Merge tag 'for-usb-next-2012-02-14' of git://git.kernel.org/pub/scm/linux/kernel/git/sarah/xhci into usb-next

Support for USB 3.0 hub suspend.

This patchset adds support for suspending external USB 3.0 hubs, and fixes the
USB 3.0 device remote wakeup enabling.  Hubs are the only USB 3.0 devices on
the market right now that do remote wakeup, and they will only send a remote
wakeup if they are placed into suspend, so it's not necessary to backport this
patchset to stable kernels.

1 files changed, 115 insertions, 47 deletions

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 2d773cbe191cd..d4f062472796d 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -62,6 +62,8 @@ struct usb_hub {
 							resumed */
 	unsigned long		removed_bits[1]; /* ports with a "removed"
 							device present */
+	unsigned long		wakeup_bits[1];	/* ports that have signaled
+							remote wakeup */
 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
 #error event_bits[] is too short!
 #endif
@@ -411,6 +413,29 @@ void usb_kick_khubd(struct usb_device *hdev)
 		kick_khubd(hub);
 }
 
+/*
+ * Let the USB core know that a USB 3.0 device has sent a Function Wake Device
+ * Notification, which indicates it had initiated remote wakeup.
+ *
+ * USB 3.0 hubs do not report the port link state change from U3 to U0 when the
+ * device initiates resume, so the USB core will not receive notice of the
+ * resume through the normal hub interrupt URB.
+ */
+void usb_wakeup_notification(struct usb_device *hdev,
+		unsigned int portnum)
+{
+	struct usb_hub *hub;
+
+	if (!hdev)
+		return;
+
+	hub = hdev_to_hub(hdev);
+	if (hub) {
+		set_bit(portnum, hub->wakeup_bits);
+		kick_khubd(hub);
+	}
+}
+EXPORT_SYMBOL_GPL(usb_wakeup_notification);
 
 /* completion function, fires on port status changes and various faults */
 static void hub_irq(struct urb *urb)
@@ -807,12 +832,6 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 			clear_port_feature(hub->hdev, port1,
 					USB_PORT_FEAT_C_ENABLE);
 		}
-		if (portchange & USB_PORT_STAT_C_LINK_STATE) {
-			need_debounce_delay = true;
-			clear_port_feature(hub->hdev, port1,
-					USB_PORT_FEAT_C_PORT_LINK_STATE);
-		}
-
 		if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
 				hub_is_superspeed(hub->hdev)) {
 			need_debounce_delay = true;
@@ -834,12 +853,19 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 				set_bit(port1, hub->change_bits);
 
 		} else if (portstatus & USB_PORT_STAT_ENABLE) {
+			bool port_resumed = (portstatus &
+					USB_PORT_STAT_LINK_STATE) ==
+				USB_SS_PORT_LS_U0;
 			/* The power session apparently survived the resume.
 			 * If there was an overcurrent or suspend change
 			 * (i.e., remote wakeup request), have khubd
-			 * take care of it.
+			 * take care of it.  Look at the port link state
+			 * for USB 3.0 hubs, since they don't have a suspend
+			 * change bit, and they don't set the port link change
+			 * bit on device-initiated resume.
 			 */
-			if (portchange)
+			if (portchange || (hub_is_superspeed(hub->hdev) &&
+						port_resumed))
 				set_bit(port1, hub->change_bits);
 
 		} else if (udev->persist_enabled) {
@@ -1289,14 +1315,8 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 	desc = intf->cur_altsetting;
 	hdev = interface_to_usbdev(intf);
 
-	/* Hubs have proper suspend/resume support.  USB 3.0 device suspend is
-	 * different from USB 2.0/1.1 device suspend, and unfortunately we
-	 * don't support it yet.  So leave autosuspend disabled for USB 3.0
-	 * external hubs for now.  Enable autosuspend for USB 3.0 roothubs,
-	 * since that isn't a "real" hub.
-	 */
-	if (!hub_is_superspeed(hdev) || !hdev->parent)
-		usb_enable_autosuspend(hdev);
+	/* Hubs have proper suspend/resume support. */
+	usb_enable_autosuspend(hdev);
 
 	if (hdev->level == MAX_TOPO_LEVEL) {
 		dev_err(&intf->dev,
@@ -2421,11 +2441,27 @@ int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
 	 * we don't explicitly enable it here.
 	 */
 	if (udev->do_remote_wakeup) {
-		status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
-				USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
-				USB_DEVICE_REMOTE_WAKEUP, 0,
-				NULL, 0,
-				USB_CTRL_SET_TIMEOUT);
+		if (!hub_is_superspeed(hub->hdev)) {
+			status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+					USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
+					USB_DEVICE_REMOTE_WAKEUP, 0,
+					NULL, 0,
+					USB_CTRL_SET_TIMEOUT);
+		} else {
+			/* Assume there's only one function on the USB 3.0
+			 * device and enable remote wake for the first
+			 * interface. FIXME if the interface association
+			 * descriptor shows there's more than one function.
+			 */
+			status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+					USB_REQ_SET_FEATURE,
+					USB_RECIP_INTERFACE,
+					USB_INTRF_FUNC_SUSPEND,
+					USB_INTRF_FUNC_SUSPEND_RW |
+					USB_INTRF_FUNC_SUSPEND_LP,
+					NULL, 0,
+					USB_CTRL_SET_TIMEOUT);
+		}
 		if (status) {
 			dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
 					status);
@@ -2715,6 +2751,7 @@ static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
 	struct usb_hub		*hub = usb_get_intfdata (intf);
 	struct usb_device	*hdev = hub->hdev;
 	unsigned		port1;
+	int			status;
 
 	/* Warn if children aren't already suspended */
 	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
@@ -2727,6 +2764,17 @@ static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
 				return -EBUSY;
 		}
 	}
+	if (hub_is_superspeed(hdev) && hdev->do_remote_wakeup) {
+		/* Enable hub to send remote wakeup for all ports. */
+		for (port1 = 1; port1 <= hdev->maxchild; port1++) {
+			status = set_port_feature(hdev,
+					port1 |
+					USB_PORT_FEAT_REMOTE_WAKE_CONNECT |
+					USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT |
+					USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT,
+					USB_PORT_FEAT_REMOTE_WAKE_MASK);
+		}
+	}
 
 	dev_dbg(&intf->dev, "%s\n", __func__);
 
@@ -3460,6 +3508,46 @@ done:
 		hcd->driver->relinquish_port(hcd, port1);
 }
 
+/* Returns 1 if there was a remote wakeup and a connect status change. */
+static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
+		u16 portstatus, u16 portchange)
+{
+	struct usb_device *hdev;
+	struct usb_device *udev;
+	int connect_change = 0;
+	int ret;
+
+	hdev = hub->hdev;
+	udev = hdev->children[port-1];
+	if (!hub_is_superspeed(hdev)) {
+		if (!(portchange & USB_PORT_STAT_C_SUSPEND))
+			return 0;
+		clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND);
+	} else {
+		if (!udev || udev->state != USB_STATE_SUSPENDED ||
+				 (portstatus & USB_PORT_STAT_LINK_STATE) !=
+				 USB_SS_PORT_LS_U0)
+			return 0;
+	}
+
+	if (udev) {
+		/* TRSMRCY = 10 msec */
+		msleep(10);
+
+		usb_lock_device(udev);
+		ret = usb_remote_wakeup(udev);
+		usb_unlock_device(udev);
+		if (ret < 0)
+			connect_change = 1;
+	} else {
+		ret = -ENODEV;
+		hub_port_disable(hub, port, 1);
+	}
+	dev_dbg(hub->intfdev, "resume on port %d, status %d\n",
+			port, ret);
+	return connect_change;
+}
+
 static void hub_events(void)
 {
 	struct list_head *tmp;
@@ -3472,7 +3560,7 @@ static void hub_events(void)
 	u16 portstatus;
 	u16 portchange;
 	int i, ret;
-	int connect_change;
+	int connect_change, wakeup_change;
 
 	/*
 	 *  We restart the list every time to avoid a deadlock with
@@ -3551,8 +3639,9 @@ static void hub_events(void)
 			if (test_bit(i, hub->busy_bits))
 				continue;
 			connect_change = test_bit(i, hub->change_bits);
+			wakeup_change = test_and_clear_bit(i, hub->wakeup_bits);
 			if (!test_and_clear_bit(i, hub->event_bits) &&
-					!connect_change)
+					!connect_change && !wakeup_change)
 				continue;
 
 			ret = hub_port_status(hub, i,
@@ -3593,31 +3682,10 @@ static void hub_events(void)
 				}
 			}
 
-			if (portchange & USB_PORT_STAT_C_SUSPEND) {
-				struct usb_device *udev;
+			if (hub_handle_remote_wakeup(hub, i,
+						portstatus, portchange))
+				connect_change = 1;
 
-				clear_port_feature(hdev, i,
-					USB_PORT_FEAT_C_SUSPEND);
-				udev = hdev->children[i-1];
-				if (udev) {
-					/* TRSMRCY = 10 msec */
-					msleep(10);
-
-					usb_lock_device(udev);
-					ret = usb_remote_wakeup(hdev->
-							children[i-1]);
-					usb_unlock_device(udev);
-					if (ret < 0)
-						connect_change = 1;
-				} else {
-					ret = -ENODEV;
-					hub_port_disable(hub, i, 1);
-				}
-				dev_dbg (hub_dev,
-					"resume on port %d, status %d\n",
-					i, ret);
-			}
-			
 			if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
 				u16 status = 0;
 				u16 unused;