[Intel-wired-lan] [bug report] igc: Add code for PHY support

[Dan Carpenter]

Hello Sasha Neftin,

The patch 5586838fe9ce: "igc: Add code for PHY support" from Oct 11,
2018, leads to the following static checker warning:

	drivers/net/ethernet/intel/igc/igc_phy.c:167 igc_check_downshift()
	info: ignoring unreachable code.

drivers/net/ethernet/intel/igc/igc_phy.c
   144  /**
   145   * igc_check_downshift - Checks whether a downshift in speed occurred
   146   * @hw: pointer to the HW structure
   147   *
   148   * Success returns 0, Failure returns 1
   149   *
   150   * A downshift is detected by querying the PHY link health.
   151   */
   152  s32 igc_check_downshift(struct igc_hw *hw)
   153  {
   154          struct igc_phy_info *phy = &hw->phy;
   155          u16 phy_data, offset, mask;
   156          s32 ret_val;
   157  
   158          switch (phy->type) {
   159          case igc_phy_i225:
   160          default:
   161                  /* speed downshift not supported */
   162                  phy->speed_downgraded = false;
   163                  ret_val = 0;
   164                  goto out;
                        ^^^^^^^^^
We always say it's not supported.

   165          }
   166  
   167          ret_val = phy->ops.read_reg(hw, offset, &phy_data);
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
unreachable.

   168  
   169          if (!ret_val)
   170                  phy->speed_downgraded = (phy_data & mask) ? true : false;
   171  
   172  out:
   173          return ret_val;
   174  }

regards,
dan carpenter