diff --git a/share/man/man4/uslcom.4 b/share/man/man4/uslcom.4
index 29e301068ae8..6465054f1208 100644
--- a/share/man/man4/uslcom.4
+++ b/share/man/man4/uslcom.4
@@ -16,7 +16,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd April 26, 2017
+.Dd December 9, 2019
 .Dt USLCOM 4
 .Os
 .Sh NAME
@@ -43,6 +43,11 @@ The
 .Nm
 driver supports Silicon Laboratories CP2101/CP2102/CP2103/CP2104/CP2105
 based USB serial adapters.
+.Pp
+The datasheets for the CP2101/CP2102/CP2103 list the maximum
+supported baud rate as 921,600.
+Empirical testing has shown that the rates 1,228,800 and 1,843,200 also work,
+at least on some hardware, so the driver allows setting those rates.
 .Sh HARDWARE
 The following devices should work with the
 .Nm
diff --git a/sys/dev/usb/serial/uslcom.c b/sys/dev/usb/serial/uslcom.c
index d832da09c5a0..242fc5cbb3f6 100644
--- a/sys/dev/usb/serial/uslcom.c
+++ b/sys/dev/usb/serial/uslcom.c
@@ -624,7 +624,11 @@ uslcom_pre_param(struct ucom_softc *ucom, struct termios *t)
 	case USLCOM_PARTNUM_CP2102:
 	case USLCOM_PARTNUM_CP2103:
 	default:
-		maxspeed = 921600;
+		/*
+		 * Datasheet for cp2102 says 921600 max.  Testing shows that
+		 * 1228800 and 1843200 work fine.
+		 */
+		maxspeed = 1843200;
 		break;
 	}
 	if (t->c_ospeed <= 0 || t->c_ospeed > maxspeed)