Re: [PATCH v1 3/4] ASoC: Intel: bytcr_rt5640: use devm_clk_get_optional() for mclk

Pierre-Louis Bossart
2021-10-06T16:13:56Z

On 10/6/21 10:04 AM, Andy Shevchenko wrote:
> The devm_clk_get_optional() helper returns NULL when devm_clk_get()
> returns -ENOENT. This makes things slightly cleaner. The added benefit
> is mostly cosmetic.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> sound/soc/intel/boards/bytcr_rt5640.c | 75 ++++++++++++---------------
> 1 file changed, 32 insertions(+), 43 deletions(-)
>
> diff --git a/sound/soc/intel/boards/bytcr_rt5640.c b/sound/soc/intel/boards/bytcr_rt5640.c
> index 0f609a0b3527..2e7d45f0f05d 100644
> --- a/sound/soc/intel/boards/bytcr_rt5640.c
> +++ b/sound/soc/intel/boards/bytcr_rt5640.c
> @@ -269,13 +269,10 @@ static int platform_clock_control(struct snd_soc_dapm_widget *w,
> return -EIO;
>
> if (SND_SOC_DAPM_EVENT_ON(event)) {
> - if (byt_rt5640_quirk & BYT_RT5640_MCLK_EN) {

same comment as for rt5651, I don't see the point of removing the test
on this quirk?

> - ret = clk_prepare_enable(priv->mclk);
> - if (ret < 0) {
> - dev_err(card->dev,
> - "could not configure MCLK state\n");
> - return ret;
> - }
> + ret = clk_prepare_enable(priv->mclk);
> + if (ret < 0) {
> + dev_err(card->dev, "could not configure MCLK state\n");
> + return ret;
> }
> ret = byt_rt5640_prepare_and_enable_pll1(codec_dai, 48000);
> } else {
> @@ -287,10 +284,8 @@ static int platform_clock_control(struct snd_soc_dapm_widget *w,
> ret = snd_soc_dai_set_sysclk(codec_dai, RT5640_SCLK_S_RCCLK,
> 48000 * 512,
> SND_SOC_CLOCK_IN);
> - if (!ret) {
> - if (byt_rt5640_quirk & BYT_RT5640_MCLK_EN)
> - clk_disable_unprepare(priv->mclk);
> - }
> + if (!ret)
> + clk_disable_unprepare(priv->mclk);
> }
>
> if (ret < 0) {
> @@ -1217,30 +1212,25 @@ static int byt_rt5640_init(struct snd_soc_pcm_runtime *runtime)
> return ret;
> }
>
> - if (byt_rt5640_quirk & BYT_RT5640_MCLK_EN) {
> - /*
> - * The firmware might enable the clock at
> - * boot (this information may or may not
> - * be reflected in the enable clock register).
> - * To change the rate we must disable the clock
> - * first to cover these cases. Due to common
> - * clock framework restrictions that do not allow
> - * to disable a clock that has not been enabled,
> - * we need to enable the clock first.
> - */
> - ret = clk_prepare_enable(priv->mclk);
> - if (!ret)
> - clk_disable_unprepare(priv->mclk);
> -
> - if (byt_rt5640_quirk & BYT_RT5640_MCLK_25MHZ)
> - ret = clk_set_rate(priv->mclk, 25000000);
> - else
> - ret = clk_set_rate(priv->mclk, 19200000);
> + /*
> + * The firmware might enable the clock at boot (this information
> + * may or may not be reflected in the enable clock register).
> + * To change the rate we must disable the clock first to cover
> + * these cases. Due to common clock framework restrictions that
> + * do not allow to disable a clock that has not been enabled,
> + * we need to enable the clock first.
> + */
> + ret = clk_prepare_enable(priv->mclk);
> + if (!ret)
> + clk_disable_unprepare(priv->mclk);
>
> - if (ret) {
> - dev_err(card->dev, "unable to set MCLK rate\n");
> - return ret;
> - }
> + if (byt_rt5640_quirk & BYT_RT5640_MCLK_25MHZ)
> + ret = clk_set_rate(priv->mclk, 25000000);
> + else
> + ret = clk_set_rate(priv->mclk, 19200000);
> + if (ret) {
> + dev_err(card->dev, "unable to set MCLK rate\n");
> + return ret;
> }
>
> if (BYT_RT5640_JDSRC(byt_rt5640_quirk)) {
> @@ -1653,7 +1643,7 @@ static int snd_byt_rt5640_mc_probe(struct platform_device *pdev)
> byt_rt5640_dais[dai_index].cpus->dai_name = "ssp0-port";
>
> if (byt_rt5640_quirk & BYT_RT5640_MCLK_EN) {
> - priv->mclk = devm_clk_get(dev, "pmc_plt_clk_3");
> + priv->mclk = devm_clk_get_optional(dev, "pmc_plt_clk_3");
> if (IS_ERR(priv->mclk)) {
> ret_val = PTR_ERR(priv->mclk);
>
> @@ -1661,15 +1651,14 @@ static int snd_byt_rt5640_mc_probe(struct platform_device *pdev)
> "Failed to get MCLK from pmc_plt_clk_3: %d\n",
> ret_val);
>
> - /*
> - * Fall back to bit clock usage for -ENOENT (clock not
> - * available likely due to missing dependencies), bail
> - * for all other errors, including -EPROBE_DEFER
> - */
> - if (ret_val != -ENOENT)
> - goto err;
> - byt_rt5640_quirk &= ~BYT_RT5640_MCLK_EN;
> + goto err;
> }
> + /*
> + * Fall back to bit clock usage when clock is not
> + * available likely due to missing dependencies.
> + */
> + if (!priv->mclk)
> + byt_rt5640_quirk &= ~BYT_RT5640_MCLK_EN;
> }
>
> if (byt_rt5640_quirk & BYT_RT5640_NO_SPEAKERS) {
>