xref: /openbmc/linux/drivers/hwmon/ibmaem.c (revision a09d2831)
1 /*
2  * A hwmon driver for the IBM System Director Active Energy Manager (AEM)
3  * temperature/power/energy sensors and capping functionality.
4  * Copyright (C) 2008 IBM
5  *
6  * Author: Darrick J. Wong <djwong@us.ibm.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21  */
22 
23 #include <linux/ipmi.h>
24 #include <linux/module.h>
25 #include <linux/hwmon.h>
26 #include <linux/hwmon-sysfs.h>
27 #include <linux/jiffies.h>
28 #include <linux/mutex.h>
29 #include <linux/kdev_t.h>
30 #include <linux/spinlock.h>
31 #include <linux/idr.h>
32 #include <linux/sched.h>
33 #include <linux/platform_device.h>
34 #include <linux/math64.h>
35 #include <linux/time.h>
36 
37 #define REFRESH_INTERVAL	(HZ)
38 #define IPMI_TIMEOUT		(30 * HZ)
39 #define DRVNAME			"aem"
40 
41 #define AEM_NETFN		0x2E
42 
43 #define AEM_FIND_FW_CMD		0x80
44 #define AEM_ELEMENT_CMD		0x81
45 #define AEM_FW_INSTANCE_CMD	0x82
46 
47 #define AEM_READ_ELEMENT_CFG	0x80
48 #define AEM_READ_BUFFER		0x81
49 #define AEM_READ_REGISTER	0x82
50 #define AEM_WRITE_REGISTER	0x83
51 #define AEM_SET_REG_MASK	0x84
52 #define AEM_CLEAR_REG_MASK	0x85
53 #define AEM_READ_ELEMENT_CFG2	0x86
54 
55 #define AEM_CONTROL_ELEMENT	0
56 #define AEM_ENERGY_ELEMENT	1
57 #define AEM_CLOCK_ELEMENT	4
58 #define AEM_POWER_CAP_ELEMENT	7
59 #define AEM_EXHAUST_ELEMENT	9
60 #define AEM_POWER_ELEMENT	10
61 
62 #define AEM_MODULE_TYPE_ID	0x0001
63 
64 #define AEM2_NUM_ENERGY_REGS	2
65 #define AEM2_NUM_PCAP_REGS	6
66 #define AEM2_NUM_TEMP_REGS	2
67 #define AEM2_NUM_SENSORS	14
68 
69 #define AEM1_NUM_ENERGY_REGS	1
70 #define AEM1_NUM_SENSORS	3
71 
72 /* AEM 2.x has more energy registers */
73 #define AEM_NUM_ENERGY_REGS	AEM2_NUM_ENERGY_REGS
74 /* AEM 2.x needs more sensor files */
75 #define AEM_NUM_SENSORS		AEM2_NUM_SENSORS
76 
77 #define POWER_CAP		0
78 #define POWER_CAP_MAX_HOTPLUG	1
79 #define POWER_CAP_MAX		2
80 #define	POWER_CAP_MIN_WARNING	3
81 #define POWER_CAP_MIN		4
82 #define	POWER_AUX		5
83 
84 #define AEM_DEFAULT_POWER_INTERVAL 1000
85 #define AEM_MIN_POWER_INTERVAL	200
86 #define UJ_PER_MJ		1000L
87 
88 static DEFINE_IDR(aem_idr);
89 static DEFINE_SPINLOCK(aem_idr_lock);
90 
91 static struct platform_driver aem_driver = {
92 	.driver = {
93 		.name = DRVNAME,
94 		.bus = &platform_bus_type,
95 	}
96 };
97 
98 struct aem_ipmi_data {
99 	struct completion	read_complete;
100 	struct ipmi_addr	address;
101 	ipmi_user_t		user;
102 	int			interface;
103 
104 	struct kernel_ipmi_msg	tx_message;
105 	long			tx_msgid;
106 
107 	void			*rx_msg_data;
108 	unsigned short		rx_msg_len;
109 	unsigned char		rx_result;
110 	int			rx_recv_type;
111 
112 	struct device		*bmc_device;
113 };
114 
115 struct aem_ro_sensor_template {
116 	char *label;
117 	ssize_t (*show)(struct device *dev,
118 			struct device_attribute *devattr,
119 			char *buf);
120 	int index;
121 };
122 
123 struct aem_rw_sensor_template {
124 	char *label;
125 	ssize_t (*show)(struct device *dev,
126 			struct device_attribute *devattr,
127 			char *buf);
128 	ssize_t (*set)(struct device *dev,
129 		       struct device_attribute *devattr,
130 		       const char *buf, size_t count);
131 	int index;
132 };
133 
134 struct aem_data {
135 	struct list_head	list;
136 
137 	struct device		*hwmon_dev;
138 	struct platform_device	*pdev;
139 	struct mutex		lock;
140 	char			valid;
141 	unsigned long		last_updated;	/* In jiffies */
142 	u8			ver_major;
143 	u8			ver_minor;
144 	u8			module_handle;
145 	int			id;
146 	struct aem_ipmi_data	ipmi;
147 
148 	/* Function to update sensors */
149 	void (*update)(struct aem_data *data);
150 
151 	/*
152 	 * AEM 1.x sensors:
153 	 * Available sensors:
154 	 * Energy meter
155 	 * Power meter
156 	 *
157 	 * AEM 2.x sensors:
158 	 * Two energy meters
159 	 * Two power meters
160 	 * Two temperature sensors
161 	 * Six power cap registers
162 	 */
163 
164 	/* sysfs attrs */
165 	struct sensor_device_attribute	sensors[AEM_NUM_SENSORS];
166 
167 	/* energy use in mJ */
168 	u64			energy[AEM_NUM_ENERGY_REGS];
169 
170 	/* power sampling interval in ms */
171 	unsigned long		power_period[AEM_NUM_ENERGY_REGS];
172 
173 	/* Everything past here is for AEM2 only */
174 
175 	/* power caps in dW */
176 	u16			pcap[AEM2_NUM_PCAP_REGS];
177 
178 	/* exhaust temperature in C */
179 	u8			temp[AEM2_NUM_TEMP_REGS];
180 };
181 
182 /* Data structures returned by the AEM firmware */
183 struct aem_iana_id {
184 	u8			bytes[3];
185 };
186 static struct aem_iana_id system_x_id = {
187 	.bytes = {0x4D, 0x4F, 0x00}
188 };
189 
190 /* These are used to find AEM1 instances */
191 struct aem_find_firmware_req {
192 	struct aem_iana_id	id;
193 	u8			rsvd;
194 	__be16			index;
195 	__be16			module_type_id;
196 } __packed;
197 
198 struct aem_find_firmware_resp {
199 	struct aem_iana_id	id;
200 	u8			num_instances;
201 } __packed;
202 
203 /* These are used to find AEM2 instances */
204 struct aem_find_instance_req {
205 	struct aem_iana_id	id;
206 	u8			instance_number;
207 	__be16			module_type_id;
208 } __packed;
209 
210 struct aem_find_instance_resp {
211 	struct aem_iana_id	id;
212 	u8			num_instances;
213 	u8			major;
214 	u8			minor;
215 	u8			module_handle;
216 	u16			record_id;
217 } __packed;
218 
219 /* These are used to query sensors */
220 struct aem_read_sensor_req {
221 	struct aem_iana_id	id;
222 	u8			module_handle;
223 	u8			element;
224 	u8			subcommand;
225 	u8			reg;
226 	u8			rx_buf_size;
227 } __packed;
228 
229 struct aem_read_sensor_resp {
230 	struct aem_iana_id	id;
231 	u8			bytes[0];
232 } __packed;
233 
234 /* Data structures to talk to the IPMI layer */
235 struct aem_driver_data {
236 	struct list_head	aem_devices;
237 	struct ipmi_smi_watcher	bmc_events;
238 	struct ipmi_user_hndl	ipmi_hndlrs;
239 };
240 
241 static void aem_register_bmc(int iface, struct device *dev);
242 static void aem_bmc_gone(int iface);
243 static void aem_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
244 
245 static void aem_remove_sensors(struct aem_data *data);
246 static int aem_init_aem1(struct aem_ipmi_data *probe);
247 static int aem_init_aem2(struct aem_ipmi_data *probe);
248 static int aem1_find_sensors(struct aem_data *data);
249 static int aem2_find_sensors(struct aem_data *data);
250 static void update_aem1_sensors(struct aem_data *data);
251 static void update_aem2_sensors(struct aem_data *data);
252 
253 static struct aem_driver_data driver_data = {
254 	.aem_devices = LIST_HEAD_INIT(driver_data.aem_devices),
255 	.bmc_events = {
256 		.owner = THIS_MODULE,
257 		.new_smi = aem_register_bmc,
258 		.smi_gone = aem_bmc_gone,
259 	},
260 	.ipmi_hndlrs = {
261 		.ipmi_recv_hndl = aem_msg_handler,
262 	},
263 };
264 
265 /* Functions to talk to the IPMI layer */
266 
267 /* Initialize IPMI address, message buffers and user data */
268 static int aem_init_ipmi_data(struct aem_ipmi_data *data, int iface,
269 			      struct device *bmc)
270 {
271 	int err;
272 
273 	init_completion(&data->read_complete);
274 	data->bmc_device = bmc;
275 
276 	/* Initialize IPMI address */
277 	data->address.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
278 	data->address.channel = IPMI_BMC_CHANNEL;
279 	data->address.data[0] = 0;
280 	data->interface = iface;
281 
282 	/* Initialize message buffers */
283 	data->tx_msgid = 0;
284 	data->tx_message.netfn = AEM_NETFN;
285 
286 	/* Create IPMI messaging interface user */
287 	err = ipmi_create_user(data->interface, &driver_data.ipmi_hndlrs,
288 			       data, &data->user);
289 	if (err < 0) {
290 		dev_err(bmc, "Unable to register user with IPMI "
291 			"interface %d\n", data->interface);
292 		return -EACCES;
293 	}
294 
295 	return 0;
296 }
297 
298 /* Send an IPMI command */
299 static int aem_send_message(struct aem_ipmi_data *data)
300 {
301 	int err;
302 
303 	err = ipmi_validate_addr(&data->address, sizeof(data->address));
304 	if (err)
305 		goto out;
306 
307 	data->tx_msgid++;
308 	err = ipmi_request_settime(data->user, &data->address, data->tx_msgid,
309 				   &data->tx_message, data, 0, 0, 0);
310 	if (err)
311 		goto out1;
312 
313 	return 0;
314 out1:
315 	dev_err(data->bmc_device, "request_settime=%x\n", err);
316 	return err;
317 out:
318 	dev_err(data->bmc_device, "validate_addr=%x\n", err);
319 	return err;
320 }
321 
322 /* Dispatch IPMI messages to callers */
323 static void aem_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
324 {
325 	unsigned short rx_len;
326 	struct aem_ipmi_data *data = user_msg_data;
327 
328 	if (msg->msgid != data->tx_msgid) {
329 		dev_err(data->bmc_device, "Mismatch between received msgid "
330 			"(%02x) and transmitted msgid (%02x)!\n",
331 			(int)msg->msgid,
332 			(int)data->tx_msgid);
333 		ipmi_free_recv_msg(msg);
334 		return;
335 	}
336 
337 	data->rx_recv_type = msg->recv_type;
338 	if (msg->msg.data_len > 0)
339 		data->rx_result = msg->msg.data[0];
340 	else
341 		data->rx_result = IPMI_UNKNOWN_ERR_COMPLETION_CODE;
342 
343 	if (msg->msg.data_len > 1) {
344 		rx_len = msg->msg.data_len - 1;
345 		if (data->rx_msg_len < rx_len)
346 			rx_len = data->rx_msg_len;
347 		data->rx_msg_len = rx_len;
348 		memcpy(data->rx_msg_data, msg->msg.data + 1, data->rx_msg_len);
349 	} else
350 		data->rx_msg_len = 0;
351 
352 	ipmi_free_recv_msg(msg);
353 	complete(&data->read_complete);
354 }
355 
356 /* ID functions */
357 
358 /* Obtain an id */
359 static int aem_idr_get(int *id)
360 {
361 	int i, err;
362 
363 again:
364 	if (unlikely(!idr_pre_get(&aem_idr, GFP_KERNEL)))
365 		return -ENOMEM;
366 
367 	spin_lock(&aem_idr_lock);
368 	err = idr_get_new(&aem_idr, NULL, &i);
369 	spin_unlock(&aem_idr_lock);
370 
371 	if (unlikely(err == -EAGAIN))
372 		goto again;
373 	else if (unlikely(err))
374 		return err;
375 
376 	*id = i & MAX_ID_MASK;
377 	return 0;
378 }
379 
380 /* Release an object ID */
381 static void aem_idr_put(int id)
382 {
383 	spin_lock(&aem_idr_lock);
384 	idr_remove(&aem_idr, id);
385 	spin_unlock(&aem_idr_lock);
386 }
387 
388 /* Sensor support functions */
389 
390 /* Read a sensor value */
391 static int aem_read_sensor(struct aem_data *data, u8 elt, u8 reg,
392 			   void *buf, size_t size)
393 {
394 	int rs_size, res;
395 	struct aem_read_sensor_req rs_req;
396 	struct aem_read_sensor_resp *rs_resp;
397 	struct aem_ipmi_data *ipmi = &data->ipmi;
398 
399 	/* AEM registers are 1, 2, 4 or 8 bytes */
400 	switch (size) {
401 	case 1:
402 	case 2:
403 	case 4:
404 	case 8:
405 		break;
406 	default:
407 		return -EINVAL;
408 	}
409 
410 	rs_req.id = system_x_id;
411 	rs_req.module_handle = data->module_handle;
412 	rs_req.element = elt;
413 	rs_req.subcommand = AEM_READ_REGISTER;
414 	rs_req.reg = reg;
415 	rs_req.rx_buf_size = size;
416 
417 	ipmi->tx_message.cmd = AEM_ELEMENT_CMD;
418 	ipmi->tx_message.data = (char *)&rs_req;
419 	ipmi->tx_message.data_len = sizeof(rs_req);
420 
421 	rs_size = sizeof(*rs_resp) + size;
422 	rs_resp = kzalloc(rs_size, GFP_KERNEL);
423 	if (!rs_resp)
424 		return -ENOMEM;
425 
426 	ipmi->rx_msg_data = rs_resp;
427 	ipmi->rx_msg_len = rs_size;
428 
429 	aem_send_message(ipmi);
430 
431 	res = wait_for_completion_timeout(&ipmi->read_complete, IPMI_TIMEOUT);
432 	if (!res)
433 		return -ETIMEDOUT;
434 
435 	if (ipmi->rx_result || ipmi->rx_msg_len != rs_size ||
436 	    memcmp(&rs_resp->id, &system_x_id, sizeof(system_x_id))) {
437 		kfree(rs_resp);
438 		return -ENOENT;
439 	}
440 
441 	switch (size) {
442 	case 1: {
443 		u8 *x = buf;
444 		*x = rs_resp->bytes[0];
445 		break;
446 	}
447 	case 2: {
448 		u16 *x = buf;
449 		*x = be16_to_cpup((__be16 *)rs_resp->bytes);
450 		break;
451 	}
452 	case 4: {
453 		u32 *x = buf;
454 		*x = be32_to_cpup((__be32 *)rs_resp->bytes);
455 		break;
456 	}
457 	case 8: {
458 		u64 *x = buf;
459 		*x = be64_to_cpup((__be64 *)rs_resp->bytes);
460 		break;
461 	}
462 	}
463 
464 	return 0;
465 }
466 
467 /* Update AEM energy registers */
468 static void update_aem_energy_one(struct aem_data *data, int which)
469 {
470 	aem_read_sensor(data, AEM_ENERGY_ELEMENT, which,
471 			&data->energy[which], 8);
472 }
473 
474 static void update_aem_energy(struct aem_data *data)
475 {
476 	update_aem_energy_one(data, 0);
477 	if (data->ver_major < 2)
478 		return;
479 	update_aem_energy_one(data, 1);
480 }
481 
482 /* Update all AEM1 sensors */
483 static void update_aem1_sensors(struct aem_data *data)
484 {
485 	mutex_lock(&data->lock);
486 	if (time_before(jiffies, data->last_updated + REFRESH_INTERVAL) &&
487 	    data->valid)
488 		goto out;
489 
490 	update_aem_energy(data);
491 out:
492 	mutex_unlock(&data->lock);
493 }
494 
495 /* Update all AEM2 sensors */
496 static void update_aem2_sensors(struct aem_data *data)
497 {
498 	int i;
499 
500 	mutex_lock(&data->lock);
501 	if (time_before(jiffies, data->last_updated + REFRESH_INTERVAL) &&
502 	    data->valid)
503 		goto out;
504 
505 	update_aem_energy(data);
506 	aem_read_sensor(data, AEM_EXHAUST_ELEMENT, 0, &data->temp[0], 1);
507 	aem_read_sensor(data, AEM_EXHAUST_ELEMENT, 1, &data->temp[1], 1);
508 
509 	for (i = POWER_CAP; i <= POWER_AUX; i++)
510 		aem_read_sensor(data, AEM_POWER_CAP_ELEMENT, i,
511 				&data->pcap[i], 2);
512 out:
513 	mutex_unlock(&data->lock);
514 }
515 
516 /* Delete an AEM instance */
517 static void aem_delete(struct aem_data *data)
518 {
519 	list_del(&data->list);
520 	aem_remove_sensors(data);
521 	hwmon_device_unregister(data->hwmon_dev);
522 	ipmi_destroy_user(data->ipmi.user);
523 	dev_set_drvdata(&data->pdev->dev, NULL);
524 	platform_device_unregister(data->pdev);
525 	aem_idr_put(data->id);
526 	kfree(data);
527 }
528 
529 /* Probe functions for AEM1 devices */
530 
531 /* Retrieve version and module handle for an AEM1 instance */
532 static int aem_find_aem1_count(struct aem_ipmi_data *data)
533 {
534 	int res;
535 	struct aem_find_firmware_req	ff_req;
536 	struct aem_find_firmware_resp	ff_resp;
537 
538 	ff_req.id = system_x_id;
539 	ff_req.index = 0;
540 	ff_req.module_type_id = cpu_to_be16(AEM_MODULE_TYPE_ID);
541 
542 	data->tx_message.cmd = AEM_FIND_FW_CMD;
543 	data->tx_message.data = (char *)&ff_req;
544 	data->tx_message.data_len = sizeof(ff_req);
545 
546 	data->rx_msg_data = &ff_resp;
547 	data->rx_msg_len = sizeof(ff_resp);
548 
549 	aem_send_message(data);
550 
551 	res = wait_for_completion_timeout(&data->read_complete, IPMI_TIMEOUT);
552 	if (!res)
553 		return -ETIMEDOUT;
554 
555 	if (data->rx_result || data->rx_msg_len != sizeof(ff_resp) ||
556 	    memcmp(&ff_resp.id, &system_x_id, sizeof(system_x_id)))
557 		return -ENOENT;
558 
559 	return ff_resp.num_instances;
560 }
561 
562 /* Find and initialize one AEM1 instance */
563 static int aem_init_aem1_inst(struct aem_ipmi_data *probe, u8 module_handle)
564 {
565 	struct aem_data *data;
566 	int i;
567 	int res = -ENOMEM;
568 
569 	data = kzalloc(sizeof(*data), GFP_KERNEL);
570 	if (!data)
571 		return res;
572 	mutex_init(&data->lock);
573 
574 	/* Copy instance data */
575 	data->ver_major = 1;
576 	data->ver_minor = 0;
577 	data->module_handle = module_handle;
578 	for (i = 0; i < AEM1_NUM_ENERGY_REGS; i++)
579 		data->power_period[i] = AEM_DEFAULT_POWER_INTERVAL;
580 
581 	/* Create sub-device for this fw instance */
582 	if (aem_idr_get(&data->id))
583 		goto id_err;
584 
585 	data->pdev = platform_device_alloc(DRVNAME, data->id);
586 	if (!data->pdev)
587 		goto dev_err;
588 	data->pdev->dev.driver = &aem_driver.driver;
589 
590 	res = platform_device_add(data->pdev);
591 	if (res)
592 		goto ipmi_err;
593 
594 	dev_set_drvdata(&data->pdev->dev, data);
595 
596 	/* Set up IPMI interface */
597 	if (aem_init_ipmi_data(&data->ipmi, probe->interface,
598 			       probe->bmc_device))
599 		goto ipmi_err;
600 
601 	/* Register with hwmon */
602 	data->hwmon_dev = hwmon_device_register(&data->pdev->dev);
603 
604 	if (IS_ERR(data->hwmon_dev)) {
605 		dev_err(&data->pdev->dev, "Unable to register hwmon "
606 			"device for IPMI interface %d\n",
607 			probe->interface);
608 		goto hwmon_reg_err;
609 	}
610 
611 	data->update = update_aem1_sensors;
612 
613 	/* Find sensors */
614 	if (aem1_find_sensors(data))
615 		goto sensor_err;
616 
617 	/* Add to our list of AEM devices */
618 	list_add_tail(&data->list, &driver_data.aem_devices);
619 
620 	dev_info(data->ipmi.bmc_device, "Found AEM v%d.%d at 0x%X\n",
621 		 data->ver_major, data->ver_minor,
622 		 data->module_handle);
623 	return 0;
624 
625 sensor_err:
626 	hwmon_device_unregister(data->hwmon_dev);
627 hwmon_reg_err:
628 	ipmi_destroy_user(data->ipmi.user);
629 ipmi_err:
630 	dev_set_drvdata(&data->pdev->dev, NULL);
631 	platform_device_unregister(data->pdev);
632 dev_err:
633 	aem_idr_put(data->id);
634 id_err:
635 	kfree(data);
636 
637 	return res;
638 }
639 
640 /* Find and initialize all AEM1 instances */
641 static int aem_init_aem1(struct aem_ipmi_data *probe)
642 {
643 	int num, i, err;
644 
645 	num = aem_find_aem1_count(probe);
646 	for (i = 0; i < num; i++) {
647 		err = aem_init_aem1_inst(probe, i);
648 		if (err) {
649 			dev_err(probe->bmc_device,
650 				"Error %d initializing AEM1 0x%X\n",
651 				err, i);
652 			return err;
653 		}
654 	}
655 
656 	return 0;
657 }
658 
659 /* Probe functions for AEM2 devices */
660 
661 /* Retrieve version and module handle for an AEM2 instance */
662 static int aem_find_aem2(struct aem_ipmi_data *data,
663 			    struct aem_find_instance_resp *fi_resp,
664 			    int instance_num)
665 {
666 	int res;
667 	struct aem_find_instance_req fi_req;
668 
669 	fi_req.id = system_x_id;
670 	fi_req.instance_number = instance_num;
671 	fi_req.module_type_id = cpu_to_be16(AEM_MODULE_TYPE_ID);
672 
673 	data->tx_message.cmd = AEM_FW_INSTANCE_CMD;
674 	data->tx_message.data = (char *)&fi_req;
675 	data->tx_message.data_len = sizeof(fi_req);
676 
677 	data->rx_msg_data = fi_resp;
678 	data->rx_msg_len = sizeof(*fi_resp);
679 
680 	aem_send_message(data);
681 
682 	res = wait_for_completion_timeout(&data->read_complete, IPMI_TIMEOUT);
683 	if (!res)
684 		return -ETIMEDOUT;
685 
686 	if (data->rx_result || data->rx_msg_len != sizeof(*fi_resp) ||
687 	    memcmp(&fi_resp->id, &system_x_id, sizeof(system_x_id)) ||
688 	    fi_resp->num_instances <= instance_num)
689 		return -ENOENT;
690 
691 	return 0;
692 }
693 
694 /* Find and initialize one AEM2 instance */
695 static int aem_init_aem2_inst(struct aem_ipmi_data *probe,
696 			      struct aem_find_instance_resp *fi_resp)
697 {
698 	struct aem_data *data;
699 	int i;
700 	int res = -ENOMEM;
701 
702 	data = kzalloc(sizeof(*data), GFP_KERNEL);
703 	if (!data)
704 		return res;
705 	mutex_init(&data->lock);
706 
707 	/* Copy instance data */
708 	data->ver_major = fi_resp->major;
709 	data->ver_minor = fi_resp->minor;
710 	data->module_handle = fi_resp->module_handle;
711 	for (i = 0; i < AEM2_NUM_ENERGY_REGS; i++)
712 		data->power_period[i] = AEM_DEFAULT_POWER_INTERVAL;
713 
714 	/* Create sub-device for this fw instance */
715 	if (aem_idr_get(&data->id))
716 		goto id_err;
717 
718 	data->pdev = platform_device_alloc(DRVNAME, data->id);
719 	if (!data->pdev)
720 		goto dev_err;
721 	data->pdev->dev.driver = &aem_driver.driver;
722 
723 	res = platform_device_add(data->pdev);
724 	if (res)
725 		goto ipmi_err;
726 
727 	dev_set_drvdata(&data->pdev->dev, data);
728 
729 	/* Set up IPMI interface */
730 	if (aem_init_ipmi_data(&data->ipmi, probe->interface,
731 			       probe->bmc_device))
732 		goto ipmi_err;
733 
734 	/* Register with hwmon */
735 	data->hwmon_dev = hwmon_device_register(&data->pdev->dev);
736 
737 	if (IS_ERR(data->hwmon_dev)) {
738 		dev_err(&data->pdev->dev, "Unable to register hwmon "
739 			"device for IPMI interface %d\n",
740 			probe->interface);
741 		goto hwmon_reg_err;
742 	}
743 
744 	data->update = update_aem2_sensors;
745 
746 	/* Find sensors */
747 	if (aem2_find_sensors(data))
748 		goto sensor_err;
749 
750 	/* Add to our list of AEM devices */
751 	list_add_tail(&data->list, &driver_data.aem_devices);
752 
753 	dev_info(data->ipmi.bmc_device, "Found AEM v%d.%d at 0x%X\n",
754 		 data->ver_major, data->ver_minor,
755 		 data->module_handle);
756 	return 0;
757 
758 sensor_err:
759 	hwmon_device_unregister(data->hwmon_dev);
760 hwmon_reg_err:
761 	ipmi_destroy_user(data->ipmi.user);
762 ipmi_err:
763 	dev_set_drvdata(&data->pdev->dev, NULL);
764 	platform_device_unregister(data->pdev);
765 dev_err:
766 	aem_idr_put(data->id);
767 id_err:
768 	kfree(data);
769 
770 	return res;
771 }
772 
773 /* Find and initialize all AEM2 instances */
774 static int aem_init_aem2(struct aem_ipmi_data *probe)
775 {
776 	struct aem_find_instance_resp fi_resp;
777 	int err;
778 	int i = 0;
779 
780 	while (!aem_find_aem2(probe, &fi_resp, i)) {
781 		if (fi_resp.major != 2) {
782 			dev_err(probe->bmc_device, "Unknown AEM v%d; please "
783 				"report this to the maintainer.\n",
784 				fi_resp.major);
785 			i++;
786 			continue;
787 		}
788 		err = aem_init_aem2_inst(probe, &fi_resp);
789 		if (err) {
790 			dev_err(probe->bmc_device,
791 				"Error %d initializing AEM2 0x%X\n",
792 				err, fi_resp.module_handle);
793 			return err;
794 		}
795 		i++;
796 	}
797 
798 	return 0;
799 }
800 
801 /* Probe a BMC for AEM firmware instances */
802 static void aem_register_bmc(int iface, struct device *dev)
803 {
804 	struct aem_ipmi_data probe;
805 
806 	if (aem_init_ipmi_data(&probe, iface, dev))
807 		return;
808 
809 	/* Ignore probe errors; they won't cause problems */
810 	aem_init_aem1(&probe);
811 	aem_init_aem2(&probe);
812 
813 	ipmi_destroy_user(probe.user);
814 }
815 
816 /* Handle BMC deletion */
817 static void aem_bmc_gone(int iface)
818 {
819 	struct aem_data *p1, *next1;
820 
821 	list_for_each_entry_safe(p1, next1, &driver_data.aem_devices, list)
822 		if (p1->ipmi.interface == iface)
823 			aem_delete(p1);
824 }
825 
826 /* sysfs support functions */
827 
828 /* AEM device name */
829 static ssize_t show_name(struct device *dev, struct device_attribute *devattr,
830 			 char *buf)
831 {
832 	struct aem_data *data = dev_get_drvdata(dev);
833 
834 	return sprintf(buf, "%s%d\n", DRVNAME, data->ver_major);
835 }
836 static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, 0);
837 
838 /* AEM device version */
839 static ssize_t show_version(struct device *dev,
840 			    struct device_attribute *devattr,
841 			    char *buf)
842 {
843 	struct aem_data *data = dev_get_drvdata(dev);
844 
845 	return sprintf(buf, "%d.%d\n", data->ver_major, data->ver_minor);
846 }
847 static SENSOR_DEVICE_ATTR(version, S_IRUGO, show_version, NULL, 0);
848 
849 /* Display power use */
850 static ssize_t aem_show_power(struct device *dev,
851 			      struct device_attribute *devattr,
852 			      char *buf)
853 {
854 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
855 	struct aem_data *data = dev_get_drvdata(dev);
856 	u64 before, after, delta, time;
857 	signed long leftover;
858 	struct timespec b, a;
859 
860 	mutex_lock(&data->lock);
861 	update_aem_energy_one(data, attr->index);
862 	getnstimeofday(&b);
863 	before = data->energy[attr->index];
864 
865 	leftover = schedule_timeout_interruptible(
866 			msecs_to_jiffies(data->power_period[attr->index])
867 		   );
868 	if (leftover) {
869 		mutex_unlock(&data->lock);
870 		return 0;
871 	}
872 
873 	update_aem_energy_one(data, attr->index);
874 	getnstimeofday(&a);
875 	after = data->energy[attr->index];
876 	mutex_unlock(&data->lock);
877 
878 	time = timespec_to_ns(&a) - timespec_to_ns(&b);
879 	delta = (after - before) * UJ_PER_MJ;
880 
881 	return sprintf(buf, "%llu\n",
882 		(unsigned long long)div64_u64(delta * NSEC_PER_SEC, time));
883 }
884 
885 /* Display energy use */
886 static ssize_t aem_show_energy(struct device *dev,
887 			       struct device_attribute *devattr,
888 			       char *buf)
889 {
890 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
891 	struct aem_data *a = dev_get_drvdata(dev);
892 	mutex_lock(&a->lock);
893 	update_aem_energy_one(a, attr->index);
894 	mutex_unlock(&a->lock);
895 
896 	return sprintf(buf, "%llu\n",
897 			(unsigned long long)a->energy[attr->index] * 1000);
898 }
899 
900 /* Display power interval registers */
901 static ssize_t aem_show_power_period(struct device *dev,
902 				     struct device_attribute *devattr,
903 				     char *buf)
904 {
905 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
906 	struct aem_data *a = dev_get_drvdata(dev);
907 	a->update(a);
908 
909 	return sprintf(buf, "%lu\n", a->power_period[attr->index]);
910 }
911 
912 /* Set power interval registers */
913 static ssize_t aem_set_power_period(struct device *dev,
914 				    struct device_attribute *devattr,
915 				    const char *buf, size_t count)
916 {
917 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
918 	struct aem_data *a = dev_get_drvdata(dev);
919 	unsigned long temp;
920 	int res;
921 
922 	res = strict_strtoul(buf, 10, &temp);
923 	if (res)
924 		return res;
925 
926 	if (temp < AEM_MIN_POWER_INTERVAL)
927 		return -EINVAL;
928 
929 	mutex_lock(&a->lock);
930 	a->power_period[attr->index] = temp;
931 	mutex_unlock(&a->lock);
932 
933 	return count;
934 }
935 
936 /* Discover sensors on an AEM device */
937 static int aem_register_sensors(struct aem_data *data,
938 				struct aem_ro_sensor_template *ro,
939 				struct aem_rw_sensor_template *rw)
940 {
941 	struct device *dev = &data->pdev->dev;
942 	struct sensor_device_attribute *sensors = data->sensors;
943 	int err;
944 
945 	/* Set up read-only sensors */
946 	while (ro->label) {
947 		sensors->dev_attr.attr.name = ro->label;
948 		sensors->dev_attr.attr.mode = S_IRUGO;
949 		sensors->dev_attr.show = ro->show;
950 		sensors->index = ro->index;
951 
952 		err = device_create_file(dev, &sensors->dev_attr);
953 		if (err) {
954 			sensors->dev_attr.attr.name = NULL;
955 			goto error;
956 		}
957 		sensors++;
958 		ro++;
959 	}
960 
961 	/* Set up read-write sensors */
962 	while (rw->label) {
963 		sensors->dev_attr.attr.name = rw->label;
964 		sensors->dev_attr.attr.mode = S_IRUGO | S_IWUSR;
965 		sensors->dev_attr.show = rw->show;
966 		sensors->dev_attr.store = rw->set;
967 		sensors->index = rw->index;
968 
969 		err = device_create_file(dev, &sensors->dev_attr);
970 		if (err) {
971 			sensors->dev_attr.attr.name = NULL;
972 			goto error;
973 		}
974 		sensors++;
975 		rw++;
976 	}
977 
978 	err = device_create_file(dev, &sensor_dev_attr_name.dev_attr);
979 	if (err)
980 		goto error;
981 	err = device_create_file(dev, &sensor_dev_attr_version.dev_attr);
982 	return err;
983 
984 error:
985 	aem_remove_sensors(data);
986 	return err;
987 }
988 
989 /* sysfs support functions for AEM2 sensors */
990 
991 /* Display temperature use */
992 static ssize_t aem2_show_temp(struct device *dev,
993 			      struct device_attribute *devattr,
994 			      char *buf)
995 {
996 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
997 	struct aem_data *a = dev_get_drvdata(dev);
998 	a->update(a);
999 
1000 	return sprintf(buf, "%u\n", a->temp[attr->index] * 1000);
1001 }
1002 
1003 /* Display power-capping registers */
1004 static ssize_t aem2_show_pcap_value(struct device *dev,
1005 				    struct device_attribute *devattr,
1006 				    char *buf)
1007 {
1008 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
1009 	struct aem_data *a = dev_get_drvdata(dev);
1010 	a->update(a);
1011 
1012 	return sprintf(buf, "%u\n", a->pcap[attr->index] * 100000);
1013 }
1014 
1015 /* Remove sensors attached to an AEM device */
1016 static void aem_remove_sensors(struct aem_data *data)
1017 {
1018 	int i;
1019 
1020 	for (i = 0; i < AEM_NUM_SENSORS; i++) {
1021 		if (!data->sensors[i].dev_attr.attr.name)
1022 			continue;
1023 		device_remove_file(&data->pdev->dev,
1024 				   &data->sensors[i].dev_attr);
1025 	}
1026 
1027 	device_remove_file(&data->pdev->dev,
1028 			   &sensor_dev_attr_name.dev_attr);
1029 	device_remove_file(&data->pdev->dev,
1030 			   &sensor_dev_attr_version.dev_attr);
1031 }
1032 
1033 /* Sensor probe functions */
1034 
1035 /* Description of AEM1 sensors */
1036 static struct aem_ro_sensor_template aem1_ro_sensors[] = {
1037 {"energy1_input",  aem_show_energy, 0},
1038 {"power1_average", aem_show_power,  0},
1039 {NULL,		   NULL,	    0},
1040 };
1041 
1042 static struct aem_rw_sensor_template aem1_rw_sensors[] = {
1043 {"power1_average_interval", aem_show_power_period, aem_set_power_period, 0},
1044 {NULL,			    NULL,                  NULL,                 0},
1045 };
1046 
1047 /* Description of AEM2 sensors */
1048 static struct aem_ro_sensor_template aem2_ro_sensors[] = {
1049 {"energy1_input",	  aem_show_energy,	0},
1050 {"energy2_input",	  aem_show_energy,	1},
1051 {"power1_average",	  aem_show_power,	0},
1052 {"power2_average",	  aem_show_power,	1},
1053 {"temp1_input",		  aem2_show_temp,	0},
1054 {"temp2_input",		  aem2_show_temp,	1},
1055 
1056 {"power4_average",	  aem2_show_pcap_value,	POWER_CAP_MAX_HOTPLUG},
1057 {"power5_average",	  aem2_show_pcap_value,	POWER_CAP_MAX},
1058 {"power6_average",	  aem2_show_pcap_value,	POWER_CAP_MIN_WARNING},
1059 {"power7_average",	  aem2_show_pcap_value,	POWER_CAP_MIN},
1060 
1061 {"power3_average", 	  aem2_show_pcap_value,	POWER_AUX},
1062 {"power_cap",		  aem2_show_pcap_value,	POWER_CAP},
1063 {NULL,                    NULL,                 0},
1064 };
1065 
1066 static struct aem_rw_sensor_template aem2_rw_sensors[] = {
1067 {"power1_average_interval", aem_show_power_period, aem_set_power_period, 0},
1068 {"power2_average_interval", aem_show_power_period, aem_set_power_period, 1},
1069 {NULL,			    NULL,                  NULL,                 0},
1070 };
1071 
1072 /* Set up AEM1 sensor attrs */
1073 static int aem1_find_sensors(struct aem_data *data)
1074 {
1075 	return aem_register_sensors(data, aem1_ro_sensors, aem1_rw_sensors);
1076 }
1077 
1078 /* Set up AEM2 sensor attrs */
1079 static int aem2_find_sensors(struct aem_data *data)
1080 {
1081 	return aem_register_sensors(data, aem2_ro_sensors, aem2_rw_sensors);
1082 }
1083 
1084 /* Module init/exit routines */
1085 
1086 static int __init aem_init(void)
1087 {
1088 	int res;
1089 
1090 	res = driver_register(&aem_driver.driver);
1091 	if (res) {
1092 		printk(KERN_ERR "Can't register aem driver\n");
1093 		return res;
1094 	}
1095 
1096 	res = ipmi_smi_watcher_register(&driver_data.bmc_events);
1097 	if (res)
1098 		goto ipmi_reg_err;
1099 	return 0;
1100 
1101 ipmi_reg_err:
1102 	driver_unregister(&aem_driver.driver);
1103 	return res;
1104 
1105 }
1106 
1107 static void __exit aem_exit(void)
1108 {
1109 	struct aem_data *p1, *next1;
1110 
1111 	ipmi_smi_watcher_unregister(&driver_data.bmc_events);
1112 	driver_unregister(&aem_driver.driver);
1113 	list_for_each_entry_safe(p1, next1, &driver_data.aem_devices, list)
1114 		aem_delete(p1);
1115 }
1116 
1117 MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
1118 MODULE_DESCRIPTION("IBM AEM power/temp/energy sensor driver");
1119 MODULE_LICENSE("GPL");
1120 
1121 module_init(aem_init);
1122 module_exit(aem_exit);
1123 
1124 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3350-*");
1125 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3550-*");
1126 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3650-*");
1127 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3655-*");
1128 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3755-*");
1129 MODULE_ALIAS("dmi:bvnIBM:*:pnIBM3850M2/x3950M2-*");
1130 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMBladeHC10-*");
1131