ide: make ide_rate_filter() also respect PIO and SW/MW DMA mode masks

Make ide_rate_filter() also respect PIO/SWDMA/MWDMA mode masks. While at it, make the udma_filter() method calls take precedence over using the mode masks.

---
This version doesn't use explicit UltraDMA masks, so converting them to the ATA_UDMA* is left for another, global patch. This patch against the current Linus' tree and unfortunately I was able to only compile test it since that tree gives MODPOST warning and dies early on bootup.

 drivers/ide/ide-dma.c |    7 +++--
 drivers/ide/ide-lib.c |   65 +++++++++++++++++++++++++++++++++-----------------
 2 files changed, 47 insertions(+), 25 deletions(-)

Index: linux-2.6/drivers/ide/ide-dma.c
===================================================================
@@ -664,10 +664,11 @@ static unsigned int ide_get_mode_mask(id
 		if ((id->field_valid & 4) == 0)
 			break;
 
-		mask = id->dma_ultra & hwif->ultra_mask;
-
 		if (hwif->udma_filter)
-			mask &= hwif->udma_filter(drive);
+			mask = hwif->udma_filter(drive);
+		else
+			mask = hwif->ultra_mask;
+		mask &= id->dma_ultra;
 
 		if ((mask & 0x78) && (eighty_ninty_three(drive) == 0))
 			mask &= 0x07;

Argh, ignore the above sentense.

This is still so. I'll try to test it whenever I have enought time...

MBR, Sergei