1 files changed, 11 insertions, 5 deletions

diff --git a/drivers/char/dsp56k.c b/drivers/char/dsp56k.c
index d716c78f0ff4..b9a30c30e2b8 100644
--- a/drivers/char/dsp56k.c
+++ b/drivers/char/dsp56k.c
@@ -33,6 +33,7 @@
 #include <linux/mm.h>
 #include <linux/init.h>
 #include <linux/device.h>
+#include <linux/smp_lock.h>
 #include <linux/firmware.h>
 #include <linux/platform_device.h>
 
@@ -417,13 +418,17 @@ static unsigned int dsp56k_poll(struct file *file, poll_table *wait)
 static int dsp56k_open(struct inode *inode, struct file *file)
 {
         int dev = iminor(inode) & 0x0f;
+        int ret = 0;
 
+        lock_kernel();
         switch(dev)
         {
         case DSP56K_DEV_56001:
 
-                if (test_and_set_bit(0, &dsp56k.in_use))
-                        return -EBUSY;
+                if (test_and_set_bit(0, &dsp56k.in_use)) {
+                        ret = -EBUSY;
+                        goto out;
+                }
 
                 dsp56k.timeout = TIMEOUT;
                 dsp56k.maxio = MAXIO;
@@ -439,10 +444,11 @@ static int dsp56k_open(struct inode *inode, struct file *file)
                 break;
 
         default:
-                return -ENODEV;
+                ret = -ENODEV;
         }
-
-        return 0;
+out:
+        unlock_kernel();
+        return ret;
 }
 
 static int dsp56k_release(struct inode *inode, struct file *file)