libata,pata_via: revert ata_wait_idle() removal from ata_sff/via_tf_load()

Commit 978c0666 (libata: Remove excess delay in the tf_load path)
removed ata_wait_idle() from ata_sff_tf_load() and via_tf_load().
This caused obscure detection problems in sata_sil.

  https://bugzilla.kernel.org/show_bug.cgi?id=16606

The commit was pure performance optimization.  Revert it for now.

Reported-by: Dieter Plaetinck <dieter@plaetinck.be>
Reported-by: Jan Beulich <JBeulich@novell.com>
Bisected-by: gianluca <gianluca@sottospazio.it>
Cc: stable@kernel.org
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/ata/pata_via.c b/drivers/ata/pata_via.c
index 5e659885de16..ac8d7d97e408 100644
--- a/drivers/ata/pata_via.c
+++ b/drivers/ata/pata_via.c
@@ -417,6 +417,8 @@ static void via_tf_load(struct ata_port *ap, const struct ata_taskfile *tf)
                         tf->lbam,
                         tf->lbah);
         }
+
+        ata_wait_idle(ap);
 }
 
 static int via_port_start(struct ata_port *ap)