USB: EHCI: EHCI 1.1 addendum: Basic LPM feature support

With this patch, the LPM capable EHCI host controller can put device
into L1 sleep state which is a mode that can enter/exit quickly, and
reduce power consumption.

Signed-off-by: Jacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: Alek Du <alek.du@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index d43d176..a307d55 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -361,6 +361,22 @@
 }
 #endif
 
+static int ehci_update_device(struct usb_hcd *hcd, struct usb_device *udev)
+{
+	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+	int rc = 0;
+
+	if (!udev->parent) /* udev is root hub itself, impossible */
+		rc = -1;
+	/* we only support lpm device connected to root hub yet */
+	if (ehci->has_lpm && !udev->parent->parent) {
+		rc = ehci_lpm_set_da(ehci, udev->devnum, udev->portnum);
+		if (!rc)
+			rc = ehci_lpm_check(ehci, udev->portnum);
+	}
+	return rc;
+}
+
 static const struct hc_driver ehci_pci_hc_driver = {
 	.description =		hcd_name,
 	.product_desc =		"EHCI Host Controller",
@@ -407,6 +423,11 @@
 	.relinquish_port =	ehci_relinquish_port,
 	.port_handed_over =	ehci_port_handed_over,
 
+	/*
+	 * call back when device connected and addressed
+	 */
+	.update_device =	ehci_update_device,
+
 	.clear_tt_buffer_complete	= ehci_clear_tt_buffer_complete,
 };