Re: [PATCH 10/11] USB: dwc3: refactor clock lookups

[Thinh Nguyen <Thinh.Nguyen@synopsys.com>]

On Tue, Apr 04, 2023, Johan Hovold wrote:
> The probe callback has become unwieldy so break out the clock lookups
> into a new helper function to improve readability.
> 
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
> ---
>  drivers/usb/dwc3/core.c | 116 +++++++++++++++++++++-------------------
>  1 file changed, 61 insertions(+), 55 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 52cd5ddfebd5..08432e109a3f 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -1692,6 +1692,64 @@ static struct extcon_dev *dwc3_get_extcon(struct dwc3 *dwc)
>  	return edev;
>  }
>  
> +static int dwc3_get_clocks(struct dwc3 *dwc)
> +{
> +	struct device *dev = dwc->dev;
> +
> +	if (!dev->of_node)
> +		return 0;
> +
> +	/*
> +	 * Clocks are optional, but new DT platforms should support all clocks
> +	 * as required by the DT-binding.
> +	 * Some devices have different clock names in legacy device trees,
> +	 * check for them to retain backwards compatibility.
> +	 */
> +	dwc->bus_clk = devm_clk_get_optional(dev, "bus_early");
> +	if (IS_ERR(dwc->bus_clk)) {
> +		return dev_err_probe(dev, PTR_ERR(dwc->bus_clk),
> +				"could not get bus clock\n");
> +	}
> +
> +	if (dwc->bus_clk == NULL) {
> +		dwc->bus_clk = devm_clk_get_optional(dev, "bus_clk");
> +		if (IS_ERR(dwc->bus_clk)) {
> +			return dev_err_probe(dev, PTR_ERR(dwc->bus_clk),
> +					"could not get bus clock\n");
> +		}
> +	}
> +
> +	dwc->ref_clk = devm_clk_get_optional(dev, "ref");
> +	if (IS_ERR(dwc->ref_clk)) {
> +		return dev_err_probe(dev, PTR_ERR(dwc->ref_clk),
> +				"could not get ref clock\n");
> +	}
> +
> +	if (dwc->ref_clk == NULL) {
> +		dwc->ref_clk = devm_clk_get_optional(dev, "ref_clk");
> +		if (IS_ERR(dwc->ref_clk)) {
> +			return dev_err_probe(dev, PTR_ERR(dwc->ref_clk),
> +					"could not get ref clock\n");
> +		}
> +	}
> +
> +	dwc->susp_clk = devm_clk_get_optional(dev, "suspend");
> +	if (IS_ERR(dwc->susp_clk)) {
> +		return dev_err_probe(dev, PTR_ERR(dwc->susp_clk),
> +				"could not get suspend clock\n");
> +	}
> +
> +	if (dwc->susp_clk == NULL) {
> +		dwc->susp_clk = devm_clk_get_optional(dev, "suspend_clk");
> +		if (IS_ERR(dwc->susp_clk)) {
> +			return dev_err_probe(dev, PTR_ERR(dwc->susp_clk),
> +					"could not get suspend clock\n");
> +		}
> +	}
> +
> +	return 0;
> +}
> +
>  static int dwc3_probe(struct platform_device *pdev)
>  {
>  	struct device		*dev = &pdev->dev;
> @@ -1742,61 +1800,9 @@ static int dwc3_probe(struct platform_device *pdev)
>  		goto err_put_psy;
>  	}
>  
> -	if (dev->of_node) {
> -		/*
> -		 * Clocks are optional, but new DT platforms should support all
> -		 * clocks as required by the DT-binding.
> -		 * Some devices have different clock names in legacy device trees,
> -		 * check for them to retain backwards compatibility.
> -		 */
> -		dwc->bus_clk = devm_clk_get_optional(dev, "bus_early");
> -		if (IS_ERR(dwc->bus_clk)) {
> -			ret = dev_err_probe(dev, PTR_ERR(dwc->bus_clk),
> -					    "could not get bus clock\n");
> -			goto err_put_psy;
> -		}
> -
> -		if (dwc->bus_clk == NULL) {
> -			dwc->bus_clk = devm_clk_get_optional(dev, "bus_clk");
> -			if (IS_ERR(dwc->bus_clk)) {
> -				ret = dev_err_probe(dev, PTR_ERR(dwc->bus_clk),
> -						    "could not get bus clock\n");
> -				goto err_put_psy;
> -			}
> -		}
> -
> -		dwc->ref_clk = devm_clk_get_optional(dev, "ref");
> -		if (IS_ERR(dwc->ref_clk)) {
> -			ret = dev_err_probe(dev, PTR_ERR(dwc->ref_clk),
> -					    "could not get ref clock\n");
> -			goto err_put_psy;
> -		}
> -
> -		if (dwc->ref_clk == NULL) {
> -			dwc->ref_clk = devm_clk_get_optional(dev, "ref_clk");
> -			if (IS_ERR(dwc->ref_clk)) {
> -				ret = dev_err_probe(dev, PTR_ERR(dwc->ref_clk),
> -						    "could not get ref clock\n");
> -				goto err_put_psy;
> -			}
> -		}
> -
> -		dwc->susp_clk = devm_clk_get_optional(dev, "suspend");
> -		if (IS_ERR(dwc->susp_clk)) {
> -			ret = dev_err_probe(dev, PTR_ERR(dwc->susp_clk),
> -					    "could not get suspend clock\n");
> -			goto err_put_psy;
> -		}
> -
> -		if (dwc->susp_clk == NULL) {
> -			dwc->susp_clk = devm_clk_get_optional(dev, "suspend_clk");
> -			if (IS_ERR(dwc->susp_clk)) {
> -				ret = dev_err_probe(dev, PTR_ERR(dwc->susp_clk),
> -						    "could not get suspend clock\n");
> -				goto err_put_psy;
> -			}
> -		}
> -	}
> +	ret = dwc3_get_clocks(dwc);
> +	if (ret)
> +		goto err_put_psy;
>  
>  	ret = reset_control_deassert(dwc->reset);
>  	if (ret)
> -- 
> 2.39.2
> 

Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>

Thanks,
Thinh