xref: /linux/drivers/hwmon/ibmpowernv.c (revision 22d55f02b8922a097cd4be1e2f131dfa7ef65901)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * IBM PowerNV platform sensors for temperature/fan/voltage/power
4  * Copyright (C) 2014 IBM
5  */
6 
7 #define DRVNAME		"ibmpowernv"
8 #define pr_fmt(fmt)	DRVNAME ": " fmt
9 
10 #include <linux/init.h>
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/hwmon.h>
14 #include <linux/hwmon-sysfs.h>
15 #include <linux/of.h>
16 #include <linux/slab.h>
17 
18 #include <linux/platform_device.h>
19 #include <asm/opal.h>
20 #include <linux/err.h>
21 #include <asm/cputhreads.h>
22 #include <asm/smp.h>
23 
24 #define MAX_ATTR_LEN	32
25 #define MAX_LABEL_LEN	64
26 
27 /* Sensor suffix name from DT */
28 #define DT_FAULT_ATTR_SUFFIX		"faulted"
29 #define DT_DATA_ATTR_SUFFIX		"data"
30 #define DT_THRESHOLD_ATTR_SUFFIX	"thrs"
31 
32 /*
33  * Enumerates all the types of sensors in the POWERNV platform and does index
34  * into 'struct sensor_group'
35  */
36 enum sensors {
37 	FAN,
38 	TEMP,
39 	POWER_SUPPLY,
40 	POWER_INPUT,
41 	CURRENT,
42 	ENERGY,
43 	MAX_SENSOR_TYPE,
44 };
45 
46 #define INVALID_INDEX (-1U)
47 
48 /*
49  * 'compatible' string properties for sensor types as defined in old
50  * PowerNV firmware (skiboot). These are ordered as 'enum sensors'.
51  */
52 static const char * const legacy_compatibles[] = {
53 	"ibm,opal-sensor-cooling-fan",
54 	"ibm,opal-sensor-amb-temp",
55 	"ibm,opal-sensor-power-supply",
56 	"ibm,opal-sensor-power"
57 };
58 
59 static struct sensor_group {
60 	const char *name; /* matches property 'sensor-type' */
61 	struct attribute_group group;
62 	u32 attr_count;
63 	u32 hwmon_index;
64 } sensor_groups[] = {
65 	{ "fan"   },
66 	{ "temp"  },
67 	{ "in"    },
68 	{ "power" },
69 	{ "curr"  },
70 	{ "energy" },
71 };
72 
73 struct sensor_data {
74 	u32 id; /* An opaque id of the firmware for each sensor */
75 	u32 hwmon_index;
76 	u32 opal_index;
77 	enum sensors type;
78 	char label[MAX_LABEL_LEN];
79 	char name[MAX_ATTR_LEN];
80 	struct device_attribute dev_attr;
81 	struct sensor_group_data *sgrp_data;
82 };
83 
84 struct sensor_group_data {
85 	struct mutex mutex;
86 	u32 gid;
87 	bool enable;
88 };
89 
90 struct platform_data {
91 	const struct attribute_group *attr_groups[MAX_SENSOR_TYPE + 1];
92 	struct sensor_group_data *sgrp_data;
93 	u32 sensors_count; /* Total count of sensors from each group */
94 	u32 nr_sensor_groups; /* Total number of sensor groups */
95 };
96 
97 static ssize_t show_sensor(struct device *dev, struct device_attribute *devattr,
98 			   char *buf)
99 {
100 	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
101 						 dev_attr);
102 	ssize_t ret;
103 	u64 x;
104 
105 	if (sdata->sgrp_data && !sdata->sgrp_data->enable)
106 		return -ENODATA;
107 
108 	ret =  opal_get_sensor_data_u64(sdata->id, &x);
109 
110 	if (ret)
111 		return ret;
112 
113 	/* Convert temperature to milli-degrees */
114 	if (sdata->type == TEMP)
115 		x *= 1000;
116 	/* Convert power to micro-watts */
117 	else if (sdata->type == POWER_INPUT)
118 		x *= 1000000;
119 
120 	return sprintf(buf, "%llu\n", x);
121 }
122 
123 static ssize_t show_enable(struct device *dev,
124 			   struct device_attribute *devattr, char *buf)
125 {
126 	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
127 						 dev_attr);
128 
129 	return sprintf(buf, "%u\n", sdata->sgrp_data->enable);
130 }
131 
132 static ssize_t store_enable(struct device *dev,
133 			    struct device_attribute *devattr,
134 			    const char *buf, size_t count)
135 {
136 	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
137 						 dev_attr);
138 	struct sensor_group_data *sgrp_data = sdata->sgrp_data;
139 	int ret;
140 	bool data;
141 
142 	ret = kstrtobool(buf, &data);
143 	if (ret)
144 		return ret;
145 
146 	ret = mutex_lock_interruptible(&sgrp_data->mutex);
147 	if (ret)
148 		return ret;
149 
150 	if (data != sgrp_data->enable) {
151 		ret =  sensor_group_enable(sgrp_data->gid, data);
152 		if (!ret)
153 			sgrp_data->enable = data;
154 	}
155 
156 	if (!ret)
157 		ret = count;
158 
159 	mutex_unlock(&sgrp_data->mutex);
160 	return ret;
161 }
162 
163 static ssize_t show_label(struct device *dev, struct device_attribute *devattr,
164 			  char *buf)
165 {
166 	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
167 						 dev_attr);
168 
169 	return sprintf(buf, "%s\n", sdata->label);
170 }
171 
172 static int get_logical_cpu(int hwcpu)
173 {
174 	int cpu;
175 
176 	for_each_possible_cpu(cpu)
177 		if (get_hard_smp_processor_id(cpu) == hwcpu)
178 			return cpu;
179 
180 	return -ENOENT;
181 }
182 
183 static void make_sensor_label(struct device_node *np,
184 			      struct sensor_data *sdata, const char *label)
185 {
186 	u32 id;
187 	size_t n;
188 
189 	n = snprintf(sdata->label, sizeof(sdata->label), "%s", label);
190 
191 	/*
192 	 * Core temp pretty print
193 	 */
194 	if (!of_property_read_u32(np, "ibm,pir", &id)) {
195 		int cpuid = get_logical_cpu(id);
196 
197 		if (cpuid >= 0)
198 			/*
199 			 * The digital thermal sensors are associated
200 			 * with a core.
201 			 */
202 			n += snprintf(sdata->label + n,
203 				      sizeof(sdata->label) - n, " %d",
204 				      cpuid);
205 		else
206 			n += snprintf(sdata->label + n,
207 				      sizeof(sdata->label) - n, " phy%d", id);
208 	}
209 
210 	/*
211 	 * Membuffer pretty print
212 	 */
213 	if (!of_property_read_u32(np, "ibm,chip-id", &id))
214 		n += snprintf(sdata->label + n, sizeof(sdata->label) - n,
215 			      " %d", id & 0xffff);
216 }
217 
218 static int get_sensor_index_attr(const char *name, u32 *index, char *attr)
219 {
220 	char *hash_pos = strchr(name, '#');
221 	char buf[8] = { 0 };
222 	char *dash_pos;
223 	u32 copy_len;
224 	int err;
225 
226 	if (!hash_pos)
227 		return -EINVAL;
228 
229 	dash_pos = strchr(hash_pos, '-');
230 	if (!dash_pos)
231 		return -EINVAL;
232 
233 	copy_len = dash_pos - hash_pos - 1;
234 	if (copy_len >= sizeof(buf))
235 		return -EINVAL;
236 
237 	strncpy(buf, hash_pos + 1, copy_len);
238 
239 	err = kstrtou32(buf, 10, index);
240 	if (err)
241 		return err;
242 
243 	strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);
244 
245 	return 0;
246 }
247 
248 static const char *convert_opal_attr_name(enum sensors type,
249 					  const char *opal_attr)
250 {
251 	const char *attr_name = NULL;
252 
253 	if (!strcmp(opal_attr, DT_FAULT_ATTR_SUFFIX)) {
254 		attr_name = "fault";
255 	} else if (!strcmp(opal_attr, DT_DATA_ATTR_SUFFIX)) {
256 		attr_name = "input";
257 	} else if (!strcmp(opal_attr, DT_THRESHOLD_ATTR_SUFFIX)) {
258 		if (type == TEMP)
259 			attr_name = "max";
260 		else if (type == FAN)
261 			attr_name = "min";
262 	}
263 
264 	return attr_name;
265 }
266 
267 /*
268  * This function translates the DT node name into the 'hwmon' attribute name.
269  * IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
270  * which need to be mapped as fan2_input, temp1_max respectively before
271  * populating them inside hwmon device class.
272  */
273 static const char *parse_opal_node_name(const char *node_name,
274 					enum sensors type, u32 *index)
275 {
276 	char attr_suffix[MAX_ATTR_LEN];
277 	const char *attr_name;
278 	int err;
279 
280 	err = get_sensor_index_attr(node_name, index, attr_suffix);
281 	if (err)
282 		return ERR_PTR(err);
283 
284 	attr_name = convert_opal_attr_name(type, attr_suffix);
285 	if (!attr_name)
286 		return ERR_PTR(-ENOENT);
287 
288 	return attr_name;
289 }
290 
291 static int get_sensor_type(struct device_node *np)
292 {
293 	enum sensors type;
294 	const char *str;
295 
296 	for (type = 0; type < ARRAY_SIZE(legacy_compatibles); type++) {
297 		if (of_device_is_compatible(np, legacy_compatibles[type]))
298 			return type;
299 	}
300 
301 	/*
302 	 * Let's check if we have a newer device tree
303 	 */
304 	if (!of_device_is_compatible(np, "ibm,opal-sensor"))
305 		return MAX_SENSOR_TYPE;
306 
307 	if (of_property_read_string(np, "sensor-type", &str))
308 		return MAX_SENSOR_TYPE;
309 
310 	for (type = 0; type < MAX_SENSOR_TYPE; type++)
311 		if (!strcmp(str, sensor_groups[type].name))
312 			return type;
313 
314 	return MAX_SENSOR_TYPE;
315 }
316 
317 static u32 get_sensor_hwmon_index(struct sensor_data *sdata,
318 				  struct sensor_data *sdata_table, int count)
319 {
320 	int i;
321 
322 	/*
323 	 * We don't use the OPAL index on newer device trees
324 	 */
325 	if (sdata->opal_index != INVALID_INDEX) {
326 		for (i = 0; i < count; i++)
327 			if (sdata_table[i].opal_index == sdata->opal_index &&
328 			    sdata_table[i].type == sdata->type)
329 				return sdata_table[i].hwmon_index;
330 	}
331 	return ++sensor_groups[sdata->type].hwmon_index;
332 }
333 
334 static int init_sensor_group_data(struct platform_device *pdev,
335 				  struct platform_data *pdata)
336 {
337 	struct sensor_group_data *sgrp_data;
338 	struct device_node *groups, *sgrp;
339 	int count = 0, ret = 0;
340 	enum sensors type;
341 
342 	groups = of_find_compatible_node(NULL, NULL, "ibm,opal-sensor-group");
343 	if (!groups)
344 		return ret;
345 
346 	for_each_child_of_node(groups, sgrp) {
347 		type = get_sensor_type(sgrp);
348 		if (type != MAX_SENSOR_TYPE)
349 			pdata->nr_sensor_groups++;
350 	}
351 
352 	if (!pdata->nr_sensor_groups)
353 		goto out;
354 
355 	sgrp_data = devm_kcalloc(&pdev->dev, pdata->nr_sensor_groups,
356 				 sizeof(*sgrp_data), GFP_KERNEL);
357 	if (!sgrp_data) {
358 		ret = -ENOMEM;
359 		goto out;
360 	}
361 
362 	for_each_child_of_node(groups, sgrp) {
363 		u32 gid;
364 
365 		type = get_sensor_type(sgrp);
366 		if (type == MAX_SENSOR_TYPE)
367 			continue;
368 
369 		if (of_property_read_u32(sgrp, "sensor-group-id", &gid))
370 			continue;
371 
372 		if (of_count_phandle_with_args(sgrp, "sensors", NULL) <= 0)
373 			continue;
374 
375 		sensor_groups[type].attr_count++;
376 		sgrp_data[count].gid = gid;
377 		mutex_init(&sgrp_data[count].mutex);
378 		sgrp_data[count++].enable = false;
379 	}
380 
381 	pdata->sgrp_data = sgrp_data;
382 out:
383 	of_node_put(groups);
384 	return ret;
385 }
386 
387 static struct sensor_group_data *get_sensor_group(struct platform_data *pdata,
388 						  struct device_node *node,
389 						  enum sensors gtype)
390 {
391 	struct sensor_group_data *sgrp_data = pdata->sgrp_data;
392 	struct device_node *groups, *sgrp;
393 
394 	groups = of_find_compatible_node(NULL, NULL, "ibm,opal-sensor-group");
395 	if (!groups)
396 		return NULL;
397 
398 	for_each_child_of_node(groups, sgrp) {
399 		struct of_phandle_iterator it;
400 		u32 gid;
401 		int rc, i;
402 		enum sensors type;
403 
404 		type = get_sensor_type(sgrp);
405 		if (type != gtype)
406 			continue;
407 
408 		if (of_property_read_u32(sgrp, "sensor-group-id", &gid))
409 			continue;
410 
411 		of_for_each_phandle(&it, rc, sgrp, "sensors", NULL, 0)
412 			if (it.phandle == node->phandle) {
413 				of_node_put(it.node);
414 				break;
415 			}
416 
417 		if (rc)
418 			continue;
419 
420 		for (i = 0; i < pdata->nr_sensor_groups; i++)
421 			if (gid == sgrp_data[i].gid) {
422 				of_node_put(sgrp);
423 				of_node_put(groups);
424 				return &sgrp_data[i];
425 			}
426 	}
427 
428 	of_node_put(groups);
429 	return NULL;
430 }
431 
432 static int populate_attr_groups(struct platform_device *pdev)
433 {
434 	struct platform_data *pdata = platform_get_drvdata(pdev);
435 	const struct attribute_group **pgroups = pdata->attr_groups;
436 	struct device_node *opal, *np;
437 	enum sensors type;
438 	int ret;
439 
440 	ret = init_sensor_group_data(pdev, pdata);
441 	if (ret)
442 		return ret;
443 
444 	opal = of_find_node_by_path("/ibm,opal/sensors");
445 	for_each_child_of_node(opal, np) {
446 		const char *label;
447 
448 		type = get_sensor_type(np);
449 		if (type == MAX_SENSOR_TYPE)
450 			continue;
451 
452 		sensor_groups[type].attr_count++;
453 
454 		/*
455 		 * add attributes for labels, min and max
456 		 */
457 		if (!of_property_read_string(np, "label", &label))
458 			sensor_groups[type].attr_count++;
459 		if (of_find_property(np, "sensor-data-min", NULL))
460 			sensor_groups[type].attr_count++;
461 		if (of_find_property(np, "sensor-data-max", NULL))
462 			sensor_groups[type].attr_count++;
463 	}
464 
465 	of_node_put(opal);
466 
467 	for (type = 0; type < MAX_SENSOR_TYPE; type++) {
468 		sensor_groups[type].group.attrs = devm_kcalloc(&pdev->dev,
469 					sensor_groups[type].attr_count + 1,
470 					sizeof(struct attribute *),
471 					GFP_KERNEL);
472 		if (!sensor_groups[type].group.attrs)
473 			return -ENOMEM;
474 
475 		pgroups[type] = &sensor_groups[type].group;
476 		pdata->sensors_count += sensor_groups[type].attr_count;
477 		sensor_groups[type].attr_count = 0;
478 	}
479 
480 	return 0;
481 }
482 
483 static void create_hwmon_attr(struct sensor_data *sdata, const char *attr_name,
484 			      ssize_t (*show)(struct device *dev,
485 					      struct device_attribute *attr,
486 					      char *buf),
487 			    ssize_t (*store)(struct device *dev,
488 					     struct device_attribute *attr,
489 					     const char *buf, size_t count))
490 {
491 	snprintf(sdata->name, MAX_ATTR_LEN, "%s%d_%s",
492 		 sensor_groups[sdata->type].name, sdata->hwmon_index,
493 		 attr_name);
494 
495 	sysfs_attr_init(&sdata->dev_attr.attr);
496 	sdata->dev_attr.attr.name = sdata->name;
497 	sdata->dev_attr.show = show;
498 	if (store) {
499 		sdata->dev_attr.store = store;
500 		sdata->dev_attr.attr.mode = 0664;
501 	} else {
502 		sdata->dev_attr.attr.mode = 0444;
503 	}
504 }
505 
506 static void populate_sensor(struct sensor_data *sdata, int od, int hd, int sid,
507 			    const char *attr_name, enum sensors type,
508 			    const struct attribute_group *pgroup,
509 			    struct sensor_group_data *sgrp_data,
510 			    ssize_t (*show)(struct device *dev,
511 					    struct device_attribute *attr,
512 					    char *buf),
513 			    ssize_t (*store)(struct device *dev,
514 					     struct device_attribute *attr,
515 					     const char *buf, size_t count))
516 {
517 	sdata->id = sid;
518 	sdata->type = type;
519 	sdata->opal_index = od;
520 	sdata->hwmon_index = hd;
521 	create_hwmon_attr(sdata, attr_name, show, store);
522 	pgroup->attrs[sensor_groups[type].attr_count++] = &sdata->dev_attr.attr;
523 	sdata->sgrp_data = sgrp_data;
524 }
525 
526 static char *get_max_attr(enum sensors type)
527 {
528 	switch (type) {
529 	case POWER_INPUT:
530 		return "input_highest";
531 	default:
532 		return "highest";
533 	}
534 }
535 
536 static char *get_min_attr(enum sensors type)
537 {
538 	switch (type) {
539 	case POWER_INPUT:
540 		return "input_lowest";
541 	default:
542 		return "lowest";
543 	}
544 }
545 
546 /*
547  * Iterate through the device tree for each child of 'sensors' node, create
548  * a sysfs attribute file, the file is named by translating the DT node name
549  * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
550  * etc..
551  */
552 static int create_device_attrs(struct platform_device *pdev)
553 {
554 	struct platform_data *pdata = platform_get_drvdata(pdev);
555 	const struct attribute_group **pgroups = pdata->attr_groups;
556 	struct device_node *opal, *np;
557 	struct sensor_data *sdata;
558 	u32 count = 0;
559 	u32 group_attr_id[MAX_SENSOR_TYPE] = {0};
560 
561 	sdata = devm_kcalloc(&pdev->dev,
562 			     pdata->sensors_count, sizeof(*sdata),
563 			     GFP_KERNEL);
564 	if (!sdata)
565 		return -ENOMEM;
566 
567 	opal = of_find_node_by_path("/ibm,opal/sensors");
568 	for_each_child_of_node(opal, np) {
569 		struct sensor_group_data *sgrp_data;
570 		const char *attr_name;
571 		u32 opal_index, hw_id;
572 		u32 sensor_id;
573 		const char *label;
574 		enum sensors type;
575 
576 		type = get_sensor_type(np);
577 		if (type == MAX_SENSOR_TYPE)
578 			continue;
579 
580 		/*
581 		 * Newer device trees use a "sensor-data" property
582 		 * name for input.
583 		 */
584 		if (of_property_read_u32(np, "sensor-id", &sensor_id) &&
585 		    of_property_read_u32(np, "sensor-data", &sensor_id)) {
586 			dev_info(&pdev->dev,
587 				 "'sensor-id' missing in the node '%pOFn'\n",
588 				 np);
589 			continue;
590 		}
591 
592 		sdata[count].id = sensor_id;
593 		sdata[count].type = type;
594 
595 		/*
596 		 * If we can not parse the node name, it means we are
597 		 * running on a newer device tree. We can just forget
598 		 * about the OPAL index and use a defaut value for the
599 		 * hwmon attribute name
600 		 */
601 		attr_name = parse_opal_node_name(np->name, type, &opal_index);
602 		if (IS_ERR(attr_name)) {
603 			attr_name = "input";
604 			opal_index = INVALID_INDEX;
605 		}
606 
607 		hw_id = get_sensor_hwmon_index(&sdata[count], sdata, count);
608 		sgrp_data = get_sensor_group(pdata, np, type);
609 		populate_sensor(&sdata[count], opal_index, hw_id, sensor_id,
610 				attr_name, type, pgroups[type], sgrp_data,
611 				show_sensor, NULL);
612 		count++;
613 
614 		if (!of_property_read_string(np, "label", &label)) {
615 			/*
616 			 * For the label attribute, we can reuse the
617 			 * "properties" of the previous "input"
618 			 * attribute. They are related to the same
619 			 * sensor.
620 			 */
621 
622 			make_sensor_label(np, &sdata[count], label);
623 			populate_sensor(&sdata[count], opal_index, hw_id,
624 					sensor_id, "label", type, pgroups[type],
625 					NULL, show_label, NULL);
626 			count++;
627 		}
628 
629 		if (!of_property_read_u32(np, "sensor-data-max", &sensor_id)) {
630 			attr_name = get_max_attr(type);
631 			populate_sensor(&sdata[count], opal_index, hw_id,
632 					sensor_id, attr_name, type,
633 					pgroups[type], sgrp_data, show_sensor,
634 					NULL);
635 			count++;
636 		}
637 
638 		if (!of_property_read_u32(np, "sensor-data-min", &sensor_id)) {
639 			attr_name = get_min_attr(type);
640 			populate_sensor(&sdata[count], opal_index, hw_id,
641 					sensor_id, attr_name, type,
642 					pgroups[type], sgrp_data, show_sensor,
643 					NULL);
644 			count++;
645 		}
646 
647 		if (sgrp_data && !sgrp_data->enable) {
648 			sgrp_data->enable = true;
649 			hw_id = ++group_attr_id[type];
650 			populate_sensor(&sdata[count], opal_index, hw_id,
651 					sgrp_data->gid, "enable", type,
652 					pgroups[type], sgrp_data, show_enable,
653 					store_enable);
654 			count++;
655 		}
656 	}
657 
658 	of_node_put(opal);
659 	return 0;
660 }
661 
662 static int ibmpowernv_probe(struct platform_device *pdev)
663 {
664 	struct platform_data *pdata;
665 	struct device *hwmon_dev;
666 	int err;
667 
668 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
669 	if (!pdata)
670 		return -ENOMEM;
671 
672 	platform_set_drvdata(pdev, pdata);
673 	pdata->sensors_count = 0;
674 	pdata->nr_sensor_groups = 0;
675 	err = populate_attr_groups(pdev);
676 	if (err)
677 		return err;
678 
679 	/* Create sysfs attribute data for each sensor found in the DT */
680 	err = create_device_attrs(pdev);
681 	if (err)
682 		return err;
683 
684 	/* Finally, register with hwmon */
685 	hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
686 							   pdata,
687 							   pdata->attr_groups);
688 
689 	return PTR_ERR_OR_ZERO(hwmon_dev);
690 }
691 
692 static const struct platform_device_id opal_sensor_driver_ids[] = {
693 	{
694 		.name = "opal-sensor",
695 	},
696 	{ }
697 };
698 MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids);
699 
700 static const struct of_device_id opal_sensor_match[] = {
701 	{ .compatible	= "ibm,opal-sensor" },
702 	{ },
703 };
704 MODULE_DEVICE_TABLE(of, opal_sensor_match);
705 
706 static struct platform_driver ibmpowernv_driver = {
707 	.probe		= ibmpowernv_probe,
708 	.id_table	= opal_sensor_driver_ids,
709 	.driver		= {
710 		.name	= DRVNAME,
711 		.of_match_table	= opal_sensor_match,
712 	},
713 };
714 
715 module_platform_driver(ibmpowernv_driver);
716 
717 MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
718 MODULE_DESCRIPTION("IBM POWERNV platform sensors");
719 MODULE_LICENSE("GPL");
720