summaryrefslogtreecommitdiffstats
path: root/drivers/net/ixgbe/ixgbe_phy.c
diff options
context:
space:
mode:
authorIngo Molnar <mingo@elte.hu>2009-03-28 23:05:50 +0100
committerIngo Molnar <mingo@elte.hu>2009-03-28 23:05:50 +0100
commitb0d44c0dbbd52effb731b1c0af9afd56215c48de (patch)
tree3237c0087d91a5390aed05689b9f610ba16fa116 /drivers/net/ixgbe/ixgbe_phy.c
parent9537a48ed4b9e4b738943d6da0a0fd4278adf905 (diff)
parent7c730ccdc1188b97f5c8cb690906242c7ed75c22 (diff)
Merge branch 'linus' into core/iommu
Conflicts: arch/x86/Kconfig
Diffstat (limited to 'drivers/net/ixgbe/ixgbe_phy.c')
-rw-r--r--drivers/net/ixgbe/ixgbe_phy.c592
1 files changed, 577 insertions, 15 deletions
diff --git a/drivers/net/ixgbe/ixgbe_phy.c b/drivers/net/ixgbe/ixgbe_phy.c
index 5a8669aedf6..14e9606aa3b 100644
--- a/drivers/net/ixgbe/ixgbe_phy.c
+++ b/drivers/net/ixgbe/ixgbe_phy.c
@@ -1,7 +1,7 @@
/*******************************************************************************
Intel 10 Gigabit PCI Express Linux driver
- Copyright(c) 1999 - 2008 Intel Corporation.
+ Copyright(c) 1999 - 2009 Intel Corporation.
This program is free software; you can redistribute it and/or modify it
under the terms and conditions of the GNU General Public License,
@@ -32,6 +32,18 @@
#include "ixgbe_common.h"
#include "ixgbe_phy.h"
+static void ixgbe_i2c_start(struct ixgbe_hw *hw);
+static void ixgbe_i2c_stop(struct ixgbe_hw *hw);
+static s32 ixgbe_clock_in_i2c_byte(struct ixgbe_hw *hw, u8 *data);
+static s32 ixgbe_clock_out_i2c_byte(struct ixgbe_hw *hw, u8 data);
+static s32 ixgbe_get_i2c_ack(struct ixgbe_hw *hw);
+static s32 ixgbe_clock_in_i2c_bit(struct ixgbe_hw *hw, bool *data);
+static s32 ixgbe_clock_out_i2c_bit(struct ixgbe_hw *hw, bool data);
+static s32 ixgbe_raise_i2c_clk(struct ixgbe_hw *hw, u32 *i2cctl);
+static void ixgbe_lower_i2c_clk(struct ixgbe_hw *hw, u32 *i2cctl);
+static s32 ixgbe_set_i2c_data(struct ixgbe_hw *hw, u32 *i2cctl, bool data);
+static bool ixgbe_get_i2c_data(u32 *i2cctl);
+static void ixgbe_i2c_bus_clear(struct ixgbe_hw *hw);
static bool ixgbe_validate_phy_addr(struct ixgbe_hw *hw, u32 phy_addr);
static enum ixgbe_phy_type ixgbe_get_phy_type_from_id(u32 phy_id);
static s32 ixgbe_get_phy_id(struct ixgbe_hw *hw);
@@ -543,8 +555,9 @@ s32 ixgbe_identify_sfp_module_generic(struct ixgbe_hw *hw)
u8 identifier = 0;
u8 comp_codes_1g = 0;
u8 comp_codes_10g = 0;
- u8 oui_bytes[4] = {0, 0, 0, 0};
+ u8 oui_bytes[3] = {0, 0, 0};
u8 transmission_media = 0;
+ u16 enforce_sfp = 0;
status = hw->phy.ops.read_i2c_eeprom(hw, IXGBE_SFF_IDENTIFIER,
&identifier);
@@ -564,18 +577,48 @@ s32 ixgbe_identify_sfp_module_generic(struct ixgbe_hw *hw)
/* ID Module
* =========
- * 0 SFP_DA_CU
- * 1 SFP_SR
- * 2 SFP_LR
+ * 0 SFP_DA_CU
+ * 1 SFP_SR
+ * 2 SFP_LR
+ * 3 SFP_DA_CORE0 - 82599-specific
+ * 4 SFP_DA_CORE1 - 82599-specific
+ * 5 SFP_SR/LR_CORE0 - 82599-specific
+ * 6 SFP_SR/LR_CORE1 - 82599-specific
*/
- if (transmission_media & IXGBE_SFF_TWIN_AX_CAPABLE)
- hw->phy.sfp_type = ixgbe_sfp_type_da_cu;
- else if (comp_codes_10g & IXGBE_SFF_10GBASESR_CAPABLE)
- hw->phy.sfp_type = ixgbe_sfp_type_sr;
- else if (comp_codes_10g & IXGBE_SFF_10GBASELR_CAPABLE)
- hw->phy.sfp_type = ixgbe_sfp_type_lr;
- else
- hw->phy.sfp_type = ixgbe_sfp_type_unknown;
+ if (hw->mac.type == ixgbe_mac_82598EB) {
+ if (transmission_media & IXGBE_SFF_TWIN_AX_CAPABLE)
+ hw->phy.sfp_type = ixgbe_sfp_type_da_cu;
+ else if (comp_codes_10g & IXGBE_SFF_10GBASESR_CAPABLE)
+ hw->phy.sfp_type = ixgbe_sfp_type_sr;
+ else if (comp_codes_10g & IXGBE_SFF_10GBASELR_CAPABLE)
+ hw->phy.sfp_type = ixgbe_sfp_type_lr;
+ else
+ hw->phy.sfp_type = ixgbe_sfp_type_unknown;
+ } else if (hw->mac.type == ixgbe_mac_82599EB) {
+ if (transmission_media & IXGBE_SFF_TWIN_AX_CAPABLE)
+ if (hw->bus.lan_id == 0)
+ hw->phy.sfp_type =
+ ixgbe_sfp_type_da_cu_core0;
+ else
+ hw->phy.sfp_type =
+ ixgbe_sfp_type_da_cu_core1;
+ else if (comp_codes_10g & IXGBE_SFF_10GBASESR_CAPABLE)
+ if (hw->bus.lan_id == 0)
+ hw->phy.sfp_type =
+ ixgbe_sfp_type_srlr_core0;
+ else
+ hw->phy.sfp_type =
+ ixgbe_sfp_type_srlr_core1;
+ else if (comp_codes_10g & IXGBE_SFF_10GBASELR_CAPABLE)
+ if (hw->bus.lan_id == 0)
+ hw->phy.sfp_type =
+ ixgbe_sfp_type_srlr_core0;
+ else
+ hw->phy.sfp_type =
+ ixgbe_sfp_type_srlr_core1;
+ else
+ hw->phy.sfp_type = ixgbe_sfp_type_unknown;
+ }
/* Determine PHY vendor */
if (hw->phy.type == ixgbe_phy_unknown) {
@@ -607,6 +650,9 @@ s32 ixgbe_identify_sfp_module_generic(struct ixgbe_hw *hw)
case IXGBE_SFF_VENDOR_OUI_AVAGO:
hw->phy.type = ixgbe_phy_sfp_avago;
break;
+ case IXGBE_SFF_VENDOR_OUI_INTEL:
+ hw->phy.type = ixgbe_phy_sfp_intel;
+ break;
default:
if (transmission_media &
IXGBE_SFF_TWIN_AX_CAPABLE)
@@ -616,7 +662,28 @@ s32 ixgbe_identify_sfp_module_generic(struct ixgbe_hw *hw)
break;
}
}
- status = 0;
+ if (hw->mac.type == ixgbe_mac_82598EB ||
+ (hw->phy.sfp_type != ixgbe_sfp_type_sr &&
+ hw->phy.sfp_type != ixgbe_sfp_type_lr &&
+ hw->phy.sfp_type != ixgbe_sfp_type_srlr_core0 &&
+ hw->phy.sfp_type != ixgbe_sfp_type_srlr_core1)) {
+ status = 0;
+ goto out;
+ }
+
+ hw->eeprom.ops.read(hw, IXGBE_PHY_ENFORCE_INTEL_SFP_OFFSET,
+ &enforce_sfp);
+ if (!(enforce_sfp & IXGBE_PHY_ALLOW_ANY_SFP)) {
+ /* Make sure we're a supported PHY type */
+ if (hw->phy.type == ixgbe_phy_sfp_intel) {
+ status = 0;
+ } else {
+ hw_dbg(hw, "SFP+ module not supported\n");
+ status = IXGBE_ERR_SFP_NOT_SUPPORTED;
+ }
+ } else {
+ status = 0;
+ }
}
out:
@@ -651,7 +718,7 @@ s32 ixgbe_get_sfp_init_sequence_offsets(struct ixgbe_hw *hw,
hw->eeprom.ops.read(hw, IXGBE_PHY_INIT_OFFSET_NL, list_offset);
if ((!*list_offset) || (*list_offset == 0xFFFF))
- return IXGBE_ERR_PHY;
+ return IXGBE_ERR_SFP_NO_INIT_SEQ_PRESENT;
/* Shift offset to first ID word */
(*list_offset)++;
@@ -688,6 +755,501 @@ s32 ixgbe_get_sfp_init_sequence_offsets(struct ixgbe_hw *hw,
}
/**
+ * ixgbe_read_i2c_eeprom_generic - Reads 8 bit EEPROM word over I2C interface
+ * @hw: pointer to hardware structure
+ * @byte_offset: EEPROM byte offset to read
+ * @eeprom_data: value read
+ *
+ * Performs byte read operation to SFP module's EEPROM over I2C interface.
+ **/
+s32 ixgbe_read_i2c_eeprom_generic(struct ixgbe_hw *hw, u8 byte_offset,
+ u8 *eeprom_data)
+{
+ return hw->phy.ops.read_i2c_byte(hw, byte_offset,
+ IXGBE_I2C_EEPROM_DEV_ADDR,
+ eeprom_data);
+}
+
+/**
+ * ixgbe_write_i2c_eeprom_generic - Writes 8 bit EEPROM word over I2C interface
+ * @hw: pointer to hardware structure
+ * @byte_offset: EEPROM byte offset to write
+ * @eeprom_data: value to write
+ *
+ * Performs byte write operation to SFP module's EEPROM over I2C interface.
+ **/
+s32 ixgbe_write_i2c_eeprom_generic(struct ixgbe_hw *hw, u8 byte_offset,
+ u8 eeprom_data)
+{
+ return hw->phy.ops.write_i2c_byte(hw, byte_offset,
+ IXGBE_I2C_EEPROM_DEV_ADDR,
+ eeprom_data);
+}
+
+/**
+ * ixgbe_read_i2c_byte_generic - Reads 8 bit word over I2C
+ * @hw: pointer to hardware structure
+ * @byte_offset: byte offset to read
+ * @data: value read
+ *
+ * Performs byte read operation to SFP module's EEPROM over I2C interface at
+ * a specified deivce address.
+ **/
+s32 ixgbe_read_i2c_byte_generic(struct ixgbe_hw *hw, u8 byte_offset,
+ u8 dev_addr, u8 *data)
+{
+ s32 status = 0;
+ u32 max_retry = 1;
+ u32 retry = 0;
+ bool nack = 1;
+
+ do {
+ ixgbe_i2c_start(hw);
+
+ /* Device Address and write indication */
+ status = ixgbe_clock_out_i2c_byte(hw, dev_addr);
+ if (status != 0)
+ goto fail;
+
+ status = ixgbe_get_i2c_ack(hw);
+ if (status != 0)
+ goto fail;
+
+ status = ixgbe_clock_out_i2c_byte(hw, byte_offset);
+ if (status != 0)
+ goto fail;
+
+ status = ixgbe_get_i2c_ack(hw);
+ if (status != 0)
+ goto fail;
+
+ ixgbe_i2c_start(hw);
+
+ /* Device Address and read indication */
+ status = ixgbe_clock_out_i2c_byte(hw, (dev_addr | 0x1));
+ if (status != 0)
+ goto fail;
+
+ status = ixgbe_get_i2c_ack(hw);
+ if (status != 0)
+ goto fail;
+
+ status = ixgbe_clock_in_i2c_byte(hw, data);
+ if (status != 0)
+ goto fail;
+
+ status = ixgbe_clock_out_i2c_bit(hw, nack);
+ if (status != 0)
+ goto fail;
+
+ ixgbe_i2c_stop(hw);
+ break;
+
+fail:
+ ixgbe_i2c_bus_clear(hw);
+ retry++;
+ if (retry < max_retry)
+ hw_dbg(hw, "I2C byte read error - Retrying.\n");
+ else
+ hw_dbg(hw, "I2C byte read error.\n");
+
+ } while (retry < max_retry);
+
+ return status;
+}
+
+/**
+ * ixgbe_write_i2c_byte_generic - Writes 8 bit word over I2C
+ * @hw: pointer to hardware structure
+ * @byte_offset: byte offset to write
+ * @data: value to write
+ *
+ * Performs byte write operation to SFP module's EEPROM over I2C interface at
+ * a specified device address.
+ **/
+s32 ixgbe_write_i2c_byte_generic(struct ixgbe_hw *hw, u8 byte_offset,
+ u8 dev_addr, u8 data)
+{
+ s32 status = 0;
+ u32 max_retry = 1;
+ u32 retry = 0;
+
+ do {
+ ixgbe_i2c_start(hw);
+
+ status = ixgbe_clock_out_i2c_byte(hw, dev_addr);
+ if (status != 0)
+ goto fail;
+
+ status = ixgbe_get_i2c_ack(hw);
+ if (status != 0)
+ goto fail;
+
+ status = ixgbe_clock_out_i2c_byte(hw, byte_offset);
+ if (status != 0)
+ goto fail;
+
+ status = ixgbe_get_i2c_ack(hw);
+ if (status != 0)
+ goto fail;
+
+ status = ixgbe_clock_out_i2c_byte(hw, data);
+ if (status != 0)
+ goto fail;
+
+ status = ixgbe_get_i2c_ack(hw);
+ if (status != 0)
+ goto fail;
+
+ ixgbe_i2c_stop(hw);
+ break;
+
+fail:
+ ixgbe_i2c_bus_clear(hw);
+ retry++;
+ if (retry < max_retry)
+ hw_dbg(hw, "I2C byte write error - Retrying.\n");
+ else
+ hw_dbg(hw, "I2C byte write error.\n");
+ } while (retry < max_retry);
+
+ return status;
+}
+
+/**
+ * ixgbe_i2c_start - Sets I2C start condition
+ * @hw: pointer to hardware structure
+ *
+ * Sets I2C start condition (High -> Low on SDA while SCL is High)
+ **/
+static void ixgbe_i2c_start(struct ixgbe_hw *hw)
+{
+ u32 i2cctl = IXGBE_READ_REG(hw, IXGBE_I2CCTL);
+
+ /* Start condition must begin with data and clock high */
+ ixgbe_set_i2c_data(hw, &i2cctl, 1);
+ ixgbe_raise_i2c_clk(hw, &i2cctl);
+
+ /* Setup time for start condition (4.7us) */
+ udelay(IXGBE_I2C_T_SU_STA);
+
+ ixgbe_set_i2c_data(hw, &i2cctl, 0);
+
+ /* Hold time for start condition (4us) */
+ udelay(IXGBE_I2C_T_HD_STA);
+
+ ixgbe_lower_i2c_clk(hw, &i2cctl);
+
+ /* Minimum low period of clock is 4.7 us */
+ udelay(IXGBE_I2C_T_LOW);
+
+}
+
+/**
+ * ixgbe_i2c_stop - Sets I2C stop condition
+ * @hw: pointer to hardware structure
+ *
+ * Sets I2C stop condition (Low -> High on SDA while SCL is High)
+ **/
+static void ixgbe_i2c_stop(struct ixgbe_hw *hw)
+{
+ u32 i2cctl = IXGBE_READ_REG(hw, IXGBE_I2CCTL);
+
+ /* Stop condition must begin with data low and clock high */
+ ixgbe_set_i2c_data(hw, &i2cctl, 0);
+ ixgbe_raise_i2c_clk(hw, &i2cctl);
+
+ /* Setup time for stop condition (4us) */
+ udelay(IXGBE_I2C_T_SU_STO);
+
+ ixgbe_set_i2c_data(hw, &i2cctl, 1);
+
+ /* bus free time between stop and start (4.7us)*/
+ udelay(IXGBE_I2C_T_BUF);
+}
+
+/**
+ * ixgbe_clock_in_i2c_byte - Clocks in one byte via I2C
+ * @hw: pointer to hardware structure
+ * @data: data byte to clock in
+ *
+ * Clocks in one byte data via I2C data/clock
+ **/
+static s32 ixgbe_clock_in_i2c_byte(struct ixgbe_hw *hw, u8 *data)
+{
+ s32 status = 0;
+ s32 i;
+ bool bit = 0;
+
+ for (i = 7; i >= 0; i--) {
+ status = ixgbe_clock_in_i2c_bit(hw, &bit);
+ *data |= bit << i;
+
+ if (status != 0)
+ break;
+ }
+
+ return status;
+}
+
+/**
+ * ixgbe_clock_out_i2c_byte - Clocks out one byte via I2C
+ * @hw: pointer to hardware structure
+ * @data: data byte clocked out
+ *
+ * Clocks out one byte data via I2C data/clock
+ **/
+static s32 ixgbe_clock_out_i2c_byte(struct ixgbe_hw *hw, u8 data)
+{
+ s32 status = 0;
+ s32 i;
+ u32 i2cctl;
+ bool bit = 0;
+
+ for (i = 7; i >= 0; i--) {
+ bit = (data >> i) & 0x1;
+ status = ixgbe_clock_out_i2c_bit(hw, bit);
+
+ if (status != 0)
+ break;
+ }
+
+ /* Release SDA line (set high) */
+ i2cctl = IXGBE_READ_REG(hw, IXGBE_I2CCTL);
+ i2cctl |= IXGBE_I2C_DATA_OUT;
+ IXGBE_WRITE_REG(hw, IXGBE_I2CCTL, i2cctl);
+
+ return status;
+}
+
+/**
+ * ixgbe_get_i2c_ack - Polls for I2C ACK
+ * @hw: pointer to hardware structure
+ *
+ * Clocks in/out one bit via I2C data/clock
+ **/
+static s32 ixgbe_get_i2c_ack(struct ixgbe_hw *hw)
+{
+ s32 status;
+ u32 i = 0;
+ u32 i2cctl = IXGBE_READ_REG(hw, IXGBE_I2CCTL);
+ u32 timeout = 10;
+ bool ack = 1;
+
+ status = ixgbe_raise_i2c_clk(hw, &i2cctl);
+
+ if (status != 0)
+ goto out;
+
+ /* Minimum high period of clock is 4us */
+ udelay(IXGBE_I2C_T_HIGH);
+
+ /* Poll for ACK. Note that ACK in I2C spec is
+ * transition from 1 to 0 */
+ for (i = 0; i < timeout; i++) {
+ i2cctl = IXGBE_READ_REG(hw, IXGBE_I2CCTL);
+ ack = ixgbe_get_i2c_data(&i2cctl);
+
+ udelay(1);
+ if (ack == 0)
+ break;
+ }
+
+ if (ack == 1) {
+ hw_dbg(hw, "I2C ack was not received.\n");
+ status = IXGBE_ERR_I2C;
+ }
+
+ ixgbe_lower_i2c_clk(hw, &i2cctl);
+
+ /* Minimum low period of clock is 4.7 us */
+ udelay(IXGBE_I2C_T_LOW);
+
+out:
+ return status;
+}
+
+/**
+ * ixgbe_clock_in_i2c_bit - Clocks in one bit via I2C data/clock
+ * @hw: pointer to hardware structure
+ * @data: read data value
+ *
+ * Clocks in one bit via I2C data/clock
+ **/
+static s32 ixgbe_clock_in_i2c_bit(struct ixgbe_hw *hw, bool *data)
+{
+ s32 status;
+ u32 i2cctl = IXGBE_READ_REG(hw, IXGBE_I2CCTL);
+
+ status = ixgbe_raise_i2c_clk(hw, &i2cctl);
+
+ /* Minimum high period of clock is 4us */
+ udelay(IXGBE_I2C_T_HIGH);
+
+ i2cctl = IXGBE_READ_REG(hw, IXGBE_I2CCTL);
+ *data = ixgbe_get_i2c_data(&i2cctl);
+
+ ixgbe_lower_i2c_clk(hw, &i2cctl);
+
+ /* Minimum low period of clock is 4.7 us */
+ udelay(IXGBE_I2C_T_LOW);
+
+ return status;
+}
+
+/**
+ * ixgbe_clock_out_i2c_bit - Clocks in/out one bit via I2C data/clock
+ * @hw: pointer to hardware structure
+ * @data: data value to write
+ *
+ * Clocks out one bit via I2C data/clock
+ **/
+static s32 ixgbe_clock_out_i2c_bit(struct ixgbe_hw *hw, bool data)
+{
+ s32 status;
+ u32 i2cctl = IXGBE_READ_REG(hw, IXGBE_I2CCTL);
+
+ status = ixgbe_set_i2c_data(hw, &i2cctl, data);
+ if (status == 0) {
+ status = ixgbe_raise_i2c_clk(hw, &i2cctl);
+
+ /* Minimum high period of clock is 4us */
+ udelay(IXGBE_I2C_T_HIGH);
+
+ ixgbe_lower_i2c_clk(hw, &i2cctl);
+
+ /* Minimum low period of clock is 4.7 us.
+ * This also takes care of the data hold time.
+ */
+ udelay(IXGBE_I2C_T_LOW);
+ } else {
+ status = IXGBE_ERR_I2C;
+ hw_dbg(hw, "I2C data was not set to %X\n", data);
+ }
+
+ return status;
+}
+/**
+ * ixgbe_raise_i2c_clk - Raises the I2C SCL clock
+ * @hw: pointer to hardware structure
+ * @i2cctl: Current value of I2CCTL register
+ *
+ * Raises the I2C clock line '0'->'1'
+ **/
+static s32 ixgbe_raise_i2c_clk(struct ixgbe_hw *hw, u32 *i2cctl)
+{
+ s32 status = 0;
+
+ *i2cctl |= IXGBE_I2C_CLK_OUT;
+
+ IXGBE_WRITE_REG(hw, IXGBE_I2CCTL, *i2cctl);
+
+ /* SCL rise time (1000ns) */
+ udelay(IXGBE_I2C_T_RISE);
+
+ return status;
+}
+
+/**
+ * ixgbe_lower_i2c_clk - Lowers the I2C SCL clock
+ * @hw: pointer to hardware structure
+ * @i2cctl: Current value of I2CCTL register
+ *
+ * Lowers the I2C clock line '1'->'0'
+ **/
+static void ixgbe_lower_i2c_clk(struct ixgbe_hw *hw, u32 *i2cctl)
+{
+
+ *i2cctl &= ~IXGBE_I2C_CLK_OUT;
+
+ IXGBE_WRITE_REG(hw, IXGBE_I2CCTL, *i2cctl);
+
+ /* SCL fall time (300ns) */
+ udelay(IXGBE_I2C_T_FALL);
+}
+
+/**
+ * ixgbe_set_i2c_data - Sets the I2C data bit
+ * @hw: pointer to hardware structure
+ * @i2cctl: Current value of I2CCTL register
+ * @data: I2C data value (0 or 1) to set
+ *
+ * Sets the I2C data bit
+ **/
+static s32 ixgbe_set_i2c_data(struct ixgbe_hw *hw, u32 *i2cctl, bool data)
+{
+ s32 status = 0;
+
+ if (data)
+ *i2cctl |= IXGBE_I2C_DATA_OUT;
+ else
+ *i2cctl &= ~IXGBE_I2C_DATA_OUT;
+
+ IXGBE_WRITE_REG(hw, IXGBE_I2CCTL, *i2cctl);
+
+ /* Data rise/fall (1000ns/300ns) and set-up time (250ns) */
+ udelay(IXGBE_I2C_T_RISE + IXGBE_I2C_T_FALL + IXGBE_I2C_T_SU_DATA);
+
+ /* Verify data was set correctly */
+ *i2cctl = IXGBE_READ_REG(hw, IXGBE_I2CCTL);
+ if (data != ixgbe_get_i2c_data(i2cctl)) {
+ status = IXGBE_ERR_I2C;
+ hw_dbg(hw, "Error - I2C data was not set to %X.\n", data);
+ }
+
+ return status;
+}
+
+/**
+ * ixgbe_get_i2c_data - Reads the I2C SDA data bit
+ * @hw: pointer to hardware structure
+ * @i2cctl: Current value of I2CCTL register
+ *
+ * Returns the I2C data bit value
+ **/
+static bool ixgbe_get_i2c_data(u32 *i2cctl)
+{
+ bool data;
+
+ if (*i2cctl & IXGBE_I2C_DATA_IN)
+ data = 1;
+ else
+ data = 0;
+
+ return data;
+}
+
+/**
+ * ixgbe_i2c_bus_clear - Clears the I2C bus
+ * @hw: pointer to hardware structure
+ *
+ * Clears the I2C bus by sending nine clock pulses.
+ * Used when data line is stuck low.
+ **/
+static void ixgbe_i2c_bus_clear(struct ixgbe_hw *hw)
+{
+ u32 i2cctl = IXGBE_READ_REG(hw, IXGBE_I2CCTL);
+ u32 i;
+
+ ixgbe_set_i2c_data(hw, &i2cctl, 1);
+
+ for (i = 0; i < 9; i++) {
+ ixgbe_raise_i2c_clk(hw, &i2cctl);
+
+ /* Min high period of clock is 4us */
+ udelay(IXGBE_I2C_T_HIGH);
+
+ ixgbe_lower_i2c_clk(hw, &i2cctl);
+
+ /* Min low period of clock is 4.7us*/
+ udelay(IXGBE_I2C_T_LOW);
+ }
+
+ /* Put the i2c bus back to default state */
+ ixgbe_i2c_stop(hw);
+}
+
+/**
* ixgbe_check_phy_link_tnx - Determine link and speed status
* @hw: pointer to hardware structure
*