net: phy: Add nested variants of mdiobus read/write (21dd19fe) · Commits · 戴 / test

drivers/net/phy/mdio_bus.c

+55 −0

Original line number	Diff line number	Diff line
		@@ -371,6 +371,33 @@ struct phy_device mdiobus_scan(struct mii_bus bus, int addr)
		}
		EXPORT_SYMBOL(mdiobus_scan);

		/**
		* mdiobus_read_nested - Nested version of the mdiobus_read function
		* @bus: the mii_bus struct
		* @addr: the phy address
		* @regnum: register number to read
		*
		* In case of nested MDIO bus access avoid lockdep false positives by
		* using mutex_lock_nested().
		*
		* NOTE: MUST NOT be called from interrupt context,
		* because the bus read/write functions may wait for an interrupt
		* to conclude the operation.
		*/
		int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum)
		{
		int retval;

		BUG_ON(in_interrupt());

		mutex_lock_nested(&bus->mdio_lock, SINGLE_DEPTH_NESTING);
		retval = bus->read(bus, addr, regnum);
		mutex_unlock(&bus->mdio_lock);

		return retval;
		}
		EXPORT_SYMBOL(mdiobus_read_nested);

		/**
		* mdiobus_read - Convenience function for reading a given MII mgmt register
		* @bus: the mii_bus struct
		@@ -395,6 +422,34 @@ int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
		}
		EXPORT_SYMBOL(mdiobus_read);

		/**
		* mdiobus_write_nested - Nested 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
		*
		* In case of nested MDIO bus access avoid lockdep false positives by
		* using mutex_lock_nested().
		*
		* NOTE: MUST NOT be called from interrupt context,
		* because the bus read/write functions may wait for an interrupt
		* to conclude the operation.
		*/
		int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val)
		{
		int err;

		BUG_ON(in_interrupt());

		mutex_lock_nested(&bus->mdio_lock, SINGLE_DEPTH_NESTING);
		err = bus->write(bus, addr, regnum, val);
		mutex_unlock(&bus->mdio_lock);

		return err;
		}
		EXPORT_SYMBOL(mdiobus_write_nested);

		/**
		* mdiobus_write - Convenience function for writing a given MII mgmt register
		* @bus: the mii_bus struct

include/linux/phy.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -213,7 +213,9 @@ static inline struct mii_bus devm_mdiobus_alloc(struct device dev)
		void devm_mdiobus_free(struct device dev, struct mii_bus bus);
		struct phy_device mdiobus_scan(struct mii_bus bus, int addr);
		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);
		int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val);


		#define PHY_INTERRUPT_DISABLED 0x0

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