[PATCH] PIIX/SLC90E66: PIO mode fallback fix

The fallback to PIO mode in the hwif->dma_check() handler doesn't work in
the Intel PIIX and SMsC SLC90E66 IDE drivers because:

- config_drive_for_dma() calls the hwif->speedproc() handler with a wrong
  mode number (unbiased by XFER_PIO_0) in case of the PIO fallback;

- hwif->tuneproc() handler doesn't really set the drive's own speed (this
  is not fixed as yet).

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 9 insertions, 11 deletions

diff --git a/drivers/ide/pci/slc90e66.c b/drivers/ide/pci/slc90e66.c
index 4a1853af3bbb..9be7e49cba0e 100644
--- a/drivers/ide/pci/slc90e66.c
+++ b/drivers/ide/pci/slc90e66.c
@@ -1,9 +1,10 @@
 /*
- *  linux/drivers/ide/pci/slc90e66.c    Version 0.11    September 11, 2002
+ *  linux/drivers/ide/pci/slc90e66.c    Version 0.12    May 12, 2006
  *
  *  Copyright (C) 2000-2002 Andre Hedrick <andre@linux-ide.org>
+ *  Copyright (C) 2006 MontaVista Software, Inc. <source@mvista.com>
  *
- * This a look-a-like variation of the ICH0 PIIX4 Ultra-66,
+ * This is a look-alike variation of the ICH0 PIIX4 Ultra-66,
  * but this keeps the ISA-Bridge and slots alive.
  *
  */
@@ -158,10 +159,8 @@ static int slc90e66_config_drive_for_dma (ide_drive_t *drive)
 {
         u8 speed = ide_dma_speed(drive, slc90e66_ratemask(drive));
 
-        if (!(speed)) {
-                u8 tspeed = ide_get_best_pio_mode(drive, 255, 5, NULL);
-                speed = slc90e66_dma_2_pio(XFER_PIO_0 + tspeed);
-        }
+        if (!speed)
+                return 0;
 
         (void) slc90e66_tune_chipset(drive, speed);
         return ide_dma_enable(drive);
@@ -176,16 +175,15 @@ static int slc90e66_config_drive_xfer_rate (ide_drive_t *drive)
 
         if (id && (id->capability & 1) && drive->autodma) {
 
-                if (ide_use_dma(drive)) {
-                        if (slc90e66_config_drive_for_dma(drive))
-                                return hwif->ide_dma_on(drive);
-                }
+                if (ide_use_dma(drive) && slc90e66_config_drive_for_dma(drive))
+                        return hwif->ide_dma_on(drive);
 
                 goto fast_ata_pio;
 
         } else if ((id->capability & 8) || (id->field_valid & 2)) {
 fast_ata_pio:
-                hwif->tuneproc(drive, 5);
+                (void) hwif->speedproc(drive, XFER_PIO_0 +
+                                       ide_get_best_pio_mode(drive, 255, 4, NULL));
                 return hwif->ide_dma_off_quietly(drive);
         }
         /* IORDY not supported */