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>
diff --git a/drivers/ata/pata_scc.c b/drivers/ata/pata_scc.c
index 2d048ef..aab068f 100644
--- a/drivers/ata/pata_scc.c
+++ b/drivers/ata/pata_scc.c
@@ -785,7 +785,7 @@
static void scc_data_xfer (struct ata_device *adev, unsigned char *buf,
unsigned int buflen, int write_data)
{
- struct ata_port *ap = adev->ap;
+ struct ata_port *ap = adev->link->ap;
unsigned int words = buflen >> 1;
unsigned int i;
u16 *buf16 = (u16 *) buf;