[PATCH] it87_wdt: Add support for watchdogs with 8b timers

Ondrej Zajicek
2010-09-14T00:45:59Z

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>

---

diff -uprN b/drivers/watchdog/Kconfig c/drivers/watchdog/Kconfig
--- b/drivers/watchdog/Kconfig 2010-09-13 19:03:43.000000000 +0200
+++ c/drivers/watchdog/Kconfig 2010-09-14 01:46:50.000000000 +0200
@@ -547,11 +547,11 @@ 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 -uprN b/drivers/watchdog/it87_wdt.c c/drivers/watchdog/it87_wdt.c
--- b/drivers/watchdog/it87_wdt.c 2010-09-13 22:31:48.000000000 +0200
+++ c/drivers/watchdog/it87_wdt.c 2010-09-14 02:11:44.000000000 +0200
@@ -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,
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);

--
Elen sila lumenn' omentielvo

Ondrej 'SanTiago' Zajicek (email: santiago@crfreenet.org)
OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net)
"To err is human -- to blame it on a computer is even more so."