libata: Add atapi_dmadir force flag

Some device require DMADIR to be enabled, but are not detected as such
by atapi_id_dmadir.  One such example is "Asus Serillel 2"
SATA-host-to-PATA-device bridge: the bridge itself requires DMADIR,
even if the bridged device does not.

As atapi_dmadir module parameter can cause problems with some devices
(as per Tejun Heo's memory), enabling it globally may not be possible
depending on the hardware.

This patch adds atapi_dmadir in the form of a "force" horkage value,
allowing global, per-bus and per-device control.

Signed-off-by: Vincent Pelletier <plr.vincent@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/libata.h b/include/linux/libata.h
index 47e029236f6e..c886dc87aa81 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -399,6 +399,7 @@ enum {
         ATA_HORKAGE_BROKEN_FPDMA_AA     = (1 << 15),    /* skip AA */
         ATA_HORKAGE_DUMP_ID     = (1 << 16),    /* dump IDENTIFY data */
         ATA_HORKAGE_MAX_SEC_LBA48 = (1 << 17),  /* Set max sects to 65535 */
+        ATA_HORKAGE_ATAPI_DMADIR = (1 << 18),   /* device requires dmadir */
 
          /* DMA mask for user DMA control: User visible values; DO NOT
             renumber */