From 44aaee6ec8a2e0bce92d40229ef55c3b4adc6769 Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Mon, 20 Apr 2020 23:29:05 +0200 Subject: [PATCH] net: phy: add device-managed devm_mdiobus_register If there's no special ordering requirement for mdiobus_unregister(), then driver code can be simplified by using a device-managed version of mdiobus_register(). Prerequisite is that bus allocation has been done device-managed too. Else mdiobus_free() may be called whilst bus is still registered, resulting in a BUG_ON(). Therefore let devm_mdiobus_register() return -EPERM if bus was allocated non-managed. Signed-off-by: Heiner Kallweit Signed-off-by: David S. Miller --- drivers/net/phy/mdio_bus.c | 8 +++++++- include/linux/phy.h | 17 +++++++++++++++++ 2 files changed, 24 insertions(+), 1 deletion(-) diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c index 346e88435d296..26b00af945737 100644 --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -170,7 +170,12 @@ EXPORT_SYMBOL(mdiobus_alloc_size); static void _devm_mdiobus_free(struct device *dev, void *res) { - mdiobus_free(*(struct mii_bus **)res); + struct mii_bus *bus = *(struct mii_bus **)res; + + if (bus->is_managed_registered && bus->state == MDIOBUS_REGISTERED) + mdiobus_unregister(bus); + + mdiobus_free(bus); } static int devm_mdiobus_match(struct device *dev, void *res, void *data) @@ -210,6 +215,7 @@ struct mii_bus *devm_mdiobus_alloc_size(struct device *dev, int sizeof_priv) if (bus) { *ptr = bus; devres_add(dev, ptr); + bus->is_managed = 1; } else { devres_free(ptr); } diff --git a/include/linux/phy.h b/include/linux/phy.h index 2432ca463ddc0..3941a6bcba101 100644 --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -241,6 +241,9 @@ struct mii_bus { int (*reset)(struct mii_bus *bus); struct mdio_bus_stats stats[PHY_MAX_ADDR]; + unsigned int is_managed:1; /* is device-managed */ + unsigned int is_managed_registered:1; + /* * A lock to ensure that only one thing can read/write * the MDIO bus at a time @@ -286,6 +289,20 @@ static inline struct mii_bus *mdiobus_alloc(void) int __mdiobus_register(struct mii_bus *bus, struct module *owner); #define mdiobus_register(bus) __mdiobus_register(bus, THIS_MODULE) +static inline int devm_mdiobus_register(struct mii_bus *bus) +{ + int ret; + + if (!bus->is_managed) + return -EPERM; + + ret = mdiobus_register(bus); + if (!ret) + bus->is_managed_registered = 1; + + return ret; +} + void mdiobus_unregister(struct mii_bus *bus); void mdiobus_free(struct mii_bus *bus); struct mii_bus *devm_mdiobus_alloc_size(struct device *dev, int sizeof_priv); -- 2.39.5