IB/core: Add get FW version string to the core

Allow for a common core function to get firmware version strings
from the individual devices.

In later patches this format can then then be used to pass a
properly formated version string through the IPoIB layer.

The problem with the current code in the IPoIB layer is that it is
specific to certain hardware types.

Furthermore, this gives us a common function through which the core
can provide a common sysfs entry.  Eventually we may want to
remove the sysfs export but this provides for user space backwards
compatibility.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/core/device.c

@@ -311,6 +311,15 @@ static int read_port_immutable(struct ib_device *device)
 	return 0;
 }
 
+void ib_get_device_fw_str(struct ib_device *dev, char *str, size_t str_len)
+{
+	if (dev->get_dev_fw_str)
+		dev->get_dev_fw_str(dev, str, str_len);
+	else
+		str[0] = '\0';
+}
+EXPORT_SYMBOL(ib_get_device_fw_str);
+
 /**
  * ib_register_device - Register an IB device with IB core
  * @device:Device to register

include/rdma/ib_verbs.h

@@ -1956,6 +1956,7 @@ struct ib_device {
 	 * in fast paths.
 	 */
 	int (*get_port_immutable)(struct ib_device *, u8, struct ib_port_immutable *);
+	void (*get_dev_fw_str)(struct ib_device *, char *str, size_t str_len);
 };
 
 struct ib_client {
@@ -1991,6 +1992,8 @@ struct ib_client {
 struct ib_device *ib_alloc_device(size_t size);
 void ib_dealloc_device(struct ib_device *device);
 
+void ib_get_device_fw_str(struct ib_device *device, char *str, size_t str_len);
+
 int ib_register_device(struct ib_device *device,
 		       int (*port_callback)(struct ib_device *,
 					    u8, struct kobject *));