New USB driver & API (updated)
Hans Petter Selasky
hselasky at c2i.net
Sun Sep 18 10:32:54 PDT 2005
I have just updated my USB driver for FreeBSD 5/6/7.
Download the three files below into a new directory and type
"make install" (to uninstall type "make deinstall")
Type "make help" to get more help.
I have included a patch for "uaudio.c" that will allow "full duplex" to work.
This time I have added two refcounts to each "struct usbd_xfer". The one
refcount keeps track of the number of threads that are holding a reference to
it, and is decremented when memory is freed. The other refcount keeps track
of the number of re-starts, and is incremented when a USB transfer is
stopped. For example see "ehci_pcd_enable()" in "/sys/dev/usb2/_ehci.c" and
"usbd_do_callback()" in "/sys/dev/usb2/_usb.c". This is almost like in
Stopping and starting a transfer does not block or sleep, which means one can
hold a lock while doing this. I have added a callback, search for
"priv_func", that will be called just before the USB transfer memory is
freed. This can be used for mutex destruction purposes, and alike.
I want to use "callout_init_mtx()", but I am not sure when this was
introduced, and to not break this driver on older versions of FreeBSD, I
still use "callout_init()". But this is just a matter of a few one-liners.
I have done an great deal of work on "ugen" and it should now support BULK-,
INTERRUPT- and ISOCHRONOUS- transfers in read and write direction. If you are
interested, you can have a look at: "/sys/dev/usb2/_ugen.c"
More information about the freebsd-multimedia