[PATCH] I2C: refactor message in i2c_detach_client
[safe/jmp/linux-2.6] / drivers / hwmon / smsc47m1.c
1 /*
2     smsc47m1.c - Part of lm_sensors, Linux kernel modules
3                  for hardware monitoring
4
5     Supports the SMSC LPC47B27x, LPC47M10x, LPC47M13x and LPC47M14x
6     Super-I/O chips.
7
8     Copyright (C) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>
9     Copyright (C) 2004 Jean Delvare <khali@linux-fr.org>
10     Ported to Linux 2.6 by Gabriele Gorla <gorlik@yahoo.com>
11                         and Jean Delvare
12
13     This program is free software; you can redistribute it and/or modify
14     it under the terms of the GNU General Public License as published by
15     the Free Software Foundation; either version 2 of the License, or
16     (at your option) any later version.
17
18     This program is distributed in the hope that it will be useful,
19     but WITHOUT ANY WARRANTY; without even the implied warranty of
20     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21     GNU General Public License for more details.
22
23     You should have received a copy of the GNU General Public License
24     along with this program; if not, write to the Free Software
25     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26 */
27
28 #include <linux/module.h>
29 #include <linux/slab.h>
30 #include <linux/ioport.h>
31 #include <linux/jiffies.h>
32 #include <linux/i2c.h>
33 #include <linux/i2c-isa.h>
34 #include <linux/i2c-sensor.h>
35 #include <linux/hwmon.h>
36 #include <linux/err.h>
37 #include <linux/init.h>
38 #include <asm/io.h>
39
40 /* Address is autodetected, there is no default value */
41 static unsigned short address;
42
43 /* Super-I/0 registers and commands */
44
45 #define REG     0x2e    /* The register to read/write */
46 #define VAL     0x2f    /* The value to read/write */
47
48 static inline void
49 superio_outb(int reg, int val)
50 {
51         outb(reg, REG);
52         outb(val, VAL);
53 }
54
55 static inline int
56 superio_inb(int reg)
57 {
58         outb(reg, REG);
59         return inb(VAL);
60 }
61
62 /* logical device for fans is 0x0A */
63 #define superio_select() superio_outb(0x07, 0x0A)
64
65 static inline void
66 superio_enter(void)
67 {
68         outb(0x55, REG);
69 }
70
71 static inline void
72 superio_exit(void)
73 {
74         outb(0xAA, REG);
75 }
76
77 #define SUPERIO_REG_ACT         0x30
78 #define SUPERIO_REG_BASE        0x60
79 #define SUPERIO_REG_DEVID       0x20
80
81 /* Logical device registers */
82
83 #define SMSC_EXTENT             0x80
84
85 /* nr is 0 or 1 in the macros below */
86 #define SMSC47M1_REG_ALARM              0x04
87 #define SMSC47M1_REG_TPIN(nr)           (0x34 - (nr))
88 #define SMSC47M1_REG_PPIN(nr)           (0x36 - (nr))
89 #define SMSC47M1_REG_PWM(nr)            (0x56 + (nr))
90 #define SMSC47M1_REG_FANDIV             0x58
91 #define SMSC47M1_REG_FAN(nr)            (0x59 + (nr))
92 #define SMSC47M1_REG_FAN_PRELOAD(nr)    (0x5B + (nr))
93
94 #define MIN_FROM_REG(reg,div)           ((reg)>=192 ? 0 : \
95                                          983040/((192-(reg))*(div)))
96 #define FAN_FROM_REG(reg,div,preload)   ((reg)<=(preload) || (reg)==255 ? 0 : \
97                                          983040/(((reg)-(preload))*(div)))
98 #define DIV_FROM_REG(reg)               (1 << (reg))
99 #define PWM_FROM_REG(reg)               (((reg) & 0x7E) << 1)
100 #define PWM_EN_FROM_REG(reg)            ((~(reg)) & 0x01)
101 #define PWM_TO_REG(reg)                 (((reg) >> 1) & 0x7E)
102
103 struct smsc47m1_data {
104         struct i2c_client client;
105         struct class_device *class_dev;
106         struct semaphore lock;
107
108         struct semaphore update_lock;
109         unsigned long last_updated;     /* In jiffies */
110
111         u8 fan[2];              /* Register value */
112         u8 fan_preload[2];      /* Register value */
113         u8 fan_div[2];          /* Register encoding, shifted right */
114         u8 alarms;              /* Register encoding */
115         u8 pwm[2];              /* Register value (bit 7 is enable) */
116 };
117
118
119 static int smsc47m1_detect(struct i2c_adapter *adapter);
120 static int smsc47m1_detach_client(struct i2c_client *client);
121
122 static int smsc47m1_read_value(struct i2c_client *client, u8 reg);
123 static void smsc47m1_write_value(struct i2c_client *client, u8 reg, u8 value);
124
125 static struct smsc47m1_data *smsc47m1_update_device(struct device *dev,
126                 int init);
127
128
129 static struct i2c_driver smsc47m1_driver = {
130         .owner          = THIS_MODULE,
131         .name           = "smsc47m1",
132         .attach_adapter = smsc47m1_detect,
133         .detach_client  = smsc47m1_detach_client,
134 };
135
136 /* nr is 0 or 1 in the callback functions below */
137
138 static ssize_t get_fan(struct device *dev, char *buf, int nr)
139 {
140         struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
141         /* This chip (stupidly) stops monitoring fan speed if PWM is
142            enabled and duty cycle is 0%. This is fine if the monitoring
143            and control concern the same fan, but troublesome if they are
144            not (which could as well happen). */
145         int rpm = (data->pwm[nr] & 0x7F) == 0x00 ? 0 :
146                   FAN_FROM_REG(data->fan[nr],
147                                DIV_FROM_REG(data->fan_div[nr]),
148                                data->fan_preload[nr]);
149         return sprintf(buf, "%d\n", rpm);
150 }
151
152 static ssize_t get_fan_min(struct device *dev, char *buf, int nr)
153 {
154         struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
155         int rpm = MIN_FROM_REG(data->fan_preload[nr],
156                                DIV_FROM_REG(data->fan_div[nr]));
157         return sprintf(buf, "%d\n", rpm);
158 }
159
160 static ssize_t get_fan_div(struct device *dev, char *buf, int nr)
161 {
162         struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
163         return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[nr]));
164 }
165
166 static ssize_t get_pwm(struct device *dev, char *buf, int nr)
167 {
168         struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
169         return sprintf(buf, "%d\n", PWM_FROM_REG(data->pwm[nr]));
170 }
171
172 static ssize_t get_pwm_en(struct device *dev, char *buf, int nr)
173 {
174         struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
175         return sprintf(buf, "%d\n", PWM_EN_FROM_REG(data->pwm[nr]));
176 }
177
178 static ssize_t get_alarms(struct device *dev, struct device_attribute *attr, char *buf)
179 {
180         struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
181         return sprintf(buf, "%d\n", data->alarms);
182 }
183
184 static ssize_t set_fan_min(struct device *dev, const char *buf,
185                 size_t count, int nr)
186 {
187         struct i2c_client *client = to_i2c_client(dev);
188         struct smsc47m1_data *data = i2c_get_clientdata(client);
189         long rpmdiv, val = simple_strtol(buf, NULL, 10);
190
191         down(&data->update_lock);
192         rpmdiv = val * DIV_FROM_REG(data->fan_div[nr]);
193
194         if (983040 > 192 * rpmdiv || 2 * rpmdiv > 983040) {
195                 up(&data->update_lock);
196                 return -EINVAL;
197         }
198
199         data->fan_preload[nr] = 192 - ((983040 + rpmdiv / 2) / rpmdiv);
200         smsc47m1_write_value(client, SMSC47M1_REG_FAN_PRELOAD(nr),
201                              data->fan_preload[nr]);
202         up(&data->update_lock);
203
204         return count;
205 }
206
207 /* Note: we save and restore the fan minimum here, because its value is
208    determined in part by the fan clock divider.  This follows the principle
209    of least suprise; the user doesn't expect the fan minimum to change just
210    because the divider changed. */
211 static ssize_t set_fan_div(struct device *dev, const char *buf,
212                 size_t count, int nr)
213 {
214         struct i2c_client *client = to_i2c_client(dev);
215         struct smsc47m1_data *data = i2c_get_clientdata(client);
216
217         long new_div = simple_strtol(buf, NULL, 10), tmp;
218         u8 old_div = DIV_FROM_REG(data->fan_div[nr]);
219
220         if (new_div == old_div) /* No change */
221                 return count;
222
223         down(&data->update_lock);
224         switch (new_div) {
225         case 1: data->fan_div[nr] = 0; break;
226         case 2: data->fan_div[nr] = 1; break;
227         case 4: data->fan_div[nr] = 2; break;
228         case 8: data->fan_div[nr] = 3; break;
229         default:
230                 up(&data->update_lock);
231                 return -EINVAL;
232         }
233
234         tmp = smsc47m1_read_value(client, SMSC47M1_REG_FANDIV) & 0x0F;
235         tmp |= (data->fan_div[0] << 4) | (data->fan_div[1] << 6);
236         smsc47m1_write_value(client, SMSC47M1_REG_FANDIV, tmp);
237
238         /* Preserve fan min */
239         tmp = 192 - (old_div * (192 - data->fan_preload[nr])
240                      + new_div / 2) / new_div;
241         data->fan_preload[nr] = SENSORS_LIMIT(tmp, 0, 191);
242         smsc47m1_write_value(client, SMSC47M1_REG_FAN_PRELOAD(nr),
243                              data->fan_preload[nr]);
244         up(&data->update_lock);
245
246         return count;
247 }
248
249 static ssize_t set_pwm(struct device *dev, const char *buf,
250                 size_t count, int nr)
251 {
252         struct i2c_client *client = to_i2c_client(dev);
253         struct smsc47m1_data *data = i2c_get_clientdata(client);
254
255         long val = simple_strtol(buf, NULL, 10);
256
257         if (val < 0 || val > 255)
258                 return -EINVAL;
259
260         down(&data->update_lock);
261         data->pwm[nr] &= 0x81; /* Preserve additional bits */
262         data->pwm[nr] |= PWM_TO_REG(val);
263         smsc47m1_write_value(client, SMSC47M1_REG_PWM(nr),
264                              data->pwm[nr]);
265         up(&data->update_lock);
266
267         return count;
268 }
269
270 static ssize_t set_pwm_en(struct device *dev, const char *buf,
271                 size_t count, int nr)
272 {
273         struct i2c_client *client = to_i2c_client(dev);
274         struct smsc47m1_data *data = i2c_get_clientdata(client);
275
276         long val = simple_strtol(buf, NULL, 10);
277         
278         if (val != 0 && val != 1)
279                 return -EINVAL;
280
281         down(&data->update_lock);
282         data->pwm[nr] &= 0xFE; /* preserve the other bits */
283         data->pwm[nr] |= !val;
284         smsc47m1_write_value(client, SMSC47M1_REG_PWM(nr),
285                              data->pwm[nr]);
286         up(&data->update_lock);
287
288         return count;
289 }
290
291 #define fan_present(offset)                                             \
292 static ssize_t get_fan##offset (struct device *dev, struct device_attribute *attr, char *buf)           \
293 {                                                                       \
294         return get_fan(dev, buf, offset - 1);                           \
295 }                                                                       \
296 static ssize_t get_fan##offset##_min (struct device *dev, struct device_attribute *attr, char *buf)     \
297 {                                                                       \
298         return get_fan_min(dev, buf, offset - 1);                       \
299 }                                                                       \
300 static ssize_t set_fan##offset##_min (struct device *dev, struct device_attribute *attr,                \
301                 const char *buf, size_t count)                          \
302 {                                                                       \
303         return set_fan_min(dev, buf, count, offset - 1);                \
304 }                                                                       \
305 static ssize_t get_fan##offset##_div (struct device *dev, struct device_attribute *attr, char *buf)     \
306 {                                                                       \
307         return get_fan_div(dev, buf, offset - 1);                       \
308 }                                                                       \
309 static ssize_t set_fan##offset##_div (struct device *dev, struct device_attribute *attr,                \
310                 const char *buf, size_t count)                          \
311 {                                                                       \
312         return set_fan_div(dev, buf, count, offset - 1);                \
313 }                                                                       \
314 static ssize_t get_pwm##offset (struct device *dev, struct device_attribute *attr, char *buf)           \
315 {                                                                       \
316         return get_pwm(dev, buf, offset - 1);                           \
317 }                                                                       \
318 static ssize_t set_pwm##offset (struct device *dev, struct device_attribute *attr,                      \
319                 const char *buf, size_t count)                          \
320 {                                                                       \
321         return set_pwm(dev, buf, count, offset - 1);                    \
322 }                                                                       \
323 static ssize_t get_pwm##offset##_en (struct device *dev, struct device_attribute *attr, char *buf)      \
324 {                                                                       \
325         return get_pwm_en(dev, buf, offset - 1);                        \
326 }                                                                       \
327 static ssize_t set_pwm##offset##_en (struct device *dev, struct device_attribute *attr,         \
328                 const char *buf, size_t count)                          \
329 {                                                                       \
330         return set_pwm_en(dev, buf, count, offset - 1);                 \
331 }                                                                       \
332 static DEVICE_ATTR(fan##offset##_input, S_IRUGO, get_fan##offset,       \
333                 NULL);                                                  \
334 static DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR,                \
335                 get_fan##offset##_min, set_fan##offset##_min);          \
336 static DEVICE_ATTR(fan##offset##_div, S_IRUGO | S_IWUSR,                \
337                 get_fan##offset##_div, set_fan##offset##_div);          \
338 static DEVICE_ATTR(pwm##offset, S_IRUGO | S_IWUSR,                      \
339                 get_pwm##offset, set_pwm##offset);                      \
340 static DEVICE_ATTR(pwm##offset##_enable, S_IRUGO | S_IWUSR,             \
341                 get_pwm##offset##_en, set_pwm##offset##_en);
342
343 fan_present(1);
344 fan_present(2);
345
346 static DEVICE_ATTR(alarms, S_IRUGO, get_alarms, NULL);
347
348 static int smsc47m1_find(unsigned short *addr)
349 {
350         u8 val;
351
352         superio_enter();
353         val = superio_inb(SUPERIO_REG_DEVID);
354
355         /*
356          * SMSC LPC47M10x/LPC47M13x (device id 0x59), LPC47M14x (device id
357          * 0x5F) and LPC47B27x (device id 0x51) have fan control.
358          * The LPC47M15x and LPC47M192 chips "with hardware monitoring block"
359          * can do much more besides (device id 0x60).
360          */
361         if (val == 0x51)
362                 printk(KERN_INFO "smsc47m1: Found SMSC LPC47B27x\n");
363         else if (val == 0x59)
364                 printk(KERN_INFO "smsc47m1: Found SMSC LPC47M10x/LPC47M13x\n");
365         else if (val == 0x5F)
366                 printk(KERN_INFO "smsc47m1: Found SMSC LPC47M14x\n");
367         else if (val == 0x60)
368                 printk(KERN_INFO "smsc47m1: Found SMSC LPC47M15x/LPC47M192\n");
369         else {
370                 superio_exit();
371                 return -ENODEV;
372         }
373
374         superio_select();
375         *addr = (superio_inb(SUPERIO_REG_BASE) << 8)
376               |  superio_inb(SUPERIO_REG_BASE + 1);
377         val = superio_inb(SUPERIO_REG_ACT);
378         if (*addr == 0 || (val & 0x01) == 0) {
379                 printk(KERN_INFO "smsc47m1: Device is disabled, will not use\n");
380                 superio_exit();
381                 return -ENODEV;
382         }
383
384         superio_exit();
385         return 0;
386 }
387
388 static int smsc47m1_detect(struct i2c_adapter *adapter)
389 {
390         struct i2c_client *new_client;
391         struct smsc47m1_data *data;
392         int err = 0;
393         int fan1, fan2, pwm1, pwm2;
394
395         if (!request_region(address, SMSC_EXTENT, smsc47m1_driver.name)) {
396                 dev_err(&adapter->dev, "Region 0x%x already in use!\n", address);
397                 return -EBUSY;
398         }
399
400         if (!(data = kmalloc(sizeof(struct smsc47m1_data), GFP_KERNEL))) {
401                 err = -ENOMEM;
402                 goto error_release;
403         }
404         memset(data, 0x00, sizeof(struct smsc47m1_data));
405
406         new_client = &data->client;
407         i2c_set_clientdata(new_client, data);
408         new_client->addr = address;
409         init_MUTEX(&data->lock);
410         new_client->adapter = adapter;
411         new_client->driver = &smsc47m1_driver;
412         new_client->flags = 0;
413
414         strlcpy(new_client->name, "smsc47m1", I2C_NAME_SIZE);
415         init_MUTEX(&data->update_lock);
416
417         /* If no function is properly configured, there's no point in
418            actually registering the chip. */
419         fan1 = (smsc47m1_read_value(new_client, SMSC47M1_REG_TPIN(0)) & 0x05)
420                == 0x05;
421         fan2 = (smsc47m1_read_value(new_client, SMSC47M1_REG_TPIN(1)) & 0x05)
422                == 0x05;
423         pwm1 = (smsc47m1_read_value(new_client, SMSC47M1_REG_PPIN(0)) & 0x05)
424                == 0x04;
425         pwm2 = (smsc47m1_read_value(new_client, SMSC47M1_REG_PPIN(1)) & 0x05)
426                == 0x04;
427         if (!(fan1 || fan2 || pwm1 || pwm2)) {
428                 dev_warn(&new_client->dev, "Device is not configured, will not use\n");
429                 err = -ENODEV;
430                 goto error_free;
431         }
432
433         if ((err = i2c_attach_client(new_client)))
434                 goto error_free;
435
436         /* Some values (fan min, clock dividers, pwm registers) may be
437            needed before any update is triggered, so we better read them
438            at least once here. We don't usually do it that way, but in
439            this particular case, manually reading 5 registers out of 8
440            doesn't make much sense and we're better using the existing
441            function. */
442         smsc47m1_update_device(&new_client->dev, 1);
443
444         /* Register sysfs hooks */
445         data->class_dev = hwmon_device_register(&new_client->dev);
446         if (IS_ERR(data->class_dev)) {
447                 err = PTR_ERR(data->class_dev);
448                 goto error_detach;
449         }
450
451         if (fan1) {
452                 device_create_file(&new_client->dev, &dev_attr_fan1_input);
453                 device_create_file(&new_client->dev, &dev_attr_fan1_min);
454                 device_create_file(&new_client->dev, &dev_attr_fan1_div);
455         } else
456                 dev_dbg(&new_client->dev, "Fan 1 not enabled by hardware, "
457                         "skipping\n");
458
459         if (fan2) {
460                 device_create_file(&new_client->dev, &dev_attr_fan2_input);
461                 device_create_file(&new_client->dev, &dev_attr_fan2_min);
462                 device_create_file(&new_client->dev, &dev_attr_fan2_div);
463         } else
464                 dev_dbg(&new_client->dev, "Fan 2 not enabled by hardware, "
465                         "skipping\n");
466
467         if (pwm1) {
468                 device_create_file(&new_client->dev, &dev_attr_pwm1);
469                 device_create_file(&new_client->dev, &dev_attr_pwm1_enable);
470         } else
471                 dev_dbg(&new_client->dev, "PWM 1 not enabled by hardware, "
472                         "skipping\n");
473         if (pwm2) {
474                 device_create_file(&new_client->dev, &dev_attr_pwm2);
475                 device_create_file(&new_client->dev, &dev_attr_pwm2_enable);
476         } else
477                 dev_dbg(&new_client->dev, "PWM 2 not enabled by hardware, "
478                         "skipping\n");
479
480         device_create_file(&new_client->dev, &dev_attr_alarms);
481
482         return 0;
483
484 error_detach:
485         i2c_detach_client(new_client);
486 error_free:
487         kfree(data);
488 error_release:
489         release_region(address, SMSC_EXTENT);
490         return err;
491 }
492
493 static int smsc47m1_detach_client(struct i2c_client *client)
494 {
495         struct smsc47m1_data *data = i2c_get_clientdata(client);
496         int err;
497
498         hwmon_device_unregister(data->class_dev);
499
500         if ((err = i2c_detach_client(client)))
501                 return err;
502
503         release_region(client->addr, SMSC_EXTENT);
504         kfree(data);
505
506         return 0;
507 }
508
509 static int smsc47m1_read_value(struct i2c_client *client, u8 reg)
510 {
511         int res;
512
513         down(&((struct smsc47m1_data *) i2c_get_clientdata(client))->lock);
514         res = inb_p(client->addr + reg);
515         up(&((struct smsc47m1_data *) i2c_get_clientdata(client))->lock);
516         return res;
517 }
518
519 static void smsc47m1_write_value(struct i2c_client *client, u8 reg, u8 value)
520 {
521         down(&((struct smsc47m1_data *) i2c_get_clientdata(client))->lock);
522         outb_p(value, client->addr + reg);
523         up(&((struct smsc47m1_data *) i2c_get_clientdata(client))->lock);
524 }
525
526 static struct smsc47m1_data *smsc47m1_update_device(struct device *dev,
527                 int init)
528 {
529         struct i2c_client *client = to_i2c_client(dev);
530         struct smsc47m1_data *data = i2c_get_clientdata(client);
531
532         down(&data->update_lock);
533
534         if (time_after(jiffies, data->last_updated + HZ + HZ / 2) || init) {
535                 int i;
536
537                 for (i = 0; i < 2; i++) {
538                         data->fan[i] = smsc47m1_read_value(client,
539                                        SMSC47M1_REG_FAN(i));
540                         data->fan_preload[i] = smsc47m1_read_value(client,
541                                                SMSC47M1_REG_FAN_PRELOAD(i));
542                         data->pwm[i] = smsc47m1_read_value(client,
543                                        SMSC47M1_REG_PWM(i));
544                 }
545
546                 i = smsc47m1_read_value(client, SMSC47M1_REG_FANDIV);
547                 data->fan_div[0] = (i >> 4) & 0x03;
548                 data->fan_div[1] = i >> 6;
549
550                 data->alarms = smsc47m1_read_value(client,
551                                SMSC47M1_REG_ALARM) >> 6;
552                 /* Clear alarms if needed */
553                 if (data->alarms)
554                         smsc47m1_write_value(client, SMSC47M1_REG_ALARM, 0xC0);
555
556                 data->last_updated = jiffies;
557         }
558
559         up(&data->update_lock);
560         return data;
561 }
562
563 static int __init sm_smsc47m1_init(void)
564 {
565         if (smsc47m1_find(&address)) {
566                 return -ENODEV;
567         }
568
569         return i2c_isa_add_driver(&smsc47m1_driver);
570 }
571
572 static void __exit sm_smsc47m1_exit(void)
573 {
574         i2c_isa_del_driver(&smsc47m1_driver);
575 }
576
577 MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>");
578 MODULE_DESCRIPTION("SMSC LPC47M1xx fan sensors driver");
579 MODULE_LICENSE("GPL");
580
581 module_init(sm_smsc47m1_init);
582 module_exit(sm_smsc47m1_exit);