Commit 6912b712 authored by Russell King's avatar Russell King Committed by David S. Miller
Browse files

net: mdio-i2c: add support for Clause 45 accesses 



Some SFP+ modules have PHYs on them just like SFP modules do, except
they are Clause 45 PHYs.  The I2C protocol used to access them is
modified slightly in order to send the device address and 16-bit
register index.

Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 4882057a

drivers/net/phy/mdio-i2c.c

+20 −8
Original line number Diff line number Diff line
@@ -33,17 +33,24 @@ static int i2c_mii_read(struct mii_bus *bus, int phy_id, int reg) 
{

	struct i2c_adapter *i2c = bus->priv;

	struct i2c_msg msgs[2];

	u8 data[2], dev_addr = reg;

	u8 addr[3], data[2], *p;

	int bus_addr, ret;



	if (!i2c_mii_valid_phy_id(phy_id))

		return 0xffff;



	p = addr;

	if (reg & MII_ADDR_C45) {

		*p++ = 0x20 | ((reg >> 16) & 31);

		*p++ = reg >> 8;

	}

	*p++ = reg;



	bus_addr = i2c_mii_phy_addr(phy_id);

	msgs[0].addr = bus_addr;

	msgs[0].flags = 0;

	msgs[0].len = 1;

	msgs[0].buf = &dev_addr;

	msgs[0].len = p - addr;

	msgs[0].buf = addr;

	msgs[1].addr = bus_addr;

	msgs[1].flags = I2C_M_RD;

	msgs[1].len = sizeof(data);
@@ -61,18 +68,23 @@ static int i2c_mii_write(struct mii_bus *bus, int phy_id, int reg, u16 val) 
	struct i2c_adapter *i2c = bus->priv;

	struct i2c_msg msg;

	int ret;

	u8 data[3];

	u8 data[5], *p;



	if (!i2c_mii_valid_phy_id(phy_id))

		return 0;



	data[0] = reg;

	data[1] = val >> 8;

	data[2] = val;

	p = data;

	if (reg & MII_ADDR_C45) {

		*p++ = (reg >> 16) & 31;

		*p++ = reg >> 8;

	}

	*p++ = reg;

	*p++ = val >> 8;

	*p++ = val;



	msg.addr = i2c_mii_phy_addr(phy_id);

	msg.flags = 0;

	msg.len = 3;

	msg.len = p - data;

	msg.buf = data;



	ret = i2c_transfer(i2c, &msg, 1);

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