libata passthru: support PIO multi commands
support the pass through of PIO multi commands.
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index f70431a..8a66ca5 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -2551,10 +2551,6 @@
if (tf->protocol == ATA_PROT_DMA && dev->dma_mode == 0)
goto invalid_fld;
- if (cdb[1] & 0xe0)
- /* PIO multi not supported yet */
- goto invalid_fld;
-
/*
* 12 and 16 byte CDBs use different offsets to
* provide the various register values.
@@ -2606,6 +2602,22 @@
tf->device = qc->dev->devno ?
tf->device | ATA_DEV1 : tf->device & ~ATA_DEV1;
+ /* sanity check for pio multi commands */
+ if ((cdb[1] & 0xe0) && !is_multi_taskfile(tf))
+ goto invalid_fld;
+
+ if (is_multi_taskfile(tf)) {
+ unsigned int multi_count = 1 << (cdb[1] >> 5);
+
+ /* compare the passed through multi_count
+ * with the cached multi_count of libata
+ */
+ if (multi_count != dev->multi_count)
+ ata_dev_printk(dev, KERN_WARNING,
+ "invalid multi_count %u ignored\n",
+ multi_count);
+ }
+
/* READ/WRITE LONG use a non-standard sect_size */
qc->sect_size = ATA_SECT_SIZE;
switch (tf->command) {