ia64/linux-2.6.18-xen.hg

view drivers/macintosh/windfarm_lm75_sensor.c @ 893:f994bfe9b93b

linux/blktap2: reduce TLB flush scope

c/s 885 added very coarse TLB flushing. Since these flushes always
follow single page updates, single page flushes (when available) are
sufficient.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Jun 04 10:32:57 2009 +0100 (2009-06-04)
parents 831230e53067
children
line source
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 */
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 <asm/prom.h>
19 #include <asm/machdep.h>
20 #include <asm/io.h>
21 #include <asm/system.h>
22 #include <asm/sections.h>
23 #include <asm/pmac_low_i2c.h>
25 #include "windfarm.h"
27 #define VERSION "0.2"
29 #undef DEBUG
31 #ifdef DEBUG
32 #define DBG(args...) printk(args)
33 #else
34 #define DBG(args...) do { } while(0)
35 #endif
37 struct 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)
46 static int wf_lm75_attach(struct i2c_adapter *adapter);
47 static int wf_lm75_detach(struct i2c_client *client);
49 static struct i2c_driver wf_lm75_driver = {
50 .driver = {
51 .name = "wf_lm75",
52 },
53 .attach_adapter = wf_lm75_attach,
54 .detach_client = wf_lm75_detach,
55 };
57 static int wf_lm75_get(struct wf_sensor *sr, s32 *value)
58 {
59 struct wf_lm75_sensor *lm = wf_to_lm75(sr);
60 s32 data;
62 if (lm->i2c.adapter == NULL)
63 return -ENODEV;
65 /* Init chip if necessary */
66 if (!lm->inited) {
67 u8 cfg_new, cfg = (u8)i2c_smbus_read_byte_data(&lm->i2c, 1);
69 DBG("wf_lm75: Initializing %s, cfg was: %02x\n",
70 sr->name, cfg);
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;
79 /* If we just powered it up, let's wait 200 ms */
80 msleep(200);
81 }
83 /* Read temperature register */
84 data = (s32)le16_to_cpu(i2c_smbus_read_word_data(&lm->i2c, 0));
85 data <<= 8;
86 *value = data;
88 return 0;
89 }
91 static void wf_lm75_release(struct wf_sensor *sr)
92 {
93 struct wf_lm75_sensor *lm = wf_to_lm75(sr);
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 }
101 kfree(lm);
102 }
104 static struct wf_sensor_ops wf_lm75_ops = {
105 .get_value = wf_lm75_get,
106 .release = wf_lm75_release,
107 .owner = THIS_MODULE,
108 };
110 static 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;
115 int rc;
117 DBG("wf_lm75: creating %s device at address 0x%02x\n",
118 ds1775 ? "ds1775" : "lm75", addr);
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));
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;
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);
142 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);
147 goto fail;
148 }
150 if (wf_register_sensor(&lm->sens)) {
151 i2c_detach_client(&lm->i2c);
152 goto fail;
153 }
155 return lm;
156 fail:
157 kfree(lm);
158 return NULL;
159 }
161 static int wf_lm75_attach(struct i2c_adapter *adapter)
162 {
163 struct device_node *busnode, *dev;
164 struct pmac_i2c_bus *bus;
166 DBG("wf_lm75: adapter %s detected\n", adapter->name);
168 bus = pmac_i2c_adapter_to_bus(adapter);
169 if (bus == NULL)
170 return -ENODEV;
171 busnode = pmac_i2c_get_bus_node(bus);
173 DBG("wf_lm75: bus found, looking for device...\n");
175 /* Now look for lm75(s) in there */
176 for (dev = NULL;
177 (dev = of_get_next_child(busnode, dev)) != NULL;) {
178 const char *loc =
179 get_property(dev, "hwsensor-location", NULL);
180 u8 addr;
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)
189 continue;
190 /* real lm75 */
191 if (device_is_compatible(dev, "lm75"))
192 wf_lm75_create(adapter, addr, 0, loc);
193 /* ds1775 (compatible, better resolution */
194 else if (device_is_compatible(dev, "ds1775"))
195 wf_lm75_create(adapter, addr, 1, loc);
196 }
197 return 0;
198 }
200 static int wf_lm75_detach(struct i2c_client *client)
201 {
202 struct wf_lm75_sensor *lm = i2c_to_lm75(client);
204 DBG("wf_lm75: i2c detatch called for %s\n", lm->sens.name);
206 /* Mark client detached */
207 lm->i2c.adapter = NULL;
209 /* release sensor */
210 wf_unregister_sensor(&lm->sens);
212 return 0;
213 }
215 static int __init wf_lm75_sensor_init(void)
216 {
217 /* 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;
222 return i2c_add_driver(&wf_lm75_driver);
223 }
225 static void __exit wf_lm75_sensor_exit(void)
226 {
227 i2c_del_driver(&wf_lm75_driver);
228 }
231 module_init(wf_lm75_sensor_init);
232 module_exit(wf_lm75_sensor_exit);
234 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
235 MODULE_DESCRIPTION("LM75 sensor objects for PowerMacs thermal control");
236 MODULE_LICENSE("GPL");