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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>
14#include <asm/prom.h>
15#include <asm/pmac_low_i2c.h>
16
17#include "windfarm.h"
18
19#define VERSION "0.2"
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 {
29 struct i2c_client *i2c;
30 struct wf_sensor sens;
31};
32
33#define wf_to_6690(x) container_of((x), struct wf_6690_sensor, sens)
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
40 if (max->i2c == NULL)
41 return -ENODEV;
42
43 /* chip gets initialized by firmware */
44 data = i2c_smbus_read_byte_data(max->i2c, MAX6690_EXTERNAL_TEMP);
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
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
64static int wf_max6690_probe(struct i2c_client *client,
65 const struct i2c_device_id *id)
66{
67 struct wf_6690_sensor *max;
68 int rc;
69
70 max = kzalloc(sizeof(struct wf_6690_sensor), GFP_KERNEL);
71 if (max == NULL) {
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 kfree(max);
85 }
86
87 return rc;
88}
89
90static struct i2c_driver wf_max6690_driver;
91
92static struct i2c_client *wf_max6690_create(struct i2c_adapter *adapter,
93 u8 addr, const char *loc)
94{
95 struct i2c_board_info info;
96 struct i2c_client *client;
97 char *name;
98
99 if (!strcmp(loc, "BACKSIDE"))
100 name = "backside-temp";
101 else if (!strcmp(loc, "NB Ambient"))
102 name = "north-bridge-temp";
103 else if (!strcmp(loc, "GPU Ambient"))
104 name = "gpu-temp";
105 else
106 goto fail;
107
108 memset(&info, 0, sizeof(struct i2c_board_info));
109 info.addr = addr >> 1;
110 info.platform_data = name;
111 strlcpy(info.type, "wf_max6690", I2C_NAME_SIZE);
112
113 client = i2c_new_device(adapter, &info);
114 if (client == NULL) {
115 printk(KERN_ERR "windfarm: failed to attach MAX6690 sensor\n");
116 goto fail;
117 }
118
119 /*
120 * Let i2c-core delete that device on driver removal.
121 * This is safe because i2c-core holds the core_lock mutex for us.
122 */
123 list_add_tail(&client->detected, &wf_max6690_driver.clients);
124 return client;
125
126 fail:
127 return NULL;
128}
129
130static int wf_max6690_attach(struct i2c_adapter *adapter)
131{
132 struct device_node *busnode, *dev = NULL;
133 struct pmac_i2c_bus *bus;
134 const char *loc;
135
136 bus = pmac_i2c_adapter_to_bus(adapter);
137 if (bus == NULL)
138 return -ENODEV;
139 busnode = pmac_i2c_get_bus_node(bus);
140
141 while ((dev = of_get_next_child(busnode, dev)) != NULL) {
142 u8 addr;
143
144 /* We must re-match the adapter in order to properly check
145 * the channel on multibus setups
146 */
147 if (!pmac_i2c_match_adapter(dev, adapter))
148 continue;
149 if (!of_device_is_compatible(dev, "max6690"))
150 continue;
151 addr = pmac_i2c_get_dev_addr(dev);
152 loc = of_get_property(dev, "hwsensor-location", NULL);
153 if (loc == NULL || addr == 0)
154 continue;
155 printk("found max6690, loc=%s addr=0x%02x\n", loc, addr);
156 wf_max6690_create(adapter, addr, loc);
157 }
158
159 return 0;
160}
161
162static int wf_max6690_remove(struct i2c_client *client)
163{
164 struct wf_6690_sensor *max = i2c_get_clientdata(client);
165
166 max->i2c = NULL;
167 wf_unregister_sensor(&max->sens);
168
169 return 0;
170}
171
172static const struct i2c_device_id wf_max6690_id[] = {
173 { "wf_max6690", 0 },
174 { }
175};
176
177static struct i2c_driver wf_max6690_driver = {
178 .driver = {
179 .name = "wf_max6690",
180 },
181 .attach_adapter = wf_max6690_attach,
182 .probe = wf_max6690_probe,
183 .remove = wf_max6690_remove,
184 .id_table = wf_max6690_id,
185};
186
187static int __init wf_max6690_sensor_init(void)
188{
189 /* Don't register on old machines that use therm_pm72 for now */
190 if (of_machine_is_compatible("PowerMac7,2") ||
191 of_machine_is_compatible("PowerMac7,3") ||
192 of_machine_is_compatible("RackMac3,1"))
193 return -ENODEV;
194 return i2c_add_driver(&wf_max6690_driver);
195}
196
197static void __exit wf_max6690_sensor_exit(void)
198{
199 i2c_del_driver(&wf_max6690_driver);
200}
201
202module_init(wf_max6690_sensor_init);
203module_exit(wf_max6690_sensor_exit);
204
205MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
206MODULE_DESCRIPTION("MAX6690 sensor objects for PowerMac thermal control");
207MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Windfarm PowerMac thermal control. MAX6690 sensor.
4 *
5 * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
6 */
7#include <linux/types.h>
8#include <linux/errno.h>
9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/slab.h>
12#include <linux/i2c.h>
13
14#include <asm/pmac_low_i2c.h>
15
16#include "windfarm.h"
17
18#define VERSION "1.0"
19
20/* This currently only exports the external temperature sensor,
21 since that's all the control loops need. */
22
23/* Some MAX6690 register numbers */
24#define MAX6690_INTERNAL_TEMP 0
25#define MAX6690_EXTERNAL_TEMP 1
26
27struct wf_6690_sensor {
28 struct i2c_client *i2c;
29 struct wf_sensor sens;
30};
31
32#define wf_to_6690(x) container_of((x), struct wf_6690_sensor, sens)
33
34static int wf_max6690_get(struct wf_sensor *sr, s32 *value)
35{
36 struct wf_6690_sensor *max = wf_to_6690(sr);
37 s32 data;
38
39 if (max->i2c == NULL)
40 return -ENODEV;
41
42 /* chip gets initialized by firmware */
43 data = i2c_smbus_read_byte_data(max->i2c, MAX6690_EXTERNAL_TEMP);
44 if (data < 0)
45 return data;
46 *value = data << 16;
47 return 0;
48}
49
50static void wf_max6690_release(struct wf_sensor *sr)
51{
52 struct wf_6690_sensor *max = wf_to_6690(sr);
53
54 kfree(max);
55}
56
57static const struct wf_sensor_ops wf_max6690_ops = {
58 .get_value = wf_max6690_get,
59 .release = wf_max6690_release,
60 .owner = THIS_MODULE,
61};
62
63static int wf_max6690_probe(struct i2c_client *client)
64{
65 const char *name, *loc;
66 struct wf_6690_sensor *max;
67 int rc;
68
69 loc = of_get_property(client->dev.of_node, "hwsensor-location", NULL);
70 if (!loc) {
71 dev_warn(&client->dev, "Missing hwsensor-location property!\n");
72 return -ENXIO;
73 }
74
75 /*
76 * We only expose the external temperature register for
77 * now as this is all we need for our control loops
78 */
79 if (!strcmp(loc, "BACKSIDE") || !strcmp(loc, "SYS CTRLR AMBIENT"))
80 name = "backside-temp";
81 else if (!strcmp(loc, "NB Ambient"))
82 name = "north-bridge-temp";
83 else if (!strcmp(loc, "GPU Ambient"))
84 name = "gpu-temp";
85 else
86 return -ENXIO;
87
88 max = kzalloc(sizeof(struct wf_6690_sensor), GFP_KERNEL);
89 if (max == NULL) {
90 printk(KERN_ERR "windfarm: Couldn't create MAX6690 sensor: "
91 "no memory\n");
92 return -ENOMEM;
93 }
94
95 max->i2c = client;
96 max->sens.name = name;
97 max->sens.ops = &wf_max6690_ops;
98 i2c_set_clientdata(client, max);
99
100 rc = wf_register_sensor(&max->sens);
101 if (rc)
102 kfree(max);
103 return rc;
104}
105
106static void wf_max6690_remove(struct i2c_client *client)
107{
108 struct wf_6690_sensor *max = i2c_get_clientdata(client);
109
110 max->i2c = NULL;
111 wf_unregister_sensor(&max->sens);
112}
113
114static const struct i2c_device_id wf_max6690_id[] = {
115 { "MAC,max6690" },
116 { }
117};
118MODULE_DEVICE_TABLE(i2c, wf_max6690_id);
119
120static const struct of_device_id wf_max6690_of_id[] = {
121 { .compatible = "max6690", },
122 { }
123};
124MODULE_DEVICE_TABLE(of, wf_max6690_of_id);
125
126static struct i2c_driver wf_max6690_driver = {
127 .driver = {
128 .name = "wf_max6690",
129 .of_match_table = wf_max6690_of_id,
130 },
131 .probe = wf_max6690_probe,
132 .remove = wf_max6690_remove,
133 .id_table = wf_max6690_id,
134};
135
136module_i2c_driver(wf_max6690_driver);
137
138MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
139MODULE_DESCRIPTION("MAX6690 sensor objects for PowerMac thermal control");
140MODULE_LICENSE("GPL");