Re: [PATCH v20 4/5] usb: dwc3: qcom: Configure wakeup interrupts during suspend

[Pavan Kondeti <quic_pkondeti@quicinc.com>]

On Thu, Jun 02, 2022 at 01:54:36PM +0530, Krishna Kurapati wrote:
> From: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
> 
> Configure DP/DM line interrupts based on the USB2 device attached to
> the root hub port. When HS/FS device is connected, configure the DP line
> as falling edge to detect both disconnect and remote wakeup scenarios. When
> LS device is connected, configure DM line as falling edge to detect both
> disconnect and remote wakeup. When no device is connected, configure both
> DP and DM lines as rising edge to detect HS/HS/LS device connect scenario.
> 
> Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
> Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
> ---
>  drivers/usb/dwc3/dwc3-qcom.c | 72 ++++++++++++++++++++++++++++++++++++++------
>  1 file changed, 62 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
> index 7352124..9395d79 100644
> --- a/drivers/usb/dwc3/dwc3-qcom.c
> +++ b/drivers/usb/dwc3/dwc3-qcom.c
> @@ -20,7 +20,8 @@
>  #include <linux/usb/of.h>
>  #include <linux/reset.h>
>  #include <linux/iopoll.h>
> -
> +#include <linux/usb/hcd.h>
> +#include <linux/usb.h>
>  #include "core.h"
>  
>  /* USB QSCRATCH Hardware registers */
> @@ -76,6 +77,7 @@ struct dwc3_qcom {
>  	int			dp_hs_phy_irq;
>  	int			dm_hs_phy_irq;
>  	int			ss_phy_irq;
> +	enum usb_device_speed	usb2_speed;
>  
>  	struct extcon_dev	*edev;
>  	struct extcon_dev	*host_edev;
> @@ -296,11 +298,34 @@ static void dwc3_qcom_interconnect_exit(struct dwc3_qcom *qcom)
>  	icc_put(qcom->icc_path_apps);
>  }
>  
> -static void dwc3_qcom_enable_wakeup_irq(int irq)
> +enum usb_device_speed dwc3_qcom_read_usb2_speed(struct dwc3_qcom *qcom)
> +{
> +	struct dwc3 *dwc = platform_get_drvdata(qcom->dwc3);
> +	struct usb_hcd *hcd = platform_get_drvdata(dwc->xhci);
> +	struct usb_device *udev;
> +
> +	/*
> +	 * It is possible to query the speed of all children of
> +	 * USB2.0 root hub via usb_hub_for_each_child(). DWC3 code
> +	 * currently supports only 1 port per controller. So
> +	 * this is sufficient.
> +	 */
> +	udev = usb_hub_find_child(hcd->self.root_hub, 1);
> +
> +	if (!udev)
> +		return USB_SPEED_UNKNOWN;
> +
> +	return udev->speed;
> +}
> +
> +static void dwc3_qcom_enable_wakeup_irq(int irq, unsigned int polarity)
>  {
>  	if (!irq)
>  		return;
>  
> +	if (polarity)
> +		irq_set_irq_type(irq, polarity);
> +
>  	enable_irq(irq);
>  	enable_irq_wake(irq);
>  }
> @@ -318,22 +343,47 @@ static void dwc3_qcom_disable_interrupts(struct dwc3_qcom *qcom)
>  {
>  	dwc3_qcom_disable_wakeup_irq(qcom->hs_phy_irq);
>  
> -	dwc3_qcom_disable_wakeup_irq(qcom->dp_hs_phy_irq);
> -
> -	dwc3_qcom_disable_wakeup_irq(qcom->dm_hs_phy_irq);
> +	if (qcom->usb2_speed == USB_SPEED_LOW) {
> +		dwc3_qcom_disable_wakeup_irq(qcom->dm_hs_phy_irq);
> +	} else if ((qcom->usb2_speed == USB_SPEED_HIGH) ||
> +			(qcom->usb2_speed == USB_SPEED_FULL)) {
> +		dwc3_qcom_disable_wakeup_irq(qcom->dp_hs_phy_irq);
> +	} else {
> +		dwc3_qcom_disable_wakeup_irq(qcom->dp_hs_phy_irq);
> +		dwc3_qcom_disable_wakeup_irq(qcom->dm_hs_phy_irq);
> +	}
>  
>  	dwc3_qcom_disable_wakeup_irq(qcom->ss_phy_irq);
>  }
>  
>  static void dwc3_qcom_enable_interrupts(struct dwc3_qcom *qcom)
>  {
> -	dwc3_qcom_enable_wakeup_irq(qcom->hs_phy_irq);
> +	dwc3_qcom_enable_wakeup_irq(qcom->hs_phy_irq, 0);
>  
> -	dwc3_qcom_enable_wakeup_irq(qcom->dp_hs_phy_irq);
> +	/*
> +	 * Configure DP/DM line interrupts based on the USB2 device attached to
> +	 * the root hub port. When HS/FS device is connected, configure the DP line
> +	 * as falling edge to detect both disconnect and remote wakeup scenarios. When
> +	 * LS device is connected, configure DM line as falling edge to detect both
> +	 * disconnect and remote wakeup. When no device is connected, configure both
> +	 * DP and DM lines as rising edge to detect HS/HS/LS device connect scenario.
> +	 */
>  
> -	dwc3_qcom_enable_wakeup_irq(qcom->dm_hs_phy_irq);
> +	if (qcom->usb2_speed == USB_SPEED_LOW) {
> +		dwc3_qcom_enable_wakeup_irq(qcom->dm_hs_phy_irq,
> +						IRQ_TYPE_EDGE_FALLING);
> +	} else if ((qcom->usb2_speed == USB_SPEED_HIGH) ||
> +			(qcom->usb2_speed == USB_SPEED_FULL)) {
> +		dwc3_qcom_enable_wakeup_irq(qcom->dp_hs_phy_irq,
> +						IRQ_TYPE_EDGE_FALLING);
> +	} else {
> +		dwc3_qcom_enable_wakeup_irq(qcom->dp_hs_phy_irq,
> +						IRQ_TYPE_EDGE_RISING);
> +		dwc3_qcom_enable_wakeup_irq(qcom->dm_hs_phy_irq,
> +						IRQ_TYPE_EDGE_RISING);
> +	}
>  
> -	dwc3_qcom_enable_wakeup_irq(qcom->ss_phy_irq);
> +	dwc3_qcom_enable_wakeup_irq(qcom->ss_phy_irq, 0);
>  }
>  
>  static int dwc3_qcom_suspend(struct dwc3_qcom *qcom)
> @@ -355,8 +405,10 @@ static int dwc3_qcom_suspend(struct dwc3_qcom *qcom)
>  	if (ret)
>  		dev_warn(qcom->dev, "failed to disable interconnect: %d\n", ret);
>  
> -	if (device_may_wakeup(qcom->dev))
> +	if (device_may_wakeup(qcom->dev)) {
> +		qcom->usb2_speed = dwc3_qcom_read_usb2_speed(qcom);
>  		dwc3_qcom_enable_interrupts(qcom);
> +	}
>  
>  	qcom->is_suspended = true;
>  

Looks good to me.

Reviewed-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>

Thanks,
Pavan