usb: add helper to extract bits 12:11 of wMaxPacketSize

[pandora-kernel.git] / include / linux / usb / ch9.h

diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
index 046b1f4..68a3b10 100644 (file)
--- a/include/linux/usb/ch9.h
+++ b/include/linux/usb/ch9.h
@@ -390,6 +390,11 @@ struct usb_endpoint_descriptor {
 #define USB_ENDPOINT_XFER_INT          3
 #define USB_ENDPOINT_MAX_ADJUSTABLE    0x80
 
+#define USB_EP_MAXP_MULT_SHIFT 11
+#define USB_EP_MAXP_MULT_MASK  (3 << USB_EP_MAXP_MULT_SHIFT)
+#define USB_EP_MAXP_MULT(m) \
+       (((m) & USB_EP_MAXP_MULT_MASK) >> USB_EP_MAXP_MULT_SHIFT)
+
 #define USB_ENDPOINT_SYNCTYPE          0x0c
 #define USB_ENDPOINT_SYNC_NONE         (0 << 2)
 #define USB_ENDPOINT_SYNC_ASYNC                (1 << 2)
@@ -592,6 +597,20 @@ static inline int usb_endpoint_maxp(const struct usb_endpoint_descriptor *epd)
        return __le16_to_cpu(epd->wMaxPacketSize);
 }
 
+/**
+ * usb_endpoint_maxp_mult - get endpoint's transactional opportunities
+ * @epd: endpoint to be checked
+ *
+ * Return @epd's wMaxPacketSize[12:11] + 1
+ */
+static inline int
+usb_endpoint_maxp_mult(const struct usb_endpoint_descriptor *epd)
+{
+       int maxp = __le16_to_cpu(epd->wMaxPacketSize);
+
+       return USB_EP_MAXP_MULT(maxp) + 1;
+}
+
 /*-------------------------------------------------------------------------*/
 
 /* USB_DT_SS_ENDPOINT_COMP: SuperSpeed Endpoint Companion descriptor */