Commit | Line | Data |
---|---|---|
ac171c46 BH |
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 <linux/i2c-dev.h> | |
15 | #include <asm/prom.h> | |
16 | #include <asm/pmac_low_i2c.h> | |
17 | ||
18 | #include "windfarm.h" | |
19 | ||
20 | #define VERSION "0.1" | |
21 | ||
22 | /* This currently only exports the external temperature sensor, | |
23 | since that's all the control loops need. */ | |
24 | ||
25 | /* Some MAX6690 register numbers */ | |
26 | #define MAX6690_INTERNAL_TEMP 0 | |
27 | #define MAX6690_EXTERNAL_TEMP 1 | |
28 | ||
29 | struct wf_6690_sensor { | |
30 | struct i2c_client i2c; | |
31 | struct wf_sensor sens; | |
32 | }; | |
33 | ||
34 | #define wf_to_6690(x) container_of((x), struct wf_6690_sensor, sens) | |
35 | #define i2c_to_6690(x) container_of((x), struct wf_6690_sensor, i2c) | |
36 | ||
37 | static int wf_max6690_attach(struct i2c_adapter *adapter); | |
38 | static int wf_max6690_detach(struct i2c_client *client); | |
39 | ||
40 | static struct i2c_driver wf_max6690_driver = { | |
41 | .driver = { | |
42 | .name = "wf_max6690", | |
43 | }, | |
44 | .attach_adapter = wf_max6690_attach, | |
45 | .detach_client = wf_max6690_detach, | |
46 | }; | |
47 | ||
48 | static int wf_max6690_get(struct wf_sensor *sr, s32 *value) | |
49 | { | |
50 | struct wf_6690_sensor *max = wf_to_6690(sr); | |
51 | s32 data; | |
52 | ||
53 | if (max->i2c.adapter == NULL) | |
54 | return -ENODEV; | |
55 | ||
56 | /* chip gets initialized by firmware */ | |
57 | data = i2c_smbus_read_byte_data(&max->i2c, MAX6690_EXTERNAL_TEMP); | |
58 | if (data < 0) | |
59 | return data; | |
60 | *value = data << 16; | |
61 | return 0; | |
62 | } | |
63 | ||
64 | static void wf_max6690_release(struct wf_sensor *sr) | |
65 | { | |
66 | struct wf_6690_sensor *max = wf_to_6690(sr); | |
67 | ||
68 | if (max->i2c.adapter) { | |
69 | i2c_detach_client(&max->i2c); | |
70 | max->i2c.adapter = NULL; | |
71 | } | |
72 | kfree(max); | |
73 | } | |
74 | ||
75 | static struct wf_sensor_ops wf_max6690_ops = { | |
76 | .get_value = wf_max6690_get, | |
77 | .release = wf_max6690_release, | |
78 | .owner = THIS_MODULE, | |
79 | }; | |
80 | ||
81 | static void wf_max6690_create(struct i2c_adapter *adapter, u8 addr) | |
82 | { | |
83 | struct wf_6690_sensor *max; | |
84 | char *name = "u4-temp"; | |
85 | ||
86 | max = kzalloc(sizeof(struct wf_6690_sensor), GFP_KERNEL); | |
87 | if (max == NULL) { | |
88 | printk(KERN_ERR "windfarm: Couldn't create MAX6690 sensor %s: " | |
89 | "no memory\n", name); | |
90 | return; | |
91 | } | |
92 | ||
93 | max->sens.ops = &wf_max6690_ops; | |
94 | max->sens.name = name; | |
95 | max->i2c.addr = addr >> 1; | |
96 | max->i2c.adapter = adapter; | |
97 | max->i2c.driver = &wf_max6690_driver; | |
98 | strncpy(max->i2c.name, name, I2C_NAME_SIZE-1); | |
99 | ||
100 | if (i2c_attach_client(&max->i2c)) { | |
101 | printk(KERN_ERR "windfarm: failed to attach MAX6690 sensor\n"); | |
102 | goto fail; | |
103 | } | |
104 | ||
105 | if (wf_register_sensor(&max->sens)) { | |
106 | i2c_detach_client(&max->i2c); | |
107 | goto fail; | |
108 | } | |
109 | ||
110 | return; | |
111 | ||
112 | fail: | |
113 | kfree(max); | |
114 | } | |
115 | ||
116 | static int wf_max6690_attach(struct i2c_adapter *adapter) | |
117 | { | |
118 | struct device_node *busnode, *dev = NULL; | |
119 | struct pmac_i2c_bus *bus; | |
120 | const char *loc; | |
121 | u32 *reg; | |
122 | ||
123 | bus = pmac_i2c_adapter_to_bus(adapter); | |
124 | if (bus == NULL) | |
125 | return -ENODEV; | |
126 | busnode = pmac_i2c_get_bus_node(bus); | |
127 | ||
128 | while ((dev = of_get_next_child(busnode, dev)) != NULL) { | |
129 | if (!device_is_compatible(dev, "max6690")) | |
130 | continue; | |
131 | loc = get_property(dev, "hwsensor-location", NULL); | |
132 | reg = (u32 *) get_property(dev, "reg", NULL); | |
133 | if (!loc || !reg) | |
134 | continue; | |
135 | printk("found max6690, loc=%s reg=%x\n", loc, *reg); | |
136 | if (strcmp(loc, "BACKSIDE")) | |
137 | continue; | |
138 | wf_max6690_create(adapter, *reg); | |
139 | } | |
140 | ||
141 | return 0; | |
142 | } | |
143 | ||
144 | static int wf_max6690_detach(struct i2c_client *client) | |
145 | { | |
146 | struct wf_6690_sensor *max = i2c_to_6690(client); | |
147 | ||
148 | max->i2c.adapter = NULL; | |
149 | wf_unregister_sensor(&max->sens); | |
150 | ||
151 | return 0; | |
152 | } | |
153 | ||
154 | static int __init wf_max6690_sensor_init(void) | |
155 | { | |
156 | return i2c_add_driver(&wf_max6690_driver); | |
157 | } | |
158 | ||
159 | static void __exit wf_max6690_sensor_exit(void) | |
160 | { | |
161 | i2c_del_driver(&wf_max6690_driver); | |
162 | } | |
163 | ||
164 | module_init(wf_max6690_sensor_init); | |
165 | module_exit(wf_max6690_sensor_exit); | |
166 | ||
167 | MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>"); | |
168 | MODULE_DESCRIPTION("MAX6690 sensor objects for PowerMac thermal control"); | |
169 | MODULE_LICENSE("GPL"); |