1 files changed, 49 insertions, 12 deletions

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 522f766a7d07..62084335a608 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1035,10 +1035,20 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 	unsigned delay;
 
 	/* Continue a partial initialization */
-	if (type == HUB_INIT2)
-		goto init2;
-	if (type == HUB_INIT3)
+	if (type == HUB_INIT2 || type == HUB_INIT3) {
+		device_lock(hub->intfdev);
+
+		/* Was the hub disconnected while we were waiting? */
+		if (hub->disconnected) {
+			device_unlock(hub->intfdev);
+			kref_put(&hub->kref, hub_release);
+			return;
+		}
+		if (type == HUB_INIT2)
+			goto init2;
 		goto init3;
+	}
+	kref_get(&hub->kref);
 
 	/* The superspeed hub except for root hub has to use Hub Depth
 	 * value as an offset into the route string to locate the bits
@@ -1236,6 +1246,7 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 			queue_delayed_work(system_power_efficient_wq,
 					&hub->init_work,
 					msecs_to_jiffies(delay));
+			device_unlock(hub->intfdev);
 			return;		/* Continues at init3: below */
 		} else {
 			msleep(delay);
@@ -1257,6 +1268,11 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 	/* Allow autosuspend if it was suppressed */
 	if (type <= HUB_INIT3)
 		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
+
+	if (type == HUB_INIT2 || type == HUB_INIT3)
+		device_unlock(hub->intfdev);
+
+	kref_put(&hub->kref, hub_release);
 }
 
 /* Implement the continuations for the delays above */
@@ -3870,17 +3886,30 @@ static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
 		return;
 	}
 
-	if (usb_set_lpm_timeout(udev, state, timeout))
+	if (usb_set_lpm_timeout(udev, state, timeout)) {
 		/* If we can't set the parent hub U1/U2 timeout,
 		 * device-initiated LPM won't be allowed either, so let the xHCI
 		 * host know that this link state won't be enabled.
 		 */
 		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
+	} else {
+		/* Only a configured device will accept the Set Feature
+		 * U1/U2_ENABLE
+		 */
+		if (udev->actconfig)
+			usb_set_device_initiated_lpm(udev, state, true);
 
-	/* Only a configured device will accept the Set Feature U1/U2_ENABLE */
-	else if (udev->actconfig)
-		usb_set_device_initiated_lpm(udev, state, true);
-
+		/* As soon as usb_set_lpm_timeout(timeout) returns 0, the
+		 * hub-initiated LPM is enabled. Thus, LPM is enabled no
+		 * matter the result of usb_set_device_initiated_lpm().
+		 * The only difference is whether device is able to initiate
+		 * LPM.
+		 */
+		if (state == USB3_LPM_U1)
+			udev->usb3_lpm_u1_enabled = 1;
+		else if (state == USB3_LPM_U2)
+			udev->usb3_lpm_u2_enabled = 1;
+	}
 }
 
 /*
@@ -3920,6 +3949,18 @@ static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
 		dev_warn(&udev->dev, "Could not disable xHCI %s timeout, "
 				"bus schedule bandwidth may be impacted.\n",
 				usb3_lpm_names[state]);
+
+	/* As soon as usb_set_lpm_timeout(0) return 0, hub initiated LPM
+	 * is disabled. Hub will disallows link to enter U1/U2 as well,
+	 * even device is initiating LPM. Hence LPM is disabled if hub LPM
+	 * timeout set to 0, no matter device-initiated LPM is disabled or
+	 * not.
+	 */
+	if (state == USB3_LPM_U1)
+		udev->usb3_lpm_u1_enabled = 0;
+	else if (state == USB3_LPM_U2)
+		udev->usb3_lpm_u2_enabled = 0;
+
 	return 0;
 }
 
@@ -3954,8 +3995,6 @@ int usb_disable_lpm(struct usb_device *udev)
 	if (usb_disable_link_state(hcd, udev, USB3_LPM_U2))
 		goto enable_lpm;
 
-	udev->usb3_lpm_enabled = 0;
-
 	return 0;
 
 enable_lpm:
@@ -4013,8 +4052,6 @@ void usb_enable_lpm(struct usb_device *udev)
 
 	usb_enable_link_state(hcd, udev, USB3_LPM_U1);
 	usb_enable_link_state(hcd, udev, USB3_LPM_U2);
-
-	udev->usb3_lpm_enabled = 1;
 }
 EXPORT_SYMBOL_GPL(usb_enable_lpm);