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
|
/*
* This file is part of the coreboot project.
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef _DEVICE_I2C_SIMPLE_H_
#define _DEVICE_I2C_SIMPLE_H_
#include <commonlib/helpers.h>
#include <device/i2c.h>
int platform_i2c_transfer(unsigned int bus, struct i2c_msg *segments,
int count);
#define SOFTWARE_I2C_MAX_BUS 10 /* increase as necessary */
struct software_i2c_ops {
void (*set_sda)(unsigned int bus, int high);
void (*set_scl)(unsigned int bus, int high);
int (*get_sda)(unsigned int bus);
int (*get_scl)(unsigned int bus);
};
extern struct software_i2c_ops *software_i2c[];
int software_i2c_transfer(unsigned int bus, struct i2c_msg *segments,
int count);
void software_i2c_wedge_ack(unsigned int bus, u8 slave);
void software_i2c_wedge_read(unsigned int bus, u8 slave, u8 reg, int bit_count);
void software_i2c_wedge_write(unsigned int bus, u8 slave, u8 reg,
int bit_count);
int i2c_read_field(unsigned int bus, uint8_t slave, uint8_t reg, uint8_t *data,
uint8_t mask, uint8_t shift);
int i2c_write_field(unsigned int bus, uint8_t slave, uint8_t reg, uint8_t data,
uint8_t mask, uint8_t shift);
/*
* software_i2c is supposed to be a debug feature. It's usually not compiled in,
* but when it is it can be dynamically enabled at runtime for certain busses.
* Need this ugly stub to arbitrate since I2C device drivers hardcode
* 'i2c_transfer()' as their entry point.
*/
static inline int i2c_transfer(unsigned int bus, struct i2c_msg *segments,
int count)
{
if (CONFIG(SOFTWARE_I2C))
if (bus < SOFTWARE_I2C_MAX_BUS && software_i2c[bus])
return software_i2c_transfer(bus, segments, count);
return platform_i2c_transfer(bus, segments, count);
}
/*
* Read a raw chunk of data in one segment and one frame.
*
* [start][slave addr][r][data][stop]
*/
static inline int i2c_read_raw(unsigned int bus, uint8_t slave, uint8_t *data,
int len)
{
struct i2c_msg seg = {
.flags = I2C_M_RD, .slave = slave, .buf = data, .len = len
};
return i2c_transfer(bus, &seg, 1);
}
/*
* Write a raw chunk of data in one segment and one frame.
*
* [start][slave addr][w][data][stop]
*/
static inline int i2c_write_raw(unsigned int bus, uint8_t slave, uint8_t *data,
int len)
{
struct i2c_msg seg = {
.flags = 0, .slave = slave, .buf = data, .len = len
};
return i2c_transfer(bus, &seg, 1);
}
/**
* Read multi-bytes with two segments in one frame
*
* [start][slave addr][w][register addr][start][slave addr][r][data...][stop]
*/
static inline int i2c_read_bytes(unsigned int bus, uint8_t slave, uint8_t reg,
uint8_t *data, int len)
{
struct i2c_msg seg[2];
seg[0].flags = 0;
seg[0].slave = slave;
seg[0].buf = ®
seg[0].len = 1;
seg[1].flags = I2C_M_RD;
seg[1].slave = slave;
seg[1].buf = data;
seg[1].len = len;
return i2c_transfer(bus, seg, ARRAY_SIZE(seg));
}
/**
* Read a byte with two segments in one frame
*
* [start][slave addr][w][register addr][start][slave addr][r][data][stop]
*/
static inline int i2c_readb(unsigned int bus, uint8_t slave, uint8_t reg,
uint8_t *data)
{
struct i2c_msg seg[2];
seg[0].flags = 0;
seg[0].slave = slave;
seg[0].buf = ®
seg[0].len = 1;
seg[1].flags = I2C_M_RD;
seg[1].slave = slave;
seg[1].buf = data;
seg[1].len = 1;
return i2c_transfer(bus, seg, ARRAY_SIZE(seg));
}
/**
* Write a byte with one segment in one frame.
*
* [start][slave addr][w][register addr][data][stop]
*/
static inline int i2c_writeb(unsigned int bus, uint8_t slave, uint8_t reg,
uint8_t data)
{
struct i2c_msg seg;
uint8_t buf[] = {reg, data};
seg.flags = 0;
seg.slave = slave;
seg.buf = buf;
seg.len = ARRAY_SIZE(buf);
return i2c_transfer(bus, &seg, 1);
}
#endif /* _DEVICE_I2C_SIMPLE_H_ */
|
