1 files changed, 4 insertions, 4 deletions

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index ae766d868454..ceba6082bd96 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -954,13 +954,16 @@ EXPORT_SYMBOL_GPL(tpm_store_cancel);
 
 /*
  * Device file system interface to the TPM
+ *
+ * It's assured that the chip will be opened just once,
+ * by the check of is_open variable, which is protected
+ * by driver_lock.
  */
 int tpm_open(struct inode *inode, struct file *file)
 {
         int rc = 0, minor = iminor(inode);
         struct tpm_chip *chip = NULL, *pos;
 
-        lock_kernel();
         spin_lock(&driver_lock);
 
         list_for_each_entry(pos, &tpm_chip_list, list) {
@@ -990,19 +993,16 @@ int tpm_open(struct inode *inode, struct file *file)
         if (chip->data_buffer == NULL) {
                 chip->num_opens--;
                 put_device(chip->dev);
-                unlock_kernel();
                 return -ENOMEM;
         }
 
         atomic_set(&chip->data_pending, 0);
 
         file->private_data = chip;
-        unlock_kernel();
         return 0;
 
 err_out:
         spin_unlock(&driver_lock);
-        unlock_kernel();
         return rc;
 }
 EXPORT_SYMBOL_GPL(tpm_open);