Hi Marco, On 09 May 2018 13:33, Marco Felsch wrote: > To: wim@xxxxxxxxxxxxxxxxxx; linux@xxxxxxxxxxxx > Subject: [PATCH v2] watchdog: da9063: Fix setting/changing timeout > > The DA9063 watchdog always resets the system when it changes the timeout > value after the bootloader (e.g. Barebox) has it already set. > > 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 <p.zabel@xxxxxxxxxxxxxx> previous > patch but doesn't wait 150us because the DA9063 doesn't need this delay. https://www.dialog-semiconductor.com/products/DA9063 Yes, according to the Dialog datasheet DA9063_2v1, there is no 150us minimum assert time limit. But ... that doesn't seem correct to me, because the DA9062 driver and DA9062 datasheet both show a minimum assertion time, like you said. https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/tree/drivers/watchdog/da9062_wdt.c?h=v4.17-rc3#n67 So let me check with the hardware engineers. Regards, Steve > > Fixes: 5e9c16e37608 ("watchdog: Add DA9063 PMIC watchdog driver.") > Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx> > --- > drivers/watchdog/da9063_wdt.c | 33 > +++++++++++++++++++++++++++++++-- > 1 file changed, 31 insertions(+), 2 deletions(-) > > diff --git a/drivers/watchdog/da9063_wdt.c > b/drivers/watchdog/da9063_wdt.c > index b17ac1bb1f28..bca247d44737 100644 > --- a/drivers/watchdog/da9063_wdt.c > +++ b/drivers/watchdog/da9063_wdt.c > @@ -45,8 +45,38 @@ 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 trigger a reboot if a timeout value is already > + * programmed. Because the timeout value combines two functions in > + * one: indicating the counter limit and starting the watchdog. To be > + * able to set the watchdog a second time (first time was done by the > + * bootloader) disable the watchdog clear the counter value manually and > + * set the new timeout value. > + */ > + 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"); > + > + 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 +115,7 @@ 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 -- To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
