diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 2d65b16..1041cb8 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -936,6 +936,8 @@
 		return NULL;
 
 	device_initialize(&master->dev);
+	master->bus_num = -1;
+	master->num_chipselect = 1;
 	master->dev.class = &spi_master_class;
 	master->dev.parent = get_device(dev);
 	spi_master_set_devdata(master, &master[1]);