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 */
36enum 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 */
52static 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
59static 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
73struct 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
84struct sensor_group_data {
85	struct mutex mutex;
86	u32 gid;
87	bool enable;
88};
89
90struct 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
97static 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
123static 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
132static 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
163static 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
172static 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
183static 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 = scnprintf(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 += scnprintf(sdata->label + n,
203				      sizeof(sdata->label) - n, " %d",
204				      cpuid);
205		else
206			n += scnprintf(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 += scnprintf(sdata->label + n, sizeof(sdata->label) - n,
215			      " %d", id & 0xffff);
216}
217
218static 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	memcpy(buf, hash_pos + 1, copy_len);
238
239	err = kstrtou32(buf, 10, index);
240	if (err)
241		return err;
242
243	strscpy(attr, dash_pos + 1, MAX_ATTR_LEN);
244
245	return 0;
246}
247
248static 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 */
273static 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
291static 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
317static 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
334static 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;
382out:
383	of_node_put(groups);
384	return ret;
385}
386
387static 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
432static 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_property_present(np, "sensor-data-min"))
460			sensor_groups[type].attr_count++;
461		if (of_property_present(np, "sensor-data-max"))
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
483static 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
506static 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
526static 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
536static 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 */
552static 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
662static 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
692static const struct platform_device_id opal_sensor_driver_ids[] = {
693	{
694		.name = "opal-sensor",
695	},
696	{ }
697};
698MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids);
699
700static const struct of_device_id opal_sensor_match[] = {
701	{ .compatible	= "ibm,opal-sensor" },
702	{ },
703};
704MODULE_DEVICE_TABLE(of, opal_sensor_match);
705
706static 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
715module_platform_driver(ibmpowernv_driver);
716
717MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
718MODULE_DESCRIPTION("IBM POWERNV platform sensors");
719MODULE_LICENSE("GPL");
720