kernel: fix DSA mac_select_pcs backport

Backport commit from Linux 5.18 fixing phylink with DSA drivers which
do not provide mac_select_pcs yet.

Fixes: aab466f422 ("kernel: backport generic phylink validate")
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
This commit is contained in:
Daniel Golle 2022-09-01 21:40:44 +01:00
parent 90f55f5bf1
commit 6c302b9009

View File

@ -0,0 +1,88 @@
From 1054457006d4a14de4ae4132030e33d7eedaeba1 Mon Sep 17 00:00:00 2001
From: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>
Date: Mon, 21 Feb 2022 17:10:52 +0000
Subject: [PATCH] net: phy: phylink: fix DSA mac_select_pcs() introduction
Vladimir Oltean reports that probing on DSA drivers that aren't yet
populating supported_interfaces now fails. Fix this by allowing
phylink to detect whether DSA actually provides an underlying
mac_select_pcs() implementation.
Reported-by: Vladimir Oltean <olteanv@gmail.com>
Fixes: bde018222c6b ("net: dsa: add support for phylink mac_select_pcs()")
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/E1nMCD6-00A0wC-FG@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
drivers/net/phy/phylink.c | 14 +++++++++++---
net/dsa/port.c | 2 +-
2 files changed, 12 insertions(+), 4 deletions(-)
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -74,6 +74,7 @@ struct phylink {
struct work_struct resolve;
bool mac_link_dropped;
+ bool using_mac_select_pcs;
struct sfp_bus *sfp_bus;
bool sfp_may_have_phy;
@@ -163,7 +164,7 @@ static int phylink_validate_mac_and_pcs(
int ret;
/* Get the PCS for this interface mode */
- if (pl->mac_ops->mac_select_pcs) {
+ if (pl->using_mac_select_pcs) {
pcs = pl->mac_ops->mac_select_pcs(pl->config, state->interface);
if (IS_ERR(pcs))
return PTR_ERR(pcs);
@@ -790,7 +791,7 @@ static void phylink_major_config(struct
phylink_dbg(pl, "major config %s\n", phy_modes(state->interface));
- if (pl->mac_ops->mac_select_pcs) {
+ if (pl->using_mac_select_pcs) {
pcs = pl->mac_ops->mac_select_pcs(pl->config, state->interface);
if (IS_ERR(pcs)) {
phylink_err(pl,
@@ -1192,11 +1193,17 @@ struct phylink *phylink_create(struct ph
phy_interface_t iface,
const struct phylink_mac_ops *mac_ops)
{
+ bool using_mac_select_pcs = false;
struct phylink *pl;
int ret;
- /* Validate the supplied configuration */
if (mac_ops->mac_select_pcs &&
+ mac_ops->mac_select_pcs(config, PHY_INTERFACE_MODE_NA) !=
+ ERR_PTR(-EOPNOTSUPP))
+ using_mac_select_pcs = true;
+
+ /* Validate the supplied configuration */
+ if (using_mac_select_pcs &&
phy_interface_empty(config->supported_interfaces)) {
dev_err(config->dev,
"phylink: error: empty supported_interfaces but mac_select_pcs() method present\n");
@@ -1220,6 +1227,7 @@ struct phylink *phylink_create(struct ph
return ERR_PTR(-EINVAL);
}
+ pl->using_mac_select_pcs = using_mac_select_pcs;
pl->phy_state.interface = iface;
pl->link_interface = iface;
if (iface == PHY_INTERFACE_MODE_MOCA)
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -1017,8 +1017,8 @@ dsa_port_phylink_mac_select_pcs(struct p
phy_interface_t interface)
{
struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
+ struct phylink_pcs *pcs = ERR_PTR(-EOPNOTSUPP);
struct dsa_switch *ds = dp->ds;
- struct phylink_pcs *pcs = NULL;
if (ds->ops->phylink_mac_select_pcs)
pcs = ds->ops->phylink_mac_select_pcs(ds, dp->index, interface);