Add optional dynamic assignment of tracing devices major nr

Setting FT_TASK_TRACE_MAJOR, LOG_MAJOR, FT_TRACE_MAJOR to 0
allows to have them automatically assigned by the kernel

1 files changed, 9 insertions, 2 deletions

diff --git a/litmus/ftdev.c b/litmus/ftdev.c
index 1c1c241a0a69..8b2d74d816a2 100644
--- a/litmus/ftdev.c
+++ b/litmus/ftdev.c
@@ -332,8 +332,15 @@ int register_ftdev(struct ftdev* ftdev, const char* name, int major)
         dev_t   trace_dev;
         int error = 0;
 
-        trace_dev = MKDEV(major, 0);
-        error     = register_chrdev_region(trace_dev, ftdev->minor_cnt, name);
+        if(major) {
+                trace_dev = MKDEV(major, 0);
+                error = register_chrdev_region(trace_dev, ftdev->minor_cnt,
+                                               name);
+        } else {
+                error = alloc_chrdev_region(&trace_dev, 0, ftdev->minor_cnt,
+                                name);
+                major = MAJOR(trace_dev);
+        }
         if (error)
         {
                 printk(KERN_WARNING "ftdev(%s): "