[PATCH net-next v3 5/7] net: dsa: mt7530: improve code path for setting up port 5

From: Arınç ÜNAL via B4 Relay
Date: Mon Jan 22 2024 - 00:38:15 EST


From: Arınç ÜNAL <arinc.unal@xxxxxxxxxx>

There're two code paths for setting up port 5:

mt7530_setup()
-> mt7530_setup_port5()

mt753x_phylink_mac_config()
-> mt753x_mac_config()
-> mt7530_mac_config()
-> mt7530_setup_port5()

Currently mt7530_setup_port5() from mt7530_setup() always runs. If port 5
is used as a CPU, DSA, or user port, mt7530_setup_port5() from
mt753x_phylink_mac_config() won't run. That is because priv->p5_interface
set on mt7530_setup_port5() will match state->interface on
mt753x_phylink_mac_config() which will stop running mt7530_setup_port5()
again.

Therefore, mt7530_setup_port5() will never run from
mt753x_phylink_mac_config().

Address this by not running mt7530_setup_port5() from mt7530_setup() if
port 5 is used as a CPU, DSA, or user port. This driver isn't in the
dsa_switches_apply_workarounds[] array so phylink will always be present.

To keep the cases where port 5 isn't controlled by phylink working as
before, preserve the mt7530_setup_port5() call from mt7530_setup().

Do not set priv->p5_intf_sel to P5_DISABLED. It is already set to that when
"priv" is allocated.

Move setting the interface to a more specific location. It's supposed to be
overwritten if PHY muxing is detected.

Improve the comment which explains the process.

Signed-off-by: Arınç ÜNAL <arinc.unal@xxxxxxxxxx>
Reviewed-by: Vladimir Oltean <olteanv@xxxxxxxxx>
---
drivers/net/dsa/mt7530.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index 93d8498ce274..33c15f10de34 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -2308,16 +2308,15 @@ mt7530_setup(struct dsa_switch *ds)
return ret;

/* Setup port 5 */
- priv->p5_intf_sel = P5_DISABLED;
- interface = PHY_INTERFACE_MODE_NA;
-
if (!dsa_is_unused_port(ds, 5)) {
priv->p5_intf_sel = P5_INTF_SEL_GMAC5;
- ret = of_get_phy_mode(dsa_to_port(ds, 5)->dn, &interface);
- if (ret && ret != -ENODEV)
- return ret;
} else {
- /* Scan the ethernet nodes. look for GMAC1, lookup used phy */
+ /* Scan the ethernet nodes. Look for GMAC1, lookup the used PHY.
+ * Set priv->p5_intf_sel to the appropriate value if PHY muxing
+ * is detected.
+ */
+ interface = PHY_INTERFACE_MODE_NA;
+
for_each_child_of_node(dn, mac_np) {
if (!of_device_is_compatible(mac_np,
"mediatek,eth-mac"))
@@ -2348,6 +2347,8 @@ mt7530_setup(struct dsa_switch *ds)
of_node_put(phy_node);
break;
}
+
+ mt7530_setup_port5(ds, interface);
}

#ifdef CONFIG_GPIOLIB
@@ -2358,8 +2359,6 @@ mt7530_setup(struct dsa_switch *ds)
}
#endif /* CONFIG_GPIOLIB */

- mt7530_setup_port5(ds, interface);
-
/* Flush the FDB table */
ret = mt7530_fdb_cmd(priv, MT7530_FDB_FLUSH, NULL);
if (ret < 0)

--
2.40.1