[update] check whether it's a same console device.
@@ -1116,7 +1116,7 @@ RTM_EXPORT(rt_console_get_device);
*
* @param name the name of new console device
*
- * @return the old console device handler
+ * @return the old console device handler on successful, or RT_NULL on failure.
*/
rt_device_t rt_console_set_device(const char *name)
{
@@ -1127,6 +1127,10 @@ rt_device_t rt_console_set_device(const char *name)
/* find new console device */
new_device = rt_device_find(name);
+
+ /* check whether it's a same device */
+ if (new_device == old_device) return RT_NULL;
+
if (new_device != RT_NULL)
{
if (_console_device != RT_NULL)
