From a2a23d3f9e6f44f900e4c4b4cd58f22490c3c200 Mon Sep 17 00:00:00 2001 From: Gregory Herrero Date: Tue, 22 Sep 2015 15:16:40 +0200 Subject: [PATCH] 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: Gregory Herrero Signed-off-by: Mian Yousaf Kaukab Tested-by: Robert Baldyga Tested-by: Dinh Nguyen Tested-by: John Youn Acked-by: John Youn Signed-off-by: Felipe Balbi --- drivers/usb/dwc2/hcd.c | 140 +++++++++++++++++++++++++++++++++++++---- 1 file changed, 128 insertions(+), 12 deletions(-) diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c index 490ecb74382c..459b441e4838 100644 --- a/drivers/usb/dwc2/hcd.c +++ b/drivers/usb/dwc2/hcd.c @@ -1464,11 +1464,17 @@ static void dwc2_port_suspend(struct dwc2_hsotg *hsotg, u16 windex) hsotg->bus_suspended = 1; - /* Suspend the Phy Clock */ - pcgctl = dwc2_readl(hsotg->regs + PCGCTL); - pcgctl |= PCGCTL_STOPPCLK; - dwc2_writel(pcgctl, hsotg->regs + PCGCTL); - udelay(10); + /* + * 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 */ - pcgctl = dwc2_readl(hsotg->regs + PCGCTL); - pcgctl &= ~PCGCTL_STOPPCLK; - dwc2_writel(pcgctl, hsotg->regs + PCGCTL); - usleep_range(20000, 40000); + /* + * 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; + 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; - return 0; + + 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 */ -- 2.34.1