2 files changed, 63 insertions, 13 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index c831c9efee60..aea766a48e05 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -5819,11 +5819,14 @@ static void ata_host_release(struct device *gendev, void *res)
         for (i = 0; i < host->n_ports; i++) {
                 struct ata_port *ap = host->ports[i];
 
-                if (ap && ap->ops->port_stop)
+                if (!ap)
+                        continue;
+
+                if ((host->flags & ATA_HOST_STARTED) && ap->ops->port_stop)
                         ap->ops->port_stop(ap);
         }
 
-        if (host->ops->host_stop)
+        if ((host->flags & ATA_HOST_STARTED) && host->ops->host_stop)
                 host->ops->host_stop(host);
 
         for (i = 0; i < host->n_ports; i++) {
@@ -5843,6 +5846,56 @@ static void ata_host_release(struct device *gendev, void *res)
 }
 
 /**
+ *      ata_host_start - start and freeze ports of an ATA host
+ *      @host: ATA host to start ports for
+ *
+ *      Start and then freeze ports of @host.  Started status is
+ *      recorded in host->flags, so this function can be called
+ *      multiple times.  Ports are guaranteed to get started only
+ *      once.
+ *
+ *      LOCKING:
+ *      Inherited from calling layer (may sleep).
+ *
+ *      RETURNS:
+ *      0 if all ports are started successfully, -errno otherwise.
+ */
+int ata_host_start(struct ata_host *host)
+{
+        int i, rc;
+
+        if (host->flags & ATA_HOST_STARTED)
+                return 0;
+
+        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) {
+                                ata_port_printk(ap, KERN_ERR, "failed to "
+                                                "start port (errno=%d)\n", rc);
+                                goto err_out;
+                        }
+                }
+
+                ata_eh_freeze_port(ap);
+        }
+
+        host->flags |= ATA_HOST_STARTED;
+        return 0;
+
+ err_out:
+        while (--i >= 0) {
+                struct ata_port *ap = host->ports[i];
+
+                if (ap->ops->port_stop)
+                        ap->ops->port_stop(ap);
+        }
+        return rc;
+}
+
+/**
  *      ata_sas_host_init - Initialize a host struct
  *      @host:  host to initialize
  *      @dev:   device host is attached to
@@ -5931,14 +5984,6 @@ int ata_device_add(const struct ata_probe_ent *ent)
                         continue;
                 }
 
-                /* start port */
-                rc = ap->ops->port_start(ap);
-                if (rc) {
-                        host->ports[i] = NULL;
-                        scsi_host_put(ap->scsi_host);
-                        goto err_out;
-                }
-
                 /* Report the secondary IRQ for second channel legacy */
                 if (i == 1 && ent->irq2)
                         irq_line = ent->irq2;
@@ -5956,11 +6001,13 @@ int ata_device_add(const struct ata_probe_ent *ent)
                                 ap->ioaddr.ctl_addr,
                                 ap->ioaddr.bmdma_addr,
                                 irq_line);
-
-                /* freeze port before requesting IRQ */
-                ata_eh_freeze_port(ap);
         }
 
+        /* start ports */
+        rc = ata_host_start(host);
+        if (rc)
+                goto err_out;
+
         /* obtain irq, that may be shared between channels */
         rc = devm_request_irq(dev, ent->irq, ent->port_ops->irq_handler,
                               ent->irq_flags, DRV_NAME, host);
@@ -6446,6 +6493,7 @@ EXPORT_SYMBOL_GPL(ata_dummy_port_ops);
 EXPORT_SYMBOL_GPL(ata_std_bios_param);
 EXPORT_SYMBOL_GPL(ata_std_ports);
 EXPORT_SYMBOL_GPL(ata_host_init);
+EXPORT_SYMBOL_GPL(ata_host_start);
 EXPORT_SYMBOL_GPL(ata_device_add);
 EXPORT_SYMBOL_GPL(ata_host_detach);
 EXPORT_SYMBOL_GPL(ata_sg_init);
diff --git a/include/linux/libata.h b/include/linux/libata.h
index ced9dd54035e..bda26e86f05f 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -210,6 +210,7 @@ enum {
 
         /* host set flags */
         ATA_HOST_SIMPLEX        = (1 << 0),     /* Host is simplex, one DMA channel per host only */
+        ATA_HOST_STARTED        = (1 << 1),     /* Host started */
 
         /* various lengths of time */
         ATA_TMOUT_BOOT          = 30 * HZ,      /* heuristic */
@@ -732,6 +733,7 @@ extern int ata_pci_device_resume(struct pci_dev *pdev);
 #endif
 extern int ata_pci_clear_simplex(struct pci_dev *pdev);
 #endif /* CONFIG_PCI */
+extern int ata_host_start(struct ata_host *host);
 extern int ata_device_add(const struct ata_probe_ent *ent);
 extern void ata_host_detach(struct ata_host *host);
 extern void ata_host_init(struct ata_host *, struct device *,