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-rw-r--r--drivers/watchdog/s3c2410_wdt.c16
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
index d57f19b5077f..59e95762a6de 100644
--- a/drivers/watchdog/s3c2410_wdt.c
+++ b/drivers/watchdog/s3c2410_wdt.c
@@ -47,6 +47,8 @@
#define S3C2410_WTDAT 0x04
#define S3C2410_WTCNT 0x08
+#define S3C2410_WTCNT_MAXCNT 0xffff
+
#define S3C2410_WTCON_RSTEN (1 << 0)
#define S3C2410_WTCON_INTEN (1 << 2)
#define S3C2410_WTCON_ENABLE (1 << 5)
@@ -56,8 +58,11 @@
#define S3C2410_WTCON_DIV64 (2 << 3)
#define S3C2410_WTCON_DIV128 (3 << 3)
+#define S3C2410_WTCON_MAXDIV 0x80
+
#define S3C2410_WTCON_PRESCALE(x) ((x) << 8)
#define S3C2410_WTCON_PRESCALE_MASK (0xff << 8)
+#define S3C2410_WTCON_PRESCALE_MAX 0xff
#define CONFIG_S3C2410_WATCHDOG_ATBOOT (0)
#define CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME (15)
@@ -198,6 +203,14 @@ do { \
/* functions */
+static inline unsigned int s3c2410wdt_max_timeout(struct clk *clock)
+{
+ unsigned long freq = clk_get_rate(clock);
+
+ return S3C2410_WTCNT_MAXCNT / (freq / (S3C2410_WTCON_PRESCALE_MAX + 1)
+ / S3C2410_WTCON_MAXDIV);
+}
+
static inline struct s3c2410_wdt *freq_to_wdt(struct notifier_block *nb)
{
return container_of(nb, struct s3c2410_wdt, freq_transition);
@@ -568,6 +581,9 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
return ret;
}
+ wdt->wdt_device.min_timeout = 1;
+ wdt->wdt_device.max_timeout = s3c2410wdt_max_timeout(wdt->clock);
+
ret = s3c2410wdt_cpufreq_register(wdt);
if (ret < 0) {
dev_err(dev, "failed to register cpufreq\n");