Excerpts from Martin Pieuchot's message of 2014-11-20 02:30:44 -0800: > I don't know how it works in Apple machines but other people reported > such weird thing with machine having an xhci(4)/ehci(4) controller. > Telling the BIOS to "deactivate" USB 3 support made their ports work > again with ehci(4), do you have a way to do that on your MacbookAir5,1?
I tried the ways I've heard of for forcing my MacbookAir5,1 into EHCI mode, but they did not work: https://gist.github.com/jcs/5573685 I tried both variations of the OSX bless command that jcs suggests: sudo bless --device /dev/disk1 --setBoot --legacy sudo bless --device /dev/disk1 --setBoot --nextonly --legacy Neither of them results in external USB ports that work. After running bless, I booted (*without* holding down the alt key, so as to let the bless command take effect) to 5.6-release-amd64 bsd.rd and plugged in a USB device into an external port, but nothing shows up on the screen indicating a device was just plugged in and the lights on the device itself don't light up, in contrast to the behavior on 5.5-stable where after plugging the same device into the same USB port, text appears on the screen and the lights on the device itself light up.
