int __ide_dma_on (ide_drive_t *drive)
{
- /* consult the list of known "bad" drives */
- if (__ide_dma_bad_drive(drive))
- return 1;
-
drive->using_dma = 1;
ide_toggle_bounce(drive, 1);
ide_hwif_t *hwif = drive->hwif;
int rc;
- rc = ide_dma_check(drive);
+ /*
+ * Force DMAing for the beginning of the check.
+ * Some chipsets appear to do interesting
+ * things, if not checked and cleared.
+ * PARANOIA!!!
+ */
+ hwif->dma_off_quietly(drive);
- switch(rc) {
- case -1: /* DMA needs to be disabled */
- hwif->dma_off_quietly(drive);
- return -1;
- case 0: /* DMA needs to be enabled */
- return hwif->ide_dma_on(drive);
- case 1: /* DMA setting cannot be changed */
- break;
- default:
- BUG();
- break;
- }
+ rc = ide_dma_check(drive);
+ if (rc)
+ return rc;
- return rc;
+ return hwif->ide_dma_on(drive);
}
#ifdef CONFIG_BLK_DEV_IDEDMA_PCI
hwif->dma_base = base;
- if (hwif->mate)
- hwif->dma_master = hwif->channel ? hwif->mate->dma_base : base;
- else
- hwif->dma_master = base;
-
if (!(hwif->dma_command))
hwif->dma_command = hwif->dma_base;
if (!(hwif->dma_vendor1))
hwif->drives[1].name, (dma_stat & 0x40) ? "DMA" : "pio");
}
printk("\n");
-
- BUG_ON(!hwif->dma_master);
}
EXPORT_SYMBOL_GPL(ide_setup_dma);