IB/core: Export a common fw_ver sysfs entry

Now that all the devices have stopped exporting their own sysfs
entry points we can have the core export this on their behalf.

Eventually this may be removed but this provides for backwards
compatibility.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

drivers/infiniband/core/sysfs.c

@@ -38,6 +38,7 @@
 #include <linux/stat.h>
 #include <linux/string.h>
 #include <linux/netdevice.h>
+#include <linux/ethtool.h>
 
 #include <rdma/ib_mad.h>
 #include <rdma/ib_pma.h>
@@ -1196,16 +1197,28 @@ static ssize_t set_node_desc(struct device *device,
 	return count;
 }
 
+static ssize_t show_fw_ver(struct device *device, struct device_attribute *attr,
+			   char *buf)
+{
+	struct ib_device *dev = container_of(device, struct ib_device, dev);
+
+	ib_get_device_fw_str(dev, buf, PAGE_SIZE);
+	strlcat(buf, "\n", PAGE_SIZE);
+	return strlen(buf);
+}
+
 static DEVICE_ATTR(node_type, S_IRUGO, show_node_type, NULL);
 static DEVICE_ATTR(sys_image_guid, S_IRUGO, show_sys_image_guid, NULL);
 static DEVICE_ATTR(node_guid, S_IRUGO, show_node_guid, NULL);
 static DEVICE_ATTR(node_desc, S_IRUGO | S_IWUSR, show_node_desc, set_node_desc);
+static DEVICE_ATTR(fw_ver, S_IRUGO, show_fw_ver, NULL);
 
 static struct device_attribute *ib_class_attributes[] = {
 	&dev_attr_node_type,
 	&dev_attr_sys_image_guid,
 	&dev_attr_node_guid,
-	&dev_attr_node_desc
+	&dev_attr_node_desc,
+	&dev_attr_fw_ver,
 };
 
 static void free_port_list_attributes(struct ib_device *device)