xref: /openbmc/linux/drivers/hwmon/ibmpex.c (revision 4aea96f4)
1 /*
2  * A hwmon driver for the IBM PowerExecutive temperature/power sensors
3  * Copyright (C) 2007 IBM
4  *
5  * Author: Darrick J. Wong <darrick.wong@oracle.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 #include <linux/slab.h>
29 #include <linux/err.h>
30 
31 #define REFRESH_INTERVAL	(2 * HZ)
32 #define DRVNAME			"ibmpex"
33 
34 #define PEX_GET_VERSION		1
35 #define PEX_GET_SENSOR_COUNT	2
36 #define PEX_GET_SENSOR_NAME	3
37 #define PEX_RESET_HIGH_LOW	4
38 #define PEX_GET_SENSOR_DATA	6
39 
40 #define PEX_NET_FUNCTION	0x3A
41 #define PEX_COMMAND		0x3C
42 
43 static inline u16 extract_value(const char *data, int offset)
44 {
45 	return be16_to_cpup((__be16 *)&data[offset]);
46 }
47 
48 #define TEMP_SENSOR		1
49 #define POWER_SENSOR		2
50 
51 #define PEX_SENSOR_TYPE_LEN	3
52 static u8 const power_sensor_sig[] = {0x70, 0x77, 0x72};
53 static u8 const temp_sensor_sig[]  = {0x74, 0x65, 0x6D};
54 
55 #define PEX_MULT_LEN		2
56 static u8 const watt_sensor_sig[]  = {0x41, 0x43};
57 
58 #define PEX_NUM_SENSOR_FUNCS	3
59 static const char * const sensor_name_suffixes[] = {
60 	"",
61 	"_lowest",
62 	"_highest"
63 };
64 
65 static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
66 static void ibmpex_register_bmc(int iface, struct device *dev);
67 static void ibmpex_bmc_gone(int iface);
68 
69 struct ibmpex_sensor_data {
70 	int			in_use;
71 	s16			values[PEX_NUM_SENSOR_FUNCS];
72 	int			multiplier;
73 
74 	struct sensor_device_attribute_2	attr[PEX_NUM_SENSOR_FUNCS];
75 };
76 
77 struct ibmpex_bmc_data {
78 	struct list_head	list;
79 	struct device		*hwmon_dev;
80 	struct device		*bmc_device;
81 	struct mutex		lock;
82 	char			valid;
83 	unsigned long		last_updated;	/* In jiffies */
84 
85 	struct ipmi_addr	address;
86 	struct completion	read_complete;
87 	struct ipmi_user	*user;
88 	int			interface;
89 
90 	struct kernel_ipmi_msg	tx_message;
91 	unsigned char		tx_msg_data[IPMI_MAX_MSG_LENGTH];
92 	long			tx_msgid;
93 
94 	unsigned char		rx_msg_data[IPMI_MAX_MSG_LENGTH];
95 	unsigned long		rx_msg_len;
96 	unsigned char		rx_result;
97 	int			rx_recv_type;
98 
99 	unsigned char		sensor_major;
100 	unsigned char		sensor_minor;
101 
102 	unsigned char		num_sensors;
103 	struct ibmpex_sensor_data	*sensors;
104 };
105 
106 struct ibmpex_driver_data {
107 	struct list_head	bmc_data;
108 	struct ipmi_smi_watcher	bmc_events;
109 	struct ipmi_user_hndl	ipmi_hndlrs;
110 };
111 
112 static struct ibmpex_driver_data driver_data = {
113 	.bmc_data = LIST_HEAD_INIT(driver_data.bmc_data),
114 	.bmc_events = {
115 		.owner = THIS_MODULE,
116 		.new_smi = ibmpex_register_bmc,
117 		.smi_gone = ibmpex_bmc_gone,
118 	},
119 	.ipmi_hndlrs = {
120 		.ipmi_recv_hndl = ibmpex_msg_handler,
121 	},
122 };
123 
124 static int ibmpex_send_message(struct ibmpex_bmc_data *data)
125 {
126 	int err;
127 
128 	err = ipmi_validate_addr(&data->address, sizeof(data->address));
129 	if (err)
130 		goto out;
131 
132 	data->tx_msgid++;
133 	err = ipmi_request_settime(data->user, &data->address, data->tx_msgid,
134 				   &data->tx_message, data, 0, 0, 0);
135 	if (err)
136 		goto out1;
137 
138 	return 0;
139 out1:
140 	dev_err(data->bmc_device, "request_settime=%x\n", err);
141 	return err;
142 out:
143 	dev_err(data->bmc_device, "validate_addr=%x\n", err);
144 	return err;
145 }
146 
147 static int ibmpex_ver_check(struct ibmpex_bmc_data *data)
148 {
149 	data->tx_msg_data[0] = PEX_GET_VERSION;
150 	data->tx_message.data_len = 1;
151 	ibmpex_send_message(data);
152 
153 	wait_for_completion(&data->read_complete);
154 
155 	if (data->rx_result || data->rx_msg_len != 6)
156 		return -ENOENT;
157 
158 	data->sensor_major = data->rx_msg_data[0];
159 	data->sensor_minor = data->rx_msg_data[1];
160 
161 	dev_info(data->bmc_device,
162 		 "Found BMC with sensor interface v%d.%d %d-%02d-%02d on interface %d\n",
163 		 data->sensor_major,
164 		 data->sensor_minor,
165 		 extract_value(data->rx_msg_data, 2),
166 		 data->rx_msg_data[4],
167 		 data->rx_msg_data[5],
168 		 data->interface);
169 
170 	return 0;
171 }
172 
173 static int ibmpex_query_sensor_count(struct ibmpex_bmc_data *data)
174 {
175 	data->tx_msg_data[0] = PEX_GET_SENSOR_COUNT;
176 	data->tx_message.data_len = 1;
177 	ibmpex_send_message(data);
178 
179 	wait_for_completion(&data->read_complete);
180 
181 	if (data->rx_result || data->rx_msg_len != 1)
182 		return -ENOENT;
183 
184 	return data->rx_msg_data[0];
185 }
186 
187 static int ibmpex_query_sensor_name(struct ibmpex_bmc_data *data, int sensor)
188 {
189 	data->tx_msg_data[0] = PEX_GET_SENSOR_NAME;
190 	data->tx_msg_data[1] = sensor;
191 	data->tx_message.data_len = 2;
192 	ibmpex_send_message(data);
193 
194 	wait_for_completion(&data->read_complete);
195 
196 	if (data->rx_result || data->rx_msg_len < 1)
197 		return -ENOENT;
198 
199 	return 0;
200 }
201 
202 static int ibmpex_query_sensor_data(struct ibmpex_bmc_data *data, int sensor)
203 {
204 	data->tx_msg_data[0] = PEX_GET_SENSOR_DATA;
205 	data->tx_msg_data[1] = sensor;
206 	data->tx_message.data_len = 2;
207 	ibmpex_send_message(data);
208 
209 	wait_for_completion(&data->read_complete);
210 
211 	if (data->rx_result || data->rx_msg_len < 26) {
212 		dev_err(data->bmc_device, "Error reading sensor %d.\n",
213 			sensor);
214 		return -ENOENT;
215 	}
216 
217 	return 0;
218 }
219 
220 static int ibmpex_reset_high_low_data(struct ibmpex_bmc_data *data)
221 {
222 	data->tx_msg_data[0] = PEX_RESET_HIGH_LOW;
223 	data->tx_message.data_len = 1;
224 	ibmpex_send_message(data);
225 
226 	wait_for_completion(&data->read_complete);
227 
228 	return 0;
229 }
230 
231 static void ibmpex_update_device(struct ibmpex_bmc_data *data)
232 {
233 	int i, err;
234 
235 	mutex_lock(&data->lock);
236 	if (time_before(jiffies, data->last_updated + REFRESH_INTERVAL) &&
237 	    data->valid)
238 		goto out;
239 
240 	for (i = 0; i < data->num_sensors; i++) {
241 		if (!data->sensors[i].in_use)
242 			continue;
243 		err = ibmpex_query_sensor_data(data, i);
244 		if (err)
245 			continue;
246 		data->sensors[i].values[0] =
247 			extract_value(data->rx_msg_data, 16);
248 		data->sensors[i].values[1] =
249 			extract_value(data->rx_msg_data, 18);
250 		data->sensors[i].values[2] =
251 			extract_value(data->rx_msg_data, 20);
252 	}
253 
254 	data->last_updated = jiffies;
255 	data->valid = 1;
256 
257 out:
258 	mutex_unlock(&data->lock);
259 }
260 
261 static struct ibmpex_bmc_data *get_bmc_data(int iface)
262 {
263 	struct ibmpex_bmc_data *p, *next;
264 
265 	list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
266 		if (p->interface == iface)
267 			return p;
268 
269 	return NULL;
270 }
271 
272 static ssize_t show_name(struct device *dev, struct device_attribute *devattr,
273 			 char *buf)
274 {
275 	return sprintf(buf, "%s\n", DRVNAME);
276 }
277 static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, 0);
278 
279 static ssize_t ibmpex_show_sensor(struct device *dev,
280 				  struct device_attribute *devattr,
281 				  char *buf)
282 {
283 	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
284 	struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
285 	int mult = data->sensors[attr->index].multiplier;
286 	ibmpex_update_device(data);
287 
288 	return sprintf(buf, "%d\n",
289 		       data->sensors[attr->index].values[attr->nr] * mult);
290 }
291 
292 static ssize_t ibmpex_reset_high_low(struct device *dev,
293 				     struct device_attribute *devattr,
294 				     const char *buf,
295 				     size_t count)
296 {
297 	struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
298 
299 	ibmpex_reset_high_low_data(data);
300 
301 	return count;
302 }
303 
304 static SENSOR_DEVICE_ATTR(reset_high_low, S_IWUSR, NULL,
305 			  ibmpex_reset_high_low, 0);
306 
307 static int is_power_sensor(const char *sensor_id, int len)
308 {
309 	if (len < PEX_SENSOR_TYPE_LEN)
310 		return 0;
311 
312 	if (!memcmp(sensor_id, power_sensor_sig, PEX_SENSOR_TYPE_LEN))
313 		return 1;
314 	return 0;
315 }
316 
317 static int is_temp_sensor(const char *sensor_id, int len)
318 {
319 	if (len < PEX_SENSOR_TYPE_LEN)
320 		return 0;
321 
322 	if (!memcmp(sensor_id, temp_sensor_sig, PEX_SENSOR_TYPE_LEN))
323 		return 1;
324 	return 0;
325 }
326 
327 static int power_sensor_multiplier(struct ibmpex_bmc_data *data,
328 				   const char *sensor_id, int len)
329 {
330 	int i;
331 
332 	if (data->sensor_major == 2)
333 		return 1000000;
334 
335 	for (i = PEX_SENSOR_TYPE_LEN; i < len - 1; i++)
336 		if (!memcmp(&sensor_id[i], watt_sensor_sig, PEX_MULT_LEN))
337 			return 1000000;
338 
339 	return 100000;
340 }
341 
342 static int create_sensor(struct ibmpex_bmc_data *data, int type,
343 			 int counter, int sensor, int func)
344 {
345 	int err;
346 	char *n;
347 
348 	n = kmalloc(32, GFP_KERNEL);
349 	if (!n)
350 		return -ENOMEM;
351 
352 	if (type == TEMP_SENSOR)
353 		sprintf(n, "temp%d_input%s",
354 			counter, sensor_name_suffixes[func]);
355 	else if (type == POWER_SENSOR)
356 		sprintf(n, "power%d_average%s",
357 			counter, sensor_name_suffixes[func]);
358 
359 	sysfs_attr_init(&data->sensors[sensor].attr[func].dev_attr.attr);
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 = kcalloc(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 		return;
465 
466 	data->address.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
467 	data->address.channel = IPMI_BMC_CHANNEL;
468 	data->address.data[0] = 0;
469 	data->interface = iface;
470 	data->bmc_device = dev;
471 
472 	/* Create IPMI messaging interface user */
473 	err = ipmi_create_user(data->interface, &driver_data.ipmi_hndlrs,
474 			       data, &data->user);
475 	if (err < 0) {
476 		dev_err(dev,
477 			"Unable to register user with IPMI interface %d\n",
478 			data->interface);
479 		goto out;
480 	}
481 
482 	mutex_init(&data->lock);
483 
484 	/* Initialize message */
485 	data->tx_msgid = 0;
486 	init_completion(&data->read_complete);
487 	data->tx_message.netfn = PEX_NET_FUNCTION;
488 	data->tx_message.cmd = PEX_COMMAND;
489 	data->tx_message.data = data->tx_msg_data;
490 
491 	/* Does this BMC support PowerExecutive? */
492 	err = ibmpex_ver_check(data);
493 	if (err)
494 		goto out_user;
495 
496 	/* Register the BMC as a HWMON class device */
497 	data->hwmon_dev = hwmon_device_register(data->bmc_device);
498 
499 	if (IS_ERR(data->hwmon_dev)) {
500 		dev_err(data->bmc_device,
501 			"Unable to register hwmon device for IPMI interface %d\n",
502 			data->interface);
503 		goto out_user;
504 	}
505 
506 	/* finally add the new bmc data to the bmc data list */
507 	dev_set_drvdata(dev, data);
508 	list_add_tail(&data->list, &driver_data.bmc_data);
509 
510 	/* Now go find all the sensors */
511 	err = ibmpex_find_sensors(data);
512 	if (err) {
513 		dev_err(data->bmc_device, "Error %d finding sensors\n", err);
514 		goto out_register;
515 	}
516 
517 	return;
518 
519 out_register:
520 	hwmon_device_unregister(data->hwmon_dev);
521 out_user:
522 	ipmi_destroy_user(data->user);
523 out:
524 	kfree(data);
525 }
526 
527 static void ibmpex_bmc_delete(struct ibmpex_bmc_data *data)
528 {
529 	int i, j;
530 
531 	device_remove_file(data->bmc_device,
532 			   &sensor_dev_attr_reset_high_low.dev_attr);
533 	device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
534 	for (i = 0; i < data->num_sensors; i++)
535 		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
536 			if (!data->sensors[i].attr[j].dev_attr.attr.name)
537 				continue;
538 			device_remove_file(data->bmc_device,
539 				&data->sensors[i].attr[j].dev_attr);
540 			kfree(data->sensors[i].attr[j].dev_attr.attr.name);
541 		}
542 
543 	list_del(&data->list);
544 	dev_set_drvdata(data->bmc_device, NULL);
545 	hwmon_device_unregister(data->hwmon_dev);
546 	ipmi_destroy_user(data->user);
547 	kfree(data->sensors);
548 	kfree(data);
549 }
550 
551 static void ibmpex_bmc_gone(int iface)
552 {
553 	struct ibmpex_bmc_data *data = get_bmc_data(iface);
554 
555 	if (!data)
556 		return;
557 
558 	ibmpex_bmc_delete(data);
559 }
560 
561 static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
562 {
563 	struct ibmpex_bmc_data *data = (struct ibmpex_bmc_data *)user_msg_data;
564 
565 	if (msg->msgid != data->tx_msgid) {
566 		dev_err(data->bmc_device,
567 			"Mismatch between received msgid (%02x) and transmitted msgid (%02x)!\n",
568 			(int)msg->msgid,
569 			(int)data->tx_msgid);
570 		ipmi_free_recv_msg(msg);
571 		return;
572 	}
573 
574 	data->rx_recv_type = msg->recv_type;
575 	if (msg->msg.data_len > 0)
576 		data->rx_result = msg->msg.data[0];
577 	else
578 		data->rx_result = IPMI_UNKNOWN_ERR_COMPLETION_CODE;
579 
580 	if (msg->msg.data_len > 1) {
581 		data->rx_msg_len = msg->msg.data_len - 1;
582 		memcpy(data->rx_msg_data, msg->msg.data + 1, data->rx_msg_len);
583 	} else
584 		data->rx_msg_len = 0;
585 
586 	ipmi_free_recv_msg(msg);
587 	complete(&data->read_complete);
588 }
589 
590 static int __init ibmpex_init(void)
591 {
592 	return ipmi_smi_watcher_register(&driver_data.bmc_events);
593 }
594 
595 static void __exit ibmpex_exit(void)
596 {
597 	struct ibmpex_bmc_data *p, *next;
598 
599 	ipmi_smi_watcher_unregister(&driver_data.bmc_events);
600 	list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
601 		ibmpex_bmc_delete(p);
602 }
603 
604 MODULE_AUTHOR("Darrick J. Wong <darrick.wong@oracle.com>");
605 MODULE_DESCRIPTION("IBM PowerExecutive power/temperature sensor driver");
606 MODULE_LICENSE("GPL");
607 
608 module_init(ibmpex_init);
609 module_exit(ibmpex_exit);
610 
611 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3350-*");
612 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3550-*");
613 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3650-*");
614 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3655-*");
615 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3755-*");
616