMAL NULL
diff --git a/src/logging.c b/src/logging.c
index 1a0abc2..ce42e4c 100644
--- a/src/logging.c
+++ b/src/logging.c
@@ -307,6 +307,12 @@
 		.enabled = 1, .loglevel = LOGL_NOTICE,
 		.color = "\033[38;5;51m",
 	},
+	[INT2IDX(DLCSN1)] = {
+		.name = "DLCSN1",
+		.description = "libosmo-csn1 Concrete Syntax Notation 1 codec",
+		.enabled = 1, .loglevel = LOGL_NOTICE,
+		.color = "\033[38;5;11m",
+	},
 };
 
 void assert_loginfo(const char *src)
diff --git a/tests/logging/logging_vty_test.vty b/tests/logging/logging_vty_test.vty
index 860f5c5..2cff62c 100644
--- a/tests/logging/logging_vty_test.vty
+++ b/tests/logging/logging_vty_test.vty
@@ -54,7 +54,7 @@
   logging print level (0|1)
   logging print file (0|1|basename) [last]
   logging set-log-mask MASK
-  logging level (aa|bb|ccc|dddd|eee|lglobal|llapd|linp|lmux|lmi|lmib|lsms|lctrl|lgtp|lstats|lgsup|loap|lss7|lsccp|lsua|lm3ua|lmgcp|ljibuf|lrspro|lns|lbssgp|lnsdata|lnssignal|liuup|lpfcp) (debug|info|notice|error|fatal)
+  logging level (aa|bb|ccc|dddd|eee|lglobal|llapd|linp|lmux|lmi|lmib|lsms|lctrl|lgtp|lstats|lgsup|loap|lss7|lsccp|lsua|lm3ua|lmgcp|ljibuf|lrspro|lns|lbssgp|lnsdata|lnssignal|liuup|lpfcp|lcsn1) (debug|info|notice|error|fatal)
   logging level set-all (debug|info|notice|error|fatal)
   logging level force-all (debug|info|notice|error|fatal)
   no logging level force-all
@@ -472,7 +472,7 @@
 
 logging_vty_test# list
 ...
-  logp (aa|bb|ccc|dddd|eee|lglobal|llapd|linp|lmux|lmi|lmib|lsms|lctrl|lgtp|lstats|lgsup|loap|lss7|lsccp|lsua|lm3ua|lmgcp|ljibuf|lrspro|lns|lbssgp|lnsdata|lnssignal|liuup|lpfcp) (debug|info|notice|error|fatal) .LOGMESSAGE
+  logp (aa|bb|ccc|dddd|eee|lglobal|llapd|linp|lmux|lmi|lmib|lsms|lctrl|lgtp|lstats|lgsup|loap|lss7|lsccp|lsua|lm3ua|lmgcp|ljibuf|lrspro|lns|lbssgp|lnsdata|lnssignal|liuup|lpfcp|lcsn1) (debug|info|notice|error|fatal) .LOGMESSAGE
 ...
 
 logging_vty_test# logp?
@@ -509,6 +509,7 @@
   lnssignal  GPRS NS layer signal PDU
   liuup      Iu UP layer
   lpfcp      libosmo-pfcp Packet Forwarding Control Protocol
+  lcsn1      libosmo-csn1 Concrete Syntax Notation 1 codec
 
 logging_vty_test# logp lglobal ?
   debug   Log debug messages and higher levels