2021-11-30 13:43:05

by Andrej Picej

[permalink] [raw]
Subject: [PATCH v2 2/4] watchdog: da9062: reset board on watchdog timeout

Implement a method to change watchdog timeout configuration based on DT
binding ("dlg,wdt-sd"). There is a possibility to change the bahaviour
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 da9062 multi function device.

Signed-off-by: Andrej Picej <[email protected]>
---
drivers/watchdog/da9062_wdt.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/drivers/watchdog/da9062_wdt.c b/drivers/watchdog/da9062_wdt.c
index f02cbd530538..e342e9e50cb1 100644
--- a/drivers/watchdog/da9062_wdt.c
+++ b/drivers/watchdog/da9062_wdt.c
@@ -85,8 +85,33 @@ static int da9062_wdt_start(struct watchdog_device *wdd)
{
struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
unsigned int selector;
+ unsigned int mask;
+ u32 val;
int ret;

+ /* 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(wdd->parent, "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(wdt->hw->dev, "failed to set wdt reset mode: %d\n",
+ ret);
+ }
+
selector = da9062_wdt_timeout_to_sel(wdt->wdtdev.timeout);
ret = da9062_wdt_update_timeout_register(wdt, selector);
if (ret)
--
2.25.1



2021-11-30 13:54:07

by Andrej Picej

[permalink] [raw]
Subject: Re: [PATCH v2 2/4] watchdog: da9062: reset board on watchdog timeout



On 30. 11. 21 14:42, 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 bahaviour
> 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 da9062 multi function device.
>
> Signed-off-by: Andrej Picej <[email protected]>
> ---
> drivers/watchdog/da9062_wdt.c | 25 +++++++++++++++++++++++++
> 1 file changed, 25 insertions(+)
>
> diff --git a/drivers/watchdog/da9062_wdt.c b/drivers/watchdog/da9062_wdt.c
> index f02cbd530538..e342e9e50cb1 100644
> --- a/drivers/watchdog/da9062_wdt.c
> +++ b/drivers/watchdog/da9062_wdt.c
> @@ -85,8 +85,33 @@ static int da9062_wdt_start(struct watchdog_device *wdd)
> {
> struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
> unsigned int selector;
> + unsigned int mask;
> + u32 val;
> int ret;
>
> + /* 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(wdd->parent, "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(wdt->hw->dev, "failed to set wdt reset mode: %d\n",
> + ret);
> + }
> +
> selector = da9062_wdt_timeout_to_sel(wdt->wdtdev.timeout);
> ret = da9062_wdt_update_timeout_register(wdt, selector);
> if (ret)
>

Changes in v2:
- don't force the "reset" for all da9062-watchdog users, instead add DT
binding where the behavior can be selected