ide: add short cables support

This patch allows users to override both host and device side cable detection
with "ideX=ata66" kernel parameter.  Thanks to this it should be now possible
to use UDMA > 2 modes on systems (laptops mainly) which use short 40-pin cable
instead of 80-pin one.

Next patches add automatic detection of some systems using short cables.

Changes:

* Rename hwif->udma_four to hwif->cbl and make it u8.

* Convert all existing users accordingly (use ATA_CBL_* defines while at it).  

* Add ATA_CBL_PATA40_SHORT support to ide-iops.c:eighty_ninty_three().

* Use ATA_CBL_PATA40_SHORT for "ideX=ata66" kernel parameter.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Reviewed-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>

1 files changed, 2 insertions, 3 deletions

diff --git a/drivers/ide/pci/slc90e66.c b/drivers/ide/pci/slc90e66.c
index c40f291f91e0..575dbbd8b482 100644
--- a/drivers/ide/pci/slc90e66.c
+++ b/drivers/ide/pci/slc90e66.c
@@ -199,10 +199,9 @@ static void __devinit init_hwif_slc90e66 (ide_hwif_t *hwif)
         hwif->mwdma_mask = 0x06;
         hwif->swdma_mask = 0x04;
 
-        if (!hwif->udma_four) {
+        if (hwif->cbl != ATA_CBL_PATA40_SHORT)
                 /* bit[0(1)]: 0:80, 1:40 */
-                hwif->udma_four = (reg47 & mask) ? 0 : 1;
-        }
+                hwif->cbl = (reg47 & mask) ? ATA_CBL_PATA40 : ATA_CBL_PATA80;
 
         hwif->ide_dma_check = &slc90e66_config_drive_xfer_rate;