xref: /openbmc/linux/drivers/hwmon/occ/common.c (revision a9d85efb)
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 temp_sensor_10 {
45 	u32 sensor_id;
46 	u8 fru_type;
47 	u8 value;
48 	u8 throttle;
49 	u8 reserved;
50 } __packed;
51 
52 struct freq_sensor_1 {
53 	u16 sensor_id;
54 	u16 value;
55 } __packed;
56 
57 struct freq_sensor_2 {
58 	u32 sensor_id;
59 	u16 value;
60 } __packed;
61 
62 struct power_sensor_1 {
63 	u16 sensor_id;
64 	u32 update_tag;
65 	u32 accumulator;
66 	u16 value;
67 } __packed;
68 
69 struct power_sensor_2 {
70 	u32 sensor_id;
71 	u8 function_id;
72 	u8 apss_channel;
73 	u16 reserved;
74 	u32 update_tag;
75 	u64 accumulator;
76 	u16 value;
77 } __packed;
78 
79 struct power_sensor_data {
80 	u16 value;
81 	u32 update_tag;
82 	u64 accumulator;
83 } __packed;
84 
85 struct power_sensor_data_and_time {
86 	u16 update_time;
87 	u16 value;
88 	u32 update_tag;
89 	u64 accumulator;
90 } __packed;
91 
92 struct power_sensor_a0 {
93 	u32 sensor_id;
94 	struct power_sensor_data_and_time system;
95 	u32 reserved;
96 	struct power_sensor_data_and_time proc;
97 	struct power_sensor_data vdd;
98 	struct power_sensor_data vdn;
99 } __packed;
100 
101 struct caps_sensor_2 {
102 	u16 cap;
103 	u16 system_power;
104 	u16 n_cap;
105 	u16 max;
106 	u16 min;
107 	u16 user;
108 	u8 user_source;
109 } __packed;
110 
111 struct caps_sensor_3 {
112 	u16 cap;
113 	u16 system_power;
114 	u16 n_cap;
115 	u16 max;
116 	u16 hard_min;
117 	u16 soft_min;
118 	u16 user;
119 	u8 user_source;
120 } __packed;
121 
122 struct extended_sensor {
123 	union {
124 		u8 name[4];
125 		u32 sensor_id;
126 	};
127 	u8 flags;
128 	u8 reserved;
129 	u8 data[6];
130 } __packed;
131 
132 static int occ_poll(struct occ *occ)
133 {
134 	int rc;
135 	u16 checksum = occ->poll_cmd_data + occ->seq_no + 1;
136 	u8 cmd[8];
137 	struct occ_poll_response_header *header;
138 
139 	/* big endian */
140 	cmd[0] = occ->seq_no++;		/* sequence number */
141 	cmd[1] = 0;			/* cmd type */
142 	cmd[2] = 0;			/* data length msb */
143 	cmd[3] = 1;			/* data length lsb */
144 	cmd[4] = occ->poll_cmd_data;	/* data */
145 	cmd[5] = checksum >> 8;		/* checksum msb */
146 	cmd[6] = checksum & 0xFF;	/* checksum lsb */
147 	cmd[7] = 0;
148 
149 	/* mutex should already be locked if necessary */
150 	rc = occ->send_cmd(occ, cmd);
151 	if (rc) {
152 		occ->last_error = rc;
153 		if (occ->error_count++ > OCC_ERROR_COUNT_THRESHOLD)
154 			occ->error = rc;
155 
156 		goto done;
157 	}
158 
159 	/* clear error since communication was successful */
160 	occ->error_count = 0;
161 	occ->last_error = 0;
162 	occ->error = 0;
163 
164 	/* check for safe state */
165 	header = (struct occ_poll_response_header *)occ->resp.data;
166 	if (header->occ_state == OCC_STATE_SAFE) {
167 		if (occ->last_safe) {
168 			if (time_after(jiffies,
169 				       occ->last_safe + OCC_SAFE_TIMEOUT))
170 				occ->error = -EHOSTDOWN;
171 		} else {
172 			occ->last_safe = jiffies;
173 		}
174 	} else {
175 		occ->last_safe = 0;
176 	}
177 
178 done:
179 	occ_sysfs_poll_done(occ);
180 	return rc;
181 }
182 
183 static int occ_set_user_power_cap(struct occ *occ, u16 user_power_cap)
184 {
185 	int rc;
186 	u8 cmd[8];
187 	u16 checksum = 0x24;
188 	__be16 user_power_cap_be = cpu_to_be16(user_power_cap);
189 
190 	cmd[0] = 0;
191 	cmd[1] = 0x22;
192 	cmd[2] = 0;
193 	cmd[3] = 2;
194 
195 	memcpy(&cmd[4], &user_power_cap_be, 2);
196 
197 	checksum += cmd[4] + cmd[5];
198 	cmd[6] = checksum >> 8;
199 	cmd[7] = checksum & 0xFF;
200 
201 	rc = mutex_lock_interruptible(&occ->lock);
202 	if (rc)
203 		return rc;
204 
205 	rc = occ->send_cmd(occ, cmd);
206 
207 	mutex_unlock(&occ->lock);
208 
209 	return rc;
210 }
211 
212 int occ_update_response(struct occ *occ)
213 {
214 	int rc = mutex_lock_interruptible(&occ->lock);
215 
216 	if (rc)
217 		return rc;
218 
219 	/* limit the maximum rate of polling the OCC */
220 	if (time_after(jiffies, occ->next_update)) {
221 		rc = occ_poll(occ);
222 		occ->next_update = jiffies + OCC_UPDATE_FREQUENCY;
223 	} else {
224 		rc = occ->last_error;
225 	}
226 
227 	mutex_unlock(&occ->lock);
228 	return rc;
229 }
230 
231 static ssize_t occ_show_temp_1(struct device *dev,
232 			       struct device_attribute *attr, char *buf)
233 {
234 	int rc;
235 	u32 val = 0;
236 	struct temp_sensor_1 *temp;
237 	struct occ *occ = dev_get_drvdata(dev);
238 	struct occ_sensors *sensors = &occ->sensors;
239 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
240 
241 	rc = occ_update_response(occ);
242 	if (rc)
243 		return rc;
244 
245 	temp = ((struct temp_sensor_1 *)sensors->temp.data) + sattr->index;
246 
247 	switch (sattr->nr) {
248 	case 0:
249 		val = get_unaligned_be16(&temp->sensor_id);
250 		break;
251 	case 1:
252 		/*
253 		 * If a sensor reading has expired and couldn't be refreshed,
254 		 * OCC returns 0xFFFF for that sensor.
255 		 */
256 		if (temp->value == 0xFFFF)
257 			return -EREMOTEIO;
258 		val = get_unaligned_be16(&temp->value) * 1000;
259 		break;
260 	default:
261 		return -EINVAL;
262 	}
263 
264 	return sysfs_emit(buf, "%u\n", val);
265 }
266 
267 static ssize_t occ_show_temp_2(struct device *dev,
268 			       struct device_attribute *attr, char *buf)
269 {
270 	int rc;
271 	u32 val = 0;
272 	struct temp_sensor_2 *temp;
273 	struct occ *occ = dev_get_drvdata(dev);
274 	struct occ_sensors *sensors = &occ->sensors;
275 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
276 
277 	rc = occ_update_response(occ);
278 	if (rc)
279 		return rc;
280 
281 	temp = ((struct temp_sensor_2 *)sensors->temp.data) + sattr->index;
282 
283 	switch (sattr->nr) {
284 	case 0:
285 		val = get_unaligned_be32(&temp->sensor_id);
286 		break;
287 	case 1:
288 		val = temp->value;
289 		if (val == OCC_TEMP_SENSOR_FAULT)
290 			return -EREMOTEIO;
291 
292 		/*
293 		 * VRM doesn't return temperature, only alarm bit. This
294 		 * attribute maps to tempX_alarm instead of tempX_input for
295 		 * VRM
296 		 */
297 		if (temp->fru_type != OCC_FRU_TYPE_VRM) {
298 			/* sensor not ready */
299 			if (val == 0)
300 				return -EAGAIN;
301 
302 			val *= 1000;
303 		}
304 		break;
305 	case 2:
306 		val = temp->fru_type;
307 		break;
308 	case 3:
309 		val = temp->value == OCC_TEMP_SENSOR_FAULT;
310 		break;
311 	default:
312 		return -EINVAL;
313 	}
314 
315 	return sysfs_emit(buf, "%u\n", val);
316 }
317 
318 static ssize_t occ_show_temp_10(struct device *dev,
319 				struct device_attribute *attr, char *buf)
320 {
321 	int rc;
322 	u32 val = 0;
323 	struct temp_sensor_10 *temp;
324 	struct occ *occ = dev_get_drvdata(dev);
325 	struct occ_sensors *sensors = &occ->sensors;
326 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
327 
328 	rc = occ_update_response(occ);
329 	if (rc)
330 		return rc;
331 
332 	temp = ((struct temp_sensor_10 *)sensors->temp.data) + sattr->index;
333 
334 	switch (sattr->nr) {
335 	case 0:
336 		val = get_unaligned_be32(&temp->sensor_id);
337 		break;
338 	case 1:
339 		val = temp->value;
340 		if (val == OCC_TEMP_SENSOR_FAULT)
341 			return -EREMOTEIO;
342 
343 		/* sensor not ready */
344 		if (val == 0)
345 			return -EAGAIN;
346 
347 		val *= 1000;
348 		break;
349 	case 2:
350 		val = temp->fru_type;
351 		break;
352 	case 3:
353 		val = temp->value == OCC_TEMP_SENSOR_FAULT;
354 		break;
355 	case 4:
356 		val = temp->throttle * 1000;
357 		break;
358 	default:
359 		return -EINVAL;
360 	}
361 
362 	return sysfs_emit(buf, "%u\n", val);
363 }
364 
365 static ssize_t occ_show_freq_1(struct device *dev,
366 			       struct device_attribute *attr, char *buf)
367 {
368 	int rc;
369 	u16 val = 0;
370 	struct freq_sensor_1 *freq;
371 	struct occ *occ = dev_get_drvdata(dev);
372 	struct occ_sensors *sensors = &occ->sensors;
373 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
374 
375 	rc = occ_update_response(occ);
376 	if (rc)
377 		return rc;
378 
379 	freq = ((struct freq_sensor_1 *)sensors->freq.data) + sattr->index;
380 
381 	switch (sattr->nr) {
382 	case 0:
383 		val = get_unaligned_be16(&freq->sensor_id);
384 		break;
385 	case 1:
386 		val = get_unaligned_be16(&freq->value);
387 		break;
388 	default:
389 		return -EINVAL;
390 	}
391 
392 	return sysfs_emit(buf, "%u\n", val);
393 }
394 
395 static ssize_t occ_show_freq_2(struct device *dev,
396 			       struct device_attribute *attr, char *buf)
397 {
398 	int rc;
399 	u32 val = 0;
400 	struct freq_sensor_2 *freq;
401 	struct occ *occ = dev_get_drvdata(dev);
402 	struct occ_sensors *sensors = &occ->sensors;
403 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
404 
405 	rc = occ_update_response(occ);
406 	if (rc)
407 		return rc;
408 
409 	freq = ((struct freq_sensor_2 *)sensors->freq.data) + sattr->index;
410 
411 	switch (sattr->nr) {
412 	case 0:
413 		val = get_unaligned_be32(&freq->sensor_id);
414 		break;
415 	case 1:
416 		val = get_unaligned_be16(&freq->value);
417 		break;
418 	default:
419 		return -EINVAL;
420 	}
421 
422 	return sysfs_emit(buf, "%u\n", val);
423 }
424 
425 static ssize_t occ_show_power_1(struct device *dev,
426 				struct device_attribute *attr, char *buf)
427 {
428 	int rc;
429 	u64 val = 0;
430 	struct power_sensor_1 *power;
431 	struct occ *occ = dev_get_drvdata(dev);
432 	struct occ_sensors *sensors = &occ->sensors;
433 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
434 
435 	rc = occ_update_response(occ);
436 	if (rc)
437 		return rc;
438 
439 	power = ((struct power_sensor_1 *)sensors->power.data) + sattr->index;
440 
441 	switch (sattr->nr) {
442 	case 0:
443 		val = get_unaligned_be16(&power->sensor_id);
444 		break;
445 	case 1:
446 		val = get_unaligned_be32(&power->accumulator) /
447 			get_unaligned_be32(&power->update_tag);
448 		val *= 1000000ULL;
449 		break;
450 	case 2:
451 		val = (u64)get_unaligned_be32(&power->update_tag) *
452 			   occ->powr_sample_time_us;
453 		break;
454 	case 3:
455 		val = get_unaligned_be16(&power->value) * 1000000ULL;
456 		break;
457 	default:
458 		return -EINVAL;
459 	}
460 
461 	return sysfs_emit(buf, "%llu\n", val);
462 }
463 
464 static u64 occ_get_powr_avg(u64 *accum, u32 *samples)
465 {
466 	u64 divisor = get_unaligned_be32(samples);
467 
468 	return (divisor == 0) ? 0 :
469 		div64_u64(get_unaligned_be64(accum) * 1000000ULL, divisor);
470 }
471 
472 static ssize_t occ_show_power_2(struct device *dev,
473 				struct device_attribute *attr, char *buf)
474 {
475 	int rc;
476 	u64 val = 0;
477 	struct power_sensor_2 *power;
478 	struct occ *occ = dev_get_drvdata(dev);
479 	struct occ_sensors *sensors = &occ->sensors;
480 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
481 
482 	rc = occ_update_response(occ);
483 	if (rc)
484 		return rc;
485 
486 	power = ((struct power_sensor_2 *)sensors->power.data) + sattr->index;
487 
488 	switch (sattr->nr) {
489 	case 0:
490 		return sysfs_emit(buf, "%u_%u_%u\n",
491 				  get_unaligned_be32(&power->sensor_id),
492 				  power->function_id, power->apss_channel);
493 	case 1:
494 		val = occ_get_powr_avg(&power->accumulator,
495 				       &power->update_tag);
496 		break;
497 	case 2:
498 		val = (u64)get_unaligned_be32(&power->update_tag) *
499 			   occ->powr_sample_time_us;
500 		break;
501 	case 3:
502 		val = get_unaligned_be16(&power->value) * 1000000ULL;
503 		break;
504 	default:
505 		return -EINVAL;
506 	}
507 
508 	return sysfs_emit(buf, "%llu\n", val);
509 }
510 
511 static ssize_t occ_show_power_a0(struct device *dev,
512 				 struct device_attribute *attr, char *buf)
513 {
514 	int rc;
515 	u64 val = 0;
516 	struct power_sensor_a0 *power;
517 	struct occ *occ = dev_get_drvdata(dev);
518 	struct occ_sensors *sensors = &occ->sensors;
519 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
520 
521 	rc = occ_update_response(occ);
522 	if (rc)
523 		return rc;
524 
525 	power = ((struct power_sensor_a0 *)sensors->power.data) + sattr->index;
526 
527 	switch (sattr->nr) {
528 	case 0:
529 		return sysfs_emit(buf, "%u_system\n",
530 				  get_unaligned_be32(&power->sensor_id));
531 	case 1:
532 		val = occ_get_powr_avg(&power->system.accumulator,
533 				       &power->system.update_tag);
534 		break;
535 	case 2:
536 		val = (u64)get_unaligned_be32(&power->system.update_tag) *
537 			   occ->powr_sample_time_us;
538 		break;
539 	case 3:
540 		val = get_unaligned_be16(&power->system.value) * 1000000ULL;
541 		break;
542 	case 4:
543 		return sysfs_emit(buf, "%u_proc\n",
544 				  get_unaligned_be32(&power->sensor_id));
545 	case 5:
546 		val = occ_get_powr_avg(&power->proc.accumulator,
547 				       &power->proc.update_tag);
548 		break;
549 	case 6:
550 		val = (u64)get_unaligned_be32(&power->proc.update_tag) *
551 			   occ->powr_sample_time_us;
552 		break;
553 	case 7:
554 		val = get_unaligned_be16(&power->proc.value) * 1000000ULL;
555 		break;
556 	case 8:
557 		return sysfs_emit(buf, "%u_vdd\n",
558 				  get_unaligned_be32(&power->sensor_id));
559 	case 9:
560 		val = occ_get_powr_avg(&power->vdd.accumulator,
561 				       &power->vdd.update_tag);
562 		break;
563 	case 10:
564 		val = (u64)get_unaligned_be32(&power->vdd.update_tag) *
565 			   occ->powr_sample_time_us;
566 		break;
567 	case 11:
568 		val = get_unaligned_be16(&power->vdd.value) * 1000000ULL;
569 		break;
570 	case 12:
571 		return sysfs_emit(buf, "%u_vdn\n",
572 				  get_unaligned_be32(&power->sensor_id));
573 	case 13:
574 		val = occ_get_powr_avg(&power->vdn.accumulator,
575 				       &power->vdn.update_tag);
576 		break;
577 	case 14:
578 		val = (u64)get_unaligned_be32(&power->vdn.update_tag) *
579 			   occ->powr_sample_time_us;
580 		break;
581 	case 15:
582 		val = get_unaligned_be16(&power->vdn.value) * 1000000ULL;
583 		break;
584 	default:
585 		return -EINVAL;
586 	}
587 
588 	return sysfs_emit(buf, "%llu\n", val);
589 }
590 
591 static ssize_t occ_show_caps_1_2(struct device *dev,
592 				 struct device_attribute *attr, char *buf)
593 {
594 	int rc;
595 	u64 val = 0;
596 	struct caps_sensor_2 *caps;
597 	struct occ *occ = dev_get_drvdata(dev);
598 	struct occ_sensors *sensors = &occ->sensors;
599 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
600 
601 	rc = occ_update_response(occ);
602 	if (rc)
603 		return rc;
604 
605 	caps = ((struct caps_sensor_2 *)sensors->caps.data) + sattr->index;
606 
607 	switch (sattr->nr) {
608 	case 0:
609 		return sysfs_emit(buf, "system\n");
610 	case 1:
611 		val = get_unaligned_be16(&caps->cap) * 1000000ULL;
612 		break;
613 	case 2:
614 		val = get_unaligned_be16(&caps->system_power) * 1000000ULL;
615 		break;
616 	case 3:
617 		val = get_unaligned_be16(&caps->n_cap) * 1000000ULL;
618 		break;
619 	case 4:
620 		val = get_unaligned_be16(&caps->max) * 1000000ULL;
621 		break;
622 	case 5:
623 		val = get_unaligned_be16(&caps->min) * 1000000ULL;
624 		break;
625 	case 6:
626 		val = get_unaligned_be16(&caps->user) * 1000000ULL;
627 		break;
628 	case 7:
629 		if (occ->sensors.caps.version == 1)
630 			return -EINVAL;
631 
632 		val = caps->user_source;
633 		break;
634 	default:
635 		return -EINVAL;
636 	}
637 
638 	return sysfs_emit(buf, "%llu\n", val);
639 }
640 
641 static ssize_t occ_show_caps_3(struct device *dev,
642 			       struct device_attribute *attr, char *buf)
643 {
644 	int rc;
645 	u64 val = 0;
646 	struct caps_sensor_3 *caps;
647 	struct occ *occ = dev_get_drvdata(dev);
648 	struct occ_sensors *sensors = &occ->sensors;
649 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
650 
651 	rc = occ_update_response(occ);
652 	if (rc)
653 		return rc;
654 
655 	caps = ((struct caps_sensor_3 *)sensors->caps.data) + sattr->index;
656 
657 	switch (sattr->nr) {
658 	case 0:
659 		return sysfs_emit(buf, "system\n");
660 	case 1:
661 		val = get_unaligned_be16(&caps->cap) * 1000000ULL;
662 		break;
663 	case 2:
664 		val = get_unaligned_be16(&caps->system_power) * 1000000ULL;
665 		break;
666 	case 3:
667 		val = get_unaligned_be16(&caps->n_cap) * 1000000ULL;
668 		break;
669 	case 4:
670 		val = get_unaligned_be16(&caps->max) * 1000000ULL;
671 		break;
672 	case 5:
673 		val = get_unaligned_be16(&caps->hard_min) * 1000000ULL;
674 		break;
675 	case 6:
676 		val = get_unaligned_be16(&caps->user) * 1000000ULL;
677 		break;
678 	case 7:
679 		val = caps->user_source;
680 		break;
681 	default:
682 		return -EINVAL;
683 	}
684 
685 	return sysfs_emit(buf, "%llu\n", val);
686 }
687 
688 static ssize_t occ_store_caps_user(struct device *dev,
689 				   struct device_attribute *attr,
690 				   const char *buf, size_t count)
691 {
692 	int rc;
693 	u16 user_power_cap;
694 	unsigned long long value;
695 	struct occ *occ = dev_get_drvdata(dev);
696 
697 	rc = kstrtoull(buf, 0, &value);
698 	if (rc)
699 		return rc;
700 
701 	user_power_cap = div64_u64(value, 1000000ULL); /* microwatt to watt */
702 
703 	rc = occ_set_user_power_cap(occ, user_power_cap);
704 	if (rc)
705 		return rc;
706 
707 	return count;
708 }
709 
710 static ssize_t occ_show_extended(struct device *dev,
711 				 struct device_attribute *attr, char *buf)
712 {
713 	int rc;
714 	struct extended_sensor *extn;
715 	struct occ *occ = dev_get_drvdata(dev);
716 	struct occ_sensors *sensors = &occ->sensors;
717 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
718 
719 	rc = occ_update_response(occ);
720 	if (rc)
721 		return rc;
722 
723 	extn = ((struct extended_sensor *)sensors->extended.data) +
724 		sattr->index;
725 
726 	switch (sattr->nr) {
727 	case 0:
728 		if (extn->flags & EXTN_FLAG_SENSOR_ID) {
729 			rc = sysfs_emit(buf, "%u",
730 					get_unaligned_be32(&extn->sensor_id));
731 		} else {
732 			rc = sysfs_emit(buf, "%02x%02x%02x%02x\n",
733 					extn->name[0], extn->name[1],
734 					extn->name[2], extn->name[3]);
735 		}
736 		break;
737 	case 1:
738 		rc = sysfs_emit(buf, "%02x\n", extn->flags);
739 		break;
740 	case 2:
741 		rc = sysfs_emit(buf, "%02x%02x%02x%02x%02x%02x\n",
742 				extn->data[0], extn->data[1], extn->data[2],
743 				extn->data[3], extn->data[4], extn->data[5]);
744 		break;
745 	default:
746 		return -EINVAL;
747 	}
748 
749 	return rc;
750 }
751 
752 /*
753  * Some helper macros to make it easier to define an occ_attribute. Since these
754  * are dynamically allocated, we shouldn't use the existing kernel macros which
755  * stringify the name argument.
756  */
757 #define ATTR_OCC(_name, _mode, _show, _store) {				\
758 	.attr	= {							\
759 		.name = _name,						\
760 		.mode = VERIFY_OCTAL_PERMISSIONS(_mode),		\
761 	},								\
762 	.show	= _show,						\
763 	.store	= _store,						\
764 }
765 
766 #define SENSOR_ATTR_OCC(_name, _mode, _show, _store, _nr, _index) {	\
767 	.dev_attr	= ATTR_OCC(_name, _mode, _show, _store),	\
768 	.index		= _index,					\
769 	.nr		= _nr,						\
770 }
771 
772 #define OCC_INIT_ATTR(_name, _mode, _show, _store, _nr, _index)		\
773 	((struct sensor_device_attribute_2)				\
774 		SENSOR_ATTR_OCC(_name, _mode, _show, _store, _nr, _index))
775 
776 /*
777  * Allocate and instatiate sensor_device_attribute_2s. It's most efficient to
778  * use our own instead of the built-in hwmon attribute types.
779  */
780 static int occ_setup_sensor_attrs(struct occ *occ)
781 {
782 	unsigned int i, s, num_attrs = 0;
783 	struct device *dev = occ->bus_dev;
784 	struct occ_sensors *sensors = &occ->sensors;
785 	struct occ_attribute *attr;
786 	struct temp_sensor_2 *temp;
787 	ssize_t (*show_temp)(struct device *, struct device_attribute *,
788 			     char *) = occ_show_temp_1;
789 	ssize_t (*show_freq)(struct device *, struct device_attribute *,
790 			     char *) = occ_show_freq_1;
791 	ssize_t (*show_power)(struct device *, struct device_attribute *,
792 			      char *) = occ_show_power_1;
793 	ssize_t (*show_caps)(struct device *, struct device_attribute *,
794 			     char *) = occ_show_caps_1_2;
795 
796 	switch (sensors->temp.version) {
797 	case 1:
798 		num_attrs += (sensors->temp.num_sensors * 2);
799 		break;
800 	case 2:
801 		num_attrs += (sensors->temp.num_sensors * 4);
802 		show_temp = occ_show_temp_2;
803 		break;
804 	case 0x10:
805 		num_attrs += (sensors->temp.num_sensors * 5);
806 		show_temp = occ_show_temp_10;
807 		break;
808 	default:
809 		sensors->temp.num_sensors = 0;
810 	}
811 
812 	switch (sensors->freq.version) {
813 	case 2:
814 		show_freq = occ_show_freq_2;
815 		fallthrough;
816 	case 1:
817 		num_attrs += (sensors->freq.num_sensors * 2);
818 		break;
819 	default:
820 		sensors->freq.num_sensors = 0;
821 	}
822 
823 	switch (sensors->power.version) {
824 	case 2:
825 		show_power = occ_show_power_2;
826 		fallthrough;
827 	case 1:
828 		num_attrs += (sensors->power.num_sensors * 4);
829 		break;
830 	case 0xA0:
831 		num_attrs += (sensors->power.num_sensors * 16);
832 		show_power = occ_show_power_a0;
833 		break;
834 	default:
835 		sensors->power.num_sensors = 0;
836 	}
837 
838 	switch (sensors->caps.version) {
839 	case 1:
840 		num_attrs += (sensors->caps.num_sensors * 7);
841 		break;
842 	case 3:
843 		show_caps = occ_show_caps_3;
844 		fallthrough;
845 	case 2:
846 		num_attrs += (sensors->caps.num_sensors * 8);
847 		break;
848 	default:
849 		sensors->caps.num_sensors = 0;
850 	}
851 
852 	switch (sensors->extended.version) {
853 	case 1:
854 		num_attrs += (sensors->extended.num_sensors * 3);
855 		break;
856 	default:
857 		sensors->extended.num_sensors = 0;
858 	}
859 
860 	occ->attrs = devm_kzalloc(dev, sizeof(*occ->attrs) * num_attrs,
861 				  GFP_KERNEL);
862 	if (!occ->attrs)
863 		return -ENOMEM;
864 
865 	/* null-terminated list */
866 	occ->group.attrs = devm_kzalloc(dev, sizeof(*occ->group.attrs) *
867 					num_attrs + 1, GFP_KERNEL);
868 	if (!occ->group.attrs)
869 		return -ENOMEM;
870 
871 	attr = occ->attrs;
872 
873 	for (i = 0; i < sensors->temp.num_sensors; ++i) {
874 		s = i + 1;
875 		temp = ((struct temp_sensor_2 *)sensors->temp.data) + i;
876 
877 		snprintf(attr->name, sizeof(attr->name), "temp%d_label", s);
878 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_temp, NULL,
879 					     0, i);
880 		attr++;
881 
882 		if (sensors->temp.version == 2 &&
883 		    temp->fru_type == OCC_FRU_TYPE_VRM) {
884 			snprintf(attr->name, sizeof(attr->name),
885 				 "temp%d_alarm", s);
886 		} else {
887 			snprintf(attr->name, sizeof(attr->name),
888 				 "temp%d_input", s);
889 		}
890 
891 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_temp, NULL,
892 					     1, i);
893 		attr++;
894 
895 		if (sensors->temp.version > 1) {
896 			snprintf(attr->name, sizeof(attr->name),
897 				 "temp%d_fru_type", s);
898 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
899 						     show_temp, NULL, 2, i);
900 			attr++;
901 
902 			snprintf(attr->name, sizeof(attr->name),
903 				 "temp%d_fault", s);
904 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
905 						     show_temp, NULL, 3, i);
906 			attr++;
907 
908 			if (sensors->temp.version == 0x10) {
909 				snprintf(attr->name, sizeof(attr->name),
910 					 "temp%d_max", s);
911 				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
912 							     show_temp, NULL,
913 							     4, i);
914 				attr++;
915 			}
916 		}
917 	}
918 
919 	for (i = 0; i < sensors->freq.num_sensors; ++i) {
920 		s = i + 1;
921 
922 		snprintf(attr->name, sizeof(attr->name), "freq%d_label", s);
923 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_freq, NULL,
924 					     0, i);
925 		attr++;
926 
927 		snprintf(attr->name, sizeof(attr->name), "freq%d_input", s);
928 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_freq, NULL,
929 					     1, i);
930 		attr++;
931 	}
932 
933 	if (sensors->power.version == 0xA0) {
934 		/*
935 		 * Special case for many-attribute power sensor. Split it into
936 		 * a sensor number per power type, emulating several sensors.
937 		 */
938 		for (i = 0; i < sensors->power.num_sensors; ++i) {
939 			unsigned int j;
940 			unsigned int nr = 0;
941 
942 			s = (i * 4) + 1;
943 
944 			for (j = 0; j < 4; ++j) {
945 				snprintf(attr->name, sizeof(attr->name),
946 					 "power%d_label", s);
947 				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
948 							     show_power, NULL,
949 							     nr++, i);
950 				attr++;
951 
952 				snprintf(attr->name, sizeof(attr->name),
953 					 "power%d_average", s);
954 				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
955 							     show_power, NULL,
956 							     nr++, i);
957 				attr++;
958 
959 				snprintf(attr->name, sizeof(attr->name),
960 					 "power%d_average_interval", s);
961 				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
962 							     show_power, NULL,
963 							     nr++, i);
964 				attr++;
965 
966 				snprintf(attr->name, sizeof(attr->name),
967 					 "power%d_input", s);
968 				attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
969 							     show_power, NULL,
970 							     nr++, i);
971 				attr++;
972 
973 				s++;
974 			}
975 		}
976 
977 		s = (sensors->power.num_sensors * 4) + 1;
978 	} else {
979 		for (i = 0; i < sensors->power.num_sensors; ++i) {
980 			s = i + 1;
981 
982 			snprintf(attr->name, sizeof(attr->name),
983 				 "power%d_label", s);
984 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
985 						     show_power, NULL, 0, i);
986 			attr++;
987 
988 			snprintf(attr->name, sizeof(attr->name),
989 				 "power%d_average", s);
990 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
991 						     show_power, NULL, 1, i);
992 			attr++;
993 
994 			snprintf(attr->name, sizeof(attr->name),
995 				 "power%d_average_interval", s);
996 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
997 						     show_power, NULL, 2, i);
998 			attr++;
999 
1000 			snprintf(attr->name, sizeof(attr->name),
1001 				 "power%d_input", s);
1002 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
1003 						     show_power, NULL, 3, i);
1004 			attr++;
1005 		}
1006 
1007 		s = sensors->power.num_sensors + 1;
1008 	}
1009 
1010 	if (sensors->caps.num_sensors >= 1) {
1011 		snprintf(attr->name, sizeof(attr->name), "power%d_label", s);
1012 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
1013 					     0, 0);
1014 		attr++;
1015 
1016 		snprintf(attr->name, sizeof(attr->name), "power%d_cap", s);
1017 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
1018 					     1, 0);
1019 		attr++;
1020 
1021 		snprintf(attr->name, sizeof(attr->name), "power%d_input", s);
1022 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
1023 					     2, 0);
1024 		attr++;
1025 
1026 		snprintf(attr->name, sizeof(attr->name),
1027 			 "power%d_cap_not_redundant", s);
1028 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
1029 					     3, 0);
1030 		attr++;
1031 
1032 		snprintf(attr->name, sizeof(attr->name), "power%d_cap_max", s);
1033 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
1034 					     4, 0);
1035 		attr++;
1036 
1037 		snprintf(attr->name, sizeof(attr->name), "power%d_cap_min", s);
1038 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444, show_caps, NULL,
1039 					     5, 0);
1040 		attr++;
1041 
1042 		snprintf(attr->name, sizeof(attr->name), "power%d_cap_user",
1043 			 s);
1044 		attr->sensor = OCC_INIT_ATTR(attr->name, 0644, show_caps,
1045 					     occ_store_caps_user, 6, 0);
1046 		attr++;
1047 
1048 		if (sensors->caps.version > 1) {
1049 			snprintf(attr->name, sizeof(attr->name),
1050 				 "power%d_cap_user_source", s);
1051 			attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
1052 						     show_caps, NULL, 7, 0);
1053 			attr++;
1054 		}
1055 	}
1056 
1057 	for (i = 0; i < sensors->extended.num_sensors; ++i) {
1058 		s = i + 1;
1059 
1060 		snprintf(attr->name, sizeof(attr->name), "extn%d_label", s);
1061 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
1062 					     occ_show_extended, NULL, 0, i);
1063 		attr++;
1064 
1065 		snprintf(attr->name, sizeof(attr->name), "extn%d_flags", s);
1066 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
1067 					     occ_show_extended, NULL, 1, i);
1068 		attr++;
1069 
1070 		snprintf(attr->name, sizeof(attr->name), "extn%d_input", s);
1071 		attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
1072 					     occ_show_extended, NULL, 2, i);
1073 		attr++;
1074 	}
1075 
1076 	/* put the sensors in the group */
1077 	for (i = 0; i < num_attrs; ++i) {
1078 		sysfs_attr_init(&occ->attrs[i].sensor.dev_attr.attr);
1079 		occ->group.attrs[i] = &occ->attrs[i].sensor.dev_attr.attr;
1080 	}
1081 
1082 	return 0;
1083 }
1084 
1085 /* only need to do this once at startup, as OCC won't change sensors on us */
1086 static void occ_parse_poll_response(struct occ *occ)
1087 {
1088 	unsigned int i, old_offset, offset = 0, size = 0;
1089 	struct occ_sensor *sensor;
1090 	struct occ_sensors *sensors = &occ->sensors;
1091 	struct occ_response *resp = &occ->resp;
1092 	struct occ_poll_response *poll =
1093 		(struct occ_poll_response *)&resp->data[0];
1094 	struct occ_poll_response_header *header = &poll->header;
1095 	struct occ_sensor_data_block *block = &poll->block;
1096 
1097 	dev_info(occ->bus_dev, "OCC found, code level: %.16s\n",
1098 		 header->occ_code_level);
1099 
1100 	for (i = 0; i < header->num_sensor_data_blocks; ++i) {
1101 		block = (struct occ_sensor_data_block *)((u8 *)block + offset);
1102 		old_offset = offset;
1103 		offset = (block->header.num_sensors *
1104 			  block->header.sensor_length) + sizeof(block->header);
1105 		size += offset;
1106 
1107 		/* validate all the length/size fields */
1108 		if ((size + sizeof(*header)) >= OCC_RESP_DATA_BYTES) {
1109 			dev_warn(occ->bus_dev, "exceeded response buffer\n");
1110 			return;
1111 		}
1112 
1113 		dev_dbg(occ->bus_dev, " %04x..%04x: %.4s (%d sensors)\n",
1114 			old_offset, offset - 1, block->header.eye_catcher,
1115 			block->header.num_sensors);
1116 
1117 		/* match sensor block type */
1118 		if (strncmp(block->header.eye_catcher, "TEMP", 4) == 0)
1119 			sensor = &sensors->temp;
1120 		else if (strncmp(block->header.eye_catcher, "FREQ", 4) == 0)
1121 			sensor = &sensors->freq;
1122 		else if (strncmp(block->header.eye_catcher, "POWR", 4) == 0)
1123 			sensor = &sensors->power;
1124 		else if (strncmp(block->header.eye_catcher, "CAPS", 4) == 0)
1125 			sensor = &sensors->caps;
1126 		else if (strncmp(block->header.eye_catcher, "EXTN", 4) == 0)
1127 			sensor = &sensors->extended;
1128 		else {
1129 			dev_warn(occ->bus_dev, "sensor not supported %.4s\n",
1130 				 block->header.eye_catcher);
1131 			continue;
1132 		}
1133 
1134 		sensor->num_sensors = block->header.num_sensors;
1135 		sensor->version = block->header.sensor_format;
1136 		sensor->data = &block->data;
1137 	}
1138 
1139 	dev_dbg(occ->bus_dev, "Max resp size: %u+%zd=%zd\n", size,
1140 		sizeof(*header), size + sizeof(*header));
1141 }
1142 
1143 int occ_setup(struct occ *occ, const char *name)
1144 {
1145 	int rc;
1146 
1147 	/* start with 1 to avoid false match with zero-initialized SRAM buffer */
1148 	occ->seq_no = 1;
1149 	mutex_init(&occ->lock);
1150 	occ->groups[0] = &occ->group;
1151 
1152 	/* no need to lock */
1153 	rc = occ_poll(occ);
1154 	if (rc == -ESHUTDOWN) {
1155 		dev_info(occ->bus_dev, "host is not ready\n");
1156 		return rc;
1157 	} else if (rc < 0) {
1158 		dev_err(occ->bus_dev,
1159 			"failed to get OCC poll response=%02x: %d\n",
1160 			occ->resp.return_status, rc);
1161 		return rc;
1162 	}
1163 
1164 	occ->next_update = jiffies + OCC_UPDATE_FREQUENCY;
1165 	occ_parse_poll_response(occ);
1166 
1167 	rc = occ_setup_sensor_attrs(occ);
1168 	if (rc) {
1169 		dev_err(occ->bus_dev, "failed to setup sensor attrs: %d\n",
1170 			rc);
1171 		return rc;
1172 	}
1173 
1174 	occ->hwmon = devm_hwmon_device_register_with_groups(occ->bus_dev, name,
1175 							    occ, occ->groups);
1176 	if (IS_ERR(occ->hwmon)) {
1177 		rc = PTR_ERR(occ->hwmon);
1178 		dev_err(occ->bus_dev, "failed to register hwmon device: %d\n",
1179 			rc);
1180 		return rc;
1181 	}
1182 
1183 	rc = occ_setup_sysfs(occ);
1184 	if (rc)
1185 		dev_err(occ->bus_dev, "failed to setup sysfs: %d\n", rc);
1186 
1187 	return rc;
1188 }
1189 EXPORT_SYMBOL_GPL(occ_setup);
1190 
1191 MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>");
1192 MODULE_DESCRIPTION("Common OCC hwmon code");
1193 MODULE_LICENSE("GPL");
1194