[net-next] net: ethernet: adi: adin1110: Fix notifiers

[net-next] net: ethernet: adi: adin1110: Fix notifiers

[Alexandru Tachici]

ADIN1110 was registering netdev_notifiers on each device probe.
This leads to warnings/probe failures because of double registration
of the same notifier when to adin1110/2111 devices are connected to
the same system.

Move the registration of netdev_notifiers in module init call,
in this way multiple driver instances can use the same notifiers.

Fixes: bc93e19d088b ("net: ethernet: adi: Add ADIN1110 support")
Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>
---
 drivers/net/ethernet/adi/adin1110.c | 38 ++++++++++++++++++++++-------
 1 file changed, 29 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/adi/adin1110.c b/drivers/net/ethernet/adi/adin1110.c
index 086aa9c96b31..78ded19dd8c1 100644
--- a/drivers/net/ethernet/adi/adin1110.c
+++ b/drivers/net/ethernet/adi/adin1110.c
@@ -1507,16 +1507,15 @@ static struct notifier_block adin1110_switchdev_notifier = {
 	.notifier_call = adin1110_switchdev_event,
 };
 
-static void adin1110_unregister_notifiers(void *data)
+static void adin1110_unregister_notifiers(void)
 {
 	unregister_switchdev_blocking_notifier(&adin1110_switchdev_blocking_notifier);
 	unregister_switchdev_notifier(&adin1110_switchdev_notifier);
 	unregister_netdevice_notifier(&adin1110_netdevice_nb);
 }
 
-static int adin1110_setup_notifiers(struct adin1110_priv *priv)
+static int adin1110_setup_notifiers(void)
 {
-	struct device *dev = &priv->spidev->dev;
 	int ret;
 
 	ret = register_netdevice_notifier(&adin1110_netdevice_nb);
@@ -1531,13 +1530,14 @@ static int adin1110_setup_notifiers(struct adin1110_priv *priv)
 	if (ret < 0)
 		goto err_sdev;
 
-	return devm_add_action_or_reset(dev, adin1110_unregister_notifiers, NULL);
+	return 0;
 
 err_sdev:
 	unregister_switchdev_notifier(&adin1110_switchdev_notifier);
 
 err_netdev:
 	unregister_netdevice_notifier(&adin1110_netdevice_nb);
+
 	return ret;
 }
 
@@ -1608,10 +1608,6 @@ static int adin1110_probe_netdevs(struct adin1110_priv *priv)
 	if (ret < 0)
 		return ret;
 
-	ret = adin1110_setup_notifiers(priv);
-	if (ret < 0)
-		return ret;
-
 	for (i = 0; i < priv->cfg->ports_nr; i++) {
 		ret = devm_register_netdev(dev, priv->ports[i]->netdev);
 		if (ret < 0) {
@@ -1688,7 +1684,31 @@ static struct spi_driver adin1110_driver = {
 	.probe = adin1110_probe,
 	.id_table = adin1110_spi_id,
 };
-module_spi_driver(adin1110_driver);
+
+static int __init adin1110_driver_init(void)
+{
+	int err;
+
+	err = spi_register_driver(&adin1110_driver);
+	if (err)
+		return err;
+
+	err = adin1110_setup_notifiers();
+	if (err) {
+		spi_unregister_driver(&adin1110_driver);
+		return err;
+	}
+
+	return 0;
+}
+
+static void __exit adin1110_exit(void)
+{
+	adin1110_unregister_notifiers();
+	spi_unregister_driver(&adin1110_driver);
+}
+module_init(adin1110_driver_init);
+module_exit(adin1110_exit);
 
 MODULE_DESCRIPTION("ADIN1110 Network driver");
 MODULE_AUTHOR("Alexandru Tachici <alexandru.tachici@analog.com>");
-- 
2.34.1

Re: [net-next] net: ethernet: adi: adin1110: Fix notifiers

[Jakub Kicinski]

On Wed, 19 Oct 2022 13:17:50 +0300 Alexandru Tachici wrote:
> ADIN1110 was registering netdev_notifiers on each device probe.
> This leads to warnings/probe failures because of double registration
> of the same notifier when to adin1110/2111 devices are connected to
> the same system.
> 
> Move the registration of netdev_notifiers in module init call,
> in this way multiple driver instances can use the same notifiers.
> 
> Fixes: bc93e19d088b ("net: ethernet: adi: Add ADIN1110 support")
> Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>

Could you please repost with [PATCH net] as the subject prefix 
(the change you're fixing has made its way to Linus's tree by now
so you need to target the tree for fixes [1]), and please CC Lennart
since he co-developed the original change.

[1]
https://www.kernel.org/doc/html/next/process/maintainer-netdev.html#how-do-i-indicate-which-tree-net-vs-net-next-my-patch-should-be-in