static irqreturn_t mfgpt_tick(int irq, void *dev_id)
{
u16 val = geode_mfgpt_read(mfgpt_event_clock, MFGPT_REG_SETUP);
/* See if the interrupt was for us */
if (!(val & (MFGPT_SETUP_SETUP | MFGPT_SETUP_CMP2 | MFGPT_SETUP_CMP1)))
return IRQ_NONE;
/* Turn off the clock (and clear the event) */
mfgpt_disable_timer(mfgpt_event_clock);
if (mfgpt_tick_mode == CLOCK_EVT_MODE_SHUTDOWN)
return IRQ_HANDLED;
/* Clear the counter */
geode_mfgpt_write(mfgpt_event_clock, MFGPT_REG_COUNTER, 0);
/* Restart the clock in periodic mode */
if (mfgpt_tick_mode == CLOCK_EVT_MODE_PERIODIC) {
geode_mfgpt_write(mfgpt_event_clock, MFGPT_REG_SETUP,
MFGPT_SETUP_CNTEN | MFGPT_SETUP_CMP2);
}
mfgpt_clockevent.event_handler(&mfgpt_clockevent);
return IRQ_HANDLED;
}
static void mfgpt_start_timer(u16 delta)
{
geode_mfgpt_write(mfgpt_event_clock, MFGPT_REG_CMP2, (u16) delta);
geode_mfgpt_write(mfgpt_event_clock, MFGPT_REG_COUNTER, 0);
geode_mfgpt_write(mfgpt_event_clock, MFGPT_REG_SETUP,
MFGPT_SETUP_CNTEN | MFGPT_SETUP_CMP2);
}
static void geodewdt_ping(void)
{
/* Stop the counter */
geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, 0);
/* Reset the counter */
geode_mfgpt_write(wdt_timer, MFGPT_REG_COUNTER, 0);
/* Enable the counter */
geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, MFGPT_SETUP_CNTEN);
}
static int geodewdt_set_heartbeat(int val)
{
if (val < 1 || val > GEODEWDT_MAX_SECONDS)
return -EINVAL;
geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, 0);
geode_mfgpt_write(wdt_timer, MFGPT_REG_CMP2, val * GEODEWDT_HZ);
geode_mfgpt_write(wdt_timer, MFGPT_REG_COUNTER, 0);
geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, MFGPT_SETUP_CNTEN);
timeout = val;
return 0;
}
int __init mfgpt_timer_setup(void)
{
int timer, ret;
u16 val;
timer = geode_mfgpt_alloc_timer(MFGPT_TIMER_ANY, MFGPT_DOMAIN_WORKING);
if (timer < 0) {
printk(KERN_ERR
"mfgpt-timer: Could not allocate a MFPGT timer\n");
return -ENODEV;
}
mfgpt_event_clock = timer;
/* Set up the IRQ on the MFGPT side */
if (geode_mfgpt_setup_irq(mfgpt_event_clock, MFGPT_CMP2, irq)) {
printk(KERN_ERR "mfgpt-timer: Could not set up IRQ %d\n", irq);
return -EIO;
}
/* And register it with the kernel */
ret = setup_irq(irq, &mfgptirq);
if (ret) {
printk(KERN_ERR
"mfgpt-timer: Unable to set up the interrupt.\n");
goto err;
}
/* Set the clock scale and enable the event mode for CMP2 */
val = MFGPT_SCALE | (3 << 8);
geode_mfgpt_write(mfgpt_event_clock, MFGPT_REG_SETUP, val);
/* Set up the clock event */
mfgpt_clockevent.mult = div_sc(MFGPT_HZ, NSEC_PER_SEC,
mfgpt_clockevent.shift);
mfgpt_clockevent.min_delta_ns = clockevent_delta2ns(0xF,
&mfgpt_clockevent);
mfgpt_clockevent.max_delta_ns = clockevent_delta2ns(0xFFFE,
&mfgpt_clockevent);
printk(KERN_INFO
"mfgpt-timer: registering the MFGPT timer as a clock event.\n");
clockevents_register_device(&mfgpt_clockevent);
return 0;
err:
geode_mfgpt_release_irq(mfgpt_event_clock, MFGPT_CMP2, irq);
printk(KERN_ERR
"mfgpt-timer: Unable to set up the MFGPT clock source\n");
return -EIO;
}
static void geodewdt_disable(void)
{
geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, 0);
geode_mfgpt_write(wdt_timer, MFGPT_REG_COUNTER, 0);
}
static long geodewdt_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
void __user *argp = (void __user *)arg;
int __user *p = argp;
int interval;
static struct watchdog_info ident = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING
| WDIOF_MAGICCLOSE,
.firmware_version = 1,
.identity = WATCHDOG_NAME,
};
switch (cmd) {
case WDIOC_GETSUPPORT:
return copy_to_user(argp, &ident,
sizeof(ident)) ? -EFAULT : 0;
break;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
return put_user(0, p);
case WDIOC_SETOPTIONS:
{
int options, ret = -EINVAL;
if (get_user(options, p))
return -EFAULT;
if (options & WDIOS_DISABLECARD) {
geodewdt_disable();
ret = 0;
}
if (options & WDIOS_ENABLECARD) {
geodewdt_ping();
ret = 0;
}
return ret;
}
case WDIOC_KEEPALIVE:
geodewdt_ping();
return 0;
case WDIOC_SETTIMEOUT:
if (get_user(interval, p))
return -EFAULT;
if (geodewdt_set_heartbeat(interval))
return -EINVAL;
/* Fall through */
case WDIOC_GETTIMEOUT:
return put_user(timeout, p);
default:
return -ENOTTY;
}
return 0;
}
static const struct file_operations geodewdt_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = geodewdt_write,
.unlocked_ioctl = geodewdt_ioctl,
.open = geodewdt_open,
.release = geodewdt_release,
};
static struct miscdevice geodewdt_miscdev = {
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &geodewdt_fops,
};
static int __devinit geodewdt_probe(struct platform_device *dev)
{
int ret, timer;
timer = geode_mfgpt_alloc_timer(MFGPT_TIMER_ANY, MFGPT_DOMAIN_WORKING);
if (timer == -1) {
printk(KERN_ERR "geodewdt: No timers were available\n");
return -ENODEV;
}
wdt_timer = timer;
/* Set up the timer */
geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP,
GEODEWDT_SCALE | (3 << 8));
/* Set up comparator 2 to reset when the event fires */
geode_mfgpt_toggle_event(wdt_timer, MFGPT_CMP2, MFGPT_EVENT_RESET, 1);
/* Set up the initial timeout */
geode_mfgpt_write(wdt_timer, MFGPT_REG_CMP2,
timeout * GEODEWDT_HZ);
ret = misc_register(&geodewdt_miscdev);
return ret;
}
static int __devexit geodewdt_remove(struct platform_device *dev)
{
misc_deregister(&geodewdt_miscdev);
return 0;
}
static void mfgpt_disable_timer(u16 clock)
{
/* avoid races by clearing CMP1 and CMP2 unconditionally */
geode_mfgpt_write(clock, MFGPT_REG_SETUP, (u16) ~MFGPT_SETUP_CNTEN |
MFGPT_SETUP_CMP1 | MFGPT_SETUP_CMP2);
}
