Re: [PATCH 1/1] usb: dwc2: platform: adopt dev_err_probe() to silent probe defer

[Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>]

On 12/7/2021 4:08 PM, Amelie Delaunay wrote:
> In case of probe defer, a message is logged for resets and clocks. Use
> dev_err_probe to log the message only when error code is not -517.
> Simplify phy, regulators and drd probe defer handling with dev_err_probe().
> Then, take benefit of devices_deferred debugfs in case of probe deferral.
> 
> Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>

Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>

> ---
>   drivers/usb/dwc2/platform.c | 53 +++++++++++--------------------------
>   1 file changed, 16 insertions(+), 37 deletions(-)
> 
> diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
> index c8f18f3ba9e3..a1feaa09be57 100644
> --- a/drivers/usb/dwc2/platform.c
> +++ b/drivers/usb/dwc2/platform.c
> @@ -222,20 +222,16 @@ static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
>   	int i, ret;
>   
>   	hsotg->reset = devm_reset_control_get_optional(hsotg->dev, "dwc2");
> -	if (IS_ERR(hsotg->reset)) {
> -		ret = PTR_ERR(hsotg->reset);
> -		dev_err(hsotg->dev, "error getting reset control %d\n", ret);
> -		return ret;
> -	}
> +	if (IS_ERR(hsotg->reset))
> +		return dev_err_probe(hsotg->dev, PTR_ERR(hsotg->reset),
> +				     "error getting reset control\n");
>   
>   	reset_control_deassert(hsotg->reset);
>   
>   	hsotg->reset_ecc = devm_reset_control_get_optional(hsotg->dev, "dwc2-ecc");
> -	if (IS_ERR(hsotg->reset_ecc)) {
> -		ret = PTR_ERR(hsotg->reset_ecc);
> -		dev_err(hsotg->dev, "error getting reset control for ecc %d\n", ret);
> -		return ret;
> -	}
> +	if (IS_ERR(hsotg->reset_ecc))
> +		return dev_err_probe(hsotg->dev, PTR_ERR(hsotg->reset_ecc),
> +				     "error getting reset control for ecc\n");
>   
>   	reset_control_deassert(hsotg->reset_ecc);
>   
> @@ -251,11 +247,8 @@ static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
>   		case -ENOSYS:
>   			hsotg->phy = NULL;
>   			break;
> -		case -EPROBE_DEFER:
> -			return ret;
>   		default:
> -			dev_err(hsotg->dev, "error getting phy %d\n", ret);
> -			return ret;
> +			return dev_err_probe(hsotg->dev, ret, "error getting phy\n");
>   		}
>   	}
>   
> @@ -268,12 +261,8 @@ static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
>   			case -ENXIO:
>   				hsotg->uphy = NULL;
>   				break;
> -			case -EPROBE_DEFER:
> -				return ret;
>   			default:
> -				dev_err(hsotg->dev, "error getting usb phy %d\n",
> -					ret);
> -				return ret;
> +				return dev_err_probe(hsotg->dev, ret, "error getting usb phy\n");
>   			}
>   		}
>   	}
> @@ -282,10 +271,8 @@ static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
>   
>   	/* Clock */
>   	hsotg->clk = devm_clk_get_optional(hsotg->dev, "otg");
> -	if (IS_ERR(hsotg->clk)) {
> -		dev_err(hsotg->dev, "cannot get otg clock\n");
> -		return PTR_ERR(hsotg->clk);
> -	}
> +	if (IS_ERR(hsotg->clk))
> +		return dev_err_probe(hsotg->dev, PTR_ERR(hsotg->clk), "cannot get otg clock\n");
>   
>   	/* Regulators */
>   	for (i = 0; i < ARRAY_SIZE(hsotg->supplies); i++)
> @@ -293,12 +280,9 @@ static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
>   
>   	ret = devm_regulator_bulk_get(hsotg->dev, ARRAY_SIZE(hsotg->supplies),
>   				      hsotg->supplies);
> -	if (ret) {
> -		if (ret != -EPROBE_DEFER)
> -			dev_err(hsotg->dev, "failed to request supplies: %d\n",
> -				ret);
> -		return ret;
> -	}
> +	if (ret)
> +		return dev_err_probe(hsotg->dev, ret, "failed to request supplies\n");
> +
>   	return 0;
>   }
>   
> @@ -558,16 +542,12 @@ static int dwc2_driver_probe(struct platform_device *dev)
>   		hsotg->usb33d = devm_regulator_get(hsotg->dev, "usb33d");
>   		if (IS_ERR(hsotg->usb33d)) {
>   			retval = PTR_ERR(hsotg->usb33d);
> -			if (retval != -EPROBE_DEFER)
> -				dev_err(hsotg->dev,
> -					"failed to request usb33d supply: %d\n",
> -					retval);
> +			dev_err_probe(hsotg->dev, retval, "failed to request usb33d supply\n");
>   			goto error;
>   		}
>   		retval = regulator_enable(hsotg->usb33d);
>   		if (retval) {
> -			dev_err(hsotg->dev,
> -				"failed to enable usb33d supply: %d\n", retval);
> +			dev_err_probe(hsotg->dev, retval, "failed to enable usb33d supply\n");
>   			goto error;
>   		}
>   
> @@ -579,8 +559,7 @@ static int dwc2_driver_probe(struct platform_device *dev)
>   
>   	retval = dwc2_drd_init(hsotg);
>   	if (retval) {
> -		if (retval != -EPROBE_DEFER)
> -			dev_err(hsotg->dev, "failed to initialize dual-role\n");
> +		dev_err_probe(hsotg->dev, retval, "failed to initialize dual-role\n");
>   		goto error_init;
>   	}
>