cs5530/sc1200: add ->udma_filter methods
CS5530/SC1200 specifies that two drives on the same cable cannot mix
UDMA/MDMA. Add {cs5530,sc1200}_udma_filter() to handle this. This also
makes it possible to remove open-coded best DMA mode selection and use
standard ide_use_dma()/ide_max_dma_mode() helpers. While at it bump
version numbers.
There should be no functionality changes caused by this patch.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/pci/cs5530.c b/drivers/ide/pci/cs5530.c
index b2d7c13..8455001 100644
--- a/drivers/ide/pci/cs5530.c
+++ b/drivers/ide/pci/cs5530.c
@@ -1,10 +1,10 @@
/*
- * linux/drivers/ide/pci/cs5530.c Version 0.7 Sept 10, 2002
+ * linux/drivers/ide/pci/cs5530.c Version 0.71 Mar 10 2007
*
* Copyright (C) 2000 Andre Hedrick <andre@linux-ide.org>
- * Ditto of GNU General Public License.
- *
* Copyright (C) 2000 Mark Lord <mlord@pobox.com>
+ * Copyright (C) 2007 Bartlomiej Zolnierkiewicz
+ *
* May be copied or modified under the terms of the GNU General Public License
*
* Development of this chipset driver was funded
@@ -88,79 +88,66 @@
}
/**
- * cs5530_config_dma - select/set DMA and UDMA modes
+ * cs5530_udma_filter - UDMA filter
+ * @drive: drive
+ *
+ * cs5530_udma_filter() does UDMA mask filtering for the given drive
+ * taking into the consideration capabilities of the mate device.
+ *
+ * The CS5530 specifies that two drives sharing a cable cannot mix
+ * UDMA/MDMA. It has to be one or the other, for the pair, though
+ * different timings can still be chosen for each drive. We could
+ * set the appropriate timing bits on the fly, but that might be
+ * a bit confusing. So, for now we statically handle this requirement
+ * by looking at our mate drive to see what it is capable of, before
+ * choosing a mode for our own drive.
+ *
+ * Note: This relies on the fact we never fail from UDMA to MWDMA2
+ * but instead drop to PIO.
+ */
+
+static u8 cs5530_udma_filter(ide_drive_t *drive)
+{
+ ide_hwif_t *hwif = drive->hwif;
+ ide_drive_t *mate = &hwif->drives[(drive->dn & 1) ^ 1];
+ struct hd_driveid *mateid = mate->id;
+ u8 mask = hwif->ultra_mask;
+
+ if (mate->present == 0)
+ goto out;
+
+ if ((mateid->capability & 1) && __ide_dma_bad_drive(mate) == 0) {
+ if ((mateid->field_valid & 4) && (mateid->dma_ultra & 7))
+ goto out;
+ if ((mateid->field_valid & 2) && (mateid->dma_mword & 7))
+ mask = 0;
+ }
+out:
+ return mask;
+}
+
+/**
+ * cs5530_config_dma - set DMA/UDMA mode
* @drive: drive to tune
*
- * cs5530_config_dma() handles selection/setting of DMA/UDMA modes
- * for both the chipset and drive. The CS5530 has limitations about
- * mixing DMA/UDMA on the same cable.
+ * cs5530_config_dma() handles setting of DMA/UDMA mode
+ * for both the chipset and drive.
*/
-
-static int cs5530_config_dma (ide_drive_t *drive)
+
+static int cs5530_config_dma(ide_drive_t *drive)
{
- int udma_ok = 1, mode = 0;
- ide_hwif_t *hwif = HWIF(drive);
- int unit = drive->select.b.unit;
- ide_drive_t *mate = &hwif->drives[unit^1];
- struct hd_driveid *id = drive->id;
- unsigned int reg, timings = 0;
- unsigned long basereg;
+ ide_hwif_t *hwif = drive->hwif;
+ unsigned int reg, timings = 0;
+ unsigned long basereg;
+ u8 unit = drive->dn & 1, mode = 0;
/*
* Default to DMA-off in case we run into trouble here.
*/
hwif->dma_off_quietly(drive);
- /*
- * The CS5530 specifies that two drives sharing a cable cannot
- * mix UDMA/MDMA. It has to be one or the other, for the pair,
- * though different timings can still be chosen for each drive.
- * We could set the appropriate timing bits on the fly,
- * but that might be a bit confusing. So, for now we statically
- * handle this requirement by looking at our mate drive to see
- * what it is capable of, before choosing a mode for our own drive.
- *
- * Note: This relies on the fact we never fail from UDMA to MWDMA_2
- * but instead drop to PIO
- */
- if (mate->present) {
- struct hd_driveid *mateid = mate->id;
- if (mateid && (mateid->capability & 1) &&
- !__ide_dma_bad_drive(mate)) {
- if ((mateid->field_valid & 4) &&
- (mateid->dma_ultra & 7))
- udma_ok = 1;
- else if ((mateid->field_valid & 2) &&
- (mateid->dma_mword & 7))
- udma_ok = 0;
- else
- udma_ok = 1;
- }
- }
-
- /*
- * Now see what the current drive is capable of,
- * selecting UDMA only if the mate said it was ok.
- */
- if (id && (id->capability & 1) && drive->autodma &&
- !__ide_dma_bad_drive(drive)) {
- if (udma_ok && (id->field_valid & 4) && (id->dma_ultra & 7)) {
- if (id->dma_ultra & 4)
- mode = XFER_UDMA_2;
- else if (id->dma_ultra & 2)
- mode = XFER_UDMA_1;
- else if (id->dma_ultra & 1)
- mode = XFER_UDMA_0;
- }
- if (!mode && (id->field_valid & 2) && (id->dma_mword & 7)) {
- if (id->dma_mword & 4)
- mode = XFER_MW_DMA_2;
- else if (id->dma_mword & 2)
- mode = XFER_MW_DMA_1;
- else if (id->dma_mword & 1)
- mode = XFER_MW_DMA_0;
- }
- }
+ if (ide_use_dma(drive))
+ mode = ide_max_dma_mode(drive);
/*
* Tell the drive to switch to the new mode; abort on failure.
@@ -332,6 +319,7 @@
hwif->ultra_mask = 0x07;
hwif->mwdma_mask = 0x07;
+ hwif->udma_filter = cs5530_udma_filter;
hwif->ide_dma_check = &cs5530_config_dma;
if (!noautodma)
hwif->autodma = 1;