Re: [PATCH 2/7] iio: adc: rockchip_saradc: Make use of devm_clk_get_enabled

[Jonathan Cameron <jic23@kernel.org>]

On Wed, 17 May 2023 04:30:46 +0530
Shreeya Patel <shreeya.patel@collabora.com> wrote:

> Use devm_clk_get_enabled() to avoid manually disabling the
> clock.

Please comment on why the enable is now done earlier than before.

> 
> Signed-off-by: Shreeya Patel <shreeya.patel@collabora.com>
> ---
>  drivers/iio/adc/rockchip_saradc.c | 77 +++++--------------------------
>  1 file changed, 11 insertions(+), 66 deletions(-)
> 
> diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c
> index ac6fdf8e673b..05b66eff9a44 100644
> --- a/drivers/iio/adc/rockchip_saradc.c
> +++ b/drivers/iio/adc/rockchip_saradc.c
> @@ -339,20 +339,6 @@ static void rockchip_saradc_reset_controller(struct reset_control *reset)
>  	reset_control_deassert(reset);
>  }
>  
> -static void rockchip_saradc_clk_disable(void *data)
> -{
> -	struct rockchip_saradc *info = data;
> -
> -	clk_disable_unprepare(info->clk);
> -}
> -
> -static void rockchip_saradc_pclk_disable(void *data)
> -{
> -	struct rockchip_saradc *info = data;
> -
> -	clk_disable_unprepare(info->pclk);
> -}
> -
>  static void rockchip_saradc_regulator_disable(void *data)
>  {
>  	struct rockchip_saradc *info = data;
> @@ -486,16 +472,6 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
>  		return ret;
>  	}
>  
> -	info->pclk = devm_clk_get(&pdev->dev, "apb_pclk");
> -	if (IS_ERR(info->pclk))
> -		return dev_err_probe(&pdev->dev, PTR_ERR(info->pclk),
> -				     "failed to get pclk\n");
> -
> -	info->clk = devm_clk_get(&pdev->dev, "saradc");
> -	if (IS_ERR(info->clk))
> -		return dev_err_probe(&pdev->dev, PTR_ERR(info->clk),
> -				     "failed to get adc clock\n");
> -
>  	info->vref = devm_regulator_get(&pdev->dev, "vref");
>  	if (IS_ERR(info->vref))
>  		return dev_err_probe(&pdev->dev, PTR_ERR(info->vref),
> @@ -504,6 +480,16 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
>  	if (info->reset)
>  		rockchip_saradc_reset_controller(info->reset);
>  
> +	info->pclk = devm_clk_get_enabled(&pdev->dev, "apb_pclk");
> +	if (IS_ERR(info->pclk))
> +		return dev_err_probe(&pdev->dev, PTR_ERR(info->pclk),
> +				     "failed to get pclk\n");
> +
> +	info->clk = devm_clk_get_enabled(&pdev->dev, "saradc");
> +	if (IS_ERR(info->clk))
> +		return dev_err_probe(&pdev->dev, PTR_ERR(info->clk),
> +				     "failed to get adc clock\n");
> +
>  	/*
>  	 * Use a default value for the converter clock.
>  	 * This may become user-configurable in the future.
> @@ -533,32 +519,6 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
>  
>  	info->uv_vref = ret;
>  
> -	ret = clk_prepare_enable(info->pclk);
> -	if (ret < 0) {
> -		dev_err(&pdev->dev, "failed to enable pclk\n");
> -		return ret;
> -	}
> -	ret = devm_add_action_or_reset(&pdev->dev,
> -				       rockchip_saradc_pclk_disable, info);
> -	if (ret) {
> -		dev_err(&pdev->dev, "failed to register devm action, %d\n",
> -			ret);
> -		return ret;
> -	}
> -
> -	ret = clk_prepare_enable(info->clk);
> -	if (ret < 0) {
> -		dev_err(&pdev->dev, "failed to enable converter clock\n");
> -		return ret;
> -	}
> -	ret = devm_add_action_or_reset(&pdev->dev,
> -				       rockchip_saradc_clk_disable, info);
> -	if (ret) {
> -		dev_err(&pdev->dev, "failed to register devm action, %d\n",
> -			ret);
> -		return ret;
> -	}
> -
>  	platform_set_drvdata(pdev, indio_dev);
>  
>  	indio_dev->name = dev_name(&pdev->dev);
> @@ -594,8 +554,6 @@ static int rockchip_saradc_suspend(struct device *dev)
>  	struct iio_dev *indio_dev = dev_get_drvdata(dev);
>  	struct rockchip_saradc *info = iio_priv(indio_dev);
>  
> -	clk_disable_unprepare(info->clk);
> -	clk_disable_unprepare(info->pclk);
>  	regulator_disable(info->vref);
>  
>  	return 0;
> @@ -605,21 +563,8 @@ static int rockchip_saradc_resume(struct device *dev)
>  {
>  	struct iio_dev *indio_dev = dev_get_drvdata(dev);
>  	struct rockchip_saradc *info = iio_priv(indio_dev);
> -	int ret;
> -
> -	ret = regulator_enable(info->vref);
> -	if (ret)
> -		return ret;
> -
> -	ret = clk_prepare_enable(info->pclk);
> -	if (ret)
> -		return ret;
> -
> -	ret = clk_prepare_enable(info->clk);
> -	if (ret)
> -		clk_disable_unprepare(info->pclk);
>  
> -	return ret;
> +	return regulator_enable(info->vref);
>  }
>  
>  static DEFINE_SIMPLE_DEV_PM_OPS(rockchip_saradc_pm_ops,