Fix a number of issues with the DMA support code:

- driver claims support for all SW/MW DMA modes while supporting only MWDMA2;

- ide_dma_check() method tries to enable DMA on the "known good" drives which
  don't support MWDMA2;

- ide_dma_on() method upon failure to set drive to MWDMA2 re-tunes already
  tuned PIO mode and calls ide_dma_off() method instead of returning error;

- ide_dma_off() method sets drive->current_speed while it doesn't actually
  change (only the PIO timings are re-loaded into the chip's registers);

- init_hwif() method forcibly sets/resets both "drive DMA capable" bits while
  this is properly handled by ide_dma_{on,off}() methods being called later...
Signed-off-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

also change __devinit tag for sgiioc4.c:ioc4_ide_init() to __init
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Straighten up the IDE control/status register caching -- you *really* can't
cache the shared register per-channel and hope that it won't get out ouf
sync.

Set the PIO fallback mode to PIO0 for the slave drive as well as master --
there was no point in having them different (most probably a resutl of
typo).

Do a bit of reformat and cleanup while at it...
Signed-off-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Acked-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NJörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>

Move auto arrays to static (const).  Clean up using PCI_DEVICE in places,
remove unreachable junk and dead code.

Fix the serverworks cable detect logic (if ordering is wrong).  Backport
from libata.  Plenty of scope for more cleanup left.
Signed-off-by: NAlan Cox <alan@redhat.com>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We don't want to reset the DMA state machine while the other
channel is in use.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

We must _never_ _ever_ on pain of death enable IDE DMA on SL82C105
chipsets where the southbridge revision is <= 5, otherwise data
corruption will occur.

Strangely this used to work, but something has changed in the upper
echelons of the IDE layer to break the hosts decision to deny DMA.
Let's make it crystal clear to the IDE layer that we know best.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

From: Herbert Xu <herbert@gondor.apana.org.au>

mark the __init section __devinit.
Splitted up from the Debian kernel patch.
Signed-off-by: Nmaximilian attems <janitor@sternwelten.at>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@elka.pw.edu.pl>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!