diff options
| author | Jeff Garzik <jgarzik@redhat.com> | 2004-05-16 10:35:15 -0400 |
|---|---|---|
| committer | Jeff Garzik <jgarzik@redhat.com> | 2004-05-16 10:35:15 -0400 |
| commit | d89ee0218780580d748a7d43344c87bb1153886a (patch) | |
| tree | 481331d02e4abad6722d882711397d030689f396 | |
| parent | 80e00375262ea73f746262e39f5ea41bdfe0ede5 (diff) | |
[libata] DMADIR support
DMADIR bit is necessary for some PATA->SATA bridges. These
bridges require the OS driver to specify the data xfer direction,
for PACKET (a.k.a. scsi) commands.
A reliable DMADIR detection method hasn't yet been developed,
and ATAPI is still a WIP, so DMADIR is enabled with an ifdef for
now.
| -rw-r--r-- | drivers/scsi/libata-scsi.c | 6 | ||||
| -rw-r--r-- | include/linux/ata.h | 2 | ||||
| -rw-r--r-- | include/linux/libata.h | 1 |
3 files changed, 9 insertions, 0 deletions
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c index ab308576b2e6..5d06d5d391b2 100644 --- a/drivers/scsi/libata-scsi.c +++ b/drivers/scsi/libata-scsi.c @@ -927,6 +927,12 @@ static unsigned int atapi_xlat(struct ata_queued_cmd *qc, u8 *scsicmd) qc->flags |= ATA_QCFLAG_SG; /* data is present; dma-map it */ qc->tf.protocol = ATA_PROT_ATAPI_DMA; qc->tf.feature |= ATAPI_PKT_DMA; + +#ifdef ATAPI_ENABLE_DMADIR + /* some SATA bridges need us to indicate data xfer direction */ + if (cmd->sc_data_direction != SCSI_DATA_WRITE) + qc->tf.feature |= ATAPI_DMADIR; +#endif } return 0; diff --git a/include/linux/ata.h b/include/linux/ata.h index 7275d89ace21..053fd4b64da6 100644 --- a/include/linux/ata.h +++ b/include/linux/ata.h @@ -134,6 +134,8 @@ enum { /* ATAPI stuff */ ATAPI_PKT_DMA = (1 << 0), + ATAPI_DMADIR = (1 << 2), /* ATAPI data dir: + 0=to device, 1=to host */ /* cable types */ ATA_CBL_NONE = 0, diff --git a/include/linux/libata.h b/include/linux/libata.h index c2172feb0d37..077f6461ab2a 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -40,6 +40,7 @@ #undef ATA_ENABLE_ATAPI /* define to enable ATAPI support */ #undef ATA_ENABLE_PATA /* define to enable PATA support in some * low-level drivers */ +#undef ATAPI_ENABLE_DMADIR /* enables ATAPI DMADIR bridge support */ /* note: prints function name for you */ |