4 files changed, 37 insertions, 2 deletions

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 770d1e91183c..3e1215f7a9a0 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -68,6 +68,12 @@
  */
 #define USB_SHORT_SET_ADDRESS_REQ_TIMEOUT	500  /* ms */
 
+/*
+ * Give SS hubs 200ms time after wake to train downstream links before
+ * assuming no port activity and allowing hub to runtime suspend back.
+ */
+#define USB_SS_PORT_U0_WAKE_TIME	200  /* ms */
+
 /* Protect struct usb_device->state and ->children members
  * Note: Both are also protected by ->dev.sem, except that ->state can
  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
@@ -1095,6 +1101,7 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 			goto init2;
 		goto init3;
 	}
+
 	hub_get(hub);
 
 	/* The superspeed hub except for root hub has to use Hub Depth
@@ -1343,6 +1350,17 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 		device_unlock(&hdev->dev);
 	}
 
+	if (type == HUB_RESUME && hub_is_superspeed(hub->hdev)) {
+		/* give usb3 downstream links training time after hub resume */
+		usb_autopm_get_interface_no_resume(
+			to_usb_interface(hub->intfdev));
+
+		queue_delayed_work(system_power_efficient_wq,
+				   &hub->post_resume_work,
+				   msecs_to_jiffies(USB_SS_PORT_U0_WAKE_TIME));
+		return;
+	}
+
 	hub_put(hub);
 }
 
@@ -1361,6 +1379,14 @@ static void hub_init_func3(struct work_struct *ws)
 	hub_activate(hub, HUB_INIT3);
 }
 
+static void hub_post_resume(struct work_struct *ws)
+{
+	struct usb_hub *hub = container_of(ws, struct usb_hub, post_resume_work.work);
+
+	usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
+	hub_put(hub);
+}
+
 enum hub_quiescing_type {
 	HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
 };
@@ -1386,6 +1412,7 @@ static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
 
 	/* Stop hub_wq and related activity */
 	timer_delete_sync(&hub->irq_urb_retry);
+	flush_delayed_work(&hub->post_resume_work);
 	usb_kill_urb(hub->urb);
 	if (hub->has_indicators)
 		cancel_delayed_work_sync(&hub->leds);
@@ -1944,6 +1971,7 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 	hub->hdev = hdev;
 	INIT_DELAYED_WORK(&hub->leds, led_work);
 	INIT_DELAYED_WORK(&hub->init_work, NULL);
+	INIT_DELAYED_WORK(&hub->post_resume_work, hub_post_resume);
 	INIT_WORK(&hub->events, hub_event);
 	INIT_LIST_HEAD(&hub->onboard_devs);
 	spin_lock_init(&hub->irq_urb_lock);
@@ -2337,6 +2365,9 @@ void usb_disconnect(struct usb_device **pdev)
 	usb_remove_ep_devs(&udev->ep0);
 	usb_unlock_device(udev);
 
+	if (udev->usb4_link)
+		device_link_del(udev->usb4_link);
+
 	/* Unregister the device.  The device driver is responsible
 	 * for de-configuring the device and invoking the remove-device
 	 * notifier chain (used by usbfs and possibly others).
diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index e6ae73f8a95d..9ebc5ef54a32 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h
@@ -70,6 +70,7 @@ struct usb_hub {
 	u8			indicator[USB_MAXCHILDREN];
 	struct delayed_work	leds;
 	struct delayed_work	init_work;
+	struct delayed_work	post_resume_work;
 	struct work_struct      events;
 	spinlock_t		irq_urb_lock;
 	struct timer_list	irq_urb_retry;
diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
index 53d68d20fb62..0cf94c7a2c9c 100644
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -227,7 +227,8 @@ static const struct usb_device_id usb_quirk_list[] = {
 	{ USB_DEVICE(0x046a, 0x0023), .driver_info = USB_QUIRK_RESET_RESUME },
 
 	/* Logitech HD Webcam C270 */
-	{ USB_DEVICE(0x046d, 0x0825), .driver_info = USB_QUIRK_RESET_RESUME },
+	{ USB_DEVICE(0x046d, 0x0825), .driver_info = USB_QUIRK_RESET_RESUME |
+		USB_QUIRK_NO_LPM},
 
 	/* Logitech HD Pro Webcams C920, C920-C, C922, C925e and C930e */
 	{ USB_DEVICE(0x046d, 0x082d), .driver_info = USB_QUIRK_DELAY_INIT },
diff --git a/drivers/usb/core/usb-acpi.c b/drivers/usb/core/usb-acpi.c
index ea1ce8beb0cb..489dbdc96f94 100644
--- a/drivers/usb/core/usb-acpi.c
+++ b/drivers/usb/core/usb-acpi.c
@@ -157,7 +157,7 @@ EXPORT_SYMBOL_GPL(usb_acpi_set_power_state);
  */
 static int usb_acpi_add_usb4_devlink(struct usb_device *udev)
 {
-	const struct device_link *link;
+	struct device_link *link;
 	struct usb_port *port_dev;
 	struct usb_hub *hub;
 
@@ -188,6 +188,8 @@ static int usb_acpi_add_usb4_devlink(struct usb_device *udev)
 	dev_dbg(&port_dev->dev, "Created device link from %s to %s\n",
 		dev_name(&port_dev->child->dev), dev_name(nhi_fwnode->dev));
 
+	udev->usb4_link = link;
+
 	return 0;
 }