Re: [PATCH v2 5/5] ASoC: da7219: properly get clk from the provider - Pierre-Louis Bossart

From: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
To: Jerome Brunet <jbrunet@baylibre.com>, Mark Brown <broonie@kernel.org>
Cc: Stephen Boyd <sboyd@kernel.org>,
	alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 5/5] ASoC: da7219: properly get clk from the provider
Date: Mon, 26 Apr 2021 13:10:36 -0500	[thread overview]
Message-ID: <69eaa840-ed77-fc01-2925-7e5e9998e80f@linux.intel.com> (raw)
In-Reply-To: <20210421120512.413057-6-jbrunet@baylibre.com>

On 4/21/21 7:05 AM, Jerome Brunet wrote:
> Instead of using the clk embedded in the clk_hw (which is meant to go
> away), a clock provider which need to interact with its own clock should
> request clk reference through the clock provider API.
> 
> Reviewed-by: Stephen Boyd <sboyd@kernel.org>
> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>

This patch seems to introduce a regression in our modprobe/rmmod tests

https://github.com/thesofproject/linux/pull/2870

RMMOD	snd_soc_da7219
rmmod: ERROR: Module snd_soc_da7219 is in use

Reverting this patch restores the ability to remove the module.

Wondering if devm_ increases a module/device refcount somehow?

> ---
>   sound/soc/codecs/da7219.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/sound/soc/codecs/da7219.c b/sound/soc/codecs/da7219.c
> index 13009d08b09a..bd3c523a8617 100644
> --- a/sound/soc/codecs/da7219.c
> +++ b/sound/soc/codecs/da7219.c
> @@ -2181,7 +2181,10 @@ static int da7219_register_dai_clks(struct snd_soc_component *component)
>   				 ret);
>   			goto err;
>   		}
> -		da7219->dai_clks[i] = dai_clk_hw->clk;
> +
> +		da7219->dai_clks[i] = devm_clk_hw_get_clk(dev, dai_clk_hw, NULL);
> +		if (IS_ERR(da7219->dai_clks[i]))
> +			return PTR_ERR(da7219->dai_clks[i]);
>   
>   		/* For DT setup onecell data, otherwise create lookup */
>   		if (np) {
> 