Commit fea34091 authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
Browse files

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: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent bdd016ba

drivers/usb/core/hcd.c

+2 −2
Original line number Diff line number Diff line
@@ -928,7 +928,7 @@ static void urb_unlink(struct usb_hcd *hcd, struct urb *urb) 
			dma_unmap_single (hcd->self.controller,

					urb->transfer_dma,

					urb->transfer_buffer_length,

					usb_pipein (urb->pipe)

					usb_urb_dir_in(urb)

					    ? DMA_FROM_DEVICE

					    : DMA_TO_DEVICE);

	}
@@ -1014,7 +1014,7 @@ int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags) 
					hcd->self.controller,

					urb->transfer_buffer,

					urb->transfer_buffer_length,

					usb_pipein (urb->pipe)

					usb_urb_dir_in(urb)

					    ? DMA_FROM_DEVICE

					    : DMA_TO_DEVICE);

	}

drivers/usb/core/urb.c

+16 −2
Original line number Diff line number Diff line
@@ -309,7 +309,21 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags) 
	 * and don't need to duplicate tests

	 */

	xfertype = usb_endpoint_type(&ep->desc);

	is_out = usb_pipeout(urb->pipe);

	if (xfertype == USB_ENDPOINT_XFER_CONTROL) {

		struct usb_ctrlrequest *setup =

				(struct usb_ctrlrequest *) urb->setup_packet;



		if (!setup)

			return -ENOEXEC;

		is_out = !(setup->bRequestType & USB_DIR_IN) ||

				!setup->wLength;

	} else {

		is_out = usb_endpoint_dir_out(&ep->desc);

	}



	/* Cache the direction for later use */

	urb->transfer_flags = (urb->transfer_flags & ~URB_DIR_MASK) |

			(is_out ? URB_DIR_OUT : URB_DIR_IN);



	if (xfertype != USB_ENDPOINT_XFER_CONTROL &&

			dev->state < USB_STATE_CONFIGURED)
@@ -363,7 +377,7 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags) 


	/* enforce simple/standard policy */

	allowed = (URB_NO_TRANSFER_DMA_MAP | URB_NO_SETUP_DMA_MAP |

			URB_NO_INTERRUPT);

			URB_NO_INTERRUPT | URB_DIR_MASK);

	switch (xfertype) {

	case USB_ENDPOINT_XFER_BULK:

		if (is_out)

include/linux/usb.h

+30 −0
Original line number Diff line number Diff line
@@ -1021,6 +1021,8 @@ extern int usb_disabled(void); 


/*

 * 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 @@ extern int usb_disabled(void); 
					 * 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 void usb_unanchor_urb(struct urb *urb); 
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,

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