Re: Fwd: [PATCH 3/8] watchdog: davinci: add GET_TIMELEFT option support

From: ivan.khoronzhuk
Date: Mon Nov 18 2013 - 08:22:47 EST


On 11/17/2013 04:22 AM, Guenter Roeck wrote:
On 11/06/2013 03:31 AM, ivan.khoronzhuk wrote:
Currently, the davinci watchdog can be read while counting,
so we can add ability to report the remaining time before
the system will reboot.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxx>
---
drivers/watchdog/davinci_wdt.c | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)

diff --git a/drivers/watchdog/davinci_wdt.c
b/drivers/watchdog/davinci_wdt.c
index 1fc2093..6cbf2e1 100644
--- a/drivers/watchdog/davinci_wdt.c
+++ b/drivers/watchdog/davinci_wdt.c
@@ -117,6 +117,33 @@ static int davinci_wdt_ping(struct
watchdog_device *wdd)
return 0;
}

+static unsigned int davinci_wdt_get_timeleft(struct watchdog_device
*wdd)
+{
+ u64 timer_counter;
+ unsigned long freq;
+ u32 val;
+ struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd);
+
+ /* if timeout is occured then return 0 */

is -> has ?


Yes

+ val = ioread32(davinci_wdt->base + WDTCR);
+ if (val & WDFLAG)
+ return 0;
+
+ freq = clk_get_rate(davinci_wdt->clk);
+
+ if (!freq) {
+ dev_err(wdd->dev, "clock freq is not set\n");
+ return 0;
+ }
+
This error check doesn't make sense to me; elsewhere the clock rate is
not validated.
I would suggest to just return 0 here.


Agree

+ timer_counter = ioread32(davinci_wdt->base + TIM12);
+ timer_counter |= ((u64)ioread32(davinci_wdt->base + TIM34) << 32);
+
+ do_div(timer_counter, freq);
+
+ return wdd->timeout - timer_counter;
+}
+
static const struct watchdog_info davinci_wdt_info = {
.options = WDIOF_KEEPALIVEPING,
.identity = "DaVinci Watchdog",
@@ -127,6 +154,7 @@ static const struct watchdog_ops davinci_wdt_ops = {
.start = davinci_wdt_start,
.stop = davinci_wdt_ping,
.ping = davinci_wdt_ping,
+ .get_timeleft = davinci_wdt_get_timeleft,
};

static int davinci_wdt_probe(struct platform_device *pdev)




--
Regards,
Ivan Khoronzhuk
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