xref: /openbmc/linux/drivers/hwmon/occ/common.c (revision 11a163f2)
1 // SPDX-License-Identifier: GPL-2.0+
2 // Copyright IBM Corp 2019
3 
4 #include <linux/device.h>
5 #include <linux/export.h>
6 #include <linux/hwmon.h>
7 #include <linux/hwmon-sysfs.h>
8 #include <linux/jiffies.h>
9 #include <linux/kernel.h>
10 #include <linux/math64.h>
11 #include <linux/module.h>
12 #include <linux/mutex.h>
13 #include <linux/sysfs.h>
14 #include <asm/unaligned.h>
15 
16 #include "common.h"
17 
18 #define EXTN_FLAG_SENSOR_ID		BIT(7)
19 
20 #define OCC_ERROR_COUNT_THRESHOLD	2	/* required by OCC spec */
21 
22 #define OCC_STATE_SAFE			4
23 #define OCC_SAFE_TIMEOUT		msecs_to_jiffies(60000) /* 1 min */
24 
25 #define OCC_UPDATE_FREQUENCY		msecs_to_jiffies(1000)
26 
27 #define OCC_TEMP_SENSOR_FAULT		0xFF
28 
29 #define OCC_FRU_TYPE_VRM		3
30 
31 /* OCC sensor type and version definitions */
32 
33 struct temp_sensor_1 {
34 	u16 sensor_id;
35 	u16 value;
36 } __packed;
37 
38 struct temp_sensor_2 {
39 	u32 sensor_id;
40 	u8 fru_type;
41 	u8 value;
42 } __packed;
43 
44 struct freq_sensor_1 {
45 	u16 sensor_id;
46 	u16 value;
47 } __packed;
48 
49 struct freq_sensor_2 {
50 	u32 sensor_id;
51 	u16 value;
52 } __packed;
53 
54 struct power_sensor_1 {
55 	u16 sensor_id;
56 	u32 update_tag;
57 	u32 accumulator;
58 	u16 value;
59 } __packed;
60 
61 struct power_sensor_2 {
62 	u32 sensor_id;
63 	u8 function_id;
64 	u8 apss_channel;
65 	u16 reserved;
66 	u32 update_tag;
67 	u64 accumulator;
68 	u16 value;
69 } __packed;
70 
71 struct power_sensor_data {
72 	u16 value;
73 	u32 update_tag;
74 	u64 accumulator;
75 } __packed;
76 
77 struct power_sensor_data_and_time {
78 	u16 update_time;
79 	u16 value;
80 	u32 update_tag;
81 	u64 accumulator;
82 } __packed;
83 
84 struct power_sensor_a0 {
85 	u32 sensor_id;
86 	struct power_sensor_data_and_time system;
87 	u32 reserved;
88 	struct power_sensor_data_and_time proc;
89 	struct power_sensor_data vdd;
90 	struct power_sensor_data vdn;
91 } __packed;
92 
93 struct caps_sensor_2 {
94 	u16 cap;
95 	u16 system_power;
96 	u16 n_cap;
97 	u16 max;
98 	u16 min;
99 	u16 user;
100 	u8 user_source;
101 } __packed;
102 
103 struct caps_sensor_3 {
104 	u16 cap;
105 	u16 system_power;
106 	u16 n_cap;
107 	u16 max;
108 	u16 hard_min;
109 	u16 soft_min;
110 	u16 user;
111 	u8 user_source;
112 } __packed;
113 
114 struct extended_sensor {
115 	union {
116 		u8 name[4];
117 		u32 sensor_id;
118 	};
119 	u8 flags;
120 	u8 reserved;
121 	u8 data[6];
122 } __packed;
123 
124 static int occ_poll(struct occ *occ)
125 {
126 	int rc;
127 	u16 checksum = occ->poll_cmd_data + occ->seq_no + 1;
128 	u8 cmd[8];
129 	struct occ_poll_response_header *header;
130 
131 	/* big endian */
132 	cmd[0] = occ->seq_no++;		/* sequence number */
133 	cmd[1] = 0;			/* cmd type */
134 	cmd[2] = 0;			/* data length msb */
135 	cmd[3] = 1;			/* data length lsb */
136 	cmd[4] = occ->poll_cmd_data;	/* data */
137 	cmd[5] = checksum >> 8;		/* checksum msb */
138 	cmd[6] = checksum & 0xFF;	/* checksum lsb */
139 	cmd[7] = 0;
140 
141 	/* mutex should already be locked if necessary */
142 	rc = occ->send_cmd(occ, cmd);
143 	if (rc) {
144 		occ->last_error = rc;
145 		if (occ->error_count++ > OCC_ERROR_COUNT_THRESHOLD)
146 			occ->error = rc;
147 
148 		goto done;
149 	}
150 
151 	/* clear error since communication was successful */
152 	occ->error_count = 0;
153 	occ->last_error = 0;
154 	occ->error = 0;
155 
156 	/* check for safe state */
157 	header = (struct occ_poll_response_header *)occ->resp.data;
158 	if (header->occ_state == OCC_STATE_SAFE) {
159 		if (occ->last_safe) {
160 			if (time_after(jiffies,
161 				       occ->last_safe + OCC_SAFE_TIMEOUT))
162 				occ->error = -EHOSTDOWN;
163 		} else {
164 			occ->last_safe = jiffies;
165 		}
166 	} else {
167 		occ->last_safe = 0;
168 	}
169 
170 done:
171 	occ_sysfs_poll_done(occ);
172 	return rc;
173 }
174 
175 static int occ_set_user_power_cap(struct occ *occ, u16 user_power_cap)
176 {
177 	int rc;
178 	u8 cmd[8];
179 	u16 checksum = 0x24;
180 	__be16 user_power_cap_be = cpu_to_be16(user_power_cap);
181 
182 	cmd[0] = 0;
183 	cmd[1] = 0x22;
184 	cmd[2] = 0;
185 	cmd[3] = 2;
186 
187 	memcpy(&cmd[4], &user_power_cap_be, 2);
188 
189 	checksum += cmd[4] + cmd[5];
190 	cmd[6] = checksum >> 8;
191 	cmd[7] = checksum & 0xFF;
192 
193 	rc = mutex_lock_interruptible(&occ->lock);
194 	if (rc)
195 		return rc;
196 
197 	rc = occ->send_cmd(occ, cmd);
198 
199 	mutex_unlock(&occ->lock);
200 
201 	return rc;
202 }
203 
204 int occ_update_response(struct occ *occ)
205 {
206 	int rc = mutex_lock_interruptible(&occ->lock);
207 
208 	if (rc)
209 		return rc;
210 
211 	/* limit the maximum rate of polling the OCC */
212 	if (time_after(jiffies, occ->last_update + OCC_UPDATE_FREQUENCY)) {
213 		rc = occ_poll(occ);
214 		occ->last_update = jiffies;
215 	} else {
216 		rc = occ->last_error;
217 	}
218 
219 	mutex_unlock(&occ->lock);
220 	return rc;
221 }
222 
223 static ssize_t occ_show_temp_1(struct device *dev,
224 			       struct device_attribute *attr, char *buf)
225 {
226 	int rc;
227 	u32 val = 0;
228 	struct temp_sensor_1 *temp;
229 	struct occ *occ = dev_get_drvdata(dev);
230 	struct occ_sensors *sensors = &occ->sensors;
231 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
232 
233 	rc = occ_update_response(occ);
234 	if (rc)
235 		return rc;
236 
237 	temp = ((struct temp_sensor_1 *)sensors->temp.data) + sattr->index;
238 
239 	switch (sattr->nr) {
240 	case 0:
241 		val = get_unaligned_be16(&temp->sensor_id);
242 		break;
243 	case 1:
244 		/*
245 		 * If a sensor reading has expired and couldn't be refreshed,
246 		 * OCC returns 0xFFFF for that sensor.
247 		 */
248 		if (temp->value == 0xFFFF)
249 			return -EREMOTEIO;
250 		val = get_unaligned_be16(&temp->value) * 1000;
251 		break;
252 	default:
253 		return -EINVAL;
254 	}
255 
256 	return snprintf(buf, PAGE_SIZE - 1, "%u\n", val);
257 }
258 
259 static ssize_t occ_show_temp_2(struct device *dev,
260 			       struct device_attribute *attr, char *buf)
261 {
262 	int rc;
263 	u32 val = 0;
264 	struct temp_sensor_2 *temp;
265 	struct occ *occ = dev_get_drvdata(dev);
266 	struct occ_sensors *sensors = &occ->sensors;
267 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
268 
269 	rc = occ_update_response(occ);
270 	if (rc)
271 		return rc;
272 
273 	temp = ((struct temp_sensor_2 *)sensors->temp.data) + sattr->index;
274 
275 	switch (sattr->nr) {
276 	case 0:
277 		val = get_unaligned_be32(&temp->sensor_id);
278 		break;
279 	case 1:
280 		val = temp->value;
281 		if (val == OCC_TEMP_SENSOR_FAULT)
282 			return -EREMOTEIO;
283 
284 		/*
285 		 * VRM doesn't return temperature, only alarm bit. This
286 		 * attribute maps to tempX_alarm instead of tempX_input for
287 		 * VRM
288 		 */
289 		if (temp->fru_type != OCC_FRU_TYPE_VRM) {
290 			/* sensor not ready */
291 			if (val == 0)
292 				return -EAGAIN;
293 
294 			val *= 1000;
295 		}
296 		break;
297 	case 2:
298 		val = temp->fru_type;
299 		break;
300 	case 3:
301 		val = temp->value == OCC_TEMP_SENSOR_FAULT;
302 		break;
303 	default:
304 		return -EINVAL;
305 	}
306 
307 	return snprintf(buf, PAGE_SIZE - 1, "%u\n", val);
308 }
309 
310 static ssize_t occ_show_freq_1(struct device *dev,
311 			       struct device_attribute *attr, char *buf)
312 {
313 	int rc;
314 	u16 val = 0;
315 	struct freq_sensor_1 *freq;
316 	struct occ *occ = dev_get_drvdata(dev);
317 	struct occ_sensors *sensors = &occ->sensors;
318 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
319 
320 	rc = occ_update_response(occ);
321 	if (rc)
322 		return rc;
323 
324 	freq = ((struct freq_sensor_1 *)sensors->freq.data) + sattr->index;
325 
326 	switch (sattr->nr) {
327 	case 0:
328 		val = get_unaligned_be16(&freq->sensor_id);
329 		break;
330 	case 1:
331 		val = get_unaligned_be16(&freq->value);
332 		break;
333 	default:
334 		return -EINVAL;
335 	}
336 
337 	return snprintf(buf, PAGE_SIZE - 1, "%u\n", val);
338 }
339 
340 static ssize_t occ_show_freq_2(struct device *dev,
341 			       struct device_attribute *attr, char *buf)
342 {
343 	int rc;
344 	u32 val = 0;
345 	struct freq_sensor_2 *freq;
346 	struct occ *occ = dev_get_drvdata(dev);
347 	struct occ_sensors *sensors = &occ->sensors;
348 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
349 
350 	rc = occ_update_response(occ);
351 	if (rc)
352 		return rc;
353 
354 	freq = ((struct freq_sensor_2 *)sensors->freq.data) + sattr->index;
355 
356 	switch (sattr->nr) {
357 	case 0:
358 		val = get_unaligned_be32(&freq->sensor_id);
359 		break;
360 	case 1:
361 		val = get_unaligned_be16(&freq->value);
362 		break;
363 	default:
364 		return -EINVAL;
365 	}
366 
367 	return snprintf(buf, PAGE_SIZE - 1, "%u\n", val);
368 }
369 
370 static ssize_t occ_show_power_1(struct device *dev,
371 				struct device_attribute *attr, char *buf)
372 {
373 	int rc;
374 	u64 val = 0;
375 	struct power_sensor_1 *power;
376 	struct occ *occ = dev_get_drvdata(dev);
377 	struct occ_sensors *sensors = &occ->sensors;
378 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
379 
380 	rc = occ_update_response(occ);
381 	if (rc)
382 		return rc;
383 
384 	power = ((struct power_sensor_1 *)sensors->power.data) + sattr->index;
385 
386 	switch (sattr->nr) {
387 	case 0:
388 		val = get_unaligned_be16(&power->sensor_id);
389 		break;
390 	case 1:
391 		val = get_unaligned_be32(&power->accumulator) /
392 			get_unaligned_be32(&power->update_tag);
393 		val *= 1000000ULL;
394 		break;
395 	case 2:
396 		val = (u64)get_unaligned_be32(&power->update_tag) *
397 			   occ->powr_sample_time_us;
398 		break;
399 	case 3:
400 		val = get_unaligned_be16(&power->value) * 1000000ULL;
401 		break;
402 	default:
403 		return -EINVAL;
404 	}
405 
406 	return snprintf(buf, PAGE_SIZE - 1, "%llu\n", val);
407 }
408 
409 static u64 occ_get_powr_avg(u64 *accum, u32 *samples)
410 {
411 	u64 divisor = get_unaligned_be32(samples);
412 
413 	return (divisor == 0) ? 0 :
414 		div64_u64(get_unaligned_be64(accum) * 1000000ULL, divisor);
415 }
416 
417 static ssize_t occ_show_power_2(struct device *dev,
418 				struct device_attribute *attr, char *buf)
419 {
420 	int rc;
421 	u64 val = 0;
422 	struct power_sensor_2 *power;
423 	struct occ *occ = dev_get_drvdata(dev);
424 	struct occ_sensors *sensors = &occ->sensors;
425 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
426 
427 	rc = occ_update_response(occ);
428 	if (rc)
429 		return rc;
430 
431 	power = ((struct power_sensor_2 *)sensors->power.data) + sattr->index;
432 
433 	switch (sattr->nr) {
434 	case 0:
435 		return snprintf(buf, PAGE_SIZE - 1, "%u_%u_%u\n",
436 				get_unaligned_be32(&power->sensor_id),
437 				power->function_id, power->apss_channel);
438 	case 1:
439 		val = occ_get_powr_avg(&power->accumulator,
440 				       &power->update_tag);
441 		break;
442 	case 2:
443 		val = (u64)get_unaligned_be32(&power->update_tag) *
444 			   occ->powr_sample_time_us;
445 		break;
446 	case 3:
447 		val = get_unaligned_be16(&power->value) * 1000000ULL;
448 		break;
449 	default:
450 		return -EINVAL;
451 	}
452 
453 	return snprintf(buf, PAGE_SIZE - 1, "%llu\n", val);
454 }
455 
456 static ssize_t occ_show_power_a0(struct device *dev,
457 				 struct device_attribute *attr, char *buf)
458 {
459 	int rc;
460 	u64 val = 0;
461 	struct power_sensor_a0 *power;
462 	struct occ *occ = dev_get_drvdata(dev);
463 	struct occ_sensors *sensors = &occ->sensors;
464 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
465 
466 	rc = occ_update_response(occ);
467 	if (rc)
468 		return rc;
469 
470 	power = ((struct power_sensor_a0 *)sensors->power.data) + sattr->index;
471 
472 	switch (sattr->nr) {
473 	case 0:
474 		return snprintf(buf, PAGE_SIZE - 1, "%u_system\n",
475 				get_unaligned_be32(&power->sensor_id));
476 	case 1:
477 		val = occ_get_powr_avg(&power->system.accumulator,
478 				       &power->system.update_tag);
479 		break;
480 	case 2:
481 		val = (u64)get_unaligned_be32(&power->system.update_tag) *
482 			   occ->powr_sample_time_us;
483 		break;
484 	case 3:
485 		val = get_unaligned_be16(&power->system.value) * 1000000ULL;
486 		break;
487 	case 4:
488 		return snprintf(buf, PAGE_SIZE - 1, "%u_proc\n",
489 				get_unaligned_be32(&power->sensor_id));
490 	case 5:
491 		val = occ_get_powr_avg(&power->proc.accumulator,
492 				       &power->proc.update_tag);
493 		break;
494 	case 6:
495 		val = (u64)get_unaligned_be32(&power->proc.update_tag) *
496 			   occ->powr_sample_time_us;
497 		break;
498 	case 7:
499 		val = get_unaligned_be16(&power->proc.value) * 1000000ULL;
500 		break;
501 	case 8:
502 		return snprintf(buf, PAGE_SIZE - 1, "%u_vdd\n",
503 				get_unaligned_be32(&power->sensor_id));
504 	case 9:
505 		val = occ_get_powr_avg(&power->vdd.accumulator,
506 				       &power->vdd.update_tag);
507 		break;
508 	case 10:
509 		val = (u64)get_unaligned_be32(&power->vdd.update_tag) *
510 			   occ->powr_sample_time_us;
511 		break;
512 	case 11:
513 		val = get_unaligned_be16(&power->vdd.value) * 1000000ULL;
514 		break;
515 	case 12:
516 		return snprintf(buf, PAGE_SIZE - 1, "%u_vdn\n",
517 				get_unaligned_be32(&power->sensor_id));
518 	case 13:
519 		val = occ_get_powr_avg(&power->vdn.accumulator,
520 				       &power->vdn.update_tag);
521 		break;
522 	case 14:
523 		val = (u64)get_unaligned_be32(&power->vdn.update_tag) *
524 			   occ->powr_sample_time_us;
525 		break;
526 	case 15:
527 		val = get_unaligned_be16(&power->vdn.value) * 1000000ULL;
528 		break;
529 	default:
530 		return -EINVAL;
531 	}
532 
533 	return snprintf(buf, PAGE_SIZE - 1, "%llu\n", val);
534 }
535 
536 static ssize_t occ_show_caps_1_2(struct device *dev,
537 				 struct device_attribute *attr, char *buf)
538 {
539 	int rc;
540 	u64 val = 0;
541 	struct caps_sensor_2 *caps;
542 	struct occ *occ = dev_get_drvdata(dev);
543 	struct occ_sensors *sensors = &occ->sensors;
544 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
545 
546 	rc = occ_update_response(occ);
547 	if (rc)
548 		return rc;
549 
550 	caps = ((struct caps_sensor_2 *)sensors->caps.data) + sattr->index;
551 
552 	switch (sattr->nr) {
553 	case 0:
554 		return snprintf(buf, PAGE_SIZE - 1, "system\n");
555 	case 1:
556 		val = get_unaligned_be16(&caps->cap) * 1000000ULL;
557 		break;
558 	case 2:
559 		val = get_unaligned_be16(&caps->system_power) * 1000000ULL;
560 		break;
561 	case 3:
562 		val = get_unaligned_be16(&caps->n_cap) * 1000000ULL;
563 		break;
564 	case 4:
565 		val = get_unaligned_be16(&caps->max) * 1000000ULL;
566 		break;
567 	case 5:
568 		val = get_unaligned_be16(&caps->min) * 1000000ULL;
569 		break;
570 	case 6:
571 		val = get_unaligned_be16(&caps->user) * 1000000ULL;
572 		break;
573 	case 7:
574 		if (occ->sensors.caps.version == 1)
575 			return -EINVAL;
576 
577 		val = caps->user_source;
578 		break;
579 	default:
580 		return -EINVAL;
581 	}
582 
583 	return snprintf(buf, PAGE_SIZE - 1, "%llu\n", val);
584 }
585 
586 static ssize_t occ_show_caps_3(struct device *dev,
587 			       struct device_attribute *attr, char *buf)
588 {
589 	int rc;
590 	u64 val = 0;
591 	struct caps_sensor_3 *caps;
592 	struct occ *occ = dev_get_drvdata(dev);
593 	struct occ_sensors *sensors = &occ->sensors;
594 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
595 
596 	rc = occ_update_response(occ);
597 	if (rc)
598 		return rc;
599 
600 	caps = ((struct caps_sensor_3 *)sensors->caps.data) + sattr->index;
601 
602 	switch (sattr->nr) {
603 	case 0:
604 		return snprintf(buf, PAGE_SIZE - 1, "system\n");
605 	case 1:
606 		val = get_unaligned_be16(&caps->cap) * 1000000ULL;
607 		break;
608 	case 2:
609 		val = get_unaligned_be16(&caps->system_power) * 1000000ULL;
610 		break;
611 	case 3:
612 		val = get_unaligned_be16(&caps->n_cap) * 1000000ULL;
613 		break;
614 	case 4:
615 		val = get_unaligned_be16(&caps->max) * 1000000ULL;
616 		break;
617 	case 5:
618 		val = get_unaligned_be16(&caps->hard_min) * 1000000ULL;
619 		break;
620 	case 6:
621 		val = get_unaligned_be16(&caps->user) * 1000000ULL;
622 		break;
623 	case 7:
624 		val = caps->user_source;
625 		break;
626 	default:
627 		return -EINVAL;
628 	}
629 
630 	return snprintf(buf, PAGE_SIZE - 1, "%llu\n", val);
631 }
632 
633 static ssize_t occ_store_caps_user(struct device *dev,
634 				   struct device_attribute *attr,
635 				   const char *buf, size_t count)
636 {
637 	int rc;
638 	u16 user_power_cap;
639 	unsigned long long value;
640 	struct occ *occ = dev_get_drvdata(dev);
641 
642 	rc = kstrtoull(buf, 0, &value);
643 	if (rc)
644 		return rc;
645 
646 	user_power_cap = div64_u64(value, 1000000ULL); /* microwatt to watt */
647 
648 	rc = occ_set_user_power_cap(occ, user_power_cap);
649 	if (rc)
650 		return rc;
651 
652 	return count;
653 }
654 
655 static ssize_t occ_show_extended(struct device *dev,
656 				 struct device_attribute *attr, char *buf)
657 {
658 	int rc;
659 	struct extended_sensor *extn;
660 	struct occ *occ = dev_get_drvdata(dev);
661 	struct occ_sensors *sensors = &occ->sensors;
662 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
663 
664 	rc = occ_update_response(occ);
665 	if (rc)
666 		return rc;
667 
668 	extn = ((struct extended_sensor *)sensors->extended.data) +
669 		sattr->index;
670 
671 	switch (sattr->nr) {
672 	case 0:
673 		if (extn->flags & EXTN_FLAG_SENSOR_ID)
674 			rc = snprintf(buf, PAGE_SIZE - 1, "%u",
675 				      get_unaligned_be32(&extn->sensor_id));
676 		else
677 			rc = snprintf(buf, PAGE_SIZE - 1, "%02x%02x%02x%02x\n",
678 				      extn->name[0], extn->name[1],
679 				      extn->name[2], extn->name[3]);
680 		break;
681 	case 1:
682 		rc = snprintf(buf, PAGE_SIZE - 1, "%02x\n", extn->flags);
683 		break;
684 	case 2:
685 		rc = snprintf(buf, PAGE_SIZE - 1, "%02x%02x%02x%02x%02x%02x\n",
686 			      extn->data[0], extn->data[1], extn->data[2],
687 			      extn->data[3], extn->data[4], extn->data[5]);
688 		break;
689 	default:
690 		return -EINVAL;
691 	}
692 
693 	return rc;
694 }
695 
696 /*
697  * Some helper macros to make it easier to define an occ_attribute. Since these
698  * are dynamically allocated, we shouldn't use the existing kernel macros which
699  * stringify the name argument.
700  */
701 #define ATTR_OCC(_name, _mode, _show, _store) {				\
702 	.attr	= {							\
703 		.name = _name,						\
704 		.mode = VERIFY_OCTAL_PERMISSIONS(_mode),		\
705 	},								\
706 	.show	= _show,						\
707 	.store	= _store,						\
708 }
709 
710 #define SENSOR_ATTR_OCC(_name, _mode, _show, _store, _nr, _index) {	\
711 	.dev_attr	= ATTR_OCC(_name, _mode, _show, _store),	\
712 	.index		= _index,					\
713 	.nr		= _nr,						\
714 }
715 
716 #define OCC_INIT_ATTR(_name, _mode, _show, _store, _nr, _index)		\
717 	((struct sensor_device_attribute_2)				\
718 		SENSOR_ATTR_OCC(_name, _mode, _show, _store, _nr, _index))
719 
720 /*
721  * Allocate and instatiate sensor_device_attribute_2s. It's most efficient to
722  * use our own instead of the built-in hwmon attribute types.
723  */
724 static int occ_setup_sensor_attrs(struct occ *occ)
725 {
726 	unsigned int i, s, num_attrs = 0;
727 	struct device *dev = occ->bus_dev;
728 	struct occ_sensors *sensors = &occ->sensors;
729 	struct occ_attribute *attr;
730 	struct temp_sensor_2 *temp;
731 	ssize_t (*show_temp)(struct device *, struct device_attribute *,
732 			     char *) = occ_show_temp_1;
733 	ssize_t (*show_freq)(struct device *, struct device_attribute *,
734 			     char *) = occ_show_freq_1;
735 	ssize_t (*show_power)(struct device *, struct device_attribute *,
736 			      char *) = occ_show_power_1;
737 	ssize_t (*show_caps)(struct device *, struct device_attribute *,
738 			     char *) = occ_show_caps_1_2;
739 
740 	switch (sensors->temp.version) {
741 	case 1:
742 		num_attrs += (sensors->temp.num_sensors * 2);
743 		break;
744 	case 2:
745 		num_attrs += (sensors->temp.num_sensors * 4);
746 		show_temp = occ_show_temp_2;
747 		break;
748 	default:
749 		sensors->temp.num_sensors = 0;
750 	}
751 
752 	switch (sensors->freq.version) {
753 	case 2:
754 		show_freq = occ_show_freq_2;
755 		fallthrough;
756 	case 1:
757 		num_attrs += (sensors->freq.num_sensors * 2);
758 		break;
759 	default:
760 		sensors->freq.num_sensors = 0;
761 	}
762 
763 	switch (sensors->power.version) {
764 	case 2:
765 		show_power = occ_show_power_2;
766 		fallthrough;
767 	case 1:
768 		num_attrs += (sensors->power.num_sensors * 4);
769 		break;
770 	case 0xA0:
771 		num_attrs += (sensors->power.num_sensors * 16);
772 		show_power = occ_show_power_a0;
773 		break;
774 	default:
775 		sensors->power.num_sensors = 0;
776 	}
777 
778 	switch (sensors->caps.version) {
779 	case 1:
780 		num_attrs += (sensors->caps.num_sensors * 7);
781 		break;
782 	case 3:
783 		show_caps = occ_show_caps_3;
784 		fallthrough;
785 	case 2:
786 		num_attrs += (sensors->caps.num_sensors * 8);
787 		break;
788 	default:
789 		sensors->caps.num_sensors = 0;
790 	}
791 
792 	switch (sensors->extended.version) {
793 	case 1:
794 		num_attrs += (sensors->extended.num_sensors * 3);
795 		break;
796 	default:
797 		sensors->extended.num_sensors = 0;
798 	}
799 
800 	occ->attrs = devm_kzalloc(dev, sizeof(*occ->attrs) * num_attrs,
801 				  GFP_KERNEL);
802 	if (!occ->attrs)
803 		return -ENOMEM;
804 
805 	/* null-terminated list */
806 	occ->group.attrs = devm_kzalloc(dev, sizeof(*occ->group.attrs) *
807 					num_attrs + 1, GFP_KERNEL);
808 	if (!occ->group.attrs)
809 		return -ENOMEM;
810 
811 	attr = occ->attrs;
812 
813 	for (i = 0; i < sensors->temp.num_sensors; ++i) {
814 		s = i + 1;
815 		temp = ((struct temp_sensor_2 *)sensors->temp.data) + i;
816 
817 		snprintf(attr->name, sizeof(attr->name), "temp%d_label", s);
818 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_temp, NULL,
819 					     0, i);
820 		attr++;
821 
822 		if (sensors->temp.version > 1 &&
823 		    temp->fru_type == OCC_FRU_TYPE_VRM) {
824 			snprintf(attr->name, sizeof(attr->name),
825 				 "temp%d_alarm", s);
826 		} else {
827 			snprintf(attr->name, sizeof(attr->name),
828 				 "temp%d_input", s);
829 		}
830 
831 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_temp, NULL,
832 					     1, i);
833 		attr++;
834 
835 		if (sensors->temp.version > 1) {
836 			snprintf(attr->name, sizeof(attr->name),
837 				 "temp%d_fru_type", s);
838 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
839 						     show_temp, NULL, 2, i);
840 			attr++;
841 
842 			snprintf(attr->name, sizeof(attr->name),
843 				 "temp%d_fault", s);
844 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
845 						     show_temp, NULL, 3, i);
846 			attr++;
847 		}
848 	}
849 
850 	for (i = 0; i < sensors->freq.num_sensors; ++i) {
851 		s = i + 1;
852 
853 		snprintf(attr->name, sizeof(attr->name), "freq%d_label", s);
854 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_freq, NULL,
855 					     0, i);
856 		attr++;
857 
858 		snprintf(attr->name, sizeof(attr->name), "freq%d_input", s);
859 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_freq, NULL,
860 					     1, i);
861 		attr++;
862 	}
863 
864 	if (sensors->power.version == 0xA0) {
865 		/*
866 		 * Special case for many-attribute power sensor. Split it into
867 		 * a sensor number per power type, emulating several sensors.
868 		 */
869 		for (i = 0; i < sensors->power.num_sensors; ++i) {
870 			unsigned int j;
871 			unsigned int nr = 0;
872 
873 			s = (i * 4) + 1;
874 
875 			for (j = 0; j < 4; ++j) {
876 				snprintf(attr->name, sizeof(attr->name),
877 					 "power%d_label", s);
878 				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
879 							     show_power, NULL,
880 							     nr++, i);
881 				attr++;
882 
883 				snprintf(attr->name, sizeof(attr->name),
884 					 "power%d_average", s);
885 				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
886 							     show_power, NULL,
887 							     nr++, i);
888 				attr++;
889 
890 				snprintf(attr->name, sizeof(attr->name),
891 					 "power%d_average_interval", s);
892 				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
893 							     show_power, NULL,
894 							     nr++, i);
895 				attr++;
896 
897 				snprintf(attr->name, sizeof(attr->name),
898 					 "power%d_input", s);
899 				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
900 							     show_power, NULL,
901 							     nr++, i);
902 				attr++;
903 
904 				s++;
905 			}
906 		}
907 
908 		s = (sensors->power.num_sensors * 4) + 1;
909 	} else {
910 		for (i = 0; i < sensors->power.num_sensors; ++i) {
911 			s = i + 1;
912 
913 			snprintf(attr->name, sizeof(attr->name),
914 				 "power%d_label", s);
915 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
916 						     show_power, NULL, 0, i);
917 			attr++;
918 
919 			snprintf(attr->name, sizeof(attr->name),
920 				 "power%d_average", s);
921 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
922 						     show_power, NULL, 1, i);
923 			attr++;
924 
925 			snprintf(attr->name, sizeof(attr->name),
926 				 "power%d_average_interval", s);
927 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
928 						     show_power, NULL, 2, i);
929 			attr++;
930 
931 			snprintf(attr->name, sizeof(attr->name),
932 				 "power%d_input", s);
933 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
934 						     show_power, NULL, 3, i);
935 			attr++;
936 		}
937 
938 		s = sensors->power.num_sensors + 1;
939 	}
940 
941 	if (sensors->caps.num_sensors >= 1) {
942 		snprintf(attr->name, sizeof(attr->name), "power%d_label", s);
943 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
944 					     0, 0);
945 		attr++;
946 
947 		snprintf(attr->name, sizeof(attr->name), "power%d_cap", s);
948 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
949 					     1, 0);
950 		attr++;
951 
952 		snprintf(attr->name, sizeof(attr->name), "power%d_input", s);
953 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
954 					     2, 0);
955 		attr++;
956 
957 		snprintf(attr->name, sizeof(attr->name),
958 			 "power%d_cap_not_redundant", s);
959 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
960 					     3, 0);
961 		attr++;
962 
963 		snprintf(attr->name, sizeof(attr->name), "power%d_cap_max", s);
964 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
965 					     4, 0);
966 		attr++;
967 
968 		snprintf(attr->name, sizeof(attr->name), "power%d_cap_min", s);
969 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
970 					     5, 0);
971 		attr++;
972 
973 		snprintf(attr->name, sizeof(attr->name), "power%d_cap_user",
974 			 s);
975 		attr->sensor = OCC_INIT_ATTR(attr->name, 0644, show_caps,
976 					     occ_store_caps_user, 6, 0);
977 		attr++;
978 
979 		if (sensors->caps.version > 1) {
980 			snprintf(attr->name, sizeof(attr->name),
981 				 "power%d_cap_user_source", s);
982 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
983 						     show_caps, NULL, 7, 0);
984 			attr++;
985 		}
986 	}
987 
988 	for (i = 0; i < sensors->extended.num_sensors; ++i) {
989 		s = i + 1;
990 
991 		snprintf(attr->name, sizeof(attr->name), "extn%d_label", s);
992 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
993 					     occ_show_extended, NULL, 0, i);
994 		attr++;
995 
996 		snprintf(attr->name, sizeof(attr->name), "extn%d_flags", s);
997 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
998 					     occ_show_extended, NULL, 1, i);
999 		attr++;
1000 
1001 		snprintf(attr->name, sizeof(attr->name), "extn%d_input", s);
1002 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
1003 					     occ_show_extended, NULL, 2, i);
1004 		attr++;
1005 	}
1006 
1007 	/* put the sensors in the group */
1008 	for (i = 0; i < num_attrs; ++i) {
1009 		sysfs_attr_init(&occ->attrs[i].sensor.dev_attr.attr);
1010 		occ->group.attrs[i] = &occ->attrs[i].sensor.dev_attr.attr;
1011 	}
1012 
1013 	return 0;
1014 }
1015 
1016 /* only need to do this once at startup, as OCC won't change sensors on us */
1017 static void occ_parse_poll_response(struct occ *occ)
1018 {
1019 	unsigned int i, old_offset, offset = 0, size = 0;
1020 	struct occ_sensor *sensor;
1021 	struct occ_sensors *sensors = &occ->sensors;
1022 	struct occ_response *resp = &occ->resp;
1023 	struct occ_poll_response *poll =
1024 		(struct occ_poll_response *)&resp->data[0];
1025 	struct occ_poll_response_header *header = &poll->header;
1026 	struct occ_sensor_data_block *block = &poll->block;
1027 
1028 	dev_info(occ->bus_dev, "OCC found, code level: %.16s\n",
1029 		 header->occ_code_level);
1030 
1031 	for (i = 0; i < header->num_sensor_data_blocks; ++i) {
1032 		block = (struct occ_sensor_data_block *)((u8 *)block + offset);
1033 		old_offset = offset;
1034 		offset = (block->header.num_sensors *
1035 			  block->header.sensor_length) + sizeof(block->header);
1036 		size += offset;
1037 
1038 		/* validate all the length/size fields */
1039 		if ((size + sizeof(*header)) >= OCC_RESP_DATA_BYTES) {
1040 			dev_warn(occ->bus_dev, "exceeded response buffer\n");
1041 			return;
1042 		}
1043 
1044 		dev_dbg(occ->bus_dev, " %04x..%04x: %.4s (%d sensors)\n",
1045 			old_offset, offset - 1, block->header.eye_catcher,
1046 			block->header.num_sensors);
1047 
1048 		/* match sensor block type */
1049 		if (strncmp(block->header.eye_catcher, "TEMP", 4) == 0)
1050 			sensor = &sensors->temp;
1051 		else if (strncmp(block->header.eye_catcher, "FREQ", 4) == 0)
1052 			sensor = &sensors->freq;
1053 		else if (strncmp(block->header.eye_catcher, "POWR", 4) == 0)
1054 			sensor = &sensors->power;
1055 		else if (strncmp(block->header.eye_catcher, "CAPS", 4) == 0)
1056 			sensor = &sensors->caps;
1057 		else if (strncmp(block->header.eye_catcher, "EXTN", 4) == 0)
1058 			sensor = &sensors->extended;
1059 		else {
1060 			dev_warn(occ->bus_dev, "sensor not supported %.4s\n",
1061 				 block->header.eye_catcher);
1062 			continue;
1063 		}
1064 
1065 		sensor->num_sensors = block->header.num_sensors;
1066 		sensor->version = block->header.sensor_format;
1067 		sensor->data = &block->data;
1068 	}
1069 
1070 	dev_dbg(occ->bus_dev, "Max resp size: %u+%zd=%zd\n", size,
1071 		sizeof(*header), size + sizeof(*header));
1072 }
1073 
1074 int occ_setup(struct occ *occ, const char *name)
1075 {
1076 	int rc;
1077 
1078 	mutex_init(&occ->lock);
1079 	occ->groups[0] = &occ->group;
1080 
1081 	/* no need to lock */
1082 	rc = occ_poll(occ);
1083 	if (rc == -ESHUTDOWN) {
1084 		dev_info(occ->bus_dev, "host is not ready\n");
1085 		return rc;
1086 	} else if (rc < 0) {
1087 		dev_err(occ->bus_dev, "failed to get OCC poll response: %d\n",
1088 			rc);
1089 		return rc;
1090 	}
1091 
1092 	occ_parse_poll_response(occ);
1093 
1094 	rc = occ_setup_sensor_attrs(occ);
1095 	if (rc) {
1096 		dev_err(occ->bus_dev, "failed to setup sensor attrs: %d\n",
1097 			rc);
1098 		return rc;
1099 	}
1100 
1101 	occ->hwmon = devm_hwmon_device_register_with_groups(occ->bus_dev, name,
1102 							    occ, occ->groups);
1103 	if (IS_ERR(occ->hwmon)) {
1104 		rc = PTR_ERR(occ->hwmon);
1105 		dev_err(occ->bus_dev, "failed to register hwmon device: %d\n",
1106 			rc);
1107 		return rc;
1108 	}
1109 
1110 	rc = occ_setup_sysfs(occ);
1111 	if (rc)
1112 		dev_err(occ->bus_dev, "failed to setup sysfs: %d\n", rc);
1113 
1114 	return rc;
1115 }
1116 EXPORT_SYMBOL_GPL(occ_setup);
1117 
1118 MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>");
1119 MODULE_DESCRIPTION("Common OCC hwmon code");
1120 MODULE_LICENSE("GPL");
1121