USB: add direction bit to urb->transfer_flags
This patch (as945) adds a bit to urb->transfer_flags for recording the
direction of the URB. The bit is set/cleared automatically in
usb_submit_urb() so drivers don't have to worry about it (although as
a result, it isn't valid until the URB has been submitted). Inline
routines are added for easily checking an URB's direction. They
replace calls to usb_pipein in the DMA-mapping parts of hcd.c.
For non-control endpoints, the direction is determined directly from
the endpoint descriptor. However control endpoints are
bi-directional; for them the direction is determined from the
bRequestType byte and the wLength value in the setup packet.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/include/linux/usb.h b/include/linux/usb.h
index 818a1b4..9d08f5a 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -1021,6 +1021,8 @@
/*
* urb->transfer_flags:
+ *
+ * Note: URB_DIR_IN/OUT is automatically set in usb_submit_urb().
*/
#define URB_SHORT_NOT_OK 0x0001 /* report short reads as errors */
#define URB_ISO_ASAP 0x0002 /* iso-only, urb->start_frame
@@ -1033,6 +1035,10 @@
* needed */
#define URB_FREE_BUFFER 0x0100 /* Free transfer buffer with the URB */
+#define URB_DIR_IN 0x0200 /* Transfer from device to host */
+#define URB_DIR_OUT 0
+#define URB_DIR_MASK URB_DIR_IN
+
struct usb_iso_packet_descriptor {
unsigned int offset;
unsigned int length; /* expected length */
@@ -1380,6 +1386,30 @@
extern int usb_wait_anchor_empty_timeout(struct usb_anchor *anchor,
unsigned int timeout);
+/**
+ * usb_urb_dir_in - check if an URB describes an IN transfer
+ * @urb: URB to be checked
+ *
+ * Returns 1 if @urb describes an IN transfer (device-to-host),
+ * otherwise 0.
+ */
+static inline int usb_urb_dir_in(struct urb *urb)
+{
+ return (urb->transfer_flags & URB_DIR_MASK) != URB_DIR_OUT;
+}
+
+/**
+ * usb_urb_dir_out - check if an URB describes an OUT transfer
+ * @urb: URB to be checked
+ *
+ * Returns 1 if @urb describes an OUT transfer (host-to-device),
+ * otherwise 0.
+ */
+static inline int usb_urb_dir_out(struct urb *urb)
+{
+ return (urb->transfer_flags & URB_DIR_MASK) == URB_DIR_OUT;
+}
+
void *usb_buffer_alloc (struct usb_device *dev, size_t size,
gfp_t mem_flags, dma_addr_t *dma);
void usb_buffer_free (struct usb_device *dev, size_t size,