1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
|
/* $OpenBSD: i2c_exec.c,v 1.3 2015/03/14 03:38:47 jsg Exp $ */
/* $NetBSD: i2c_exec.c,v 1.3 2003/10/29 00:34:58 mycroft 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.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/event.h>
#define _I2C_PRIVATE
#include <dev/i2c/i2cvar.h>
/*
* iic_exec:
*
* Simplified I2C client interface engine.
*
* This and the SMBus routines are the preferred interface for
* client access to I2C/SMBus, since many automated controllers
* do not provide access to the low-level primitives of the I2C
* bus protocol.
*/
int
iic_exec(i2c_tag_t tag, i2c_op_t op, i2c_addr_t addr, const void *vcmd,
size_t cmdlen, void *vbuf, size_t buflen, int flags)
{
const uint8_t *cmd = vcmd;
uint8_t *buf = vbuf;
int error;
size_t len;
/*
* Defer to the controller if it provides an exec function. Use
* it if it does.
*/
if (tag->ic_exec != NULL)
return ((*tag->ic_exec)(tag->ic_cookie, op, addr, cmd,
cmdlen, buf, buflen, flags));
if ((len = cmdlen) != 0) {
if ((error = iic_initiate_xfer(tag, addr, flags)) != 0)
goto bad;
while (len--) {
if ((error = iic_write_byte(tag, *cmd++, flags)) != 0)
goto bad;
}
}
if (I2C_OP_READ_P(op))
flags |= I2C_F_READ;
len = buflen;
while (len--) {
if (len == 0 && I2C_OP_STOP_P(op))
flags |= I2C_F_STOP;
if (I2C_OP_READ_P(op)) {
/* Send REPEATED START. */
if ((len + 1) == buflen &&
(error = iic_initiate_xfer(tag, addr, flags)) != 0)
goto bad;
/* NACK on last byte. */
if (len == 0)
flags |= I2C_F_LAST;
if ((error = iic_read_byte(tag, buf++, flags)) != 0)
goto bad;
} else {
/* Maybe send START. */
if ((len + 1) == buflen && cmdlen == 0 &&
(error = iic_initiate_xfer(tag, addr, flags)) != 0)
goto bad;
if ((error = iic_write_byte(tag, *buf++, flags)) != 0)
goto bad;
}
}
return (0);
bad:
iic_send_stop(tag, flags);
return (error);
}
/*
* iic_smbus_write_byte:
*
* Perform an SMBus "write byte" operation.
*/
int
iic_smbus_write_byte(i2c_tag_t tag, i2c_addr_t addr, uint8_t cmd,
uint8_t val, int flags)
{
return (iic_exec(tag, I2C_OP_WRITE_WITH_STOP, addr,
&cmd, sizeof cmd, &val, sizeof val, flags));
}
/*
* iic_smbus_read_byte:
*
* Perform an SMBus "read byte" operation.
*/
int
iic_smbus_read_byte(i2c_tag_t tag, i2c_addr_t addr, uint8_t cmd,
uint8_t *valp, int flags)
{
return (iic_exec(tag, I2C_OP_READ_WITH_STOP, addr,
&cmd, sizeof cmd, valp, sizeof (*valp), flags));
}
/*
* iic_smbus_receive_byte:
*
* Perform an SMBus "receive byte" operation.
*/
int
iic_smbus_receive_byte(i2c_tag_t tag, i2c_addr_t addr, uint8_t *valp,
int flags)
{
return (iic_exec(tag, I2C_OP_READ_WITH_STOP, addr,
NULL, 0, valp, sizeof (*valp), flags));
}
|
