1 files changed, 9 insertions, 1 deletions

diff --git a/drivers/char/watchdog/w83627hf_wdt.c b/drivers/char/watchdog/w83627hf_wdt.c
index 13f16d41c2fd..07d4bff27226 100644
--- a/drivers/char/watchdog/w83627hf_wdt.c
+++ b/drivers/char/watchdog/w83627hf_wdt.c
@@ -33,6 +33,7 @@
 #include <linux/notifier.h>
 #include <linux/reboot.h>
 #include <linux/init.h>
+#include <linux/spinlock.h>
 
 #include <asm/io.h>
 #include <asm/uaccess.h>
@@ -44,6 +45,7 @@
 
 static unsigned long wdt_is_open;
 static char expect_close;
+static spinlock_t io_lock;
 
 /* You must set this - there is no sane way to probe for this board. */
 static int wdt_io = 0x2E;
@@ -110,12 +112,16 @@ w83627hf_init(void)
 static void
 wdt_ctrl(int timeout)
 {
+        spin_lock(&io_lock);
+        
         w83627hf_select_wd_register();
 
         outb_p(0xF6, WDT_EFER);    /* Select CRF6 */
         outb_p(timeout, WDT_EFDR); /* Write Timeout counter to CRF6 */
 
         w83627hf_unselect_wd_register();
+
+        spin_unlock(&io_lock);
 }
 
 static int
@@ -223,7 +229,7 @@ wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
         }
 
         default:
-          return -ENOIOCTLCMD;
+          return -ENOTTY;
         }
         return 0;
 }
@@ -303,6 +309,8 @@ wdt_init(void)
 {
         int ret;
 
+        spin_lock_init(&io_lock);
+
         printk(KERN_INFO "WDT driver for the Winbond(TM) W83627HF Super I/O chip initialising.\n");
 
         if (wdt_set_heartbeat(timeout)) {