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Subject: Re: [PATCH v2][next] ASoC: ti: davinci-mcasp: Fix fall-through
 warning for Clang
To:     Joe Perches <joe@perches.com>,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.com>
Cc:     alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org,
        linux-hardening@vger.kernel.org
References: <20210604072714.GA244640@embeddedor>
 <a0452dc7da2c46e3e764bdd5fd9b94dc96d96912.camel@perches.com>
From:   =?UTF-8?Q?P=c3=a9ter_Ujfalusi?= <peter.ujfalusi@gmail.com>
Message-ID: <4c217782-21e5-b408-0fb9-f0a2c5b31591@gmail.com>
Date:   Fri, 4 Jun 2021 11:44:19 +0300
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On 04/06/2021 10:53, Joe Perches wrote:
> On Fri, 2021-06-04 at 02:27 -0500, Gustavo A. R. Silva wrote:
>> In preparation to enable -Wimplicit-fallthrough for Clang, fix a warning
>> by explicitly adding a fallthrough; statement.
>>
>> Link: https://github.com/KSPP/linux/issues/115
>> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
>> ---
>> Changes in v2:
>>  - Use fallthrough; instead of break;
>>  - Update changelog text.
>>  Link: https://lore.kernel.org/linux-hardening/25941c37-6e38-88ae-3afe-4f5af44380d3@gmail.com/
> []
>> diff --git a/sound/soc/ti/davinci-mcasp.c b/sound/soc/ti/davinci-mcasp.c
> []
>> @@ -2317,6 +2317,7 @@ static int davinci_mcasp_probe(struct platform_device *pdev)
>>  		break;
>>  	default:
>>  		dev_err(&pdev->dev, "No DMA controller found (%d)\n", ret);
>> +		fallthrough;
>>  	case -EPROBE_DEFER:
>>  		goto err;
>>  	}
> 
> While this is OK, perhaps the below would be clearer and a more common style
> as it doesn't intermix default: with logging output and a case label.

True, this looks even better.

Acked-by: Peter Ujfalusi <peter.ujflausi@gmail.com>

> ---
>  sound/soc/ti/davinci-mcasp.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/sound/soc/ti/davinci-mcasp.c b/sound/soc/ti/davinci-mcasp.c
> index b94220306d1a8..1059a696ff90e 100644
> --- a/sound/soc/ti/davinci-mcasp.c
> +++ b/sound/soc/ti/davinci-mcasp.c
> @@ -2305,6 +2305,9 @@ static int davinci_mcasp_probe(struct platform_device *pdev)
>  		goto err;
>  
>  	ret = davinci_mcasp_get_dma_type(mcasp);
> +	if (ret == -EPROBE_DEFER)
> +		goto err;
> +
>  	switch (ret) {
>  	case PCM_EDMA:
>  		ret = edma_pcm_platform_register(&pdev->dev);
> @@ -2317,7 +2320,6 @@ static int davinci_mcasp_probe(struct platform_device *pdev)
>  		break;
>  	default:
>  		dev_err(&pdev->dev, "No DMA controller found (%d)\n", ret);
> -	case -EPROBE_DEFER:
>  		goto err;
>  	}
>  
> 

-- 
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