Re: [PATCH v3 1/2] iio: adc: vf610_adc: use devm_* and dev_err_probe() to simple code

[Christophe JAILLET <christophe.jaillet@wanadoo.fr>]

Le 07/11/2024 à 20:18, Frank Li a écrit :
> Use devm_* and dev_err_probe() simplify probe function and remove
> vf610_adc_remove(). Change type of 'vref_uv' to int because
> regulator_get_voltage() return type is int.
> 
> Reviewed-by: Haibo Chen <haibo.chen-3arQi8VN3Tc@public.gmane.org>
> Signed-off-by: Frank Li <Frank.Li-3arQi8VN3Tc@public.gmane.org>
> ---
> Change from v2 to v3
> - change vref_uv to int from u32 to fix below warning
> | Reported-by: kernel test robot <lkp-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202411070633.NIrO7Ert-lkp-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org/
> smatch warnings:
> drivers/iio/adc/vf610_adc.c:857 vf610_adc_probe() warn: unsigned 'info->vref_uv' is never less than zero.
> 
> vim +857 drivers/iio/adc/vf610_adc.c
> 
> Change from v1 to v2
> - add Haibo's review tag
> ---
>   drivers/iio/adc/vf610_adc.c | 79 ++++++++++---------------------------
>   1 file changed, 20 insertions(+), 59 deletions(-)
> 
> diff --git a/drivers/iio/adc/vf610_adc.c b/drivers/iio/adc/vf610_adc.c
> index 4d83c12975c53..a6a0ada8a102f 100644
> --- a/drivers/iio/adc/vf610_adc.c
> +++ b/drivers/iio/adc/vf610_adc.c
> @@ -160,7 +160,7 @@ struct vf610_adc {
>   	/* lock to protect against multiple access to the device */
>   	struct mutex lock;
>   
> -	u32 vref_uv;
> +	int vref_uv;
>   	u32 value;
>   	struct regulator *vref;
>   
> @@ -823,10 +823,8 @@ static int vf610_adc_probe(struct platform_device *pdev)
>   	int ret;
>   
>   	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct vf610_adc));
> -	if (!indio_dev) {
> -		dev_err(&pdev->dev, "Failed allocating iio device\n");
> -		return -ENOMEM;
> -	}
> +	if (!indio_dev)
> +		return dev_err_probe(&pdev->dev, -ENOMEM, "Failed allocating iio device\n");
>   
>   	info = iio_priv(indio_dev);
>   	info->dev = &pdev->dev;
> @@ -842,27 +840,22 @@ static int vf610_adc_probe(struct platform_device *pdev)
>   	ret = devm_request_irq(info->dev, irq,
>   				vf610_adc_isr, 0,
>   				dev_name(&pdev->dev), indio_dev);
> -	if (ret < 0) {
> -		dev_err(&pdev->dev, "failed requesting irq, irq = %d\n", irq);
> -		return ret;
> -	}
> +	if (ret < 0)
> +		dev_err_probe(&pdev->dev, ret, "failed requesting irq, irq = %d\n", irq);

missing return?

>   
> -	info->clk = devm_clk_get(&pdev->dev, "adc");
> -	if (IS_ERR(info->clk)) {
> -		dev_err(&pdev->dev, "failed getting clock, err = %ld\n",
> -						PTR_ERR(info->clk));
> -		return PTR_ERR(info->clk);
> -	}
> +	info->clk = devm_clk_get_enabled(&pdev->dev, "adc");
> +	if (IS_ERR(info->clk))
> +		return dev_err_probe(&pdev->dev, PTR_ERR(info->clk),
> +				     "failed getting clock, err = %ld\n",
> +				     PTR_ERR(info->clk));

No need to add an extra PTR_ERR(info->clk)

>   
>   	info->vref = devm_regulator_get(&pdev->dev, "vref");

With the change to devm_regulator_get_enable_read_voltage(), is it still 
needed?

CJ

>   	if (IS_ERR(info->vref))
>   		return PTR_ERR(info->vref);
>   
> -	ret = regulator_enable(info->vref);
> -	if (ret)
> -		return ret;
> -
> -	info->vref_uv = regulator_get_voltage(info->vref);
> +	info->vref_uv = devm_regulator_get_enable_read_voltage(&pdev->dev, "vref");
> +	if (info->vref_uv < 0)
> +		return info->vref_uv;
>   
>   	device_property_read_u32_array(dev, "fsl,adck-max-frequency", info->max_adck_rate, 3);
>   

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