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
|
/*
* Windfarm PowerMac thermal control. LM75 sensor
*
* (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
* <benh@kernel.crashing.org>
*
* Released under the term of the GNU GPL v2.
*/
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/wait.h>
#include <linux/i2c.h>
#include <linux/i2c-dev.h>
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/sections.h>
#include <asm/pmac_low_i2c.h>
#include "windfarm.h"
#define VERSION "0.1"
#undef DEBUG
#ifdef DEBUG
#define DBG(args...) printk(args)
#else
#define DBG(args...) do { } while(0)
#endif
struct wf_lm75_sensor {
int ds1775 : 1;
int inited : 1;
struct i2c_client i2c;
struct wf_sensor sens;
};
#define wf_to_lm75(c) container_of(c, struct wf_lm75_sensor, sens)
#define i2c_to_lm75(c) container_of(c, struct wf_lm75_sensor, i2c)
static int wf_lm75_attach(struct i2c_adapter *adapter);
static int wf_lm75_detach(struct i2c_client *client);
static struct i2c_driver wf_lm75_driver = {
.driver = {
.name = "wf_lm75",
},
.attach_adapter = wf_lm75_attach,
.detach_client = wf_lm75_detach,
};
static int wf_lm75_get(struct wf_sensor *sr, s32 *value)
{
struct wf_lm75_sensor *lm = wf_to_lm75(sr);
s32 data;
if (lm->i2c.adapter == NULL)
return -ENODEV;
/* Init chip if necessary */
if (!lm->inited) {
u8 cfg_new, cfg = (u8)i2c_smbus_read_byte_data(&lm->i2c, 1);
DBG("wf_lm75: Initializing %s, cfg was: %02x\n",
sr->name, cfg);
/* clear shutdown bit, keep other settings as left by
* the firmware for now
*/
cfg_new = cfg & ~0x01;
i2c_smbus_write_byte_data(&lm->i2c, 1, cfg_new);
lm->inited = 1;
/* If we just powered it up, let's wait 200 ms */
msleep(200);
}
/* Read temperature register */
data = (s32)le16_to_cpu(i2c_smbus_read_word_data(&lm->i2c, 0));
data <<= 8;
*value = data;
return 0;
}
static void wf_lm75_release(struct wf_sensor *sr)
{
struct wf_lm75_sensor *lm = wf_to_lm75(sr);
/* check if client is registered and detach from i2c */
if (lm->i2c.adapter) {
i2c_detach_client(&lm->i2c);
lm->i2c.adapter = NULL;
}
kfree(lm);
}
static struct wf_sensor_ops wf_lm75_ops = {
.get_value = wf_lm75_get,
.release = wf_lm75_release,
.owner = THIS_MODULE,
};
static struct wf_lm75_sensor *wf_lm75_create(struct i2c_adapter *adapter,
u8 addr, int ds1775,
const char *loc)
{
struct wf_lm75_sensor *lm;
DBG("wf_lm75: creating %s device at address 0x%02x\n",
ds1775 ? "ds1775" : "lm75", addr);
lm = kmalloc(sizeof(struct wf_lm75_sensor), GFP_KERNEL);
if (lm == NULL)
return NULL;
memset(lm, 0, sizeof(struct wf_lm75_sensor));
/* Usual rant about sensor names not beeing very consistent in
* the device-tree, oh well ...
* Add more entries below as you deal with more setups
*/
if (!strcmp(loc, "Hard drive") || !strcmp(loc, "DRIVE BAY"))
lm->sens.name = "hd-temp";
else
goto fail;
lm->inited = 0;
lm->sens.ops = &wf_lm75_ops;
lm->ds1775 = ds1775;
lm->i2c.addr = (addr >> 1) & 0x7f;
lm->i2c.adapter = adapter;
lm->i2c.driver = &wf_lm75_driver;
strncpy(lm->i2c.name, lm->sens.name, I2C_NAME_SIZE-1);
if (i2c_attach_client(&lm->i2c)) {
printk(KERN_ERR "windfarm: failed to attach %s %s to i2c\n",
ds1775 ? "ds1775" : "lm75", lm->i2c.name);
goto fail;
}
if (wf_register_sensor(&lm->sens)) {
i2c_detach_client(&lm->i2c);
goto fail;
}
return lm;
fail:
kfree(lm);
return NULL;
}
static int wf_lm75_attach(struct i2c_adapter *adapter)
{
struct device_node *busnode, *dev;
struct pmac_i2c_bus *bus;
DBG("wf_lm75: adapter %s detected\n", adapter->name);
bus = pmac_i2c_adapter_to_bus(adapter);
if (bus == NULL)
return -ENODEV;
busnode = pmac_i2c_get_bus_node(bus);
DBG("wf_lm75: bus found, looking for device...\n");
/* Now look for lm75(s) in there */
for (dev = NULL;
(dev = of_get_next_child(busnode, dev)) != NULL;) {
const char *loc =
get_property(dev, "hwsensor-location", NULL);
u32 *reg = (u32 *)get_property(dev, "reg", NULL);
DBG(" dev: %s... (loc: %p, reg: %p)\n", dev->name, loc, reg);
if (loc == NULL || reg == NULL)
continue;
/* real lm75 */
if (device_is_compatible(dev, "lm75"))
wf_lm75_create(adapter, *reg, 0, loc);
/* ds1775 (compatible, better resolution */
else if (device_is_compatible(dev, "ds1775"))
wf_lm75_create(adapter, *reg, 1, loc);
}
return 0;
}
static int wf_lm75_detach(struct i2c_client *client)
{
struct wf_lm75_sensor *lm = i2c_to_lm75(client);
DBG("wf_lm75: i2c detatch called for %s\n", lm->sens.name);
/* Mark client detached */
lm->i2c.adapter = NULL;
/* release sensor */
wf_unregister_sensor(&lm->sens);
return 0;
}
static int __init wf_lm75_sensor_init(void)
{
return i2c_add_driver(&wf_lm75_driver);
}
static void __exit wf_lm75_sensor_exit(void)
{
i2c_del_driver(&wf_lm75_driver);
}
module_init(wf_lm75_sensor_init);
module_exit(wf_lm75_sensor_exit);
MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
MODULE_DESCRIPTION("LM75 sensor objects for PowerMacs thermal control");
MODULE_LICENSE("GPL");
|
