From f0e36d478faf37fb26413b2530d04e6b30af3834 Mon Sep 17 00:00:00 2001 From: Martin Blumenstingl Date: Wed, 18 Apr 2018 21:39:48 +0200 Subject: usb: core: use phy_exit during suspend if wake up is not supported If the USB controller can wake up the system (which is the case for example with the Mediatek USB3 IP) then we must not call phy_exit during suspend to ensure that the USB controller doesn't have to re-enumerate the devices during resume. However, if the USB controller cannot wake up the system (which is the case for example on various TI platforms using a dwc3 controller) then we must call phy_exit during suspend. Otherwise the PHY driver keeps the clocks enabled, which prevents the system from reaching the lowest power levels in the suspend state. Solve this by introducing two new functions in the PHY wrapper which are dedicated to the suspend and resume handling. If the controller can wake up the system the new usb_phy_roothub_suspend function will simply call usb_phy_roothub_power_off. However, if wake up is not supported by the controller it will also call usb_phy_roothub_exit. The also new usb_phy_roothub_resume function takes care of calling usb_phy_roothub_init (if the controller can't wake up the system) in addition to usb_phy_roothub_power_on. Fixes: 07dbff0ddbd86c ("usb: core: add a wrapper for the USB PHYs on the HCD") Fixes: 178a0bce05cbc1 ("usb: core: hcd: integrate the PHY wrapper into the HCD core") Reported-by: Roger Quadros Suggested-by: Roger Quadros Suggested-by: Chunfeng Yun Signed-off-by: Martin Blumenstingl Tested-by: Chunfeng Yun Reviewed-by: Roger Quadros Tested-by: Keerthy Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hcd.c | 8 +++++--- drivers/usb/core/phy.c | 35 +++++++++++++++++++++++++++++++++++ drivers/usb/core/phy.h | 5 +++++ 3 files changed, 45 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index f0e5f4d875d8..0a42c5df3c0f 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -2262,7 +2262,8 @@ int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg) hcd->state = HC_STATE_SUSPENDED; if (!PMSG_IS_AUTO(msg)) - usb_phy_roothub_power_off(hcd->phy_roothub); + usb_phy_roothub_suspend(hcd->self.sysdev, + hcd->phy_roothub); /* Did we race with a root-hub wakeup event? */ if (rhdev->do_remote_wakeup) { @@ -2302,7 +2303,8 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) } if (!PMSG_IS_AUTO(msg)) { - status = usb_phy_roothub_power_on(hcd->phy_roothub); + status = usb_phy_roothub_resume(hcd->self.sysdev, + hcd->phy_roothub); if (status) return status; } @@ -2344,7 +2346,7 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) } } else { hcd->state = old_state; - usb_phy_roothub_power_off(hcd->phy_roothub); + usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub); dev_dbg(&rhdev->dev, "bus %s fail, err %d\n", "resume", status); if (status != -ESHUTDOWN) diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c index 44f008cda7a8..a39d9bb26a4f 100644 --- a/drivers/usb/core/phy.c +++ b/drivers/usb/core/phy.c @@ -157,3 +157,38 @@ void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub) phy_power_off(roothub_entry->phy); } EXPORT_SYMBOL_GPL(usb_phy_roothub_power_off); + +int usb_phy_roothub_suspend(struct device *controller_dev, + struct usb_phy_roothub *phy_roothub) +{ + usb_phy_roothub_power_off(phy_roothub); + + /* keep the PHYs initialized so the device can wake up the system */ + if (device_may_wakeup(controller_dev)) + return 0; + + return usb_phy_roothub_exit(phy_roothub); +} +EXPORT_SYMBOL_GPL(usb_phy_roothub_suspend); + +int usb_phy_roothub_resume(struct device *controller_dev, + struct usb_phy_roothub *phy_roothub) +{ + int err; + + /* if the device can't wake up the system _exit was called */ + if (!device_may_wakeup(controller_dev)) { + err = usb_phy_roothub_init(phy_roothub); + if (err) + return err; + } + + err = usb_phy_roothub_power_on(phy_roothub); + + /* undo _init if _power_on failed */ + if (err && !device_may_wakeup(controller_dev)) + usb_phy_roothub_exit(phy_roothub); + + return err; +} +EXPORT_SYMBOL_GPL(usb_phy_roothub_resume); diff --git a/drivers/usb/core/phy.h b/drivers/usb/core/phy.h index eb31253201ad..605555901d44 100644 --- a/drivers/usb/core/phy.h +++ b/drivers/usb/core/phy.h @@ -7,3 +7,8 @@ int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub); int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub); void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub); + +int usb_phy_roothub_suspend(struct device *controller_dev, + struct usb_phy_roothub *phy_roothub); +int usb_phy_roothub_resume(struct device *controller_dev, + struct usb_phy_roothub *phy_roothub); -- cgit v1.2.3