Re: [PATCH v4 3/6] usb: chipidea: imx: add wakeup interrupt handling

[Frank Li <Frank.li@nxp.com>]

On Tue, Mar 04, 2025 at 09:42:21PM +0800, Xu Yang wrote:
> On Mon, Mar 03, 2025 at 12:13:34PM -0500, Frank Li wrote:
> > On Mon, Mar 03, 2025 at 11:33:41AM +0800, Xu Yang wrote:
> > > In previous imx platform, normal USB controller interrupt and wakeup
> > > interrupt are bound to one irq line. However, it changes on latest
> > > i.MX95 platform since it has a dedicated irq line for wakeup interrupt.
> > > This will add wakeup interrupt handling for i.MX95 to support various
> > > wakeup events.
> > >
> > > Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
> > > ---
> > > Changes in v4:
> > >  - warning if no irq provided for imx95
> > > Changes in v3:
> > >  - include <linux/irq.h> to fix possible build issue
> > > Changes in v2:
> > >  - rename irq to wakeup_irq
> > >  - disable irq by default
> > >  - enable irq when suspend, disable irq when resume
> > > ---
> > >  drivers/usb/chipidea/ci_hdrc_imx.c | 35 ++++++++++++++++++++++++++++++
> > >  1 file changed, 35 insertions(+)
> > >
> > > diff --git a/drivers/usb/chipidea/ci_hdrc_imx.c b/drivers/usb/chipidea/ci_hdrc_imx.c
> > > index 1a7fc638213e..2baae9e6e673 100644
> > > --- a/drivers/usb/chipidea/ci_hdrc_imx.c
> > > +++ b/drivers/usb/chipidea/ci_hdrc_imx.c
> > > @@ -6,6 +6,7 @@
> > >   */
> > >
> > >  #include <linux/module.h>
> > > +#include <linux/irq.h>
> > >  #include <linux/of.h>
> > >  #include <linux/of_platform.h>
> > >  #include <linux/platform_device.h>
> > > @@ -98,6 +99,7 @@ struct ci_hdrc_imx_data {
> > >  	struct clk *clk;
> > >  	struct clk *clk_wakeup;
> > >  	struct imx_usbmisc_data *usbmisc_data;
> > > +	int wakeup_irq;
> > >  	bool supports_runtime_pm;
> > >  	bool override_phy_control;
> > >  	bool in_lpm;
> > > @@ -336,6 +338,16 @@ static int ci_hdrc_imx_notify_event(struct ci_hdrc *ci, unsigned int event)
> > >  	return ret;
> > >  }
> > >
> > > +static irqreturn_t ci_wakeup_irq_handler(int irq, void *data)
> > > +{
> > > +	struct ci_hdrc_imx_data *imx_data = data;
> > > +
> > > +	disable_irq_nosync(irq);
> > > +	pm_runtime_resume(&imx_data->ci_pdev->dev);
> > > +
> > > +	return IRQ_HANDLED;
> > > +}
> > > +
> > >  static int ci_hdrc_imx_probe(struct platform_device *pdev)
> > >  {
> > >  	struct ci_hdrc_imx_data *data;
> > > @@ -476,6 +488,18 @@ static int ci_hdrc_imx_probe(struct platform_device *pdev)
> > >  	if (pdata.flags & CI_HDRC_SUPPORTS_RUNTIME_PM)
> > >  		data->supports_runtime_pm = true;
> > >
> > > +	data->wakeup_irq = platform_get_irq_optional(pdev, 1);
> > > +	if (data->wakeup_irq > 0) {
> > > +		ret = devm_request_threaded_irq(dev, data->wakeup_irq,
> > > +						NULL, ci_wakeup_irq_handler,
> > > +						IRQF_ONESHOT | IRQF_NO_AUTOEN,
> > > +						pdata.name, data);
> > > +		if (ret)
> > > +			goto err_clk;
> > > +	} else if (device_is_compatible(dev, "fsl,imx95-usb")) {
> > > +		dev_warn(dev, "wakeup irq is missing\n");
> > > +	}
> > > +
> >
> > Suggest add imx95_usb_data, and new flags, like have_wakeup_irq.
> >
> > 	if (imx_platform_flag->have_wakeup_irq) {
> > 		...
> > 		ret = devm_request_threaded_irq();
> > 		if (ret) {
> > 			dev_warning(...);
> > 			goto err_clk;
> > 		}
> > 	}
>
> Thanks for your suggestion. I might have different understanding about
> it. I prefer to not add flag here. Given the following points:
> (1) the wakeup irq is optional, the USB controller can still functional
> well if properly set. (2) I may need add imx_usb_data for each new Soc,
> however, it seems like unnecessary.

You need add more code about device_is_compatible(dev, "fsl,imx95-usb")

device_is_compatible(dev, "fsl,imx95-usb") |
device_is_compatible(dev, "abc") |
...

the below code will be simple

	if (imx_platform_flag->have_wakeup_irq) {
		data->wakeup_irq = platform_get_irq_optional(pdev, 1);
		if (data->wakeup_irq > 0)
			...
		else
			dev_warn_once(dev, "wakeup irq is missing\n");

	}

Frank

>
> >
> > >  	ret = imx_usbmisc_init(data->usbmisc_data);
> > >  	if (ret) {
> > >  		dev_err(dev, "usbmisc init failed, ret=%d\n", ret);
> > > @@ -584,6 +608,7 @@ static int imx_controller_suspend(struct device *dev,
> > >  	}
> > >
> > >  	imx_disable_unprepare_clks(dev);
> > > +	enable_irq(data->wakeup_irq);
> >
> > Suggest check data->wakeup_irq and other places.
> >
> > 	if (data->wakeup_irq > 0)
> > 		enable_irq(data->wakeup_irq);
> >
> > And you should check enable_irq()'s return value also.
>
> I just find dedicated wakeirq mechanism (drivers/base/power/wakeirq.c)
> basically fit my needs. I'm going to switch to use wakeirq. Then I'll
> needn't to do such thing manually.
>
> Thanks,
> Xu Yang
>
> >
> > Frank
> >
> > >  	if (data->plat_data->flags & CI_HDRC_PMQOS)
> > >  		cpu_latency_qos_remove_request(&data->pm_qos_req);
> > >
> > > @@ -608,6 +633,9 @@ static int imx_controller_resume(struct device *dev,
> > >  	if (data->plat_data->flags & CI_HDRC_PMQOS)
> > >  		cpu_latency_qos_add_request(&data->pm_qos_req, 0);
> > >
> > > +	if (!irqd_irq_disabled(irq_get_irq_data(data->wakeup_irq)))
> > > +		disable_irq_nosync(data->wakeup_irq);
> > > +
> > >  	ret = imx_prepare_enable_clks(dev);
> > >  	if (ret)
> > >  		return ret;
> > > @@ -643,6 +671,10 @@ static int ci_hdrc_imx_suspend(struct device *dev)
> > >  		return ret;
> > >
> > >  	pinctrl_pm_select_sleep_state(dev);
> > > +
> > > +	if (device_may_wakeup(dev))
> > > +		enable_irq_wake(data->wakeup_irq);
> > > +
> > >  	return ret;
> > >  }
> > >
> > > @@ -651,6 +683,9 @@ static int ci_hdrc_imx_resume(struct device *dev)
> > >  	struct ci_hdrc_imx_data *data = dev_get_drvdata(dev);
> > >  	int ret;
> > >
> > > +	if (device_may_wakeup(dev))
> > > +		disable_irq_wake(data->wakeup_irq);
> > > +
> > >  	pinctrl_pm_select_default_state(dev);
> > >  	ret = imx_controller_resume(dev, PMSG_RESUME);
> > >  	if (!ret && data->supports_runtime_pm) {
> > > --
> > > 2.34.1
> > >