setting up connman to manage a single preferred connection

Question

I have a device that has both ethernet and wifi adapters. I'm trying to use connman to manage my connections. I'd like it to connect to ethernet when it's available and fallback to wifi if there's no ethernet connection.

Here's my /etc/connman/main.conf:

[General]
PreferredTechnologies=ethernet,wifi
SingleConnectedTechnology=true

What does work:

• if I have the ethernet connected when the device turns on it properly establishes a connection
• if I use connmanctl to manually connect to the wifi it will properly switch off the ethernet connection and switch over to the wifi connection

What does not work:

• if the device is started up with no ethernet cable then wifi is not established
• if the device was started up and connected to the ethernet then disconnecting the cable does not cause the wifi to connect
• if the device is started up and then the ethernet cable is connected later, it does not connect to the ethernet automatically

I'm using connman 1.15

EDIT:

• /sys/class/net/eth0/carrier doesn't seem to detect the change in cable connection
• ip monitor does seem to be able to detect when the cable is connected or disconnected

Answer 1

It seems like the issue is with the PHY driver. The output of mii-tool eth0 is No MII transceiver present!. indicating it's not working properly. The strange thing is I did have it going at one point and then it stopped again without any changes being made to the driver or kernel. I suspect there's some sort of bug in the driver. The PHYceiver in question is the ICplus 101A and I tried the latest linux driver in both the 3.4 and mainline (backported to 3.4) branches.