#define SAS_PORT_ATTRS         17
 #define SAS_RPORT_ATTRS                7
 #define SAS_END_DEV_ATTRS      3
+#define SAS_EXPANDER_ATTRS     7
 
 struct sas_internal {
        struct scsi_transport_template t;
        struct class_device_attribute private_phy_attrs[SAS_PORT_ATTRS];
        struct class_device_attribute private_rphy_attrs[SAS_RPORT_ATTRS];
        struct class_device_attribute private_end_dev_attrs[SAS_END_DEV_ATTRS];
+       struct class_device_attribute private_expander_attrs[SAS_EXPANDER_ATTRS];
 
        struct transport_container phy_attr_cont;
        struct transport_container rphy_attr_cont;
        struct transport_container end_dev_attr_cont;
+       struct transport_container expander_attr_cont;
 
        /*
         * The array of null terminated pointers to attributes
        struct class_device_attribute *phy_attrs[SAS_PORT_ATTRS + 1];
        struct class_device_attribute *rphy_attrs[SAS_RPORT_ATTRS + 1];
        struct class_device_attribute *end_dev_attrs[SAS_END_DEV_ATTRS + 1];
+       struct class_device_attribute *expander_attrs[SAS_EXPANDER_ATTRS + 1];
 };
 #define to_sas_internal(tmpl)  container_of(tmpl, struct sas_internal, t)
 
        struct list_head rphy_list;
        struct mutex lock;
        u32 next_target_id;
+       u32 next_expander_id;
 };
 #define to_sas_host_attrs(host)        ((struct sas_host_attrs *)(host)->shost_data)
 
        INIT_LIST_HEAD(&sas_host->rphy_list);
        mutex_init(&sas_host->lock);
        sas_host->next_target_id = 0;
+       sas_host->next_expander_id = 0;
        return 0;
 }
 
        device_initialize(&phy->dev);
        phy->dev.parent = get_device(parent);
        phy->dev.release = sas_phy_release;
-       sprintf(phy->dev.bus_id, "phy-%d:%d", shost->host_no, number);
+       if (scsi_is_sas_expander_device(parent)) {
+               struct sas_rphy *rphy = dev_to_rphy(parent);
+               sprintf(phy->dev.bus_id, "phy-%d-%d:%d", shost->host_no,
+                       rphy->scsi_target_id, number);
+       } else
+               sprintf(phy->dev.bus_id, "phy-%d:%d", shost->host_no, number);
 
        transport_setup_device(&phy->dev);
 
 }
 EXPORT_SYMBOL(sas_read_port_mode_page);
 
+static DECLARE_TRANSPORT_CLASS(sas_end_dev_class,
+                              "sas_end_device", NULL, NULL, NULL);
+
 #define sas_end_dev_show_simple(field, name, format_string, cast)      \
 static ssize_t                                                         \
 show_sas_end_dev_##name(struct class_device *cdev, char *buf)          \
 sas_end_dev_simple_attr(initiator_response_timeout, initiator_response_timeout,
                        "%d\n", int);
 
-static DECLARE_TRANSPORT_CLASS(sas_end_dev_class,
-                              "sas_end_device", NULL, NULL, NULL);
+static DECLARE_TRANSPORT_CLASS(sas_expander_class,
+                              "sas_expander", NULL, NULL, NULL);
+
+#define sas_expander_show_simple(field, name, format_string, cast)     \
+static ssize_t                                                         \
+show_sas_expander_##name(struct class_device *cdev, char *buf)         \
+{                                                                      \
+       struct sas_rphy *rphy = transport_class_to_rphy(cdev);          \
+       struct sas_expander_device *edev = rphy_to_expander_device(rphy); \
+                                                                       \
+       return snprintf(buf, 20, format_string, cast edev->field);      \
+}
+
+#define sas_expander_simple_attr(field, name, format_string, type)     \
+       sas_expander_show_simple(field, name, format_string, (type))    \
+static SAS_CLASS_DEVICE_ATTR(expander, name, S_IRUGO,                  \
+               show_sas_expander_##name, NULL)
+
+sas_expander_simple_attr(vendor_id, vendor_id, "%s\n", char *);
+sas_expander_simple_attr(product_id, product_id, "%s\n", char *);
+sas_expander_simple_attr(product_rev, product_rev, "%s\n", char *);
+sas_expander_simple_attr(component_vendor_id, component_vendor_id,
+                        "%s\n", char *);
+sas_expander_simple_attr(component_id, component_id, "%u\n", unsigned int);
+sas_expander_simple_attr(component_revision_id, component_revision_id, "%u\n",
+                        unsigned int);
+sas_expander_simple_attr(level, level, "%d\n", int);
 
 static DECLARE_TRANSPORT_CLASS(sas_rphy_class,
                "sas_rphy", NULL, NULL, NULL);
                rphy->contained;
 }
 
+static int sas_expander_match(struct attribute_container *cont,
+                             struct device *dev)
+{
+       struct Scsi_Host *shost;
+       struct sas_internal *i;
+       struct sas_rphy *rphy;
+
+       if (!scsi_is_sas_rphy(dev))
+               return 0;
+       shost = dev_to_shost(dev->parent->parent);
+       rphy = dev_to_rphy(dev);
+
+       if (!shost->transportt)
+               return 0;
+       if (shost->transportt->host_attrs.ac.class !=
+                       &sas_host_class.class)
+               return 0;
+
+       i = to_sas_internal(shost->transportt);
+       return &i->expander_attr_cont.ac == cont &&
+               (rphy->identify.device_type == SAS_EDGE_EXPANDER_DEVICE ||
+                rphy->identify.device_type == SAS_FANOUT_EXPANDER_DEVICE) &&
+               /* FIXME: remove contained eventually */
+               rphy->contained;
+}
+
 static void sas_rphy_release(struct device *dev)
 {
        struct sas_rphy *rphy = dev_to_rphy(dev);
 }
 EXPORT_SYMBOL(sas_end_device_alloc);
 
+/**
+ * sas_expander_alloc - allocate an rphy for an end device
+ *
+ * Allocates an SAS remote PHY structure, connected to @parent.
+ *
+ * Returns:
+ *     SAS PHY allocated or %NULL if the allocation failed.
+ */
+struct sas_rphy *sas_expander_alloc(struct sas_phy *parent,
+                                   enum sas_device_type type)
+{
+       struct Scsi_Host *shost = dev_to_shost(&parent->dev);
+       struct sas_expander_device *rdev;
+       struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);
+
+       BUG_ON(type != SAS_EDGE_EXPANDER_DEVICE &&
+              type != SAS_FANOUT_EXPANDER_DEVICE);
+
+       rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
+       if (!rdev) {
+               put_device(&parent->dev);
+               return NULL;
+       }
+
+       device_initialize(&rdev->rphy.dev);
+       rdev->rphy.dev.parent = get_device(&parent->dev);
+       rdev->rphy.dev.release = sas_rphy_release;
+       mutex_lock(&sas_host->lock);
+       rdev->rphy.scsi_target_id = sas_host->next_expander_id++;
+       mutex_unlock(&sas_host->lock);
+       sprintf(rdev->rphy.dev.bus_id, "expander-%d:%d",
+               shost->host_no, rdev->rphy.scsi_target_id);
+       rdev->rphy.identify.device_type = type;
+       /* FIXME: mark the rphy as being contained in a larger structure */
+       rdev->rphy.contained = 1;
+       transport_setup_device(&rdev->rphy.dev);
+
+       return &rdev->rphy;
+}
+EXPORT_SYMBOL(sas_expander_alloc);
 
 /**
  * sas_rphy_add  --  add a SAS remote PHY to the device hierachy
            (identify->target_port_protocols &
             (SAS_PROTOCOL_SSP|SAS_PROTOCOL_STP|SAS_PROTOCOL_SATA)))
                rphy->scsi_target_id = sas_host->next_target_id++;
-       else
-               rphy->scsi_target_id = -1;
        mutex_unlock(&sas_host->lock);
 
-       if (rphy->scsi_target_id != -1) {
+       if (identify->device_type == SAS_END_DEVICE &&
+           rphy->scsi_target_id != -1) {
                scsi_scan_target(&rphy->dev, parent->port_identifier,
                                rphy->scsi_target_id, ~0, 0);
        }
 #define SETUP_END_DEV_ATTRIBUTE(field)                                 \
        SETUP_TEMPLATE(end_dev_attrs, field, S_IRUGO, 1)
 
+#define SETUP_EXPANDER_ATTRIBUTE(field)                                        \
+       SETUP_TEMPLATE(expander_attrs, expander_##field, S_IRUGO, 1)
+
 /**
  * sas_attach_transport  --  instantiate SAS transport template
  * @ft:                SAS transport class function template
        i->end_dev_attr_cont.ac.match = sas_end_dev_match;
        transport_container_register(&i->end_dev_attr_cont);
 
+       i->expander_attr_cont.ac.class = &sas_expander_class.class;
+       i->expander_attr_cont.ac.attrs = &i->expander_attrs[0];
+       i->expander_attr_cont.ac.match = sas_expander_match;
+       transport_container_register(&i->expander_attr_cont);
+
        i->f = ft;
 
        count = 0;
        SETUP_END_DEV_ATTRIBUTE(end_dev_initiator_response_timeout);
        i->end_dev_attrs[count] = NULL;
 
+       count = 0;
+       SETUP_EXPANDER_ATTRIBUTE(vendor_id);
+       SETUP_EXPANDER_ATTRIBUTE(product_id);
+       SETUP_EXPANDER_ATTRIBUTE(product_rev);
+       SETUP_EXPANDER_ATTRIBUTE(component_vendor_id);
+       SETUP_EXPANDER_ATTRIBUTE(component_id);
+       SETUP_EXPANDER_ATTRIBUTE(component_revision_id);
+       SETUP_EXPANDER_ATTRIBUTE(level);
+       i->expander_attrs[count] = NULL;
+
        return &i->t;
 }
 EXPORT_SYMBOL(sas_attach_transport);
        transport_container_unregister(&i->phy_attr_cont);
        transport_container_unregister(&i->rphy_attr_cont);
        transport_container_unregister(&i->end_dev_attr_cont);
+       transport_container_unregister(&i->expander_attr_cont);
 
        kfree(i);
 }
        error = transport_class_register(&sas_end_dev_class);
        if (error)
                goto out_unregister_rphy;
+       error = transport_class_register(&sas_expander_class);
+       if (error)
+               goto out_unregister_end_dev;
 
        return 0;
 
+ out_unregister_end_dev:
+       transport_class_unregister(&sas_end_dev_class);
  out_unregister_rphy:
        transport_class_unregister(&sas_rphy_class);
  out_unregister_phy:
        transport_class_unregister(&sas_phy_class);
        transport_class_unregister(&sas_rphy_class);
        transport_class_unregister(&sas_end_dev_class);
+       transport_class_unregister(&sas_expander_class);
 }
 
 MODULE_AUTHOR("Christoph Hellwig");