diff mbox series

[v2,net,1/5] net: mdio: introduce a shutdown method to mdio device drivers

Message ID 20210917133436.553995-2-vladimir.oltean@nxp.com (mailing list archive)
State New, archived
Headers show
Series Make DSA switch drivers compatible with masters which unregister on shutdown | expand

Commit Message

Vladimir Oltean Sept. 17, 2021, 1:34 p.m. UTC 
MDIO-attached devices might have interrupts and other things that might
need quiesced when we kexec into a new kernel. Things are even more
creepy when those interrupt lines are shared, and in that case it is
absolutely mandatory to disable all interrupt sources.

Moreover, MDIO devices might be DSA switches, and DSA needs its own
shutdown method to unlink from the DSA master, which is a new
requirement that appeared after commit 2f1e8ea726e9 ("net: dsa: link
interfaces with the DSA master to get rid of lockdep warnings").

So introduce a ->shutdown method in the MDIO device driver structure.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
---
 drivers/net/phy/mdio_device.c | 11 +++++++++++
 include/linux/mdio.h          |  3 +++
 2 files changed, 14 insertions(+)
diff mbox series

Patch

diff --git a/drivers/net/phy/mdio_device.c b/drivers/net/phy/mdio_device.c
index c94cb5382dc9..250742ffdfd9 100644
--- a/drivers/net/phy/mdio_device.c
+++ b/drivers/net/phy/mdio_device.c
@@ -179,6 +179,16 @@  static int mdio_remove(struct device *dev)
 	return 0;
 }
 
+static void mdio_shutdown(struct device *dev)
+{
+	struct mdio_device *mdiodev = to_mdio_device(dev);
+	struct device_driver *drv = mdiodev->dev.driver;
+	struct mdio_driver *mdiodrv = to_mdio_driver(drv);
+
+	if (mdiodrv->shutdown)
+		mdiodrv->shutdown(mdiodev);
+}
+
 /**
  * mdio_driver_register - register an mdio_driver with the MDIO layer
  * @drv: new mdio_driver to register
@@ -193,6 +203,7 @@  int mdio_driver_register(struct mdio_driver *drv)
 	mdiodrv->driver.bus = &mdio_bus_type;
 	mdiodrv->driver.probe = mdio_probe;
 	mdiodrv->driver.remove = mdio_remove;
+	mdiodrv->driver.shutdown = mdio_shutdown;
 
 	retval = driver_register(&mdiodrv->driver);
 	if (retval) {
diff --git a/include/linux/mdio.h b/include/linux/mdio.h
index ffb787d5ebde..5e6dc38f418e 100644
--- a/include/linux/mdio.h
+++ b/include/linux/mdio.h
@@ -80,6 +80,9 @@  struct mdio_driver {
 
 	/* Clears up any memory if needed */
 	void (*remove)(struct mdio_device *mdiodev);
+
+	/* Quiesces the device on system shutdown, turns off interrupts etc */
+	void (*shutdown)(struct mdio_device *mdiodev);
 };
 
 static inline struct mdio_driver *