blob: 4b2b999b7611cb04390dfa1c6c3b5ac208d26069 [file] [log] [blame]
Eduardo Valentin4e5e4702013-07-03 15:35:39 -04001/*
2 * of-thermal.c - Generic Thermal Management device tree support.
3 *
4 * Copyright (C) 2013 Texas Instruments
5 * Copyright (C) 2013 Eduardo Valentin <eduardo.valentin@ti.com>
6 *
7 *
8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; version 2 of the License.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22 *
23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24 */
25#include <linux/thermal.h>
26#include <linux/slab.h>
27#include <linux/types.h>
28#include <linux/of_device.h>
29#include <linux/of_platform.h>
30#include <linux/err.h>
31#include <linux/export.h>
32#include <linux/string.h>
33
34#include "thermal_core.h"
35
36/*** Private data structures to represent thermal device tree data ***/
37
38/**
39 * struct __thermal_trip - representation of a point in temperature domain
40 * @np: pointer to struct device_node that this trip point was created from
41 * @temperature: temperature value in miliCelsius
42 * @hysteresis: relative hysteresis in miliCelsius
43 * @type: trip point type
44 */
45
46struct __thermal_trip {
47 struct device_node *np;
48 unsigned long int temperature;
49 unsigned long int hysteresis;
50 enum thermal_trip_type type;
51};
52
53/**
54 * struct __thermal_bind_param - a match between trip and cooling device
55 * @cooling_device: a pointer to identify the referred cooling device
56 * @trip_id: the trip point index
57 * @usage: the percentage (from 0 to 100) of cooling contribution
58 * @min: minimum cooling state used at this trip point
59 * @max: maximum cooling state used at this trip point
60 */
61
62struct __thermal_bind_params {
63 struct device_node *cooling_device;
64 unsigned int trip_id;
65 unsigned int usage;
66 unsigned long min;
67 unsigned long max;
68};
69
70/**
71 * struct __thermal_zone - internal representation of a thermal zone
72 * @mode: current thermal zone device mode (enabled/disabled)
73 * @passive_delay: polling interval while passive cooling is activated
74 * @polling_delay: zone polling interval
75 * @ntrips: number of trip points
76 * @trips: an array of trip points (0..ntrips - 1)
77 * @num_tbps: number of thermal bind params
78 * @tbps: an array of thermal bind params (0..num_tbps - 1)
79 * @sensor_data: sensor private data used while reading temperature and trend
80 * @get_temp: sensor callback to read temperature
81 * @get_trend: sensor callback to read temperature trend
82 */
83
84struct __thermal_zone {
85 enum thermal_device_mode mode;
86 int passive_delay;
87 int polling_delay;
88
89 /* trip data */
90 int ntrips;
91 struct __thermal_trip *trips;
92
93 /* cooling binding data */
94 int num_tbps;
95 struct __thermal_bind_params *tbps;
96
97 /* sensor interface */
98 void *sensor_data;
99 int (*get_temp)(void *, long *);
100 int (*get_trend)(void *, long *);
101};
102
103/*** DT thermal zone device callbacks ***/
104
105static int of_thermal_get_temp(struct thermal_zone_device *tz,
106 unsigned long *temp)
107{
108 struct __thermal_zone *data = tz->devdata;
109
110 if (!data->get_temp)
111 return -EINVAL;
112
113 return data->get_temp(data->sensor_data, temp);
114}
115
116static int of_thermal_get_trend(struct thermal_zone_device *tz, int trip,
117 enum thermal_trend *trend)
118{
119 struct __thermal_zone *data = tz->devdata;
120 long dev_trend;
121 int r;
122
123 if (!data->get_trend)
124 return -EINVAL;
125
126 r = data->get_trend(data->sensor_data, &dev_trend);
127 if (r)
128 return r;
129
130 /* TODO: These intervals might have some thresholds, but in core code */
131 if (dev_trend > 0)
132 *trend = THERMAL_TREND_RAISING;
133 else if (dev_trend < 0)
134 *trend = THERMAL_TREND_DROPPING;
135 else
136 *trend = THERMAL_TREND_STABLE;
137
138 return 0;
139}
140
141static int of_thermal_bind(struct thermal_zone_device *thermal,
142 struct thermal_cooling_device *cdev)
143{
144 struct __thermal_zone *data = thermal->devdata;
145 int i;
146
147 if (!data || IS_ERR(data))
148 return -ENODEV;
149
150 /* find where to bind */
151 for (i = 0; i < data->num_tbps; i++) {
152 struct __thermal_bind_params *tbp = data->tbps + i;
153
154 if (tbp->cooling_device == cdev->np) {
155 int ret;
156
157 ret = thermal_zone_bind_cooling_device(thermal,
158 tbp->trip_id, cdev,
Punit Agrawaldd354b82014-06-03 10:59:58 +0100159 tbp->max,
160 tbp->min);
Eduardo Valentin4e5e4702013-07-03 15:35:39 -0400161 if (ret)
162 return ret;
163 }
164 }
165
166 return 0;
167}
168
169static int of_thermal_unbind(struct thermal_zone_device *thermal,
170 struct thermal_cooling_device *cdev)
171{
172 struct __thermal_zone *data = thermal->devdata;
173 int i;
174
175 if (!data || IS_ERR(data))
176 return -ENODEV;
177
178 /* find where to unbind */
179 for (i = 0; i < data->num_tbps; i++) {
180 struct __thermal_bind_params *tbp = data->tbps + i;
181
182 if (tbp->cooling_device == cdev->np) {
183 int ret;
184
185 ret = thermal_zone_unbind_cooling_device(thermal,
186 tbp->trip_id, cdev);
187 if (ret)
188 return ret;
189 }
190 }
191
192 return 0;
193}
194
195static int of_thermal_get_mode(struct thermal_zone_device *tz,
196 enum thermal_device_mode *mode)
197{
198 struct __thermal_zone *data = tz->devdata;
199
200 *mode = data->mode;
201
202 return 0;
203}
204
205static int of_thermal_set_mode(struct thermal_zone_device *tz,
206 enum thermal_device_mode mode)
207{
208 struct __thermal_zone *data = tz->devdata;
209
210 mutex_lock(&tz->lock);
211
212 if (mode == THERMAL_DEVICE_ENABLED)
213 tz->polling_delay = data->polling_delay;
214 else
215 tz->polling_delay = 0;
216
217 mutex_unlock(&tz->lock);
218
219 data->mode = mode;
220 thermal_zone_device_update(tz);
221
222 return 0;
223}
224
225static int of_thermal_get_trip_type(struct thermal_zone_device *tz, int trip,
226 enum thermal_trip_type *type)
227{
228 struct __thermal_zone *data = tz->devdata;
229
230 if (trip >= data->ntrips || trip < 0)
231 return -EDOM;
232
233 *type = data->trips[trip].type;
234
235 return 0;
236}
237
238static int of_thermal_get_trip_temp(struct thermal_zone_device *tz, int trip,
239 unsigned long *temp)
240{
241 struct __thermal_zone *data = tz->devdata;
242
243 if (trip >= data->ntrips || trip < 0)
244 return -EDOM;
245
246 *temp = data->trips[trip].temperature;
247
248 return 0;
249}
250
251static int of_thermal_set_trip_temp(struct thermal_zone_device *tz, int trip,
252 unsigned long temp)
253{
254 struct __thermal_zone *data = tz->devdata;
255
256 if (trip >= data->ntrips || trip < 0)
257 return -EDOM;
258
259 /* thermal framework should take care of data->mask & (1 << trip) */
260 data->trips[trip].temperature = temp;
261
262 return 0;
263}
264
265static int of_thermal_get_trip_hyst(struct thermal_zone_device *tz, int trip,
266 unsigned long *hyst)
267{
268 struct __thermal_zone *data = tz->devdata;
269
270 if (trip >= data->ntrips || trip < 0)
271 return -EDOM;
272
273 *hyst = data->trips[trip].hysteresis;
274
275 return 0;
276}
277
278static int of_thermal_set_trip_hyst(struct thermal_zone_device *tz, int trip,
279 unsigned long hyst)
280{
281 struct __thermal_zone *data = tz->devdata;
282
283 if (trip >= data->ntrips || trip < 0)
284 return -EDOM;
285
286 /* thermal framework should take care of data->mask & (1 << trip) */
287 data->trips[trip].hysteresis = hyst;
288
289 return 0;
290}
291
292static int of_thermal_get_crit_temp(struct thermal_zone_device *tz,
293 unsigned long *temp)
294{
295 struct __thermal_zone *data = tz->devdata;
296 int i;
297
298 for (i = 0; i < data->ntrips; i++)
299 if (data->trips[i].type == THERMAL_TRIP_CRITICAL) {
300 *temp = data->trips[i].temperature;
301 return 0;
302 }
303
304 return -EINVAL;
305}
306
307static struct thermal_zone_device_ops of_thermal_ops = {
308 .get_mode = of_thermal_get_mode,
309 .set_mode = of_thermal_set_mode,
310
311 .get_trip_type = of_thermal_get_trip_type,
312 .get_trip_temp = of_thermal_get_trip_temp,
313 .set_trip_temp = of_thermal_set_trip_temp,
314 .get_trip_hyst = of_thermal_get_trip_hyst,
315 .set_trip_hyst = of_thermal_set_trip_hyst,
316 .get_crit_temp = of_thermal_get_crit_temp,
317
318 .bind = of_thermal_bind,
319 .unbind = of_thermal_unbind,
320};
321
322/*** sensor API ***/
323
324static struct thermal_zone_device *
325thermal_zone_of_add_sensor(struct device_node *zone,
326 struct device_node *sensor, void *data,
327 int (*get_temp)(void *, long *),
328 int (*get_trend)(void *, long *))
329{
330 struct thermal_zone_device *tzd;
331 struct __thermal_zone *tz;
332
333 tzd = thermal_zone_get_zone_by_name(zone->name);
334 if (IS_ERR(tzd))
335 return ERR_PTR(-EPROBE_DEFER);
336
337 tz = tzd->devdata;
338
339 mutex_lock(&tzd->lock);
340 tz->get_temp = get_temp;
341 tz->get_trend = get_trend;
342 tz->sensor_data = data;
343
344 tzd->ops->get_temp = of_thermal_get_temp;
345 tzd->ops->get_trend = of_thermal_get_trend;
346 mutex_unlock(&tzd->lock);
347
348 return tzd;
349}
350
351/**
352 * thermal_zone_of_sensor_register - registers a sensor to a DT thermal zone
353 * @dev: a valid struct device pointer of a sensor device. Must contain
354 * a valid .of_node, for the sensor node.
355 * @sensor_id: a sensor identifier, in case the sensor IP has more
356 * than one sensors
357 * @data: a private pointer (owned by the caller) that will be passed
358 * back, when a temperature reading is needed.
359 * @get_temp: a pointer to a function that reads the sensor temperature.
360 * @get_trend: a pointer to a function that reads the sensor temperature trend.
361 *
362 * This function will search the list of thermal zones described in device
363 * tree and look for the zone that refer to the sensor device pointed by
364 * @dev->of_node as temperature providers. For the zone pointing to the
365 * sensor node, the sensor will be added to the DT thermal zone device.
366 *
367 * The thermal zone temperature is provided by the @get_temp function
368 * pointer. When called, it will have the private pointer @data back.
369 *
370 * The thermal zone temperature trend is provided by the @get_trend function
371 * pointer. When called, it will have the private pointer @data back.
372 *
373 * TODO:
374 * 01 - This function must enqueue the new sensor instead of using
375 * it as the only source of temperature values.
376 *
377 * 02 - There must be a way to match the sensor with all thermal zones
378 * that refer to it.
379 *
380 * Return: On success returns a valid struct thermal_zone_device,
381 * otherwise, it returns a corresponding ERR_PTR(). Caller must
382 * check the return value with help of IS_ERR() helper.
383 */
384struct thermal_zone_device *
385thermal_zone_of_sensor_register(struct device *dev, int sensor_id,
386 void *data, int (*get_temp)(void *, long *),
387 int (*get_trend)(void *, long *))
388{
389 struct device_node *np, *child, *sensor_np;
390
391 np = of_find_node_by_name(NULL, "thermal-zones");
392 if (!np)
393 return ERR_PTR(-ENODEV);
394
395 if (!dev || !dev->of_node)
396 return ERR_PTR(-EINVAL);
397
398 sensor_np = dev->of_node;
399
400 for_each_child_of_node(np, child) {
401 struct of_phandle_args sensor_specs;
402 int ret, id;
403
404 /* For now, thermal framework supports only 1 sensor per zone */
405 ret = of_parse_phandle_with_args(child, "thermal-sensors",
406 "#thermal-sensor-cells",
407 0, &sensor_specs);
408 if (ret)
409 continue;
410
411 if (sensor_specs.args_count >= 1) {
412 id = sensor_specs.args[0];
413 WARN(sensor_specs.args_count > 1,
414 "%s: too many cells in sensor specifier %d\n",
415 sensor_specs.np->name, sensor_specs.args_count);
416 } else {
417 id = 0;
418 }
419
420 if (sensor_specs.np == sensor_np && id == sensor_id) {
421 of_node_put(np);
422 return thermal_zone_of_add_sensor(child, sensor_np,
423 data,
424 get_temp,
425 get_trend);
426 }
427 }
428 of_node_put(np);
429
430 return ERR_PTR(-ENODEV);
431}
432EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_register);
433
434/**
435 * thermal_zone_of_sensor_unregister - unregisters a sensor from a DT thermal zone
436 * @dev: a valid struct device pointer of a sensor device. Must contain
437 * a valid .of_node, for the sensor node.
438 * @tzd: a pointer to struct thermal_zone_device where the sensor is registered.
439 *
440 * This function removes the sensor callbacks and private data from the
441 * thermal zone device registered with thermal_zone_of_sensor_register()
442 * API. It will also silent the zone by remove the .get_temp() and .get_trend()
443 * thermal zone device callbacks.
444 *
445 * TODO: When the support to several sensors per zone is added, this
446 * function must search the sensor list based on @dev parameter.
447 *
448 */
449void thermal_zone_of_sensor_unregister(struct device *dev,
450 struct thermal_zone_device *tzd)
451{
452 struct __thermal_zone *tz;
453
454 if (!dev || !tzd || !tzd->devdata)
455 return;
456
457 tz = tzd->devdata;
458
459 /* no __thermal_zone, nothing to be done */
460 if (!tz)
461 return;
462
463 mutex_lock(&tzd->lock);
464 tzd->ops->get_temp = NULL;
465 tzd->ops->get_trend = NULL;
466
467 tz->get_temp = NULL;
468 tz->get_trend = NULL;
469 tz->sensor_data = NULL;
470 mutex_unlock(&tzd->lock);
471}
472EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_unregister);
473
474/*** functions parsing device tree nodes ***/
475
476/**
477 * thermal_of_populate_bind_params - parse and fill cooling map data
478 * @np: DT node containing a cooling-map node
479 * @__tbp: data structure to be filled with cooling map info
480 * @trips: array of thermal zone trip points
481 * @ntrips: number of trip points inside trips.
482 *
483 * This function parses a cooling-map type of node represented by
484 * @np parameter and fills the read data into @__tbp data structure.
485 * It needs the already parsed array of trip points of the thermal zone
486 * in consideration.
487 *
488 * Return: 0 on success, proper error code otherwise
489 */
490static int thermal_of_populate_bind_params(struct device_node *np,
491 struct __thermal_bind_params *__tbp,
492 struct __thermal_trip *trips,
493 int ntrips)
494{
495 struct of_phandle_args cooling_spec;
496 struct device_node *trip;
497 int ret, i;
498 u32 prop;
499
500 /* Default weight. Usage is optional */
501 __tbp->usage = 0;
502 ret = of_property_read_u32(np, "contribution", &prop);
503 if (ret == 0)
504 __tbp->usage = prop;
505
506 trip = of_parse_phandle(np, "trip", 0);
507 if (!trip) {
508 pr_err("missing trip property\n");
509 return -ENODEV;
510 }
511
512 /* match using device_node */
513 for (i = 0; i < ntrips; i++)
514 if (trip == trips[i].np) {
515 __tbp->trip_id = i;
516 break;
517 }
518
519 if (i == ntrips) {
520 ret = -ENODEV;
521 goto end;
522 }
523
524 ret = of_parse_phandle_with_args(np, "cooling-device", "#cooling-cells",
525 0, &cooling_spec);
526 if (ret < 0) {
527 pr_err("missing cooling_device property\n");
528 goto end;
529 }
530 __tbp->cooling_device = cooling_spec.np;
531 if (cooling_spec.args_count >= 2) { /* at least min and max */
532 __tbp->min = cooling_spec.args[0];
533 __tbp->max = cooling_spec.args[1];
534 } else {
535 pr_err("wrong reference to cooling device, missing limits\n");
536 }
537
538end:
539 of_node_put(trip);
540
541 return ret;
542}
543
544/**
545 * It maps 'enum thermal_trip_type' found in include/linux/thermal.h
546 * into the device tree binding of 'trip', property type.
547 */
548static const char * const trip_types[] = {
549 [THERMAL_TRIP_ACTIVE] = "active",
550 [THERMAL_TRIP_PASSIVE] = "passive",
551 [THERMAL_TRIP_HOT] = "hot",
552 [THERMAL_TRIP_CRITICAL] = "critical",
553};
554
555/**
556 * thermal_of_get_trip_type - Get phy mode for given device_node
557 * @np: Pointer to the given device_node
558 * @type: Pointer to resulting trip type
559 *
560 * The function gets trip type string from property 'type',
561 * and store its index in trip_types table in @type,
562 *
563 * Return: 0 on success, or errno in error case.
564 */
565static int thermal_of_get_trip_type(struct device_node *np,
566 enum thermal_trip_type *type)
567{
568 const char *t;
569 int err, i;
570
571 err = of_property_read_string(np, "type", &t);
572 if (err < 0)
573 return err;
574
575 for (i = 0; i < ARRAY_SIZE(trip_types); i++)
576 if (!strcasecmp(t, trip_types[i])) {
577 *type = i;
578 return 0;
579 }
580
581 return -ENODEV;
582}
583
584/**
585 * thermal_of_populate_trip - parse and fill one trip point data
586 * @np: DT node containing a trip point node
587 * @trip: trip point data structure to be filled up
588 *
589 * This function parses a trip point type of node represented by
590 * @np parameter and fills the read data into @trip data structure.
591 *
592 * Return: 0 on success, proper error code otherwise
593 */
594static int thermal_of_populate_trip(struct device_node *np,
595 struct __thermal_trip *trip)
596{
597 int prop;
598 int ret;
599
600 ret = of_property_read_u32(np, "temperature", &prop);
601 if (ret < 0) {
602 pr_err("missing temperature property\n");
603 return ret;
604 }
605 trip->temperature = prop;
606
607 ret = of_property_read_u32(np, "hysteresis", &prop);
608 if (ret < 0) {
609 pr_err("missing hysteresis property\n");
610 return ret;
611 }
612 trip->hysteresis = prop;
613
614 ret = thermal_of_get_trip_type(np, &trip->type);
615 if (ret < 0) {
616 pr_err("wrong trip type property\n");
617 return ret;
618 }
619
620 /* Required for cooling map matching */
621 trip->np = np;
622
623 return 0;
624}
625
626/**
627 * thermal_of_build_thermal_zone - parse and fill one thermal zone data
628 * @np: DT node containing a thermal zone node
629 *
630 * This function parses a thermal zone type of node represented by
631 * @np parameter and fills the read data into a __thermal_zone data structure
632 * and return this pointer.
633 *
634 * TODO: Missing properties to parse: thermal-sensor-names and coefficients
635 *
636 * Return: On success returns a valid struct __thermal_zone,
637 * otherwise, it returns a corresponding ERR_PTR(). Caller must
638 * check the return value with help of IS_ERR() helper.
639 */
640static struct __thermal_zone *
641thermal_of_build_thermal_zone(struct device_node *np)
642{
643 struct device_node *child = NULL, *gchild;
644 struct __thermal_zone *tz;
645 int ret, i;
646 u32 prop;
647
648 if (!np) {
649 pr_err("no thermal zone np\n");
650 return ERR_PTR(-EINVAL);
651 }
652
653 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
654 if (!tz)
655 return ERR_PTR(-ENOMEM);
656
657 ret = of_property_read_u32(np, "polling-delay-passive", &prop);
658 if (ret < 0) {
659 pr_err("missing polling-delay-passive property\n");
660 goto free_tz;
661 }
662 tz->passive_delay = prop;
663
664 ret = of_property_read_u32(np, "polling-delay", &prop);
665 if (ret < 0) {
666 pr_err("missing polling-delay property\n");
667 goto free_tz;
668 }
669 tz->polling_delay = prop;
670
671 /* trips */
672 child = of_get_child_by_name(np, "trips");
673
674 /* No trips provided */
675 if (!child)
676 goto finish;
677
678 tz->ntrips = of_get_child_count(child);
679 if (tz->ntrips == 0) /* must have at least one child */
680 goto finish;
681
682 tz->trips = kzalloc(tz->ntrips * sizeof(*tz->trips), GFP_KERNEL);
683 if (!tz->trips) {
684 ret = -ENOMEM;
685 goto free_tz;
686 }
687
688 i = 0;
689 for_each_child_of_node(child, gchild) {
690 ret = thermal_of_populate_trip(gchild, &tz->trips[i++]);
691 if (ret)
692 goto free_trips;
693 }
694
695 of_node_put(child);
696
697 /* cooling-maps */
698 child = of_get_child_by_name(np, "cooling-maps");
699
700 /* cooling-maps not provided */
701 if (!child)
702 goto finish;
703
704 tz->num_tbps = of_get_child_count(child);
705 if (tz->num_tbps == 0)
706 goto finish;
707
708 tz->tbps = kzalloc(tz->num_tbps * sizeof(*tz->tbps), GFP_KERNEL);
709 if (!tz->tbps) {
710 ret = -ENOMEM;
711 goto free_trips;
712 }
713
714 i = 0;
Stephen Boydca9521b2014-06-18 16:32:08 -0700715 for_each_child_of_node(child, gchild) {
Eduardo Valentin4e5e4702013-07-03 15:35:39 -0400716 ret = thermal_of_populate_bind_params(gchild, &tz->tbps[i++],
717 tz->trips, tz->ntrips);
718 if (ret)
719 goto free_tbps;
Stephen Boydca9521b2014-06-18 16:32:08 -0700720 }
Eduardo Valentin4e5e4702013-07-03 15:35:39 -0400721
722finish:
723 of_node_put(child);
724 tz->mode = THERMAL_DEVICE_DISABLED;
725
726 return tz;
727
728free_tbps:
729 kfree(tz->tbps);
730free_trips:
731 kfree(tz->trips);
732free_tz:
733 kfree(tz);
734 of_node_put(child);
735
736 return ERR_PTR(ret);
737}
738
739static inline void of_thermal_free_zone(struct __thermal_zone *tz)
740{
741 kfree(tz->tbps);
742 kfree(tz->trips);
743 kfree(tz);
744}
745
746/**
747 * of_parse_thermal_zones - parse device tree thermal data
748 *
749 * Initialization function that can be called by machine initialization
750 * code to parse thermal data and populate the thermal framework
751 * with hardware thermal zones info. This function only parses thermal zones.
752 * Cooling devices and sensor devices nodes are supposed to be parsed
753 * by their respective drivers.
754 *
755 * Return: 0 on success, proper error code otherwise
756 *
757 */
758int __init of_parse_thermal_zones(void)
759{
760 struct device_node *np, *child;
761 struct __thermal_zone *tz;
762 struct thermal_zone_device_ops *ops;
763
764 np = of_find_node_by_name(NULL, "thermal-zones");
765 if (!np) {
766 pr_debug("unable to find thermal zones\n");
767 return 0; /* Run successfully on systems without thermal DT */
768 }
769
770 for_each_child_of_node(np, child) {
771 struct thermal_zone_device *zone;
772 struct thermal_zone_params *tzp;
773
774 tz = thermal_of_build_thermal_zone(child);
775 if (IS_ERR(tz)) {
776 pr_err("failed to build thermal zone %s: %ld\n",
777 child->name,
778 PTR_ERR(tz));
779 continue;
780 }
781
782 ops = kmemdup(&of_thermal_ops, sizeof(*ops), GFP_KERNEL);
783 if (!ops)
784 goto exit_free;
785
786 tzp = kzalloc(sizeof(*tzp), GFP_KERNEL);
787 if (!tzp) {
788 kfree(ops);
789 goto exit_free;
790 }
791
792 /* No hwmon because there might be hwmon drivers registering */
793 tzp->no_hwmon = true;
794
795 zone = thermal_zone_device_register(child->name, tz->ntrips,
796 0, tz,
797 ops, tzp,
798 tz->passive_delay,
799 tz->polling_delay);
800 if (IS_ERR(zone)) {
801 pr_err("Failed to build %s zone %ld\n", child->name,
802 PTR_ERR(zone));
803 kfree(tzp);
804 kfree(ops);
805 of_thermal_free_zone(tz);
806 /* attempting to build remaining zones still */
807 }
808 }
809
810 return 0;
811
812exit_free:
813 of_thermal_free_zone(tz);
814
815 /* no memory available, so free what we have built */
816 of_thermal_destroy_zones();
817
818 return -ENOMEM;
819}
820
821/**
822 * of_thermal_destroy_zones - remove all zones parsed and allocated resources
823 *
824 * Finds all zones parsed and added to the thermal framework and remove them
825 * from the system, together with their resources.
826 *
827 */
828void of_thermal_destroy_zones(void)
829{
830 struct device_node *np, *child;
831
832 np = of_find_node_by_name(NULL, "thermal-zones");
833 if (!np) {
834 pr_err("unable to find thermal zones\n");
835 return;
836 }
837
838 for_each_child_of_node(np, child) {
839 struct thermal_zone_device *zone;
840
841 zone = thermal_zone_get_zone_by_name(child->name);
842 if (IS_ERR(zone))
843 continue;
844
845 thermal_zone_device_unregister(zone);
846 kfree(zone->tzp);
847 kfree(zone->ops);
848 of_thermal_free_zone(zone->devdata);
849 }
850}