Support system sleep with offloaded usb transfers

index 6c960ff30c92..0735881d4650 100644
@@ -2632,6 +2632,76 @@ static int dwc3_resume(struct device *dev)
 	return ret;
 }
 
+static int dwc3_freeze(struct device *dev)
+{
+	struct dwc3	*dwc = dev_get_drvdata(dev);
+	int		ret;
+
+	ret = dwc3_suspend_common(dwc, PMSG_FREEZE);
+	if (ret)
+		return ret;
+
+	pinctrl_pm_select_sleep_state(dev);
+
+	return 0;
+}
+
+static int dwc3_thaw(struct device *dev)
+{
+	struct dwc3	*dwc = dev_get_drvdata(dev);
+	int		ret;
+
+	pinctrl_pm_select_default_state(dev);
+
+	pm_runtime_disable(dev);
+	pm_runtime_set_active(dev);
+
+	ret = dwc3_resume_common(dwc, PMSG_THAW);
+	if (ret) {
+		pm_runtime_set_suspended(dev);
+		return ret;
+	}
+
+	pm_runtime_enable(dev);
+
+	return 0;
+}
+
+static int dwc3_poweroff(struct device *dev)
+{
+	struct dwc3	*dwc = dev_get_drvdata(dev);
+	int		ret;
+
+	ret = dwc3_suspend_common(dwc, PMSG_HIBERNATE);
+	if (ret)
+		return ret;
+
+	pinctrl_pm_select_sleep_state(dev);
+
+	return 0;
+}
+
+static int dwc3_restore(struct device *dev)
+{
+	struct dwc3	*dwc = dev_get_drvdata(dev);
+	int		ret;
+
+	pinctrl_pm_select_default_state(dev);
+
+	pm_runtime_disable(dev);
+	pm_runtime_set_active(dev);
+
+	ret = dwc3_resume_common(dwc, PMSG_RESTORE);
+	if (ret) {
+		pm_runtime_set_suspended(dev);
+		return ret;
+	}
+
+	pm_runtime_enable(dev);
+
+	return 0;
+}
+
 static void dwc3_complete(struct device *dev)
 {
 	struct dwc3	*dwc = dev_get_drvdata(dev);

@@ -2649,7 +2719,12 @@ static void dwc3_complete(struct device *dev)
 #endif /* CONFIG_PM_SLEEP */
 
 static const struct dev_pm_ops dwc3_dev_pm_ops = {
-	SET_SYSTEM_SLEEP_PM_OPS(dwc3_suspend, dwc3_resume)
+	.suspend = pm_sleep_ptr(dwc3_suspend),
+	.resume = pm_sleep_ptr(dwc3_resume),
+	.freeze = pm_sleep_ptr(dwc3_freeze),
+	.thaw = pm_sleep_ptr(dwc3_thaw),
+	.poweroff = pm_sleep_ptr(dwc3_poweroff),
+	.restore = pm_sleep_ptr(dwc3_restore),
 	.complete = dwc3_complete,
 
 	/*

index 3acdbbd9aea3..b676d4dbcec1 100644
@@ -450,7 +450,7 @@ void xhci_plat_remove(struct platform_device *dev)
 }
 EXPORT_SYMBOL_GPL(xhci_plat_remove);
 
-static int xhci_plat_suspend(struct device *dev)
+static int xhci_plat_suspend_common(struct device *dev, struct pm_message pmsg)
 {
 	struct usb_hcd	*hcd = dev_get_drvdata(dev);
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);

@@ -478,6 +478,21 @@ static int xhci_plat_suspend(struct device *dev)
 	return 0;
 }
 
+static int xhci_plat_suspend(struct device *dev)
+{
+	return xhci_plat_suspend_common(dev, PMSG_SUSPEND);
+}
+
+static int xhci_plat_freeze(struct device *dev)
+{
+	return xhci_plat_suspend_common(dev, PMSG_FREEZE);
+}
+
+static int xhci_plat_poweroff(struct device *dev)
+{
+	return xhci_plat_suspend_common(dev, PMSG_HIBERNATE);
+}
+
 static int xhci_plat_resume_common(struct device *dev, struct pm_message pmsg)
 {
 	struct usb_hcd	*hcd = dev_get_drvdata(dev);

@@ -524,6 +539,11 @@ static int xhci_plat_resume(struct device *dev)
 	return xhci_plat_resume_common(dev, PMSG_RESUME);
 }
 
+static int xhci_plat_thaw(struct device *dev)
+{
+	return xhci_plat_resume_common(dev, PMSG_THAW);
+}
+
 static int xhci_plat_restore(struct device *dev)
 {
 	return xhci_plat_resume_common(dev, PMSG_RESTORE);

@@ -553,9 +573,9 @@ static int __maybe_unused xhci_plat_runtime_resume(struct device *dev)
 const struct dev_pm_ops xhci_plat_pm_ops = {
 	.suspend = pm_sleep_ptr(xhci_plat_suspend),
 	.resume = pm_sleep_ptr(xhci_plat_resume),
-	.freeze = pm_sleep_ptr(xhci_plat_suspend),
-	.thaw = pm_sleep_ptr(xhci_plat_resume),
-	.poweroff = pm_sleep_ptr(xhci_plat_suspend),
+	.freeze = pm_sleep_ptr(xhci_plat_freeze),
+	.thaw = pm_sleep_ptr(xhci_plat_thaw),
+	.poweroff = pm_sleep_ptr(xhci_plat_poweroff),
 	.restore = pm_sleep_ptr(xhci_plat_restore),
 
 	SET_RUNTIME_PM_OPS(xhci_plat_runtime_suspend,

index f203fdbfb6f6..01f6287cf73f 100644
@@ -2037,6 +2037,114 @@ int usb_disable_usb2_hardware_lpm(struct usb_device *udev)
 
 #endif /* CONFIG_PM */
 
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+
+/**
+ * usb_offload_get - increment the offload_usage of a USB device
+ * @udev: the USB device to increment its offload_usage
+ *
+ * Incrementing the offload_usage of a usb_device indicates that offload is
+ * enabled on this usb_device; that is, another entity is actively handling USB
+ * transfers. This information allows the USB driver to adjust its power
+ * management policy based on offload activity.
+ *
+ * The caller must hold @udev's device lock.
+ *
+ * Return: 0 on success. A negative error code otherwise.
+ */
+int usb_offload_get(struct usb_device *udev)
+{
+	int ret;
+
+	if (udev->state == USB_STATE_NOTATTACHED ||
+			udev->state == USB_STATE_SUSPENDED)
+		return -EAGAIN;
+
+	/*
+	 * offload_usage could only be modified when the device is active, since
+	 * it will alter the suspend flow of the device.
+	 */
+	ret = pm_runtime_get_sync(&udev->dev);
+
+	if (ret < 0)
+		return ret;
+
+	refcount_inc(&udev->offload_usage);
+	pm_runtime_put_sync(&udev->dev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(usb_offload_get);
+
+/**
+ * usb_offload_put - drop the offload_usage of a USB device
+ * @udev: the USB device to drop its offload_usage
+ *
+ * The inverse operation of usb_offload_get, which drops the offload_usage of
+ * a USB device. This information allows the USB driver to adjust its power
+ * management policy based on offload activity.
+ *
+ * The caller must hold @udev's device lock.
+ *
+ * Return: 0 on success. A negative error code otherwise.
+ */
+int usb_offload_put(struct usb_device *udev)
+{
+	int ret;
+
+	if (udev->state == USB_STATE_NOTATTACHED ||
+			udev->state == USB_STATE_SUSPENDED)
+		return -EAGAIN;
+
+	/*
+	 * offload_usage could only be modified when the device is active, since
+	 * it will alter the suspend flow of the device.
+	 */
+	ret = pm_runtime_get_sync(&udev->dev);
+
+	if (ret < 0)
+		return ret;
+
+	/* Drop the count when it wasn't 0, ignore the operation otherwise. */
+	ret = refcount_add_not_zero(-1, &udev->offload_usage);
+	pm_runtime_put_sync(&udev->dev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(usb_offload_put);
+
+/**
+ * usb_offload_check - check offload activities on a USB device
+ * @udev: the USB device to check its offload activity.
+ *
+ * Check if there are any offload activity on the USB device right now. This
+ * information could be used for power management or other forms of resource
+ * management.
+ *
+ * The caller must hold @udev's device lock.
+ *
+ * Returns true on any offload activity, false otherwise.
+ */
+bool usb_offload_check(struct usb_device *udev)
+{
+	struct usb_device *child;
+	bool active;
+	int port1;
+
+	usb_hub_for_each_child(udev, port1, child) {
+		device_lock(&child->dev);
+		active = usb_offload_check(child);
+		device_unlock(&child->dev);
+		if (active)
+			return true;
+	}
+
+	return !!refcount_read(&udev->offload_usage);
+}
+EXPORT_SYMBOL_GPL(usb_offload_check);
+
+#endif /* CONFIG_USB_XHCI_SIDEBAND */
+
 const struct bus_type usb_bus_type = {
 	.name =		"usb",
 	.match =	usb_device_match,

index 0b4685aad2d5..888ab599fd06 100644
@@ -672,6 +672,10 @@ struct usb_device *usb_alloc_dev(struct usb_device *parent,
 	dev->lpm_disable_count = 1;
 	atomic_set(&dev->urbnum, 0);
 
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+	refcount_set(&dev->offload_usage, 0);
+#endif
+
 	INIT_LIST_HEAD(&dev->ep0.urb_list);
 	dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
 	dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;

index cfa8005e24f9..9b3f630e763e 100644
@@ -645,6 +645,7 @@ struct usb3_lpm_parameters {
  *	parent->hub_delay + wHubDelay + tTPTransmissionDelay (40ns)
  *	Will be used as wValue for SetIsochDelay requests.
  * @use_generic_driver: ask driver core to reprobe using the generic driver.
+ * @offload_usage: number of offload activities happening on this usb device.
  *
  * Notes:
  * Usbcore drivers should not set usbdev->state directly.  Instead use

@@ -731,6 +732,10 @@ struct usb_device {
 
 	u16 hub_delay;
 	unsigned use_generic_driver:1;
+
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+	refcount_t offload_usage;
+#endif
 };
 
 #define to_usb_device(__dev)	container_of_const(__dev, struct usb_device, dev)

@@ -837,6 +842,20 @@ static inline void usb_mark_last_busy(struct usb_device *udev)
 { }
 #endif
 
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+extern int usb_offload_get(struct usb_device *udev);
+extern int usb_offload_put(struct usb_device *udev);
+extern bool usb_offload_check(struct usb_device *udev);
+#else
+
+static inline int usb_offload_get(struct usb_device *udev)
+{ return 0; }
+static inline int usb_offload_put(struct usb_device *udev)
+{ return 0; }
+static inline bool usb_offload_check(struct usb_device *udev)
+{ return false; }
+#endif
+
 extern int usb_disable_lpm(struct usb_device *udev);
 extern void usb_enable_lpm(struct usb_device *udev);
 /* Same as above, but these functions lock/unlock the bandwidth_mutex. */

index ffa6f1b825ff..d4931315dcf4 100644
@@ -358,6 +358,88 @@ xhci_sideband_interrupter_id(struct xhci_sideband *sb)
 }
 EXPORT_SYMBOL_GPL(xhci_sideband_interrupter_id);
 
+/**
+ * xhci_sideband_get - record a new active sideband instance
+ * @sb: sideband instance for this usb device
+ *
+ * An active sideband indicates that another entity is currently using the host
+ * controller. Inform the usb_device associated with this sideband instance via
+ * usb_offload_get(). This allows the corresponding drivers to dynamically
+ * adjust power management actions based on current sideband activities.
+ *
+ * Returns 0 on success, negative error otherwise.
+ */
+int xhci_sideband_get(struct xhci_sideband *sb)
+{
+	struct usb_device *udev;
+	struct usb_hcd *hcd;
+	int ret = 0;
+
+	if (!sb || !sb->xhci)
+		return -ENODEV;
+
+	hcd = xhci_to_hcd(sb->xhci);
+	udev = sb->vdev->udev;
+	device_lock(&udev->dev);
+	ret = usb_offload_get(udev);
+	device_unlock(&udev->dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(xhci_sideband_get);
+
+/**
+ * xhci_sideband_put - record a deactivated sideband instance
+ * @sb: sideband instance for this usb device
+ *
+ * The inverse operation of xhci_sideband_get, which informs the associated
+ * usb_device via usb_offload_put(). This allows the corresponding drivers to
+ * dynamically adjust power management actions based on sideband activities.
+ *
+ * Returns 0 on success, negative error otherwise.
+ */
+int xhci_sideband_put(struct xhci_sideband *sb)
+{
+	struct usb_device *udev;
+	struct usb_hcd *hcd;
+	int ret = 0;
+
+	if (!sb || !sb->xhci)
+		return -ENODEV;
+
+	hcd = xhci_to_hcd(sb->xhci);
+	udev = sb->vdev->udev;
+	device_lock(&udev->dev);
+	ret = usb_offload_put(udev);
+	device_unlock(&udev->dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(xhci_sideband_put);
+
+/**
+ * xhci_sideband_check - check the existence of active sidebands
+ * @hcd: the host controller driver associated with the target host controller
+ *
+ * Allow other drivers, such as usb controller driver, to check if there are
+ * any sideband activity on the host controller. This information could be used
+ * for power management or other forms of resource management.
+ *
+ * Returns true on any active sideband existence, false otherwise.
+ */
+bool xhci_sideband_check(struct usb_hcd *hcd)
+{
+	struct usb_device *udev = hcd->self.root_hub;
+	bool active;
+
+	device_lock(&udev->dev);
+	active = usb_offload_check(udev);
+	device_unlock(&udev->dev);
+
+	return active;
+}
+EXPORT_SYMBOL_GPL(xhci_sideband_check);
+
 /**
  * xhci_sideband_register - register a sideband for a usb device
  * @intf: usb interface associated with the sideband device

index 72aa17eb068d..6de1d9c161a1 100644
@@ -11,6 +11,7 @@
 
 #include <linux/scatterlist.h>
 #include <linux/usb.h>
+#include <linux/usb/hcd.h>
 
 #define	EP_CTX_PER_DEV		31	/* FIXME defined twice, from xhci.h */
 

@@ -82,6 +83,11 @@ xhci_sideband_get_endpoint_buffer(struct xhci_sideband *sb,
 				  struct usb_host_endpoint *host_ep);
 struct sg_table *
 xhci_sideband_get_event_buffer(struct xhci_sideband *sb);
+
+int xhci_sideband_get(struct xhci_sideband *sb);
+int xhci_sideband_put(struct xhci_sideband *sb);
+bool xhci_sideband_check(struct usb_hcd *hcd);
+
 int
 xhci_sideband_create_interrupter(struct xhci_sideband *sb, int num_seg,
 				 bool ip_autoclear, u32 imod_interval, int intr_num);

index 01f6287cf73f..06f9809e2d92 100644
@@ -1413,19 +1413,32 @@ static int usb_resume_interface(struct usb_device *udev,
  */
 static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
 {
-	int			status = 0;
-	int			i = 0, n = 0;
-	struct usb_interface	*intf;
+	int			 status = 0;
+	int			 i = 0, n = 0;
+	bool			 offload = false;
+	struct usb_interface	 *intf;
+	struct usb_host_endpoint *ep;
 
 	if (udev->state == USB_STATE_NOTATTACHED ||
 			udev->state == USB_STATE_SUSPENDED)
 		goto done;
 
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+	if (msg.event == PM_EVENT_SUSPEND && usb_offload_check(udev)) {
+		dev_dbg(&udev->dev, "device offload active.\n");
+		offload = true;
+	}
+#endif
+
 	/* Suspend all the interfaces and then udev itself */
 	if (udev->actconfig) {
 		n = udev->actconfig->desc.bNumInterfaces;
 		for (i = n - 1; i >= 0; --i) {
 			intf = udev->actconfig->interface[i];
+			if (offload && intf->needs_remote_wakeup) {
+				dev_dbg(&intf->dev, "interface stays active on an offloaded device\n");
+				continue;
+			}
 			status = usb_suspend_interface(udev, intf, msg);
 
 			/* Ignore errors during system sleep transitions */

@@ -1436,7 +1449,8 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
 		}
 	}
 	if (status == 0) {
-		status = usb_suspend_device(udev, msg);
+		if (!offload)
+			status = usb_suspend_device(udev, msg);
 
 		/*
 		 * Ignore errors from non-root-hub devices during

@@ -1482,8 +1496,19 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
 	} else {
 		udev->can_submit = 0;
 		for (i = 0; i < 16; ++i) {
-			usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
-			usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
+			if (udev->ep_out[i]) {
+				ep = udev->ep_out[i];
+				intf = to_usb_interface(ep->ep_dev->dev.parent);
+				if (!(offload && intf->needs_remote_wakeup))
+					usb_hcd_flush_endpoint(udev, ep);
+			}
+
+			if (udev->ep_in[i]) {
+				ep = udev->ep_in[i];
+				intf = to_usb_interface(ep->ep_dev->dev.parent);
+				if (!(offload && intf->needs_remote_wakeup))
+					usb_hcd_flush_endpoint(udev, ep);
+			}
 		}
 	}
 

index e48399401608..658ef39ebcd1 100644
@@ -18,14 +18,6 @@
 #include <linux/usb.h>
 #include "usb.h"
 
-struct ep_device {
-	struct usb_endpoint_descriptor *desc;
-	struct usb_device *udev;
-	struct device dev;
-};
-#define to_ep_device(_dev) \
-	container_of(_dev, struct ep_device, dev)
-
 struct ep_attribute {
 	struct attribute attr;
 	ssize_t (*show)(struct usb_device *,

index 0735881d4650..793fbc030fc4 100644
@@ -2602,8 +2602,22 @@ static int dwc3_runtime_idle(struct device *dev)
 static int dwc3_suspend(struct device *dev)
 {
 	struct dwc3	*dwc = dev_get_drvdata(dev);
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+	struct platform_device *xhci = dwc->xhci;
+	struct usb_hcd  *hcd;
+#endif
 	int		ret;
 
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+	if (xhci) {
+		hcd = dev_get_drvdata(&xhci->dev);
+		if (xhci_sideband_check(hcd)) {
+			dev_dbg(dev, "sideband instance active.\n");
+			return 0;
+		}
+	}
+#endif
+
 	ret = dwc3_suspend_common(dwc, PMSG_SUSPEND);
 	if (ret)
 		return ret;

@@ -2616,8 +2630,22 @@ static int dwc3_suspend(struct device *dev)
 static int dwc3_resume(struct device *dev)
 {
 	struct dwc3	*dwc = dev_get_drvdata(dev);
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+	struct platform_device *xhci = dwc->xhci;
+	struct usb_hcd  *hcd;
+#endif
 	int		ret = 0;
 
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+	if (xhci) {
+		hcd = dev_get_drvdata(&xhci->dev);
+		if (xhci_sideband_check(hcd)) {
+			dev_dbg(dev, "sideband instance active.\n");
+			return 0;
+		}
+	}
+#endif
+
 	pinctrl_pm_select_default_state(dev);
 
 	pm_runtime_disable(dev);

index 0b6a07202609..57c3e768cdac 100644
@@ -26,6 +26,7 @@
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
 #include <linux/usb/otg.h>
+#include <linux/usb/hcd.h>
 #include <linux/usb/role.h>
 #include <linux/ulpi/interface.h>
 

index b676d4dbcec1..9e01450328d7 100644
@@ -456,6 +456,13 @@ static int xhci_plat_suspend_common(struct device *dev, struct pm_message pmsg)
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
 	int ret;
 
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+	if (pmsg.event == PM_EVENT_SUSPEND && xhci_sideband_check(hcd)) {
+		dev_dbg(dev, "sideband instance active.\n");
+		return 0;
+	}
+#endif
+
 	if (pm_runtime_suspended(dev))
 		pm_runtime_resume(dev);
 

@@ -499,6 +506,13 @@ static int xhci_plat_resume_common(struct device *dev, struct pm_message pmsg)
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
 	int ret;
 
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+	if (pmsg.event == PM_EVENT_RESUME && xhci_sideband_check(hcd)) {
+		dev_dbg(dev, "sideband instance active.\n");
+		return 0;
+	}
+#endif
+
 	if (!device_may_wakeup(dev) && (xhci->quirks & XHCI_SUSPEND_RESUME_CLKS)) {
 		ret = clk_prepare_enable(xhci->clk);
 		if (ret)

index 9b3f630e763e..c4ff11ad14d5 100644
@@ -44,7 +44,13 @@ struct usb_driver;
  * Devices may also have class-specific or vendor-specific descriptors.
  */
 
-struct ep_device;
+struct ep_device {
+	struct usb_endpoint_descriptor *desc;
+	struct usb_device *udev;
+	struct device dev;
+};
+#define to_ep_device(_dev) \
+	container_of(_dev, struct ep_device, dev)
 
 /**
  * struct usb_host_endpoint - host-side endpoint descriptor and queue

index ac95e7c89df5..a9577da6ecff 100644
@@ -766,6 +766,13 @@ extern struct rw_semaphore ehci_cf_port_reset_rwsem;
 #define USB_EHCI_LOADED		2
 extern unsigned long usb_hcds_loaded;
 
+#if IS_ENABLED(CONFIG_USB_XHCI_SIDEBAND)
+extern bool xhci_sideband_check(struct usb_hcd *hcd);
+#else
+static inline bool xhci_sideband_check(struct usb_hcd *hcd)
+{ return false; }
+#endif
+
 #endif /* __KERNEL__ */
 
 #endif /* __USB_CORE_HCD_H */

index 7dd7e51109df..7928df8df075 100644
@@ -1619,8 +1619,11 @@ static void handle_uaudio_stream_req(struct qmi_handle *handle,
 			mutex_lock(&chip->mutex);
 			subs->opened = 0;
 			mutex_unlock(&chip->mutex);
+		} else {
+			xhci_sideband_get(uadev[pcm_card_num].si);
 		}
 	} else {
+		xhci_sideband_put(uadev[pcm_card_num].si);
 		info = &uadev[pcm_card_num].info[info_idx];
 		if (info->data_ep_pipe) {
 			ep = usb_pipe_endpoint(uadev[pcm_card_num].udev,