From: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Support an already running watchdog by checking its enable bit and set
up the status accordingly before registering the device.
Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
---
Change since v1:
* removed custom code to handle RPM refcnt. The watchdog core does it
already.
Tested again on a Renesas Salvator-XS (R-Car M3N) with and without the
'open_timeout' command line parameter.
After all these discussions, the patch became quite simple again :/
Still, thanks for all the discussions to make sure we didn't overlook
clock handling.
drivers/watchdog/renesas_wdt.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/watchdog/renesas_wdt.c b/drivers/watchdog/renesas_wdt.c
index 00662a8e039c..47fce4de0110 100644
--- a/drivers/watchdog/renesas_wdt.c
+++ b/drivers/watchdog/renesas_wdt.c
@@ -194,6 +194,7 @@ static int rwdt_probe(struct platform_device *pdev)
struct clk *clk;
unsigned long clks_per_sec;
int ret, i;
+ u8 csra;
if (rwdt_blacklisted(dev))
return -ENODEV;
@@ -213,8 +214,8 @@ static int rwdt_probe(struct platform_device *pdev)
pm_runtime_enable(dev);
pm_runtime_get_sync(dev);
priv->clk_rate = clk_get_rate(clk);
- priv->wdev.bootstatus = (readb_relaxed(priv->base + RWTCSRA) &
- RWTCSRA_WOVF) ? WDIOF_CARDRESET : 0;
+ csra = readb_relaxed(priv->base + RWTCSRA);
+ priv->wdev.bootstatus = csra & RWTCSRA_WOVF ? WDIOF_CARDRESET : 0;
pm_runtime_put(dev);
if (!priv->clk_rate) {
@@ -252,6 +253,13 @@ static int rwdt_probe(struct platform_device *pdev)
/* This overrides the default timeout only if DT configuration was found */
watchdog_init_timeout(&priv->wdev, 0, dev);
+ /* Check if FW enabled the watchdog */
+ if (csra & RWTCSRA_TME) {
+ /* Ensure properly initialized dividers */
+ rwdt_start(&priv->wdev);
+ set_bit(WDOG_HW_RUNNING, &priv->wdev.status);
+ }
+
ret = watchdog_register_device(&priv->wdev);
if (ret < 0)
goto out_pm_disable;
--
2.20.1
