[ 19/26] usb: Using correct way to clear usb3.0 devices remote wakeup feature.

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

3.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Lan Tianyu <tianyu.lan@intel.com>

commit 54a3ac0c9e5b7213daa358ce74d154352657353a upstream.

Usb3.0 device defines function remote wakeup which is only for interface
recipient rather than device recipient. This is different with usb2.0 device's
remote wakeup feature which is defined for device recipient. According usb3.0
spec 9.4.5, the function remote wakeup can be modified by the SetFeature()
requests using the FUNCTION_SUSPEND feature selector. This patch is to use
correct way to disable usb3.0 device's function remote wakeup after suspend
error and resuming.

This should be backported to kernels as old as 3.4, that contain the
commit 623bef9e03a60adc623b09673297ca7a1cdfb367 "USB/xhci: Enable remote
wakeup for USB3 devices."

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/core/hub.c  |   70 +++++++++++++++++++++++++++++++++++-------------
 include/linux/usb/ch9.h |    6 ++++
 2 files changed, 58 insertions(+), 18 deletions(-)

--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2463,6 +2463,23 @@ static int check_port_resume_type(struct
 }
 
 #ifdef	CONFIG_USB_SUSPEND
+/*
+ * usb_disable_function_remotewakeup - disable usb3.0
+ * device's function remote wakeup
+ * @udev: target device
+ *
+ * Assume there's only one function on the USB 3.0
+ * device and disable remote wake for the first
+ * interface. FIXME if the interface association
+ * descriptor shows there's more than one function.
+ */
+static int usb_disable_function_remotewakeup(struct usb_device *udev)
+{
+	return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+				USB_REQ_CLEAR_FEATURE, USB_RECIP_INTERFACE,
+				USB_INTRF_FUNC_SUSPEND,	0, NULL, 0,
+				USB_CTRL_SET_TIMEOUT);
+}
 
 /*
  * usb_port_suspend - suspend a usb device's upstream port
@@ -2569,12 +2586,19 @@ int usb_port_suspend(struct usb_device *
 		dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
 				port1, status);
 		/* paranoia:  "should not happen" */
-		if (udev->do_remote_wakeup)
-			(void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
-				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
-				USB_DEVICE_REMOTE_WAKEUP, 0,
-				NULL, 0,
-				USB_CTRL_SET_TIMEOUT);
+		if (udev->do_remote_wakeup) {
+			if (!hub_is_superspeed(hub->hdev)) {
+				(void) usb_control_msg(udev,
+						usb_sndctrlpipe(udev, 0),
+						USB_REQ_CLEAR_FEATURE,
+						USB_RECIP_DEVICE,
+						USB_DEVICE_REMOTE_WAKEUP, 0,
+						NULL, 0,
+						USB_CTRL_SET_TIMEOUT);
+			} else
+				(void) usb_disable_function_remotewakeup(udev);
+
+		}
 
 		/* Try to enable USB2 hardware LPM again */
 		if (udev->usb2_hw_lpm_capable == 1)
@@ -2661,20 +2685,30 @@ static int finish_port_resume(struct usb
 	 * udev->reset_resume
 	 */
 	} else if (udev->actconfig && !udev->reset_resume) {
-		le16_to_cpus(&devstatus);
-		if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
-			status = usb_control_msg(udev,
-					usb_sndctrlpipe(udev, 0),
-					USB_REQ_CLEAR_FEATURE,
+		if (!hub_is_superspeed(udev->parent)) {
+			le16_to_cpus(&devstatus);
+			if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
+				status = usb_control_msg(udev,
+						usb_sndctrlpipe(udev, 0),
+						USB_REQ_CLEAR_FEATURE,
 						USB_RECIP_DEVICE,
-					USB_DEVICE_REMOTE_WAKEUP, 0,
-					NULL, 0,
-					USB_CTRL_SET_TIMEOUT);
-			if (status)
-				dev_dbg(&udev->dev,
-					"disable remote wakeup, status %d\n",
-					status);
+						USB_DEVICE_REMOTE_WAKEUP, 0,
+						NULL, 0,
+						USB_CTRL_SET_TIMEOUT);
+		} else {
+			status = usb_get_status(udev, USB_RECIP_INTERFACE, 0,
+					&devstatus);
+			le16_to_cpus(&devstatus);
+			if (!status && devstatus & (USB_INTRF_STAT_FUNC_RW_CAP
+					| USB_INTRF_STAT_FUNC_RW))
+				status =
+					usb_disable_function_remotewakeup(udev);
 		}
+
+		if (status)
+			dev_dbg(&udev->dev,
+				"disable remote wakeup, status %d\n",
+				status);
 		status = 0;
 	}
 	return status;
--- a/include/linux/usb/ch9.h
+++ b/include/linux/usb/ch9.h
@@ -150,6 +150,12 @@
 #define USB_INTRF_FUNC_SUSPEND_LP	(1 << (8 + 0))
 #define USB_INTRF_FUNC_SUSPEND_RW	(1 << (8 + 1))
 
+/*
+ * Interface status, Figure 9-5 USB 3.0 spec
+ */
+#define USB_INTRF_STAT_FUNC_RW_CAP     1
+#define USB_INTRF_STAT_FUNC_RW         2
+
 #define USB_ENDPOINT_HALT		0	/* IN/OUT will STALL */
 
 /* Bit array elements as returned by the USB_REQ_GET_STATUS request. */