xref: /netbsd-src/sys/dev/i2c/i2cvar.h (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: i2cvar.h,v 1.1 2003/09/30 00:35:31 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 2003 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Steve C. Woodford and Jason R. Thorpe for Wasabi Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed for the NetBSD Project by
20  *      Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #ifndef _DEV_I2C_I2CVAR_H_
39 #define	_DEV_I2C_I2CVAR_H_
40 
41 #include <dev/i2c/i2c_io.h>
42 
43 /* Flags passed to i2c routines. */
44 #define	I2C_F_WRITE		0x00	/* new transfer is a write */
45 #define	I2C_F_READ		0x01	/* new transfer is a read */
46 #define	I2C_F_LAST		0x02	/* last byte of read */
47 #define	I2C_F_STOP		0x04	/* send stop after byte */
48 #define	I2C_F_POLL		0x08	/* poll, don't sleep */
49 
50 /*
51  * This structure provides the interface between the i2c framework
52  * and the underlying i2c controller.
53  *
54  * Note that this structure is designed specifically to allow us
55  * to either use the autoconfiguration framework or not.  This
56  * allows a driver for a board with a private i2c bus use generic
57  * i2c client drivers for chips that might be on that board.
58  */
59 typedef struct i2c_controller {
60 	void	*ic_cookie;		/* controller private */
61 
62 	/*
63 	 * These provide synchronization in the presence of
64 	 * multiple users of the i2c bus.  When a device
65 	 * driver wishes to perform transfers on the i2c
66 	 * bus, the driver should acquire the bus.  When
67 	 * the driver is finished, it should release the
68 	 * bus.
69 	 *
70 	 * This is provided by the back-end since a single
71 	 * controller may present e.g. i2c and smbus views
72 	 * of the same set of i2c wires.
73 	 */
74 	int	(*ic_acquire_bus)(void *, int);
75 	void	(*ic_release_bus)(void *, int);
76 
77 	/*
78 	 * The preferred API for clients of the i2c interface
79 	 * is the scripted API.  This handles i2c controllers
80 	 * that do not provide raw access to the i2c signals.
81 	 */
82 	int	(*ic_exec)(void *, i2c_op_t, i2c_addr_t, const void *, size_t,
83 		    void *, size_t, int);
84 
85 	int	(*ic_send_start)(void *, int);
86 	int	(*ic_send_stop)(void *, int);
87 	int	(*ic_initiate_xfer)(void *, i2c_addr_t, int);
88 	int	(*ic_read_byte)(void *, uint8_t *, int);
89 	int	(*ic_write_byte)(void *, uint8_t, int);
90 } *i2c_tag_t;
91 
92 /* Used to attach the i2c framework to the controller. */
93 struct i2cbus_attach_args {
94 	const char *iba_name;		/* bus name ("iic") */
95 	i2c_tag_t iba_tag;		/* the controller */
96 };
97 
98 /* Used to attach devices on the i2c bus. */
99 struct i2c_attach_args {
100 	i2c_tag_t	ia_tag;		/* our controller */
101 	i2c_addr_t	ia_addr;	/* address of device */
102 	int		ia_size;	/* size (for EEPROMs) */
103 };
104 
105 /*
106  * API presented to i2c controllers.
107  */
108 int	iicbus_print(void *, const char *);
109 
110 #ifdef _I2C_PRIVATE
111 /*
112  * Macros used internally by the i2c framework.
113  */
114 #define	iic_send_start(ic, flags)					\
115 	(*(ic)->ic_send_start)((ic)->ic_cookie, (flags))
116 #define	iic_send_stop(ic, flags)					\
117 	(*(ic)->ic_send_stop)((ic)->ic_cookie, (flags))
118 #define	iic_initiate_xfer(ic, addr, flags)				\
119 	(*(ic)->ic_initiate_xfer)((ic)->ic_cookie, (addr), (flags))
120 
121 #define	iic_read_byte(ic, bytep, flags)					\
122 	(*(ic)->ic_read_byte)((ic)->ic_cookie, (bytep), (flags))
123 #define	iic_write_byte(ic, byte, flags)					\
124 	(*(ic)->ic_write_byte)((ic)->ic_cookie, (byte), (flags))
125 #endif /* _I2C_PRIVATE */
126 
127 /*
128  * Simplified API for clients of the i2c framework.  Definitions
129  * in <dev/i2c/i2c_io.h>.
130  */
131 #define	iic_acquire_bus(ic, flags)					\
132 	(*(ic)->ic_acquire_bus)((ic)->ic_cookie, (flags))
133 #define	iic_release_bus(ic, flags)					\
134 	(*(ic)->ic_release_bus)((ic)->ic_cookie, (flags))
135 
136 int	iic_exec(i2c_tag_t, i2c_op_t, i2c_addr_t, const void *,
137 	    size_t, void *, size_t, int);
138 
139 int	iic_smbus_write_byte(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t, int);
140 int	iic_smbus_read_byte(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t *, int);
141 int	iic_smbus_receive_byte(i2c_tag_t, i2c_addr_t, uint8_t *, int);
142 
143 #endif /* _DEV_I2C_I2CVAR_H_ */
144