libata-link: introduce ata_link

Introduce ata_link.  It abstracts PHY and sits between ata_port and
ata_device.  This new level of abstraction is necessary to support
SATA Port Multiplier, which basically adds a bunch of links (PHYs) to
a ATA host port.  Fields related to command execution, spd_limit and
EH are per-link and thus moved to ata_link.

This patch only defines the host link.  Multiple link handling will be
added later.  Also, a lot of ap->link derefences are added but many of
them will be removed as each part is converted to deal directly with
ata_link instead of ata_port.

This patch introduces no behavior change.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/ata/pata_it821x.c b/drivers/ata/pata_it821x.c
index 5d8b91e70ecd..ece1a28f0a4a 100644
--- a/drivers/ata/pata_it821x.c
+++ b/drivers/ata/pata_it821x.c
@@ -391,7 +391,7 @@ static void it821x_passthru_dev_select(struct ata_port *ap,
 {
         struct it821x_dev *itdev = ap->private_data;
         if (itdev && device != itdev->last_device) {
-                struct ata_device *adev = &ap->device[device];
+                struct ata_device *adev = &ap->link.device[device];
                 it821x_program(ap, adev, itdev->pio[adev->devno]);
                 itdev->last_device = device;
         }
@@ -464,7 +464,7 @@ static int it821x_smart_set_mode(struct ata_port *ap, struct ata_device **unused
         int i;
 
         for (i = 0; i < ATA_MAX_DEVICES; i++) {
-                struct ata_device *dev = &ap->device[i];
+                struct ata_device *dev = &ap->link.device[i];
                 if (ata_dev_enabled(dev)) {
                         /* We don't really care */
                         dev->pio_mode = XFER_PIO_0;