cs5535: PIO fixes

* Fix cs5535_tuneproc() to pass PIO transfer mode value instead of PIO mode
  number to cs5535_set_speed() (fixes random PIO timings being programmed
  and a possible OOPS).  Do a little cleanup while at it.

* Fix cs5535_set_speed() to check if the mate device is present (fixes PIO0
  taskfile timings being used if there is no other device on the cable).

* Use cs5535_tuneproc() in cs5535_dma_check().  The old code had the same
  issue as cs5535_tuneproc() and add additionally caused 0x00-0x04 transfer
  mode values (== default PIO, default PIO w/ IORDY + two invalid values)
  being set on the device instead of values 0x08-0x0c (XFER_PIO_[0,4]).

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

1 files changed, 17 insertions, 23 deletions

diff --git a/drivers/ide/pci/cs5535.c b/drivers/ide/pci/cs5535.c
index 9bd526db03cf..082ca7da2cbc 100644
--- a/drivers/ide/pci/cs5535.c
+++ b/drivers/ide/pci/cs5535.c
@@ -2,6 +2,7 @@
  * linux/drivers/ide/pci/cs5535.c
  *
  * Copyright (C) 2004-2005 Advanced Micro Devices, Inc.
+ * Copyright (C)      2007 Bartlomiej Zolnierkiewicz
  *
  * History:
  * 09/20/2005 - Jaya Kumar <jayakumar.ide@gmail.com>
@@ -83,14 +84,17 @@ static void cs5535_set_speed(ide_drive_t *drive, u8 speed)
 
         /* Set the PIO timings */
         if ((speed & XFER_MODE) == XFER_PIO) {
-                u8 pioa;
-                u8 piob;
-                u8 cmd;
+                ide_drive_t *pair = &drive->hwif->drives[drive->dn ^ 1];
+                u8 cmd, pioa;
 
-                pioa = speed - XFER_PIO_0;
-                piob = ide_get_best_pio_mode(&(drive->hwif->drives[!unit]),
-                                                255, 4);
-                cmd = pioa < piob ? pioa : piob;
+                cmd = pioa = speed - XFER_PIO_0;
+
+                if (pair->present) {
+                        u8 piob = ide_get_best_pio_mode(pair, 255, 4);
+
+                        if (piob < cmd)
+                                cmd = piob;
+                }
 
                 /* Write the speed of the current drive */
                 reg = (cs5535_pio_cmd_timings[cmd] << 16) |
@@ -151,32 +155,22 @@ static int cs5535_set_drive(ide_drive_t *drive, u8 speed)
  *
  *      A callback from the upper layers for PIO-only tuning.
  */
-static void cs5535_tuneproc(ide_drive_t *drive, u8 xferspeed)
+static void cs5535_tuneproc(ide_drive_t *drive, u8 pio)
 {
-        u8 modes[] = {  XFER_PIO_0, XFER_PIO_1, XFER_PIO_2, XFER_PIO_3,
-                        XFER_PIO_4 };
-
-        /* cs5535 max pio is pio 4, best_pio will check the blacklist.
-        i think we don't need to rate_filter the incoming xferspeed
-        since we know we're only going to choose pio */
-        xferspeed = ide_get_best_pio_mode(drive, xferspeed, 4);
-        ide_config_drive_speed(drive, modes[xferspeed]);
-        cs5535_set_speed(drive, xferspeed);
+        pio = ide_get_best_pio_mode(drive, pio, 4);
+        ide_config_drive_speed(drive, XFER_PIO_0 + pio);
+        cs5535_set_speed(drive, XFER_PIO_0 + pio);
 }
 
 static int cs5535_dma_check(ide_drive_t *drive)
 {
-        u8 speed;
-
         drive->init_speed = 0;
 
         if (ide_tune_dma(drive))
                 return 0;
 
-        if (ide_use_fast_pio(drive)) {
-                speed = ide_get_best_pio_mode(drive, 255, 4);
-                cs5535_set_drive(drive, speed);
-        }
+        if (ide_use_fast_pio(drive))
+                cs5535_tuneproc(drive, 255);
 
         return -1;
 }