[PATCH 1/2 v2 net-next] net: phy: provide full set of accessor functions to MMD registers

[Heiner Kallweit <hkallweit1@gmail.com>]

From: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
This adds full set of locked and unlocked accessor functions to read and
write PHY MMD registers and/or bitfields.

Set of functions exactly matches what is already available for PHY
legacy registers.

Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/phy/phy-core.c | 116 ++++++++++++++++++++++++++++----
 include/linux/phy.h        | 134 ++++++++++++++++++++++++++++++-------
 2 files changed, 214 insertions(+), 36 deletions(-)

diff --git a/drivers/net/phy/phy-core.c b/drivers/net/phy/phy-core.c
index 909b3344b..7d6aad287 100644
--- a/drivers/net/phy/phy-core.c
+++ b/drivers/net/phy/phy-core.c
@@ -414,15 +414,15 @@ static void mmd_phy_indirect(struct mii_bus *bus, int phy_addr, int devad,
 }
 
 /**
- * phy_read_mmd - Convenience function for reading a register
+ * __phy_read_mmd - Convenience function for reading a register
  * from an MMD on a given PHY.
  * @phydev: The phy_device struct
  * @devad: The MMD to read from (0..31)
  * @regnum: The register on the MMD to read (0..65535)
  *
- * Same rules as for phy_read();
+ * Same rules as for __phy_read();
  */
-int phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum)
+int __phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum)
 {
 	int val;
 
@@ -434,33 +434,52 @@ int phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum)
 	} else if (phydev->is_c45) {
 		u32 addr = MII_ADDR_C45 | (devad << 16) | (regnum & 0xffff);
 
-		val = mdiobus_read(phydev->mdio.bus, phydev->mdio.addr, addr);
+		val = __mdiobus_read(phydev->mdio.bus, phydev->mdio.addr, addr);
 	} else {
 		struct mii_bus *bus = phydev->mdio.bus;
 		int phy_addr = phydev->mdio.addr;
 
-		mutex_lock(&bus->mdio_lock);
 		mmd_phy_indirect(bus, phy_addr, devad, regnum);
 
 		/* Read the content of the MMD's selected register */
 		val = __mdiobus_read(bus, phy_addr, MII_MMD_DATA);
-		mutex_unlock(&bus->mdio_lock);
 	}
 	return val;
 }
+EXPORT_SYMBOL(__phy_read_mmd);
+
+/**
+ * phy_read_mmd - Convenience function for reading a register
+ * from an MMD on a given PHY.
+ * @phydev: The phy_device struct
+ * @devad: The MMD to read from
+ * @regnum: The register on the MMD to read
+ *
+ * Same rules as for phy_read();
+ */
+int phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum)
+{
+	int ret;
+
+	mutex_lock(&phydev->mdio.bus->mdio_lock);
+	ret = __phy_read_mmd(phydev, devad, regnum);
+	mutex_unlock(&phydev->mdio.bus->mdio_lock);
+
+	return ret;
+}
 EXPORT_SYMBOL(phy_read_mmd);
 
 /**
- * phy_write_mmd - Convenience function for writing a register
+ * __phy_write_mmd - Convenience function for writing a register
  * on an MMD on a given PHY.
  * @phydev: The phy_device struct
  * @devad: The MMD to read from
  * @regnum: The register on the MMD to read
  * @val: value to write to @regnum
  *
- * Same rules as for phy_write();
+ * Same rules as for __phy_write();
  */
-int phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val)
+int __phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val)
 {
 	int ret;
 
@@ -472,23 +491,43 @@ int phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val)
 	} else if (phydev->is_c45) {
 		u32 addr = MII_ADDR_C45 | (devad << 16) | (regnum & 0xffff);
 
-		ret = mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
-				    addr, val);
+		ret = __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
+				      addr, val);
 	} else {
 		struct mii_bus *bus = phydev->mdio.bus;
 		int phy_addr = phydev->mdio.addr;
 
-		mutex_lock(&bus->mdio_lock);
 		mmd_phy_indirect(bus, phy_addr, devad, regnum);
 
 		/* Write the data into MMD's selected register */
 		__mdiobus_write(bus, phy_addr, MII_MMD_DATA, val);
-		mutex_unlock(&bus->mdio_lock);
 
 		ret = 0;
 	}
 	return ret;
 }
+EXPORT_SYMBOL(__phy_write_mmd);
+
+/**
+ * phy_write_mmd - Convenience function for writing a register
+ * on an MMD on a given PHY.
+ * @phydev: The phy_device struct
+ * @devad: The MMD to read from
+ * @regnum: The register on the MMD to read
+ * @val: value to write to @regnum
+ *
+ * Same rules as for phy_write();
+ */
+int phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val)
+{
+	int ret;
+
+	mutex_lock(&phydev->mdio.bus->mdio_lock);
+	ret = __phy_write_mmd(phydev, devad, regnum, val);
+	mutex_unlock(&phydev->mdio.bus->mdio_lock);
+
+	return ret;
+}
 EXPORT_SYMBOL(phy_write_mmd);
 
 /**
@@ -538,6 +577,57 @@ int phy_modify(struct phy_device *phydev, u32 regnum, u16 mask, u16 set)
 }
 EXPORT_SYMBOL_GPL(phy_modify);
 
+/**
+ * __phy_modify_mmd - Convenience function for modifying a register on MMD
+ * @phydev: the phy_device struct
+ * @devad: the MMD containing register to modify
+ * @regnum: register number to modify
+ * @mask: bit mask of bits to clear
+ * @set: new value of bits set in mask to write to @regnum
+ *
+ * Unlocked helper function which allows a MMD register to be modified as
+ * new register value = (old register value & ~mask) | set
+ */
+int __phy_modify_mmd(struct phy_device *phydev, int devad, u32 regnum,
+		     u16 mask, u16 set)
+{
+	int ret;
+
+	ret = __phy_read_mmd(phydev, devad, regnum);
+	if (ret < 0)
+		return ret;
+
+	ret = __phy_write_mmd(phydev, devad, regnum, (ret & ~mask) | set);
+
+	return ret < 0 ? ret : 0;
+}
+EXPORT_SYMBOL_GPL(__phy_modify_mmd);
+
+/**
+ * phy_modify_mmd - Convenience function for modifying a register on MMD
+ * @phydev: the phy_device struct
+ * @devad: the MMD containing register to modify
+ * @regnum: register number to modify
+ * @mask: bit mask of bits to clear
+ * @set: new value of bits set in mask to write to @regnum
+ *
+ * NOTE: MUST NOT be called from interrupt context,
+ * because the bus read/write functions may wait for an interrupt
+ * to conclude the operation.
+ */
+int phy_modify_mmd(struct phy_device *phydev, int devad, u32 regnum,
+		   u16 mask, u16 set)
+{
+	int ret;
+
+	mutex_lock(&phydev->mdio.bus->mdio_lock);
+	ret = __phy_modify_mmd(phydev, devad, regnum, mask, set);
+	mutex_unlock(&phydev->mdio.bus->mdio_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(phy_modify_mmd);
+
 static int __phy_read_page(struct phy_device *phydev)
 {
 	return phydev->drv->read_page(phydev);
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 70f83d0d7..237dd0358 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -692,17 +692,6 @@ static inline bool phy_is_started(struct phy_device *phydev)
 
 void phy_resolve_aneg_linkmode(struct phy_device *phydev);
 
-/**
- * phy_read_mmd - Convenience function for reading a register
- * from an MMD on a given PHY.
- * @phydev: The phy_device struct
- * @devad: The MMD to read from
- * @regnum: The register on the MMD to read
- *
- * Same rules as for phy_read();
- */
-int phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum);
-
 /**
  * phy_read - Convenience function for reading a given PHY register
  * @phydev: the phy_device struct
@@ -758,9 +747,60 @@ static inline int __phy_write(struct phy_device *phydev, u32 regnum, u16 val)
 			       val);
 }
 
+/**
+ * phy_read_mmd - Convenience function for reading a register
+ * from an MMD on a given PHY.
+ * @phydev: The phy_device struct
+ * @devad: The MMD to read from
+ * @regnum: The register on the MMD to read
+ *
+ * Same rules as for phy_read();
+ */
+int phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum);
+
+/**
+ * __phy_read_mmd - Convenience function for reading a register
+ * from an MMD on a given PHY.
+ * @phydev: The phy_device struct
+ * @devad: The MMD to read from
+ * @regnum: The register on the MMD to read
+ *
+ * Same rules as for __phy_read();
+ */
+int __phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum);
+
+/**
+ * phy_write_mmd - Convenience function for writing a register
+ * on an MMD on a given PHY.
+ * @phydev: The phy_device struct
+ * @devad: The MMD to write to
+ * @regnum: The register on the MMD to read
+ * @val: value to write to @regnum
+ *
+ * Same rules as for phy_write();
+ */
+int phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val);
+
+/**
+ * __phy_write_mmd - Convenience function for writing a register
+ * on an MMD on a given PHY.
+ * @phydev: The phy_device struct
+ * @devad: The MMD to write to
+ * @regnum: The register on the MMD to read
+ * @val: value to write to @regnum
+ *
+ * Same rules as for __phy_write();
+ */
+int __phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val);
+
 int __phy_modify(struct phy_device *phydev, u32 regnum, u16 mask, u16 set);
 int phy_modify(struct phy_device *phydev, u32 regnum, u16 mask, u16 set);
 
+int __phy_modify_mmd(struct phy_device *phydev, int devad, u32 regnum,
+		u16 mask, u16 set);
+int phy_modify_mmd(struct phy_device *phydev, int devad, u32 regnum,
+		u16 mask, u16 set);
+
 /**
  * __phy_set_bits - Convenience function for setting bits in a PHY register
  * @phydev: the phy_device struct
@@ -810,6 +850,66 @@ static inline int phy_clear_bits(struct phy_device *phydev, u32 regnum, u16 val)
 	return phy_modify(phydev, regnum, val, 0);
 }
 
+/**
+ * __phy_set_bits_mmd - Convenience function for setting bits in a register
+ * on MMD
+ * @phydev: the phy_device struct
+ * @devad: the MMD containing register to modify
+ * @regnum: register number to modify
+ * @val: bits to set
+ *
+ * The caller must have taken the MDIO bus lock.
+ */
+static inline int __phy_set_bits_mmd(struct phy_device *phydev, int devad,
+		u32 regnum, u16 val)
+{
+	return __phy_modify_mmd(phydev, devad, regnum, 0, val);
+}
+
+/**
+ * __phy_clear_bits_mmd - Convenience function for clearing bits in a register
+ * on MMD
+ * @phydev: the phy_device struct
+ * @devad: the MMD containing register to modify
+ * @regnum: register number to modify
+ * @val: bits to clear
+ *
+ * The caller must have taken the MDIO bus lock.
+ */
+static inline int __phy_clear_bits_mmd(struct phy_device *phydev, int devad,
+		u32 regnum, u16 val)
+{
+	return __phy_modify_mmd(phydev, devad, regnum, val, 0);
+}
+
+/**
+ * phy_set_bits_mmd - Convenience function for setting bits in a register
+ * on MMD
+ * @phydev: the phy_device struct
+ * @devad: the MMD containing register to modify
+ * @regnum: register number to modify
+ * @val: bits to set
+ */
+static inline int phy_set_bits_mmd(struct phy_device *phydev, int devad,
+		u32 regnum, u16 val)
+{
+	return phy_modify_mmd(phydev, devad, regnum, 0, val);
+}
+
+/**
+ * phy_clear_bits_mmd - Convenience function for clearing bits in a register
+ * on MMD
+ * @phydev: the phy_device struct
+ * @devad: the MMD containing register to modify
+ * @regnum: register number to modify
+ * @val: bits to clear
+ */
+static inline int phy_clear_bits_mmd(struct phy_device *phydev, int devad,
+		u32 regnum, u16 val)
+{
+	return phy_modify_mmd(phydev, devad, regnum, val, 0);
+}
+
 /**
  * phy_interrupt_is_valid - Convenience function for testing a given PHY irq
  * @phydev: the phy_device struct
@@ -886,18 +986,6 @@ static inline bool phy_is_pseudo_fixed_link(struct phy_device *phydev)
 	return phydev->is_pseudo_fixed_link;
 }
 
-/**
- * phy_write_mmd - Convenience function for writing a register
- * on an MMD on a given PHY.
- * @phydev: The phy_device struct
- * @devad: The MMD to read from
- * @regnum: The register on the MMD to read
- * @val: value to write to @regnum
- *
- * Same rules as for phy_write();
- */
-int phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val);
-
 int phy_save_page(struct phy_device *phydev);
 int phy_select_page(struct phy_device *phydev, int page);
 int phy_restore_page(struct phy_device *phydev, int oldpage, int ret);
-- 
2.20.1