Re: [RFC PATCH 1/9] net: dsa: Add tag handling for Hirschmann Hellcreek switches

The Hirschmann Hellcreek TSN switches have a special tagging protocol for frames
exchanged between the CPU port and the master interface. The format is a one
byte trailer indicating the destination or origin port.

It's quite similar to the Micrel KSZ tagging. That's why the implementation is
based on that code.

Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
---
 include/net/dsa.h       |   2 +
 net/dsa/Kconfig         |   6 +++
 net/dsa/Makefile        |   1 +
 net/dsa/tag_hellcreek.c | 101 ++++++++++++++++++++++++++++++++++++++++
 4 files changed, 110 insertions(+)
 create mode 100644 net/dsa/tag_hellcreek.c

diff --git a/include/net/dsa.h b/include/net/dsa.h
index 50389772c597..2784c4851d92 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h

@@ -44,6 +44,7 @@ struct phylink_link_state;
 #define DSA_TAG_PROTO_KSZ8795_VALUE		14
 #define DSA_TAG_PROTO_OCELOT_VALUE		15
 #define DSA_TAG_PROTO_AR9331_VALUE		16
+#define DSA_TAG_PROTO_HELLCREEK_VALUE		17
 
 enum dsa_tag_protocol {
 	DSA_TAG_PROTO_NONE		= DSA_TAG_PROTO_NONE_VALUE,

@@ -63,6 +64,7 @@ enum dsa_tag_protocol {
 	DSA_TAG_PROTO_KSZ8795		= DSA_TAG_PROTO_KSZ8795_VALUE,
 	DSA_TAG_PROTO_OCELOT		= DSA_TAG_PROTO_OCELOT_VALUE,
 	DSA_TAG_PROTO_AR9331		= DSA_TAG_PROTO_AR9331_VALUE,
+	DSA_TAG_PROTO_HELLCREEK		= DSA_TAG_PROTO_HELLCREEK_VALUE,
 };
 
 struct packet_type;

diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig
index d5bc6ac599ef..edc0c3ab6a4e 100644
--- a/net/dsa/Kconfig
+++ b/net/dsa/Kconfig

@@ -121,4 +121,10 @@ config NET_DSA_TAG_TRAILER
 	  Say Y or M if you want to enable support for tagging frames at
 	  with a trailed. e.g. Marvell 88E6060.
 
+config NET_DSA_TAG_HELLCREEK
+	tristate "Tag driver for Hirschmann Hellcreek TSN switches"
+	help
+	  Say Y or M if you want to enable support for tagging frames
+	  for the Hirschmann Hellcreek TSN switches.
+