.\" $OpenBSD: openprom.4,v 1.5 2003/06/02 23:30:14 millert Exp $ .\" Copyright (c) 1992, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" This software was developed by the Computer Systems Engineering group .\" at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and .\" contributed to Berkeley. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" from: @(#)openprom.4 8.1 (Berkeley) 6/5/93 .\" .Dd June 5, 1993 .Dt OPENPROM 4 sparc .Os .Sh NAME .Nm openprom .Nd OPENPROM and EEPROM interface .Sh SYNOPSIS .Fd #include .Sh DESCRIPTION The file .Pa /dev/openprom is an interface to the SPARC OPENPROM, including the EEPROM area. This interface is highly stylized; ioctls are used for all operations. These ioctls refer to .Dq nodes , which are simply .Dq magic integer values describing data areas. Occasionally the number 0 may be used or returned instead, as described below. A special distinguished .Dq options node holds the EEPROM settings. .Pp The calls that take and/or return a node use a pointer to an .Li int variable for this purpose; others use a pointer to a .Li struct opiocdesc descriptor, which contains a node and two counted strings. The first string is comprised of the fields .Li op_namelen (an .Li int ) and .Li op_name (a .Li "char *" ) , giving the name of a field. The second string is comprised of the fields .Li op_buflen and .Li op_buf , used analogously. These two counted strings work in a .Dq value-result fashion. At entry to the ioctl, the counts are expected to reflect the buffer size; on return, the counts are updated to reflect the buffer contents. .Pp The following ioctls are supported: .Bl -tag -width OPIOCGETOPTNODE .It Dv OPIOCGETOPTNODE Takes nothing, and fills in the options node number. .It OPIOCGETNEXT Takes a node number and returns the number of the following node. The node following the last node is number 0; the node following number 0 is the first node. .It Dv OPIOCGETCHILD Takes a node number and returns the number of the first .Dq child of that node. This child may have siblings; these can be discovered by using .Dv OPIOCGETNEXT . .It Dv OPIOCGET Fills in the value of the named property for the given node. If no such property is associated with that node, the value length is set to -1. If the named property exists but has no value, the value length is set to 0. .It Dv OPIOCSET Writes the given value under the given name. The OPENPROM may refuse this operation; in this case .Dv EINVAL is returned. .It Dv OPIOCNEXTPROP Finds the property whose name follows the given name in OPENPROM internal order. The resulting name is returned in the value field. If the named property is the last, the .Dq next name is the empty string. As with .Dv OPIOCGETNEXT , the next name after the empty string is the first name. .El .Sh FILES .Li /dev/openprom .Sh ERRORS The following may result in rejection of an operation: .Bl -tag -width Er .It Bq Er EINVAL The given node number is not zero and does not correspond to any valid node, or is zero where zero is not allowed. .It Bq Er EBADF The requested operation requires permissions not specified at the call to .Fn open . .It Bq Er ENAMETOOLONG The given name or value field exceeds the maximum allowed length (8191 bytes). .El .Sh SEE ALSO .Xr ioctl 2 , .Xr eeprom 8 .Sh BUGS Due to limitations within the OPENPROM itself, these functions run at elevated priority and may adversely affect system performance.