[PATCH AUTOSEL 4.19 209/258] igb: Fix an issue that PME is not enabled during runtime suspend

From: Sasha Levin
Date: Mon Jan 28 2019 - 11:09:29 EST


From: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>

[ Upstream commit 1fb3a7a75e2efcc83ef21f2434069cddd6fae6f5 ]

I210 ethernet card doesn't wakeup when a cable gets plugged. It's
because its PME is not set.

Since commit 42eca2302146 ("PCI: Don't touch card regs after runtime
suspend D3"), if the PCI state is saved, pci_pm_runtime_suspend() stops
calling pci_finish_runtime_suspend(), which enables the PCI PME.

To fix the issue, let's not to save PCI states when it's runtime
suspend, to let the PCI subsystem enables PME.

Fixes: 42eca2302146 ("PCI: Don't touch card regs after runtime suspend D3")
Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
Tested-by: Aaron Brown <aaron.f.brown@xxxxxxxxx>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/intel/igb/igb_main.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index 0796cef96fa3..ffaa6e031632 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -8770,9 +8770,11 @@ static int __igb_shutdown(struct pci_dev *pdev, bool *enable_wake,
rtnl_unlock();

#ifdef CONFIG_PM
- retval = pci_save_state(pdev);
- if (retval)
- return retval;
+ if (!runtime) {
+ retval = pci_save_state(pdev);
+ if (retval)
+ return retval;
+ }
#endif

status = rd32(E1000_STATUS);
--
2.19.1