pata_pdc202xx_old: Fix crashes with ATAPI

The PDC202xx older devices do not support ATAPI DMA via the usual
interfaces. What documentation I have isn't sufficient to support DMA and
it isn't clear if the Windows drivers do this or it is possible at all.
(Neither do the drivers/ide old drivers)

So turn it ATAPI DMA off, these are disk optimised controllers.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 19 insertions, 0 deletions

diff --git a/drivers/ata/pata_pdc202xx_old.c b/drivers/ata/pata_pdc202xx_old.c
index 8f2815601791..6c9689b59b06 100644
--- a/drivers/ata/pata_pdc202xx_old.c
+++ b/drivers/ata/pata_pdc202xx_old.c
@@ -244,6 +244,24 @@ static int pdc2026x_port_start(struct ata_port *ap)
         return ata_sff_port_start(ap);
 }
 
+/**
+ *      pdc2026x_check_atapi_dma - Check whether ATAPI DMA can be supported for this command
+ *      @qc: Metadata associated with taskfile to check
+ *
+ *      Just say no - not supported on older Promise.
+ *
+ *      LOCKING:
+ *      None (inherited from caller).
+ *
+ *      RETURNS: 0 when ATAPI DMA can be used
+ *               1 otherwise
+ */
+
+static int pdc2026x_check_atapi_dma(struct ata_queued_cmd *qc)
+{
+        return 1;
+}
+
 static struct scsi_host_template pdc202xx_sht = {
         .module                 = THIS_MODULE,
         .name                   = DRV_NAME,
@@ -311,6 +329,7 @@ static struct ata_port_operations pdc2026x_port_ops = {
         .post_internal_cmd = ata_bmdma_post_internal_cmd,
         .cable_detect   = pdc2026x_cable_detect,
 
+        .check_atapi_dma= pdc2026x_check_atapi_dma,
         .bmdma_setup    = ata_bmdma_setup,
         .bmdma_start    = pdc2026x_bmdma_start,
         .bmdma_stop     = pdc2026x_bmdma_stop,