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
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Windfarm PowerMac thermal control. MAX6690 sensor.
*
* Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
*/
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <asm/pmac_low_i2c.h>
#include "windfarm.h"
#define VERSION "1.0"
/* This currently only exports the external temperature sensor,
since that's all the control loops need. */
/* Some MAX6690 register numbers */
#define MAX6690_INTERNAL_TEMP 0
#define MAX6690_EXTERNAL_TEMP 1
struct wf_6690_sensor {
struct i2c_client *i2c;
struct wf_sensor sens;
};
#define wf_to_6690(x) container_of((x), struct wf_6690_sensor, sens)
static int wf_max6690_get(struct wf_sensor *sr, s32 *value)
{
struct wf_6690_sensor *max = wf_to_6690(sr);
s32 data;
if (max->i2c == NULL)
return -ENODEV;
/* chip gets initialized by firmware */
data = i2c_smbus_read_byte_data(max->i2c, MAX6690_EXTERNAL_TEMP);
if (data < 0)
return data;
*value = data << 16;
return 0;
}
static void wf_max6690_release(struct wf_sensor *sr)
{
struct wf_6690_sensor *max = wf_to_6690(sr);
kfree(max);
}
static const struct wf_sensor_ops wf_max6690_ops = {
.get_value = wf_max6690_get,
.release = wf_max6690_release,
.owner = THIS_MODULE,
};
static int wf_max6690_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
const char *name, *loc;
struct wf_6690_sensor *max;
int rc;
loc = of_get_property(client->dev.of_node, "hwsensor-location", NULL);
if (!loc) {
dev_warn(&client->dev, "Missing hwsensor-location property!\n");
return -ENXIO;
}
/*
* We only expose the external temperature register for
* now as this is all we need for our control loops
*/
if (!strcmp(loc, "BACKSIDE") || !strcmp(loc, "SYS CTRLR AMBIENT"))
name = "backside-temp";
else if (!strcmp(loc, "NB Ambient"))
name = "north-bridge-temp";
else if (!strcmp(loc, "GPU Ambient"))
name = "gpu-temp";
else
return -ENXIO;
max = kzalloc(sizeof(struct wf_6690_sensor), GFP_KERNEL);
if (max == NULL) {
printk(KERN_ERR "windfarm: Couldn't create MAX6690 sensor: "
"no memory\n");
return -ENOMEM;
}
max->i2c = client;
max->sens.name = name;
max->sens.ops = &wf_max6690_ops;
i2c_set_clientdata(client, max);
rc = wf_register_sensor(&max->sens);
if (rc)
kfree(max);
return rc;
}
static void wf_max6690_remove(struct i2c_client *client)
{
struct wf_6690_sensor *max = i2c_get_clientdata(client);
max->i2c = NULL;
wf_unregister_sensor(&max->sens);
}
static const struct i2c_device_id wf_max6690_id[] = {
{ "MAC,max6690", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, wf_max6690_id);
static const struct of_device_id wf_max6690_of_id[] = {
{ .compatible = "max6690", },
{ }
};
MODULE_DEVICE_TABLE(of, wf_max6690_of_id);
static struct i2c_driver wf_max6690_driver = {
.driver = {
.name = "wf_max6690",
.of_match_table = wf_max6690_of_id,
},
.probe = wf_max6690_probe,
.remove = wf_max6690_remove,
.id_table = wf_max6690_id,
};
module_i2c_driver(wf_max6690_driver);
MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
MODULE_DESCRIPTION("MAX6690 sensor objects for PowerMac thermal control");
MODULE_LICENSE("GPL");
|
