ide: add ide_set{_max}_pio() (take 4)

* Add IDE_HFLAG_ABUSE_{PREFETCH,FAST_DEVSEL,DMA_MODES} flags
  and set them in ht6560, cmd640, cmd64x and sc1200 host drivers.

* Add set_pio_mode_abuse() for checking if host driver has a non-standard
  ->tuneproc() implementation and use it in do_special().

* Add ide_set_pio() for setting PIO mode (it uses hwif->pio_mask to find
  the maximum PIO mode supported by the host), also add ide_set_max_pio()
  wrapper for ide_set_pio() to use for auto-tuning.  Convert users of
  ->tuneproc to use ide_set{_max}_pio() where possible.  This leaves only
  do_special(), set_using_pio(), ide_hwif_restore() and ide_set_pio() as
  a direct users of ->tuneproc.

* Remove no longer needed ide_get_best_pio_mode() calls and printk-s
  reporting PIO mode selected from ->tuneproc implementations.

* Rename ->tuneproc hook to ->set_pio_mode and make 'pio' argument const.

* Remove stale comment from ide_config_drive_speed().

v2:
* Fix "ata_" prefix (Noticed by Jeff).

v3:
* Minor cleanups/fixups per Sergei's suggestions.

v4:
* Fix compile problem in drivers/ide/pci/cmd640.c
  (Noticed by Andrew Morton).

* Improve some ->set_pio_mode comments.

Reviewed-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/drivers/ide/ide-lib.c b/drivers/ide/ide-lib.c
index 957618849540..8400b1b4aa1b 100644
--- a/drivers/ide/ide-lib.c
+++ b/drivers/ide/ide-lib.c
@@ -325,6 +325,35 @@ u8 ide_get_best_pio_mode (ide_drive_t *drive, u8 mode_wanted, u8 max_mode)
 
 EXPORT_SYMBOL_GPL(ide_get_best_pio_mode);
 
+/* req_pio == "255" for auto-tune */
+void ide_set_pio(ide_drive_t *drive, u8 req_pio)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        u8 host_pio, pio;
+
+        if (hwif->set_pio_mode == NULL)
+                return;
+
+        BUG_ON(hwif->pio_mask == 0x00);
+
+        host_pio = fls(hwif->pio_mask) - 1;
+
+        pio = ide_get_best_pio_mode(drive, req_pio, host_pio);
+
+        /*
+         * TODO:
+         * - report device max PIO mode
+         * - check req_pio != 255 against device max PIO mode
+         */
+        printk(KERN_DEBUG "%s: host max PIO%d wanted PIO%d%s selected PIO%d\n",
+                          drive->name, host_pio, req_pio,
+                          req_pio == 255 ? "(auto-tune)" : "", pio);
+
+        hwif->set_pio_mode(drive, pio);
+}
+
+EXPORT_SYMBOL_GPL(ide_set_pio);
+
 /**
  *      ide_toggle_bounce       -       handle bounce buffering
  *      @drive: drive to update