Hi everyone, I know it's a bit late for this post but...
I tried rico999 solution and I just do it!!
I have had some problems but finally I have my b85m-itx working with OMV and WOL.
I will try to help others telling my experience.
1. First of all, a short class of history. Here is the commit where WOL was removed from alx drivers because PC restarted when you try to suspend:
If you look at the log: https://git.kernel.org/cgit/linux/ke...et/atheros/alx
you can see al the changes have been made to the alx drivers. You can think it's not useful but you will be mistaken.
2. People having troubles with 'SET_ETHTOOL_OPS'. Looking at the log you can see that 2 months ago someone changes the line where the error is coming.
All you have to do is to edit the main.c file and change that line manully, it's just one line, don't be lazy.
Later I will try to look if other changes could help too. But for now I will leave the driver and see if it works correctly.
After compiling as rico999:
make -C /lib/modules/$(uname -r)/build M=$(pwd) modules
make -C /lib/modules/$(uname -r)/build M=$(pwd) modules_install
rm /lib/modules/$(uname -r)/kernel/drivers/net/ethernet/atheros/alx/alx.ko
cp alx.ko /lib/modules/$(uname -r)/kernel/drivers/net/ethernet/atheros/alx/alx.ko
you have your drivers with WOL.
I almost gave up trying to make my system to get the new drivers on boot. I tried everything but it looked imposible, I follow rico999 steps and it didn't work so I go slowly.
First I saw if the drivers worked deleting actual and inserting new.
insmod alx.ko #From alx compiled driver folder
Then to test: "ethtool -s eth0 wol g" and no out was given! Before the insert the system said wol wasn't supported.
So drivers works. For now I don't know exactly what I do to make my system get the new drivers, I tried rico999 advice a lot of times, lot of reboots, depmod command, but after all I get it, in one of that probes I poweroff and the ethernet light was on!!
Don't give up and good luck!