xref: /openbmc/linux/drivers/hwmon/ibmpowernv.c (revision 94cdda6b)
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. Let's print out the range of
147 			 * cpu ids corresponding to the hardware
148 			 * threads of the core.
149 			 */
150 			n += snprintf(sdata->label + n,
151 				      sizeof(sdata->label) - n, " %d-%d",
152 				      cpuid, cpuid + threads_per_core - 1);
153 		else
154 			n += snprintf(sdata->label + n,
155 				      sizeof(sdata->label) - n, " phy%d", id);
156 	}
157 
158 	/*
159 	 * Membuffer pretty print
160 	 */
161 	if (!of_property_read_u32(np, "ibm,chip-id", &id))
162 		n += snprintf(sdata->label + n, sizeof(sdata->label) - n,
163 			      " %d", id & 0xffff);
164 }
165 
166 static int get_sensor_index_attr(const char *name, u32 *index, char *attr)
167 {
168 	char *hash_pos = strchr(name, '#');
169 	char buf[8] = { 0 };
170 	char *dash_pos;
171 	u32 copy_len;
172 	int err;
173 
174 	if (!hash_pos)
175 		return -EINVAL;
176 
177 	dash_pos = strchr(hash_pos, '-');
178 	if (!dash_pos)
179 		return -EINVAL;
180 
181 	copy_len = dash_pos - hash_pos - 1;
182 	if (copy_len >= sizeof(buf))
183 		return -EINVAL;
184 
185 	strncpy(buf, hash_pos + 1, copy_len);
186 
187 	err = kstrtou32(buf, 10, index);
188 	if (err)
189 		return err;
190 
191 	strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);
192 
193 	return 0;
194 }
195 
196 static const char *convert_opal_attr_name(enum sensors type,
197 					  const char *opal_attr)
198 {
199 	const char *attr_name = NULL;
200 
201 	if (!strcmp(opal_attr, DT_FAULT_ATTR_SUFFIX)) {
202 		attr_name = "fault";
203 	} else if (!strcmp(opal_attr, DT_DATA_ATTR_SUFFIX)) {
204 		attr_name = "input";
205 	} else if (!strcmp(opal_attr, DT_THRESHOLD_ATTR_SUFFIX)) {
206 		if (type == TEMP)
207 			attr_name = "max";
208 		else if (type == FAN)
209 			attr_name = "min";
210 	}
211 
212 	return attr_name;
213 }
214 
215 /*
216  * This function translates the DT node name into the 'hwmon' attribute name.
217  * IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
218  * which need to be mapped as fan2_input, temp1_max respectively before
219  * populating them inside hwmon device class.
220  */
221 static const char *parse_opal_node_name(const char *node_name,
222 					enum sensors type, u32 *index)
223 {
224 	char attr_suffix[MAX_ATTR_LEN];
225 	const char *attr_name;
226 	int err;
227 
228 	err = get_sensor_index_attr(node_name, index, attr_suffix);
229 	if (err)
230 		return ERR_PTR(err);
231 
232 	attr_name = convert_opal_attr_name(type, attr_suffix);
233 	if (!attr_name)
234 		return ERR_PTR(-ENOENT);
235 
236 	return attr_name;
237 }
238 
239 static int get_sensor_type(struct device_node *np)
240 {
241 	enum sensors type;
242 	const char *str;
243 
244 	for (type = 0; type < MAX_SENSOR_TYPE; type++) {
245 		if (of_device_is_compatible(np, sensor_groups[type].compatible))
246 			return type;
247 	}
248 
249 	/*
250 	 * Let's check if we have a newer device tree
251 	 */
252 	if (!of_device_is_compatible(np, "ibm,opal-sensor"))
253 		return MAX_SENSOR_TYPE;
254 
255 	if (of_property_read_string(np, "sensor-type", &str))
256 		return MAX_SENSOR_TYPE;
257 
258 	for (type = 0; type < MAX_SENSOR_TYPE; type++)
259 		if (!strcmp(str, sensor_groups[type].name))
260 			return type;
261 
262 	return MAX_SENSOR_TYPE;
263 }
264 
265 static u32 get_sensor_hwmon_index(struct sensor_data *sdata,
266 				  struct sensor_data *sdata_table, int count)
267 {
268 	int i;
269 
270 	/*
271 	 * We don't use the OPAL index on newer device trees
272 	 */
273 	if (sdata->opal_index != INVALID_INDEX) {
274 		for (i = 0; i < count; i++)
275 			if (sdata_table[i].opal_index == sdata->opal_index &&
276 			    sdata_table[i].type == sdata->type)
277 				return sdata_table[i].hwmon_index;
278 	}
279 	return ++sensor_groups[sdata->type].hwmon_index;
280 }
281 
282 static int populate_attr_groups(struct platform_device *pdev)
283 {
284 	struct platform_data *pdata = platform_get_drvdata(pdev);
285 	const struct attribute_group **pgroups = pdata->attr_groups;
286 	struct device_node *opal, *np;
287 	enum sensors type;
288 
289 	opal = of_find_node_by_path("/ibm,opal/sensors");
290 	for_each_child_of_node(opal, np) {
291 		const char *label;
292 
293 		if (np->name == NULL)
294 			continue;
295 
296 		type = get_sensor_type(np);
297 		if (type == MAX_SENSOR_TYPE)
298 			continue;
299 
300 		sensor_groups[type].attr_count++;
301 
302 		/*
303 		 * add a new attribute for labels
304 		 */
305 		if (!of_property_read_string(np, "label", &label))
306 			sensor_groups[type].attr_count++;
307 	}
308 
309 	of_node_put(opal);
310 
311 	for (type = 0; type < MAX_SENSOR_TYPE; type++) {
312 		sensor_groups[type].group.attrs = devm_kzalloc(&pdev->dev,
313 					sizeof(struct attribute *) *
314 					(sensor_groups[type].attr_count + 1),
315 					GFP_KERNEL);
316 		if (!sensor_groups[type].group.attrs)
317 			return -ENOMEM;
318 
319 		pgroups[type] = &sensor_groups[type].group;
320 		pdata->sensors_count += sensor_groups[type].attr_count;
321 		sensor_groups[type].attr_count = 0;
322 	}
323 
324 	return 0;
325 }
326 
327 static void create_hwmon_attr(struct sensor_data *sdata, const char *attr_name,
328 			      ssize_t (*show)(struct device *dev,
329 					      struct device_attribute *attr,
330 					      char *buf))
331 {
332 	snprintf(sdata->name, MAX_ATTR_LEN, "%s%d_%s",
333 		 sensor_groups[sdata->type].name, sdata->hwmon_index,
334 		 attr_name);
335 
336 	sysfs_attr_init(&sdata->dev_attr.attr);
337 	sdata->dev_attr.attr.name = sdata->name;
338 	sdata->dev_attr.attr.mode = S_IRUGO;
339 	sdata->dev_attr.show = show;
340 }
341 
342 /*
343  * Iterate through the device tree for each child of 'sensors' node, create
344  * a sysfs attribute file, the file is named by translating the DT node name
345  * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
346  * etc..
347  */
348 static int create_device_attrs(struct platform_device *pdev)
349 {
350 	struct platform_data *pdata = platform_get_drvdata(pdev);
351 	const struct attribute_group **pgroups = pdata->attr_groups;
352 	struct device_node *opal, *np;
353 	struct sensor_data *sdata;
354 	u32 sensor_id;
355 	enum sensors type;
356 	u32 count = 0;
357 	int err = 0;
358 
359 	opal = of_find_node_by_path("/ibm,opal/sensors");
360 	sdata = devm_kzalloc(&pdev->dev, pdata->sensors_count * sizeof(*sdata),
361 			     GFP_KERNEL);
362 	if (!sdata) {
363 		err = -ENOMEM;
364 		goto exit_put_node;
365 	}
366 
367 	for_each_child_of_node(opal, np) {
368 		const char *attr_name;
369 		u32 opal_index;
370 		const char *label;
371 
372 		if (np->name == NULL)
373 			continue;
374 
375 		type = get_sensor_type(np);
376 		if (type == MAX_SENSOR_TYPE)
377 			continue;
378 
379 		/*
380 		 * Newer device trees use a "sensor-data" property
381 		 * name for input.
382 		 */
383 		if (of_property_read_u32(np, "sensor-id", &sensor_id) &&
384 		    of_property_read_u32(np, "sensor-data", &sensor_id)) {
385 			dev_info(&pdev->dev,
386 				 "'sensor-id' missing in the node '%s'\n",
387 				 np->name);
388 			continue;
389 		}
390 
391 		sdata[count].id = sensor_id;
392 		sdata[count].type = type;
393 
394 		/*
395 		 * If we can not parse the node name, it means we are
396 		 * running on a newer device tree. We can just forget
397 		 * about the OPAL index and use a defaut value for the
398 		 * hwmon attribute name
399 		 */
400 		attr_name = parse_opal_node_name(np->name, type, &opal_index);
401 		if (IS_ERR(attr_name)) {
402 			attr_name = "input";
403 			opal_index = INVALID_INDEX;
404 		}
405 
406 		sdata[count].opal_index = opal_index;
407 		sdata[count].hwmon_index =
408 			get_sensor_hwmon_index(&sdata[count], sdata, count);
409 
410 		create_hwmon_attr(&sdata[count], attr_name, show_sensor);
411 
412 		pgroups[type]->attrs[sensor_groups[type].attr_count++] =
413 				&sdata[count++].dev_attr.attr;
414 
415 		if (!of_property_read_string(np, "label", &label)) {
416 			/*
417 			 * For the label attribute, we can reuse the
418 			 * "properties" of the previous "input"
419 			 * attribute. They are related to the same
420 			 * sensor.
421 			 */
422 			sdata[count].type = type;
423 			sdata[count].opal_index = sdata[count - 1].opal_index;
424 			sdata[count].hwmon_index = sdata[count - 1].hwmon_index;
425 
426 			make_sensor_label(np, &sdata[count], label);
427 
428 			create_hwmon_attr(&sdata[count], "label", show_label);
429 
430 			pgroups[type]->attrs[sensor_groups[type].attr_count++] =
431 				&sdata[count++].dev_attr.attr;
432 		}
433 	}
434 
435 exit_put_node:
436 	of_node_put(opal);
437 	return err;
438 }
439 
440 static int ibmpowernv_probe(struct platform_device *pdev)
441 {
442 	struct platform_data *pdata;
443 	struct device *hwmon_dev;
444 	int err;
445 
446 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
447 	if (!pdata)
448 		return -ENOMEM;
449 
450 	platform_set_drvdata(pdev, pdata);
451 	pdata->sensors_count = 0;
452 	err = populate_attr_groups(pdev);
453 	if (err)
454 		return err;
455 
456 	/* Create sysfs attribute data for each sensor found in the DT */
457 	err = create_device_attrs(pdev);
458 	if (err)
459 		return err;
460 
461 	/* Finally, register with hwmon */
462 	hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
463 							   pdata,
464 							   pdata->attr_groups);
465 
466 	return PTR_ERR_OR_ZERO(hwmon_dev);
467 }
468 
469 static const struct platform_device_id opal_sensor_driver_ids[] = {
470 	{
471 		.name = "opal-sensor",
472 	},
473 	{ }
474 };
475 MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids);
476 
477 static struct platform_driver ibmpowernv_driver = {
478 	.probe		= ibmpowernv_probe,
479 	.id_table	= opal_sensor_driver_ids,
480 	.driver		= {
481 		.name	= DRVNAME,
482 	},
483 };
484 
485 module_platform_driver(ibmpowernv_driver);
486 
487 MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
488 MODULE_DESCRIPTION("IBM POWERNV platform sensors");
489 MODULE_LICENSE("GPL");
490