3.18-stable review patch. If anyone has any objections, please let me know.
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From: Ravi Chandra Sadineni ravisadineni@chromium.org
commit 83a62c51ba7b3c0bf45150c4eac7aefc6c785e94 upstream.
On chromebooks we depend on wakeup count to identify the wakeup source. But currently USB devices do not increment the wakeup count when they trigger the remote wake. This patch addresses the same.
Resume condition is reported differently on USB 2.0 and USB 3.0 devices.
On USB 2.0 devices, a wake capable device, if wake enabled, drives resume signal to indicate a remote wake (USB 2.0 spec section 7.1.7.7). The upstream facing port then sets C_PORT_SUSPEND bit and reports a port change event (USB 2.0 spec section 11.24.2.7.2.3). Thus if a port has resumed before driving the resume signal from the host and C_PORT_SUSPEND is set, then the device attached to the given port might be the reason for the last system wakeup. Increment the wakeup count for the same.
On USB 3.0 devices, a function may signal that it wants to exit from device suspend by sending a Function Wake Device Notification to the host (USB3.0 spec section 8.5.6.4) Thus on receiving the Function Wake, increment the wakeup count.
Signed-off-by: Ravi Chandra Sadineni ravisadineni@chromium.org Acked-by: Alan Stern stern@rowland.harvard.edu Cc: stable stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/usb/core/hcd.c | 1 + drivers/usb/core/hub.c | 10 +++++++++- 2 files changed, 10 insertions(+), 1 deletion(-)
--- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -2289,6 +2289,7 @@ void usb_hcd_resume_root_hub (struct usb
spin_lock_irqsave (&hcd_root_hub_lock, flags); if (hcd->rh_registered) { + pm_wakeup_event(&hcd->self.root_hub->dev, 0); set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags); queue_work(pm_wq, &hcd->wakeup_work); } --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -633,12 +633,17 @@ void usb_wakeup_notification(struct usb_ unsigned int portnum) { struct usb_hub *hub; + struct usb_port *port_dev;
if (!hdev) return;
hub = usb_hub_to_struct_hub(hdev); if (hub) { + port_dev = hub->ports[portnum - 1]; + if (port_dev && port_dev->child) + pm_wakeup_event(&port_dev->child->dev, 0); + set_bit(portnum, hub->wakeup_bits); kick_hub_wq(hub); } @@ -3363,8 +3368,11 @@ int usb_port_resume(struct usb_device *u
/* Skip the initial Clear-Suspend step for a remote wakeup */ status = hub_port_status(hub, port1, &portstatus, &portchange); - if (status == 0 && !port_is_suspended(hub, portstatus)) + if (status == 0 && !port_is_suspended(hub, portstatus)) { + if (portchange & USB_PORT_STAT_C_SUSPEND) + pm_wakeup_event(&udev->dev, 0); goto SuspendCleared; + }
/* see 7.1.7.7; affects power usage, but not budgeting */ if (hub_is_superspeed(hub->hdev))