e1000e: 82579 intermittently disabled during S0->Sx

When repeatedly cycling Sx->S0 states with the network cable unplugged,
the 82579 PHY may not initialize as expected and may require a full power
cycle to recover functionality to the device.  Workaround this by testing
access of the PHY registers after resuming; if that returns unexpected
results toggle the LANPHYPC signal to power cycle the PHY.

This is implemented in the new function e1000_resume_workarounds_pchlan()
which calls another new function, e1000_toggle_lanphypc_value_ich8lan(),
which has been created to reduce code duplication (same functionality
required by a previous workaround).  Also, e1000e_disable_gig_wol_ich8lan
is now e1000_suspend_workarounds_ich8lan to better reflect what it does.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c
index 888bd9cc2710..c4a23c7ac170 100644
--- a/drivers/net/e1000e/netdev.c
+++ b/drivers/net/e1000e/netdev.c
@@ -5278,7 +5278,7 @@ static int __e1000_shutdown(struct pci_dev *pdev, bool *enable_wake,
                 }
 
                 if (adapter->flags & FLAG_IS_ICH)
-                        e1000e_disable_gig_wol_ich8lan(&adapter->hw);
+                        e1000_suspend_workarounds_ich8lan(&adapter->hw);
 
                 /* Allow time for pending master requests to run */
                 e1000e_disable_pcie_master(&adapter->hw);
@@ -5429,6 +5429,9 @@ static int __e1000_resume(struct pci_dev *pdev)
                         return err;
         }
 
+        if (hw->mac.type == e1000_pch2lan)
+                e1000_resume_workarounds_pchlan(&adapter->hw);
+
         e1000e_power_up_phy(adapter);
 
         /* report the system wakeup cause from S3/S4 */