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
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
|
/*
* i2c driver for Freescale mx31
*
* (c) 2007 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
*
* (C) Copyright 2008-2009 Freescale Semiconductor, Inc.
*
* 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)
#ifdef CONFIG_MX31
#include <asm/arch/mx31.h>
#include <asm/arch/mx31-regs.h>
#elif defined(CONFIG_MX35)
#include <asm/arch/mx35.h>
#else
#error "Please include specific headfile "
#endif
#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 CONFIG_SYS_I2C_PORT
# define I2C_BASE CONFIG_SYS_I2C_PORT
#else
# error "define CONFIG_SYS_I2C_PORT(I2C base address) to use the I2C driver"
#endif
#define I2C_MAX_TIMEOUT 100000
#define I2C_TIMEOUT_TICKET 1
#undef DEBUG
#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
};
static inline void i2c_reset(void)
{
__REG16(I2C_BASE + I2CR) = 0; /* Reset module */
__REG16(I2C_BASE + I2SR) = 0;
__REG16(I2C_BASE + I2CR) = I2CR_IEN;
}
void i2c_init(int speed, int unused)
{
int freq;
int i;
#ifdef CONFIG_MX31
freq = mx31_get_ipg_clk();
#else
freq = mxc_get_clock(MXC_IPG_PERCLK);
#endif
For (i = 0; i < 0x1f; i++)
if (freq / div[i] <= speed)
break;
DPRINTF("%s: root clock: %d, speed: %d div: %x\n",
__func__, freq, speed, i);
__REG16(I2C_BASE + IFDR) = i;
i2c_reset();
}
static int wait_idle(void)
{
int timeout = I2C_MAX_TIMEOUT;
while ((__REG16(I2C_BASE + I2SR) & I2SR_IBB) && --timeout) {
__REG16(I2C_BASE + I2SR) = 0;
udelay(I2C_TIMEOUT_TICKET);
}
DPRINTF("%s:%x\n", __func__, __REG16(I2C_BASE + I2SR));
return timeout ? timeout : (!(__REG16(I2C_BASE + I2SR) & I2SR_IBB));
}
static int wait_busy(void)
{
int timeout = I2C_MAX_TIMEOUT;
while ((!(__REG16(I2C_BASE + I2SR) & I2SR_IBB) && (--timeout))) {
__REG16(I2C_BASE + I2SR) = 0;
udelay(I2C_TIMEOUT_TICKET);
}
return timeout ? timeout : (__REG16(I2C_BASE + I2SR) & I2SR_IBB);
}
static int wait_complete(void)
{
int timeout = I2C_MAX_TIMEOUT;
while ((!(__REG16(I2C_BASE + I2SR) & I2SR_ICF)) && (--timeout)) {
__REG16(I2C_BASE + I2SR) = 0;
udelay(I2C_TIMEOUT_TICKET);
}
DPRINTF("%s:%x\n", __func__, __REG16(I2C_BASE + I2SR));
{
int i;
for (i = 0; i < 200; i++)
udelay(10);
}
__REG16(I2C_BASE + I2SR) = 0; /* clear interrupt */
return timeout;
}
static int tx_byte(u8 byte)
{
__REG16(I2C_BASE + I2DR) = byte;
if (!wait_complete() || __REG16(I2C_BASE + I2SR) & I2SR_RX_NO_AK) {
DPRINTF("%s:%x <= %x\n", __func__, __REG16(I2C_BASE + I2SR),
byte);
return -1;
}
DPRINTF("%s:%x\n", __func__, byte);
return 0;
}
static int rx_byte(u32 *pdata, int last)
{
if (!wait_complete())
return -1;
if (last)
__REG16(I2C_BASE + I2CR) = I2CR_IEN;
*pdata = __REG16(I2C_BASE + I2DR);
DPRINTF("%s:%x\n", __func__, *pdata);
return 0;
}
int i2c_probe(uchar chip)
{
int ret;
__REG16(I2C_BASE + I2CR) = 0; /* Reset module */
__REG16(I2C_BASE + I2CR) = I2CR_IEN;
for (ret = 0; ret < 1000; ret++)
udelay(1);
__REG16(I2C_BASE + I2CR) = I2CR_IEN | I2CR_MSTA | I2CR_MTX;
ret = tx_byte(chip << 1);
__REG16(I2C_BASE + I2CR) = I2CR_IEN;
return ret;
}
static int i2c_addr(uchar chip, uint addr, int alen)
{
int i, retry = 0;
for (retry = 0; retry < 3; retry++) {
if (wait_idle())
break;
i2c_reset();
for (i = 0; i < I2C_MAX_TIMEOUT; i++)
udelay(I2C_TIMEOUT_TICKET);
}
if (retry >= 3) {
printf("%s:bus is busy(%x)\n",
__func__, __REG16(I2C_BASE + I2SR));
return -1;
}
__REG16(I2C_BASE + I2CR) = I2CR_IEN | I2CR_MSTA | I2CR_MTX;
if (!wait_busy()) {
printf("%s:trigger start fail(%x)\n",
__func__, __REG16(I2C_BASE + I2SR));
return -1;
}
if (tx_byte(chip << 1) || (__REG16(I2C_BASE + I2SR) & I2SR_RX_NO_AK)) {
printf("%s:chip address cycle fail(%x)\n",
__func__, __REG16(I2C_BASE + I2SR));
return -1;
}
while (alen--)
if (tx_byte((addr >> (alen * 8)) & 0xff) ||
(__REG16(I2C_BASE + I2SR) & I2SR_RX_NO_AK)) {
printf("%s:device address cycle fail(%x)\n",
__func__, __REG16(I2C_BASE + I2SR));
return -1;
}
return 0;
}
int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len)
{
int timeout = I2C_MAX_TIMEOUT;
int ret;
DPRINTF("%s chip: 0x%02x addr: 0x%04x alen: %d len: %d\n",
__func__, 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) ||
(__REG16(I2C_BASE + I2SR) & I2SR_RX_NO_AK)) {
printf("%s:Send 2th chip address fail(%x)\n",
__func__, __REG16(I2C_BASE + I2SR));
return -1;
}
__REG16(I2C_BASE + I2CR) = I2CR_IEN | I2CR_MSTA |
((len == 1) ? I2CR_TX_NO_AK : 0);
DPRINTF("CR=%x\n", __REG16(I2C_BASE + I2CR));
ret = __REG16(I2C_BASE + I2DR);
while (len--) {
if (len == 1)
__REG16(I2C_BASE + I2CR) = I2CR_IEN | I2CR_MSTA |
I2CR_TX_NO_AK;
if (rx_byte(&ret, len == 0) < 0) {
printf("Read: rx_byte fail\n");
return -1;
}
*buf++ = ret;
}
while (__REG16(I2C_BASE + I2SR) & I2SR_IBB && --timeout) {
__REG16(I2C_BASE + I2SR) = 0;
udelay(I2C_TIMEOUT_TICKET);
}
if (!timeout) {
printf("%s:trigger stop fail(%x)\n",
__func__, __REG16(I2C_BASE + I2SR));
}
return 0;
}
int i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len)
{
int timeout = I2C_MAX_TIMEOUT;
DPRINTF("%s chip: 0x%02x addr: 0x%04x alen: %d len: %d\n",
__func__, 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(I2C_TIMEOUT_TICKET);
return 0;
}
#endif /* CONFIG_HARD_I2C */
|
