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
|
/* ------------------------------------------------------------------------- */
/* i2c-algo-sibyte.c i2c driver algorithms for bit-shift adapters */
/* ------------------------------------------------------------------------- */
/* Copyright (C) 2001,2002,2003 Broadcom Corporation
Copyright (C) 1995-2000 Simon G. Vogl
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., 675 Mass Ave, Cambridge, MA 02139, USA. */
/* ------------------------------------------------------------------------- */
/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and even
Frodo Looijaard <frodol@dds.nl>. */
/* Ported for SiByte SOCs by Broadcom Corporation. */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <asm/io.h>
#include <asm/sibyte/sb1250_regs.h>
#include <asm/sibyte/sb1250_smbus.h>
#include <linux/i2c.h>
#include <linux/i2c-algo-sibyte.h>
/* ----- global defines ----------------------------------------------- */
#define SMB_CSR(a,r) ((long)(a->reg_base + r))
/* ----- global variables --------------------------------------------- */
/* module parameters:
*/
static int bit_scan=0; /* have a look at what's hanging 'round */
static int smbus_xfer(struct i2c_adapter *i2c_adap, u16 addr,
unsigned short flags, char read_write,
u8 command, int size, union i2c_smbus_data * data)
{
struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data;
int data_bytes = 0;
int error;
while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY)
;
switch (size) {
case I2C_SMBUS_QUICK:
csr_out32((V_SMB_ADDR(addr) | (read_write == I2C_SMBUS_READ ? M_SMB_QDATA : 0) |
V_SMB_TT_QUICKCMD), SMB_CSR(adap, R_SMB_START));
break;
case I2C_SMBUS_BYTE:
if (read_write == I2C_SMBUS_READ) {
csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_RD1BYTE),
SMB_CSR(adap, R_SMB_START));
data_bytes = 1;
} else {
csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD));
csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR1BYTE),
SMB_CSR(adap, R_SMB_START));
}
break;
case I2C_SMBUS_BYTE_DATA:
csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD));
if (read_write == I2C_SMBUS_READ) {
csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD1BYTE),
SMB_CSR(adap, R_SMB_START));
data_bytes = 1;
} else {
csr_out32(V_SMB_LB(data->byte), SMB_CSR(adap, R_SMB_DATA));
csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE),
SMB_CSR(adap, R_SMB_START));
}
break;
case I2C_SMBUS_WORD_DATA:
csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD));
if (read_write == I2C_SMBUS_READ) {
csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD2BYTE),
SMB_CSR(adap, R_SMB_START));
data_bytes = 2;
} else {
csr_out32(V_SMB_LB(data->word & 0xff), SMB_CSR(adap, R_SMB_DATA));
csr_out32(V_SMB_MB(data->word >> 8), SMB_CSR(adap, R_SMB_DATA));
csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE),
SMB_CSR(adap, R_SMB_START));
}
break;
default:
return -1; /* XXXKW better error code? */
}
while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY)
;
error = csr_in32(SMB_CSR(adap, R_SMB_STATUS));
if (error & M_SMB_ERROR) {
/* Clear error bit by writing a 1 */
csr_out32(M_SMB_ERROR, SMB_CSR(adap, R_SMB_STATUS));
return -1; /* XXXKW better error code? */
}
if (data_bytes == 1)
data->byte = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xff;
if (data_bytes == 2)
data->word = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xffff;
return 0;
}
static int algo_control(struct i2c_adapter *adapter,
unsigned int cmd, unsigned long arg)
{
return 0;
}
static u32 bit_func(struct i2c_adapter *adap)
{
return (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA);
}
/* -----exported algorithm data: ------------------------------------- */
static struct i2c_algorithm i2c_sibyte_algo = {
.name = "SiByte algorithm",
.id = I2C_ALGO_SIBYTE,
.smbus_xfer = smbus_xfer,
.algo_control = algo_control, /* ioctl */
.functionality = bit_func,
};
/*
* registering functions to load algorithms at runtime
*/
int i2c_sibyte_add_bus(struct i2c_adapter *i2c_adap, int speed)
{
int i;
struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data;
/* register new adapter to i2c module... */
i2c_adap->id |= i2c_sibyte_algo.id;
i2c_adap->algo = &i2c_sibyte_algo;
/* Set the frequency to 100 kHz */
csr_out32(speed, SMB_CSR(adap,R_SMB_FREQ));
csr_out32(0, SMB_CSR(adap,R_SMB_CONTROL));
/* scan bus */
if (bit_scan) {
union i2c_smbus_data data;
int rc;
printk(KERN_INFO " i2c-algo-sibyte.o: scanning bus %s.\n",
i2c_adap->name);
for (i = 0x00; i < 0x7f; i++) {
/* XXXKW is this a realistic probe? */
rc = smbus_xfer(i2c_adap, i, 0, I2C_SMBUS_READ, 0,
I2C_SMBUS_BYTE_DATA, &data);
if (!rc) {
printk("(%02x)",i);
} else
printk(".");
}
printk("\n");
}
i2c_add_adapter(i2c_adap);
return 0;
}
int i2c_sibyte_del_bus(struct i2c_adapter *adap)
{
int res;
if ((res = i2c_del_adapter(adap)) < 0)
return res;
return 0;
}
int __init i2c_algo_sibyte_init (void)
{
printk("i2c-algo-sibyte.o: i2c SiByte algorithm module\n");
return 0;
}
EXPORT_SYMBOL(i2c_sibyte_add_bus);
EXPORT_SYMBOL(i2c_sibyte_del_bus);
#ifdef MODULE
MODULE_AUTHOR("Kip Walker, Broadcom Corp.");
MODULE_DESCRIPTION("SiByte I2C-Bus algorithm");
MODULE_PARM(bit_scan, "i");
MODULE_PARM_DESC(bit_scan, "Scan for active chips on the bus");
MODULE_LICENSE("GPL");
int init_module(void)
{
return i2c_algo_sibyte_init();
}
void cleanup_module(void)
{
}
#endif
|
