Commit a2a23d3f authored by Gregory Herrero's avatar Gregory Herrero Committed by Felipe Balbi
Browse files

usb: dwc2: host: enter hibernation during bus suspend 



Disable controller power and enter hibernation when usb bus is
suspended. A phy driver is required to disable the power of the
controller and detect remote-wakeup or disconnection since the
controller will not be able to detect these in this state.

Once the phy driver detects bus activity, it must call
usb_hcd_resume_root_hub.

Signed-off-by: default avatarGregory Herrero <gregory.herrero@intel.com>
Signed-off-by: default avatarMian Yousaf Kaukab <yousaf.kaukab@intel.com>
Tested-by: default avatarRobert Baldyga <r.baldyga@samsung.com>
Tested-by: default avatarDinh Nguyen <dinguyen@opensource.altera.com>
Tested-by: default avatarJohn Youn <johnyoun@synopsys.com>
Acked-by: default avatarJohn Youn <johnyoun@synopsys.com>
Signed-off-by: default avatarFelipe Balbi <balbi@ti.com>
parent 734643df

drivers/usb/dwc2/hcd.c

+128 −12
Original line number Diff line number Diff line
@@ -1464,11 +1464,17 @@ static void dwc2_port_suspend(struct dwc2_hsotg *hsotg, u16 windex) 


	hsotg->bus_suspended = 1;



	/*

	 * If hibernation is supported, Phy clock will be suspended

	 * after registers are backuped.

	 */

	if (!hsotg->core_params->hibernation) {

		/* Suspend the Phy Clock */

		pcgctl = dwc2_readl(hsotg->regs + PCGCTL);

		pcgctl |= PCGCTL_STOPPCLK;

		dwc2_writel(pcgctl, hsotg->regs + PCGCTL);

		udelay(10);

	}



	/* For HNP the bus must be suspended for at least 200ms */

	if (dwc2_host_is_b_hnp_enabled(hsotg)) {
@@ -1491,11 +1497,16 @@ static void dwc2_port_resume(struct dwc2_hsotg *hsotg) 
	u32 hprt0;

	u32 pcgctl;



	/* Resume the Phy Clock */

	/*

	 * If hibernation is supported, Phy clock is already resumed

	 * after registers restore.

	 */

	if (!hsotg->core_params->hibernation) {

		pcgctl = dwc2_readl(hsotg->regs + PCGCTL);

		pcgctl &= ~PCGCTL_STOPPCLK;

		dwc2_writel(pcgctl, hsotg->regs + PCGCTL);

		usleep_range(20000, 40000);

	}



	spin_lock_irqsave(&hsotg->lock, flags);

	hprt0 = dwc2_read_hprt0(hsotg);
@@ -2347,17 +2358,122 @@ static void _dwc2_hcd_stop(struct usb_hcd *hcd) 
static int _dwc2_hcd_suspend(struct usb_hcd *hcd)

{

	struct dwc2_hsotg *hsotg = dwc2_hcd_to_hsotg(hcd);

	unsigned long flags;

	int ret = 0;

	u32 hprt0;



	spin_lock_irqsave(&hsotg->lock, flags);



	if (hsotg->lx_state != DWC2_L0)

		goto unlock;



	if (!HCD_HW_ACCESSIBLE(hcd))

		goto unlock;



	if (!hsotg->core_params->hibernation)

		goto skip_power_saving;



	/*

	 * Drive USB suspend and disable port Power

	 * if usb bus is not suspended.

	 */

	if (!hsotg->bus_suspended) {

		hprt0 = dwc2_read_hprt0(hsotg);

		hprt0 |= HPRT0_SUSP;

		hprt0 &= ~HPRT0_PWR;

		dwc2_writel(hprt0, hsotg->regs + HPRT0);

	}



	/* Enter hibernation */

	ret = dwc2_enter_hibernation(hsotg);

	if (ret) {

		if (ret != -ENOTSUPP)

			dev_err(hsotg->dev,

				"enter hibernation failed\n");

		goto skip_power_saving;

	}



	/* Ask phy to be suspended */

	if (!IS_ERR_OR_NULL(hsotg->uphy)) {

		spin_unlock_irqrestore(&hsotg->lock, flags);

		usb_phy_set_suspend(hsotg->uphy, true);

		spin_lock_irqsave(&hsotg->lock, flags);

	}



	/* After entering hibernation, hardware is no more accessible */

	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);



skip_power_saving:

	hsotg->lx_state = DWC2_L2;

	return 0;

unlock:

	spin_unlock_irqrestore(&hsotg->lock, flags);



	return ret;

}



static int _dwc2_hcd_resume(struct usb_hcd *hcd)

{

	struct dwc2_hsotg *hsotg = dwc2_hcd_to_hsotg(hcd);

	unsigned long flags;

	int ret = 0;



	spin_lock_irqsave(&hsotg->lock, flags);



	if (hsotg->lx_state != DWC2_L2)

		goto unlock;



	if (!hsotg->core_params->hibernation) {

		hsotg->lx_state = DWC2_L0;

	return 0;

		goto unlock;

	}



	/*

	 * Set HW accessible bit before powering on the controller

	 * since an interrupt may rise.

	 */

	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);



	/*

	 * Enable power if not already done.

	 * This must not be spinlocked since duration

	 * of this call is unknown.

	 */

	if (!IS_ERR_OR_NULL(hsotg->uphy)) {

		spin_unlock_irqrestore(&hsotg->lock, flags);

		usb_phy_set_suspend(hsotg->uphy, false);

		spin_lock_irqsave(&hsotg->lock, flags);

	}



	/* Exit hibernation */

	ret = dwc2_exit_hibernation(hsotg, true);

	if (ret && (ret != -ENOTSUPP))

		dev_err(hsotg->dev, "exit hibernation failed\n");



	hsotg->lx_state = DWC2_L0;



	spin_unlock_irqrestore(&hsotg->lock, flags);



	if (hsotg->bus_suspended) {

		spin_lock_irqsave(&hsotg->lock, flags);

		hsotg->flags.b.port_suspend_change = 1;

		spin_unlock_irqrestore(&hsotg->lock, flags);

		dwc2_port_resume(hsotg);

	} else {

		/*

		 * Clear Port Enable and Port Status changes.

		 * Enable Port Power.

		 */

		dwc2_writel(HPRT0_PWR | HPRT0_CONNDET |

				HPRT0_ENACHG, hsotg->regs + HPRT0);

		/* Wait for controller to detect Port Connect */

		mdelay(5);

	}



	return ret;

unlock:

	spin_unlock_irqrestore(&hsotg->lock, flags);



	return ret;

}



/* Returns the current frame number */

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