eth: mcux: Do not set carrier ON if interface is not known

[jukkar]

It is possible that the network interface is not yet resolved
when status of the PHY changes. In this case we must not call
net_eth_carrier_on() as that will cause a crash.
This was noticed with mimxrt1050_evk board.

Fixes: #21257

Signed-off-by: Jukka Rissanen jukka.rissanen@linux.intel.com

[pfalcon]

Can you please clarify what "network interface is not yet resolved" means?

[jukkar]

Can you please clarify what "network interface is not yet resolved" means?

Basically it means that eth_iface_init() has not been called yet, as that will set/resolve the context->iface = iface; which is used by eth_mcux_phy_event(). So basically we get a PHY event while the driver is being setup and interface is still NULL. This is probably something to do with timing of the system. Also indicated in other PRs, the mimxrt1050_evk is faster than k64f and I have not seen this error when using k64f.

[pfalcon]

@jukkar: Thanks for explanation. My question was mostly a "first reading question", where a stumbled upon "network interface is not yet resolved" as unfamiliar wording which got me confusing. E.g. I've heard about "address not yet resolved", but don't remember hearing it in regard to interface. Your comment explains it, but I wonder if it would make sense to say "network interface is not yet initialized" or "network interface pointer [in context?] is not yet initialize". Or if you think that description captures the situation well, I'll just note it for the future.

[jukkar]

if it would make sense to say "network interface is not yet initialized" or "network interface pointer [in context?] is not yet initialize". Or if you think that description captures the situation well, I'll just note it for the future.

Sure, you suggestion makes sense. I will rephrase the sentence.

[agansari]

@jukkar i'm not sure about the 1ms sleep, i added that as a delay between mii commands, i need to check what it's for

[jukkar]

i'm not sure about the 1ms sleep, i added that as a delay between mii commands, i need to check what it's for

Please submit another PR if you find the sleep unnecessary.