Paul Fertser

Using i.MX25's integrated UTMI PHY in device mode without Vbus

Discussion created by Paul Fertser on Oct 21, 2011
Latest reply on Mar 6, 2013 by Charles Powe


We're planning to use our custom board with i.MX25 in USB device mode but unfortunately we haven't routed out the Vbus pin so here goes my question:

What is needed to actually put the integrated OTG controller in device mode and to start communication? I've disabled the vbus handling logic and made sure the RUN_STOP bit is unset but i still can't see a pull-up on a USB data line, so no communication is possible.

Using upstream kernel here of course.

The documentation about the integrated UTMI PHY seems to be lacking in this regard, so can anybody please enlighten me?