[WATCHDOG] mv64x60_wdt: Support for WDIOC_SETTIMEOUT ioctl
Add the ability to modify the watchdog timer timeout interval.
Signed-off-by: Dale Farnsworth <dale@farnsworth.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
diff --git a/drivers/char/watchdog/mv64x60_wdt.c b/drivers/char/watchdog/mv64x60_wdt.c
index 420c7b8..e990e3a 100644
--- a/drivers/char/watchdog/mv64x60_wdt.c
+++ b/drivers/char/watchdog/mv64x60_wdt.c
@@ -43,6 +43,7 @@
static int wdt_status;
static void __iomem *mv64x60_wdt_regs;
static int mv64x60_wdt_timeout;
+static unsigned int bus_clk;
static void mv64x60_wdt_reg_write(u32 val)
{
@@ -82,6 +83,18 @@
}
}
+static void mv64x60_wdt_set_timeout(int timeout)
+{
+ /* maximum bus cycle count is 0xFFFFFFFF */
+ if (timeout > 0xFFFFFFFF / bus_clk)
+ timeout = 0xFFFFFFFF / bus_clk;
+
+ mv64x60_wdt_timeout = timeout;
+ writel((timeout * bus_clk) >> 8,
+ mv64x60_wdt_regs + MV64x60_WDT_WDC_OFFSET);
+ mv64x60_wdt_service();
+}
+
static int mv64x60_wdt_open(struct inode *inode, struct file *file)
{
if (test_and_set_bit(MV64x60_WDOG_FLAG_OPENED, &wdt_flags))
@@ -118,9 +131,11 @@
static int mv64x60_wdt_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
+ int timeout;
void __user *argp = (void __user *)arg;
static struct watchdog_info info = {
- .options = WDIOF_KEEPALIVEPING,
+ .options = WDIOF_SETTIMEOUT |
+ WDIOF_KEEPALIVEPING,
.firmware_version = 0,
.identity = "MV64x60 watchdog",
};
@@ -150,7 +165,10 @@
break;
case WDIOC_SETTIMEOUT:
- return -EOPNOTSUPP;
+ if (get_user(timeout, (int __user *)argp))
+ return -EFAULT;
+ mv64x60_wdt_set_timeout(timeout);
+ /* Fall through */
case WDIOC_GETTIMEOUT:
if (put_user(mv64x60_wdt_timeout, (int __user *)argp))
@@ -182,15 +200,22 @@
static int __devinit mv64x60_wdt_probe(struct platform_device *dev)
{
struct mv64x60_wdt_pdata *pdata = dev->dev.platform_data;
- int bus_clk = 133;
struct resource *r;
+ int timeout = 10;
- mv64x60_wdt_timeout = 10;
+ bus_clk = 133; /* in MHz */
if (pdata) {
- mv64x60_wdt_timeout = pdata->timeout;
+ timeout = pdata->timeout;
bus_clk = pdata->bus_clk;
}
+ /* Since bus_clk is truncated MHz, actual frequency could be
+ * up to 1MHz higher. Round up, since it's better to time out
+ * too late than too soon.
+ */
+ bus_clk++;
+ bus_clk *= 1000000; /* convert to Hz */
+
r = platform_get_resource(dev, IORESOURCE_MEM, 0);
if (!r)
return -ENODEV;
@@ -199,8 +224,7 @@
if (mv64x60_wdt_regs == NULL)
return -ENOMEM;
- writel((mv64x60_wdt_timeout * (bus_clk * 1000000)) >> 8,
- mv64x60_wdt_regs + MV64x60_WDT_WDC_OFFSET);
+ mv64x60_wdt_set_timeout(timeout);
return misc_register(&mv64x60_wdt_miscdev);
}