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

illumos DDI specific (illumos 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(7) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
Architecture	PCI-based systems
Interface stability	Committed