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

[Xu Yang <xu.yang_2@nxp.com>]

On Tue, Mar 04, 2025 at 10:50:06AM +0100, Alexander Stein wrote:
> Am Montag, 3. März 2025, 04:33:41 CET schrieb Xu Yang:
> > 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");
> > +	}
> > +
> >  	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);
> >  	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);
> > +
> 
> if (data->wakeup_irq > 0) is necessary. I'll get a NULL-pointer
> dereference on imx93.

Okay. Thanks!

Best Regards,
Xu Yang

> 
> Best regards
> Alexander
> 
> >  	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) {
> > 
> 
> 
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