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Subject: Re: [PATCH] ASoC: stm32: spdifrx: Delete unnecessary check in the
 probe function
To:     Mark Brown <broonie@kernel.org>
Cc:     olivier.moysan@foss.st.com, arnaud.pouliquen@foss.st.com,
        lgirdwood@gmail.com, perex@perex.cz, tiwai@suse.com,
        linux-stm32@st-md-mailman.stormreply.com,
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References: <20210811115523.17232-1-tangbin@cmss.chinamobile.com>
 <20210811115846.GC4167@sirena.org.uk>
 <7ddb13ee-2ca6-bf8d-2a83-9896d29176c5@cmss.chinamobile.com>
 <20210811121955.GD4167@sirena.org.uk>
From:   tangbin <tangbin@cmss.chinamobile.com>
Message-ID: <d0fa7aa5-b64b-7d4a-a80d-ec2f6dec5712@cmss.chinamobile.com>
Date:   Wed, 11 Aug 2021 20:28:23 +0800
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Hi Mark:

On 2021/8/11 20:19, Mark Brown wrote:
> On Wed, Aug 11, 2021 at 08:09:00PM +0800, tangbin wrote:
>> On 2021/8/11 19:58, Mark Brown wrote:
>>> On Wed, Aug 11, 2021 at 07:55:23PM +0800, Tang Bin wrote:
>>>> The function stm32_spdifrx_parse_of() is only called by the function
>>>> stm32_spdifrx_probe(), and the probe function is only called with
>>>> an openfirmware platform device. Therefore there is no need to check
>>>> the device_node in probe function.
>>> What is the benefit of not doing the check?  It seems like reasonable
>>> defensive programming.
>> I think it's unnecessary, because we all know than the probe function is
>> only trigger if
>> the device and the driver matches, and the trigger mode is just Device Tree.
>> So the device_node
>> must be exist in the probe function if it works. That's the reason why I
>> think it's redundant.
> I see why it is redundant, I don't see what problem this redudnancy
> causes.

Maybe not, just be redundant. If you think that's ok, just drop this patch.

I'm sorry to trouble you.

Thanks

Tang Bin