RE: [PATCH v5 3/5] 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 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 <redacted>
---
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);
 }

--
2.25.1