RE: [PATCH v2 2/9] usb: cdns3: add runtime PM support

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi,

> -----Original Message-----
> From: Peter Chen <peter.chen@xxxxxxx>
> Sent: 2020年5月24日 7:23
> To: balbi@xxxxxxxxxx; mathias.nyman@xxxxxxxxx
> Cc: linux-usb@xxxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>;
> pawell@xxxxxxxxxxx; rogerq@xxxxxx; gregkh@xxxxxxxxxxxxxxxxxxx; Jun Li
> <jun.li@xxxxxxx>; Peter Chen <peter.chen@xxxxxxx>
> Subject: [PATCH v2 2/9] usb: cdns3: add runtime PM support
> 
> Introduce runtime PM and wakeup interrupt handler for cdns3, the runtime PM is default
> off since other cdns3 has not implemented glue layer support for runtime PM.
> 
> When the controller is in low power mode, the lpm flag will be set.
> The interrupt triggered later than lpm flag is set considers as wakeup interrupt
> and handled at cdns_drd_irq. Once the wakeup occurs, it first disables interrupt
> to avoid later interrupt occurrence since the controller is in low power mode at
> that time, and access registers may be invalid at that time. At wakeup handler,
> it will call pm_runtime_get to wakeup controller, and at runtime resume handler,
> it will enable interrupt again.
> 
> The API platform_suspend is introduced for glue layer to implement platform specific
> PM sequence.
> 
> Signed-off-by: Peter Chen <peter.chen@xxxxxxx>
> ---
>  drivers/usb/cdns3/core.c   | 119 +++++++++++++++++++++++++++++++------
>  drivers/usb/cdns3/core.h   |  14 +++++
>  drivers/usb/cdns3/drd.c    |   7 +++
>  drivers/usb/cdns3/gadget.c |   4 ++
>  drivers/usb/cdns3/host.c   |   7 +++
>  5 files changed, 134 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c index
> bfd09aa98c12..5221c1306e64 100644
> --- a/drivers/usb/cdns3/core.c
> +++ b/drivers/usb/cdns3/core.c
> @@ -432,6 +432,7 @@ static int cdns3_probe(struct platform_device *pdev)
>  		return -ENOMEM;
> 
>  	cdns->dev = dev;
> +	cdns->pdata = dev_get_platdata(dev);
> 
>  	platform_set_drvdata(pdev, cdns);
> 
> @@ -525,9 +526,11 @@ static int cdns3_probe(struct platform_device *pdev)
>  	if (ret)
>  		goto err4;
> 
> +	spin_lock_init(&cdns->lock);
>  	device_set_wakeup_capable(dev, true);
>  	pm_runtime_set_active(dev);
>  	pm_runtime_enable(dev);
> +	pm_runtime_forbid(dev);
> 
>  	/*
>  	 * The controller needs less time between bus and controller suspend, @@ -574,52
> +577,134 @@ static int cdns3_remove(struct platform_device *pdev)
>  	return 0;
>  }
> 
> -#ifdef CONFIG_PM_SLEEP
> +#ifdef CONFIG_PM

__maybe_unused

> 
> -static int cdns3_suspend(struct device *dev)
> +static int cdns3_set_platform_suspend(struct device *dev,
> +		bool suspend, bool wakeup)
> +{
> +	struct cdns3 *cdns = dev_get_drvdata(dev);
> +	int ret = 0;
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&cdns->lock, flags);
> +	if (cdns->pdata && cdns->pdata->platform_suspend)
> +		ret = cdns->pdata->platform_suspend(dev, suspend, wakeup);
> +
> +	spin_unlock_irqrestore(&cdns->lock, flags);
> +
> +	return ret;
> +}
> +
> +static int cdns3_controller_suspend(struct device *dev, pm_message_t
> +msg)
>  {
>  	struct cdns3 *cdns = dev_get_drvdata(dev);
> +	bool wakeup;
>  	unsigned long flags;
> 
> -	if (cdns->role == USB_ROLE_HOST)
> +	if (cdns->in_lpm)
>  		return 0;
> 
> -	if (pm_runtime_status_suspended(dev))
> -		pm_runtime_resume(dev);
> +	if (PMSG_IS_AUTO(msg))
> +		wakeup = true;
> +	else
> +		wakeup = false;

wakeup = device_may_wakeup(dev)?

> 
> -	if (cdns->roles[cdns->role]->suspend) {
> -		spin_lock_irqsave(&cdns->gadget_dev->lock, flags);
> -		cdns->roles[cdns->role]->suspend(cdns, false);
> -		spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags);
> -	}
> +	cdns3_set_platform_suspend(cdns->dev, true, wakeup);
> +	cdns3_set_phy_power(cdns, false);
> +	spin_lock_irqsave(&cdns->lock, flags);
> +	cdns->in_lpm = true;
> +	spin_unlock_irqrestore(&cdns->lock, flags);
> 
>  	return 0;
>  }
> 
> -static int cdns3_resume(struct device *dev)
> +static int cdns3_controller_resume(struct device *dev, pm_message_t
> +msg)
>  {
>  	struct cdns3 *cdns = dev_get_drvdata(dev);
> +	int ret;
>  	unsigned long flags;
> 
> -	if (cdns->role == USB_ROLE_HOST)
> +	if (!cdns->in_lpm)
>  		return 0;
> 
> -	if (cdns->roles[cdns->role]->resume) {
> -		spin_lock_irqsave(&cdns->gadget_dev->lock, flags);
> +	ret = cdns3_set_phy_power(cdns, true);
> +	if (ret)
> +		return ret;
> +
> +	cdns3_set_platform_suspend(cdns->dev, false, false);
> +
> +	spin_lock_irqsave(&cdns->lock, flags);
> +	if (cdns->roles[cdns->role]->resume && !PMSG_IS_AUTO(msg))
>  		cdns->roles[cdns->role]->resume(cdns, false);
> -		spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags);
> +
> +	cdns->in_lpm = false;
> +	spin_unlock_irqrestore(&cdns->lock, flags);
> +	if (cdns->wakeup_int) {
> +		cdns->wakeup_int = false;
> +		if (cdns->role == USB_ROLE_HOST) {
> +			/* Trigger xhci-plat.c runtime runtime */
> +			pm_runtime_get(&cdns->host_dev->dev);
> +			pm_runtime_mark_last_busy(&cdns->host_dev->dev);
> +			pm_runtime_put_autosuspend(&cdns->host_dev->dev);
> +			/* balence the pm_runtime_get at cdns3_drd_irq */

%s/balence/balance

> +			pm_runtime_mark_last_busy(cdns->dev);
> +			pm_runtime_put_autosuspend(cdns->dev);

A simple
if (cdns->role == USB_ROLE_HOST)
      pm_runtime_resume(&cdns->host_dev->dev);
in low power event handler can't work?

> +		}
> +
> +		enable_irq(cdns->otg_irq);
> +	}
> +
> +	return ret;
> +}
> +
> +static int cdns3_runtime_suspend(struct device *dev) {
> +	return cdns3_controller_suspend(dev, PMSG_AUTO_SUSPEND); }
> +
> +static int cdns3_runtime_resume(struct device *dev) {
> +	return cdns3_controller_resume(dev, PMSG_AUTO_RESUME); } #ifdef
> +CONFIG_PM_SLEEP
> +
> +static int cdns3_suspend(struct device *dev) {
> +	struct cdns3 *cdns = dev_get_drvdata(dev);
> +	unsigned long flags;
> +
> +	if (pm_runtime_status_suspended(dev))
> +		pm_runtime_resume(dev);
> +
> +	if (cdns->roles[cdns->role]->suspend) {
> +		spin_lock_irqsave(&cdns->lock, flags);
> +		cdns->roles[cdns->role]->suspend(cdns, false);

Seems this hasn't been used, I did not find the implementation.
this role->suspend() is only to be used in system suspend but not in runtime suspend?

> +		spin_unlock_irqrestore(&cdns->lock, flags);
>  	}
> 
> +	return cdns3_controller_suspend(dev, PMSG_SUSPEND); }
> +
> +static int cdns3_resume(struct device *dev) {
> +	int ret;
> +
> +	ret = cdns3_controller_resume(dev, PMSG_RESUME);
> +	if (ret)
> +		return ret;
> +
>  	pm_runtime_disable(dev);
>  	pm_runtime_set_active(dev);
>  	pm_runtime_enable(dev);
> 
> -	return 0;
> +	return ret;
>  }
> -#endif
> +#endif /* CONFIG_PM_SLEEP */
> +#endif /* CONFIG_PM */
> 
>  static const struct dev_pm_ops cdns3_pm_ops = {
>  	SET_SYSTEM_SLEEP_PM_OPS(cdns3_suspend, cdns3_resume)
> +	SET_RUNTIME_PM_OPS(cdns3_runtime_suspend, cdns3_runtime_resume, NULL)
>  };
> 
>  #ifdef CONFIG_OF
> diff --git a/drivers/usb/cdns3/core.h b/drivers/usb/cdns3/core.h index
> 1ad1f1fe61e9..9eb8aeea2d20 100644
> --- a/drivers/usb/cdns3/core.h
> +++ b/drivers/usb/cdns3/core.h
> @@ -38,6 +38,12 @@ struct cdns3_role_driver {  };
> 
>  #define CDNS3_XHCI_RESOURCES_NUM	2
> +
> +struct cdns3_platform_data {
> +	int (*platform_suspend)(struct device *dev,
> +			bool suspend, bool wakeup);
> +};
> +
>  /**
>   * struct cdns3 - Representation of Cadence USB3 DRD controller.
>   * @dev: pointer to Cadence device struct @@ -62,6 +68,10 @@ struct
> cdns3_role_driver {
>   *           This field based on firmware setting, kernel configuration
>   *           and hardware configuration.
>   * @role_sw: pointer to role switch object.
> + * @in_lpm: indicate the controller is in low power mode
> + * @wakeup_int: wakeup interrupt occurs
> + * @pdata: platform data from glue layer
> + * @lock: spinlock structure
>   */
>  struct cdns3 {
>  	struct device			*dev;
> @@ -89,6 +99,10 @@ struct cdns3 {
>  	struct mutex			mutex;
>  	enum usb_dr_mode		dr_mode;
>  	struct usb_role_switch		*role_sw;
> +	bool				in_lpm;
> +	bool				wakeup_int;
> +	struct cdns3_platform_data	*pdata;
> +	spinlock_t			lock;
>  };
> 
>  int cdns3_hw_role_switch(struct cdns3 *cdns); diff --git
> a/drivers/usb/cdns3/drd.c b/drivers/usb/cdns3/drd.c index
> 58089841ed52..292ea248c0ec 100644
> --- a/drivers/usb/cdns3/drd.c
> +++ b/drivers/usb/cdns3/drd.c
> @@ -278,6 +278,13 @@ static irqreturn_t cdns3_drd_irq(int irq, void *data)
>  	struct cdns3 *cdns = data;
>  	u32 reg;
> 
> +	if (cdns->in_lpm) {
> +		disable_irq_nosync(irq);
> +		cdns->wakeup_int = true;
> +		pm_runtime_get(cdns->dev);
> +		return IRQ_HANDLED;
> +	}

All low power events go through otg irq?

Li Jun

> +
>  	if (cdns->dr_mode != USB_DR_MODE_OTG)
>  		return ret;
> 
> diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c index
> 559e5c01c2b0..ccb257d9daa6 100644
> --- a/drivers/usb/cdns3/gadget.c
> +++ b/drivers/usb/cdns3/gadget.c
> @@ -1766,9 +1766,13 @@ static void cdns3_check_usb_interrupt_proceed(struct
> cdns3_device *priv_dev,  static irqreturn_t cdns3_device_irq_handler(int irq,
> void *data)  {
>  	struct cdns3_device *priv_dev = data;
> +	struct cdns3 *cdns = dev_get_drvdata(priv_dev->dev);
>  	irqreturn_t ret = IRQ_NONE;
>  	u32 reg;
> 
> +	if (cdns->in_lpm)
> +		return ret;
> +
>  	/* check USB device interrupt */
>  	reg = readl(&priv_dev->regs->usb_ists);
>  	if (reg) {
> diff --git a/drivers/usb/cdns3/host.c b/drivers/usb/cdns3/host.c index
> ad788bf3fe4f..b579ef15f4e0 100644
> --- a/drivers/usb/cdns3/host.c
> +++ b/drivers/usb/cdns3/host.c
> @@ -13,11 +13,13 @@
>  #include "core.h"
>  #include "drd.h"
>  #include "host-export.h"
> +#include <linux/usb/hcd.h>
> 
>  static int __cdns3_host_init(struct cdns3 *cdns)  {
>  	struct platform_device *xhci;
>  	int ret;
> +	struct usb_hcd *hcd;
> 
>  	cdns3_drd_switch_host(cdns, 1);
> 
> @@ -43,6 +45,11 @@ static int __cdns3_host_init(struct cdns3 *cdns)
>  		goto err1;
>  	}
> 
> +	/* Glue needs to access xHCI region register for Power management */
> +	hcd = platform_get_drvdata(xhci);
> +	if (hcd)
> +		cdns->xhci_regs = hcd->regs;
> +
>  	return 0;
>  err1:
>  	platform_device_put(xhci);
> --
> 2.17.1





[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux