In musb_init_controller() there's a pm_runtime_put(), but there's no
pm_runtime_get(), which creates a mismatch that causes the driver to
sleep when it shouldn't.
This was introduced in 7acc619, but it wasn't triggered until 18a2689
was merged to Linus' branch at point 6899608.
However, it seems most of the time this is used in a way that keeps the
counter above 0, so nobody noticed. Also, it seems to depend on the
configuration used.
I found the problem by loading isp1704_charger before any usb gadgets:
http://article.gmane.org/gmane.linux.kernel/1226122
All versions after 2.6.39 are affected.
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Felipe Contreras<felipe.contreras@xxxxxxxxx>