/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#ifndef _SYS_POLLED_IO_H
#define _SYS_POLLED_IO_H

#pragma ident   "%Z%%M% %I%     %E% SMI"

#ifdef  __cplusplus
extern "C" {
#endif

typedef struct polled_device {
        /*
         * This lock is only used to lock writing from
         * the fields on the structure.  The values in the
         * structure can be read under obp, so the lock
         * isn't valid then.
         */
        kmutex_t        polled_device_lock;

        /*
         * When we switch over the console, this is the old value
         * so that we can restore it later.
         */
        uint64_t        polled_old_handle;

        /*
         * Pointer to registerd polled I/O callbacks.
         */
        cons_polledio_t *polled_io;

} polled_device_t;

_NOTE(MUTEX_PROTECTS_DATA(polled_device_t::polled_device_lock,
        polled_device_t))

#define CIF_SUCCESS     ((uint_t)0)
#define CIF_FAILURE     ((uint_t)-1)

/*
 * The lower layers did not find any characters.
 */
#define CIF_NO_CHARACTERS       ((uint_t)-2)

/*
 * Every CIF has at least 3 arguments:  0 (name), 1 (in args), and 2 (out args).
 */
#define CIF_MIN_SIZE            3

#define CIF_NAME                0       /* name of function */
#define CIF_NUMBER_IN_ARGS      1       /* number of arguments passed in */
#define CIF_NUMBER_OUT_ARGS     2       /* number of arguments for return */

/*
 * These are the types of polled I/O that this module handles.
 */
typedef enum polled_io_console_type {
        POLLED_IO_CONSOLE_INPUT = 0,
        POLLED_IO_CONSOLE_OUTPUT = 1
} polled_io_console_type_t;

/*
 * Initialize the polled I/O kernel structures
 */
void    polled_io_init(void);

/*
 * De-initialize the polled I/O kernel structures
 */
void    polled_io_fini(void);

/*
 * Register a device to be used as a console for OBP.
 */
int     polled_io_register_callbacks(cons_polledio_t *, int);

/*
 * Unregister a device to be used as a console for OBP.
 */
int     polled_io_unregister_callbacks(cons_polledio_t *, int);

void    polled_io_cons_write(uchar_t *, size_t);

#ifdef  __cplusplus
}
#endif

#endif  /* _SYS_POLLED_IO_H */