> What if the netdev does not have a PHY? The MAC also has speed
> information.
The ethtool API provides a list of link modes the MAC supports:
/usr/sbin/ethtool enp2s0
Settings for enp2s0:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
The MAC driver can provide this information by calling into phylib or
phylink, or it can do it some other way. In fact, none of the LED code
goes direct to the PHY when determining when to blink in software, its
all via the struct net_device.
We should use the ethtool API to determine which speed sysfs files
should exist.
Andrew
