Re: [PATCH v2 1/4] iio: light: cm3605: Make use of the helper function dev_err_probe()

[Jonathan Cameron <jic23@kernel.org>]

On Tue, 28 Sep 2021 09:41:52 +0800
Cai Huoqing <caihuoqing@baidu.com> wrote:

> When possible use dev_err_probe help to properly deal with the
> PROBE_DEFER error, the benefit is that DEFER issue will be logged
> in the devices_deferred debugfs file.
> Using dev_err_probe() can reduce code size, and the error value
> gets printed.
> 
> Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Hi Cai,

This driver has some more cases where we should potentially do something
like this.

It handles the lack of availability of an IIO channel in line 199
by converting an -ENODEV to an -EPROBE_DEFER.

Also platform_get_irq() can return -EPROBE_DEFER and the driver
isn't currently handling that properly.

Both changes are of a more involved nature than the simple conversions you
have here though, so perhaps a follow up patch?

The parts you here look good to me.

Thanks,

Jonathan

> ---
>  drivers/iio/light/cm3605.c | 11 +++++------
>  1 file changed, 5 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/iio/light/cm3605.c b/drivers/iio/light/cm3605.c
> index 4c83953672be..0b90564213e8 100644
> --- a/drivers/iio/light/cm3605.c
> +++ b/drivers/iio/light/cm3605.c
> @@ -211,10 +211,10 @@ static int cm3605_probe(struct platform_device *pdev)
>  	}
>  
>  	cm3605->vdd = devm_regulator_get(dev, "vdd");
> -	if (IS_ERR(cm3605->vdd)) {
> -		dev_err(dev, "failed to get VDD regulator\n");
> -		return PTR_ERR(cm3605->vdd);
> -	}
> +	if (IS_ERR(cm3605->vdd))
> +		return dev_err_probe(dev, PTR_ERR(cm3605->vdd),
> +				     "failed to get VDD regulator\n");
> +
>  	ret = regulator_enable(cm3605->vdd);
>  	if (ret) {
>  		dev_err(dev, "failed to enable VDD regulator\n");
> @@ -223,8 +223,7 @@ static int cm3605_probe(struct platform_device *pdev)
>  
>  	cm3605->aset = devm_gpiod_get(dev, "aset", GPIOD_OUT_HIGH);
>  	if (IS_ERR(cm3605->aset)) {
> -		dev_err(dev, "no ASET GPIO\n");
> -		ret = PTR_ERR(cm3605->aset);
> +		ret = dev_err_probe(dev, PTR_ERR(cm3605->aset), "no ASET GPIO\n");
>  		goto out_disable_vdd;
>  	}
>