diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index df2e05738f3b..ea53e6a570b4 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -2305,8 +2305,8 @@ static void atapi_request_sense(struct ata_queued_cmd *qc) qc->tf.feature |= ATAPI_PKT_DMA; } else { qc->tf.protocol = ATA_PROT_ATAPI; - qc->tf.lbam = (8 * 1024) & 0xff; - qc->tf.lbah = (8 * 1024) >> 8; + qc->tf.lbam = SCSI_SENSE_BUFFERSIZE; + qc->tf.lbah = 0; } qc->nbytes = SCSI_SENSE_BUFFERSIZE; @@ -2415,6 +2415,7 @@ static unsigned int atapi_xlat(struct ata_queued_cmd *qc) struct ata_device *dev = qc->dev; int using_pio = (dev->flags & ATA_DFLAG_PIO); int nodata = (scmd->sc_data_direction == DMA_NONE); + unsigned int nbytes; memset(qc->cdb, 0, dev->cdb_len); memcpy(qc->cdb, scmd->cmnd, scmd->cmd_len); @@ -2434,14 +2435,20 @@ static unsigned int atapi_xlat(struct ata_queued_cmd *qc) if (!using_pio && ata_check_atapi_dma(qc)) using_pio = 1; + /* Some controller variants snoop this value for Packet transfers + to do state machine and FIFO management. Thus we want to set it + properly, and for DMA where it is effectively meaningless */ + nbytes = min(qc->nbytes, (unsigned int)63 * 1024); + + qc->tf.lbam = (nbytes & 0xFF); + qc->tf.lbah = (nbytes >> 8); + if (using_pio || nodata) { /* no data, or PIO data xfer */ if (nodata) qc->tf.protocol = ATA_PROT_ATAPI_NODATA; else qc->tf.protocol = ATA_PROT_ATAPI; - qc->tf.lbam = (8 * 1024) & 0xff; - qc->tf.lbah = (8 * 1024) >> 8; } else { /* DMA data xfer */ qc->tf.protocol = ATA_PROT_ATAPI_DMA; @@ -2452,6 +2459,9 @@ static unsigned int atapi_xlat(struct ata_queued_cmd *qc) qc->tf.feature |= ATAPI_DMADIR; } + + /* FIXME: We need to translate 0x05 READ_BLOCK_LIMITS to a MODE_SENSE + as ATAPI tape drives don't get this right otherwise */ return 0; }