Hi Marco,
Thanks.
Acked-by: Steve Twiss <stwiss.opensource@xxxxxxxxxxx>
Regards,
Stephen
On 17 May 2018 08:04, Marco Felsch wrote:
> Subject: [PATCH v3] watchdog: da9063: Fix setting/changing timeout
>
> If the timeout value is set more than once the DA9063 watchdog triggers
> a reset signal which reset the system.
>
> To update the timeout value we have to disable the watchdog, clear the
> watchdog counter value and write the new timeout value to the watchdog.
> Clearing the counter value is a feature to be on the safe side because the
> data sheet doesn't describe the behaviour of the watchdog counter value
> after a watchdog disabling-enable-sequence.
>
> The patch is based on Philipp Zabel's previous patch but doesn't wait
> 150us because the DA9063 doesn't need this delay.
>
> Fixes: 5e9c16e37608 ("watchdog: Add DA9063 PMIC watchdog driver.")
> Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> ---
> drivers/watchdog/da9063_wdt.c | 35
> +++++++++++++++++++++++++++++++++--
> 1 file changed, 33 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/watchdog/da9063_wdt.c
> b/drivers/watchdog/da9063_wdt.c
> index b17ac1bb1f28..06fcc662673e 100644
> --- a/drivers/watchdog/da9063_wdt.c
> +++ b/drivers/watchdog/da9063_wdt.c
> @@ -45,8 +45,40 @@ static unsigned int
> da9063_wdt_timeout_to_sel(unsigned int secs)
> return DA9063_TWDSCALE_MAX;
> }
>
> +/*
> + * Writing a '1' to the self-clearing WATCHDOG bit resets the watchdog counter
> + * value.
> + */
> +static int _da9063_wdt_reset_timer(struct da9063 *da9063)
> +{
> + return regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
> + DA9063_WATCHDOG);
> +}
> +
> static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval)
> {
> + int ret;
> +
> + /*
> + * The watchdog triggers a reboot if a timeout value is already
> + * programmed. The reason for this is that the timeout value
> + * combines two functions in one: indicating the counter limit and
> + * starting the watchdog. The watchdog must be disabled to be able to
> + * change the timeout value if the watchdog is already running. Then
> + * we can set the new timeout value which enables the watchdog again.
> + */
> + ret = regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
> + DA9063_TWDSCALE_MASK, DA9063_TWDSCALE_DISABLE);
> + if (ret)
> + dev_warn(da9063->dev,
> + "Failed to disable watchdog before setting new timeout\n");
> +
> + usleep_range(150, 300);
> +
> + ret = _da9063_wdt_reset_timer(da9063);
> + if (ret)
> + dev_warn(da9063->dev, "Failed to reset watchdog counter\n");
> +
> return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
> DA9063_TWDSCALE_MASK, regval);
> }
> @@ -85,8 +117,7 @@ static int da9063_wdt_ping(struct watchdog_device
> *wdd)
> struct da9063 *da9063 = watchdog_get_drvdata(wdd);
> int ret;
>
> - ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
> - DA9063_WATCHDOG);
> + ret = _da9063_wdt_reset_timer(da9063);
> if (ret)
> dev_alert(da9063->dev, "Failed to ping the watchdog (err =
> %d)\n",
> ret);
> --
> 2.17.0
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