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10#include <linux/types.h>
11#include <linux/errno.h>
12#include <linux/kernel.h>
13#include <linux/delay.h>
14#include <linux/slab.h>
15#include <linux/init.h>
16#include <linux/wait.h>
17#include <linux/i2c.h>
18#include <asm/prom.h>
19#include <asm/machdep.h>
20#include <asm/io.h>
21#include <asm/sections.h>
22#include <asm/pmac_low_i2c.h>
23
24#include "windfarm.h"
25
26#define VERSION "1.0"
27
28#undef DEBUG
29
30#ifdef DEBUG
31#define DBG(args...) printk(args)
32#else
33#define DBG(args...) do { } while(0)
34#endif
35
36struct wf_lm87_sensor {
37 struct i2c_client *i2c;
38 struct wf_sensor sens;
39};
40#define wf_to_lm87(c) container_of(c, struct wf_lm87_sensor, sens)
41
42
43static int wf_lm87_read_reg(struct i2c_client *chip, int reg)
44{
45 int rc, tries = 0;
46 u8 buf;
47
48 for (;;) {
49
50 buf = (u8)reg;
51 rc = i2c_master_send(chip, &buf, 1);
52 if (rc <= 0)
53 goto error;
54 rc = i2c_master_recv(chip, &buf, 1);
55 if (rc <= 0)
56 goto error;
57 return (int)buf;
58 error:
59 DBG("wf_lm87: Error reading LM87, retrying...\n");
60 if (++tries > 10) {
61 printk(KERN_ERR "wf_lm87: Error reading LM87 !\n");
62 return -EIO;
63 }
64 msleep(10);
65 }
66}
67
68static int wf_lm87_get(struct wf_sensor *sr, s32 *value)
69{
70 struct wf_lm87_sensor *lm = sr->priv;
71 s32 temp;
72
73 if (lm->i2c == NULL)
74 return -ENODEV;
75
76#define LM87_INT_TEMP 0x27
77
78
79 temp = wf_lm87_read_reg(lm->i2c, LM87_INT_TEMP);
80 if (temp < 0)
81 return temp;
82 *value = temp << 16;
83
84 return 0;
85}
86
87static void wf_lm87_release(struct wf_sensor *sr)
88{
89 struct wf_lm87_sensor *lm = wf_to_lm87(sr);
90
91 kfree(lm);
92}
93
94static const struct wf_sensor_ops wf_lm87_ops = {
95 .get_value = wf_lm87_get,
96 .release = wf_lm87_release,
97 .owner = THIS_MODULE,
98};
99
100static int wf_lm87_probe(struct i2c_client *client,
101 const struct i2c_device_id *id)
102{
103 struct wf_lm87_sensor *lm;
104 const char *name = NULL, *loc;
105 struct device_node *np = NULL;
106 int rc;
107
108
109
110
111
112
113 while ((np = of_get_next_child(client->dev.of_node, np)) != NULL) {
114 if (strcmp(np->name, "int-temp"))
115 continue;
116 loc = of_get_property(np, "location", NULL);
117 if (!loc)
118 continue;
119 if (strstr(loc, "DIMM"))
120 name = "dimms-temp";
121 else if (strstr(loc, "Processors"))
122 name = "between-cpus-temp";
123 if (name) {
124 of_node_put(np);
125 break;
126 }
127 }
128 if (!name) {
129 pr_warning("wf_lm87: Unsupported sensor %pOF\n",
130 client->dev.of_node);
131 return -ENODEV;
132 }
133
134 lm = kzalloc(sizeof(struct wf_lm87_sensor), GFP_KERNEL);
135 if (lm == NULL)
136 return -ENODEV;
137
138 lm->i2c = client;
139 lm->sens.name = name;
140 lm->sens.ops = &wf_lm87_ops;
141 lm->sens.priv = lm;
142 i2c_set_clientdata(client, lm);
143
144 rc = wf_register_sensor(&lm->sens);
145 if (rc)
146 kfree(lm);
147 return rc;
148}
149
150static int wf_lm87_remove(struct i2c_client *client)
151{
152 struct wf_lm87_sensor *lm = i2c_get_clientdata(client);
153
154 DBG("wf_lm87: i2c detatch called for %s\n", lm->sens.name);
155
156
157 lm->i2c = NULL;
158
159
160 wf_unregister_sensor(&lm->sens);
161
162 return 0;
163}
164
165static const struct i2c_device_id wf_lm87_id[] = {
166 { "MAC,lm87cimt", 0 },
167 { }
168};
169MODULE_DEVICE_TABLE(i2c, wf_lm87_id);
170
171static struct i2c_driver wf_lm87_driver = {
172 .driver = {
173 .name = "wf_lm87",
174 },
175 .probe = wf_lm87_probe,
176 .remove = wf_lm87_remove,
177 .id_table = wf_lm87_id,
178};
179
180static int __init wf_lm87_sensor_init(void)
181{
182
183 if (!of_machine_is_compatible("RackMac3,1"))
184 return -ENODEV;
185
186 return i2c_add_driver(&wf_lm87_driver);
187}
188
189static void __exit wf_lm87_sensor_exit(void)
190{
191 i2c_del_driver(&wf_lm87_driver);
192}
193
194
195module_init(wf_lm87_sensor_init);
196module_exit(wf_lm87_sensor_exit);
197
198MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
199MODULE_DESCRIPTION("LM87 sensor objects for PowerMacs thermal control");
200MODULE_LICENSE("GPL");
201
202
