Re: [PATCH v16 7/9] usb: dwc3: qcom: Refactor IRQ handling in glue driver

[Johan Hovold <johan@kernel.org>]

On Thu, Mar 07, 2024 at 11:50:50AM +0530, Krishna Kurapati wrote:
> On multiport supported controllers, each port has its own DP/DM
> and SS (if super speed capable) interrupts. As per the bindings,
> their interrupt names differ from standard ones having "_x" added
> as suffix (x indicates port number). Identify from the interrupt
> names whether the controller is a multiport controller or not.
> Refactor dwc3_qcom_setup_irq() call to parse multiport interrupts
> along with non-multiport ones accordingly..
> 
> Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
> ---
>  drivers/usb/dwc3/dwc3-qcom.c | 146 +++++++++++++++++++++++++++--------
>  1 file changed, 112 insertions(+), 34 deletions(-)

This is much better. Just a couple of nits below.

> +static int dwc3_qcom_find_num_ports(struct platform_device *pdev)
> +{
> +	const char *irq_name;
> +	int port_index;
> +	int irq;
> +
> +	irq = platform_get_irq_byname_optional(pdev, "qusb2_phy");
> +	if (irq > 0)
> +		return 1;
> +
> +	irq = platform_get_irq_byname_optional(pdev, "dp_hs_phy_irq");
> +	if (irq > 0)
> +		return 1;
> +
> +	for (port_index = 0; port_index < DWC3_MAX_PORTS; port_index++) {
> +		irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "dp_hs_phy_%d", port_index + 1);

Please use a stack allocated buffer for these strings as we don't need
them any more after this function returns.

> +		if (!irq_name)
> +			return -ENOMEM;
> +
> +		irq = platform_get_irq_byname_optional(pdev, irq_name);
> +		if (irq <= 0)
> +			return port_index;
> +	}
> +
> +	return port_index;

I think explicitly returning DWC3_MAX_PORTS here would be more readable.

> +}
> +
> +static int dwc3_qcom_setup_irq(struct platform_device *pdev)
> +{
> +	struct dwc3_qcom *qcom = platform_get_drvdata(pdev);
> +	bool is_multiport;
> +	int ret;
> +	int i;
> +
> +	qcom->num_ports = dwc3_qcom_find_num_ports(pdev);
> +	if (qcom->num_ports < 0)
> +		return -ENOMEM;

Just return 'ret' directly.

> +
> +	is_multiport = (qcom->num_ports > 1) ? true : false;

And no need for the ternary operator:

	is_multiport = (qcom->num_ports > 1);

> +
> +	for (i = 0; i < qcom->num_ports; i++) {
> +		ret = dwc3_qcom_setup_port_irq(pdev, i, is_multiport);
>  		if (ret)
>  			return ret;
> -		qcom->ss_phy_irq = irq;
>  	}
>  
>  	return 0;

With that fixed:

Reviewed-by: Johan Hovold <johan+linaro@kernel.org>