From 34dc08e4be208539b7c4aa8154a610e1736705e8 Mon Sep 17 00:00:00 2001 From: Russell King Date: Tue, 2 Jan 2018 10:58:27 +0000 Subject: [PATCH] net: mdiobus: add unlocked accessors Add unlocked versions of the bus accessors, which allows access to the bus with all the tracing. These accessors validate that the bus mutex is held, which is a basic requirement for all mii bus accesses. Reviewed-by: Florian Fainelli Signed-off-by: Russell King Signed-off-by: David S. Miller --- drivers/net/phy/mdio_bus.c | 65 +++++++++++++++++++++++++++++++------- include/linux/mdio.h | 3 ++ 2 files changed, 56 insertions(+), 12 deletions(-) diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c index a0f34c385cad..e2419c792a44 100644 --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -514,6 +514,55 @@ struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr) } EXPORT_SYMBOL(mdiobus_scan); +/** + * __mdiobus_read - Unlocked version of the mdiobus_read function + * @bus: the mii_bus struct + * @addr: the phy address + * @regnum: register number to read + * + * Read a MDIO bus register. Caller must hold the mdio bus lock. + * + * NOTE: MUST NOT be called from interrupt context. + */ +int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum) +{ + int retval; + + WARN_ON_ONCE(!mutex_is_locked(&bus->mdio_lock)); + + retval = bus->read(bus, addr, regnum); + + trace_mdio_access(bus, 1, addr, regnum, retval, retval); + + return retval; +} +EXPORT_SYMBOL(__mdiobus_read); + +/** + * __mdiobus_write - Unlocked version of the mdiobus_write function + * @bus: the mii_bus struct + * @addr: the phy address + * @regnum: register number to write + * @val: value to write to @regnum + * + * Write a MDIO bus register. Caller must hold the mdio bus lock. + * + * NOTE: MUST NOT be called from interrupt context. + */ +int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val) +{ + int err; + + WARN_ON_ONCE(!mutex_is_locked(&bus->mdio_lock)); + + err = bus->write(bus, addr, regnum, val); + + trace_mdio_access(bus, 0, addr, regnum, val, err); + + return err; +} +EXPORT_SYMBOL(__mdiobus_write); + /** * mdiobus_read_nested - Nested version of the mdiobus_read function * @bus: the mii_bus struct @@ -534,11 +583,9 @@ int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum) BUG_ON(in_interrupt()); mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED); - retval = bus->read(bus, addr, regnum); + retval = __mdiobus_read(bus, addr, regnum); mutex_unlock(&bus->mdio_lock); - trace_mdio_access(bus, 1, addr, regnum, retval, retval); - return retval; } EXPORT_SYMBOL(mdiobus_read_nested); @@ -560,11 +607,9 @@ int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum) BUG_ON(in_interrupt()); mutex_lock(&bus->mdio_lock); - retval = bus->read(bus, addr, regnum); + retval = __mdiobus_read(bus, addr, regnum); mutex_unlock(&bus->mdio_lock); - trace_mdio_access(bus, 1, addr, regnum, retval, retval); - return retval; } EXPORT_SYMBOL(mdiobus_read); @@ -590,11 +635,9 @@ int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val) BUG_ON(in_interrupt()); mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED); - err = bus->write(bus, addr, regnum, val); + err = __mdiobus_write(bus, addr, regnum, val); mutex_unlock(&bus->mdio_lock); - trace_mdio_access(bus, 0, addr, regnum, val, err); - return err; } EXPORT_SYMBOL(mdiobus_write_nested); @@ -617,11 +660,9 @@ int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val) BUG_ON(in_interrupt()); mutex_lock(&bus->mdio_lock); - err = bus->write(bus, addr, regnum, val); + err = __mdiobus_write(bus, addr, regnum, val); mutex_unlock(&bus->mdio_lock); - trace_mdio_access(bus, 0, addr, regnum, val, err); - return err; } EXPORT_SYMBOL(mdiobus_write); diff --git a/include/linux/mdio.h b/include/linux/mdio.h index 268aad47ecd3..2cfffe586885 100644 --- a/include/linux/mdio.h +++ b/include/linux/mdio.h @@ -262,6 +262,9 @@ static inline u16 ethtool_adv_to_mmd_eee_adv_t(u32 adv) return reg; } +int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum); +int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val); + int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum); int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum); int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val);