diff options
Diffstat (limited to 'drivers/net/mdio/mdio-i2c.c')
| -rw-r--r-- | drivers/net/mdio/mdio-i2c.c | 79 |
1 files changed, 78 insertions, 1 deletions
diff --git a/drivers/net/mdio/mdio-i2c.c b/drivers/net/mdio/mdio-i2c.c index da2001ea1f99..53e96bfab542 100644 --- a/drivers/net/mdio/mdio-i2c.c +++ b/drivers/net/mdio/mdio-i2c.c @@ -106,6 +106,62 @@ static int i2c_mii_write_default_c22(struct mii_bus *bus, int phy_id, int reg, return i2c_mii_write_default_c45(bus, phy_id, -1, reg, val); } +static int smbus_byte_mii_read_default_c22(struct mii_bus *bus, int phy_id, + int reg) +{ + struct i2c_adapter *i2c = bus->priv; + union i2c_smbus_data smbus_data; + int val = 0, ret; + + if (!i2c_mii_valid_phy_id(phy_id)) + return 0; + + ret = i2c_smbus_xfer(i2c, i2c_mii_phy_addr(phy_id), 0, + I2C_SMBUS_READ, reg, + I2C_SMBUS_BYTE_DATA, &smbus_data); + if (ret < 0) + return ret; + + val = (smbus_data.byte & 0xff) << 8; + + ret = i2c_smbus_xfer(i2c, i2c_mii_phy_addr(phy_id), 0, + I2C_SMBUS_READ, reg, + I2C_SMBUS_BYTE_DATA, &smbus_data); + if (ret < 0) + return ret; + + val |= smbus_data.byte & 0xff; + + return val; +} + +static int smbus_byte_mii_write_default_c22(struct mii_bus *bus, int phy_id, + int reg, u16 val) +{ + struct i2c_adapter *i2c = bus->priv; + union i2c_smbus_data smbus_data; + int ret; + + if (!i2c_mii_valid_phy_id(phy_id)) + return 0; + + smbus_data.byte = (val & 0xff00) >> 8; + + ret = i2c_smbus_xfer(i2c, i2c_mii_phy_addr(phy_id), 0, + I2C_SMBUS_WRITE, reg, + I2C_SMBUS_BYTE_DATA, &smbus_data); + if (ret < 0) + return ret; + + smbus_data.byte = val & 0xff; + + ret = i2c_smbus_xfer(i2c, i2c_mii_phy_addr(phy_id), 0, + I2C_SMBUS_WRITE, reg, + I2C_SMBUS_BYTE_DATA, &smbus_data); + + return ret < 0 ? ret : 0; +} + /* RollBall SFPs do not access internal PHY via I2C address 0x56, but * instead via address 0x51, when SFP page is set to 0x03 and password to * 0xffffffff. @@ -378,13 +434,26 @@ static int i2c_mii_init_rollball(struct i2c_adapter *i2c) return 0; } +static bool mdio_i2c_check_functionality(struct i2c_adapter *i2c, + enum mdio_i2c_proto protocol) +{ + if (i2c_check_functionality(i2c, I2C_FUNC_I2C)) + return true; + + if (i2c_check_functionality(i2c, I2C_FUNC_SMBUS_BYTE_DATA) && + protocol == MDIO_I2C_MARVELL_C22) + return true; + + return false; +} + struct mii_bus *mdio_i2c_alloc(struct device *parent, struct i2c_adapter *i2c, enum mdio_i2c_proto protocol) { struct mii_bus *mii; int ret; - if (!i2c_check_functionality(i2c, I2C_FUNC_I2C)) + if (!mdio_i2c_check_functionality(i2c, protocol)) return ERR_PTR(-EINVAL); mii = mdiobus_alloc(); @@ -395,6 +464,14 @@ struct mii_bus *mdio_i2c_alloc(struct device *parent, struct i2c_adapter *i2c, mii->parent = parent; mii->priv = i2c; + /* Only use SMBus if we have no other choice */ + if (i2c_check_functionality(i2c, I2C_FUNC_SMBUS_BYTE_DATA) && + !i2c_check_functionality(i2c, I2C_FUNC_I2C)) { + mii->read = smbus_byte_mii_read_default_c22; + mii->write = smbus_byte_mii_write_default_c22; + return mii; + } + switch (protocol) { case MDIO_I2C_ROLLBALL: ret = i2c_mii_init_rollball(i2c); |