1 files changed, 11 insertions, 3 deletions

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.)
          */
 };