ide-4drives: manage I/O resources in driver

[linux-2.6] / drivers / ide / ide-dma.c

diff --git a/drivers/ide/ide-dma.c b/drivers/ide/ide-dma.c
index d0e7b537353e38ea1bb23ff6f0604f0d93777752..dc4bc06f98714b557c64730434311103cfd21bee 100644 (file)
--- a/drivers/ide/ide-dma.c
+++ b/drivers/ide/ide-dma.c
@@ -1,9 +1,13 @@
 /*
+ *  IDE DMA support (including IDE PCI BM-DMA).
+ *
  *  Copyright (C) 1995-1998   Mark Lord
  *  Copyright (C) 1999-2000   Andre Hedrick <andre@linux-ide.org>
  *  Copyright (C) 2004, 2007  Bartlomiej Zolnierkiewicz
  *
  *  May be copied or modified under the terms of the GNU General Public License
+ *
+ *  DMA is supported for all IDE devices (disk drives, cdroms, tapes, floppies).
  */
 
 /*
@@ -11,49 +15,6 @@
  */
 
 /*
- * This module provides support for the bus-master IDE DMA functions
- * of various PCI chipsets, including the Intel PIIX (i82371FB for
- * the 430 FX chipset), the PIIX3 (i82371SB for the 430 HX/VX and 
- * 440 chipsets), and the PIIX4 (i82371AB for the 430 TX chipset)
- * ("PIIX" stands for "PCI ISA IDE Xcellerator").
- *
- * Pretty much the same code works for other IDE PCI bus-mastering chipsets.
- *
- * DMA is supported for all IDE devices (disk drives, cdroms, tapes, floppies).
- *
- * By default, DMA support is prepared for use, but is currently enabled only
- * for drives which already have DMA enabled (UltraDMA or mode 2 multi/single),
- * or which are recognized as "good" (see table below).  Drives with only mode0
- * or mode1 (multi/single) DMA should also work with this chipset/driver
- * (eg. MC2112A) but are not enabled by default.
- *
- * Use "hdparm -i" to view modes supported by a given drive.
- *
- * The hdparm-3.5 (or later) utility can be used for manually enabling/disabling
- * DMA support, but must be (re-)compiled against this kernel version or later.
- *
- * To enable DMA, use "hdparm -d1 /dev/hd?" on a per-drive basis after booting.
- * If problems arise, ide.c will disable DMA operation after a few retries.
- * This error recovery mechanism works and has been extremely well exercised.
- *
- * IDE drives, depending on their vintage, may support several different modes
- * of DMA operation.  The boot-time modes are indicated with a "*" in
- * the "hdparm -i" listing, and can be changed with *knowledgeable* use of
- * the "hdparm -X" feature.  There is seldom a need to do this, as drives
- * normally power-up with their "best" PIO/DMA modes enabled.
- *
- * Testing has been done with a rather extensive number of drives,
- * with Quantum & Western Digital models generally outperforming the pack,
- * and Fujitsu & Conner (and some Seagate which are really Conner) drives
- * showing more lackluster throughput.
- *
- * Keep an eye on /var/adm/messages for "DMA disabled" messages.
- *
- * Some people have reported trouble with Intel Zappa motherboards.
- * This can be fixed by upgrading the AMI BIOS to version 1.00.04.BS0,
- * available from ftp://ftp.intel.com/pub/bios/10004bs0.exe
- * (thanks to Glen Morrell <glen@spin.Stanford.edu> for researching this).
- *
  * Thanks to "Christopher J. Reimer" <reimer@doe.carleton.ca> for
  * fixing the problem with the BIOS on some Acer motherboards.
  *
@@ -65,11 +26,6 @@
  *
  * Most importantly, thanks to Robert Bringman <rob@mars.trion.com>
  * for supplying a Promise UDMA board & WD UDMA drive for this work!
- *
- * And, yes, Intel Zappa boards really *do* use both PIIX IDE ports.
- *
- * ATA-66/100 and recovery functions, I forgot the rest......
- *
  */
 
 #include <linux/module.h>
@@ -618,6 +574,7 @@ static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base, u8 req_mode)
 {
        struct hd_driveid *id = drive->id;
        ide_hwif_t *hwif = drive->hwif;
+       const struct ide_port_ops *port_ops = hwif->port_ops;
        unsigned int mask = 0;
 
        switch(base) {
@@ -625,8 +582,8 @@ static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base, u8 req_mode)
                if ((id->field_valid & 4) == 0)
                        break;
 
-               if (hwif->udma_filter)
-                       mask = hwif->udma_filter(drive);
+               if (port_ops && port_ops->udma_filter)
+                       mask = port_ops->udma_filter(drive);
                else
                        mask = hwif->ultra_mask;
                mask &= id->dma_ultra;
@@ -642,8 +599,8 @@ static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base, u8 req_mode)
        case XFER_MW_DMA_0:
                if ((id->field_valid & 2) == 0)
                        break;
-               if (hwif->mdma_filter)
-                       mask = hwif->mdma_filter(drive);
+               if (port_ops && port_ops->mdma_filter)
+                       mask = port_ops->mdma_filter(drive);
                else
                        mask = hwif->mwdma_mask;
                mask &= id->dma_mword;
@@ -747,16 +704,7 @@ static int ide_tune_dma(ide_drive_t *drive)
 
        speed = ide_max_dma_mode(drive);
 
-       if (!speed) {
-                /* is this really correct/needed? */
-               if ((hwif->host_flags & IDE_HFLAG_CY82C693) &&
-                   ide_dma_good_drive(drive))
-                       return 1;
-               else
-                       return 0;
-       }
-
-       if (hwif->host_flags & IDE_HFLAG_NO_SET_MODE)
+       if (!speed)
                return 0;
 
        if (ide_set_dma_mode(drive, speed))