Re: [PATCH 2/3] mmc: sdhci-esdhc-imx: obtain the 'per' clock rate after its enablement

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

On 8/07/24 15:10, Ciprian Costea wrote:
> The I.MX SDHCI driver assumes that the frequency of the 'per' clock
> can be obtained even on disabled clocks, which is not always the case.
> 
> According to 'clk_get_rate' documentation, it is only valid
> once the clock source has been enabled.

The kerneldoc comment for clk_get_rate() says

	Can be called regardless of the clock enabledness

which sounds like the opposite.  Please clarify.

> 
> Signed-off-by: Ciprian Costea <ciprianmarian.costea@oss.nxp.com>
> ---
>  drivers/mmc/host/sdhci-esdhc-imx.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
> index 21d984a77be8..8f0bc6dca2b0 100644
> --- a/drivers/mmc/host/sdhci-esdhc-imx.c
> +++ b/drivers/mmc/host/sdhci-esdhc-imx.c
> @@ -1709,7 +1709,6 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev)
>  	}
>  
>  	pltfm_host->clk = imx_data->clk_per;
> -	pltfm_host->clock = clk_get_rate(pltfm_host->clk);
>  	err = clk_prepare_enable(imx_data->clk_per);
>  	if (err)
>  		goto free_sdhci;
> @@ -1720,6 +1719,13 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev)
>  	if (err)
>  		goto disable_ipg_clk;
>  
> +	pltfm_host->clock = clk_get_rate(pltfm_host->clk);
> +	if (!pltfm_host->clock) {
> +		dev_err(mmc_dev(host->mmc), "could not get clk rate\n");
> +		err = -EINVAL;
> +		goto disable_ahb_clk;
> +	}
> +
>  	imx_data->pinctrl = devm_pinctrl_get(&pdev->dev);
>  	if (IS_ERR(imx_data->pinctrl))
>  		dev_warn(mmc_dev(host->mmc), "could not get pinctrl\n");