From: Chris Chiu <chris.chiu@xxxxxxxxxxxxx>
On the Realtek hub of Dell Dock WD19, the port which has wakeup
enabled descendants will sometimes timeout when setting PORT_SUSPEND
feature. After checking the PORT_SUSPEND bit in wPortStatus, it is
already set. However, the hub will fail to activate because the
PORT_SUSPEND feature of that port is not cleared during resume. All
devices connecting via the port are lost after resume.
This commit force reset-resume the device connected to the timeout
but suspended port so that the hub will have chance to clear the
PORT_SUSPEND feature during resume.
Signed-off-by: Chris Chiu <chris.chiu@xxxxxxxxxxxxx>
---
drivers/usb/core/hub.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index b2bc4b7c4289..18603949a8de 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -3385,6 +3385,21 @@ int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
status = 0;
}
if (status) {
+ if (status == -ETIMEDOUT) {
+ u16 portstatus, portchange;
+
+ status = hub_port_status(hub, port1, &portstatus,
+ &portchange);
+
+ dev_dbg(&port_dev->dev,
+ "suspend timeout, status %04x\n", portstatus);
+
+ if (status == 0 && port_is_suspended(hub, portstatus)) {
+ udev->reset_resume = 1;
+ goto err_wakeup;
+ }
+ }
+
dev_dbg(&port_dev->dev, "can't suspend, status %d\n", status);
/* Try to enable USB3 LTM again */
--
2.20.1
