ses: add enclosure logical id

Export the NAA logical id for the enclosure.  This is optionally
available from the sas_transport_class, but it is really a property of
the enclosure.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jens Axboe <axboe@fb.com>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/misc/enclosure.c b/drivers/misc/enclosure.c
index e18278aa6bbb..958ee988a1e1 100644
--- a/drivers/misc/enclosure.c
+++ b/drivers/misc/enclosure.c
@@ -432,8 +432,21 @@ static ssize_t components_show(struct device *cdev,
 }
 static DEVICE_ATTR_RO(components);
 
+static ssize_t id_show(struct device *cdev,
+                                 struct device_attribute *attr,
+                                 char *buf)
+{
+        struct enclosure_device *edev = to_enclosure_device(cdev);
+
+        if (edev->cb->show_id)
+                return edev->cb->show_id(edev, buf);
+        return -EINVAL;
+}
+static DEVICE_ATTR_RO(id);
+
 static struct attribute *enclosure_class_attrs[] = {
         &dev_attr_components.attr,
+        &dev_attr_id.attr,
         NULL,
 };
 ATTRIBUTE_GROUPS(enclosure_class);