Re: [PATCH] watchdog: msc313e: Check if the WDT was running at boot

From: Guenter Roeck
Date: Tue Dec 28 2021 - 11:06:19 EST


On 12/27/21 11:34 PM, Daniel Palmer wrote:
Check if the WDT was running at boot and set the running
flag if it was. This prevents the system from getting
rebooted if the userland daemon doesn't take over soon enough
or there isn't a userland daemon at all.

Signed-off-by: Daniel Palmer <daniel@xxxxxxxx>

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

---
drivers/watchdog/msc313e_wdt.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/watchdog/msc313e_wdt.c b/drivers/watchdog/msc313e_wdt.c
index 0d497aa0fb7d..90171431fc59 100644
--- a/drivers/watchdog/msc313e_wdt.c
+++ b/drivers/watchdog/msc313e_wdt.c
@@ -120,6 +120,10 @@ static int msc313e_wdt_probe(struct platform_device *pdev)
priv->wdev.max_timeout = U32_MAX / clk_get_rate(priv->clk);
priv->wdev.timeout = MSC313E_WDT_DEFAULT_TIMEOUT;
+ /* If the period is non-zero the WDT is running */
+ if (readw(priv->base + REG_WDT_MAX_PRD_L) | (readw(priv->base + REG_WDT_MAX_PRD_H) << 16))
+ set_bit(WDOG_HW_RUNNING, &priv->wdev.status);
+
watchdog_set_drvdata(&priv->wdev, priv);
watchdog_init_timeout(&priv->wdev, timeout, dev);