usb_pipe_get_state(9F)					   Kernel Functions for Drivers 				    usb_pipe_get_state(9F)

NAME

       usb_pipe_get_state - Return USB pipe state

SYNOPSIS

       #include <sys/usb/usba.h>

       int usb_pipe_get_state(usb_pipe_handle_t pipe_handle,
	    usb_pipe_state_t *pipe_state, usb_flags_t usb_flags);

INTERFACE LEVEL

       Solaris DDI specific (Solaris DDI)

PARAMETERS

       pipe_handle    Handle of the pipe to retrieve the state.

       pipe_state     Pointer to where pipe state is returned.

       usb_flags      No flags are recognized. Reserved for future expansion.

DESCRIPTION

       The usb_pipe_get_state() function retrieves the state of the pipe referred to by pipe_handle into the location pointed to by pipe_state.

       Possible pipe states are:

       USB_PIPE_STATE_CLOSED	 Pipe is closed.

       USB_PIPE_STATE_ACTIVE	 Pipe is active and can send/receive data. Polling is active for isochronous and interrupt pipes.

       USB_PIPE_STATE_IDLE	 Polling is stopped for isochronous and interrupt-IN pipes.

       USB_PIPE_STATE_ERROR	 An  error  occurred.  Client  must call usb_pipe_reset(). Note that this status is not seen by a client driver if
				 USB_ATTRS_AUTOCLEARING is set in the request attributes.

       USB_PIPE_STATE_CLOSING	 Pipe is being closed. Requests are being drained from the pipe and other cleanup is in progress.

RETURN VALUES

       USB_SUCCESS	   Pipe state returned in second argument.

       USB_INVALID_ARGS    Pipe_state argument is NULL.

       USB_INVALID_PIPE    Pipe_handle argument is NULL.

CONTEXT

       May be called from user, kernel or interrupt context.

EXAMPLES

	     usb_pipe_handle_t pipe;
	     usb_pipe_state_t state;

	     /* Recover if the pipe is in an error state. */
	     if ((usb_pipe_get_state(pipe, &state, 0) == USB_SUCCESS) &&
		 (state == USB_PIPE_STATE_ERROR)) {
		     cmn_err (CE_WARN, "%s%d: USB Pipe error.",
			 ddi_driver_name(dip), ddi_get_instance(dip));
		     do_recovery();
	     }

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Architecture		     |PCI-based systems 	   |
       +-----------------------------+-----------------------------+
       |Interface stability	     |Committed 		   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWusb			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       attributes(5), usb_clr_feature(9F), usb_get_cfg(9F).  usb_get_status(9F),  usb_pipe_close(9F),  usb_pipe_ctrl_xfer(9F),	usb_pipe_open(9F).
       usb_pipe_reset(9F)

SunOS 5.11							    5 Jan 2004						    usb_pipe_get_state(9F)