xref: /openbmc/linux/drivers/hwmon/ibmpex.c (revision e105007c)
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((__be16 *)&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);
611 
612 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3350-*");
613 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3550-*");
614 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3650-*");
615 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3655-*");
616 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3755-*");
617