Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / macintosh / windfarm_max6690_sensor.c
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1/*
2 * Windfarm PowerMac thermal control. MAX6690 sensor.
3 *
4 * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
5 *
6 * Use and redistribute under the terms of the GNU GPL v2.
7 */
8#include <linux/types.h>
9#include <linux/errno.h>
10#include <linux/kernel.h>
11#include <linux/init.h>
12#include <linux/slab.h>
13#include <linux/i2c.h>
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14#include <asm/prom.h>
15#include <asm/pmac_low_i2c.h>
16
17#include "windfarm.h"
18
b55fafc5 19#define VERSION "0.2"
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20
21/* This currently only exports the external temperature sensor,
22 since that's all the control loops need. */
23
24/* Some MAX6690 register numbers */
25#define MAX6690_INTERNAL_TEMP 0
26#define MAX6690_EXTERNAL_TEMP 1
27
28struct wf_6690_sensor {
351ca3e3 29 struct i2c_client *i2c;
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30 struct wf_sensor sens;
31};
32
33#define wf_to_6690(x) container_of((x), struct wf_6690_sensor, sens)
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34
35static int wf_max6690_get(struct wf_sensor *sr, s32 *value)
36{
37 struct wf_6690_sensor *max = wf_to_6690(sr);
38 s32 data;
39
351ca3e3 40 if (max->i2c == NULL)
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41 return -ENODEV;
42
43 /* chip gets initialized by firmware */
351ca3e3 44 data = i2c_smbus_read_byte_data(max->i2c, MAX6690_EXTERNAL_TEMP);
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45 if (data < 0)
46 return data;
47 *value = data << 16;
48 return 0;
49}
50
51static void wf_max6690_release(struct wf_sensor *sr)
52{
53 struct wf_6690_sensor *max = wf_to_6690(sr);
54
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55 kfree(max);
56}
57
58static struct wf_sensor_ops wf_max6690_ops = {
59 .get_value = wf_max6690_get,
60 .release = wf_max6690_release,
61 .owner = THIS_MODULE,
62};
63
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64static int wf_max6690_probe(struct i2c_client *client,
65 const struct i2c_device_id *id)
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66{
67 struct wf_6690_sensor *max;
351ca3e3 68 int rc;
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69
70 max = kzalloc(sizeof(struct wf_6690_sensor), GFP_KERNEL);
71 if (max == NULL) {
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72 printk(KERN_ERR "windfarm: Couldn't create MAX6690 sensor: "
73 "no memory\n");
74 return -ENOMEM;
75 }
76
77 max->i2c = client;
78 max->sens.name = client->dev.platform_data;
79 max->sens.ops = &wf_max6690_ops;
80 i2c_set_clientdata(client, max);
81
82 rc = wf_register_sensor(&max->sens);
83 if (rc) {
84 i2c_set_clientdata(client, NULL);
85 kfree(max);
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86 }
87
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88 return rc;
89}
90
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91static struct i2c_driver wf_max6690_driver;
92
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93static struct i2c_client *wf_max6690_create(struct i2c_adapter *adapter,
94 u8 addr, const char *loc)
95{
96 struct i2c_board_info info;
97 struct i2c_client *client;
98 char *name;
99
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100 if (!strcmp(loc, "BACKSIDE"))
101 name = "backside-temp";
102 else if (!strcmp(loc, "NB Ambient"))
103 name = "north-bridge-temp";
104 else if (!strcmp(loc, "GPU Ambient"))
105 name = "gpu-temp";
106 else
107 goto fail;
108
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109 memset(&info, 0, sizeof(struct i2c_board_info));
110 info.addr = addr >> 1;
111 info.platform_data = name;
112 strlcpy(info.type, "wf_max6690", I2C_NAME_SIZE);
ac171c46 113
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114 client = i2c_new_device(adapter, &info);
115 if (client == NULL) {
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116 printk(KERN_ERR "windfarm: failed to attach MAX6690 sensor\n");
117 goto fail;
118 }
119
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120 /*
121 * Let i2c-core delete that device on driver removal.
122 * This is safe because i2c-core holds the core_lock mutex for us.
123 */
6f6b35e1 124 list_add_tail(&client->detected, &wf_max6690_driver.clients);
351ca3e3 125 return client;
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126
127 fail:
351ca3e3 128 return NULL;
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129}
130
131static int wf_max6690_attach(struct i2c_adapter *adapter)
132{
133 struct device_node *busnode, *dev = NULL;
134 struct pmac_i2c_bus *bus;
135 const char *loc;
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136
137 bus = pmac_i2c_adapter_to_bus(adapter);
138 if (bus == NULL)
139 return -ENODEV;
140 busnode = pmac_i2c_get_bus_node(bus);
141
142 while ((dev = of_get_next_child(busnode, dev)) != NULL) {
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143 u8 addr;
144
145 /* We must re-match the adapter in order to properly check
146 * the channel on multibus setups
147 */
148 if (!pmac_i2c_match_adapter(dev, adapter))
149 continue;
55b61fec 150 if (!of_device_is_compatible(dev, "max6690"))
ac171c46 151 continue;
b55fafc5 152 addr = pmac_i2c_get_dev_addr(dev);
01b2726d 153 loc = of_get_property(dev, "hwsensor-location", NULL);
b55fafc5 154 if (loc == NULL || addr == 0)
ac171c46 155 continue;
b55fafc5 156 printk("found max6690, loc=%s addr=0x%02x\n", loc, addr);
80ff974d 157 wf_max6690_create(adapter, addr, loc);
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158 }
159
160 return 0;
161}
162
351ca3e3 163static int wf_max6690_remove(struct i2c_client *client)
ac171c46 164{
351ca3e3 165 struct wf_6690_sensor *max = i2c_get_clientdata(client);
ac171c46 166
351ca3e3 167 max->i2c = NULL;
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168 wf_unregister_sensor(&max->sens);
169
170 return 0;
171}
172
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173static const struct i2c_device_id wf_max6690_id[] = {
174 { "wf_max6690", 0 },
175 { }
176};
177
178static struct i2c_driver wf_max6690_driver = {
179 .driver = {
180 .name = "wf_max6690",
181 },
182 .attach_adapter = wf_max6690_attach,
183 .probe = wf_max6690_probe,
184 .remove = wf_max6690_remove,
185 .id_table = wf_max6690_id,
186};
187
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188static int __init wf_max6690_sensor_init(void)
189{
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190 /* Don't register on old machines that use therm_pm72 for now */
191 if (machine_is_compatible("PowerMac7,2") ||
192 machine_is_compatible("PowerMac7,3") ||
193 machine_is_compatible("RackMac3,1"))
194 return -ENODEV;
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195 return i2c_add_driver(&wf_max6690_driver);
196}
197
198static void __exit wf_max6690_sensor_exit(void)
199{
200 i2c_del_driver(&wf_max6690_driver);
201}
202
203module_init(wf_max6690_sensor_init);
204module_exit(wf_max6690_sensor_exit);
205
206MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
207MODULE_DESCRIPTION("MAX6690 sensor objects for PowerMac thermal control");
208MODULE_LICENSE("GPL");