Commit 63490847 authored by Michael Walle's avatar Michael Walle Committed by David S. Miller
Browse files

net: phy: add concept of shared storage for PHYs 



There are packages which contain multiple PHY devices, eg. a quad PHY
transceiver. Provide functions to allocate and free shared storage.

Usually, a quad PHY contains global registers, which don't belong to any
PHY. Provide convenience functions to access these registers.

Signed-off-by: default avatarMichael Walle <michael@walle.cc>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Reviewed-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 857b4125

drivers/net/phy/mdio_bus.c

+1 −0
Original line number Diff line number Diff line
@@ -614,6 +614,7 @@ int __mdiobus_register(struct mii_bus *bus, struct module *owner) 
	}



	mutex_init(&bus->mdio_lock);

	mutex_init(&bus->shared_lock);



	/* de-assert bus level PHY GPIO reset */

	gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_LOW);

drivers/net/phy/phy_device.c

+138 −0
Original line number Diff line number Diff line
@@ -1461,6 +1461,144 @@ bool phy_driver_is_genphy_10g(struct phy_device *phydev) 
}

EXPORT_SYMBOL_GPL(phy_driver_is_genphy_10g);



/**

 * phy_package_join - join a common PHY group

 * @phydev: target phy_device struct

 * @addr: cookie and PHY address for global register access

 * @priv_size: if non-zero allocate this amount of bytes for private data

 *

 * This joins a PHY group and provides a shared storage for all phydevs in

 * this group. This is intended to be used for packages which contain

 * more than one PHY, for example a quad PHY transceiver.

 *

 * The addr parameter serves as a cookie which has to have the same value

 * for all members of one group and as a PHY address to access generic

 * registers of a PHY package. Usually, one of the PHY addresses of the

 * different PHYs in the package provides access to these global registers.

 * The address which is given here, will be used in the phy_package_read()

 * and phy_package_write() convenience functions. If your PHY doesn't have

 * global registers you can just pick any of the PHY addresses.

 *

 * This will set the shared pointer of the phydev to the shared storage.

 * If this is the first call for a this cookie the shared storage will be

 * allocated. If priv_size is non-zero, the given amount of bytes are

 * allocated for the priv member.

 *

 * Returns < 1 on error, 0 on success. Esp. calling phy_package_join()

 * with the same cookie but a different priv_size is an error.

 */

int phy_package_join(struct phy_device *phydev, int addr, size_t priv_size)

{

	struct mii_bus *bus = phydev->mdio.bus;

	struct phy_package_shared *shared;

	int ret;



	if (addr < 0 || addr >= PHY_MAX_ADDR)

		return -EINVAL;



	mutex_lock(&bus->shared_lock);

	shared = bus->shared[addr];

	if (!shared) {

		ret = -ENOMEM;

		shared = kzalloc(sizeof(*shared), GFP_KERNEL);

		if (!shared)

			goto err_unlock;

		if (priv_size) {

			shared->priv = kzalloc(priv_size, GFP_KERNEL);

			if (!shared->priv)

				goto err_free;

			shared->priv_size = priv_size;

		}

		shared->addr = addr;

		refcount_set(&shared->refcnt, 1);

		bus->shared[addr] = shared;

	} else {

		ret = -EINVAL;

		if (priv_size && priv_size != shared->priv_size)

			goto err_unlock;

		refcount_inc(&shared->refcnt);

	}

	mutex_unlock(&bus->shared_lock);



	phydev->shared = shared;



	return 0;



err_free:

	kfree(shared);

err_unlock:

	mutex_unlock(&bus->shared_lock);

	return ret;

}

EXPORT_SYMBOL_GPL(phy_package_join);



/**

 * phy_package_leave - leave a common PHY group

 * @phydev: target phy_device struct

 *

 * This leaves a PHY group created by phy_package_join(). If this phydev

 * was the last user of the shared data between the group, this data is

 * freed. Resets the phydev->shared pointer to NULL.

 */

void phy_package_leave(struct phy_device *phydev)

{

	struct phy_package_shared *shared = phydev->shared;

	struct mii_bus *bus = phydev->mdio.bus;



	if (!shared)

		return;



	if (refcount_dec_and_mutex_lock(&shared->refcnt, &bus->shared_lock)) {

		bus->shared[shared->addr] = NULL;

		mutex_unlock(&bus->shared_lock);

		kfree(shared->priv);

		kfree(shared);

	}



	phydev->shared = NULL;

}

EXPORT_SYMBOL_GPL(phy_package_leave);



static void devm_phy_package_leave(struct device *dev, void *res)

{

	phy_package_leave(*(struct phy_device **)res);

}



/**

 * devm_phy_package_join - resource managed phy_package_join()

 * @dev: device that is registering this PHY package

 * @phydev: target phy_device struct

 * @addr: cookie and PHY address for global register access

 * @priv_size: if non-zero allocate this amount of bytes for private data

 *

 * Managed phy_package_join(). Shared storage fetched by this function,

 * phy_package_leave() is automatically called on driver detach. See

 * phy_package_join() for more information.

 */

int devm_phy_package_join(struct device *dev, struct phy_device *phydev,

			  int addr, size_t priv_size)

{

	struct phy_device **ptr;

	int ret;



	ptr = devres_alloc(devm_phy_package_leave, sizeof(*ptr),

			   GFP_KERNEL);

	if (!ptr)

		return -ENOMEM;



	ret = phy_package_join(phydev, addr, priv_size);



	if (!ret) {

		*ptr = phydev;

		devres_add(dev, ptr);

	} else {

		devres_free(ptr);

	}



	return ret;

}

EXPORT_SYMBOL_GPL(devm_phy_package_join);



/**

 * phy_detach - detach a PHY device from its network device

 * @phydev: target phy_device struct

include/linux/phy.h

+89 −0
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include <linux/u64_stats_sync.h>

#include <linux/irqreturn.h>

#include <linux/iopoll.h>

#include <linux/refcount.h>



#include <linux/atomic.h>
@@ -227,6 +228,28 @@ struct mdio_bus_stats { 
	struct u64_stats_sync syncp;

};



/* Represents a shared structure between different phydev's in the same

 * package, for example a quad PHY. See phy_package_join() and

 * phy_package_leave().

 */

struct phy_package_shared {

	int addr;

	refcount_t refcnt;

	unsigned long flags;

	size_t priv_size;



	/* private data pointer */

	/* note that this pointer is shared between different phydevs and

	 * the user has to take care of appropriate locking. It is allocated

	 * and freed automatically by phy_package_join() and

	 * phy_package_leave().

	 */

	void *priv;

};



/* used as bit number in atomic bitops */

#define PHY_SHARED_F_INIT_DONE 0



/*

 * The Bus class for PHYs.  Devices which provide access to

 * PHYs should register using this structure
@@ -278,6 +301,12 @@ struct mii_bus { 
	int reset_delay_us;

	/* RESET GPIO descriptor pointer */

	struct gpio_desc *reset_gpiod;



	/* protect access to the shared element */

	struct mutex shared_lock;



	/* shared state across different PHYs */

	struct phy_package_shared *shared[PHY_MAX_ADDR];

};

#define to_mii_bus(d) container_of(d, struct mii_bus, dev)
@@ -478,6 +507,10 @@ struct phy_device { 
	/* For use by PHYs to maintain extra state */

	void *priv;



	/* shared data pointer */

	/* For use by PHYs inside the same package that need a shared state. */

	struct phy_package_shared *shared;



	/* Interrupt and Polling infrastructure */

	struct delayed_work state_queue;
@@ -1354,6 +1387,10 @@ int phy_ethtool_get_link_ksettings(struct net_device *ndev, 
int phy_ethtool_set_link_ksettings(struct net_device *ndev,

				   const struct ethtool_link_ksettings *cmd);

int phy_ethtool_nway_reset(struct net_device *ndev);

int phy_package_join(struct phy_device *phydev, int addr, size_t priv_size);

void phy_package_leave(struct phy_device *phydev);

int devm_phy_package_join(struct device *dev, struct phy_device *phydev,

			  int addr, size_t priv_size);



#if IS_ENABLED(CONFIG_PHYLIB)

int __init mdio_bus_init(void);
@@ -1406,6 +1443,58 @@ static inline int phy_ethtool_get_stats(struct phy_device *phydev, 
	return 0;

}



static inline int phy_package_read(struct phy_device *phydev, u32 regnum)

{

	struct phy_package_shared *shared = phydev->shared;



	if (!shared)

		return -EIO;



	return mdiobus_read(phydev->mdio.bus, shared->addr, regnum);

}



static inline int __phy_package_read(struct phy_device *phydev, u32 regnum)

{

	struct phy_package_shared *shared = phydev->shared;



	if (!shared)

		return -EIO;



	return __mdiobus_read(phydev->mdio.bus, shared->addr, regnum);

}



static inline int phy_package_write(struct phy_device *phydev,

				    u32 regnum, u16 val)

{

	struct phy_package_shared *shared = phydev->shared;



	if (!shared)

		return -EIO;



	return mdiobus_write(phydev->mdio.bus, shared->addr, regnum, val);

}



static inline int __phy_package_write(struct phy_device *phydev,

				      u32 regnum, u16 val)

{

	struct phy_package_shared *shared = phydev->shared;



	if (!shared)

		return -EIO;



	return __mdiobus_write(phydev->mdio.bus, shared->addr, regnum, val);

}



static inline bool phy_package_init_once(struct phy_device *phydev)

{

	struct phy_package_shared *shared = phydev->shared;



	if (!shared)

		return false;



	return !test_and_set_bit(PHY_SHARED_F_INIT_DONE, &shared->flags);

}



extern struct bus_type mdio_bus_type;



struct mdio_board_info {

CRA Git | Maintained and supported by SUSTech CRA and CCSE