Commit 38f961e7 authored by Heiner Kallweit's avatar Heiner Kallweit Committed by David S. Miller
Browse files

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: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 4406d36d

drivers/net/phy/mdio_bus.c

+7 −1
Original line number Diff line number Diff line
@@ -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);

	}

include/linux/phy.h

+17 −0
Original line number Diff line number Diff line
@@ -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);

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