blob: 3f7967feaf5b7e7900c3134e40cb5b3f33fef493 [file] [log] [blame]
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +11001/*
2 * Windfarm PowerMac thermal control. LM75 sensor
3 *
4 * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
5 * <benh@kernel.crashing.org>
6 *
7 * Released under the term of the GNU GPL v2.
8 */
9
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>
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +110018#include <asm/prom.h>
19#include <asm/machdep.h>
20#include <asm/io.h>
21#include <asm/system.h>
22#include <asm/sections.h>
Benjamin Herrenschmidta28d3af2006-01-07 11:35:26 +110023#include <asm/pmac_low_i2c.h>
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +110024
25#include "windfarm.h"
26
Benjamin Herrenschmidtb55fafc2006-03-03 17:03:21 +110027#define VERSION "0.2"
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +110028
29#undef DEBUG
30
31#ifdef DEBUG
32#define DBG(args...) printk(args)
33#else
34#define DBG(args...) do { } while(0)
35#endif
36
37struct wf_lm75_sensor {
38 int ds1775 : 1;
39 int inited : 1;
40 struct i2c_client i2c;
41 struct wf_sensor sens;
42};
43#define wf_to_lm75(c) container_of(c, struct wf_lm75_sensor, sens)
44#define i2c_to_lm75(c) container_of(c, struct wf_lm75_sensor, i2c)
45
46static int wf_lm75_attach(struct i2c_adapter *adapter);
47static int wf_lm75_detach(struct i2c_client *client);
48
49static struct i2c_driver wf_lm75_driver = {
Laurent Riffarda33ca232005-11-26 20:40:34 +010050 .driver = {
Laurent Riffarda33ca232005-11-26 20:40:34 +010051 .name = "wf_lm75",
52 },
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +110053 .attach_adapter = wf_lm75_attach,
54 .detach_client = wf_lm75_detach,
55};
56
57static int wf_lm75_get(struct wf_sensor *sr, s32 *value)
58{
59 struct wf_lm75_sensor *lm = wf_to_lm75(sr);
60 s32 data;
61
62 if (lm->i2c.adapter == NULL)
63 return -ENODEV;
64
65 /* Init chip if necessary */
66 if (!lm->inited) {
67 u8 cfg_new, cfg = (u8)i2c_smbus_read_byte_data(&lm->i2c, 1);
68
69 DBG("wf_lm75: Initializing %s, cfg was: %02x\n",
70 sr->name, cfg);
71
72 /* clear shutdown bit, keep other settings as left by
73 * the firmware for now
74 */
75 cfg_new = cfg & ~0x01;
76 i2c_smbus_write_byte_data(&lm->i2c, 1, cfg_new);
77 lm->inited = 1;
78
79 /* If we just powered it up, let's wait 200 ms */
80 msleep(200);
81 }
82
83 /* Read temperature register */
84 data = (s32)le16_to_cpu(i2c_smbus_read_word_data(&lm->i2c, 0));
85 data <<= 8;
86 *value = data;
87
88 return 0;
89}
90
91static void wf_lm75_release(struct wf_sensor *sr)
92{
93 struct wf_lm75_sensor *lm = wf_to_lm75(sr);
94
95 /* check if client is registered and detach from i2c */
96 if (lm->i2c.adapter) {
97 i2c_detach_client(&lm->i2c);
98 lm->i2c.adapter = NULL;
99 }
100
101 kfree(lm);
102}
103
104static struct wf_sensor_ops wf_lm75_ops = {
105 .get_value = wf_lm75_get,
106 .release = wf_lm75_release,
107 .owner = THIS_MODULE,
108};
109
110static struct wf_lm75_sensor *wf_lm75_create(struct i2c_adapter *adapter,
111 u8 addr, int ds1775,
112 const char *loc)
113{
114 struct wf_lm75_sensor *lm;
Benjamin Herrenschmidtb55fafc2006-03-03 17:03:21 +1100115 int rc;
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +1100116
117 DBG("wf_lm75: creating %s device at address 0x%02x\n",
118 ds1775 ? "ds1775" : "lm75", addr);
119
120 lm = kmalloc(sizeof(struct wf_lm75_sensor), GFP_KERNEL);
121 if (lm == NULL)
122 return NULL;
123 memset(lm, 0, sizeof(struct wf_lm75_sensor));
124
125 /* Usual rant about sensor names not beeing very consistent in
126 * the device-tree, oh well ...
127 * Add more entries below as you deal with more setups
128 */
129 if (!strcmp(loc, "Hard drive") || !strcmp(loc, "DRIVE BAY"))
130 lm->sens.name = "hd-temp";
131 else
132 goto fail;
133
134 lm->inited = 0;
135 lm->sens.ops = &wf_lm75_ops;
136 lm->ds1775 = ds1775;
137 lm->i2c.addr = (addr >> 1) & 0x7f;
138 lm->i2c.adapter = adapter;
139 lm->i2c.driver = &wf_lm75_driver;
140 strncpy(lm->i2c.name, lm->sens.name, I2C_NAME_SIZE-1);
141
Benjamin Herrenschmidtb55fafc2006-03-03 17:03:21 +1100142 rc = i2c_attach_client(&lm->i2c);
143 if (rc) {
144 printk(KERN_ERR "windfarm: failed to attach %s %s to i2c,"
145 " err %d\n", ds1775 ? "ds1775" : "lm75",
146 lm->i2c.name, rc);
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +1100147 goto fail;
148 }
149
150 if (wf_register_sensor(&lm->sens)) {
151 i2c_detach_client(&lm->i2c);
152 goto fail;
153 }
154
155 return lm;
156 fail:
157 kfree(lm);
158 return NULL;
159}
160
161static int wf_lm75_attach(struct i2c_adapter *adapter)
162{
Benjamin Herrenschmidta28d3af2006-01-07 11:35:26 +1100163 struct device_node *busnode, *dev;
164 struct pmac_i2c_bus *bus;
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +1100165
166 DBG("wf_lm75: adapter %s detected\n", adapter->name);
167
Benjamin Herrenschmidta28d3af2006-01-07 11:35:26 +1100168 bus = pmac_i2c_adapter_to_bus(adapter);
169 if (bus == NULL)
170 return -ENODEV;
171 busnode = pmac_i2c_get_bus_node(bus);
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +1100172
173 DBG("wf_lm75: bus found, looking for device...\n");
174
175 /* Now look for lm75(s) in there */
176 for (dev = NULL;
Benjamin Herrenschmidta28d3af2006-01-07 11:35:26 +1100177 (dev = of_get_next_child(busnode, dev)) != NULL;) {
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +1100178 const char *loc =
179 get_property(dev, "hwsensor-location", NULL);
Benjamin Herrenschmidtb55fafc2006-03-03 17:03:21 +1100180 u8 addr;
181
182 /* We must re-match the adapter in order to properly check
183 * the channel on multibus setups
184 */
185 if (!pmac_i2c_match_adapter(dev, adapter))
186 continue;
187 addr = pmac_i2c_get_dev_addr(dev);
188 if (loc == NULL || addr == 0)
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +1100189 continue;
190 /* real lm75 */
191 if (device_is_compatible(dev, "lm75"))
Benjamin Herrenschmidtb55fafc2006-03-03 17:03:21 +1100192 wf_lm75_create(adapter, addr, 0, loc);
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +1100193 /* ds1775 (compatible, better resolution */
194 else if (device_is_compatible(dev, "ds1775"))
Benjamin Herrenschmidtb55fafc2006-03-03 17:03:21 +1100195 wf_lm75_create(adapter, addr, 1, loc);
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +1100196 }
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +1100197 return 0;
198}
199
200static int wf_lm75_detach(struct i2c_client *client)
201{
202 struct wf_lm75_sensor *lm = i2c_to_lm75(client);
203
204 DBG("wf_lm75: i2c detatch called for %s\n", lm->sens.name);
205
206 /* Mark client detached */
207 lm->i2c.adapter = NULL;
208
209 /* release sensor */
210 wf_unregister_sensor(&lm->sens);
211
212 return 0;
213}
214
215static int __init wf_lm75_sensor_init(void)
216{
Benjamin Herrenschmidtb55fafc2006-03-03 17:03:21 +1100217 /* Don't register on old machines that use therm_pm72 for now */
218 if (machine_is_compatible("PowerMac7,2") ||
219 machine_is_compatible("PowerMac7,3") ||
220 machine_is_compatible("RackMac3,1"))
221 return -ENODEV;
Arthur Othienoc9662b42006-01-06 00:11:29 -0800222 return i2c_add_driver(&wf_lm75_driver);
Benjamin Herrenschmidt75722d32005-11-07 16:08:17 +1100223}
224
225static void __exit wf_lm75_sensor_exit(void)
226{
227 i2c_del_driver(&wf_lm75_driver);
228}
229
230
231module_init(wf_lm75_sensor_init);
232module_exit(wf_lm75_sensor_exit);
233
234MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
235MODULE_DESCRIPTION("LM75 sensor objects for PowerMacs thermal control");
236MODULE_LICENSE("GPL");
237