1 files changed, 23 insertions, 13 deletions

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 673ee4696262..64854d76f529 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -3241,8 +3241,7 @@ static int usb_req_set_sel(struct usb_device *udev, enum usb3_link_state state)
 			(state == USB3_LPM_U2 &&
 			 (u2_sel > USB3_LPM_MAX_U2_SEL_PEL ||
 			  u2_pel > USB3_LPM_MAX_U2_SEL_PEL))) {
-		dev_dbg(&udev->dev, "Device-initiated %s disabled due "
-				"to long SEL %llu ms or PEL %llu ms\n",
+		dev_dbg(&udev->dev, "Device-initiated %s disabled due to long SEL %llu us or PEL %llu us\n",
 				usb3_lpm_names[state], u1_sel, u1_pel);
 		return -EINVAL;
 	}
@@ -3320,16 +3319,6 @@ static int usb_set_device_initiated_lpm(struct usb_device *udev,
 
 	if (enable) {
 		/*
-		 * First, let the device know about the exit latencies
-		 * associated with the link state we're about to enable.
-		 */
-		ret = usb_req_set_sel(udev, state);
-		if (ret < 0) {
-			dev_warn(&udev->dev, "Set SEL for device-initiated "
-					"%s failed.\n", usb3_lpm_names[state]);
-			return -EBUSY;
-		}
-		/*
 		 * Now send the control transfer to enable device-initiated LPM
 		 * for either U1 or U2.
 		 */
@@ -3414,7 +3403,28 @@ static int usb_set_lpm_timeout(struct usb_device *udev,
 static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
 		enum usb3_link_state state)
 {
-	int timeout;
+	int timeout, ret;
+	__u8 u1_mel = udev->bos->ss_cap->bU1devExitLat;
+	__le16 u2_mel = udev->bos->ss_cap->bU2DevExitLat;
+
+	/* If the device says it doesn't have *any* exit latency to come out of
+	 * U1 or U2, it's probably lying.  Assume it doesn't implement that link
+	 * state.
+	 */
+	if ((state == USB3_LPM_U1 && u1_mel == 0) ||
+			(state == USB3_LPM_U2 && u2_mel == 0))
+		return;
+
+	/*
+	 * First, let the device know about the exit latencies
+	 * associated with the link state we're about to enable.
+	 */
+	ret = usb_req_set_sel(udev, state);
+	if (ret < 0) {
+		dev_warn(&udev->dev, "Set SEL for device-initiated %s failed.\n",
+				usb3_lpm_names[state]);
+		return;
+	}
 
 	/* We allow the host controller to set the U1/U2 timeout internally
 	 * first, so that it can change its schedule to account for the