[PATCH net 3/3] Documentation: networking: dsa: Describe port_vlan_filtering

[Florian Fainelli <f.fainelli@gmail.com>]

Described what the port_vlan_filtering function is supposed to
accomplish.

Fixes: fb2dabad69f0 ("net: dsa: support VLAN filtering switchdev attr")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 Documentation/networking/dsa/dsa.txt | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/networking/dsa/dsa.txt b/Documentation/networking/dsa/dsa.txt
index 411b57fd73aa..a42fd2ec32a5 100644
--- a/Documentation/networking/dsa/dsa.txt
+++ b/Documentation/networking/dsa/dsa.txt
@@ -535,6 +535,12 @@ Bridge layer
 Bridge VLAN filtering
 ---------------------
 
+- port_vlan_filtering: bridge layer function invoked when the bridge gets
+  configured for turning on or off VLAN filtering. If nothing specific needs to
+  be done at the hardware level, 0 must be returned. When VLAN filtering is
+  turned on, the hardware must be programmed with rejecting non-802.1Q frames,
+  when turned off the switch must accept any 802.1Q frames.
+
 - port_vlan_prepare: bridge layer function invoked when the bridge prepares the
   configuration of a VLAN on the given port. If the operation is not supported
   by the hardware, this function should return -EOPNOTSUPP to inform the bridge
-- 
2.7.4