[src/trunk]: src/sys/dev/usb add comments to show the RX filter intent

[nisimura <nisimura%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/b5ab397ef134
branches:  trunk
changeset: 969720:b5ab397ef134
user:      nisimura <nisimura%NetBSD.org@localhost>
date:      Sat Feb 29 04:27:53 2020 +0000

description:
add comments to show the RX filter intent

diffstat:

 sys/dev/usb/if_axe.c |  10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)

diffs (37 lines):

diff -r 6f84f1a1fa6d -r b5ab397ef134 sys/dev/usb/if_axe.c
--- a/sys/dev/usb/if_axe.c      Sat Feb 29 04:27:01 2020 +0000
+++ b/sys/dev/usb/if_axe.c      Sat Feb 29 04:27:53 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_axe.c,v 1.125 2020/02/29 04:02:06 nisimura Exp $    */
+/*     $NetBSD: if_axe.c,v 1.126 2020/02/29 04:27:53 nisimura Exp $    */
 /*     $OpenBSD: if_axe.c,v 1.137 2016/04/13 11:03:37 mpi Exp $ */
 
 /*
@@ -87,7 +87,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_axe.c,v 1.125 2020/02/29 04:02:06 nisimura Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_axe.c,v 1.126 2020/02/29 04:27:53 nisimura Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_usb.h"
@@ -475,15 +475,15 @@
        }
        ETHER_UNLOCK(ec);
 
-       rxmode |= AXE_RXCMD_MULTICAST;
+       rxmode |= AXE_RXCMD_MULTICAST;  /* activate mcast hash filter */
        axe_cmd(sc, AXE_CMD_WRITE_MCAST, 0, 0, hashtbl);
        axe_cmd(sc, AXE_CMD_RXCTL_WRITE, 0, rxmode, NULL);
        return;
 
  allmulti:
        if (ifp->if_flags & IFF_PROMISC)
-               rxmode |= AXE_RXCMD_PROMISC;
-       rxmode |= AXE_RXCMD_ALLMULTI;
+               rxmode |= AXE_RXCMD_PROMISC; /* run promisc. mode */
+       rxmode |= AXE_RXCMD_ALLMULTI;   /* accept all mcast frames */
        axe_cmd(sc, AXE_CMD_RXCTL_WRITE, 0, rxmode, NULL);
 }