libata: IORDY handling
I believe this version meets all Sergei's objections
Correct the logic for when we issue a set features for transfer mode
- If the device has IORDY and the controller has IORDY - set the mode
- If the device has IORDY and the controller does not - turn IORDY off
- If neither has IORDY do nothing
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 9b7f3c4..3dd0e94 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4373,7 +4373,14 @@
tf.feature = SETFEATURES_XFER;
tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_POLLING;
tf.protocol = ATA_PROT_NODATA;
- tf.nsect = dev->xfer_mode;
+ /* If we are using IORDY we must send the mode setting command */
+ if (ata_pio_need_iordy(dev))
+ tf.nsect = dev->xfer_mode;
+ /* If the device has IORDY and the controller does not - turn it off */
+ else if (ata_id_has_iordy(dev->id))
+ tf.nsect = 0x01;
+ else /* In the ancient relic department - skip all of this */
+ return 0;
err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);