Re: [PATCH] usb: chipidea: ci_hdrc_imx: Propagate -EPROBE_DEFER from IRQ lookup

Hi Greg,

Thank you for your feedback.

> > From: bui duc phuc <[email protected]>
>
> All lower case?
>

Yes, I’ll keep it lowercase.

> > Return -EPROBE_DEFER from platform_get_irq_optional() so the driver is
> > re-probed when the interrupt resource becomes available instead of
> > continuing probe without an IRQ.
>
> How was this found and tested?
>

I found this during code inspection while cleaning up probe functions in
the Rockchip ASoC drivers.

https://lore.kernel.org/all/[email protected]/

platform_get_irq_optional() returns a positive IRQ number on success or
a negative error code on failure, including -EPROBE_DEFER. The driver
handled positive IRQ numbers but ignored -EPROBE_DEFER, continuing
probe without an IRQ instead of deferring.

I only compile-tested the change. I don't have the hardware to test this
path at runtime.

While reviewing this,I noticed that -EINVAL also deserves to be returned,
not just -EPROBE_DEFER only -ENXIO really means "no IRQ".
I’ll update this to:

if (data->wakeup_irq < 0 && data->wakeup_irq != -ENXIO) {
        ret = data->wakeup_irq;
        goto err_clk;
}

I also found another issue in the same area:

        if (data->wakeup_irq > 0) {
                irq_name = devm_kasprintf(dev, GFP_KERNEL,
"%s:wakeup", pdata.name);
                if (!irq_name) {
-                       dev_err_probe(dev, -ENOMEM, "failed to create
irq_name\n");
+                       ret = dev_err_probe(dev, -ENOMEM, "failed to
create irq_name\n");
                        goto err_clk;
                }


the error return from dev_err_probe() was not assigned to ret,  so the
error path could still return 0.
I’ll send v2 soon.

Best regards,
Phuc