diff options
author | Michael Walle <michael@walle.cc> | 2020-05-06 17:53:13 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2020-05-07 00:53:29 +0300 |
commit | 6349084746ff4f5f7ebc748e4b2a890f8c57b129 (patch) | |
tree | 81102a5bf8f322a83df5f15d2ca1f9cfd8accafa | |
parent | 857b412511c87ed7137e63b90b2de020c24660e9 (diff) | |
download | linux-6349084746ff4f5f7ebc748e4b2a890f8c57b129.tar.xz |
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: Michael Walle <michael@walle.cc>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | drivers/net/phy/mdio_bus.c | 1 | ||||
-rw-r--r-- | drivers/net/phy/phy_device.c | 138 | ||||
-rw-r--r-- | include/linux/phy.h | 89 |
3 files changed, 228 insertions, 0 deletions
diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c index 3e79b96fa344..255fdfcc13a6 100644 --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -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); diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 7e1ddd5745d2..b1c5e4503bc4 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -1462,6 +1462,144 @@ 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 * diff --git a/include/linux/phy.h b/include/linux/phy.h index e2bfb9240587..1d36ac608159 100644 --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -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 { |