xref: /openbmc/linux/drivers/hwmon/ibmpowernv.c (revision feac8c8b)
1 /*
2  * IBM PowerNV platform sensors for temperature/fan/voltage/power
3  * Copyright (C) 2014 IBM
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program.
17  */
18 
19 #define DRVNAME		"ibmpowernv"
20 #define pr_fmt(fmt)	DRVNAME ": " fmt
21 
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/kernel.h>
25 #include <linux/hwmon.h>
26 #include <linux/hwmon-sysfs.h>
27 #include <linux/of.h>
28 #include <linux/slab.h>
29 
30 #include <linux/platform_device.h>
31 #include <asm/opal.h>
32 #include <linux/err.h>
33 #include <asm/cputhreads.h>
34 #include <asm/smp.h>
35 
36 #define MAX_ATTR_LEN	32
37 #define MAX_LABEL_LEN	64
38 
39 /* Sensor suffix name from DT */
40 #define DT_FAULT_ATTR_SUFFIX		"faulted"
41 #define DT_DATA_ATTR_SUFFIX		"data"
42 #define DT_THRESHOLD_ATTR_SUFFIX	"thrs"
43 
44 /*
45  * Enumerates all the types of sensors in the POWERNV platform and does index
46  * into 'struct sensor_group'
47  */
48 enum sensors {
49 	FAN,
50 	TEMP,
51 	POWER_SUPPLY,
52 	POWER_INPUT,
53 	CURRENT,
54 	MAX_SENSOR_TYPE,
55 };
56 
57 #define INVALID_INDEX (-1U)
58 
59 /*
60  * 'compatible' string properties for sensor types as defined in old
61  * PowerNV firmware (skiboot). These are ordered as 'enum sensors'.
62  */
63 static const char * const legacy_compatibles[] = {
64 	"ibm,opal-sensor-cooling-fan",
65 	"ibm,opal-sensor-amb-temp",
66 	"ibm,opal-sensor-power-supply",
67 	"ibm,opal-sensor-power"
68 };
69 
70 static struct sensor_group {
71 	const char *name; /* matches property 'sensor-type' */
72 	struct attribute_group group;
73 	u32 attr_count;
74 	u32 hwmon_index;
75 } sensor_groups[] = {
76 	{ "fan"   },
77 	{ "temp"  },
78 	{ "in"    },
79 	{ "power" },
80 	{ "curr"  },
81 };
82 
83 struct sensor_data {
84 	u32 id; /* An opaque id of the firmware for each sensor */
85 	u32 hwmon_index;
86 	u32 opal_index;
87 	enum sensors type;
88 	char label[MAX_LABEL_LEN];
89 	char name[MAX_ATTR_LEN];
90 	struct device_attribute dev_attr;
91 };
92 
93 struct platform_data {
94 	const struct attribute_group *attr_groups[MAX_SENSOR_TYPE + 1];
95 	u32 sensors_count; /* Total count of sensors from each group */
96 };
97 
98 static ssize_t show_sensor(struct device *dev, struct device_attribute *devattr,
99 			   char *buf)
100 {
101 	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
102 						 dev_attr);
103 	ssize_t ret;
104 	u32 x;
105 
106 	ret = opal_get_sensor_data(sdata->id, &x);
107 	if (ret)
108 		return ret;
109 
110 	/* Convert temperature to milli-degrees */
111 	if (sdata->type == TEMP)
112 		x *= 1000;
113 	/* Convert power to micro-watts */
114 	else if (sdata->type == POWER_INPUT)
115 		x *= 1000000;
116 
117 	return sprintf(buf, "%u\n", x);
118 }
119 
120 static ssize_t show_label(struct device *dev, struct device_attribute *devattr,
121 			  char *buf)
122 {
123 	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
124 						 dev_attr);
125 
126 	return sprintf(buf, "%s\n", sdata->label);
127 }
128 
129 static int __init get_logical_cpu(int hwcpu)
130 {
131 	int cpu;
132 
133 	for_each_possible_cpu(cpu)
134 		if (get_hard_smp_processor_id(cpu) == hwcpu)
135 			return cpu;
136 
137 	return -ENOENT;
138 }
139 
140 static void __init make_sensor_label(struct device_node *np,
141 				     struct sensor_data *sdata,
142 				     const char *label)
143 {
144 	u32 id;
145 	size_t n;
146 
147 	n = snprintf(sdata->label, sizeof(sdata->label), "%s", label);
148 
149 	/*
150 	 * Core temp pretty print
151 	 */
152 	if (!of_property_read_u32(np, "ibm,pir", &id)) {
153 		int cpuid = get_logical_cpu(id);
154 
155 		if (cpuid >= 0)
156 			/*
157 			 * The digital thermal sensors are associated
158 			 * with a core.
159 			 */
160 			n += snprintf(sdata->label + n,
161 				      sizeof(sdata->label) - n, " %d",
162 				      cpuid);
163 		else
164 			n += snprintf(sdata->label + n,
165 				      sizeof(sdata->label) - n, " phy%d", id);
166 	}
167 
168 	/*
169 	 * Membuffer pretty print
170 	 */
171 	if (!of_property_read_u32(np, "ibm,chip-id", &id))
172 		n += snprintf(sdata->label + n, sizeof(sdata->label) - n,
173 			      " %d", id & 0xffff);
174 }
175 
176 static int get_sensor_index_attr(const char *name, u32 *index, char *attr)
177 {
178 	char *hash_pos = strchr(name, '#');
179 	char buf[8] = { 0 };
180 	char *dash_pos;
181 	u32 copy_len;
182 	int err;
183 
184 	if (!hash_pos)
185 		return -EINVAL;
186 
187 	dash_pos = strchr(hash_pos, '-');
188 	if (!dash_pos)
189 		return -EINVAL;
190 
191 	copy_len = dash_pos - hash_pos - 1;
192 	if (copy_len >= sizeof(buf))
193 		return -EINVAL;
194 
195 	strncpy(buf, hash_pos + 1, copy_len);
196 
197 	err = kstrtou32(buf, 10, index);
198 	if (err)
199 		return err;
200 
201 	strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);
202 
203 	return 0;
204 }
205 
206 static const char *convert_opal_attr_name(enum sensors type,
207 					  const char *opal_attr)
208 {
209 	const char *attr_name = NULL;
210 
211 	if (!strcmp(opal_attr, DT_FAULT_ATTR_SUFFIX)) {
212 		attr_name = "fault";
213 	} else if (!strcmp(opal_attr, DT_DATA_ATTR_SUFFIX)) {
214 		attr_name = "input";
215 	} else if (!strcmp(opal_attr, DT_THRESHOLD_ATTR_SUFFIX)) {
216 		if (type == TEMP)
217 			attr_name = "max";
218 		else if (type == FAN)
219 			attr_name = "min";
220 	}
221 
222 	return attr_name;
223 }
224 
225 /*
226  * This function translates the DT node name into the 'hwmon' attribute name.
227  * IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
228  * which need to be mapped as fan2_input, temp1_max respectively before
229  * populating them inside hwmon device class.
230  */
231 static const char *parse_opal_node_name(const char *node_name,
232 					enum sensors type, u32 *index)
233 {
234 	char attr_suffix[MAX_ATTR_LEN];
235 	const char *attr_name;
236 	int err;
237 
238 	err = get_sensor_index_attr(node_name, index, attr_suffix);
239 	if (err)
240 		return ERR_PTR(err);
241 
242 	attr_name = convert_opal_attr_name(type, attr_suffix);
243 	if (!attr_name)
244 		return ERR_PTR(-ENOENT);
245 
246 	return attr_name;
247 }
248 
249 static int get_sensor_type(struct device_node *np)
250 {
251 	enum sensors type;
252 	const char *str;
253 
254 	for (type = 0; type < ARRAY_SIZE(legacy_compatibles); type++) {
255 		if (of_device_is_compatible(np, legacy_compatibles[type]))
256 			return type;
257 	}
258 
259 	/*
260 	 * Let's check if we have a newer device tree
261 	 */
262 	if (!of_device_is_compatible(np, "ibm,opal-sensor"))
263 		return MAX_SENSOR_TYPE;
264 
265 	if (of_property_read_string(np, "sensor-type", &str))
266 		return MAX_SENSOR_TYPE;
267 
268 	for (type = 0; type < MAX_SENSOR_TYPE; type++)
269 		if (!strcmp(str, sensor_groups[type].name))
270 			return type;
271 
272 	return MAX_SENSOR_TYPE;
273 }
274 
275 static u32 get_sensor_hwmon_index(struct sensor_data *sdata,
276 				  struct sensor_data *sdata_table, int count)
277 {
278 	int i;
279 
280 	/*
281 	 * We don't use the OPAL index on newer device trees
282 	 */
283 	if (sdata->opal_index != INVALID_INDEX) {
284 		for (i = 0; i < count; i++)
285 			if (sdata_table[i].opal_index == sdata->opal_index &&
286 			    sdata_table[i].type == sdata->type)
287 				return sdata_table[i].hwmon_index;
288 	}
289 	return ++sensor_groups[sdata->type].hwmon_index;
290 }
291 
292 static int populate_attr_groups(struct platform_device *pdev)
293 {
294 	struct platform_data *pdata = platform_get_drvdata(pdev);
295 	const struct attribute_group **pgroups = pdata->attr_groups;
296 	struct device_node *opal, *np;
297 	enum sensors type;
298 
299 	opal = of_find_node_by_path("/ibm,opal/sensors");
300 	for_each_child_of_node(opal, np) {
301 		const char *label;
302 
303 		if (np->name == NULL)
304 			continue;
305 
306 		type = get_sensor_type(np);
307 		if (type == MAX_SENSOR_TYPE)
308 			continue;
309 
310 		sensor_groups[type].attr_count++;
311 
312 		/*
313 		 * add attributes for labels, min and max
314 		 */
315 		if (!of_property_read_string(np, "label", &label))
316 			sensor_groups[type].attr_count++;
317 		if (of_find_property(np, "sensor-data-min", NULL))
318 			sensor_groups[type].attr_count++;
319 		if (of_find_property(np, "sensor-data-max", NULL))
320 			sensor_groups[type].attr_count++;
321 	}
322 
323 	of_node_put(opal);
324 
325 	for (type = 0; type < MAX_SENSOR_TYPE; type++) {
326 		sensor_groups[type].group.attrs = devm_kzalloc(&pdev->dev,
327 					sizeof(struct attribute *) *
328 					(sensor_groups[type].attr_count + 1),
329 					GFP_KERNEL);
330 		if (!sensor_groups[type].group.attrs)
331 			return -ENOMEM;
332 
333 		pgroups[type] = &sensor_groups[type].group;
334 		pdata->sensors_count += sensor_groups[type].attr_count;
335 		sensor_groups[type].attr_count = 0;
336 	}
337 
338 	return 0;
339 }
340 
341 static void create_hwmon_attr(struct sensor_data *sdata, const char *attr_name,
342 			      ssize_t (*show)(struct device *dev,
343 					      struct device_attribute *attr,
344 					      char *buf))
345 {
346 	snprintf(sdata->name, MAX_ATTR_LEN, "%s%d_%s",
347 		 sensor_groups[sdata->type].name, sdata->hwmon_index,
348 		 attr_name);
349 
350 	sysfs_attr_init(&sdata->dev_attr.attr);
351 	sdata->dev_attr.attr.name = sdata->name;
352 	sdata->dev_attr.attr.mode = S_IRUGO;
353 	sdata->dev_attr.show = show;
354 }
355 
356 static void populate_sensor(struct sensor_data *sdata, int od, int hd, int sid,
357 			    const char *attr_name, enum sensors type,
358 			    const struct attribute_group *pgroup,
359 			    ssize_t (*show)(struct device *dev,
360 					    struct device_attribute *attr,
361 					    char *buf))
362 {
363 	sdata->id = sid;
364 	sdata->type = type;
365 	sdata->opal_index = od;
366 	sdata->hwmon_index = hd;
367 	create_hwmon_attr(sdata, attr_name, show);
368 	pgroup->attrs[sensor_groups[type].attr_count++] = &sdata->dev_attr.attr;
369 }
370 
371 static char *get_max_attr(enum sensors type)
372 {
373 	switch (type) {
374 	case POWER_INPUT:
375 		return "input_highest";
376 	default:
377 		return "highest";
378 	}
379 }
380 
381 static char *get_min_attr(enum sensors type)
382 {
383 	switch (type) {
384 	case POWER_INPUT:
385 		return "input_lowest";
386 	default:
387 		return "lowest";
388 	}
389 }
390 
391 /*
392  * Iterate through the device tree for each child of 'sensors' node, create
393  * a sysfs attribute file, the file is named by translating the DT node name
394  * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
395  * etc..
396  */
397 static int create_device_attrs(struct platform_device *pdev)
398 {
399 	struct platform_data *pdata = platform_get_drvdata(pdev);
400 	const struct attribute_group **pgroups = pdata->attr_groups;
401 	struct device_node *opal, *np;
402 	struct sensor_data *sdata;
403 	u32 sensor_id;
404 	enum sensors type;
405 	u32 count = 0;
406 	int err = 0;
407 
408 	opal = of_find_node_by_path("/ibm,opal/sensors");
409 	sdata = devm_kzalloc(&pdev->dev, pdata->sensors_count * sizeof(*sdata),
410 			     GFP_KERNEL);
411 	if (!sdata) {
412 		err = -ENOMEM;
413 		goto exit_put_node;
414 	}
415 
416 	for_each_child_of_node(opal, np) {
417 		const char *attr_name;
418 		u32 opal_index;
419 		const char *label;
420 
421 		if (np->name == NULL)
422 			continue;
423 
424 		type = get_sensor_type(np);
425 		if (type == MAX_SENSOR_TYPE)
426 			continue;
427 
428 		/*
429 		 * Newer device trees use a "sensor-data" property
430 		 * name for input.
431 		 */
432 		if (of_property_read_u32(np, "sensor-id", &sensor_id) &&
433 		    of_property_read_u32(np, "sensor-data", &sensor_id)) {
434 			dev_info(&pdev->dev,
435 				 "'sensor-id' missing in the node '%s'\n",
436 				 np->name);
437 			continue;
438 		}
439 
440 		sdata[count].id = sensor_id;
441 		sdata[count].type = type;
442 
443 		/*
444 		 * If we can not parse the node name, it means we are
445 		 * running on a newer device tree. We can just forget
446 		 * about the OPAL index and use a defaut value for the
447 		 * hwmon attribute name
448 		 */
449 		attr_name = parse_opal_node_name(np->name, type, &opal_index);
450 		if (IS_ERR(attr_name)) {
451 			attr_name = "input";
452 			opal_index = INVALID_INDEX;
453 		}
454 
455 		sdata[count].opal_index = opal_index;
456 		sdata[count].hwmon_index =
457 			get_sensor_hwmon_index(&sdata[count], sdata, count);
458 
459 		create_hwmon_attr(&sdata[count], attr_name, show_sensor);
460 
461 		pgroups[type]->attrs[sensor_groups[type].attr_count++] =
462 				&sdata[count++].dev_attr.attr;
463 
464 		if (!of_property_read_string(np, "label", &label)) {
465 			/*
466 			 * For the label attribute, we can reuse the
467 			 * "properties" of the previous "input"
468 			 * attribute. They are related to the same
469 			 * sensor.
470 			 */
471 
472 			make_sensor_label(np, &sdata[count], label);
473 			populate_sensor(&sdata[count], opal_index,
474 					sdata[count - 1].hwmon_index,
475 					sensor_id, "label", type, pgroups[type],
476 					show_label);
477 			count++;
478 		}
479 
480 		if (!of_property_read_u32(np, "sensor-data-max", &sensor_id)) {
481 			attr_name = get_max_attr(type);
482 			populate_sensor(&sdata[count], opal_index,
483 					sdata[count - 1].hwmon_index,
484 					sensor_id, attr_name, type,
485 					pgroups[type], show_sensor);
486 			count++;
487 		}
488 
489 		if (!of_property_read_u32(np, "sensor-data-min", &sensor_id)) {
490 			attr_name = get_min_attr(type);
491 			populate_sensor(&sdata[count], opal_index,
492 					sdata[count - 1].hwmon_index,
493 					sensor_id, attr_name, type,
494 					pgroups[type], show_sensor);
495 			count++;
496 		}
497 	}
498 
499 exit_put_node:
500 	of_node_put(opal);
501 	return err;
502 }
503 
504 static int ibmpowernv_probe(struct platform_device *pdev)
505 {
506 	struct platform_data *pdata;
507 	struct device *hwmon_dev;
508 	int err;
509 
510 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
511 	if (!pdata)
512 		return -ENOMEM;
513 
514 	platform_set_drvdata(pdev, pdata);
515 	pdata->sensors_count = 0;
516 	err = populate_attr_groups(pdev);
517 	if (err)
518 		return err;
519 
520 	/* Create sysfs attribute data for each sensor found in the DT */
521 	err = create_device_attrs(pdev);
522 	if (err)
523 		return err;
524 
525 	/* Finally, register with hwmon */
526 	hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
527 							   pdata,
528 							   pdata->attr_groups);
529 
530 	return PTR_ERR_OR_ZERO(hwmon_dev);
531 }
532 
533 static const struct platform_device_id opal_sensor_driver_ids[] = {
534 	{
535 		.name = "opal-sensor",
536 	},
537 	{ }
538 };
539 MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids);
540 
541 static const struct of_device_id opal_sensor_match[] = {
542 	{ .compatible	= "ibm,opal-sensor" },
543 	{ },
544 };
545 MODULE_DEVICE_TABLE(of, opal_sensor_match);
546 
547 static struct platform_driver ibmpowernv_driver = {
548 	.probe		= ibmpowernv_probe,
549 	.id_table	= opal_sensor_driver_ids,
550 	.driver		= {
551 		.name	= DRVNAME,
552 		.of_match_table	= opal_sensor_match,
553 	},
554 };
555 
556 module_platform_driver(ibmpowernv_driver);
557 
558 MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
559 MODULE_DESCRIPTION("IBM POWERNV platform sensors");
560 MODULE_LICENSE("GPL");
561