sata_nv: make hardreset return -EAGAIN on success

sata_nv hardreset can't classify but was left out while unifying
follow-up SRST request mechanism[1].  This caused detection failures
on those controllers.  Fix it.

Reported and bisected by Roland Dreier, Petr Vandrovec and Marc
Dionne.  Thanks guys.

[1] 305d2a1ab137d11d573319c315748a87060fe82d

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Roland Dreier <rdreier@cisco.com>
Cc: Petr Vandrovec <vandrove@vc.cvut.cz>
Cc: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

diff --git a/drivers/ata/sata_nv.c b/drivers/ata/sata_nv.c
index 109b074..858f706 100644 (file)
--- a/drivers/ata/sata_nv.c
+++ b/drivers/ata/sata_nv.c
@@ -1591,13 +1591,16 @@ static void nv_mcp55_thaw(struct ata_port *ap)
 static int nv_hardreset(struct ata_link *link, unsigned int *class,
                        unsigned long deadline)
 {
-       unsigned int dummy;
+       int rc;
 
        /* SATA hardreset fails to retrieve proper device signature on
-        * some controllers.  Don't classify on hardreset.  For more
-        * info, see http://bugzilla.kernel.org/show_bug.cgi?id=3352
+        * some controllers.  Request follow up SRST.  For more info,
+        * see http://bugzilla.kernel.org/show_bug.cgi?id=3352
         */
-       return sata_sff_hardreset(link, &dummy, deadline);
+       rc = sata_sff_hardreset(link, class, deadline);
+       if (rc)
+               return rc;
+       return -EAGAIN;
 }
 
 static void nv_adma_error_handler(struct ata_port *ap)