[PATCH] Document online io scheduler switching
[linux-2.6] / drivers / hwmon / gl518sm.c
1 /*
2  * gl518sm.c - Part of lm_sensors, Linux kernel modules for hardware
3  *             monitoring
4  * Copyright (C) 1998, 1999 Frodo Looijaard <frodol@dds.nl> and
5  * Kyosti Malkki <kmalkki@cc.hut.fi>
6  * Copyright (C) 2004 Hong-Gunn Chew <hglinux@gunnet.org> and
7  * Jean Delvare <khali@linux-fr.org>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  *
23  * Ported to Linux 2.6 by Hong-Gunn Chew with the help of Jean Delvare
24  * and advice of Greg Kroah-Hartman.
25  *
26  * Notes about the port:
27  * Release 0x00 of the GL518SM chipset doesn't support reading of in0,
28  * in1 nor in2. The original driver had an ugly workaround to get them
29  * anyway (changing limits and watching alarms trigger and wear off).
30  * We did not keep that part of the original driver in the Linux 2.6
31  * version, since it was making the driver significantly more complex
32  * with no real benefit.
33  *
34  * History:
35  * 2004-01-28  Original port. (Hong-Gunn Chew)
36  * 2004-01-31  Code review and approval. (Jean Delvare)
37  */
38
39 #include <linux/module.h>
40 #include <linux/init.h>
41 #include <linux/slab.h>
42 #include <linux/jiffies.h>
43 #include <linux/i2c.h>
44 #include <linux/hwmon.h>
45 #include <linux/err.h>
46 #include <linux/mutex.h>
47
48 /* Addresses to scan */
49 static unsigned short normal_i2c[] = { 0x2c, 0x2d, I2C_CLIENT_END };
50
51 /* Insmod parameters */
52 I2C_CLIENT_INSMOD_2(gl518sm_r00, gl518sm_r80);
53
54 /* Many GL518 constants specified below */
55
56 /* The GL518 registers */
57 #define GL518_REG_CHIP_ID       0x00
58 #define GL518_REG_REVISION      0x01
59 #define GL518_REG_VENDOR_ID     0x02
60 #define GL518_REG_CONF          0x03
61 #define GL518_REG_TEMP_IN       0x04
62 #define GL518_REG_TEMP_MAX      0x05
63 #define GL518_REG_TEMP_HYST     0x06
64 #define GL518_REG_FAN_COUNT     0x07
65 #define GL518_REG_FAN_LIMIT     0x08
66 #define GL518_REG_VIN1_LIMIT    0x09
67 #define GL518_REG_VIN2_LIMIT    0x0a
68 #define GL518_REG_VIN3_LIMIT    0x0b
69 #define GL518_REG_VDD_LIMIT     0x0c
70 #define GL518_REG_VIN3          0x0d
71 #define GL518_REG_MISC          0x0f
72 #define GL518_REG_ALARM         0x10
73 #define GL518_REG_MASK          0x11
74 #define GL518_REG_INT           0x12
75 #define GL518_REG_VIN2          0x13
76 #define GL518_REG_VIN1          0x14
77 #define GL518_REG_VDD           0x15
78
79
80 /*
81  * Conversions. Rounding and limit checking is only done on the TO_REG
82  * variants. Note that you should be a bit careful with which arguments
83  * these macros are called: arguments may be evaluated more than once.
84  * Fixing this is just not worth it.
85  */
86
87 #define RAW_FROM_REG(val)       val
88
89 #define BOOL_FROM_REG(val)      ((val)?0:1)
90 #define BOOL_TO_REG(val)        ((val)?0:1)
91
92 #define TEMP_TO_REG(val)        (SENSORS_LIMIT(((((val)<0? \
93                                 (val)-500:(val)+500)/1000)+119),0,255))
94 #define TEMP_FROM_REG(val)      (((val) - 119) * 1000)
95
96 static inline u8 FAN_TO_REG(long rpm, int div)
97 {
98         long rpmdiv;
99         if (rpm == 0)
100                 return 0;
101         rpmdiv = SENSORS_LIMIT(rpm, 1, 1920000) * div;
102         return SENSORS_LIMIT((960000 + rpmdiv / 2) / rpmdiv, 1, 255);
103 }
104 #define FAN_FROM_REG(val,div)   ((val)==0 ? 0 : (960000/((val)*(div))))
105
106 #define IN_TO_REG(val)          (SENSORS_LIMIT((((val)+9)/19),0,255))
107 #define IN_FROM_REG(val)        ((val)*19)
108
109 #define VDD_TO_REG(val)         (SENSORS_LIMIT((((val)*4+47)/95),0,255))
110 #define VDD_FROM_REG(val)       (((val)*95+2)/4)
111
112 #define DIV_TO_REG(val)         ((val)==4?2:(val)==2?1:(val)==1?0:3)
113 #define DIV_FROM_REG(val)       (1 << (val))
114
115 #define BEEP_MASK_TO_REG(val)   ((val) & 0x7f & data->alarm_mask)
116 #define BEEP_MASK_FROM_REG(val) ((val) & 0x7f)
117
118 /* Each client has this additional data */
119 struct gl518_data {
120         struct i2c_client client;
121         struct class_device *class_dev;
122         enum chips type;
123
124         struct mutex update_lock;
125         char valid;             /* !=0 if following fields are valid */
126         unsigned long last_updated;     /* In jiffies */
127
128         u8 voltage_in[4];       /* Register values; [0] = VDD */
129         u8 voltage_min[4];      /* Register values; [0] = VDD */
130         u8 voltage_max[4];      /* Register values; [0] = VDD */
131         u8 iter_voltage_in[4];  /* Register values; [0] = VDD */
132         u8 fan_in[2];
133         u8 fan_min[2];
134         u8 fan_div[2];          /* Register encoding, shifted right */
135         u8 fan_auto1;           /* Boolean */
136         u8 temp_in;             /* Register values */
137         u8 temp_max;            /* Register values */
138         u8 temp_hyst;           /* Register values */
139         u8 alarms;              /* Register value */
140         u8 alarm_mask;          /* Register value */
141         u8 beep_mask;           /* Register value */
142         u8 beep_enable;         /* Boolean */
143 };
144
145 static int gl518_attach_adapter(struct i2c_adapter *adapter);
146 static int gl518_detect(struct i2c_adapter *adapter, int address, int kind);
147 static void gl518_init_client(struct i2c_client *client);
148 static int gl518_detach_client(struct i2c_client *client);
149 static int gl518_read_value(struct i2c_client *client, u8 reg);
150 static int gl518_write_value(struct i2c_client *client, u8 reg, u16 value);
151 static struct gl518_data *gl518_update_device(struct device *dev);
152
153 /* This is the driver that will be inserted */
154 static struct i2c_driver gl518_driver = {
155         .driver = {
156                 .name   = "gl518sm",
157         },
158         .id             = I2C_DRIVERID_GL518,
159         .attach_adapter = gl518_attach_adapter,
160         .detach_client  = gl518_detach_client,
161 };
162
163 /*
164  * Sysfs stuff
165  */
166
167 #define show(type, suffix, value)                                       \
168 static ssize_t show_##suffix(struct device *dev, struct device_attribute *attr, char *buf)              \
169 {                                                                       \
170         struct gl518_data *data = gl518_update_device(dev);             \
171         return sprintf(buf, "%d\n", type##_FROM_REG(data->value));      \
172 }
173
174 #define show_fan(suffix, value, index)                                  \
175 static ssize_t show_##suffix(struct device *dev, struct device_attribute *attr, char *buf)              \
176 {                                                                       \
177         struct gl518_data *data = gl518_update_device(dev);             \
178         return sprintf(buf, "%d\n", FAN_FROM_REG(data->value[index],    \
179                 DIV_FROM_REG(data->fan_div[index])));                   \
180 }
181
182 show(TEMP, temp_input1, temp_in);
183 show(TEMP, temp_max1, temp_max);
184 show(TEMP, temp_hyst1, temp_hyst);
185 show(BOOL, fan_auto1, fan_auto1);
186 show_fan(fan_input1, fan_in, 0);
187 show_fan(fan_input2, fan_in, 1);
188 show_fan(fan_min1, fan_min, 0);
189 show_fan(fan_min2, fan_min, 1);
190 show(DIV, fan_div1, fan_div[0]);
191 show(DIV, fan_div2, fan_div[1]);
192 show(VDD, in_input0, voltage_in[0]);
193 show(IN, in_input1, voltage_in[1]);
194 show(IN, in_input2, voltage_in[2]);
195 show(IN, in_input3, voltage_in[3]);
196 show(VDD, in_min0, voltage_min[0]);
197 show(IN, in_min1, voltage_min[1]);
198 show(IN, in_min2, voltage_min[2]);
199 show(IN, in_min3, voltage_min[3]);
200 show(VDD, in_max0, voltage_max[0]);
201 show(IN, in_max1, voltage_max[1]);
202 show(IN, in_max2, voltage_max[2]);
203 show(IN, in_max3, voltage_max[3]);
204 show(RAW, alarms, alarms);
205 show(BOOL, beep_enable, beep_enable);
206 show(BEEP_MASK, beep_mask, beep_mask);
207
208 #define set(type, suffix, value, reg)                                   \
209 static ssize_t set_##suffix(struct device *dev, struct device_attribute *attr, const char *buf, \
210         size_t count)                                                   \
211 {                                                                       \
212         struct i2c_client *client = to_i2c_client(dev);                 \
213         struct gl518_data *data = i2c_get_clientdata(client);           \
214         long val = simple_strtol(buf, NULL, 10);                        \
215                                                                         \
216         mutex_lock(&data->update_lock);                                 \
217         data->value = type##_TO_REG(val);                               \
218         gl518_write_value(client, reg, data->value);                    \
219         mutex_unlock(&data->update_lock);                               \
220         return count;                                                   \
221 }
222
223 #define set_bits(type, suffix, value, reg, mask, shift)                 \
224 static ssize_t set_##suffix(struct device *dev, struct device_attribute *attr, const char *buf, \
225         size_t count)                                                   \
226 {                                                                       \
227         struct i2c_client *client = to_i2c_client(dev);                 \
228         struct gl518_data *data = i2c_get_clientdata(client);           \
229         int regvalue;                                                   \
230         unsigned long val = simple_strtoul(buf, NULL, 10);              \
231                                                                         \
232         mutex_lock(&data->update_lock);                                 \
233         regvalue = gl518_read_value(client, reg);                       \
234         data->value = type##_TO_REG(val);                               \
235         regvalue = (regvalue & ~mask) | (data->value << shift);         \
236         gl518_write_value(client, reg, regvalue);                       \
237         mutex_unlock(&data->update_lock);                               \
238         return count;                                                   \
239 }
240
241 #define set_low(type, suffix, value, reg)                               \
242         set_bits(type, suffix, value, reg, 0x00ff, 0)
243 #define set_high(type, suffix, value, reg)                              \
244         set_bits(type, suffix, value, reg, 0xff00, 8)
245
246 set(TEMP, temp_max1, temp_max, GL518_REG_TEMP_MAX);
247 set(TEMP, temp_hyst1, temp_hyst, GL518_REG_TEMP_HYST);
248 set_bits(BOOL, fan_auto1, fan_auto1, GL518_REG_MISC, 0x08, 3);
249 set_bits(DIV, fan_div1, fan_div[0], GL518_REG_MISC, 0xc0, 6);
250 set_bits(DIV, fan_div2, fan_div[1], GL518_REG_MISC, 0x30, 4);
251 set_low(VDD, in_min0, voltage_min[0], GL518_REG_VDD_LIMIT);
252 set_low(IN, in_min1, voltage_min[1], GL518_REG_VIN1_LIMIT);
253 set_low(IN, in_min2, voltage_min[2], GL518_REG_VIN2_LIMIT);
254 set_low(IN, in_min3, voltage_min[3], GL518_REG_VIN3_LIMIT);
255 set_high(VDD, in_max0, voltage_max[0], GL518_REG_VDD_LIMIT);
256 set_high(IN, in_max1, voltage_max[1], GL518_REG_VIN1_LIMIT);
257 set_high(IN, in_max2, voltage_max[2], GL518_REG_VIN2_LIMIT);
258 set_high(IN, in_max3, voltage_max[3], GL518_REG_VIN3_LIMIT);
259 set_bits(BOOL, beep_enable, beep_enable, GL518_REG_CONF, 0x04, 2);
260 set(BEEP_MASK, beep_mask, beep_mask, GL518_REG_ALARM);
261
262 static ssize_t set_fan_min1(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
263 {
264         struct i2c_client *client = to_i2c_client(dev);
265         struct gl518_data *data = i2c_get_clientdata(client);
266         int regvalue;
267         unsigned long val = simple_strtoul(buf, NULL, 10);
268
269         mutex_lock(&data->update_lock);
270         regvalue = gl518_read_value(client, GL518_REG_FAN_LIMIT);
271         data->fan_min[0] = FAN_TO_REG(val,
272                 DIV_FROM_REG(data->fan_div[0]));
273         regvalue = (regvalue & 0x00ff) | (data->fan_min[0] << 8);
274         gl518_write_value(client, GL518_REG_FAN_LIMIT, regvalue);
275
276         data->beep_mask = gl518_read_value(client, GL518_REG_ALARM);
277         if (data->fan_min[0] == 0)
278                 data->alarm_mask &= ~0x20;
279         else
280                 data->alarm_mask |= 0x20;
281         data->beep_mask &= data->alarm_mask;
282         gl518_write_value(client, GL518_REG_ALARM, data->beep_mask);
283
284         mutex_unlock(&data->update_lock);
285         return count;
286 }
287
288 static ssize_t set_fan_min2(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
289 {
290         struct i2c_client *client = to_i2c_client(dev);
291         struct gl518_data *data = i2c_get_clientdata(client);
292         int regvalue;
293         unsigned long val = simple_strtoul(buf, NULL, 10);
294
295         mutex_lock(&data->update_lock);
296         regvalue = gl518_read_value(client, GL518_REG_FAN_LIMIT);
297         data->fan_min[1] = FAN_TO_REG(val,
298                 DIV_FROM_REG(data->fan_div[1]));
299         regvalue = (regvalue & 0xff00) | data->fan_min[1];
300         gl518_write_value(client, GL518_REG_FAN_LIMIT, regvalue);
301
302         data->beep_mask = gl518_read_value(client, GL518_REG_ALARM);
303         if (data->fan_min[1] == 0)
304                 data->alarm_mask &= ~0x40;
305         else
306                 data->alarm_mask |= 0x40;
307         data->beep_mask &= data->alarm_mask;
308         gl518_write_value(client, GL518_REG_ALARM, data->beep_mask);
309
310         mutex_unlock(&data->update_lock);
311         return count;
312 }
313
314 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
315 static DEVICE_ATTR(temp1_max, S_IWUSR|S_IRUGO, show_temp_max1, set_temp_max1);
316 static DEVICE_ATTR(temp1_max_hyst, S_IWUSR|S_IRUGO,
317         show_temp_hyst1, set_temp_hyst1);
318 static DEVICE_ATTR(fan1_auto, S_IWUSR|S_IRUGO, show_fan_auto1, set_fan_auto1);
319 static DEVICE_ATTR(fan1_input, S_IRUGO, show_fan_input1, NULL);
320 static DEVICE_ATTR(fan2_input, S_IRUGO, show_fan_input2, NULL);
321 static DEVICE_ATTR(fan1_min, S_IWUSR|S_IRUGO, show_fan_min1, set_fan_min1);
322 static DEVICE_ATTR(fan2_min, S_IWUSR|S_IRUGO, show_fan_min2, set_fan_min2);
323 static DEVICE_ATTR(fan1_div, S_IWUSR|S_IRUGO, show_fan_div1, set_fan_div1);
324 static DEVICE_ATTR(fan2_div, S_IWUSR|S_IRUGO, show_fan_div2, set_fan_div2);
325 static DEVICE_ATTR(in0_input, S_IRUGO, show_in_input0, NULL);
326 static DEVICE_ATTR(in1_input, S_IRUGO, show_in_input1, NULL);
327 static DEVICE_ATTR(in2_input, S_IRUGO, show_in_input2, NULL);
328 static DEVICE_ATTR(in3_input, S_IRUGO, show_in_input3, NULL);
329 static DEVICE_ATTR(in0_min, S_IWUSR|S_IRUGO, show_in_min0, set_in_min0);
330 static DEVICE_ATTR(in1_min, S_IWUSR|S_IRUGO, show_in_min1, set_in_min1);
331 static DEVICE_ATTR(in2_min, S_IWUSR|S_IRUGO, show_in_min2, set_in_min2);
332 static DEVICE_ATTR(in3_min, S_IWUSR|S_IRUGO, show_in_min3, set_in_min3);
333 static DEVICE_ATTR(in0_max, S_IWUSR|S_IRUGO, show_in_max0, set_in_max0);
334 static DEVICE_ATTR(in1_max, S_IWUSR|S_IRUGO, show_in_max1, set_in_max1);
335 static DEVICE_ATTR(in2_max, S_IWUSR|S_IRUGO, show_in_max2, set_in_max2);
336 static DEVICE_ATTR(in3_max, S_IWUSR|S_IRUGO, show_in_max3, set_in_max3);
337 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
338 static DEVICE_ATTR(beep_enable, S_IWUSR|S_IRUGO,
339         show_beep_enable, set_beep_enable);
340 static DEVICE_ATTR(beep_mask, S_IWUSR|S_IRUGO,
341         show_beep_mask, set_beep_mask);
342
343 /*
344  * Real code
345  */
346
347 static int gl518_attach_adapter(struct i2c_adapter *adapter)
348 {
349         if (!(adapter->class & I2C_CLASS_HWMON))
350                 return 0;
351         return i2c_probe(adapter, &addr_data, gl518_detect);
352 }
353
354 static int gl518_detect(struct i2c_adapter *adapter, int address, int kind)
355 {
356         int i;
357         struct i2c_client *new_client;
358         struct gl518_data *data;
359         int err = 0;
360
361         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
362                                      I2C_FUNC_SMBUS_WORD_DATA))
363                 goto exit;
364
365         /* OK. For now, we presume we have a valid client. We now create the
366            client structure, even though we cannot fill it completely yet.
367            But it allows us to access gl518_{read,write}_value. */
368
369         if (!(data = kzalloc(sizeof(struct gl518_data), GFP_KERNEL))) {
370                 err = -ENOMEM;
371                 goto exit;
372         }
373
374         new_client = &data->client;
375         i2c_set_clientdata(new_client, data);
376
377         new_client->addr = address;
378         new_client->adapter = adapter;
379         new_client->driver = &gl518_driver;
380         new_client->flags = 0;
381
382         /* Now, we do the remaining detection. */
383
384         if (kind < 0) {
385                 if ((gl518_read_value(new_client, GL518_REG_CHIP_ID) != 0x80)
386                  || (gl518_read_value(new_client, GL518_REG_CONF) & 0x80))
387                         goto exit_free;
388         }
389
390         /* Determine the chip type. */
391         if (kind <= 0) {
392                 i = gl518_read_value(new_client, GL518_REG_REVISION);
393                 if (i == 0x00) {
394                         kind = gl518sm_r00;
395                 } else if (i == 0x80) {
396                         kind = gl518sm_r80;
397                 } else {
398                         if (kind <= 0)
399                                 dev_info(&adapter->dev,
400                                     "Ignoring 'force' parameter for unknown "
401                                     "chip at adapter %d, address 0x%02x\n",
402                                     i2c_adapter_id(adapter), address);
403                         goto exit_free;
404                 }
405         }
406
407         /* Fill in the remaining client fields */
408         strlcpy(new_client->name, "gl518sm", I2C_NAME_SIZE);
409         data->type = kind;
410         data->valid = 0;
411         mutex_init(&data->update_lock);
412
413         /* Tell the I2C layer a new client has arrived */
414         if ((err = i2c_attach_client(new_client)))
415                 goto exit_free;
416
417         /* Initialize the GL518SM chip */
418         data->alarm_mask = 0xff;
419         data->voltage_in[0]=data->voltage_in[1]=data->voltage_in[2]=0;
420         gl518_init_client((struct i2c_client *) new_client);
421
422         /* Register sysfs hooks */
423         data->class_dev = hwmon_device_register(&new_client->dev);
424         if (IS_ERR(data->class_dev)) {
425                 err = PTR_ERR(data->class_dev);
426                 goto exit_detach;
427         }
428
429         device_create_file(&new_client->dev, &dev_attr_in0_input);
430         device_create_file(&new_client->dev, &dev_attr_in1_input);
431         device_create_file(&new_client->dev, &dev_attr_in2_input);
432         device_create_file(&new_client->dev, &dev_attr_in3_input);
433         device_create_file(&new_client->dev, &dev_attr_in0_min);
434         device_create_file(&new_client->dev, &dev_attr_in1_min);
435         device_create_file(&new_client->dev, &dev_attr_in2_min);
436         device_create_file(&new_client->dev, &dev_attr_in3_min);
437         device_create_file(&new_client->dev, &dev_attr_in0_max);
438         device_create_file(&new_client->dev, &dev_attr_in1_max);
439         device_create_file(&new_client->dev, &dev_attr_in2_max);
440         device_create_file(&new_client->dev, &dev_attr_in3_max);
441         device_create_file(&new_client->dev, &dev_attr_fan1_auto);
442         device_create_file(&new_client->dev, &dev_attr_fan1_input);
443         device_create_file(&new_client->dev, &dev_attr_fan2_input);
444         device_create_file(&new_client->dev, &dev_attr_fan1_min);
445         device_create_file(&new_client->dev, &dev_attr_fan2_min);
446         device_create_file(&new_client->dev, &dev_attr_fan1_div);
447         device_create_file(&new_client->dev, &dev_attr_fan2_div);
448         device_create_file(&new_client->dev, &dev_attr_temp1_input);
449         device_create_file(&new_client->dev, &dev_attr_temp1_max);
450         device_create_file(&new_client->dev, &dev_attr_temp1_max_hyst);
451         device_create_file(&new_client->dev, &dev_attr_alarms);
452         device_create_file(&new_client->dev, &dev_attr_beep_enable);
453         device_create_file(&new_client->dev, &dev_attr_beep_mask);
454
455         return 0;
456
457 /* OK, this is not exactly good programming practice, usually. But it is
458    very code-efficient in this case. */
459
460 exit_detach:
461         i2c_detach_client(new_client);
462 exit_free:
463         kfree(data);
464 exit:
465         return err;
466 }
467
468
469 /* Called when we have found a new GL518SM.
470    Note that we preserve D4:NoFan2 and D2:beep_enable. */
471 static void gl518_init_client(struct i2c_client *client)
472 {
473         /* Make sure we leave D7:Reset untouched */
474         u8 regvalue = gl518_read_value(client, GL518_REG_CONF) & 0x7f;
475
476         /* Comparator mode (D3=0), standby mode (D6=0) */
477         gl518_write_value(client, GL518_REG_CONF, (regvalue &= 0x37));
478
479         /* Never interrupts */
480         gl518_write_value(client, GL518_REG_MASK, 0x00);
481
482         /* Clear status register (D5=1), start (D6=1) */
483         gl518_write_value(client, GL518_REG_CONF, 0x20 | regvalue);
484         gl518_write_value(client, GL518_REG_CONF, 0x40 | regvalue);
485 }
486
487 static int gl518_detach_client(struct i2c_client *client)
488 {
489         struct gl518_data *data = i2c_get_clientdata(client);
490         int err;
491
492         hwmon_device_unregister(data->class_dev);
493
494         if ((err = i2c_detach_client(client)))
495                 return err;
496
497         kfree(data);
498         return 0;
499 }
500
501 /* Registers 0x07 to 0x0c are word-sized, others are byte-sized 
502    GL518 uses a high-byte first convention, which is exactly opposite to
503    the usual practice. */
504 static int gl518_read_value(struct i2c_client *client, u8 reg)
505 {
506         if ((reg >= 0x07) && (reg <= 0x0c))
507                 return swab16(i2c_smbus_read_word_data(client, reg));
508         else
509                 return i2c_smbus_read_byte_data(client, reg);
510 }
511
512 /* Registers 0x07 to 0x0c are word-sized, others are byte-sized 
513    GL518 uses a high-byte first convention, which is exactly opposite to
514    the usual practice. */
515 static int gl518_write_value(struct i2c_client *client, u8 reg, u16 value)
516 {
517         if ((reg >= 0x07) && (reg <= 0x0c))
518                 return i2c_smbus_write_word_data(client, reg, swab16(value));
519         else
520                 return i2c_smbus_write_byte_data(client, reg, value);
521 }
522
523 static struct gl518_data *gl518_update_device(struct device *dev)
524 {
525         struct i2c_client *client = to_i2c_client(dev);
526         struct gl518_data *data = i2c_get_clientdata(client);
527         int val;
528
529         mutex_lock(&data->update_lock);
530
531         if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
532             || !data->valid) {
533                 dev_dbg(&client->dev, "Starting gl518 update\n");
534
535                 data->alarms = gl518_read_value(client, GL518_REG_INT);
536                 data->beep_mask = gl518_read_value(client, GL518_REG_ALARM);
537
538                 val = gl518_read_value(client, GL518_REG_VDD_LIMIT);
539                 data->voltage_min[0] = val & 0xff;
540                 data->voltage_max[0] = (val >> 8) & 0xff;
541                 val = gl518_read_value(client, GL518_REG_VIN1_LIMIT);
542                 data->voltage_min[1] = val & 0xff;
543                 data->voltage_max[1] = (val >> 8) & 0xff;
544                 val = gl518_read_value(client, GL518_REG_VIN2_LIMIT);
545                 data->voltage_min[2] = val & 0xff;
546                 data->voltage_max[2] = (val >> 8) & 0xff;
547                 val = gl518_read_value(client, GL518_REG_VIN3_LIMIT);
548                 data->voltage_min[3] = val & 0xff;
549                 data->voltage_max[3] = (val >> 8) & 0xff;
550
551                 val = gl518_read_value(client, GL518_REG_FAN_COUNT);
552                 data->fan_in[0] = (val >> 8) & 0xff;
553                 data->fan_in[1] = val & 0xff;
554
555                 val = gl518_read_value(client, GL518_REG_FAN_LIMIT);
556                 data->fan_min[0] = (val >> 8) & 0xff;
557                 data->fan_min[1] = val & 0xff;
558
559                 data->temp_in = gl518_read_value(client, GL518_REG_TEMP_IN);
560                 data->temp_max =
561                     gl518_read_value(client, GL518_REG_TEMP_MAX);
562                 data->temp_hyst =
563                     gl518_read_value(client, GL518_REG_TEMP_HYST);
564
565                 val = gl518_read_value(client, GL518_REG_MISC);
566                 data->fan_div[0] = (val >> 6) & 0x03;
567                 data->fan_div[1] = (val >> 4) & 0x03;
568                 data->fan_auto1  = (val >> 3) & 0x01;
569
570                 data->alarms &= data->alarm_mask;
571
572                 val = gl518_read_value(client, GL518_REG_CONF);
573                 data->beep_enable = (val >> 2) & 1;
574
575                 if (data->type != gl518sm_r00) {
576                         data->voltage_in[0] =
577                             gl518_read_value(client, GL518_REG_VDD);
578                         data->voltage_in[1] =
579                             gl518_read_value(client, GL518_REG_VIN1);
580                         data->voltage_in[2] =
581                             gl518_read_value(client, GL518_REG_VIN2);
582                 }
583                 data->voltage_in[3] =
584                     gl518_read_value(client, GL518_REG_VIN3);
585
586                 data->last_updated = jiffies;
587                 data->valid = 1;
588         }
589
590         mutex_unlock(&data->update_lock);
591
592         return data;
593 }
594
595 static int __init sensors_gl518sm_init(void)
596 {
597         return i2c_add_driver(&gl518_driver);
598 }
599
600 static void __exit sensors_gl518sm_exit(void)
601 {
602         i2c_del_driver(&gl518_driver);
603 }
604
605 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>, "
606         "Kyosti Malkki <kmalkki@cc.hut.fi> and "
607         "Hong-Gunn Chew <hglinux@gunnet.org>");
608 MODULE_DESCRIPTION("GL518SM driver");
609 MODULE_LICENSE("GPL");
610
611 module_init(sensors_gl518sm_init);
612 module_exit(sensors_gl518sm_exit);