Documentation cleanup: trivial misspelling, punctuation, and grammar corrections.
[linux-2.6] / drivers / hwmon / ibmpex.c
1 /*
2  * A hwmon driver for the IBM PowerExecutive temperature/power sensors
3  * Copyright (C) 2007 IBM
4  *
5  * Author: Darrick J. Wong <djwong@us.ibm.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21
22 #include <linux/ipmi.h>
23 #include <linux/module.h>
24 #include <linux/hwmon.h>
25 #include <linux/hwmon-sysfs.h>
26 #include <linux/jiffies.h>
27 #include <linux/mutex.h>
28
29 #define REFRESH_INTERVAL        (2 * HZ)
30 #define DRVNAME                 "ibmpex"
31
32 #define PEX_GET_VERSION         1
33 #define PEX_GET_SENSOR_COUNT    2
34 #define PEX_GET_SENSOR_NAME     3
35 #define PEX_RESET_HIGH_LOW      4
36 #define PEX_GET_SENSOR_DATA     6
37
38 #define PEX_NET_FUNCTION        0x3A
39 #define PEX_COMMAND             0x3C
40
41 static inline u16 extract_value(const char *data, int offset)
42 {
43         return be16_to_cpup((u16 *)&data[offset]);
44 }
45
46 #define TEMP_SENSOR             1
47 #define POWER_SENSOR            2
48
49 #define PEX_SENSOR_TYPE_LEN     3
50 static u8 const power_sensor_sig[] = {0x70, 0x77, 0x72};
51 static u8 const temp_sensor_sig[]  = {0x74, 0x65, 0x6D};
52
53 #define PEX_MULT_LEN            2
54 static u8 const watt_sensor_sig[]  = {0x41, 0x43};
55
56 #define PEX_NUM_SENSOR_FUNCS    3
57 static char const * const power_sensor_name_templates[] = {
58         "%s%d_average",
59         "%s%d_average_lowest",
60         "%s%d_average_highest"
61 };
62 static char const * const temp_sensor_name_templates[] = {
63         "%s%d_input",
64         "%s%d_input_lowest",
65         "%s%d_input_highest"
66 };
67
68 static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
69 static void ibmpex_register_bmc(int iface, struct device *dev);
70 static void ibmpex_bmc_gone(int iface);
71
72 struct ibmpex_sensor_data {
73         int                     in_use;
74         s16                     values[PEX_NUM_SENSOR_FUNCS];
75         int                     multiplier;
76
77         struct sensor_device_attribute_2        attr[PEX_NUM_SENSOR_FUNCS];
78 };
79
80 struct ibmpex_bmc_data {
81         struct list_head        list;
82         struct device           *hwmon_dev;
83         struct device           *bmc_device;
84         struct mutex            lock;
85         char                    valid;
86         unsigned long           last_updated;   /* In jiffies */
87
88         struct ipmi_addr        address;
89         struct completion       read_complete;
90         ipmi_user_t             user;
91         int                     interface;
92
93         struct kernel_ipmi_msg  tx_message;
94         unsigned char           tx_msg_data[IPMI_MAX_MSG_LENGTH];
95         long                    tx_msgid;
96
97         unsigned char           rx_msg_data[IPMI_MAX_MSG_LENGTH];
98         unsigned long           rx_msg_len;
99         unsigned char           rx_result;
100         int                     rx_recv_type;
101
102         unsigned char           sensor_major;
103         unsigned char           sensor_minor;
104
105         unsigned char           num_sensors;
106         struct ibmpex_sensor_data       *sensors;
107 };
108
109 struct ibmpex_driver_data {
110         struct list_head        bmc_data;
111         struct ipmi_smi_watcher bmc_events;
112         struct ipmi_user_hndl   ipmi_hndlrs;
113 };
114
115 static struct ibmpex_driver_data driver_data = {
116         .bmc_data = LIST_HEAD_INIT(driver_data.bmc_data),
117         .bmc_events = {
118                 .owner = THIS_MODULE,
119                 .new_smi = ibmpex_register_bmc,
120                 .smi_gone = ibmpex_bmc_gone,
121         },
122         .ipmi_hndlrs = {
123                 .ipmi_recv_hndl = ibmpex_msg_handler,
124         },
125 };
126
127 static int ibmpex_send_message(struct ibmpex_bmc_data *data)
128 {
129         int err;
130
131         err = ipmi_validate_addr(&data->address, sizeof(data->address));
132         if (err)
133                 goto out;
134
135         data->tx_msgid++;
136         err = ipmi_request_settime(data->user, &data->address, data->tx_msgid,
137                                    &data->tx_message, data, 0, 0, 0);
138         if (err)
139                 goto out1;
140
141         return 0;
142 out1:
143         dev_err(data->bmc_device, "request_settime=%x\n", err);
144         return err;
145 out:
146         dev_err(data->bmc_device, "validate_addr=%x\n", err);
147         return err;
148 }
149
150 static int ibmpex_ver_check(struct ibmpex_bmc_data *data)
151 {
152         data->tx_msg_data[0] = PEX_GET_VERSION;
153         data->tx_message.data_len = 1;
154         ibmpex_send_message(data);
155
156         wait_for_completion(&data->read_complete);
157
158         if (data->rx_result || data->rx_msg_len != 6)
159                 return -ENOENT;
160
161         data->sensor_major = data->rx_msg_data[0];
162         data->sensor_minor = data->rx_msg_data[1];
163
164         dev_info(data->bmc_device, "Found BMC with sensor interface "
165                  "v%d.%d %d-%02d-%02d on interface %d\n",
166                  data->sensor_major,
167                  data->sensor_minor,
168                  extract_value(data->rx_msg_data, 2),
169                  data->rx_msg_data[4],
170                  data->rx_msg_data[5],
171                  data->interface);
172
173         return 0;
174 }
175
176 static int ibmpex_query_sensor_count(struct ibmpex_bmc_data *data)
177 {
178         data->tx_msg_data[0] = PEX_GET_SENSOR_COUNT;
179         data->tx_message.data_len = 1;
180         ibmpex_send_message(data);
181
182         wait_for_completion(&data->read_complete);
183
184         if (data->rx_result || data->rx_msg_len != 1)
185                 return -ENOENT;
186
187         return data->rx_msg_data[0];
188 }
189
190 static int ibmpex_query_sensor_name(struct ibmpex_bmc_data *data, int sensor)
191 {
192         data->tx_msg_data[0] = PEX_GET_SENSOR_NAME;
193         data->tx_msg_data[1] = sensor;
194         data->tx_message.data_len = 2;
195         ibmpex_send_message(data);
196
197         wait_for_completion(&data->read_complete);
198
199         if (data->rx_result || data->rx_msg_len < 1)
200                 return -ENOENT;
201
202         return 0;
203 }
204
205 static int ibmpex_query_sensor_data(struct ibmpex_bmc_data *data, int sensor)
206 {
207         data->tx_msg_data[0] = PEX_GET_SENSOR_DATA;
208         data->tx_msg_data[1] = sensor;
209         data->tx_message.data_len = 2;
210         ibmpex_send_message(data);
211
212         wait_for_completion(&data->read_complete);
213
214         if (data->rx_result || data->rx_msg_len < 26) {
215                 dev_err(data->bmc_device, "Error reading sensor %d.\n",
216                         sensor);
217                 return -ENOENT;
218         }
219
220         return 0;
221 }
222
223 static int ibmpex_reset_high_low_data(struct ibmpex_bmc_data *data)
224 {
225         data->tx_msg_data[0] = PEX_RESET_HIGH_LOW;
226         data->tx_message.data_len = 1;
227         ibmpex_send_message(data);
228
229         wait_for_completion(&data->read_complete);
230
231         return 0;
232 }
233
234 static void ibmpex_update_device(struct ibmpex_bmc_data *data)
235 {
236         int i, err;
237
238         mutex_lock(&data->lock);
239         if (time_before(jiffies, data->last_updated + REFRESH_INTERVAL) &&
240             data->valid)
241                 goto out;
242
243         for (i = 0; i < data->num_sensors; i++) {
244                 if (!data->sensors[i].in_use)
245                         continue;
246                 err = ibmpex_query_sensor_data(data, i);
247                 if (err)
248                         continue;
249                 data->sensors[i].values[0] =
250                         extract_value(data->rx_msg_data, 16);
251                 data->sensors[i].values[1] =
252                         extract_value(data->rx_msg_data, 18);
253                 data->sensors[i].values[2] =
254                         extract_value(data->rx_msg_data, 20);
255         }
256
257         data->last_updated = jiffies;
258         data->valid = 1;
259
260 out:
261         mutex_unlock(&data->lock);
262 }
263
264 static struct ibmpex_bmc_data *get_bmc_data(int iface)
265 {
266         struct ibmpex_bmc_data *p, *next;
267
268         list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
269                 if (p->interface == iface)
270                         return p;
271
272         return NULL;
273 }
274
275 static ssize_t show_name(struct device *dev, struct device_attribute *devattr,
276                          char *buf)
277 {
278         return sprintf(buf, "%s\n", DRVNAME);
279 }
280 static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, 0);
281
282 static ssize_t ibmpex_show_sensor(struct device *dev,
283                                   struct device_attribute *devattr,
284                                   char *buf)
285 {
286         struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
287         struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
288         int mult = data->sensors[attr->index].multiplier;
289         ibmpex_update_device(data);
290
291         return sprintf(buf, "%d\n",
292                        data->sensors[attr->index].values[attr->nr] * mult);
293 }
294
295 static ssize_t ibmpex_reset_high_low(struct device *dev,
296                                      struct device_attribute *devattr,
297                                      const char *buf,
298                                      size_t count)
299 {
300         struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
301
302         ibmpex_reset_high_low_data(data);
303
304         return count;
305 }
306
307 static SENSOR_DEVICE_ATTR(reset_high_low, S_IWUSR, NULL,
308                           ibmpex_reset_high_low, 0);
309
310 static int is_power_sensor(const char *sensor_id, int len)
311 {
312         if (len < PEX_SENSOR_TYPE_LEN)
313                 return 0;
314
315         if (!memcmp(sensor_id, power_sensor_sig, PEX_SENSOR_TYPE_LEN))
316                 return 1;
317         return 0;
318 }
319
320 static int is_temp_sensor(const char *sensor_id, int len)
321 {
322         if (len < PEX_SENSOR_TYPE_LEN)
323                 return 0;
324
325         if (!memcmp(sensor_id, temp_sensor_sig, PEX_SENSOR_TYPE_LEN))
326                 return 1;
327         return 0;
328 }
329
330 static int power_sensor_multiplier(struct ibmpex_bmc_data *data,
331                                    const char *sensor_id, int len)
332 {
333         int i;
334
335         if (data->sensor_major == 2)
336                 return 1000000;
337
338         for (i = PEX_SENSOR_TYPE_LEN; i < len - 1; i++)
339                 if (!memcmp(&sensor_id[i], watt_sensor_sig, PEX_MULT_LEN))
340                         return 1000000;
341
342         return 100000;
343 }
344
345 static int create_sensor(struct ibmpex_bmc_data *data, int type,
346                          int counter, int sensor, int func)
347 {
348         int err;
349         char *n;
350
351         n = kmalloc(32, GFP_KERNEL);
352         if (!n)
353                 return -ENOMEM;
354
355         if (type == TEMP_SENSOR)
356                 sprintf(n, temp_sensor_name_templates[func], "temp", counter);
357         else if (type == POWER_SENSOR)
358                 sprintf(n, power_sensor_name_templates[func], "power", counter);
359
360         data->sensors[sensor].attr[func].dev_attr.attr.name = n;
361         data->sensors[sensor].attr[func].dev_attr.attr.mode = S_IRUGO;
362         data->sensors[sensor].attr[func].dev_attr.show = ibmpex_show_sensor;
363         data->sensors[sensor].attr[func].index = sensor;
364         data->sensors[sensor].attr[func].nr = func;
365
366         err = device_create_file(data->bmc_device,
367                                  &data->sensors[sensor].attr[func].dev_attr);
368         if (err) {
369                 data->sensors[sensor].attr[func].dev_attr.attr.name = NULL;
370                 kfree(n);
371                 return err;
372         }
373
374         return 0;
375 }
376
377 static int ibmpex_find_sensors(struct ibmpex_bmc_data *data)
378 {
379         int i, j, err;
380         int sensor_type;
381         int sensor_counter;
382         int num_power = 0;
383         int num_temp = 0;
384
385         err = ibmpex_query_sensor_count(data);
386         if (err <= 0)
387                 return -ENOENT;
388         data->num_sensors = err;
389
390         data->sensors = kzalloc(data->num_sensors * sizeof(*data->sensors),
391                                 GFP_KERNEL);
392         if (!data->sensors)
393                 return -ENOMEM;
394
395         for (i = 0; i < data->num_sensors; i++) {
396                 err = ibmpex_query_sensor_name(data, i);
397                 if (err)
398                         continue;
399
400                 if (is_power_sensor(data->rx_msg_data, data->rx_msg_len)) {
401                         sensor_type = POWER_SENSOR;
402                         num_power++;
403                         sensor_counter = num_power;
404                         data->sensors[i].multiplier =
405                                 power_sensor_multiplier(data,
406                                                         data->rx_msg_data,
407                                                         data->rx_msg_len);
408                 } else if (is_temp_sensor(data->rx_msg_data,
409                                           data->rx_msg_len)) {
410                         sensor_type = TEMP_SENSOR;
411                         num_temp++;
412                         sensor_counter = num_temp;
413                         data->sensors[i].multiplier = 1000;
414                 } else
415                         continue;
416
417                 data->sensors[i].in_use = 1;
418
419                 /* Create attributes */
420                 for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
421                         err = create_sensor(data, sensor_type, sensor_counter,
422                                             i, j);
423                         if (err)
424                                 goto exit_remove;
425                 }
426         }
427
428         err = device_create_file(data->bmc_device,
429                         &sensor_dev_attr_reset_high_low.dev_attr);
430         if (err)
431                 goto exit_remove;
432
433         err = device_create_file(data->bmc_device,
434                         &sensor_dev_attr_name.dev_attr);
435         if (err)
436                 goto exit_remove;
437
438         return 0;
439
440 exit_remove:
441         device_remove_file(data->bmc_device,
442                            &sensor_dev_attr_reset_high_low.dev_attr);
443         device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
444         for (i = 0; i < data->num_sensors; i++)
445                 for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
446                         if (!data->sensors[i].attr[j].dev_attr.attr.name)
447                                 continue;
448                         device_remove_file(data->bmc_device,
449                                 &data->sensors[i].attr[j].dev_attr);
450                         kfree(data->sensors[i].attr[j].dev_attr.attr.name);
451                 }
452
453         kfree(data->sensors);
454         return err;
455 }
456
457 static void ibmpex_register_bmc(int iface, struct device *dev)
458 {
459         struct ibmpex_bmc_data *data;
460         int err;
461
462         data = kzalloc(sizeof(*data), GFP_KERNEL);
463         if (!data) {
464                 dev_err(dev, "Insufficient memory for BMC interface.\n");
465                 return;
466         }
467
468         data->address.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
469         data->address.channel = IPMI_BMC_CHANNEL;
470         data->address.data[0] = 0;
471         data->interface = iface;
472         data->bmc_device = dev;
473
474         /* Create IPMI messaging interface user */
475         err = ipmi_create_user(data->interface, &driver_data.ipmi_hndlrs,
476                                data, &data->user);
477         if (err < 0) {
478                 dev_err(dev, "Unable to register user with IPMI "
479                         "interface %d\n", data->interface);
480                 goto out;
481         }
482
483         mutex_init(&data->lock);
484
485         /* Initialize message */
486         data->tx_msgid = 0;
487         init_completion(&data->read_complete);
488         data->tx_message.netfn = PEX_NET_FUNCTION;
489         data->tx_message.cmd = PEX_COMMAND;
490         data->tx_message.data = data->tx_msg_data;
491
492         /* Does this BMC support PowerExecutive? */
493         err = ibmpex_ver_check(data);
494         if (err)
495                 goto out_user;
496
497         /* Register the BMC as a HWMON class device */
498         data->hwmon_dev = hwmon_device_register(data->bmc_device);
499
500         if (IS_ERR(data->hwmon_dev)) {
501                 dev_err(data->bmc_device, "Unable to register hwmon "
502                         "device for IPMI interface %d\n",
503                         data->interface);
504                 goto out_user;
505         }
506
507         /* finally add the new bmc data to the bmc data list */
508         dev_set_drvdata(dev, data);
509         list_add_tail(&data->list, &driver_data.bmc_data);
510
511         /* Now go find all the sensors */
512         err = ibmpex_find_sensors(data);
513         if (err) {
514                 dev_err(data->bmc_device, "Error %d finding sensors\n", err);
515                 goto out_register;
516         }
517
518         return;
519
520 out_register:
521         hwmon_device_unregister(data->hwmon_dev);
522 out_user:
523         ipmi_destroy_user(data->user);
524 out:
525         kfree(data);
526 }
527
528 static void ibmpex_bmc_delete(struct ibmpex_bmc_data *data)
529 {
530         int i, j;
531
532         device_remove_file(data->bmc_device,
533                            &sensor_dev_attr_reset_high_low.dev_attr);
534         device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
535         for (i = 0; i < data->num_sensors; i++)
536                 for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
537                         if (!data->sensors[i].attr[j].dev_attr.attr.name)
538                                 continue;
539                         device_remove_file(data->bmc_device,
540                                 &data->sensors[i].attr[j].dev_attr);
541                         kfree(data->sensors[i].attr[j].dev_attr.attr.name);
542                 }
543
544         list_del(&data->list);
545         dev_set_drvdata(data->bmc_device, NULL);
546         hwmon_device_unregister(data->hwmon_dev);
547         ipmi_destroy_user(data->user);
548         kfree(data->sensors);
549         kfree(data);
550 }
551
552 static void ibmpex_bmc_gone(int iface)
553 {
554         struct ibmpex_bmc_data *data = get_bmc_data(iface);
555
556         if (!data)
557                 return;
558
559         ibmpex_bmc_delete(data);
560 }
561
562 static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
563 {
564         struct ibmpex_bmc_data *data = (struct ibmpex_bmc_data *)user_msg_data;
565
566         if (msg->msgid != data->tx_msgid) {
567                 dev_err(data->bmc_device, "Mismatch between received msgid "
568                         "(%02x) and transmitted msgid (%02x)!\n",
569                         (int)msg->msgid,
570                         (int)data->tx_msgid);
571                 ipmi_free_recv_msg(msg);
572                 return;
573         }
574
575         data->rx_recv_type = msg->recv_type;
576         if (msg->msg.data_len > 0)
577                 data->rx_result = msg->msg.data[0];
578         else
579                 data->rx_result = IPMI_UNKNOWN_ERR_COMPLETION_CODE;
580
581         if (msg->msg.data_len > 1) {
582                 data->rx_msg_len = msg->msg.data_len - 1;
583                 memcpy(data->rx_msg_data, msg->msg.data + 1, data->rx_msg_len);
584         } else
585                 data->rx_msg_len = 0;
586
587         ipmi_free_recv_msg(msg);
588         complete(&data->read_complete);
589 }
590
591 static int __init ibmpex_init(void)
592 {
593         return ipmi_smi_watcher_register(&driver_data.bmc_events);
594 }
595
596 static void __exit ibmpex_exit(void)
597 {
598         struct ibmpex_bmc_data *p, *next;
599
600         ipmi_smi_watcher_unregister(&driver_data.bmc_events);
601         list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
602                 ibmpex_bmc_delete(p);
603 }
604
605 MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
606 MODULE_DESCRIPTION("IBM PowerExecutive power/temperature sensor driver");
607 MODULE_LICENSE("GPL");
608
609 module_init(ibmpex_init);
610 module_exit(ibmpex_exit);