[RFC PATCH v2 net-next 01/15] net: dsa: tag_8021q: add helpers to deduce whether a VLAN ID is RX or TX VLAN

[Vladimir Oltean]

The sja1105 implementation can be blind about this, but the felix driver
doesn't do exactly what it's being told, so it needs to know whether it
is a TX or an RX VLAN, so it can install the appropriate type of TCAM
rule.

Signed-off-by: Vladimir Oltean <vladimir.olt...@nxp.com>
---
Changes in v2:
None.

 include/linux/dsa/8021q.h | 14 ++++++++++++++
 net/dsa/tag_8021q.c       | 15 +++++++++++++--
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/include/linux/dsa/8021q.h b/include/linux/dsa/8021q.h
index 88cd72dfa4e0..b12b05f1c8b4 100644
--- a/include/linux/dsa/8021q.h
+++ b/include/linux/dsa/8021q.h
@@ -64,6 +64,10 @@ int dsa_8021q_rx_source_port(u16 vid);
 
 u16 dsa_8021q_rx_subvlan(u16 vid);
 
+bool vid_is_dsa_8021q_rxvlan(u16 vid);
+
+bool vid_is_dsa_8021q_txvlan(u16 vid);
+
 bool vid_is_dsa_8021q(u16 vid);
 
 #else
@@ -123,6 +127,16 @@ u16 dsa_8021q_rx_subvlan(u16 vid)
        return 0;
 }
 
+bool vid_is_dsa_8021q_rxvlan(u16 vid)
+{
+       return false;
+}
+
+bool vid_is_dsa_8021q_txvlan(u16 vid)
+{
+       return false;
+}
+
 bool vid_is_dsa_8021q(u16 vid)
 {
        return false;
diff --git a/net/dsa/tag_8021q.c b/net/dsa/tag_8021q.c
index 8e3e8a5b8559..008c1ec6e20c 100644
--- a/net/dsa/tag_8021q.c
+++ b/net/dsa/tag_8021q.c
@@ -133,10 +133,21 @@ u16 dsa_8021q_rx_subvlan(u16 vid)
 }
 EXPORT_SYMBOL_GPL(dsa_8021q_rx_subvlan);
 
+bool vid_is_dsa_8021q_rxvlan(u16 vid)
+{
+       return (vid & DSA_8021Q_DIR_MASK) == DSA_8021Q_DIR_RX;
+}
+EXPORT_SYMBOL_GPL(vid_is_dsa_8021q_rxvlan);
+
+bool vid_is_dsa_8021q_txvlan(u16 vid)
+{
+       return (vid & DSA_8021Q_DIR_MASK) == DSA_8021Q_DIR_TX;
+}
+EXPORT_SYMBOL_GPL(vid_is_dsa_8021q_txvlan);
+
 bool vid_is_dsa_8021q(u16 vid)
 {
-       return ((vid & DSA_8021Q_DIR_MASK) == DSA_8021Q_DIR_RX ||
-               (vid & DSA_8021Q_DIR_MASK) == DSA_8021Q_DIR_TX);
+       return vid_is_dsa_8021q_rxvlan(vid) || vid_is_dsa_8021q_txvlan(vid);
 }
 EXPORT_SYMBOL_GPL(vid_is_dsa_8021q);
 
-- 
2.25.1