1 files changed, 7 insertions, 1 deletions

diff --git a/drivers/tty/hvc/hvc_udbg.c b/drivers/tty/hvc/hvc_udbg.c
index 4c9b13e7748c..72228276fe31 100644
--- a/drivers/tty/hvc/hvc_udbg.c
+++ b/drivers/tty/hvc/hvc_udbg.c
@@ -36,7 +36,7 @@ static int hvc_udbg_put(uint32_t vtermno, const char *buf, int count)
 {
         int i;
 
-        for (i = 0; i < count; i++)
+        for (i = 0; i < count && udbg_putc; i++)
                 udbg_putc(buf[i]);
 
         return i;
@@ -67,6 +67,9 @@ static int __init hvc_udbg_init(void)
 {
         struct hvc_struct *hp;
 
+        if (!udbg_putc)
+                return -ENODEV;
+
         BUG_ON(hvc_udbg_dev);
 
         hp = hvc_alloc(0, 0, &hvc_udbg_ops, 16);
@@ -88,6 +91,9 @@ module_exit(hvc_udbg_exit);
 
 static int __init hvc_udbg_console_init(void)
 {
+        if (!udbg_putc)
+                return -ENODEV;
+
         hvc_instantiate(0, 0, &hvc_udbg_ops);
         add_preferred_console("hvc", 0, NULL);