diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c
index 357a2e0..258defd 100644
--- a/drivers/w1/w1_int.c
+++ b/drivers/w1/w1_int.c
@@ -100,7 +100,8 @@
 
         /* validate minimum functionality */
         if (!(master->touch_bit && master->reset_bus) &&
-            !(master->write_bit && master->read_bit)) {
+            !(master->write_bit && master->read_bit) &&
+	    !(master->write_byte && master->read_byte && master->reset_bus)) {
 		printk(KERN_ERR "w1_add_master_device: invalid function set\n");
 		return(-EINVAL);
         }