1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * A hwmon driver for the IBM PowerExecutive temperature/power sensors
4 * Copyright (C) 2007 IBM
5 *
6 * Author: Darrick J. Wong <darrick.wong@oracle.com>
7 */
8
9#include <linux/ipmi.h>
10#include <linux/module.h>
11#include <linux/hwmon.h>
12#include <linux/hwmon-sysfs.h>
13#include <linux/jiffies.h>
14#include <linux/mutex.h>
15#include <linux/slab.h>
16#include <linux/err.h>
17
18#define REFRESH_INTERVAL	(2 * HZ)
19#define DRVNAME			"ibmpex"
20
21#define PEX_GET_VERSION		1
22#define PEX_GET_SENSOR_COUNT	2
23#define PEX_GET_SENSOR_NAME	3
24#define PEX_RESET_HIGH_LOW	4
25#define PEX_GET_SENSOR_DATA	6
26
27#define PEX_NET_FUNCTION	0x3A
28#define PEX_COMMAND		0x3C
29
30static inline u16 extract_value(const char *data, int offset)
31{
32	return be16_to_cpup((__be16 *)&data[offset]);
33}
34
35#define TEMP_SENSOR		1
36#define POWER_SENSOR		2
37
38#define PEX_SENSOR_TYPE_LEN	3
39static u8 const power_sensor_sig[] = {0x70, 0x77, 0x72};
40static u8 const temp_sensor_sig[]  = {0x74, 0x65, 0x6D};
41
42#define PEX_MULT_LEN		2
43static u8 const watt_sensor_sig[]  = {0x41, 0x43};
44
45#define PEX_NUM_SENSOR_FUNCS	3
46static const char * const sensor_name_suffixes[] = {
47	"",
48	"_lowest",
49	"_highest"
50};
51
52static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
53static void ibmpex_register_bmc(int iface, struct device *dev);
54static void ibmpex_bmc_gone(int iface);
55
56struct ibmpex_sensor_data {
57	int			in_use;
58	s16			values[PEX_NUM_SENSOR_FUNCS];
59	int			multiplier;
60
61	struct sensor_device_attribute_2	attr[PEX_NUM_SENSOR_FUNCS];
62};
63
64struct ibmpex_bmc_data {
65	struct list_head	list;
66	struct device		*hwmon_dev;
67	struct device		*bmc_device;
68	struct mutex		lock;
69	bool			valid;
70	unsigned long		last_updated;	/* In jiffies */
71
72	struct ipmi_addr	address;
73	struct completion	read_complete;
74	struct ipmi_user	*user;
75	int			interface;
76
77	struct kernel_ipmi_msg	tx_message;
78	unsigned char		tx_msg_data[IPMI_MAX_MSG_LENGTH];
79	long			tx_msgid;
80
81	unsigned char		rx_msg_data[IPMI_MAX_MSG_LENGTH];
82	unsigned long		rx_msg_len;
83	unsigned char		rx_result;
84	int			rx_recv_type;
85
86	unsigned char		sensor_major;
87	unsigned char		sensor_minor;
88
89	unsigned char		num_sensors;
90	struct ibmpex_sensor_data	*sensors;
91};
92
93struct ibmpex_driver_data {
94	struct list_head	bmc_data;
95	struct ipmi_smi_watcher	bmc_events;
96	struct ipmi_user_hndl	ipmi_hndlrs;
97};
98
99static struct ibmpex_driver_data driver_data = {
100	.bmc_data = LIST_HEAD_INIT(driver_data.bmc_data),
101	.bmc_events = {
102		.owner = THIS_MODULE,
103		.new_smi = ibmpex_register_bmc,
104		.smi_gone = ibmpex_bmc_gone,
105	},
106	.ipmi_hndlrs = {
107		.ipmi_recv_hndl = ibmpex_msg_handler,
108	},
109};
110
111static int ibmpex_send_message(struct ibmpex_bmc_data *data)
112{
113	int err;
114
115	err = ipmi_validate_addr(&data->address, sizeof(data->address));
116	if (err)
117		goto out;
118
119	data->tx_msgid++;
120	err = ipmi_request_settime(data->user, &data->address, data->tx_msgid,
121				   &data->tx_message, data, 0, 0, 0);
122	if (err)
123		goto out1;
124
125	return 0;
126out1:
127	dev_err(data->bmc_device, "request_settime=%x\n", err);
128	return err;
129out:
130	dev_err(data->bmc_device, "validate_addr=%x\n", err);
131	return err;
132}
133
134static int ibmpex_ver_check(struct ibmpex_bmc_data *data)
135{
136	data->tx_msg_data[0] = PEX_GET_VERSION;
137	data->tx_message.data_len = 1;
138	ibmpex_send_message(data);
139
140	wait_for_completion(&data->read_complete);
141
142	if (data->rx_result || data->rx_msg_len != 6)
143		return -ENOENT;
144
145	data->sensor_major = data->rx_msg_data[0];
146	data->sensor_minor = data->rx_msg_data[1];
147
148	dev_info(data->bmc_device,
149		 "Found BMC with sensor interface v%d.%d %d-%02d-%02d on interface %d\n",
150		 data->sensor_major,
151		 data->sensor_minor,
152		 extract_value(data->rx_msg_data, 2),
153		 data->rx_msg_data[4],
154		 data->rx_msg_data[5],
155		 data->interface);
156
157	return 0;
158}
159
160static int ibmpex_query_sensor_count(struct ibmpex_bmc_data *data)
161{
162	data->tx_msg_data[0] = PEX_GET_SENSOR_COUNT;
163	data->tx_message.data_len = 1;
164	ibmpex_send_message(data);
165
166	wait_for_completion(&data->read_complete);
167
168	if (data->rx_result || data->rx_msg_len != 1)
169		return -ENOENT;
170
171	return data->rx_msg_data[0];
172}
173
174static int ibmpex_query_sensor_name(struct ibmpex_bmc_data *data, int sensor)
175{
176	data->tx_msg_data[0] = PEX_GET_SENSOR_NAME;
177	data->tx_msg_data[1] = sensor;
178	data->tx_message.data_len = 2;
179	ibmpex_send_message(data);
180
181	wait_for_completion(&data->read_complete);
182
183	if (data->rx_result || data->rx_msg_len < 1)
184		return -ENOENT;
185
186	return 0;
187}
188
189static int ibmpex_query_sensor_data(struct ibmpex_bmc_data *data, int sensor)
190{
191	data->tx_msg_data[0] = PEX_GET_SENSOR_DATA;
192	data->tx_msg_data[1] = sensor;
193	data->tx_message.data_len = 2;
194	ibmpex_send_message(data);
195
196	wait_for_completion(&data->read_complete);
197
198	if (data->rx_result || data->rx_msg_len < 26) {
199		dev_err(data->bmc_device, "Error reading sensor %d.\n",
200			sensor);
201		return -ENOENT;
202	}
203
204	return 0;
205}
206
207static int ibmpex_reset_high_low_data(struct ibmpex_bmc_data *data)
208{
209	data->tx_msg_data[0] = PEX_RESET_HIGH_LOW;
210	data->tx_message.data_len = 1;
211	ibmpex_send_message(data);
212
213	wait_for_completion(&data->read_complete);
214
215	return 0;
216}
217
218static void ibmpex_update_device(struct ibmpex_bmc_data *data)
219{
220	int i, err;
221
222	mutex_lock(&data->lock);
223	if (time_before(jiffies, data->last_updated + REFRESH_INTERVAL) &&
224	    data->valid)
225		goto out;
226
227	for (i = 0; i < data->num_sensors; i++) {
228		if (!data->sensors[i].in_use)
229			continue;
230		err = ibmpex_query_sensor_data(data, i);
231		if (err)
232			continue;
233		data->sensors[i].values[0] =
234			extract_value(data->rx_msg_data, 16);
235		data->sensors[i].values[1] =
236			extract_value(data->rx_msg_data, 18);
237		data->sensors[i].values[2] =
238			extract_value(data->rx_msg_data, 20);
239	}
240
241	data->last_updated = jiffies;
242	data->valid = true;
243
244out:
245	mutex_unlock(&data->lock);
246}
247
248static struct ibmpex_bmc_data *get_bmc_data(int iface)
249{
250	struct ibmpex_bmc_data *p, *next;
251
252	list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
253		if (p->interface == iface)
254			return p;
255
256	return NULL;
257}
258
259static ssize_t name_show(struct device *dev, struct device_attribute *devattr,
260			 char *buf)
261{
262	return sprintf(buf, "%s\n", DRVNAME);
263}
264static SENSOR_DEVICE_ATTR_RO(name, name, 0);
265
266static ssize_t ibmpex_show_sensor(struct device *dev,
267				  struct device_attribute *devattr,
268				  char *buf)
269{
270	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
271	struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
272	int mult = data->sensors[attr->index].multiplier;
273	ibmpex_update_device(data);
274
275	return sprintf(buf, "%d\n",
276		       data->sensors[attr->index].values[attr->nr] * mult);
277}
278
279static ssize_t ibmpex_high_low_store(struct device *dev,
280				     struct device_attribute *devattr,
281				     const char *buf, size_t count)
282{
283	struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
284
285	ibmpex_reset_high_low_data(data);
286
287	return count;
288}
289
290static SENSOR_DEVICE_ATTR_WO(reset_high_low, ibmpex_high_low, 0);
291
292static int is_power_sensor(const char *sensor_id, int len)
293{
294	if (len < PEX_SENSOR_TYPE_LEN)
295		return 0;
296
297	if (!memcmp(sensor_id, power_sensor_sig, PEX_SENSOR_TYPE_LEN))
298		return 1;
299	return 0;
300}
301
302static int is_temp_sensor(const char *sensor_id, int len)
303{
304	if (len < PEX_SENSOR_TYPE_LEN)
305		return 0;
306
307	if (!memcmp(sensor_id, temp_sensor_sig, PEX_SENSOR_TYPE_LEN))
308		return 1;
309	return 0;
310}
311
312static int power_sensor_multiplier(struct ibmpex_bmc_data *data,
313				   const char *sensor_id, int len)
314{
315	int i;
316
317	if (data->sensor_major == 2)
318		return 1000000;
319
320	for (i = PEX_SENSOR_TYPE_LEN; i < len - 1; i++)
321		if (!memcmp(&sensor_id[i], watt_sensor_sig, PEX_MULT_LEN))
322			return 1000000;
323
324	return 100000;
325}
326
327static int create_sensor(struct ibmpex_bmc_data *data, int type,
328			 int counter, int sensor, int func)
329{
330	int err;
331	char *n;
332
333	n = kmalloc(32, GFP_KERNEL);
334	if (!n)
335		return -ENOMEM;
336
337	if (type == TEMP_SENSOR)
338		sprintf(n, "temp%d_input%s",
339			counter, sensor_name_suffixes[func]);
340	else if (type == POWER_SENSOR)
341		sprintf(n, "power%d_average%s",
342			counter, sensor_name_suffixes[func]);
343
344	sysfs_attr_init(&data->sensors[sensor].attr[func].dev_attr.attr);
345	data->sensors[sensor].attr[func].dev_attr.attr.name = n;
346	data->sensors[sensor].attr[func].dev_attr.attr.mode = 0444;
347	data->sensors[sensor].attr[func].dev_attr.show = ibmpex_show_sensor;
348	data->sensors[sensor].attr[func].index = sensor;
349	data->sensors[sensor].attr[func].nr = func;
350
351	err = device_create_file(data->bmc_device,
352				 &data->sensors[sensor].attr[func].dev_attr);
353	if (err) {
354		data->sensors[sensor].attr[func].dev_attr.attr.name = NULL;
355		kfree(n);
356		return err;
357	}
358
359	return 0;
360}
361
362static int ibmpex_find_sensors(struct ibmpex_bmc_data *data)
363{
364	int i, j, err;
365	int sensor_type;
366	int sensor_counter;
367	int num_power = 0;
368	int num_temp = 0;
369
370	err = ibmpex_query_sensor_count(data);
371	if (err <= 0)
372		return -ENOENT;
373	data->num_sensors = err;
374
375	data->sensors = kcalloc(data->num_sensors, sizeof(*data->sensors),
376				GFP_KERNEL);
377	if (!data->sensors)
378		return -ENOMEM;
379
380	for (i = 0; i < data->num_sensors; i++) {
381		err = ibmpex_query_sensor_name(data, i);
382		if (err)
383			continue;
384
385		if (is_power_sensor(data->rx_msg_data, data->rx_msg_len)) {
386			sensor_type = POWER_SENSOR;
387			num_power++;
388			sensor_counter = num_power;
389			data->sensors[i].multiplier =
390				power_sensor_multiplier(data,
391							data->rx_msg_data,
392							data->rx_msg_len);
393		} else if (is_temp_sensor(data->rx_msg_data,
394					  data->rx_msg_len)) {
395			sensor_type = TEMP_SENSOR;
396			num_temp++;
397			sensor_counter = num_temp;
398			data->sensors[i].multiplier = 1000;
399		} else
400			continue;
401
402		data->sensors[i].in_use = 1;
403
404		/* Create attributes */
405		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
406			err = create_sensor(data, sensor_type, sensor_counter,
407					    i, j);
408			if (err)
409				goto exit_remove;
410		}
411	}
412
413	err = device_create_file(data->bmc_device,
414			&sensor_dev_attr_reset_high_low.dev_attr);
415	if (err)
416		goto exit_remove;
417
418	err = device_create_file(data->bmc_device,
419			&sensor_dev_attr_name.dev_attr);
420	if (err)
421		goto exit_remove;
422
423	return 0;
424
425exit_remove:
426	device_remove_file(data->bmc_device,
427			   &sensor_dev_attr_reset_high_low.dev_attr);
428	device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
429	for (i = 0; i < data->num_sensors; i++)
430		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
431			if (!data->sensors[i].attr[j].dev_attr.attr.name)
432				continue;
433			device_remove_file(data->bmc_device,
434				&data->sensors[i].attr[j].dev_attr);
435			kfree(data->sensors[i].attr[j].dev_attr.attr.name);
436		}
437
438	kfree(data->sensors);
439	return err;
440}
441
442static void ibmpex_register_bmc(int iface, struct device *dev)
443{
444	struct ibmpex_bmc_data *data;
445	int err;
446
447	data = kzalloc(sizeof(*data), GFP_KERNEL);
448	if (!data)
449		return;
450
451	data->address.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
452	data->address.channel = IPMI_BMC_CHANNEL;
453	data->address.data[0] = 0;
454	data->interface = iface;
455	data->bmc_device = dev;
456
457	/* Create IPMI messaging interface user */
458	err = ipmi_create_user(data->interface, &driver_data.ipmi_hndlrs,
459			       data, &data->user);
460	if (err < 0) {
461		dev_err(dev,
462			"Unable to register user with IPMI interface %d\n",
463			data->interface);
464		goto out;
465	}
466
467	mutex_init(&data->lock);
468
469	/* Initialize message */
470	data->tx_msgid = 0;
471	init_completion(&data->read_complete);
472	data->tx_message.netfn = PEX_NET_FUNCTION;
473	data->tx_message.cmd = PEX_COMMAND;
474	data->tx_message.data = data->tx_msg_data;
475
476	/* Does this BMC support PowerExecutive? */
477	err = ibmpex_ver_check(data);
478	if (err)
479		goto out_user;
480
481	/* Register the BMC as a HWMON class device */
482	data->hwmon_dev = hwmon_device_register(data->bmc_device);
483
484	if (IS_ERR(data->hwmon_dev)) {
485		dev_err(data->bmc_device,
486			"Unable to register hwmon device for IPMI interface %d\n",
487			data->interface);
488		goto out_user;
489	}
490
491	/* finally add the new bmc data to the bmc data list */
492	dev_set_drvdata(dev, data);
493	list_add_tail(&data->list, &driver_data.bmc_data);
494
495	/* Now go find all the sensors */
496	err = ibmpex_find_sensors(data);
497	if (err) {
498		dev_err(data->bmc_device, "Error %d finding sensors\n", err);
499		goto out_register;
500	}
501
502	return;
503
504out_register:
505	list_del(&data->list);
506	hwmon_device_unregister(data->hwmon_dev);
507out_user:
508	ipmi_destroy_user(data->user);
509out:
510	kfree(data);
511}
512
513static void ibmpex_bmc_delete(struct ibmpex_bmc_data *data)
514{
515	int i, j;
516
517	device_remove_file(data->bmc_device,
518			   &sensor_dev_attr_reset_high_low.dev_attr);
519	device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
520	for (i = 0; i < data->num_sensors; i++)
521		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
522			if (!data->sensors[i].attr[j].dev_attr.attr.name)
523				continue;
524			device_remove_file(data->bmc_device,
525				&data->sensors[i].attr[j].dev_attr);
526			kfree(data->sensors[i].attr[j].dev_attr.attr.name);
527		}
528
529	list_del(&data->list);
530	dev_set_drvdata(data->bmc_device, NULL);
531	hwmon_device_unregister(data->hwmon_dev);
532	ipmi_destroy_user(data->user);
533	kfree(data->sensors);
534	kfree(data);
535}
536
537static void ibmpex_bmc_gone(int iface)
538{
539	struct ibmpex_bmc_data *data = get_bmc_data(iface);
540
541	if (!data)
542		return;
543
544	ibmpex_bmc_delete(data);
545}
546
547static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
548{
549	struct ibmpex_bmc_data *data = user_msg_data;
550
551	if (msg->msgid != data->tx_msgid) {
552		dev_err(data->bmc_device,
553			"Mismatch between received msgid (%02x) and transmitted msgid (%02x)!\n",
554			(int)msg->msgid,
555			(int)data->tx_msgid);
556		ipmi_free_recv_msg(msg);
557		return;
558	}
559
560	data->rx_recv_type = msg->recv_type;
561	if (msg->msg.data_len > 0)
562		data->rx_result = msg->msg.data[0];
563	else
564		data->rx_result = IPMI_UNKNOWN_ERR_COMPLETION_CODE;
565
566	if (msg->msg.data_len > 1) {
567		data->rx_msg_len = msg->msg.data_len - 1;
568		memcpy(data->rx_msg_data, msg->msg.data + 1, data->rx_msg_len);
569	} else
570		data->rx_msg_len = 0;
571
572	ipmi_free_recv_msg(msg);
573	complete(&data->read_complete);
574}
575
576static int __init ibmpex_init(void)
577{
578	return ipmi_smi_watcher_register(&driver_data.bmc_events);
579}
580
581static void __exit ibmpex_exit(void)
582{
583	struct ibmpex_bmc_data *p, *next;
584
585	ipmi_smi_watcher_unregister(&driver_data.bmc_events);
586	list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
587		ibmpex_bmc_delete(p);
588}
589
590MODULE_AUTHOR("Darrick J. Wong <darrick.wong@oracle.com>");
591MODULE_DESCRIPTION("IBM PowerExecutive power/temperature sensor driver");
592MODULE_LICENSE("GPL");
593
594module_init(ibmpex_init);
595module_exit(ibmpex_exit);
596
597MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3350-*");
598MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3550-*");
599MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3650-*");
600MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3655-*");
601MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3755-*");
602