Re: [PATCH 7/7] watchdog: s3c2410: Let kernel kick watchdog

From: Krzysztof Kozlowski
Date: Fri Oct 29 2021 - 04:20:51 EST


On 28/10/2021 20:35, Sam Protsenko wrote:
> When "tmr_atboot" module param is set, the watchdog is started in
> driver's probe. In that case, also set WDOG_HW_RUNNING bit to let
> watchdog core driver know it's running. This way wathcdog core can kick

s/wathcdog/watchdog/

> the watchdog for us (if CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED option is
> enabled), until user space takes control.

This does not explain why you move the code around. I guess you miss
here information that we should start the watchdog before registering
it? If so please explain why.

>
> Signed-off-by: Sam Protsenko <semen.protsenko@xxxxxxxxxx>
> ---
> drivers/watchdog/s3c2410_wdt.c | 26 +++++++++++++++-----------
> 1 file changed, 15 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
> index ca082b1226e3..9af014ff1468 100644
> --- a/drivers/watchdog/s3c2410_wdt.c
> +++ b/drivers/watchdog/s3c2410_wdt.c
> @@ -732,6 +732,21 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
> wdt->wdt_device.bootstatus = s3c2410wdt_get_bootstatus(wdt);
> wdt->wdt_device.parent = dev;
>
> + /*
> + * If "tmr_atboot" param is non-zero, start the watchdog right now. Also
> + * set WDOG_HW_RUNNING bit, so that watchdog core can kick the watchdog.
> + *
> + * If we're not enabling the watchdog, then ensure it is disabled if it
> + * has been left running from the bootloader or other source.
> + */
> + if (tmr_atboot && started == 0) {
> + dev_info(dev, "starting watchdog timer\n");
> + s3c2410wdt_start(&wdt->wdt_device);
> + set_bit(WDOG_HW_RUNNING, &wdt->wdt_device.status);
> + } else if (!tmr_atboot) {
> + s3c2410wdt_stop(&wdt->wdt_device);
> + }
> +
> ret = watchdog_register_device(&wdt->wdt_device);
> if (ret)
> goto err_cpufreq;
> @@ -740,17 +755,6 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
> if (ret < 0)
> goto err_unregister;
>
> - if (tmr_atboot && started == 0) {
> - dev_info(dev, "starting watchdog timer\n");
> - s3c2410wdt_start(&wdt->wdt_device);
> - } else if (!tmr_atboot) {
> - /* if we're not enabling the watchdog, then ensure it is
> - * disabled if it has been left running from the bootloader
> - * or other source */
> -
> - s3c2410wdt_stop(&wdt->wdt_device);
> - }
> -
> platform_set_drvdata(pdev, wdt);
>
> /* print out a statement of readiness */
>


Best regards,
Krzysztof