2015-06-17 09:09:10

by Lars Poeschel

Subject: [PATCH] watchdog: omap_wdt: implement get_timeleft

From: Lars Poeschel <[email protected]>

The omap watchdog hardware is able to read the watchdog timer counter
register. This implements this functionality in the omap_wdt driver, so
one is can read the time until the watchdog will trigger the reset in
seconds using WDIOC_GETTIMELEFT.

Signed-off-by: Lars Poeschel <[email protected]>
---
drivers/watchdog/omap_wdt.c | 11 +++++++++++
drivers/watchdog/omap_wdt.h | 1 +
2 files changed, 12 insertions(+)

diff --git a/drivers/watchdog/omap_wdt.c b/drivers/watchdog/omap_wdt.c
index 1e6be9e..2480a27 100644
--- a/drivers/watchdog/omap_wdt.c
+++ b/drivers/watchdog/omap_wdt.c
@@ -188,6 +188,16 @@ static int omap_wdt_set_timeout(struct watchdog_device *wdog,
return 0;
}

+static unsigned int omap_wdt_get_timeleft(struct watchdog_device *wdog)
+{
+ struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog);
+ void __iomem *base = wdev->base;
+ u32 value;
+
+ value = readl_relaxed(base + OMAP_WATCHDOG_CRR);
+ return GET_WCCR_SECS(value);
+}
+
static const struct watchdog_info omap_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
.identity = "OMAP Watchdog",
@@ -199,6 +209,7 @@ static const struct watchdog_ops omap_wdt_ops = {
.stop = omap_wdt_stop,
.ping = omap_wdt_ping,
.set_timeout = omap_wdt_set_timeout,
+ .get_timeleft = omap_wdt_get_timeleft,
};

static int omap_wdt_probe(struct platform_device *pdev)
diff --git a/drivers/watchdog/omap_wdt.h b/drivers/watchdog/omap_wdt.h
index 09b774c..42f31ec 100644
--- a/drivers/watchdog/omap_wdt.h
+++ b/drivers/watchdog/omap_wdt.h
@@ -50,5 +50,6 @@

#define PTV 0 /* prescale */
#define GET_WLDR_VAL(secs) (0xffffffff - ((secs) * (32768/(1<<PTV))) + 1)
+#define GET_WCCR_SECS(val) ((0xffffffff - (val) + 1) / (32768/(1<<PTV)))

#endif /* _OMAP_WATCHDOG_H */
--
2.1.4

2015-06-18 16:38:42

by Guenter Roeck

Subject: Re: watchdog: omap_wdt: implement get_timeleft

On Wed, Jun 17, 2015 at 10:58:59AM +0200, [email protected] wrote:
> From: Lars Poeschel <[email protected]>
>
> The omap watchdog hardware is able to read the watchdog timer counter
> register. This implements this functionality in the omap_wdt driver, so
> one is can read the time until the watchdog will trigger the reset in
> seconds using WDIOC_GETTIMELEFT.
>
> Signed-off-by: Lars Poeschel <[email protected]>

Reviewed-by: Guenter Roeck <[email protected]>