diff --git a/include/uapi/linux/can/error.h b/include/uapi/linux/can/error.h
index bfc4b5d22a5e601107b887c0913d89d94a7ee664..383f3d508a53d16a8976f86563a842bd5e4d5b54 100644
--- a/include/uapi/linux/can/error.h
+++ b/include/uapi/linux/can/error.h
@@ -120,6 +120,9 @@
 #define CAN_ERR_TRX_CANL_SHORT_TO_GND  0x70 /* 0111 0000 */
 #define CAN_ERR_TRX_CANL_SHORT_TO_CANH 0x80 /* 1000 0000 */
 
-/* controller specific additional information / data[5..7] */
+/* data[5] is reserved (do not use) */
+
+/* TX error counter / data[6] */
+/* RX error counter / data[7] */
 
 #endif /* _UAPI_CAN_ERROR_H */