1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21#include <linux/module.h>
22#include <linux/kernel.h>
23#include <linux/slab.h>
24#include <linux/init.h>
25#include <linux/i2c.h>
26#include <linux/mutex.h>
27
28extern struct i2c_adapter *nforce2_smbus;
29
30static struct i2c_adapter *s4985_adapter;
31static struct i2c_algorithm *s4985_algo;
32
33
34static DEFINE_MUTEX(nforce2_lock);
35
36static s32 nforce2_access_virt0(struct i2c_adapter *adap, u16 addr,
37 unsigned short flags, char read_write,
38 u8 command, int size,
39 union i2c_smbus_data *data)
40{
41 int error;
42
43
44 if ((addr & 0xfc) == 0x50 || (addr & 0xfc) == 0x30
45 || addr == 0x18)
46 return -ENXIO;
47
48 mutex_lock(&nforce2_lock);
49 error = nforce2_smbus->algo->smbus_xfer(adap, addr, flags, read_write,
50 command, size, data);
51 mutex_unlock(&nforce2_lock);
52
53 return error;
54}
55
56
57
58
59
60static u8 last_channels;
61
62static inline s32 nforce2_access_channel(struct i2c_adapter *adap, u16 addr,
63 unsigned short flags, char read_write,
64 u8 command, int size,
65 union i2c_smbus_data *data,
66 u8 channels)
67{
68 int error;
69
70
71 if ((addr & 0xfc) != 0x50 && (addr & 0xfc) != 0x30)
72 return -ENXIO;
73
74 mutex_lock(&nforce2_lock);
75 if (last_channels != channels) {
76 union i2c_smbus_data mplxdata;
77 mplxdata.byte = channels;
78
79 error = nforce2_smbus->algo->smbus_xfer(adap, 0x18, 0,
80 I2C_SMBUS_WRITE, 0x01,
81 I2C_SMBUS_BYTE_DATA,
82 &mplxdata);
83 if (error)
84 goto UNLOCK;
85 last_channels = channels;
86 }
87 error = nforce2_smbus->algo->smbus_xfer(adap, addr, flags, read_write,
88 command, size, data);
89
90UNLOCK:
91 mutex_unlock(&nforce2_lock);
92 return error;
93}
94
95static s32 nforce2_access_virt1(struct i2c_adapter *adap, u16 addr,
96 unsigned short flags, char read_write,
97 u8 command, int size,
98 union i2c_smbus_data *data)
99{
100
101 return nforce2_access_channel(adap, addr, flags, read_write, command,
102 size, data, 0x02);
103}
104
105static s32 nforce2_access_virt2(struct i2c_adapter *adap, u16 addr,
106 unsigned short flags, char read_write,
107 u8 command, int size,
108 union i2c_smbus_data *data)
109{
110
111 return nforce2_access_channel(adap, addr, flags, read_write, command,
112 size, data, 0x04);
113}
114
115static s32 nforce2_access_virt3(struct i2c_adapter *adap, u16 addr,
116 unsigned short flags, char read_write,
117 u8 command, int size,
118 union i2c_smbus_data *data)
119{
120
121 return nforce2_access_channel(adap, addr, flags, read_write, command,
122 size, data, 0x08);
123}
124
125static s32 nforce2_access_virt4(struct i2c_adapter *adap, u16 addr,
126 unsigned short flags, char read_write,
127 u8 command, int size,
128 union i2c_smbus_data *data)
129{
130
131 return nforce2_access_channel(adap, addr, flags, read_write, command,
132 size, data, 0x10);
133}
134
135static int __init nforce2_s4985_init(void)
136{
137 int i, error;
138 union i2c_smbus_data ioconfig;
139
140 if (!nforce2_smbus)
141 return -ENODEV;
142
143
144 ioconfig.byte = 0x00;
145 error = i2c_smbus_xfer(nforce2_smbus, 0x18, 0, I2C_SMBUS_WRITE, 0x03,
146 I2C_SMBUS_BYTE_DATA, &ioconfig);
147 if (error) {
148 dev_err(&nforce2_smbus->dev, "PCA9556 configuration failed\n");
149 error = -EIO;
150 goto ERROR0;
151 }
152
153
154 i2c_del_adapter(nforce2_smbus);
155
156 printk(KERN_INFO "Enabling SMBus multiplexing for Tyan S4985\n");
157
158 s4985_adapter = kcalloc(5, sizeof(struct i2c_adapter), GFP_KERNEL);
159 if (!s4985_adapter) {
160 error = -ENOMEM;
161 goto ERROR1;
162 }
163 s4985_algo = kcalloc(5, sizeof(struct i2c_algorithm), GFP_KERNEL);
164 if (!s4985_algo) {
165 error = -ENOMEM;
166 goto ERROR2;
167 }
168
169
170 s4985_algo[0] = *(nforce2_smbus->algo);
171 s4985_algo[0].smbus_xfer = nforce2_access_virt0;
172 s4985_adapter[0] = *nforce2_smbus;
173 s4985_adapter[0].algo = s4985_algo;
174 s4985_adapter[0].dev.parent = nforce2_smbus->dev.parent;
175 for (i = 1; i < 5; i++) {
176 s4985_algo[i] = *(nforce2_smbus->algo);
177 s4985_adapter[i] = *nforce2_smbus;
178 snprintf(s4985_adapter[i].name, sizeof(s4985_adapter[i].name),
179 "SMBus nForce2 adapter (CPU%d)", i - 1);
180 s4985_adapter[i].algo = s4985_algo + i;
181 s4985_adapter[i].dev.parent = nforce2_smbus->dev.parent;
182 }
183 s4985_algo[1].smbus_xfer = nforce2_access_virt1;
184 s4985_algo[2].smbus_xfer = nforce2_access_virt2;
185 s4985_algo[3].smbus_xfer = nforce2_access_virt3;
186 s4985_algo[4].smbus_xfer = nforce2_access_virt4;
187
188
189 for (i = 0; i < 5; i++) {
190 error = i2c_add_adapter(s4985_adapter + i);
191 if (error) {
192 printk(KERN_ERR "i2c-nforce2-s4985: "
193 "Virtual adapter %d registration "
194 "failed, module not inserted\n", i);
195 for (i--; i >= 0; i--)
196 i2c_del_adapter(s4985_adapter + i);
197 goto ERROR3;
198 }
199 }
200
201 return 0;
202
203ERROR3:
204 kfree(s4985_algo);
205 s4985_algo = NULL;
206ERROR2:
207 kfree(s4985_adapter);
208 s4985_adapter = NULL;
209ERROR1:
210
211 i2c_add_adapter(nforce2_smbus);
212ERROR0:
213 return error;
214}
215
216static void __exit nforce2_s4985_exit(void)
217{
218 if (s4985_adapter) {
219 int i;
220
221 for (i = 0; i < 5; i++)
222 i2c_del_adapter(s4985_adapter+i);
223 kfree(s4985_adapter);
224 s4985_adapter = NULL;
225 }
226 kfree(s4985_algo);
227 s4985_algo = NULL;
228
229
230 if (i2c_add_adapter(nforce2_smbus))
231 printk(KERN_ERR "i2c-nforce2-s4985: "
232 "Physical bus restoration failed\n");
233}
234
235MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
236MODULE_DESCRIPTION("S4985 SMBus multiplexing");
237MODULE_LICENSE("GPL");
238
239module_init(nforce2_s4985_init);
240module_exit(nforce2_s4985_exit);
241