usb: core: lpm: fix usb3_hardware_lpm sysfs node

Commit 655fe4effe0f ("usbcore: add sysfs support to xHCI usb3
hardware LPM") introduced usb3_hardware_lpm sysfs node. This
doesn't show the correct status of USB3 U1 and U2 LPM status.

This patch fixes this by replacing usb3_hardware_lpm with two
nodes, usb3_hardware_lpm_u1 (for U1) and usb3_hardware_lpm_u2
(for U2), and recording the U1/U2 LPM status in right places.

This patch should be back-ported to kernels as old as 4.3,
that contains Commit 655fe4effe0f ("usbcore: add sysfs support
to xHCI usb3 hardware LPM").

Cc: stable@vger.kernel.org
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c
index d9ec2de6c..65b6e6b 100644
--- a/drivers/usb/core/sysfs.c
+++ b/drivers/usb/core/sysfs.c
@@ -531,7 +531,7 @@
 }
 static DEVICE_ATTR_RW(usb2_lpm_besl);
 
-static ssize_t usb3_hardware_lpm_show(struct device *dev,
+static ssize_t usb3_hardware_lpm_u1_show(struct device *dev,
 				      struct device_attribute *attr, char *buf)
 {
 	struct usb_device *udev = to_usb_device(dev);
@@ -539,7 +539,7 @@
 
 	usb_lock_device(udev);
 
-	if (udev->usb3_lpm_enabled)
+	if (udev->usb3_lpm_u1_enabled)
 		p = "enabled";
 	else
 		p = "disabled";
@@ -548,7 +548,26 @@
 
 	return sprintf(buf, "%s\n", p);
 }
-static DEVICE_ATTR_RO(usb3_hardware_lpm);
+static DEVICE_ATTR_RO(usb3_hardware_lpm_u1);
+
+static ssize_t usb3_hardware_lpm_u2_show(struct device *dev,
+				      struct device_attribute *attr, char *buf)
+{
+	struct usb_device *udev = to_usb_device(dev);
+	const char *p;
+
+	usb_lock_device(udev);
+
+	if (udev->usb3_lpm_u2_enabled)
+		p = "enabled";
+	else
+		p = "disabled";
+
+	usb_unlock_device(udev);
+
+	return sprintf(buf, "%s\n", p);
+}
+static DEVICE_ATTR_RO(usb3_hardware_lpm_u2);
 
 static struct attribute *usb2_hardware_lpm_attr[] = {
 	&dev_attr_usb2_hardware_lpm.attr,
@@ -562,7 +581,8 @@
 };
 
 static struct attribute *usb3_hardware_lpm_attr[] = {
-	&dev_attr_usb3_hardware_lpm.attr,
+	&dev_attr_usb3_hardware_lpm_u1.attr,
+	&dev_attr_usb3_hardware_lpm_u2.attr,
 	NULL,
 };
 static struct attribute_group usb3_hardware_lpm_attr_group = {
@@ -592,7 +612,8 @@
 		if (udev->usb2_hw_lpm_capable == 1)
 			rc = sysfs_merge_group(&dev->kobj,
 					&usb2_hardware_lpm_attr_group);
-		if (udev->lpm_capable == 1)
+		if (udev->speed == USB_SPEED_SUPER &&
+				udev->lpm_capable == 1)
 			rc = sysfs_merge_group(&dev->kobj,
 					&usb3_hardware_lpm_attr_group);
 	}