Subject: [PATCH AUTOSEL 5.13 159/189] net: dsa: b53: Create default VLAN entry explicitly

From: Sasha Levin <[email-masked]>
Date: Tue, 6 Jul 2021 07:13:39 -0400

From: Florian Fainelli <[email-masked]>

[ Upstream commit 64a81b24487f0d2fba0f033029eec2abc7d82cee ]

In case CONFIG_VLAN_8021Q is not set, there will be no call down to the
b53 driver to ensure that the default PVID VLAN entry will be configured
with the appropriate untagged attribute towards the CPU port. We were
implicitly relying on dsa_slave_vlan_rx_add_vid() to do that for us,
instead make it explicit.

Reported-by: Vladimir Oltean <[email-masked]>
Signed-off-by: Florian Fainelli <[email-masked]>
Reviewed-by: Vladimir Oltean <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 drivers/net/dsa/b53/b53_common.c | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
index 3ca6b394dd5f..67a7de87c17a 100644
--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c
@@ -728,6 +728,13 @@ static u16 b53_default_pvid(struct b53_device *dev)
 		return 0;
 }
 
+static bool b53_vlan_port_needs_forced_tagged(struct dsa_switch *ds, int port)
+{
+	struct b53_device *dev = ds->priv;
+
+	return dev->tag_protocol == DSA_TAG_PROTO_NONE && dsa_is_cpu_port(ds, port);
+}
+
 int b53_configure_vlan(struct dsa_switch *ds)
 {
 	struct b53_device *dev = ds->priv;
@@ -748,9 +755,20 @@ int b53_configure_vlan(struct dsa_switch *ds)
 
 	b53_enable_vlan(dev, -1, dev->vlan_enabled, ds->vlan_filtering);
 
-	b53_for_each_port(dev, i)
+	/* Create an untagged VLAN entry for the default PVID in case
+	 * CONFIG_VLAN_8021Q is disabled and there are no calls to
+	 * dsa_slave_vlan_rx_add_vid() to create the default VLAN
+	 * entry. Do this only when the tagging protocol is not
+	 * DSA_TAG_PROTO_NONE
+	 */
+	b53_for_each_port(dev, i) {
+		v = &dev->vlans[def_vid];
+		v->members |= BIT(i);
+		if (!b53_vlan_port_needs_forced_tagged(ds, i))
+			v->untag = v->members;
 		b53_write16(dev, B53_VLAN_PAGE,
 			    B53_VLAN_PORT_DEF_TAG(i), def_vid);
+	}
 
 	/* Upon initial call we have not set-up any VLANs, but upon
 	 * system resume, we need to restore all VLAN entries.
-- 
2.30.2