- In uhci_intr() check to see if sc->sc_bus.bdev is NULL, and if it is,
ack any pending interrupts and disable them, then return. It is possible
for interrupts to be delivered the moment a handler is set up at attach
time in uhci_pci.c, particularly when attempting to kldload the usb.ko
module after the system is already up. However the driver isn't ready
to field interrupts at that time and certain pointers in the softc
struct aren't initialized yet, and we invariably end up falling off
the end of one of them. The effect is that kldloading the usb module
will panic the system in uhci_intr(). This added sanity check stops
this from happening: I can now kldload the usb.ko module without any
problems and load/attach other USB drivers after it.
Of course the uhci driver has no detach method, but that's another
problem.
- In uhci_run(), set the UHCI_CMD_MAXP bit in the command register to
allow 64-byte packets to be used for full speed bandwidth reclamation.
Certain high speed devices (in this case the ADMtek USB ethernet
adapter) require this bit to be set, otherwise babble errors occur
at the end of large (between 1100 and 1500 byte) transfers. This
should not affect other devices, although supposedly it is less efficient
than the 32-byte setting. Unfortunately, this is a per-bus setting,
not a per-device setting, so we can't just enable it for certain
devices on the USB bus.
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