ixgbe: add write flush in ixgbe_clock_out_i2c_byte()

I2C access is timing critical. Always do a write flush after writing
to the I2CCTL register.

(cherry picked from commit 176f950d310c81b7fafd96aabe53704f778ce269)
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Joe Jin <joe.jin@oracle.com>

diff --git a/drivers/net/ixgbe/ixgbe_phy.c b/drivers/net/ixgbe/ixgbe_phy.c
index 9a56fd74e6738f5a16beb7b2c95c75ccc619e366..70d7856969460e477574cc460810680e406967f8 100644 (file)
--- a/drivers/net/ixgbe/ixgbe_phy.c
+++ b/drivers/net/ixgbe/ixgbe_phy.c
@@ -1457,6 +1457,7 @@ static s32 ixgbe_clock_out_i2c_byte(struct ixgbe_hw *hw, u8 data)
        i2cctl = IXGBE_READ_REG(hw, IXGBE_I2CCTL);
        i2cctl |= IXGBE_I2C_DATA_OUT;
        IXGBE_WRITE_REG(hw, IXGBE_I2CCTL, i2cctl);
+       IXGBE_WRITE_FLUSH(hw);
 
        return status;
 }