xref: /openbmc/linux/drivers/hwmon/ibmpex.c (revision 95e9fd10)
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 #include <linux/slab.h>
29 
30 #define REFRESH_INTERVAL	(2 * HZ)
31 #define DRVNAME			"ibmpex"
32 
33 #define PEX_GET_VERSION		1
34 #define PEX_GET_SENSOR_COUNT	2
35 #define PEX_GET_SENSOR_NAME	3
36 #define PEX_RESET_HIGH_LOW	4
37 #define PEX_GET_SENSOR_DATA	6
38 
39 #define PEX_NET_FUNCTION	0x3A
40 #define PEX_COMMAND		0x3C
41 
42 static inline u16 extract_value(const char *data, int offset)
43 {
44 	return be16_to_cpup((__be16 *)&data[offset]);
45 }
46 
47 #define TEMP_SENSOR		1
48 #define POWER_SENSOR		2
49 
50 #define PEX_SENSOR_TYPE_LEN	3
51 static u8 const power_sensor_sig[] = {0x70, 0x77, 0x72};
52 static u8 const temp_sensor_sig[]  = {0x74, 0x65, 0x6D};
53 
54 #define PEX_MULT_LEN		2
55 static u8 const watt_sensor_sig[]  = {0x41, 0x43};
56 
57 #define PEX_NUM_SENSOR_FUNCS	3
58 static char const * const power_sensor_name_templates[] = {
59 	"%s%d_average",
60 	"%s%d_average_lowest",
61 	"%s%d_average_highest"
62 };
63 static char const * const temp_sensor_name_templates[] = {
64 	"%s%d_input",
65 	"%s%d_input_lowest",
66 	"%s%d_input_highest"
67 };
68 
69 static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
70 static void ibmpex_register_bmc(int iface, struct device *dev);
71 static void ibmpex_bmc_gone(int iface);
72 
73 struct ibmpex_sensor_data {
74 	int			in_use;
75 	s16			values[PEX_NUM_SENSOR_FUNCS];
76 	int			multiplier;
77 
78 	struct sensor_device_attribute_2	attr[PEX_NUM_SENSOR_FUNCS];
79 };
80 
81 struct ibmpex_bmc_data {
82 	struct list_head	list;
83 	struct device		*hwmon_dev;
84 	struct device		*bmc_device;
85 	struct mutex		lock;
86 	char			valid;
87 	unsigned long		last_updated;	/* In jiffies */
88 
89 	struct ipmi_addr	address;
90 	struct completion	read_complete;
91 	ipmi_user_t		user;
92 	int			interface;
93 
94 	struct kernel_ipmi_msg	tx_message;
95 	unsigned char		tx_msg_data[IPMI_MAX_MSG_LENGTH];
96 	long			tx_msgid;
97 
98 	unsigned char		rx_msg_data[IPMI_MAX_MSG_LENGTH];
99 	unsigned long		rx_msg_len;
100 	unsigned char		rx_result;
101 	int			rx_recv_type;
102 
103 	unsigned char		sensor_major;
104 	unsigned char		sensor_minor;
105 
106 	unsigned char		num_sensors;
107 	struct ibmpex_sensor_data	*sensors;
108 };
109 
110 struct ibmpex_driver_data {
111 	struct list_head	bmc_data;
112 	struct ipmi_smi_watcher	bmc_events;
113 	struct ipmi_user_hndl	ipmi_hndlrs;
114 };
115 
116 static struct ibmpex_driver_data driver_data = {
117 	.bmc_data = LIST_HEAD_INIT(driver_data.bmc_data),
118 	.bmc_events = {
119 		.owner = THIS_MODULE,
120 		.new_smi = ibmpex_register_bmc,
121 		.smi_gone = ibmpex_bmc_gone,
122 	},
123 	.ipmi_hndlrs = {
124 		.ipmi_recv_hndl = ibmpex_msg_handler,
125 	},
126 };
127 
128 static int ibmpex_send_message(struct ibmpex_bmc_data *data)
129 {
130 	int err;
131 
132 	err = ipmi_validate_addr(&data->address, sizeof(data->address));
133 	if (err)
134 		goto out;
135 
136 	data->tx_msgid++;
137 	err = ipmi_request_settime(data->user, &data->address, data->tx_msgid,
138 				   &data->tx_message, data, 0, 0, 0);
139 	if (err)
140 		goto out1;
141 
142 	return 0;
143 out1:
144 	dev_err(data->bmc_device, "request_settime=%x\n", err);
145 	return err;
146 out:
147 	dev_err(data->bmc_device, "validate_addr=%x\n", err);
148 	return err;
149 }
150 
151 static int ibmpex_ver_check(struct ibmpex_bmc_data *data)
152 {
153 	data->tx_msg_data[0] = PEX_GET_VERSION;
154 	data->tx_message.data_len = 1;
155 	ibmpex_send_message(data);
156 
157 	wait_for_completion(&data->read_complete);
158 
159 	if (data->rx_result || data->rx_msg_len != 6)
160 		return -ENOENT;
161 
162 	data->sensor_major = data->rx_msg_data[0];
163 	data->sensor_minor = data->rx_msg_data[1];
164 
165 	dev_info(data->bmc_device, "Found BMC with sensor interface "
166 		 "v%d.%d %d-%02d-%02d on interface %d\n",
167 		 data->sensor_major,
168 		 data->sensor_minor,
169 		 extract_value(data->rx_msg_data, 2),
170 		 data->rx_msg_data[4],
171 		 data->rx_msg_data[5],
172 		 data->interface);
173 
174 	return 0;
175 }
176 
177 static int ibmpex_query_sensor_count(struct ibmpex_bmc_data *data)
178 {
179 	data->tx_msg_data[0] = PEX_GET_SENSOR_COUNT;
180 	data->tx_message.data_len = 1;
181 	ibmpex_send_message(data);
182 
183 	wait_for_completion(&data->read_complete);
184 
185 	if (data->rx_result || data->rx_msg_len != 1)
186 		return -ENOENT;
187 
188 	return data->rx_msg_data[0];
189 }
190 
191 static int ibmpex_query_sensor_name(struct ibmpex_bmc_data *data, int sensor)
192 {
193 	data->tx_msg_data[0] = PEX_GET_SENSOR_NAME;
194 	data->tx_msg_data[1] = sensor;
195 	data->tx_message.data_len = 2;
196 	ibmpex_send_message(data);
197 
198 	wait_for_completion(&data->read_complete);
199 
200 	if (data->rx_result || data->rx_msg_len < 1)
201 		return -ENOENT;
202 
203 	return 0;
204 }
205 
206 static int ibmpex_query_sensor_data(struct ibmpex_bmc_data *data, int sensor)
207 {
208 	data->tx_msg_data[0] = PEX_GET_SENSOR_DATA;
209 	data->tx_msg_data[1] = sensor;
210 	data->tx_message.data_len = 2;
211 	ibmpex_send_message(data);
212 
213 	wait_for_completion(&data->read_complete);
214 
215 	if (data->rx_result || data->rx_msg_len < 26) {
216 		dev_err(data->bmc_device, "Error reading sensor %d.\n",
217 			sensor);
218 		return -ENOENT;
219 	}
220 
221 	return 0;
222 }
223 
224 static int ibmpex_reset_high_low_data(struct ibmpex_bmc_data *data)
225 {
226 	data->tx_msg_data[0] = PEX_RESET_HIGH_LOW;
227 	data->tx_message.data_len = 1;
228 	ibmpex_send_message(data);
229 
230 	wait_for_completion(&data->read_complete);
231 
232 	return 0;
233 }
234 
235 static void ibmpex_update_device(struct ibmpex_bmc_data *data)
236 {
237 	int i, err;
238 
239 	mutex_lock(&data->lock);
240 	if (time_before(jiffies, data->last_updated + REFRESH_INTERVAL) &&
241 	    data->valid)
242 		goto out;
243 
244 	for (i = 0; i < data->num_sensors; i++) {
245 		if (!data->sensors[i].in_use)
246 			continue;
247 		err = ibmpex_query_sensor_data(data, i);
248 		if (err)
249 			continue;
250 		data->sensors[i].values[0] =
251 			extract_value(data->rx_msg_data, 16);
252 		data->sensors[i].values[1] =
253 			extract_value(data->rx_msg_data, 18);
254 		data->sensors[i].values[2] =
255 			extract_value(data->rx_msg_data, 20);
256 	}
257 
258 	data->last_updated = jiffies;
259 	data->valid = 1;
260 
261 out:
262 	mutex_unlock(&data->lock);
263 }
264 
265 static struct ibmpex_bmc_data *get_bmc_data(int iface)
266 {
267 	struct ibmpex_bmc_data *p, *next;
268 
269 	list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
270 		if (p->interface == iface)
271 			return p;
272 
273 	return NULL;
274 }
275 
276 static ssize_t show_name(struct device *dev, struct device_attribute *devattr,
277 			 char *buf)
278 {
279 	return sprintf(buf, "%s\n", DRVNAME);
280 }
281 static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, 0);
282 
283 static ssize_t ibmpex_show_sensor(struct device *dev,
284 				  struct device_attribute *devattr,
285 				  char *buf)
286 {
287 	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
288 	struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
289 	int mult = data->sensors[attr->index].multiplier;
290 	ibmpex_update_device(data);
291 
292 	return sprintf(buf, "%d\n",
293 		       data->sensors[attr->index].values[attr->nr] * mult);
294 }
295 
296 static ssize_t ibmpex_reset_high_low(struct device *dev,
297 				     struct device_attribute *devattr,
298 				     const char *buf,
299 				     size_t count)
300 {
301 	struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
302 
303 	ibmpex_reset_high_low_data(data);
304 
305 	return count;
306 }
307 
308 static SENSOR_DEVICE_ATTR(reset_high_low, S_IWUSR, NULL,
309 			  ibmpex_reset_high_low, 0);
310 
311 static int is_power_sensor(const char *sensor_id, int len)
312 {
313 	if (len < PEX_SENSOR_TYPE_LEN)
314 		return 0;
315 
316 	if (!memcmp(sensor_id, power_sensor_sig, PEX_SENSOR_TYPE_LEN))
317 		return 1;
318 	return 0;
319 }
320 
321 static int is_temp_sensor(const char *sensor_id, int len)
322 {
323 	if (len < PEX_SENSOR_TYPE_LEN)
324 		return 0;
325 
326 	if (!memcmp(sensor_id, temp_sensor_sig, PEX_SENSOR_TYPE_LEN))
327 		return 1;
328 	return 0;
329 }
330 
331 static int power_sensor_multiplier(struct ibmpex_bmc_data *data,
332 				   const char *sensor_id, int len)
333 {
334 	int i;
335 
336 	if (data->sensor_major == 2)
337 		return 1000000;
338 
339 	for (i = PEX_SENSOR_TYPE_LEN; i < len - 1; i++)
340 		if (!memcmp(&sensor_id[i], watt_sensor_sig, PEX_MULT_LEN))
341 			return 1000000;
342 
343 	return 100000;
344 }
345 
346 static int create_sensor(struct ibmpex_bmc_data *data, int type,
347 			 int counter, int sensor, int func)
348 {
349 	int err;
350 	char *n;
351 
352 	n = kmalloc(32, GFP_KERNEL);
353 	if (!n)
354 		return -ENOMEM;
355 
356 	if (type == TEMP_SENSOR)
357 		sprintf(n, temp_sensor_name_templates[func], "temp", counter);
358 	else if (type == POWER_SENSOR)
359 		sprintf(n, power_sensor_name_templates[func], "power", counter);
360 
361 	sysfs_attr_init(&data->sensors[sensor].attr[func].dev_attr.attr);
362 	data->sensors[sensor].attr[func].dev_attr.attr.name = n;
363 	data->sensors[sensor].attr[func].dev_attr.attr.mode = S_IRUGO;
364 	data->sensors[sensor].attr[func].dev_attr.show = ibmpex_show_sensor;
365 	data->sensors[sensor].attr[func].index = sensor;
366 	data->sensors[sensor].attr[func].nr = func;
367 
368 	err = device_create_file(data->bmc_device,
369 				 &data->sensors[sensor].attr[func].dev_attr);
370 	if (err) {
371 		data->sensors[sensor].attr[func].dev_attr.attr.name = NULL;
372 		kfree(n);
373 		return err;
374 	}
375 
376 	return 0;
377 }
378 
379 static int ibmpex_find_sensors(struct ibmpex_bmc_data *data)
380 {
381 	int i, j, err;
382 	int sensor_type;
383 	int sensor_counter;
384 	int num_power = 0;
385 	int num_temp = 0;
386 
387 	err = ibmpex_query_sensor_count(data);
388 	if (err <= 0)
389 		return -ENOENT;
390 	data->num_sensors = err;
391 
392 	data->sensors = kzalloc(data->num_sensors * sizeof(*data->sensors),
393 				GFP_KERNEL);
394 	if (!data->sensors)
395 		return -ENOMEM;
396 
397 	for (i = 0; i < data->num_sensors; i++) {
398 		err = ibmpex_query_sensor_name(data, i);
399 		if (err)
400 			continue;
401 
402 		if (is_power_sensor(data->rx_msg_data, data->rx_msg_len)) {
403 			sensor_type = POWER_SENSOR;
404 			num_power++;
405 			sensor_counter = num_power;
406 			data->sensors[i].multiplier =
407 				power_sensor_multiplier(data,
408 							data->rx_msg_data,
409 							data->rx_msg_len);
410 		} else if (is_temp_sensor(data->rx_msg_data,
411 					  data->rx_msg_len)) {
412 			sensor_type = TEMP_SENSOR;
413 			num_temp++;
414 			sensor_counter = num_temp;
415 			data->sensors[i].multiplier = 1000;
416 		} else
417 			continue;
418 
419 		data->sensors[i].in_use = 1;
420 
421 		/* Create attributes */
422 		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
423 			err = create_sensor(data, sensor_type, sensor_counter,
424 					    i, j);
425 			if (err)
426 				goto exit_remove;
427 		}
428 	}
429 
430 	err = device_create_file(data->bmc_device,
431 			&sensor_dev_attr_reset_high_low.dev_attr);
432 	if (err)
433 		goto exit_remove;
434 
435 	err = device_create_file(data->bmc_device,
436 			&sensor_dev_attr_name.dev_attr);
437 	if (err)
438 		goto exit_remove;
439 
440 	return 0;
441 
442 exit_remove:
443 	device_remove_file(data->bmc_device,
444 			   &sensor_dev_attr_reset_high_low.dev_attr);
445 	device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
446 	for (i = 0; i < data->num_sensors; i++)
447 		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
448 			if (!data->sensors[i].attr[j].dev_attr.attr.name)
449 				continue;
450 			device_remove_file(data->bmc_device,
451 				&data->sensors[i].attr[j].dev_attr);
452 			kfree(data->sensors[i].attr[j].dev_attr.attr.name);
453 		}
454 
455 	kfree(data->sensors);
456 	return err;
457 }
458 
459 static void ibmpex_register_bmc(int iface, struct device *dev)
460 {
461 	struct ibmpex_bmc_data *data;
462 	int err;
463 
464 	data = kzalloc(sizeof(*data), GFP_KERNEL);
465 	if (!data) {
466 		dev_err(dev, "Insufficient memory for BMC interface.\n");
467 		return;
468 	}
469 
470 	data->address.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
471 	data->address.channel = IPMI_BMC_CHANNEL;
472 	data->address.data[0] = 0;
473 	data->interface = iface;
474 	data->bmc_device = dev;
475 
476 	/* Create IPMI messaging interface user */
477 	err = ipmi_create_user(data->interface, &driver_data.ipmi_hndlrs,
478 			       data, &data->user);
479 	if (err < 0) {
480 		dev_err(dev, "Unable to register user with IPMI "
481 			"interface %d\n", data->interface);
482 		goto out;
483 	}
484 
485 	mutex_init(&data->lock);
486 
487 	/* Initialize message */
488 	data->tx_msgid = 0;
489 	init_completion(&data->read_complete);
490 	data->tx_message.netfn = PEX_NET_FUNCTION;
491 	data->tx_message.cmd = PEX_COMMAND;
492 	data->tx_message.data = data->tx_msg_data;
493 
494 	/* Does this BMC support PowerExecutive? */
495 	err = ibmpex_ver_check(data);
496 	if (err)
497 		goto out_user;
498 
499 	/* Register the BMC as a HWMON class device */
500 	data->hwmon_dev = hwmon_device_register(data->bmc_device);
501 
502 	if (IS_ERR(data->hwmon_dev)) {
503 		dev_err(data->bmc_device, "Unable to register hwmon "
504 			"device for IPMI interface %d\n",
505 			data->interface);
506 		goto out_user;
507 	}
508 
509 	/* finally add the new bmc data to the bmc data list */
510 	dev_set_drvdata(dev, data);
511 	list_add_tail(&data->list, &driver_data.bmc_data);
512 
513 	/* Now go find all the sensors */
514 	err = ibmpex_find_sensors(data);
515 	if (err) {
516 		dev_err(data->bmc_device, "Error %d finding sensors\n", err);
517 		goto out_register;
518 	}
519 
520 	return;
521 
522 out_register:
523 	hwmon_device_unregister(data->hwmon_dev);
524 out_user:
525 	ipmi_destroy_user(data->user);
526 out:
527 	kfree(data);
528 }
529 
530 static void ibmpex_bmc_delete(struct ibmpex_bmc_data *data)
531 {
532 	int i, j;
533 
534 	device_remove_file(data->bmc_device,
535 			   &sensor_dev_attr_reset_high_low.dev_attr);
536 	device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
537 	for (i = 0; i < data->num_sensors; i++)
538 		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
539 			if (!data->sensors[i].attr[j].dev_attr.attr.name)
540 				continue;
541 			device_remove_file(data->bmc_device,
542 				&data->sensors[i].attr[j].dev_attr);
543 			kfree(data->sensors[i].attr[j].dev_attr.attr.name);
544 		}
545 
546 	list_del(&data->list);
547 	dev_set_drvdata(data->bmc_device, NULL);
548 	hwmon_device_unregister(data->hwmon_dev);
549 	ipmi_destroy_user(data->user);
550 	kfree(data->sensors);
551 	kfree(data);
552 }
553 
554 static void ibmpex_bmc_gone(int iface)
555 {
556 	struct ibmpex_bmc_data *data = get_bmc_data(iface);
557 
558 	if (!data)
559 		return;
560 
561 	ibmpex_bmc_delete(data);
562 }
563 
564 static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
565 {
566 	struct ibmpex_bmc_data *data = (struct ibmpex_bmc_data *)user_msg_data;
567 
568 	if (msg->msgid != data->tx_msgid) {
569 		dev_err(data->bmc_device, "Mismatch between received msgid "
570 			"(%02x) and transmitted msgid (%02x)!\n",
571 			(int)msg->msgid,
572 			(int)data->tx_msgid);
573 		ipmi_free_recv_msg(msg);
574 		return;
575 	}
576 
577 	data->rx_recv_type = msg->recv_type;
578 	if (msg->msg.data_len > 0)
579 		data->rx_result = msg->msg.data[0];
580 	else
581 		data->rx_result = IPMI_UNKNOWN_ERR_COMPLETION_CODE;
582 
583 	if (msg->msg.data_len > 1) {
584 		data->rx_msg_len = msg->msg.data_len - 1;
585 		memcpy(data->rx_msg_data, msg->msg.data + 1, data->rx_msg_len);
586 	} else
587 		data->rx_msg_len = 0;
588 
589 	ipmi_free_recv_msg(msg);
590 	complete(&data->read_complete);
591 }
592 
593 static int __init ibmpex_init(void)
594 {
595 	return ipmi_smi_watcher_register(&driver_data.bmc_events);
596 }
597 
598 static void __exit ibmpex_exit(void)
599 {
600 	struct ibmpex_bmc_data *p, *next;
601 
602 	ipmi_smi_watcher_unregister(&driver_data.bmc_events);
603 	list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
604 		ibmpex_bmc_delete(p);
605 }
606 
607 MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
608 MODULE_DESCRIPTION("IBM PowerExecutive power/temperature sensor driver");
609 MODULE_LICENSE("GPL");
610 
611 module_init(ibmpex_init);
612 module_exit(ibmpex_exit);
613 
614 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3350-*");
615 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3550-*");
616 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3650-*");
617 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3655-*");
618 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3755-*");
619