[WATCHDOG] add WDIOC_GETTIMELEFT ioctl

Some watchdog drivers have the ability to report the remaining time
before the system will reboot. With the WDIOC_GETTIMELEFT ioctl
you can now read the time left before the watchdog would reboot
your system.

The following drivers support this new IOCTL:
i8xx_tco.c, pcwd_pci.c and pcwd_usb.c .

Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>

5 files changed, 92 insertions, 5 deletions

diff --git a/Documentation/watchdog/watchdog-api.txt b/Documentation/watchdog/watchdog-api.txt
index 7dc2c1c6f779..d738ec25eaa4 100644
--- a/Documentation/watchdog/watchdog-api.txt
+++ b/Documentation/watchdog/watchdog-api.txt
@@ -134,6 +134,15 @@ There is also a get function for getting the pretimeout:
 
 Not all watchdog drivers will support a pretimeout.
 
+Get the number of seconds before reboot:
+
+Some watchdog drivers have the ability to report the remaining time
+before the system will reboot. The WDIOC_GETTIMELEFT is the ioctl
+that returns the number of seconds before reboot.
+
+    ioctl(fd, WDIOC_GETTIMELEFT, &timeleft);
+    printf("The timeout was is %d seconds\n", timeleft);
+
 Environmental monitoring:
 
 All watchdog drivers are required return more information about the system,
diff --git a/drivers/char/watchdog/i8xx_tco.c b/drivers/char/watchdog/i8xx_tco.c
index fa2ba9ebe42a..bfbdbbf3c2f2 100644
--- a/drivers/char/watchdog/i8xx_tco.c
+++ b/drivers/char/watchdog/i8xx_tco.c
@@ -205,6 +205,23 @@ static int tco_timer_set_heartbeat (int t)
         return 0;
 }
 
+static int tco_timer_get_timeleft (int *time_left)
+{
+        unsigned char val;
+
+        spin_lock(&tco_lock);
+
+        /* read the TCO Timer */
+        val = inb (TCO1_RLD);
+        val &= 0x3f;
+
+        spin_unlock(&tco_lock);
+
+        *time_left = (int)((val * 6) / 10);
+
+        return 0;
+}
+
 /*
  *      /dev/watchdog handling
  */
@@ -272,6 +289,7 @@ static int i8xx_tco_ioctl (struct inode *inode, struct file *file,
 {
         int new_options, retval = -EINVAL;
         int new_heartbeat;
+        int time_left;
         void __user *argp = (void __user *)arg;
         int __user *p = argp;
         static struct watchdog_info ident = {
@@ -320,7 +338,7 @@ static int i8xx_tco_ioctl (struct inode *inode, struct file *file,
                                 return -EFAULT;
 
                         if (tco_timer_set_heartbeat(new_heartbeat))
-                            return -EINVAL;
+                                return -EINVAL;
 
                         tco_timer_keepalive ();
                         /* Fall */
@@ -329,6 +347,14 @@ static int i8xx_tco_ioctl (struct inode *inode, struct file *file,
                 case WDIOC_GETTIMEOUT:
                         return put_user(heartbeat, p);
 
+                case WDIOC_GETTIMELEFT:
+                {
+                        if (tco_timer_get_timeleft(&time_left))
+                                return -EINVAL;
+
+                        return put_user(time_left, p);
+                }
+
                 default:
                         return -ENOIOCTLCMD;
         }
diff --git a/drivers/char/watchdog/pcwd_pci.c b/drivers/char/watchdog/pcwd_pci.c
index 2451edbefece..1f40ecefbf72 100644
--- a/drivers/char/watchdog/pcwd_pci.c
+++ b/drivers/char/watchdog/pcwd_pci.c
@@ -21,7 +21,7 @@
  */
 
 /*
- *      A bells and whistles driver is available from: 
+ *      A bells and whistles driver is available from:
  *      http://www.kernel.org/pub/linux/kernel/people/wim/pcwd/pcwd_pci/
  *
  *      More info available at http://www.berkprod.com/ or http://www.pcwatchdog.com/
@@ -390,6 +390,24 @@ static int pcipcwd_get_temperature(int *temperature)
         return 0;
 }
 
+static int pcipcwd_get_timeleft(int *time_left)
+{
+        int msb;
+        int lsb;
+
+        /* Read the time that's left before rebooting */
+        /* Note: if the board is not yet armed then we will read 0xFFFF */
+        send_command(CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
+
+        *time_left = (msb << 8) + lsb;
+
+        if (debug >= VERBOSE)
+                printk(KERN_DEBUG PFX "Time left before next reboot: %d\n",
+                       *time_left);
+
+        return 0;
+}
+
 /*
  *      /dev/watchdog handling
  */
@@ -512,6 +530,16 @@ static int pcipcwd_ioctl(struct inode *inode, struct file *file,
                 case WDIOC_GETTIMEOUT:
                         return put_user(heartbeat, p);
 
+                case WDIOC_GETTIMELEFT:
+                {
+                        int time_left;
+
+                        if (pcipcwd_get_timeleft(&time_left))
+                                return -EFAULT;
+
+                        return put_user(time_left, p);
+                }
+
                 default:
                         return -ENOIOCTLCMD;
         }
diff --git a/drivers/char/watchdog/pcwd_usb.c b/drivers/char/watchdog/pcwd_usb.c
index 3fdfda9324fa..0d072bed501d 100644
--- a/drivers/char/watchdog/pcwd_usb.c
+++ b/drivers/char/watchdog/pcwd_usb.c
@@ -317,6 +317,19 @@ static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, int *temp
         return 0;
 }
 
+static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd, int *time_left)
+{
+        unsigned char msb, lsb;
+
+        /* Read the time that's left before rebooting */
+        /* Note: if the board is not yet armed then we will read 0xFFFF */
+        usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
+
+        *time_left = (msb << 8) + lsb;
+
+        return 0;
+}
+
 /*
  *      /dev/watchdog handling
  */
@@ -422,6 +435,16 @@ static int usb_pcwd_ioctl(struct inode *inode, struct file *file,
                 case WDIOC_GETTIMEOUT:
                         return put_user(heartbeat, p);
 
+                case WDIOC_GETTIMELEFT:
+                {
+                        int time_left;
+
+                        if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
+                                return -EFAULT;
+
+                        return put_user(time_left, p);
+                }
+
                 default:
                         return -ENOIOCTLCMD;
         }
diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h
index a99c937f665e..011bcfeb9f09 100644
--- a/include/linux/watchdog.h
+++ b/include/linux/watchdog.h
@@ -30,6 +30,7 @@ struct watchdog_info {
 #define WDIOC_GETTIMEOUT        _IOR(WATCHDOG_IOCTL_BASE, 7, int)
 #define WDIOC_SETPRETIMEOUT     _IOWR(WATCHDOG_IOCTL_BASE, 8, int)
 #define WDIOC_GETPRETIMEOUT     _IOR(WATCHDOG_IOCTL_BASE, 9, int)
+#define WDIOC_GETTIMELEFT       _IOR(WATCHDOG_IOCTL_BASE, 10, int)
 
 #define WDIOF_UNKNOWN           -1      /* Unknown flag error */
 #define WDIOS_UNKNOWN           -1      /* Unknown status error */
@@ -40,9 +41,9 @@ struct watchdog_info {
 #define WDIOF_EXTERN2           0x0008  /* External relay 2 */
 #define WDIOF_POWERUNDER        0x0010  /* Power bad/power fault */
 #define WDIOF_CARDRESET         0x0020  /* Card previously reset the CPU */
-#define WDIOF_POWEROVER         0x0040  /* Power over voltage */
-#define WDIOF_SETTIMEOUT        0x0080  /* Set timeout (in seconds) */
-#define WDIOF_MAGICCLOSE        0x0100  /* Supports magic close char */
+#define WDIOF_POWEROVER         0x0040  /* Power over voltage */
+#define WDIOF_SETTIMEOUT        0x0080  /* Set timeout (in seconds) */
+#define WDIOF_MAGICCLOSE        0x0100  /* Supports magic close char */
 #define WDIOF_PRETIMEOUT        0x0200  /* Pretimeout (in seconds), get/set */
 #define WDIOF_KEEPALIVEPING     0x8000  /* Keep alive ping reply */