linux-kernel - Re: [PATCH 2/3] watchdog: xilinx_wwdt: Add Versal window watchdog support

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Message-ID: <e92d1547-428c-0232-d769-9c342e3a0c88@linaro.org>
Date:   Mon, 3 Oct 2022 09:00:11 +0200
From:   Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
To:     Guenter Roeck <linux@...ck-us.net>,
        Srinivas Neeli <srinivas.neeli@....com>,
        wim@...ux-watchdog.org, shubhrajyoti.datta@....com,
        michal.simek@....com, robh+dt@...nel.org,
        krzysztof.kozlowski+dt@...aro.org
Cc:     linux-kernel@...r.kernel.org, linux-watchdog@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, devicetree@...r.kernel.org,
        git@....com
Subject: Re: [PATCH 2/3] watchdog: xilinx_wwdt: Add Versal window watchdog
 support

On 02/10/2022 18:29, Guenter Roeck wrote:
> On 9/30/22 03:35, Krzysztof Kozlowski wrote:
>> On 27/09/2022 13:02, Srinivas Neeli wrote:
>>> +
>>> +static void xwwdt_clk_disable_unprepare(void *data)
>>> +{
>>> +	clk_disable_unprepare(data);
>>
>> If watchdog is stopped and then device unbound, don't you have double
>> disable? IOW, where is matching clk_enable?
>>
> 
> After looking into the entire driver code, I see the problem:
> clk_disable() is called in the stop function. That is wrong;
> if the clock is disabled in the stop function, it needs to be

Yep. clk_disable and clk_enable are always paired. In probe they are
pared with remove() or reset-action. This one is in stop(), so it does
not have its pair.

Best regards,
Krzysztof