libata: move link onlineness check out of softreset methods

Currently, SATA softresets should do link onlineness check before
actually performing SRST protocol but it doesn't really belong to
softreset.

This patch moves onlineness check in softreset to ata_eh_reset() and
ata_eh_followup_srst_needed() to clean up code and help future sata_mv
changes which need clear separation between SCR and TF accesses.

sata_fsl is peculiar in that its softreset really isn't softreset but
combination of hardreset and softreset.  This patch adds dummy private
->prereset to keep the current behavior but the driver really should
implement separate hard and soft resets and return -EAGAIN from
hardreset if it should be follwed by softreset.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/ahci.c

@@ -1273,12 +1273,6 @@ static int ahci_softreset(struct ata_link *link, unsigned int *class,
 
 	DPRINTK("ENTER\n");
 
-	if (ata_link_offline(link)) {
-		DPRINTK("PHY reports no device\n");
-		*class = ATA_DEV_NONE;
-		return 0;
-	}
-
 	/* prepare for SRST (AHCI-1.1 10.4.1) */
 	rc = ahci_kick_engine(ap, 1);
 	if (rc && rc != -EOPNOTSUPP)

drivers/ata/libata-core.c

@@ -3541,6 +3541,10 @@ int ata_std_prereset(struct ata_link *link, unsigned long deadline)
 					"link for reset (errno=%d)\n", rc);
 	}
 
+	/* no point in trying softreset on offline link */
+	if (ata_link_offline(link))
+		ehc->i.action &= ~ATA_EH_SOFTRESET;
+
 	return 0;
 }
 

drivers/ata/libata-eh.c

@@ -2065,7 +2065,7 @@ static int ata_eh_followup_srst_needed(struct ata_link *link,
 				       int rc, int classify,
 				       const unsigned int *classes)
 {
-	if (link->flags & ATA_LFLAG_NO_SRST)
+	if ((link->flags & ATA_LFLAG_NO_SRST) || ata_link_offline(link))
 		return 0;
 	if (rc == -EAGAIN) {
 		if (classify)

drivers/ata/libata-sff.c

@@ -1889,11 +1889,6 @@ int ata_sff_softreset(struct ata_link *link, unsigned int *classes,
 
 	DPRINTK("ENTER\n");
 
-	if (ata_link_offline(link)) {
-		classes[0] = ATA_DEV_NONE;
-		goto out;
-	}
-
 	/* determine if device 0/1 are present */
 	if (ata_devchk(ap, 0))
 		devmask |= (1 << 0);
@@ -1919,7 +1914,6 @@ int ata_sff_softreset(struct ata_link *link, unsigned int *classes,
 		classes[1] = ata_sff_dev_classify(&link->device[1],
 						  devmask & (1 << 1), &err);
 
- out:
 	DPRINTK("EXIT, classes[0]=%u [1]=%u\n", classes[0], classes[1]);
 	return 0;
 }

drivers/ata/pata_bf54x.c

@@ -1103,11 +1103,6 @@ static int bfin_softreset(struct ata_link *link, unsigned int *classes,
 	unsigned int devmask = 0, err_mask;
 	u8 err;
 
-	if (ata_link_offline(link)) {
-		classes[0] = ATA_DEV_NONE;
-		goto out;
-	}
-
 	/* determine if device 0/1 are present */
 	if (bfin_devchk(ap, 0))
 		devmask |= (1 << 0);
@@ -1132,7 +1127,6 @@ static int bfin_softreset(struct ata_link *link, unsigned int *classes,
 		classes[1] = ata_sff_dev_classify(&ap->link.device[1],
 					devmask & (1 << 1), &err);
 
- out:
 	return 0;
 }
 

drivers/ata/pata_scc.c

@@ -615,11 +615,6 @@ static int scc_softreset(struct ata_link *link, unsigned int *classes,
 
 	DPRINTK("ENTER\n");
 
-	if (ata_link_offline(link)) {
-		classes[0] = ATA_DEV_NONE;
-		goto out;
-	}
-
 	/* determine if device 0/1 are present */
 	if (scc_devchk(ap, 0))
 		devmask |= (1 << 0);
@@ -645,7 +640,6 @@ static int scc_softreset(struct ata_link *link, unsigned int *classes,
 		classes[1] = ata_sff_dev_classify(&ap->link.device[1],
 						  devmask & (1 << 1), &err);
 
- out:
 	DPRINTK("EXIT, classes[0]=%u [1]=%u\n", classes[0], classes[1]);
 	return 0;
 }

drivers/ata/sata_fsl.c

@@ -678,6 +678,15 @@ static unsigned int sata_fsl_dev_classify(struct ata_port *ap)
 	return ata_dev_classify(&tf);
 }
 
+static int sata_fsl_prereset(struct ata_linke *link, unsigned long deadline)
+{
+	/* FIXME: Never skip softreset, sata_fsl_softreset() is
+	 * combination of soft and hard resets.  sata_fsl_softreset()
+	 * needs to be splitted into soft and hard resets.
+	 */
+	return 0;
+}
+
 static int sata_fsl_softreset(struct ata_link *link, unsigned int *class,
 			      unsigned long deadline)
 {
@@ -1157,6 +1166,7 @@ static const struct ata_port_operations sata_fsl_ops = {
 
 	.freeze = sata_fsl_freeze,
 	.thaw = sata_fsl_thaw,
+	.prereset = sata_fsl_prereset,
 	.softreset = sata_fsl_softreset,
 	.post_internal_cmd = sata_fsl_post_internal_cmd,
 

drivers/ata/sata_sil24.c

@@ -663,12 +663,6 @@ static int sil24_softreset(struct ata_link *link, unsigned int *class,
 
 	DPRINTK("ENTER\n");
 
-	if (ata_link_offline(link)) {
-		DPRINTK("PHY reports no device\n");
-		*class = ATA_DEV_NONE;
-		goto out;
-	}
-
 	/* put the port into known state */
 	if (sil24_init_port(ap)) {
 		reason = "port not ready";
@@ -693,7 +687,6 @@ static int sil24_softreset(struct ata_link *link, unsigned int *class,
 	sil24_read_tf(ap, 0, &tf);
 	*class = ata_dev_classify(&tf);
 
- out:
 	DPRINTK("EXIT, class=%u\n", *class);
 	return 0;