[PATCH] e1000: Added hardware support for PCI express, 82546GB, and 82571 Fiber
[linux-2.6] / drivers / macintosh / windfarm_lm75_sensor.c
1 /*
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>
18 #include <linux/i2c-dev.h>
19 #include <asm/prom.h>
20 #include <asm/machdep.h>
21 #include <asm/io.h>
22 #include <asm/system.h>
23 #include <asm/sections.h>
24 #include <asm/pmac_low_i2c.h>
25
26 #include "windfarm.h"
27
28 #define VERSION "0.1"
29
30 #undef DEBUG
31
32 #ifdef DEBUG
33 #define DBG(args...)    printk(args)
34 #else
35 #define DBG(args...)    do { } while(0)
36 #endif
37
38 struct wf_lm75_sensor {
39         int                     ds1775 : 1;
40         int                     inited : 1;
41         struct  i2c_client      i2c;
42         struct  wf_sensor       sens;
43 };
44 #define wf_to_lm75(c) container_of(c, struct wf_lm75_sensor, sens)
45 #define i2c_to_lm75(c) container_of(c, struct wf_lm75_sensor, i2c)
46
47 static int wf_lm75_attach(struct i2c_adapter *adapter);
48 static int wf_lm75_detach(struct i2c_client *client);
49
50 static struct i2c_driver wf_lm75_driver = {
51         .driver = {
52                 .name   = "wf_lm75",
53         },
54         .attach_adapter = wf_lm75_attach,
55         .detach_client  = wf_lm75_detach,
56 };
57
58 static int wf_lm75_get(struct wf_sensor *sr, s32 *value)
59 {
60         struct wf_lm75_sensor *lm = wf_to_lm75(sr);
61         s32 data;
62
63         if (lm->i2c.adapter == NULL)
64                 return -ENODEV;
65
66         /* Init chip if necessary */
67         if (!lm->inited) {
68                 u8 cfg_new, cfg = (u8)i2c_smbus_read_byte_data(&lm->i2c, 1);
69
70                 DBG("wf_lm75: Initializing %s, cfg was: %02x\n",
71                     sr->name, cfg);
72
73                 /* clear shutdown bit, keep other settings as left by
74                  * the firmware for now
75                  */
76                 cfg_new = cfg & ~0x01;
77                 i2c_smbus_write_byte_data(&lm->i2c, 1, cfg_new);
78                 lm->inited = 1;
79
80                 /* If we just powered it up, let's wait 200 ms */
81                 msleep(200);
82         }
83
84         /* Read temperature register */
85         data = (s32)le16_to_cpu(i2c_smbus_read_word_data(&lm->i2c, 0));
86         data <<= 8;
87         *value = data;
88
89         return 0;
90 }
91
92 static void wf_lm75_release(struct wf_sensor *sr)
93 {
94         struct wf_lm75_sensor *lm = wf_to_lm75(sr);
95
96         /* check if client is registered and detach from i2c */
97         if (lm->i2c.adapter) {
98                 i2c_detach_client(&lm->i2c);
99                 lm->i2c.adapter = NULL;
100         }
101
102         kfree(lm);
103 }
104
105 static struct wf_sensor_ops wf_lm75_ops = {
106         .get_value      = wf_lm75_get,
107         .release        = wf_lm75_release,
108         .owner          = THIS_MODULE,
109 };
110
111 static struct wf_lm75_sensor *wf_lm75_create(struct i2c_adapter *adapter,
112                                              u8 addr, int ds1775,
113                                              const char *loc)
114 {
115         struct wf_lm75_sensor *lm;
116
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
142         if (i2c_attach_client(&lm->i2c)) {
143                 printk(KERN_ERR "windfarm: failed to attach %s %s to i2c\n",
144                        ds1775 ? "ds1775" : "lm75", lm->i2c.name);
145                 goto fail;
146         }
147
148         if (wf_register_sensor(&lm->sens)) {
149                 i2c_detach_client(&lm->i2c);
150                 goto fail;
151         }
152
153         return lm;
154  fail:
155         kfree(lm);
156         return NULL;
157 }
158
159 static int wf_lm75_attach(struct i2c_adapter *adapter)
160 {
161         struct device_node *busnode, *dev;
162         struct pmac_i2c_bus *bus;
163
164         DBG("wf_lm75: adapter %s detected\n", adapter->name);
165
166         bus = pmac_i2c_adapter_to_bus(adapter);
167         if (bus == NULL)
168                 return -ENODEV;
169         busnode = pmac_i2c_get_bus_node(bus);
170
171         DBG("wf_lm75: bus found, looking for device...\n");
172
173         /* Now look for lm75(s) in there */
174         for (dev = NULL;
175              (dev = of_get_next_child(busnode, dev)) != NULL;) {
176                 const char *loc =
177                         get_property(dev, "hwsensor-location", NULL);
178                 u32 *reg = (u32 *)get_property(dev, "reg", NULL);
179                 DBG(" dev: %s... (loc: %p, reg: %p)\n", dev->name, loc, reg);
180                 if (loc == NULL || reg == NULL)
181                         continue;
182                 /* real lm75 */
183                 if (device_is_compatible(dev, "lm75"))
184                         wf_lm75_create(adapter, *reg, 0, loc);
185                 /* ds1775 (compatible, better resolution */
186                 else if (device_is_compatible(dev, "ds1775"))
187                         wf_lm75_create(adapter, *reg, 1, loc);
188         }
189         return 0;
190 }
191
192 static int wf_lm75_detach(struct i2c_client *client)
193 {
194         struct wf_lm75_sensor *lm = i2c_to_lm75(client);
195
196         DBG("wf_lm75: i2c detatch called for %s\n", lm->sens.name);
197
198         /* Mark client detached */
199         lm->i2c.adapter = NULL;
200
201         /* release sensor */
202         wf_unregister_sensor(&lm->sens);
203
204         return 0;
205 }
206
207 static int __init wf_lm75_sensor_init(void)
208 {
209         return i2c_add_driver(&wf_lm75_driver);
210 }
211
212 static void __exit wf_lm75_sensor_exit(void)
213 {
214         i2c_del_driver(&wf_lm75_driver);
215 }
216
217
218 module_init(wf_lm75_sensor_init);
219 module_exit(wf_lm75_sensor_exit);
220
221 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
222 MODULE_DESCRIPTION("LM75 sensor objects for PowerMacs thermal control");
223 MODULE_LICENSE("GPL");
224