--- /dev/null
+/* $NetBSD: i2c_io.h,v 1.3 2012/04/22 14:10:36 pgoyette Exp $ */
+
+/*
+ * Copyright (c) 2003 Wasabi Systems, Inc.
+ * All rights reserved.
+ *
+ * Written by Jason R. Thorpe for Wasabi Systems, Inc.
+ *
+ * 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. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed for the NetBSD Project by
+ * Wasabi Systems, Inc.
+ * 4. The name of Wasabi Systems, Inc. may not be used to endorse
+ * or promote products derived from this software without specific prior
+ * written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC
+ * 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.
+ */
+
+#ifndef _DEV_I2C_I2C_IO_H_
+#define _DEV_I2C_I2C_IO_H_
+
+#include <sys/ioccom.h>
+
+/* I2C bus address. */
+typedef uint16_t i2c_addr_t;
+
+/* High-level I2C operations. */
+#define I2C_OPMASK_STOP 1
+#define I2C_OPMASK_WRITE 2
+#define I2C_OPMASK_BLKMODE 4
+
+#define I2C_OP_STOP_P(x) (((int)(x) & I2C_OPMASK_STOP) != 0)
+#define I2C_OP_WRITE_P(x) (((int)(x) & I2C_OPMASK_WRITE) != 0)
+#define I2C_OP_READ_P(x) (!I2C_OP_WRITE_P(x))
+#define I2C_OP_BLKMODE_P(x) (((int)(x) & I2C_OPMASK_BLKMODE) != 0)
+
+typedef enum {
+ I2C_OP_READ = 0,
+ I2C_OP_READ_WITH_STOP = I2C_OPMASK_STOP,
+ I2C_OP_WRITE = I2C_OPMASK_WRITE,
+ I2C_OP_WRITE_WITH_STOP = I2C_OPMASK_WRITE | I2C_OPMASK_STOP,
+ I2C_OP_READ_BLOCK = I2C_OPMASK_BLKMODE | I2C_OPMASK_STOP,
+ I2C_OP_WRITE_BLOCK = I2C_OPMASK_BLKMODE | I2C_OPMASK_WRITE |
+ I2C_OPMASK_STOP,
+} i2c_op_t;
+
+/*
+ * This structure describes a single I2C control script fragment.
+ *
+ * Note that use of this scripted API allows for support of automated
+ * SMBus controllers. The following table maps SMBus operations to
+ * script fragment configuration:
+ *
+ * SMBus "write byte": I2C_OP_WRITE_WITH_STOP
+ * cmdlen = 1
+ *
+ * SMBus "read byte": I2C_OP_READ_WITH_STOP
+ * cmdlen = 1
+ *
+ * SMBus "receive byte": I2C_OP_READ_WITH_STOP
+ * cmdlen = 0
+ *
+ * Note that while each of these 3 SMBus operations implies a STOP
+ * (which an automated controller will likely perform automatically),
+ * non-SMBus clients may continue to function even if they issue
+ * I2C_OP_WRITE and I2C_OP_READ.
+ */
+
+/*
+ * I2C_IOCTL_EXEC:
+ *
+ * User ioctl to execute an i2c operation.
+ */
+typedef struct i2c_ioctl_exec {
+ i2c_op_t iie_op; /* operation to perform */
+ i2c_addr_t iie_addr; /* address of device */
+ const void *iie_cmd; /* pointer to command */
+ size_t iie_cmdlen; /* length of command */
+ void *iie_buf; /* pointer to data buffer */
+ size_t iie_buflen; /* length of data buffer */
+} i2c_ioctl_exec_t;
+#define I2C_EXEC_MAX_CMDLEN 32
+#define I2C_EXEC_MAX_BUFLEN 32
+
+#define I2C_IOCTL_EXEC _IOW('I', 0, i2c_ioctl_exec_t)
+
+#endif /* _DEV_I2C_I2C_IO_H_ */