From 6912b712cd75aaa1c8d90b291ec7d2504f17f263 Mon Sep 17 00:00:00 2001 From: Russell King Date: Wed, 11 Dec 2019 10:56:20 +0000 Subject: [PATCH] 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: Andrew Lunn Signed-off-by: Russell King Signed-off-by: David S. Miller --- drivers/net/phy/mdio-i2c.c | 28 ++++++++++++++++++++-------- 1 file changed, 20 insertions(+), 8 deletions(-) diff --git a/drivers/net/phy/mdio-i2c.c b/drivers/net/phy/mdio-i2c.c index 0dce67672548..0746e2cc39ae 100644 --- a/drivers/net/phy/mdio-i2c.c +++ b/drivers/net/phy/mdio-i2c.c @@ -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); -- 2.30.2