use mutex instead of semaphore in TPM driver

The TPM driver uses two semaphores as mutexes.  Use the mutex API instead of
the (binary) semaphores.

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Cc: Kylene Hall <kjhall@us.ibm.com>
Cc: Marcel Selhorst <tpm@selhorst.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 9f273f0..b2e2b00 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -21,6 +21,7 @@
 #include <linux/module.h>
 #include <linux/delay.h>
 #include <linux/fs.h>
+#include <linux/mutex.h>
 #include <linux/sched.h>
 #include <linux/miscdevice.h>
 #include <linux/platform_device.h>
@@ -94,11 +95,11 @@
 	/* Data passed to and from the tpm via the read/write calls */
 	u8 *data_buffer;
 	atomic_t data_pending;
-	struct semaphore buffer_mutex;
+	struct mutex buffer_mutex;
 
 	struct timer_list user_read_timer;	/* user needs to claim result */
 	struct work_struct work;
-	struct semaphore tpm_mutex;	/* tpm is processing */
+	struct mutex tpm_mutex;	/* tpm is processing */
 
 	struct tpm_vendor_specific vendor;