Support system sleep with offloaded usb transfers

index b25d80f318a9..2fdafbcbe44c 100644
@@ -2582,6 +2582,76 @@ static int dwc3_resume(struct device *dev)
 	return 0;
 }
 
+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);

@@ -2599,7 +2669,12 @@ 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,
 	SET_RUNTIME_PM_OPS(dwc3_runtime_suspend, dwc3_runtime_resume,
 			dwc3_runtime_idle)

index 8dc23812b204..6e49ef1908eb 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 0c3f12daac79..e53cb4c267b3 100644
@@ -2041,6 +2041,83 @@ int usb_disable_usb2_hardware_lpm(struct usb_device *udev)
 
 #endif /* CONFIG_PM */
 
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+
+/**
+ * usb_sideband_get - increment the sb_usage_count of a USB device
+ * @udev: the USB device to increment its sb_usage_count
+ *
+ * Incrementing the sb_usage_count of a usb_device indicates that a sideband is
+ * currently using the device; that is, another entity is actively handling USB
+ * transfers. This information allows the USB driver to adjust its power
+ * management policy based on sideband activity.
+ *
+ * The caller must hold @udev's device lock.
+ *
+ * Return: 0 on success. A negative error code otherwise.
+ */
+int usb_sideband_get(struct usb_device *udev)
+{
+	if (udev->state == USB_STATE_NOTATTACHED ||
+			udev->state == USB_STATE_SUSPENDED)
+		return -EAGAIN;
+
+	refcount_inc(&udev->sb_usage_count);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(usb_sideband_get);
+
+/**
+ * usb_sideband_put - drop the sb_usage_count of a USB device
+ * @udev: the USB device to drop its sb_usage_count
+ *
+ * The inverse operation of usb_sideband_get, which drops the sb_usage_count of
+ * a USB device. This information allows the USB driver to adjust its power
+ * management policy based on sideband activity.
+ *
+ * The caller must hold @udev's device lock.
+ *
+ * Return: 0 on success. A negative error code otherwise.
+ */
+int usb_sideband_put(struct usb_device *udev)
+{
+	if (udev->state == USB_STATE_NOTATTACHED ||
+			udev->state == USB_STATE_SUSPENDED)
+		return -EAGAIN;
+
+	refcount_dec(&udev->sb_usage_count);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(usb_sideband_put);
+
+/**
+ * usb_sideband_check - check sideband activities on a USB device
+ * @udev: the USB device to check its sideband activity.
+ *
+ * Check if there are any sideband activity on the USB device right now. This
+ * information could be used for power management or other forms or resource
+ * management.
+ *
+ * Returns true on any active sideband existence, false otherwise
+ */
+bool usb_sideband_check(struct usb_device *udev)
+{
+	struct usb_device *child;
+	int port1;
+
+	usb_hub_for_each_child(udev, port1, child) {
+		if (usb_sideband_check(child))
+			return true;
+	}
+
+	return !!refcount_read(&udev->sb_usage_count);
+}
+EXPORT_SYMBOL_GPL(usb_sideband_check);
+
+#endif /* CONFIG_USB_XHCI_SIDEBAND */
+
 const struct bus_type usb_bus_type = {
 	.name =		"usb",
 	.match =	usb_device_match,

index 0b4685aad2d5..00bb00d15875 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->sb_usage_count, 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 672d8fc2abdb..c5586532cd12 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.
+ * @sb_usage_count: number of active sideband accessing 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 sb_usage_count;
+#endif
 };
 
 #define to_usb_device(__dev)	container_of_const(__dev, struct usb_device, dev)

@@ -837,6 +842,21 @@ static inline void usb_mark_last_busy(struct usb_device *udev)
 { }
 #endif
 
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+extern int usb_sideband_get(struct usb_device *udev);
+extern int usb_sideband_put(struct usb_device *udev);
+extern bool usb_sideband_check(struct usb_device *udev);
+
+#else
+
+static inline int usb_sideband_get(struct usb_device *udev)
+{ return 0; }
+static inline int usb_sideband_put(struct usb_device *udev)
+{ return 0; }
+static inline bool usb_sideband_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 1ff7d901fede..6aca6c69bf74 100644
@@ -2595,6 +2595,10 @@ struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
 #endif
 
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+	refcount_set(&hcd->sb_usage_count, 0);
+#endif
+
 	INIT_WORK(&hcd->died_work, hcd_died_work);
 
 	hcd->driver = driver;

98 lines not on this page · raw message

index ac95e7c89df5..9867c178d188 100644
@@ -85,6 +85,12 @@ struct usb_hcd {
 #ifdef CONFIG_PM
 	struct work_struct	wakeup_work;	/* for remote wakeup */
 #endif
+
+#ifdef CONFIG_USB_XHCI_SIDEBAND
+	/* Number of active sideband accessing the host controller. */
+	refcount_t		sb_usage_count;
+#endif
+
 	struct work_struct	died_work;	/* for when the device dies */
 
 	/*

index f0223c5535e0..4850fc826e00 100644
@@ -12,6 +12,7 @@
 
 #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 */
 

@@ -57,6 +58,10 @@ xhci_sideband_get_endpoint_buffer(struct xhci_sideband *sb,
 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 e53cb4c267b3..e5bb26e6c71a 100644
@@ -1583,6 +1583,11 @@ int usb_suspend(struct device *dev, pm_message_t msg)
 	struct usb_device	*udev = to_usb_device(dev);
 	int r;
 
+	if (msg.event == PM_EVENT_SUSPEND && usb_sideband_check(udev)) {
+		dev_dbg(dev, "device accessed via sideband\n");
+		return 0;
+	}
+
 	unbind_no_pm_drivers_interfaces(udev);
 
 	/* From now on we are sure all drivers support suspend/resume

@@ -1619,6 +1624,11 @@ int usb_resume(struct device *dev, pm_message_t msg)
 	struct usb_device	*udev = to_usb_device(dev);
 	int			status;
 
+	if (msg.event == PM_EVENT_RESUME && usb_sideband_check(udev)) {
+		dev_dbg(dev, "device accessed via sideband\n");
+		return 0;
+	}
+
 	/* For all calls, take the device back to full power and
 	 * tell the PM core in case it was autosuspended previously.
 	 * Unbind the interfaces that will need rebinding later,

index 2fdafbcbe44c..d85c68d5eba4 100644
@@ -2550,8 +2550,18 @@ static int dwc3_runtime_idle(struct device *dev)
 static int dwc3_suspend(struct device *dev)
 {
 	struct dwc3	*dwc = dev_get_drvdata(dev);
+	struct platform_device *xhci = dwc->xhci;
+	struct usb_hcd  *hcd;
 	int		ret;
 
+	if (xhci) {
+		hcd = dev_get_drvdata(&xhci->dev);
+		if (xhci_sideband_check(hcd)) {
+			dev_dbg(dev, "device accessed via sideband\n");
+			return 0;
+		}
+	}
+
 	ret = dwc3_suspend_common(dwc, PMSG_SUSPEND);
 	if (ret)
 		return ret;

@@ -2564,8 +2574,18 @@ static int dwc3_suspend(struct device *dev)
 static int dwc3_resume(struct device *dev)
 {
 	struct dwc3	*dwc = dev_get_drvdata(dev);
+	struct platform_device *xhci = dwc->xhci;
+	struct usb_hcd  *hcd;
 	int		ret;
 
+	if (xhci) {
+		hcd = dev_get_drvdata(&xhci->dev);
+		if (xhci_sideband_check(hcd)) {
+			dev_dbg(dev, "device accessed via sideband\n");
+			return 0;
+		}
+	}
+
 	pinctrl_pm_select_default_state(dev);
 
 	pm_runtime_disable(dev);

index 80047d0df179..a585e9d80e59 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 6e49ef1908eb..5fdbdf0c7f1a 100644
@@ -456,6 +456,11 @@ static int xhci_plat_suspend_common(struct device *dev, struct pm_message pmsg)
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
 	int ret;
 
+	if (pmsg.event == PM_EVENT_SUSPEND && xhci_sideband_check(hcd)) {
+		dev_dbg(dev, "device accessed via sideband\n");
+		return 0;
+	}
+
 	if (pm_runtime_suspended(dev))
 		pm_runtime_resume(dev);
 

@@ -499,6 +504,11 @@ static int xhci_plat_resume_common(struct device *dev, struct pm_message pmsg)
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
 	int ret;
 
+	if (pmsg.event == PM_EVENT_RESUME && xhci_sideband_check(hcd)) {
+		dev_dbg(dev, "device accessed via sideband\n");
+		return 0;
+	}
+
 	if (!device_may_wakeup(dev) && (xhci->quirks & XHCI_SUSPEND_RESUME_CLKS)) {
 		ret = clk_prepare_enable(xhci->clk);
 		if (ret)

index 9867c178d188..b22d25ccdf7c 100644
@@ -772,6 +772,13 @@ 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 */