watchdog: it87_wdt: Add support for watchdogs with 8b timers

This patch adds support for watchdogs with 8b timers, like ones in
IT8702F and older revisions of IT8712F Super IO chip, to it87_wdt
driver. This patch should be used after the patch
'it87_wdt: Add support for IT8720F watchdog'.

Signed-off-by: Ondrej Zajicek <santiago@crfreenet.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

2 files changed, 63 insertions, 28 deletions

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index cc53136122f9..5a5c024482fa 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -565,11 +565,11 @@ config IT87_WDT
         tristate "IT87 Watchdog Timer"
         depends on X86 && EXPERIMENTAL
         ---help---
-          This is the driver for the hardware watchdog on the ITE
-          IT8716, IT8718, IT8720, IT8726, IT8712(Version J,K) Super I/O
-          chips. This watchdog simply watches your kernel to make sure
-          it doesn't freeze, and if it does, it reboots your computer
-          after a certain amount of time.
+          This is the driver for the hardware watchdog on the ITE IT8702,
+          IT8712, IT8716, IT8718, IT8720, IT8726, IT8712 Super I/O chips.
+          This watchdog simply watches your kernel to make sure it doesn't
+          freeze, and if it does, it reboots your computer after a certain
+          amount of time.
 
           To compile this driver as a module, choose M here: the module will
           be called it87_wdt.
diff --git a/drivers/watchdog/it87_wdt.c b/drivers/watchdog/it87_wdt.c
index 455de7714618..dad29245a6a7 100644
--- a/drivers/watchdog/it87_wdt.c
+++ b/drivers/watchdog/it87_wdt.c
@@ -12,7 +12,7 @@
  *                  http://www.ite.com.tw/
  *
  *      Support of the watchdog timers, which are available on
- *      IT8716, IT8718, IT8720, IT8726 and IT8712 (J,K version).
+ *      IT8702, IT8712, IT8716, IT8718, IT8720 and IT8726.
  *
  *      This program is free software; you can redistribute it and/or
  *      modify it under the terms of the GNU General Public License
@@ -76,6 +76,7 @@
 
 /* Chip Id numbers */
 #define NO_DEV_ID       0xffff
+#define IT8702_ID       0x8702
 #define IT8705_ID       0x8705
 #define IT8712_ID       0x8712
 #define IT8716_ID       0x8716
@@ -133,7 +134,7 @@
 #define WDTS_USE_GP     4
 #define WDTS_EXPECTED   5
 
-static  unsigned int base, gpact, ciract;
+static  unsigned int base, gpact, ciract, max_units;
 static  unsigned long wdt_status;
 static  DEFINE_SPINLOCK(spinlock);
 
@@ -211,6 +212,33 @@ static inline void superio_outw(int val, int reg)
         outb(val, VAL);
 }
 
+/* Internal function, should be called after superio_select(GPIO) */
+static void wdt_update_timeout(void)
+{
+        unsigned char cfg = WDT_KRST | WDT_PWROK;
+        int tm = timeout;
+
+        if (testmode)
+                cfg = 0;
+
+        if (tm <= max_units)
+                cfg |= WDT_TOV1;
+        else
+                tm /= 60;
+
+        superio_outb(cfg, WDTCFG);
+        superio_outb(tm, WDTVALLSB);
+        if (max_units > 255)
+                superio_outb(tm>>8, WDTVALMSB);
+}
+
+static int wdt_round_time(int t)
+{
+        t += 59;
+        t -= t % 60;
+        return t;
+}
+
 /* watchdog timer handling */
 
 static void wdt_keepalive(void)
@@ -235,12 +263,7 @@ static void wdt_start(void)
                 superio_outb(WDT_GAMEPORT, WDTCTRL);
         else
                 superio_outb(WDT_CIRINT, WDTCTRL);
-        if (!testmode)
-                superio_outb(WDT_TOV1 | WDT_KRST | WDT_PWROK, WDTCFG);
-        else
-                superio_outb(WDT_TOV1, WDTCFG);
-        superio_outb(timeout>>8, WDTVALMSB);
-        superio_outb(timeout, WDTVALLSB);
+        wdt_update_timeout();
 
         superio_exit();
         spin_unlock_irqrestore(&spinlock, flags);
@@ -256,8 +279,9 @@ static void wdt_stop(void)
         superio_select(GPIO);
         superio_outb(0x00, WDTCTRL);
         superio_outb(WDT_TOV1, WDTCFG);
-        superio_outb(0x00, WDTVALMSB);
         superio_outb(0x00, WDTVALLSB);
+        if (max_units > 255)
+                superio_outb(0x00, WDTVALMSB);
 
         superio_exit();
         spin_unlock_irqrestore(&spinlock, flags);
@@ -267,8 +291,8 @@ static void wdt_stop(void)
  *      wdt_set_timeout - set a new timeout value with watchdog ioctl
  *      @t: timeout value in seconds
  *
- *      The hardware device has a 16 bit watchdog timer, thus the
- *      timeout time ranges between 1 and 65535 seconds.
+ *      The hardware device has a 8 or 16 bit watchdog timer (depends on
+ *      chip version) that can be configured to count seconds or minutes.
  *
  *      Used within WDIOC_SETTIMEOUT watchdog device ioctl.
  */
@@ -277,19 +301,19 @@ static int wdt_set_timeout(int t)
 {
         unsigned long flags;
 
-        if (t < 1 || t > 65535)
+        if (t < 1 || t > max_units * 60)
                 return -EINVAL;
 
-        timeout = t;
+        if (t > max_units)
+                timeout = wdt_round_time(t);
+        else
+                timeout = t;
 
         spin_lock_irqsave(&spinlock, flags);
         if (test_bit(WDTS_TIMER_RUN, &wdt_status)) {
                 superio_enter();
-
                 superio_select(GPIO);
-                superio_outb(t>>8, WDTVALMSB);
-                superio_outb(t, WDTVALLSB);
-
+                wdt_update_timeout();
                 superio_exit();
         }
         spin_unlock_irqrestore(&spinlock, flags);
@@ -535,6 +559,8 @@ static int __init it87_wdt_init(void)
         u8  chip_rev;
         unsigned long flags;
 
+        wdt_status = 0;
+
         spin_lock_irqsave(&spinlock, flags);
         superio_enter();
         chip_type = superio_inw(CHIPID);
@@ -543,16 +569,21 @@ static int __init it87_wdt_init(void)
         spin_unlock_irqrestore(&spinlock, flags);
 
         switch (chip_type) {
+        case IT8702_ID:
+                max_units = 255;
+                break;
+        case IT8712_ID:
+                max_units = (chip_rev < 8) ? 255 : 65535;
+                break;
         case IT8716_ID:
         case IT8726_ID:
+                max_units = 65535;
                 break;
         case IT8718_ID:
         case IT8720_ID:
+                max_units = 65535;
                 try_gameport = 0;
                 break;
-        case IT8712_ID:
-                if (chip_rev > 7)
-                        break;
         case IT8705_ID:
                 printk(KERN_ERR PFX
                        "Unsupported Chip found, Chip %04x Revision %02x\n",
@@ -628,13 +659,16 @@ static int __init it87_wdt_init(void)
                 spin_unlock_irqrestore(&spinlock, flags);
         }
 
-        if (timeout < 1 || timeout > 65535) {
+        if (timeout < 1 || timeout > max_units * 60) {
                 timeout = DEFAULT_TIMEOUT;
                 printk(KERN_WARNING PFX
                        "Timeout value out of range, use default %d sec\n",
                        DEFAULT_TIMEOUT);
         }
 
+        if (timeout > max_units)
+                timeout = wdt_round_time(timeout);
+
         rc = register_reboot_notifier(&wdt_notifier);
         if (rc) {
                 printk(KERN_ERR PFX
@@ -661,7 +695,7 @@ static int __init it87_wdt_init(void)
                 outb(0x09, CIR_IER(base));
         }
 
-        printk(KERN_INFO PFX "Chip it%04x revision %d initialized. "
+        printk(KERN_INFO PFX "Chip IT%04x revision %d initialized. "
                 "timeout=%d sec (nowayout=%d testmode=%d exclusive=%d "
                 "nogameport=%d)\n", chip_type, chip_rev, timeout,
                 nowayout, testmode, exclusive, nogameport);
@@ -703,8 +737,9 @@ static void __exit it87_wdt_exit(void)
         superio_select(GPIO);
         superio_outb(0x00, WDTCTRL);
         superio_outb(0x00, WDTCFG);
-        superio_outb(0x00, WDTVALMSB);
         superio_outb(0x00, WDTVALLSB);
+        if (max_units > 255)
+                superio_outb(0x00, WDTVALMSB);
         if (test_bit(WDTS_USE_GP, &wdt_status)) {
                 superio_select(GAMEPORT);
                 superio_outb(gpact, ACTREG);