1 files changed, 60 insertions, 18 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index ec3ce120a517..81898036dbca 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -3373,14 +3373,20 @@ void ata_wait_after_reset(struct ata_port *ap, unsigned long deadline)
 	 * to clear 0xff after reset.  For example, HHD424020F7SV00
 	 * iVDR needs >= 800ms while.  Quantum GoVault needs even more
 	 * than that.
+	 *
+	 * Note that some PATA controllers (pata_ali) explode if
+	 * status register is read more than once when there's no
+	 * device attached.
 	 */
-	while (1) {
-		u8 status = ata_chk_status(ap);
+	if (ap->flags & ATA_FLAG_SATA) {
+		while (1) {
+			u8 status = ata_chk_status(ap);
 
-		if (status != 0xff || time_after(jiffies, deadline))
-			return;
+			if (status != 0xff || time_after(jiffies, deadline))
+				return;
 
-		msleep(50);
+			msleep(50);
+		}
 	}
 }
 
@@ -6821,19 +6827,6 @@ static void ata_host_release(struct device *gendev, void *res)
 		if (!ap)
 			continue;
 
-		if ((host->flags & ATA_HOST_STARTED) && ap->ops->port_stop)
-			ap->ops->port_stop(ap);
-	}
-
-	if ((host->flags & ATA_HOST_STARTED) && host->ops->host_stop)
-		host->ops->host_stop(host);
-
-	for (i = 0; i < host->n_ports; i++) {
-		struct ata_port *ap = host->ports[i];
-
-		if (!ap)
-			continue;
-
 		if (ap->scsi_host)
 			scsi_host_put(ap->scsi_host);
 
@@ -6960,6 +6953,24 @@ struct ata_host *ata_host_alloc_pinfo(struct device *dev,
 	return host;
 }
 
+static void ata_host_stop(struct device *gendev, void *res)
+{
+	struct ata_host *host = dev_get_drvdata(gendev);
+	int i;
+
+	WARN_ON(!(host->flags & ATA_HOST_STARTED));
+
+	for (i = 0; i < host->n_ports; i++) {
+		struct ata_port *ap = host->ports[i];
+
+		if (ap->ops->port_stop)
+			ap->ops->port_stop(ap);
+	}
+
+	if (host->ops->host_stop)
+		host->ops->host_stop(host);
+}
+
 /**
  *	ata_host_start - start and freeze ports of an ATA host
  *	@host: ATA host to start ports for
@@ -6978,6 +6989,8 @@ struct ata_host *ata_host_alloc_pinfo(struct device *dev,
  */
 int ata_host_start(struct ata_host *host)
 {
+	int have_stop = 0;
+	void *start_dr = NULL;
 	int i, rc;
 
 	if (host->flags & ATA_HOST_STARTED)
@@ -6989,6 +7002,22 @@ int ata_host_start(struct ata_host *host)
 		if (!host->ops && !ata_port_is_dummy(ap))
 			host->ops = ap->ops;
 
+		if (ap->ops->port_stop)
+			have_stop = 1;
+	}
+
+	if (host->ops->host_stop)
+		have_stop = 1;
+
+	if (have_stop) {
+		start_dr = devres_alloc(ata_host_stop, 0, GFP_KERNEL);
+		if (!start_dr)
+			return -ENOMEM;
+	}
+
+	for (i = 0; i < host->n_ports; i++) {
+		struct ata_port *ap = host->ports[i];
+
 		if (ap->ops->port_start) {
 			rc = ap->ops->port_start(ap);
 			if (rc) {
@@ -7001,6 +7030,8 @@ int ata_host_start(struct ata_host *host)
 		ata_eh_freeze_port(ap);
 	}
 
+	if (start_dr)
+		devres_add(host->dev, start_dr);
 	host->flags |= ATA_HOST_STARTED;
 	return 0;
 
@@ -7011,6 +7042,7 @@ int ata_host_start(struct ata_host *host)
 		if (ap->ops->port_stop)
 			ap->ops->port_stop(ap);
 	}
+	devres_free(start_dr);
 	return rc;
 }
 
@@ -7178,6 +7210,10 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
  *	request IRQ and register it.  This helper takes necessasry
  *	arguments and performs the three steps in one go.
  *
+ *	An invalid IRQ skips the IRQ registration and expects the host to
+ *	have set polling mode on the port. In this case, @irq_handler
+ *	should be NULL.
+ *
  *	LOCKING:
  *	Inherited from calling layer (may sleep).
  *
@@ -7194,6 +7230,12 @@ int ata_host_activate(struct ata_host *host, int irq,
 	if (rc)
 		return rc;
 
+	/* Special case for polling mode */
+	if (!irq) {
+		WARN_ON(irq_handler);
+		return ata_host_register(host, sht);
+	}
+
 	rc = devm_request_irq(host->dev, irq, irq_handler, irq_flags,
 			      dev_driver_string(host->dev), host);
 	if (rc)