diff options
| author | Don Skidmore <donald.c.skidmore@intel.com> | 2012-03-15 07:36:37 +0000 |
|---|---|---|
| committer | Jeff Kirsher <jeffrey.t.kirsher@intel.com> | 2012-04-14 02:10:50 -0700 |
| commit | 8f56e4b9ab72109c5bf6d3e32ff43321a3ba4386 (patch) | |
| tree | 255b2e4a6bce0d3e9b19391abd21da86383879a6 | |
| parent | be0c0068140dea329d151be58b8fdd9fa22301ca (diff) | |
ixgbe: add I2C clock stretching
This patch adds support for I2C clock stretching which is required per
SFF-8636. Customers with passive DA cables implement clock stretching
would fail without this patch.
Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
| -rw-r--r-- | drivers/net/ethernet/intel/ixgbe/ixgbe_phy.c | 20 | ||||
| -rw-r--r-- | drivers/net/ethernet/intel/ixgbe/ixgbe_type.h | 1 |
2 files changed, 15 insertions, 6 deletions
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_phy.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_phy.c index bf9f82f4b1ae..24117709d6a2 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_phy.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_phy.c @@ -1582,13 +1582,21 @@ static s32 ixgbe_clock_out_i2c_bit(struct ixgbe_hw *hw, bool data) **/ static void ixgbe_raise_i2c_clk(struct ixgbe_hw *hw, u32 *i2cctl) { - *i2cctl |= IXGBE_I2C_CLK_OUT; - - IXGBE_WRITE_REG(hw, IXGBE_I2CCTL, *i2cctl); - IXGBE_WRITE_FLUSH(hw); + u32 i = 0; + u32 timeout = IXGBE_I2C_CLOCK_STRETCHING_TIMEOUT; + u32 i2cctl_r = 0; - /* SCL rise time (1000ns) */ - udelay(IXGBE_I2C_T_RISE); + for (i = 0; i < timeout; i++) { + *i2cctl |= IXGBE_I2C_CLK_OUT; + IXGBE_WRITE_REG(hw, IXGBE_I2CCTL, *i2cctl); + IXGBE_WRITE_FLUSH(hw); + /* SCL rise time (1000ns) */ + udelay(IXGBE_I2C_T_RISE); + + i2cctl_r = IXGBE_READ_REG(hw, IXGBE_I2CCTL); + if (i2cctl_r & IXGBE_I2C_CLK_IN) + break; + } } /** diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h index ffa6679e943b..4acd9e665b28 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h @@ -110,6 +110,7 @@ #define IXGBE_I2C_CLK_OUT 0x00000002 #define IXGBE_I2C_DATA_IN 0x00000004 #define IXGBE_I2C_DATA_OUT 0x00000008 +#define IXGBE_I2C_CLOCK_STRETCHING_TIMEOUT 500 /* Interrupt Registers */ #define IXGBE_EICR 0x00800 |