All read transactions initiated by firedtv are only quadlet-sized, hence
the backend->read call can be simplified a little.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Packet DMA buffers are queued either initially all at once (then, a
queueing failure will cause firedtv to release the DMA context as a
whole) or subsequently one by one as they recycled after use (then a
failure is extremely unlikely).  Therefore we can be a little less
cautious when counting at which packet buffer to set the interrupt flag.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Cache only addresses of whole pages, not of each buffer chunk.  Besides,
page addresses can be obtained by page_address() instead of kmap() since
they were allocated in lowmem.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The firedtv DVB driver will now work not only on top of the old ieee1394
driver stack but also on the new firewire driver stack.

Alongside to the firedtv-1394.c backend for driver binding and I/O, the
firedtv-fw.c backend is added.  Depending on which of the two 1394
stacks is configured, one or the other or both backends will be built
into the firedtv driver.

This has been tested with a DVB-T and a DVB-C box on x86-64 and x86-32
together with a few different controllers (Agere FW323, a NEC chip, TI
TSB82AA2, TSB43AB22/A, VIA VT6306).
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>