Re: [PATCH] mmc: sdhci-pxav3: use managed clock enablement

[Adrian Hunter <adrian.hunter@intel.com>]

On 01/09/2026 03:42, Rosen Penev wrote:
> Replace devm_clk_get() plus clk_prepare_enable() with the managed
> variants devm_clk_get_enabled() and devm_clk_get_optional_enabled().
> The core clock becomes optional, which removes the IS_ERR() guards
> in runtime suspend/resume and lets devms unwind the clocks, so the
> manual clk_disable_unprepare() calls in the probe error paths and
> remove are dropped.
> 
> clk_prepare_enable() and friends are NULL safe, so no need to check if
> the optional clock is present.
> 
> Also handle failures of clk_prepare_enable() in runtime resume instead
> of ignoring them: a failed enable would leave controller register
> accesses hitting unclocked hardware. Bail out before resuming the host
> and unwind clk_io when enabling clk_core fails. This also drops the
> now unused pltfm_host variable from remove().
> 
> Assisted-by: opencode:big-pickle
> Signed-off-by: Rosen Penev <rosenp@gmail.com>
> ---
>  drivers/mmc/host/sdhci-pxav3.c | 42 +++++++++++++++-------------------
>  1 file changed, 19 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/mmc/host/sdhci-pxav3.c b/drivers/mmc/host/sdhci-pxav3.c
> index d082c4e21aa9..db9dfa92cb57 100644
> --- a/drivers/mmc/host/sdhci-pxav3.c
> +++ b/drivers/mmc/host/sdhci-pxav3.c
> @@ -414,19 +414,18 @@ static int sdhci_pxav3_probe(struct platform_device *pdev)
>  	pltfm_host = sdhci_priv(host);
>  	pxa = sdhci_pltfm_priv(pltfm_host);
>  
> -	pxa->clk_io = devm_clk_get(dev, "io");
> +	pxa->clk_io = devm_clk_get_enabled(dev, "io");
>  	if (IS_ERR(pxa->clk_io))
> -		pxa->clk_io = devm_clk_get(dev, NULL);
> +		pxa->clk_io = devm_clk_get_enabled(dev, NULL);

Sashiko has a point about getting the wrong clock:

	https://sashiko.dev/#/patchset/20260901004243.50052-1-rosenp%40gmail.com?part=1

>  	if (IS_ERR(pxa->clk_io)) {
>  		dev_err(dev, "failed to get io clock\n");
>  		return PTR_ERR(pxa->clk_io);
>  	}
>  	pltfm_host->clk = pxa->clk_io;
> -	clk_prepare_enable(pxa->clk_io);
>  
> -	pxa->clk_core = devm_clk_get(dev, "core");
> -	if (!IS_ERR(pxa->clk_core))
> -		clk_prepare_enable(pxa->clk_core);
> +	pxa->clk_core = devm_clk_get_optional_enabled(dev, "core");
> +	if (IS_ERR(pxa->clk_core))
> +		return PTR_ERR(pxa->clk_core);
>  
>  	host->mmc->caps |= MMC_CAP_NEED_RSP_BUSY;
>  	/* enable 1/8V DDR capable */
> @@ -435,17 +434,17 @@ static int sdhci_pxav3_probe(struct platform_device *pdev)
>  	if (of_device_is_compatible(np, "marvell,armada-380-sdhci")) {
>  		ret = armada_38x_quirks(pdev, host);
>  		if (ret < 0)
> -			goto err_mbus_win;
> +			return ret;
>  		ret = mv_conf_mbus_windows(pdev, mv_mbus_dram_info());
>  		if (ret < 0)
> -			goto err_mbus_win;
> +			return ret;
>  	}
>  
>  	match = of_match_device(of_match_ptr(sdhci_pxav3_of_match), &pdev->dev);
>  	if (match) {
>  		ret = mmc_of_parse(host->mmc);
>  		if (ret)
> -			goto err_of_parse;
> +			return ret;
>  		sdhci_get_of_property(pdev);
>  		pdata = pxav3_get_mmc_pdata(dev);
>  		pdev->dev.platform_data = pdata;
> @@ -500,27 +499,18 @@ static int sdhci_pxav3_probe(struct platform_device *pdev)
>  err_add_host:
>  	pm_runtime_disable(&pdev->dev);
>  	pm_runtime_put_noidle(&pdev->dev);
> -err_of_parse:
> -err_mbus_win:
> -	clk_disable_unprepare(pxa->clk_io);
> -	clk_disable_unprepare(pxa->clk_core);
>  	return ret;
>  }
>  
>  static void sdhci_pxav3_remove(struct platform_device *pdev)
>  {
>  	struct sdhci_host *host = platform_get_drvdata(pdev);
> -	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> -	struct sdhci_pxa *pxa = sdhci_pltfm_priv(pltfm_host);
>  
>  	pm_runtime_get_sync(&pdev->dev);
>  	pm_runtime_disable(&pdev->dev);
>  	pm_runtime_put_noidle(&pdev->dev);
>  
>  	sdhci_remove_host(host, 1);
> -
> -	clk_disable_unprepare(pxa->clk_io);
> -	clk_disable_unprepare(pxa->clk_core);
>  }
>  
>  static int sdhci_pxav3_suspend(struct device *dev)
> @@ -561,8 +551,7 @@ static int sdhci_pxav3_runtime_suspend(struct device *dev)
>  		mmc_retune_needed(host->mmc);
>  
>  	clk_disable_unprepare(pxa->clk_io);
> -	if (!IS_ERR(pxa->clk_core))
> -		clk_disable_unprepare(pxa->clk_core);
> +	clk_disable_unprepare(pxa->clk_core);
>  
>  	return 0;
>  }
> @@ -572,10 +561,17 @@ static int sdhci_pxav3_runtime_resume(struct device *dev)
>  	struct sdhci_host *host = dev_get_drvdata(dev);
>  	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>  	struct sdhci_pxa *pxa = sdhci_pltfm_priv(pltfm_host);
> +	int ret;
>  
> -	clk_prepare_enable(pxa->clk_io);
> -	if (!IS_ERR(pxa->clk_core))
> -		clk_prepare_enable(pxa->clk_core);
> +	ret = clk_prepare_enable(pxa->clk_io);
> +	if (ret)
> +		return ret;
> +
> +	ret = clk_prepare_enable(pxa->clk_core);
> +	if (ret) {
> +		clk_disable_unprepare(pxa->clk_io);
> +		return ret;
> +	}
>  
>  	sdhci_runtime_resume_host(host, 0);
>  	return 0;