net: phy: consider PHY_IGNORE_INTERRUPT in state machine PHY_NOLINK handling

We can bail out immediately also in case of PHY_IGNORE_INTERRUPT because phy_mac_interupt() informs us once the link is up.

---
 drivers/net/phy/phy.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 05c1e8ef..537297d2 100644
@@ -894,7 +894,7 @@ void phy_state_machine(struct work_struct *work)
 			needs_aneg = true;
 		break;
 	case PHY_NOLINK:
-		if (phy_interrupt_is_valid(phydev))
+		if (phydev->irq != PHY_POLL)
 			break;
 
 		err = phy_read_status(phydev);

2.17.1

From: Heiner Kallweit <[email protected]>
Date: Wed, 30 May 2018 22:13:20 +0200

When state is PHY_NOLINK, the phy_mac_interrupt() code paths will change the state to PHY_CHANGELINK before queueing up the state machine invocation.

So I can't even see how we can enter phy_state_machine with ->state == PHY_NOLINK is the mac interrupt paths are being used properly.

Therefore it looks like the code as written is harmless.

Did you actually hit a problem with this test or is this a change based purely upon code inspection?

We could enter the state machine with PHY_NOLINK in case any other activity triggers a state machine run whilst the link is down. But I'm not sure whether such a scenario exists.

Right, there is no actual problem, the existing code is harmless and the change is just based on code inspection. Small benefit is that it makes clearer that this code path is applicable in polling mode only.

From: Heiner Kallweit <[email protected]>
Date: Wed, 30 May 2018 22:13:20 +0200

Applied, thanks.