From: Tejun Heo <htejun@gmail.com>
Date: Mon, 16 Jul 2007 05:29:40 +0000 (+0900)
Subject: libata: quickly trigger SATA SPD down after debouncing failed
X-Git-Tag: v2.6.23-rc1~219^2~5
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f1545154a5c96590b1992aac8ee1e2c445e301ed;p=linux-2.6

libata: quickly trigger SATA SPD down after debouncing failed

Debouncing failure is a good indicator of basic link problem.  Use
-EPIPE to indicate debouncing failure and make ata_eh_reset() invoke
sata_down_spd_limit() if the error occurs during reset.

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

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index c325b7a424..05922e9f4f 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -3267,9 +3267,11 @@ int sata_phy_debounce(struct ata_port *ap, const unsigned long *params,
 		last = cur;
 		last_jiffies = jiffies;
 
-		/* check deadline */
+		/* Check deadline.  If debouncing failed, return
+		 * -EPIPE to tell upper layer to lower link speed.
+		 */
 		if (time_after(jiffies, deadline))
-			return -EBUSY;
+			return -EPIPE;
 	}
 }
 
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 183eaf466d..1a4397ae9e 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -1790,7 +1790,7 @@ static int ata_eh_reset(struct ata_port *ap, int classify,
 			schedule_timeout_uninterruptible(delta);
 		}
 
-		if (reset == hardreset &&
+		if (rc == -EPIPE ||
 		    try == ARRAY_SIZE(ata_eh_reset_timeouts) - 1)
 			sata_down_spd_limit(ap);
 		if (hardreset)