In chronological order, here are some recent changes I've made:

 - Implement bus space access and extent maps.  This allows drivers
   to easily map address space and mark it as `in use' so that other
   drivers won't grab it (if they also use this code).

 - Update the asc driver (Apple Sound Chip) to use the bus space access
   code.

 - Implement a /dev/asc* device, which gives the user direct access to the 
   ASC's buffers and registers via the mmap(2) system call.  Simply open()
   the /dev/asc0 device and use mmap() to bring it into the process'
   address space.

 - Divorce the ite (console terminal emulator) and the asc devices from on
   another.  NOTE:  Now that the asc driver is completely optional, you
   must specify it in your kernel config file if you wish to retain the
   console beep when using the ite.

 - Allow the use of an `addr' locator for the asc driver, e.g.:

	asc0 at obio0 addr 0x5f014000

   to hard-wire the ASC at physical address 0x5f014000 (which is,
   indidentally, the default address).

Expect more changes of this sort to be coming down the pike, as I'm
cleaning up driver attachments to address some Duo-related issues (which
at first glance had appeared to be minor!).

--scott