2 * Windfarm PowerMac thermal control. LM75 sensor
4 * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
5 * <benh@kernel.crashing.org>
7 * Released under the term of the GNU GPL v2.
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 <linux/of_device.h>
20 #include <asm/machdep.h>
22 #include <asm/sections.h>
23 #include <asm/pmac_low_i2c.h>
32 #define DBG(args...) printk(args)
34 #define DBG(args...) do { } while(0)
37 struct wf_lm75_sensor {
40 struct i2c_client *i2c;
41 struct wf_sensor sens;
43 #define wf_to_lm75(c) container_of(c, struct wf_lm75_sensor, sens)
45 static int wf_lm75_get(struct wf_sensor *sr, s32 *value)
47 struct wf_lm75_sensor *lm = wf_to_lm75(sr);
53 /* Init chip if necessary */
55 u8 cfg_new, cfg = (u8)i2c_smbus_read_byte_data(lm->i2c, 1);
57 DBG("wf_lm75: Initializing %s, cfg was: %02x\n",
60 /* clear shutdown bit, keep other settings as left by
61 * the firmware for now
63 cfg_new = cfg & ~0x01;
64 i2c_smbus_write_byte_data(lm->i2c, 1, cfg_new);
67 /* If we just powered it up, let's wait 200 ms */
71 /* Read temperature register */
72 data = (s32)le16_to_cpu(i2c_smbus_read_word_data(lm->i2c, 0));
79 static void wf_lm75_release(struct wf_sensor *sr)
81 struct wf_lm75_sensor *lm = wf_to_lm75(sr);
86 static const struct wf_sensor_ops wf_lm75_ops = {
87 .get_value = wf_lm75_get,
88 .release = wf_lm75_release,
92 static int wf_lm75_probe(struct i2c_client *client,
93 const struct i2c_device_id *id)
95 struct wf_lm75_sensor *lm;
97 const char *name, *loc;
100 ds1775 = id->driver_data;
102 ds1775 = !!of_device_get_match_data(&client->dev);
104 DBG("wf_lm75: creating %s device at address 0x%02x\n",
105 ds1775 ? "ds1775" : "lm75", client->addr);
107 loc = of_get_property(client->dev.of_node, "hwsensor-location", NULL);
109 dev_warn(&client->dev, "Missing hwsensor-location property!\n");
113 /* Usual rant about sensor names not beeing very consistent in
114 * the device-tree, oh well ...
115 * Add more entries below as you deal with more setups
117 if (!strcmp(loc, "Hard drive") || !strcmp(loc, "DRIVE BAY"))
119 else if (!strcmp(loc, "Incoming Air Temp"))
120 name = "incoming-air-temp";
121 else if (!strcmp(loc, "ODD Temp"))
122 name = "optical-drive-temp";
123 else if (!strcmp(loc, "HD Temp"))
124 name = "hard-drive-temp";
125 else if (!strcmp(loc, "PCI SLOTS"))
127 else if (!strcmp(loc, "CPU A INLET"))
128 name = "cpu-inlet-temp-0";
129 else if (!strcmp(loc, "CPU B INLET"))
130 name = "cpu-inlet-temp-1";
135 lm = kzalloc(sizeof(struct wf_lm75_sensor), GFP_KERNEL);
142 lm->sens.name = name;
143 lm->sens.ops = &wf_lm75_ops;
144 i2c_set_clientdata(client, lm);
146 rc = wf_register_sensor(&lm->sens);
152 static int wf_lm75_remove(struct i2c_client *client)
154 struct wf_lm75_sensor *lm = i2c_get_clientdata(client);
156 DBG("wf_lm75: i2c detatch called for %s\n", lm->sens.name);
158 /* Mark client detached */
162 wf_unregister_sensor(&lm->sens);
167 static const struct i2c_device_id wf_lm75_id[] = {
172 MODULE_DEVICE_TABLE(i2c, wf_lm75_id);
174 static const struct of_device_id wf_lm75_of_id[] = {
175 { .compatible = "lm75", .data = (void *)0},
176 { .compatible = "ds1775", .data = (void *)1 },
179 MODULE_DEVICE_TABLE(of, wf_lm75_of_id);
181 static struct i2c_driver wf_lm75_driver = {
184 .of_match_table = wf_lm75_of_id,
186 .probe = wf_lm75_probe,
187 .remove = wf_lm75_remove,
188 .id_table = wf_lm75_id,
191 module_i2c_driver(wf_lm75_driver);
193 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
194 MODULE_DESCRIPTION("LM75 sensor objects for PowerMacs thermal control");
195 MODULE_LICENSE("GPL");