igc: Change type of the 'igc_check_downshift' method

The 'igc_check_downshift' method always returns 0; there is no need
for a return value so change the type of this method to void.
Signed-off-by: Sasha Neftin <sasha.neftin@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/igc/igc_phy.c

@@ -141,18 +141,14 @@ void igc_power_down_phy_copper(struct igc_hw *hw)
  * igc_check_downshift - Checks whether a downshift in speed occurred
  * @hw: pointer to the HW structure
  *
- * Success returns 0, Failure returns 1
- *
  * A downshift is detected by querying the PHY link health.
  */
-s32 igc_check_downshift(struct igc_hw *hw)
+void igc_check_downshift(struct igc_hw *hw)
 {
 	struct igc_phy_info *phy = &hw->phy;
 
 	/* speed downshift not supported */
 	phy->speed_downgraded = false;
-
-	return 0;
 }
 
 /**

drivers/net/ethernet/intel/igc/igc_phy.h

@@ -11,7 +11,7 @@ s32 igc_phy_hw_reset(struct igc_hw *hw);
 s32 igc_get_phy_id(struct igc_hw *hw);
 s32 igc_phy_has_link(struct igc_hw *hw, u32 iterations,
 		     u32 usec_interval, bool *success);
-s32 igc_check_downshift(struct igc_hw *hw);
+void igc_check_downshift(struct igc_hw *hw);
 s32 igc_setup_copper_link(struct igc_hw *hw);
 void igc_power_up_phy_copper(struct igc_hw *hw);
 void igc_power_down_phy_copper(struct igc_hw *hw);