USB: Add macros for interrupt endpoint types.

The USB 3.0 spec defines a new way of differentiating interrupt
endpoints.  The idea is that some interrupt endpoints are used for
notifications, i.e. they continually NAK the transfer until something
changes on the device.  Other interrupt endpoints are used as a way to
periodically transfer data.

The USB 3.0 endpoint descriptor uses bits 5:4 of bmAttributes for
interrupt endpoints, to define the endpoint as either a Notification
endpoint, or a Periodic endpoint.  Introduce macros to dig out that
information.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>

diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
index 43bce9da7a4dba46bcd470b1224ba770b297e9b0..d1d732c2838d3a48788c16fe87bd9552a8558ab8 100644 (file)
--- a/include/linux/usb/ch9.h
+++ b/include/linux/usb/ch9.h
@@ -392,6 +392,11 @@ struct usb_endpoint_descriptor {
 #define USB_ENDPOINT_XFER_INT          3
 #define USB_ENDPOINT_MAX_ADJUSTABLE    0x80
 
+/* The USB 3.0 spec redefines bits 5:4 of bmAttributes as interrupt ep type. */
+#define USB_ENDPOINT_INTRTYPE          0x30
+#define USB_ENDPOINT_INTR_PERIODIC     (0 << 4)
+#define USB_ENDPOINT_INTR_NOTIFICATION (1 << 4)
+
 #define USB_ENDPOINT_SYNCTYPE          0x0c
 #define USB_ENDPOINT_SYNC_NONE         (0 << 2)
 #define USB_ENDPOINT_SYNC_ASYNC                (1 << 2)
@@ -594,6 +599,12 @@ static inline int usb_endpoint_maxp(const struct usb_endpoint_descriptor *epd)
        return __le16_to_cpu(epd->wMaxPacketSize);
 }
 
+static inline int usb_endpoint_interrupt_type(
+               const struct usb_endpoint_descriptor *epd)
+{
+       return epd->bmAttributes & USB_ENDPOINT_INTRTYPE;
+}
+
 /*-------------------------------------------------------------------------*/
 
 /* USB_DT_SS_ENDPOINT_COMP: SuperSpeed Endpoint Companion descriptor */