diff --git a/drivers/usb/core/hcd.h b/drivers/usb/core/hcd.h
index 2d1c3d5e47b8..2c086b8460b1 100644
--- a/drivers/usb/core/hcd.h
+++ b/drivers/usb/core/hcd.h
@@ -28,7 +28,7 @@
 /*
  * USB Packet IDs (PIDs)
  */
-#define USB_PID_UNDEF_0			0xf0
+#define USB_PID_EXT			0xf0	/* USB 2.0 LPM ECN */
 #define USB_PID_OUT			0xe1
 #define USB_PID_ACK			0xd2
 #define USB_PID_DATA0			0xc3
diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index 1551aed65e05..d672cd81a3e4 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h
@@ -41,9 +41,10 @@
  */
 #define USB_PORT_FEAT_CONNECTION	0
 #define USB_PORT_FEAT_ENABLE		1
-#define USB_PORT_FEAT_SUSPEND		2
+#define USB_PORT_FEAT_SUSPEND		2	/* L2 suspend */
 #define USB_PORT_FEAT_OVER_CURRENT	3
 #define USB_PORT_FEAT_RESET		4
+#define USB_PORT_FEAT_L1		5	/* L1 suspend */
 #define USB_PORT_FEAT_POWER		8
 #define USB_PORT_FEAT_LOWSPEED		9
 #define USB_PORT_FEAT_HIGHSPEED		10
@@ -54,6 +55,7 @@
 #define USB_PORT_FEAT_C_RESET		20
 #define USB_PORT_FEAT_TEST              21
 #define USB_PORT_FEAT_INDICATOR         22
+#define USB_PORT_FEAT_C_PORT_L1         23
 
 /*
  * Hub Status and Hub Change results
@@ -73,7 +75,8 @@ struct usb_port_status {
 #define USB_PORT_STAT_SUSPEND		0x0004
 #define USB_PORT_STAT_OVERCURRENT	0x0008
 #define USB_PORT_STAT_RESET		0x0010
-/* bits 5 to 7 are reserved */
+#define USB_PORT_STAT_L1		0x0020
+/* bits 6 to 7 are reserved */
 #define USB_PORT_STAT_POWER		0x0100
 #define USB_PORT_STAT_LOW_SPEED		0x0200
 #define USB_PORT_STAT_HIGH_SPEED        0x0400
@@ -91,6 +94,7 @@ struct usb_port_status {
 #define USB_PORT_STAT_C_SUSPEND		0x0004
 #define USB_PORT_STAT_C_OVERCURRENT	0x0008
 #define USB_PORT_STAT_C_RESET		0x0010
+#define USB_PORT_STAT_C_L1		0x0020
 
 /*
  * wHubCharacteristics (masks)
diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
index 7e1da17ca7ce..61fcbc2b97da 100644
--- a/include/linux/usb/ch9.h
+++ b/include/linux/usb/ch9.h
@@ -66,8 +66,8 @@
 #define USB_RECIP_ENDPOINT		0x02
 #define USB_RECIP_OTHER			0x03
 /* From Wireless USB 1.0 */
-#define USB_RECIP_PORT 			0x04
-#define USB_RECIP_RPIPE 		0x05
+#define USB_RECIP_PORT			0x04
+#define USB_RECIP_RPIPE		0x05
 
 /*
  * Standard requests, for the bRequest field of a SETUP packet.
@@ -102,10 +102,16 @@
 #define USB_REQ_LOOPBACK_DATA_READ	0x16
 #define USB_REQ_SET_INTERFACE_DS	0x17
 
+/* The Link Power Mangement (LPM) ECN defines USB_REQ_TEST_AND_SET command,
+ * used by hubs to put ports into a new L1 suspend state, except that it
+ * forgot to define its number ...
+ */
+
 /*
  * USB feature flags are written using USB_REQ_{CLEAR,SET}_FEATURE, and
  * are read as a bit array returned by USB_REQ_GET_STATUS.  (So there
- * are at most sixteen features of each type.)
+ * are at most sixteen features of each type.)  Hubs may also support a
+ * new USB_REQ_TEST_AND_SET_FEATURE to put ports into L1 suspend.
  */
 #define USB_DEVICE_SELF_POWERED		0	/* (read only) */
 #define USB_DEVICE_REMOTE_WAKEUP	1	/* dev may initiate wakeup */
@@ -575,6 +581,8 @@ enum usb_device_state {
 	/* NOTE:  there are actually four different SUSPENDED
 	 * states, returning to POWERED, DEFAULT, ADDRESS, or
 	 * CONFIGURED respectively when SOF tokens flow again.
+	 * At this level there's no difference between L1 and L2
+	 * suspend states.  (L2 being original USB 1.1 suspend.)
 	 */
 };