From a41938d07201d0e7793f5aade5574a49f32ae82f Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Fri, 17 Sep 2021 16:34:32 +0300 Subject: [PATCH] net: mdio: introduce a shutdown method to mdio device drivers [ Upstream commit cf9579976f724ad517cc15b7caadea728c7e245c ] 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 Reviewed-by: Andrew Lunn Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/phy/mdio_device.c | 11 +++++++++++ include/linux/mdio.h | 3 +++ 2 files changed, 14 insertions(+) diff --git a/drivers/net/phy/mdio_device.c b/drivers/net/phy/mdio_device.c index 0837319a52d7..797c41f5590e 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 dbd69b3d170b..de5fb4b333ce 100644 --- a/include/linux/mdio.h +++ b/include/linux/mdio.h @@ -72,6 +72,9 @@ 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); }; #define to_mdio_driver(d) \ container_of(to_mdio_common_driver(d), struct mdio_driver, mdiodrv)