Re: [v2,1/2] watchdog: mtk: add disable_wdt_extrst support

From: Guenter Roeck
Date: Fri Sep 03 2021 - 10:05:10 EST


On 9/2/21 11:16 PM, Fengquan Chen wrote:
In some cases, we may need watchdog just to trigger an
internal soc reset without sending any output signal.

Provide a disable_wdt_extrst parameter for configuration.
We can disable or enable it just by configuring dts.

Signed-off-by: fengquan.chen <fengquan.chen@xxxxxxxxxxxx>

Nit: You should set up git such that it uses "Fengquan Chen", not
"fengquan.chen".

Other than that, for my reference,

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

We'll have to wait for dt property approval before we can apply the patch.

Thanks,
Guenter

---
drivers/watchdog/mtk_wdt.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c
index 97ca993bd009..276b6cb7d225 100644
--- a/drivers/watchdog/mtk_wdt.c
+++ b/drivers/watchdog/mtk_wdt.c
@@ -63,6 +63,7 @@ struct mtk_wdt_dev {
void __iomem *wdt_base;
spinlock_t lock; /* protects WDT_SWSYSRST reg */
struct reset_controller_dev rcdev;
+ bool disable_wdt_extrst;
};
struct mtk_wdt_data {
@@ -240,6 +241,8 @@ static int mtk_wdt_start(struct watchdog_device *wdt_dev)
reg = ioread32(wdt_base + WDT_MODE);
reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN);
+ if (mtk_wdt->disable_wdt_extrst)
+ reg &= ~WDT_MODE_EXRST_EN;
reg |= (WDT_MODE_EN | WDT_MODE_KEY);
iowrite32(reg, wdt_base + WDT_MODE);
@@ -309,6 +312,10 @@ static int mtk_wdt_probe(struct platform_device *pdev)
if (err)
return err;
}
+
+ mtk_wdt->disable_wdt_extrst =
+ of_property_read_bool(dev->of_node, "mediatek,disable-extrst");
+
return 0;
}