xref: /openbmc/linux/drivers/hwmon/ibmpowernv.c (revision 4f6cce39)
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 	MAX_SENSOR_TYPE,
54 };
55 
56 #define INVALID_INDEX (-1U)
57 
58 static struct sensor_group {
59 	const char *name;
60 	const char *compatible;
61 	struct attribute_group group;
62 	u32 attr_count;
63 	u32 hwmon_index;
64 } sensor_groups[] = {
65 	{"fan", "ibm,opal-sensor-cooling-fan"},
66 	{"temp", "ibm,opal-sensor-amb-temp"},
67 	{"in", "ibm,opal-sensor-power-supply"},
68 	{"power", "ibm,opal-sensor-power"}
69 };
70 
71 struct sensor_data {
72 	u32 id; /* An opaque id of the firmware for each sensor */
73 	u32 hwmon_index;
74 	u32 opal_index;
75 	enum sensors type;
76 	char label[MAX_LABEL_LEN];
77 	char name[MAX_ATTR_LEN];
78 	struct device_attribute dev_attr;
79 };
80 
81 struct platform_data {
82 	const struct attribute_group *attr_groups[MAX_SENSOR_TYPE + 1];
83 	u32 sensors_count; /* Total count of sensors from each group */
84 };
85 
86 static ssize_t show_sensor(struct device *dev, struct device_attribute *devattr,
87 			   char *buf)
88 {
89 	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
90 						 dev_attr);
91 	ssize_t ret;
92 	u32 x;
93 
94 	ret = opal_get_sensor_data(sdata->id, &x);
95 	if (ret)
96 		return ret;
97 
98 	/* Convert temperature to milli-degrees */
99 	if (sdata->type == TEMP)
100 		x *= 1000;
101 	/* Convert power to micro-watts */
102 	else if (sdata->type == POWER_INPUT)
103 		x *= 1000000;
104 
105 	return sprintf(buf, "%u\n", x);
106 }
107 
108 static ssize_t show_label(struct device *dev, struct device_attribute *devattr,
109 			  char *buf)
110 {
111 	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
112 						 dev_attr);
113 
114 	return sprintf(buf, "%s\n", sdata->label);
115 }
116 
117 static int __init get_logical_cpu(int hwcpu)
118 {
119 	int cpu;
120 
121 	for_each_possible_cpu(cpu)
122 		if (get_hard_smp_processor_id(cpu) == hwcpu)
123 			return cpu;
124 
125 	return -ENOENT;
126 }
127 
128 static void __init make_sensor_label(struct device_node *np,
129 				     struct sensor_data *sdata,
130 				     const char *label)
131 {
132 	u32 id;
133 	size_t n;
134 
135 	n = snprintf(sdata->label, sizeof(sdata->label), "%s", label);
136 
137 	/*
138 	 * Core temp pretty print
139 	 */
140 	if (!of_property_read_u32(np, "ibm,pir", &id)) {
141 		int cpuid = get_logical_cpu(id);
142 
143 		if (cpuid >= 0)
144 			/*
145 			 * The digital thermal sensors are associated
146 			 * with a core.
147 			 */
148 			n += snprintf(sdata->label + n,
149 				      sizeof(sdata->label) - n, " %d",
150 				      cpuid);
151 		else
152 			n += snprintf(sdata->label + n,
153 				      sizeof(sdata->label) - n, " phy%d", id);
154 	}
155 
156 	/*
157 	 * Membuffer pretty print
158 	 */
159 	if (!of_property_read_u32(np, "ibm,chip-id", &id))
160 		n += snprintf(sdata->label + n, sizeof(sdata->label) - n,
161 			      " %d", id & 0xffff);
162 }
163 
164 static int get_sensor_index_attr(const char *name, u32 *index, char *attr)
165 {
166 	char *hash_pos = strchr(name, '#');
167 	char buf[8] = { 0 };
168 	char *dash_pos;
169 	u32 copy_len;
170 	int err;
171 
172 	if (!hash_pos)
173 		return -EINVAL;
174 
175 	dash_pos = strchr(hash_pos, '-');
176 	if (!dash_pos)
177 		return -EINVAL;
178 
179 	copy_len = dash_pos - hash_pos - 1;
180 	if (copy_len >= sizeof(buf))
181 		return -EINVAL;
182 
183 	strncpy(buf, hash_pos + 1, copy_len);
184 
185 	err = kstrtou32(buf, 10, index);
186 	if (err)
187 		return err;
188 
189 	strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);
190 
191 	return 0;
192 }
193 
194 static const char *convert_opal_attr_name(enum sensors type,
195 					  const char *opal_attr)
196 {
197 	const char *attr_name = NULL;
198 
199 	if (!strcmp(opal_attr, DT_FAULT_ATTR_SUFFIX)) {
200 		attr_name = "fault";
201 	} else if (!strcmp(opal_attr, DT_DATA_ATTR_SUFFIX)) {
202 		attr_name = "input";
203 	} else if (!strcmp(opal_attr, DT_THRESHOLD_ATTR_SUFFIX)) {
204 		if (type == TEMP)
205 			attr_name = "max";
206 		else if (type == FAN)
207 			attr_name = "min";
208 	}
209 
210 	return attr_name;
211 }
212 
213 /*
214  * This function translates the DT node name into the 'hwmon' attribute name.
215  * IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
216  * which need to be mapped as fan2_input, temp1_max respectively before
217  * populating them inside hwmon device class.
218  */
219 static const char *parse_opal_node_name(const char *node_name,
220 					enum sensors type, u32 *index)
221 {
222 	char attr_suffix[MAX_ATTR_LEN];
223 	const char *attr_name;
224 	int err;
225 
226 	err = get_sensor_index_attr(node_name, index, attr_suffix);
227 	if (err)
228 		return ERR_PTR(err);
229 
230 	attr_name = convert_opal_attr_name(type, attr_suffix);
231 	if (!attr_name)
232 		return ERR_PTR(-ENOENT);
233 
234 	return attr_name;
235 }
236 
237 static int get_sensor_type(struct device_node *np)
238 {
239 	enum sensors type;
240 	const char *str;
241 
242 	for (type = 0; type < MAX_SENSOR_TYPE; type++) {
243 		if (of_device_is_compatible(np, sensor_groups[type].compatible))
244 			return type;
245 	}
246 
247 	/*
248 	 * Let's check if we have a newer device tree
249 	 */
250 	if (!of_device_is_compatible(np, "ibm,opal-sensor"))
251 		return MAX_SENSOR_TYPE;
252 
253 	if (of_property_read_string(np, "sensor-type", &str))
254 		return MAX_SENSOR_TYPE;
255 
256 	for (type = 0; type < MAX_SENSOR_TYPE; type++)
257 		if (!strcmp(str, sensor_groups[type].name))
258 			return type;
259 
260 	return MAX_SENSOR_TYPE;
261 }
262 
263 static u32 get_sensor_hwmon_index(struct sensor_data *sdata,
264 				  struct sensor_data *sdata_table, int count)
265 {
266 	int i;
267 
268 	/*
269 	 * We don't use the OPAL index on newer device trees
270 	 */
271 	if (sdata->opal_index != INVALID_INDEX) {
272 		for (i = 0; i < count; i++)
273 			if (sdata_table[i].opal_index == sdata->opal_index &&
274 			    sdata_table[i].type == sdata->type)
275 				return sdata_table[i].hwmon_index;
276 	}
277 	return ++sensor_groups[sdata->type].hwmon_index;
278 }
279 
280 static int populate_attr_groups(struct platform_device *pdev)
281 {
282 	struct platform_data *pdata = platform_get_drvdata(pdev);
283 	const struct attribute_group **pgroups = pdata->attr_groups;
284 	struct device_node *opal, *np;
285 	enum sensors type;
286 
287 	opal = of_find_node_by_path("/ibm,opal/sensors");
288 	for_each_child_of_node(opal, np) {
289 		const char *label;
290 
291 		if (np->name == NULL)
292 			continue;
293 
294 		type = get_sensor_type(np);
295 		if (type == MAX_SENSOR_TYPE)
296 			continue;
297 
298 		sensor_groups[type].attr_count++;
299 
300 		/*
301 		 * add a new attribute for labels
302 		 */
303 		if (!of_property_read_string(np, "label", &label))
304 			sensor_groups[type].attr_count++;
305 	}
306 
307 	of_node_put(opal);
308 
309 	for (type = 0; type < MAX_SENSOR_TYPE; type++) {
310 		sensor_groups[type].group.attrs = devm_kzalloc(&pdev->dev,
311 					sizeof(struct attribute *) *
312 					(sensor_groups[type].attr_count + 1),
313 					GFP_KERNEL);
314 		if (!sensor_groups[type].group.attrs)
315 			return -ENOMEM;
316 
317 		pgroups[type] = &sensor_groups[type].group;
318 		pdata->sensors_count += sensor_groups[type].attr_count;
319 		sensor_groups[type].attr_count = 0;
320 	}
321 
322 	return 0;
323 }
324 
325 static void create_hwmon_attr(struct sensor_data *sdata, const char *attr_name,
326 			      ssize_t (*show)(struct device *dev,
327 					      struct device_attribute *attr,
328 					      char *buf))
329 {
330 	snprintf(sdata->name, MAX_ATTR_LEN, "%s%d_%s",
331 		 sensor_groups[sdata->type].name, sdata->hwmon_index,
332 		 attr_name);
333 
334 	sysfs_attr_init(&sdata->dev_attr.attr);
335 	sdata->dev_attr.attr.name = sdata->name;
336 	sdata->dev_attr.attr.mode = S_IRUGO;
337 	sdata->dev_attr.show = show;
338 }
339 
340 /*
341  * Iterate through the device tree for each child of 'sensors' node, create
342  * a sysfs attribute file, the file is named by translating the DT node name
343  * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
344  * etc..
345  */
346 static int create_device_attrs(struct platform_device *pdev)
347 {
348 	struct platform_data *pdata = platform_get_drvdata(pdev);
349 	const struct attribute_group **pgroups = pdata->attr_groups;
350 	struct device_node *opal, *np;
351 	struct sensor_data *sdata;
352 	u32 sensor_id;
353 	enum sensors type;
354 	u32 count = 0;
355 	int err = 0;
356 
357 	opal = of_find_node_by_path("/ibm,opal/sensors");
358 	sdata = devm_kzalloc(&pdev->dev, pdata->sensors_count * sizeof(*sdata),
359 			     GFP_KERNEL);
360 	if (!sdata) {
361 		err = -ENOMEM;
362 		goto exit_put_node;
363 	}
364 
365 	for_each_child_of_node(opal, np) {
366 		const char *attr_name;
367 		u32 opal_index;
368 		const char *label;
369 
370 		if (np->name == NULL)
371 			continue;
372 
373 		type = get_sensor_type(np);
374 		if (type == MAX_SENSOR_TYPE)
375 			continue;
376 
377 		/*
378 		 * Newer device trees use a "sensor-data" property
379 		 * name for input.
380 		 */
381 		if (of_property_read_u32(np, "sensor-id", &sensor_id) &&
382 		    of_property_read_u32(np, "sensor-data", &sensor_id)) {
383 			dev_info(&pdev->dev,
384 				 "'sensor-id' missing in the node '%s'\n",
385 				 np->name);
386 			continue;
387 		}
388 
389 		sdata[count].id = sensor_id;
390 		sdata[count].type = type;
391 
392 		/*
393 		 * If we can not parse the node name, it means we are
394 		 * running on a newer device tree. We can just forget
395 		 * about the OPAL index and use a defaut value for the
396 		 * hwmon attribute name
397 		 */
398 		attr_name = parse_opal_node_name(np->name, type, &opal_index);
399 		if (IS_ERR(attr_name)) {
400 			attr_name = "input";
401 			opal_index = INVALID_INDEX;
402 		}
403 
404 		sdata[count].opal_index = opal_index;
405 		sdata[count].hwmon_index =
406 			get_sensor_hwmon_index(&sdata[count], sdata, count);
407 
408 		create_hwmon_attr(&sdata[count], attr_name, show_sensor);
409 
410 		pgroups[type]->attrs[sensor_groups[type].attr_count++] =
411 				&sdata[count++].dev_attr.attr;
412 
413 		if (!of_property_read_string(np, "label", &label)) {
414 			/*
415 			 * For the label attribute, we can reuse the
416 			 * "properties" of the previous "input"
417 			 * attribute. They are related to the same
418 			 * sensor.
419 			 */
420 			sdata[count].type = type;
421 			sdata[count].opal_index = sdata[count - 1].opal_index;
422 			sdata[count].hwmon_index = sdata[count - 1].hwmon_index;
423 
424 			make_sensor_label(np, &sdata[count], label);
425 
426 			create_hwmon_attr(&sdata[count], "label", show_label);
427 
428 			pgroups[type]->attrs[sensor_groups[type].attr_count++] =
429 				&sdata[count++].dev_attr.attr;
430 		}
431 	}
432 
433 exit_put_node:
434 	of_node_put(opal);
435 	return err;
436 }
437 
438 static int ibmpowernv_probe(struct platform_device *pdev)
439 {
440 	struct platform_data *pdata;
441 	struct device *hwmon_dev;
442 	int err;
443 
444 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
445 	if (!pdata)
446 		return -ENOMEM;
447 
448 	platform_set_drvdata(pdev, pdata);
449 	pdata->sensors_count = 0;
450 	err = populate_attr_groups(pdev);
451 	if (err)
452 		return err;
453 
454 	/* Create sysfs attribute data for each sensor found in the DT */
455 	err = create_device_attrs(pdev);
456 	if (err)
457 		return err;
458 
459 	/* Finally, register with hwmon */
460 	hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
461 							   pdata,
462 							   pdata->attr_groups);
463 
464 	return PTR_ERR_OR_ZERO(hwmon_dev);
465 }
466 
467 static const struct platform_device_id opal_sensor_driver_ids[] = {
468 	{
469 		.name = "opal-sensor",
470 	},
471 	{ }
472 };
473 MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids);
474 
475 static const struct of_device_id opal_sensor_match[] = {
476 	{ .compatible	= "ibm,opal-sensor" },
477 	{ },
478 };
479 MODULE_DEVICE_TABLE(of, opal_sensor_match);
480 
481 static struct platform_driver ibmpowernv_driver = {
482 	.probe		= ibmpowernv_probe,
483 	.id_table	= opal_sensor_driver_ids,
484 	.driver		= {
485 		.name	= DRVNAME,
486 		.of_match_table	= opal_sensor_match,
487 	},
488 };
489 
490 module_platform_driver(ibmpowernv_driver);
491 
492 MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
493 MODULE_DESCRIPTION("IBM POWERNV platform sensors");
494 MODULE_LICENSE("GPL");
495