I have a small experimental change to /sys/src/9/pc/usbohci.c which
is needed to get my macbook's built-in bluetooth working with Plan 9
under virtualbox.  As a pleasing side effect, it speeds up reading of
usb1.0 flash disks by about a factor of ten.

Before submitting a patch I want to check that it also works on native
Plan 9, but I don't have suitable hardware.  Would someone running
native Plan 9 on a motherboard with an ohci host adapter like to help,
by building a kernel with the usbohci.c from /n/sources/contrib/miller,
testing that any usb1.0 devices still work, and measuring usb disk speed
before and after with something like:
  time dd -if /dev/sdU0.0/data -of /dev/null -bs 64k -count 16

Note that usb2.0 devices should not be affected by the change, because
they will be handled by the usbehci.c driver.  You can use usb/probe
to check which usb driver (uhci, ohci, ehci) is handling each plugged-in
device.

In theory you can force usb2.0 devices to be handled by ohci as well,
by setting *nousbehci=1 in plan9.ini to disable the ehci driver.  This
doesn't work for me on virtualbox (which gets thoroughly wedged when I
attach a usb2.0 flash drive), but it might work on real hardware.


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