Re: [PATCH v5 3/5] watchdog: da9062: reset board on watchdog timeout

Guenter Roeck
2022-09-25T17:16:24Z

On Mon, Dec 06, 2021 at 07:47:30AM +0100, Andrej Picej wrote:
> Implement a method to change watchdog timeout configuration based on DT
> binding ("dlg,wdt-sd"). There is a possibility to change the behaviour
> of watchdog reset. Setting WATCHDOG_SD bit enables SHUTDOWN mode, and
> clearing it enables POWERDOWN mode on watchdog timeout.
>
> If no DT binding is specified the WATCHDOG_SD bit stays in default
> configuration, not breaking behaviour of devices which might depend on
> default fuse configuration.
>
> Note: This patch requires that the config register CONFIG_I is
> configured as writable in the da9061/2 multi function device.
>
> Signed-off-by: Andrej Picej <andrej.picej@norik.com>
> Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>

Acked-by: Guenter Roeck <linux@roeck-us.net>

Depends on changes to be made in mfd driver.

Guenter

> ---
> Changes in v5:
> - fix spelling mistake in commit message
>
> Changes in v4:
> - move the code to probe function
>
> Changes in v3:
> - no changes
>
> Changes in v2:
> - don't force the "reset" for all da9062-watchdog users, instead add DT
> binding where the behavior can be selected
> ---
> drivers/watchdog/da9062_wdt.c | 27 +++++++++++++++++++++++++++
> 1 file changed, 27 insertions(+)
>
> diff --git a/drivers/watchdog/da9062_wdt.c b/drivers/watchdog/da9062_wdt.c
> index f02cbd530538..bd85f84b0fd4 100644
> --- a/drivers/watchdog/da9062_wdt.c
> +++ b/drivers/watchdog/da9062_wdt.c
> @@ -195,8 +195,11 @@ static int da9062_wdt_probe(struct platform_device *pdev)
> {
> struct device *dev = &pdev->dev;
> unsigned int timeout;
> + unsigned int mask;
> struct da9062 *chip;
> struct da9062_watchdog *wdt;
> + int ret;
> + u32 val;
>
> chip = dev_get_drvdata(dev->parent);
> if (!chip)
> @@ -236,6 +239,30 @@ static int da9062_wdt_probe(struct platform_device *pdev)
> set_bit(WDOG_HW_RUNNING, &wdt->wdtdev.status);
> }
>
> + /*
> + * Configure what happens on watchdog timeout. Can be specified with
> + * "dlg,wdt-sd" dt-binding (0 -> POWERDOWN, 1 -> SHUTDOWN).
> + * If "dlg,wdt-sd" dt-binding is NOT set use the default.
> + */
> + ret = device_property_read_u32(dev, "dlg,wdt-sd", &val);
> + if (!ret) {
> + if (val)
> + /* Use da9062's SHUTDOWN mode */
> + mask = DA9062AA_WATCHDOG_SD_MASK;
> + else
> + /* Use da9062's POWERDOWN mode. */
> + mask = 0x0;
> +
> + ret = regmap_update_bits(wdt->hw->regmap,
> + DA9062AA_CONFIG_I,
> + DA9062AA_WATCHDOG_SD_MASK,
> + mask);
> +
> + if (ret)
> + dev_err(dev, "failed to set wdt reset mode: %d\n",
> + ret);
> + }
> +
> return devm_watchdog_register_device(dev, &wdt->wdtdev);
> }
>