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Sender: Guenter Roeck <groeck7@gmail.com>
Subject: Re: [v2,1/2] watchdog: mtk: add disable_wdt_extrst support
To:     Fengquan Chen <Fengquan.Chen@mediatek.com>,
        Wim Van Sebroeck <wim@linux-watchdog.org>,
        Rob Herring <robh+dt@kernel.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org
Cc:     tinghan.shen@mediatek.com, randy.wu@mediatek.com,
        rex-bc.chen@mediatek.com, christine.zhu@mediatek.com,
        joe.yang@mediatek.com, zhishuang.zhang@mediatek.com
References: <20210903061623.10715-1-Fengquan.Chen@mediatek.com>
 <20210903061623.10715-2-Fengquan.Chen@mediatek.com>
From:   Guenter Roeck <linux@roeck-us.net>
Message-ID: <65cc931f-ba49-19b5-ce25-c49f7b984cec@roeck-us.net>
Date:   Fri, 3 Sep 2021 07:05:01 -0700
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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@mediatek.com>

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@roeck-us.net>

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;
>   }
>   
>