[PATCH] tpm: read return code issue

Replace an erroneous return code for the read function when no data is
available.

Signed-of-by: Kylene Hall <kjhall@us.ibm.com>

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 10 insertions, 20 deletions

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index ff170963c64..7b1f67d9f30 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -489,29 +489,19 @@ ssize_t tpm_read(struct file * file, char __user * buf,
                  size_t size, loff_t * off)
 {
         struct tpm_chip *chip = file->private_data;
-        int ret_size = -ENODATA;
+        int ret_size;
 
-        if (atomic_read(&chip->data_pending) != 0) {    /* Result available */
-                down(&chip->timer_manipulation_mutex);
-                del_singleshot_timer_sync(&chip->user_read_timer);
-                up(&chip->timer_manipulation_mutex);
+        del_singleshot_timer_sync(&chip->user_read_timer);
+        ret_size = atomic_read(&chip->data_pending);
+        atomic_set(&chip->data_pending, 0);
+        if (ret_size > 0) {     /* relay data */
+                if (size < ret_size)
+                        ret_size = size;
 
                 down(&chip->buffer_mutex);
-
-                ret_size = atomic_read(&chip->data_pending);
-                atomic_set(&chip->data_pending, 0);
-
-                if (ret_size == 0)      /* timeout just occurred */
-                        ret_size = -ETIME;
-                else if (ret_size > 0) {        /* relay data */
-                        if (size < ret_size)
-                                ret_size = size;
-
-                        if (copy_to_user((void __user *) buf,
-                                         chip->data_buffer, ret_size)) {
-                                ret_size = -EFAULT;
-                        }
-                }
+                if (copy_to_user
+                    ((void __user *) buf, chip->data_buffer, ret_size))
+                        ret_size = -EFAULT;
                 up(&chip->buffer_mutex);
         }