Commit 782a7a63 authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

[PATCH] USB: add usb_interrupt_msg() function for api completeness. 



Really just a wrapper around usb_bulk_msg() but now it's documented
much better.

Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent caa2a122

drivers/usb/core/message.c

+31 −0
Original line number Diff line number Diff line
@@ -157,6 +157,37 @@ int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request, __u 
}





/**

 * usb_interrupt_msg - Builds an interrupt urb, sends it off and waits for completion

 * @usb_dev: pointer to the usb device to send the message to

 * @pipe: endpoint "pipe" to send the message to

 * @data: pointer to the data to send

 * @len: length in bytes of the data to send

 * @actual_length: pointer to a location to put the actual length transferred in bytes

 * @timeout: time in msecs to wait for the message to complete before

 *	timing out (if 0 the wait is forever)

 * Context: !in_interrupt ()

 *

 * This function sends a simple interrupt message to a specified endpoint and

 * waits for the message to complete, or timeout.

 *

 * If successful, it returns 0, otherwise a negative error number.  The number

 * of actual bytes transferred will be stored in the actual_length paramater.

 *

 * Don't use this function from within an interrupt context, like a bottom half

 * handler.  If you need an asynchronous message, or need to send a message

 * from within interrupt context, use usb_submit_urb() If a thread in your

 * driver uses this call, make sure your disconnect() method can wait for it to

 * complete.  Since you don't have a handle on the URB used, you can't cancel

 * the request.

 */

int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe,

		      void *data, int len, int *actual_length, int timeout)

{

	return usb_bulk_msg(usb_dev, pipe, data, len, actual_length, timeout);

}

EXPORT_SYMBOL_GPL(usb_interrupt_msg);



/**

 *	usb_bulk_msg - Builds a bulk urb, sends it off and waits for completion

 *	@usb_dev: pointer to the usb device to send the message to

include/linux/usb.h

+2 −0
Original line number Diff line number Diff line
@@ -1008,6 +1008,8 @@ void usb_buffer_unmap_sg (struct usb_device *dev, unsigned pipe, 
extern int usb_control_msg(struct usb_device *dev, unsigned int pipe,

	__u8 request, __u8 requesttype, __u16 value, __u16 index,

	void *data, __u16 size, int timeout);

extern int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe,

	void *data, int len, int *actual_length, int timeout);

extern int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe,

	void *data, int len, int *actual_length,

	int timeout);