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
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
|
/*
* i2c driver for Freescale mx31
*
* (c) 2007 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
*
* See file CREDITS for list of people who contributed to this
* 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; either version 2 of
* the License, or (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#if defined(CONFIG_HARD_I2C)
#include <asm/arch/mx31.h>
#include <asm/arch/mx31-regs.h>
#define IADR 0x00
#define IFDR 0x04
#define I2CR 0x08
#define I2SR 0x0c
#define I2DR 0x10
#define I2CR_IEN (1 << 7)
#define I2CR_IIEN (1 << 6)
#define I2CR_MSTA (1 << 5)
#define I2CR_MTX (1 << 4)
#define I2CR_TX_NO_AK (1 << 3)
#define I2CR_RSTA (1 << 2)
#define I2SR_ICF (1 << 7)
#define I2SR_IBB (1 << 5)
#define I2SR_IIF (1 << 1)
#define I2SR_RX_NO_AK (1 << 0)
#ifdef CFG_I2C_MX31_PORT1
#define I2C_BASE 0x43f80000
#elif defined (CFG_I2C_MX31_PORT2)
#define I2C_BASE 0x43f98000
#elif defined (CFG_I2C_MX31_PORT3)
#define I2C_BASE 0x43f84000
#else
#error "define CFG_I2C_MX31_PORTx to use the mx31 I2C driver"
#endif
#ifdef DEBUG
#define DPRINTF(args...) printf(args)
#else
#define DPRINTF(args...)
#endif
static u16 div[] = { 30, 32, 36, 42, 48, 52, 60, 72, 80, 88, 104, 128, 144,
160, 192, 240, 288, 320, 384, 480, 576, 640, 768, 960,
1152, 1280, 1536, 1920, 2304, 2560, 3072, 3840};
void i2c_init(int speed, int unused)
{
int freq = mx31_get_ipg_clk();
int i;
for (i = 0; i < 0x1f; i++)
if (freq / div[i] <= speed)
break;
DPRINTF("%s: speed: %d\n",__FUNCTION__, speed);
__REG16(I2C_BASE + I2CR) = 0; /* Reset module */
__REG16(I2C_BASE + IFDR) = i;
__REG16(I2C_BASE + I2CR) = I2CR_IEN;
__REG16(I2C_BASE + I2SR) = 0;
}
static int wait_busy(void)
{
int timeout = 10000;
while (!(__REG16(I2C_BASE + I2SR) & I2SR_IIF) && --timeout)
udelay(1);
__REG16(I2C_BASE + I2SR) = 0; /* clear interrupt */
return timeout;
}
static int tx_byte(u8 byte)
{
__REG16(I2C_BASE + I2DR) = byte;
if (!wait_busy() || __REG16(I2C_BASE + I2SR) & I2SR_RX_NO_AK)
return -1;
return 0;
}
static int rx_byte(void)
{
if (!wait_busy())
return -1;
return __REG16(I2C_BASE + I2DR);
}
int i2c_probe(uchar chip)
{
int ret;
__REG16(I2C_BASE + I2CR) = 0; /* Reset module */
__REG16(I2C_BASE + I2CR) = I2CR_IEN;
__REG16(I2C_BASE + I2CR) = I2CR_IEN | I2CR_MSTA | I2CR_MTX;
ret = tx_byte(chip << 1);
__REG16(I2C_BASE + I2CR) = I2CR_IEN | I2CR_MTX;
return ret;
}
static int i2c_addr(uchar chip, uint addr, int alen)
{
__REG16(I2C_BASE + I2SR) = 0; /* clear interrupt */
__REG16(I2C_BASE + I2CR) = I2CR_IEN | I2CR_MSTA | I2CR_MTX;
if (tx_byte(chip << 1))
return -1;
while (alen--)
if (tx_byte((addr >> (alen * 8)) & 0xff))
return -1;
return 0;
}
int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len)
{
int timeout = 10000;
int ret;
DPRINTF("%s chip: 0x%02x addr: 0x%04x alen: %d len: %d\n",__FUNCTION__, chip, addr, alen, len);
if (i2c_addr(chip, addr, alen)) {
printf("i2c_addr failed\n");
return -1;
}
__REG16(I2C_BASE + I2CR) = I2CR_IEN | I2CR_MSTA | I2CR_MTX | I2CR_RSTA;
if (tx_byte(chip << 1 | 1))
return -1;
__REG16(I2C_BASE + I2CR) = I2CR_IEN | I2CR_MSTA | ((len == 1) ? I2CR_TX_NO_AK : 0);
ret = __REG16(I2C_BASE + I2DR);
while (len--) {
if ((ret = rx_byte()) < 0)
return -1;
*buf++ = ret;
if (len <= 1)
__REG16(I2C_BASE + I2CR) = I2CR_IEN | I2CR_MSTA | I2CR_TX_NO_AK;
}
wait_busy();
__REG16(I2C_BASE + I2CR) = I2CR_IEN;
while (__REG16(I2C_BASE + I2SR) & I2SR_IBB && --timeout)
udelay(1);
return 0;
}
int i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len)
{
int timeout = 10000;
DPRINTF("%s chip: 0x%02x addr: 0x%04x alen: %d len: %d\n",__FUNCTION__, chip, addr, alen, len);
if (i2c_addr(chip, addr, alen))
return -1;
while (len--)
if (tx_byte(*buf++))
return -1;
__REG16(I2C_BASE + I2CR) = I2CR_IEN;
while (__REG16(I2C_BASE + I2SR) & I2SR_IBB && --timeout)
udelay(1);
return 0;
}
#endif /* CONFIG_HARD_I2C */
|
