xref: /linux/drivers/power/supply/power_supply_core.c (revision 07b43820437bd96f31f5d7f9baf4453fcb7dedbf)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Universal power supply monitor class
4  *
5  *  Copyright © 2007  Anton Vorontsov <cbou@mail.ru>
6  *  Copyright © 2004  Szabolcs Gyurko
7  *  Copyright © 2003  Ian Molton <spyro@f2s.com>
8  *
9  *  Modified: 2004, Oct     Szabolcs Gyurko
10  */
11 
12 #include <linux/cleanup.h>
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/init.h>
16 #include <linux/slab.h>
17 #include <linux/delay.h>
18 #include <linux/device.h>
19 #include <linux/notifier.h>
20 #include <linux/err.h>
21 #include <linux/power_supply.h>
22 #include <linux/property.h>
23 #include <linux/thermal.h>
24 #include <linux/fixp-arith.h>
25 #include "power_supply.h"
26 #include "samsung-sdi-battery.h"
27 
28 static const struct class power_supply_class = {
29 	.name = "power_supply",
30 	.dev_uevent = power_supply_uevent,
31 };
32 
33 static BLOCKING_NOTIFIER_HEAD(power_supply_notifier);
34 
35 static const struct device_type power_supply_dev_type = {
36 	.name = "power_supply",
37 	.groups = power_supply_attr_groups,
38 };
39 
40 #define POWER_SUPPLY_DEFERRED_REGISTER_TIME	msecs_to_jiffies(10)
41 
__power_supply_is_supplied_by(struct power_supply * supplier,struct power_supply * supply)42 static bool __power_supply_is_supplied_by(struct power_supply *supplier,
43 					 struct power_supply *supply)
44 {
45 	int i;
46 
47 	if (!supply->supplied_from && !supplier->supplied_to)
48 		return false;
49 
50 	/* Support both supplied_to and supplied_from modes */
51 	if (supply->supplied_from) {
52 		if (!supplier->desc->name)
53 			return false;
54 		for (i = 0; i < supply->num_supplies; i++)
55 			if (!strcmp(supplier->desc->name, supply->supplied_from[i]))
56 				return true;
57 	} else {
58 		if (!supply->desc->name)
59 			return false;
60 		for (i = 0; i < supplier->num_supplicants; i++)
61 			if (!strcmp(supplier->supplied_to[i], supply->desc->name))
62 				return true;
63 	}
64 
65 	return false;
66 }
67 
__power_supply_changed_work(struct power_supply * pst,void * data)68 static int __power_supply_changed_work(struct power_supply *pst, void *data)
69 {
70 	struct power_supply *psy = data;
71 
72 	if (__power_supply_is_supplied_by(psy, pst))
73 		power_supply_external_power_changed(pst);
74 
75 	return 0;
76 }
77 
power_supply_changed_work(struct work_struct * work)78 static void power_supply_changed_work(struct work_struct *work)
79 {
80 	int ret;
81 	unsigned long flags;
82 	struct power_supply *psy = container_of(work, struct power_supply,
83 						changed_work);
84 
85 	dev_dbg(&psy->dev, "%s\n", __func__);
86 
87 	spin_lock_irqsave(&psy->changed_lock, flags);
88 
89 	if (unlikely(psy->update_groups)) {
90 		psy->update_groups = false;
91 		spin_unlock_irqrestore(&psy->changed_lock, flags);
92 		ret = sysfs_update_groups(&psy->dev.kobj, power_supply_dev_type.groups);
93 		if (ret)
94 			dev_warn(&psy->dev, "failed to update sysfs groups: %pe\n", ERR_PTR(ret));
95 		spin_lock_irqsave(&psy->changed_lock, flags);
96 	}
97 
98 	/*
99 	 * Check 'changed' here to avoid issues due to race between
100 	 * power_supply_changed() and this routine. In worst case
101 	 * power_supply_changed() can be called again just before we take above
102 	 * lock. During the first call of this routine we will mark 'changed' as
103 	 * false and it will stay false for the next call as well.
104 	 */
105 	if (likely(psy->changed)) {
106 		psy->changed = false;
107 		spin_unlock_irqrestore(&psy->changed_lock, flags);
108 		power_supply_for_each_psy(psy, __power_supply_changed_work);
109 		power_supply_update_leds(psy);
110 		blocking_notifier_call_chain(&power_supply_notifier,
111 				PSY_EVENT_PROP_CHANGED, psy);
112 		kobject_uevent(&psy->dev.kobj, KOBJ_CHANGE);
113 		spin_lock_irqsave(&psy->changed_lock, flags);
114 	}
115 
116 	/*
117 	 * Hold the wakeup_source until all events are processed.
118 	 * power_supply_changed() might have called again and have set 'changed'
119 	 * to true.
120 	 */
121 	if (likely(!psy->changed))
122 		pm_relax(&psy->dev);
123 	spin_unlock_irqrestore(&psy->changed_lock, flags);
124 }
125 
126 struct psy_for_each_psy_cb_data {
127 	int (*fn)(struct power_supply *psy, void *data);
128 	void *data;
129 };
130 
psy_for_each_psy_cb(struct device * dev,void * data)131 static int psy_for_each_psy_cb(struct device *dev, void *data)
132 {
133 	struct psy_for_each_psy_cb_data *cb_data = data;
134 	struct power_supply *psy = dev_to_psy(dev);
135 
136 	return cb_data->fn(psy, cb_data->data);
137 }
138 
power_supply_for_each_psy(void * data,int (* fn)(struct power_supply * psy,void * data))139 int power_supply_for_each_psy(void *data, int (*fn)(struct power_supply *psy, void *data))
140 {
141 	struct psy_for_each_psy_cb_data cb_data = {
142 		.fn = fn,
143 		.data = data,
144 	};
145 
146 	return class_for_each_device(&power_supply_class, NULL, &cb_data, psy_for_each_psy_cb);
147 }
148 EXPORT_SYMBOL_GPL(power_supply_for_each_psy);
149 
power_supply_changed(struct power_supply * psy)150 void power_supply_changed(struct power_supply *psy)
151 {
152 	unsigned long flags;
153 
154 	dev_dbg(&psy->dev, "%s\n", __func__);
155 
156 	spin_lock_irqsave(&psy->changed_lock, flags);
157 	psy->changed = true;
158 	pm_stay_awake(&psy->dev);
159 	spin_unlock_irqrestore(&psy->changed_lock, flags);
160 	schedule_work(&psy->changed_work);
161 }
162 EXPORT_SYMBOL_GPL(power_supply_changed);
163 
164 /*
165  * Notify that power supply was registered after parent finished the probing.
166  *
167  * Often power supply is registered from driver's probe function. However
168  * calling power_supply_changed() directly from power_supply_register()
169  * would lead to execution of get_property() function provided by the driver
170  * too early - before the probe ends.
171  *
172  * Avoid that by waiting on parent's mutex.
173  */
power_supply_deferred_register_work(struct work_struct * work)174 static void power_supply_deferred_register_work(struct work_struct *work)
175 {
176 	struct power_supply *psy = container_of(work, struct power_supply,
177 						deferred_register_work.work);
178 
179 	if (psy->dev.parent) {
180 		while (!device_trylock(psy->dev.parent)) {
181 			if (psy->removing)
182 				return;
183 			msleep(10);
184 		}
185 	}
186 
187 	power_supply_changed(psy);
188 
189 	if (psy->dev.parent)
190 		device_unlock(psy->dev.parent);
191 }
192 
193 #ifdef CONFIG_OF
__power_supply_populate_supplied_from(struct power_supply * epsy,void * data)194 static int __power_supply_populate_supplied_from(struct power_supply *epsy,
195 						 void *data)
196 {
197 	struct power_supply *psy = data;
198 	struct fwnode_handle *np;
199 	int i = 0;
200 
201 	do {
202 		np = fwnode_find_reference(psy->dev.fwnode, "power-supplies", i++);
203 		if (IS_ERR(np))
204 			break;
205 
206 		if (np == epsy->dev.fwnode) {
207 			dev_dbg(&psy->dev, "%s: Found supply : %s\n",
208 				psy->desc->name, epsy->desc->name);
209 			psy->supplied_from[i-1] = (char *)epsy->desc->name;
210 			psy->num_supplies++;
211 			fwnode_handle_put(np);
212 			break;
213 		}
214 		fwnode_handle_put(np);
215 	} while (true);
216 
217 	return 0;
218 }
219 
power_supply_populate_supplied_from(struct power_supply * psy)220 static int power_supply_populate_supplied_from(struct power_supply *psy)
221 {
222 	int error;
223 
224 	error = power_supply_for_each_psy(psy, __power_supply_populate_supplied_from);
225 
226 	dev_dbg(&psy->dev, "%s %d\n", __func__, error);
227 
228 	return error;
229 }
230 
__power_supply_find_supply_from_node(struct power_supply * epsy,void * data)231 static int  __power_supply_find_supply_from_node(struct power_supply *epsy,
232 						 void *data)
233 {
234 	struct fwnode_handle *fwnode = data;
235 
236 	/* returning non-zero breaks out of power_supply_for_each_psy loop */
237 	if (epsy->dev.fwnode == fwnode)
238 		return 1;
239 
240 	return 0;
241 }
242 
power_supply_find_supply_from_fwnode(struct fwnode_handle * supply_node)243 static int power_supply_find_supply_from_fwnode(struct fwnode_handle *supply_node)
244 {
245 	int error;
246 
247 	/*
248 	 * power_supply_for_each_psy() either returns its own errors or values
249 	 * returned by __power_supply_find_supply_from_node().
250 	 *
251 	 * __power_supply_find_supply_from_fwnode() will return 0 (no match)
252 	 * or 1 (match).
253 	 *
254 	 * We return 0 if power_supply_for_each_psy() returned 1, -EPROBE_DEFER if
255 	 * it returned 0, or error as returned by it.
256 	 */
257 	error = power_supply_for_each_psy(supply_node, __power_supply_find_supply_from_node);
258 
259 	return error ? (error == 1 ? 0 : error) : -EPROBE_DEFER;
260 }
261 
power_supply_check_supplies(struct power_supply * psy)262 static int power_supply_check_supplies(struct power_supply *psy)
263 {
264 	struct fwnode_handle *np;
265 	int cnt = 0;
266 
267 	/* If there is already a list honor it */
268 	if (psy->supplied_from && psy->num_supplies > 0)
269 		return 0;
270 
271 	/* No device node found, nothing to do */
272 	if (!psy->dev.fwnode)
273 		return 0;
274 
275 	do {
276 		int ret;
277 
278 		np = fwnode_find_reference(psy->dev.fwnode, "power-supplies", cnt++);
279 		if (IS_ERR(np))
280 			break;
281 
282 		ret = power_supply_find_supply_from_fwnode(np);
283 		fwnode_handle_put(np);
284 
285 		if (ret) {
286 			dev_dbg(&psy->dev, "Failed to find supply!\n");
287 			return ret;
288 		}
289 	} while (!IS_ERR(np));
290 
291 	/* Missing valid "power-supplies" entries */
292 	if (cnt == 1)
293 		return 0;
294 
295 	/* All supplies found, allocate char ** array for filling */
296 	psy->supplied_from = devm_kzalloc(&psy->dev, sizeof(*psy->supplied_from),
297 					  GFP_KERNEL);
298 	if (!psy->supplied_from)
299 		return -ENOMEM;
300 
301 	*psy->supplied_from = devm_kcalloc(&psy->dev,
302 					   cnt - 1, sizeof(**psy->supplied_from),
303 					   GFP_KERNEL);
304 	if (!*psy->supplied_from)
305 		return -ENOMEM;
306 
307 	return power_supply_populate_supplied_from(psy);
308 }
309 #else
power_supply_check_supplies(struct power_supply * psy)310 static int power_supply_check_supplies(struct power_supply *psy)
311 {
312 	int nval, ret;
313 
314 	if (!psy->dev.parent)
315 		return 0;
316 
317 	nval = device_property_string_array_count(psy->dev.parent, "supplied-from");
318 	if (nval <= 0)
319 		return 0;
320 
321 	psy->supplied_from = devm_kmalloc_array(&psy->dev, nval,
322 						sizeof(char *), GFP_KERNEL);
323 	if (!psy->supplied_from)
324 		return -ENOMEM;
325 
326 	ret = device_property_read_string_array(psy->dev.parent,
327 		"supplied-from", (const char **)psy->supplied_from, nval);
328 	if (ret < 0)
329 		return ret;
330 
331 	psy->num_supplies = nval;
332 
333 	return 0;
334 }
335 #endif
336 
337 struct psy_am_i_supplied_data {
338 	struct power_supply *psy;
339 	unsigned int count;
340 };
341 
__power_supply_am_i_supplied(struct power_supply * epsy,void * _data)342 static int __power_supply_am_i_supplied(struct power_supply *epsy, void *_data)
343 {
344 	union power_supply_propval ret = {0,};
345 	struct psy_am_i_supplied_data *data = _data;
346 
347 	if (__power_supply_is_supplied_by(epsy, data->psy)) {
348 		data->count++;
349 		if (!epsy->desc->get_property(epsy, POWER_SUPPLY_PROP_ONLINE,
350 					&ret))
351 			return ret.intval;
352 	}
353 
354 	return 0;
355 }
356 
power_supply_am_i_supplied(struct power_supply * psy)357 int power_supply_am_i_supplied(struct power_supply *psy)
358 {
359 	struct psy_am_i_supplied_data data = { psy, 0 };
360 	int error;
361 
362 	error = power_supply_for_each_psy(&data, __power_supply_am_i_supplied);
363 
364 	dev_dbg(&psy->dev, "%s count %u err %d\n", __func__, data.count, error);
365 
366 	if (data.count == 0)
367 		return -ENODEV;
368 
369 	return error;
370 }
371 EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
372 
__power_supply_is_system_supplied(struct power_supply * psy,void * data)373 static int __power_supply_is_system_supplied(struct power_supply *psy, void *data)
374 {
375 	union power_supply_propval ret = {0,};
376 	unsigned int *count = data;
377 
378 	if (!psy->desc->get_property(psy, POWER_SUPPLY_PROP_SCOPE, &ret))
379 		if (ret.intval == POWER_SUPPLY_SCOPE_DEVICE)
380 			return 0;
381 
382 	(*count)++;
383 	if (psy->desc->type != POWER_SUPPLY_TYPE_BATTERY)
384 		if (!psy->desc->get_property(psy, POWER_SUPPLY_PROP_ONLINE,
385 					&ret))
386 			return ret.intval;
387 
388 	return 0;
389 }
390 
power_supply_is_system_supplied(void)391 int power_supply_is_system_supplied(void)
392 {
393 	int error;
394 	unsigned int count = 0;
395 
396 	error = power_supply_for_each_psy(&count, __power_supply_is_system_supplied);
397 
398 	/*
399 	 * If no system scope power class device was found at all, most probably we
400 	 * are running on a desktop system, so assume we are on mains power.
401 	 */
402 	if (count == 0)
403 		return 1;
404 
405 	return error;
406 }
407 EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);
408 
409 struct psy_get_supplier_prop_data {
410 	struct power_supply *psy;
411 	enum power_supply_property psp;
412 	union power_supply_propval *val;
413 };
414 
__power_supply_get_supplier_property(struct power_supply * epsy,void * _data)415 static int __power_supply_get_supplier_property(struct power_supply *epsy, void *_data)
416 {
417 	struct psy_get_supplier_prop_data *data = _data;
418 
419 	if (__power_supply_is_supplied_by(epsy, data->psy))
420 		if (!power_supply_get_property(epsy, data->psp, data->val))
421 			return 1; /* Success */
422 
423 	return 0; /* Continue iterating */
424 }
425 
power_supply_get_property_from_supplier(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)426 int power_supply_get_property_from_supplier(struct power_supply *psy,
427 					    enum power_supply_property psp,
428 					    union power_supply_propval *val)
429 {
430 	struct psy_get_supplier_prop_data data = {
431 		.psy = psy,
432 		.psp = psp,
433 		.val = val,
434 	};
435 	int ret;
436 
437 	/*
438 	 * This function is not intended for use with a supply with multiple
439 	 * suppliers, we simply pick the first supply to report the psp.
440 	 */
441 	ret = power_supply_for_each_psy(&data, __power_supply_get_supplier_property);
442 	if (ret < 0)
443 		return ret;
444 	if (ret == 0)
445 		return -ENODEV;
446 
447 	return 0;
448 }
449 EXPORT_SYMBOL_GPL(power_supply_get_property_from_supplier);
450 
power_supply_match_device_by_name(struct device * dev,const void * data)451 static int power_supply_match_device_by_name(struct device *dev, const void *data)
452 {
453 	const char *name = data;
454 	struct power_supply *psy = dev_to_psy(dev);
455 
456 	return strcmp(psy->desc->name, name) == 0;
457 }
458 
459 /**
460  * power_supply_get_by_name() - Search for a power supply and returns its ref
461  * @name: Power supply name to fetch
462  *
463  * If power supply was found, it increases reference count for the
464  * internal power supply's device. The user should power_supply_put()
465  * after usage.
466  *
467  * Return: On success returns a reference to a power supply with
468  * matching name equals to @name, a NULL otherwise.
469  */
power_supply_get_by_name(const char * name)470 struct power_supply *power_supply_get_by_name(const char *name)
471 {
472 	struct power_supply *psy = NULL;
473 	struct device *dev = class_find_device(&power_supply_class, NULL, name,
474 					       power_supply_match_device_by_name);
475 
476 	if (dev) {
477 		psy = dev_to_psy(dev);
478 		atomic_inc(&psy->use_cnt);
479 	}
480 
481 	return psy;
482 }
483 EXPORT_SYMBOL_GPL(power_supply_get_by_name);
484 
485 /**
486  * power_supply_put() - Drop reference obtained with power_supply_get_by_name
487  * @psy: Reference to put
488  *
489  * The reference to power supply should be put before unregistering
490  * the power supply.
491  */
power_supply_put(struct power_supply * psy)492 void power_supply_put(struct power_supply *psy)
493 {
494 	atomic_dec(&psy->use_cnt);
495 	put_device(&psy->dev);
496 }
497 EXPORT_SYMBOL_GPL(power_supply_put);
498 
power_supply_match_device_fwnode(struct device * dev,const void * data)499 static int power_supply_match_device_fwnode(struct device *dev, const void *data)
500 {
501 	return dev->parent && dev_fwnode(dev->parent) == data;
502 }
503 
504 /**
505  * power_supply_get_by_reference() - Search for a power supply and returns its ref
506  * @fwnode: Pointer to fwnode holding phandle property
507  * @property: Name of property holding a power supply name
508  *
509  * If power supply was found, it increases reference count for the
510  * internal power supply's device. The user should power_supply_put()
511  * after usage.
512  *
513  * Return: On success returns a reference to a power supply with
514  * matching name equals to value under @property, NULL or ERR_PTR otherwise.
515  */
power_supply_get_by_reference(struct fwnode_handle * fwnode,const char * property)516 struct power_supply *power_supply_get_by_reference(struct fwnode_handle *fwnode,
517 						   const char *property)
518 {
519 	struct fwnode_handle *power_supply_fwnode;
520 	struct power_supply *psy = NULL;
521 	struct device *dev;
522 
523 	power_supply_fwnode = fwnode_find_reference(fwnode, property, 0);
524 	if (IS_ERR(power_supply_fwnode))
525 		return ERR_CAST(power_supply_fwnode);
526 
527 	dev = class_find_device(&power_supply_class, NULL, power_supply_fwnode,
528 				power_supply_match_device_fwnode);
529 
530 	fwnode_handle_put(power_supply_fwnode);
531 
532 	if (dev) {
533 		psy = dev_to_psy(dev);
534 		atomic_inc(&psy->use_cnt);
535 	}
536 
537 	return psy;
538 }
539 EXPORT_SYMBOL_GPL(power_supply_get_by_reference);
540 
devm_power_supply_put(struct device * dev,void * res)541 static void devm_power_supply_put(struct device *dev, void *res)
542 {
543 	struct power_supply **psy = res;
544 
545 	power_supply_put(*psy);
546 }
547 
548 /**
549  * devm_power_supply_get_by_reference() - Resource managed version of
550  *  power_supply_get_by_reference()
551  * @dev: Pointer to device holding phandle property
552  * @property: Name of property holding a power supply phandle
553  *
554  * Return: On success returns a reference to a power supply with
555  * matching name equals to value under @property, NULL or ERR_PTR otherwise.
556  */
devm_power_supply_get_by_reference(struct device * dev,const char * property)557 struct power_supply *devm_power_supply_get_by_reference(struct device *dev,
558 							const char *property)
559 {
560 	struct power_supply **ptr, *psy;
561 
562 	if (!dev_fwnode(dev))
563 		return ERR_PTR(-ENODEV);
564 
565 	ptr = devres_alloc(devm_power_supply_put, sizeof(*ptr), GFP_KERNEL);
566 	if (!ptr)
567 		return ERR_PTR(-ENOMEM);
568 
569 	psy = power_supply_get_by_reference(dev_fwnode(dev), property);
570 	if (IS_ERR_OR_NULL(psy)) {
571 		devres_free(ptr);
572 	} else {
573 		*ptr = psy;
574 		devres_add(dev, ptr);
575 	}
576 	return psy;
577 }
578 EXPORT_SYMBOL_GPL(devm_power_supply_get_by_reference);
579 
power_supply_get_battery_info(struct power_supply * psy,struct power_supply_battery_info ** info_out)580 int power_supply_get_battery_info(struct power_supply *psy,
581 				  struct power_supply_battery_info **info_out)
582 {
583 	struct power_supply_resistance_temp_table *resist_table;
584 	struct power_supply_battery_info *info;
585 	struct fwnode_handle *srcnode, *fwnode;
586 	const char *value;
587 	int err, len, index, proplen;
588 	u32 *propdata __free(kfree) = NULL;
589 	u32 min_max[2];
590 
591 	srcnode = dev_fwnode(&psy->dev);
592 	if (!srcnode && psy->dev.parent)
593 		srcnode = dev_fwnode(psy->dev.parent);
594 
595 	fwnode = fwnode_find_reference(srcnode, "monitored-battery", 0);
596 	if (IS_ERR(fwnode))
597 		return PTR_ERR(fwnode);
598 
599 	err = fwnode_property_read_string(fwnode, "compatible", &value);
600 	if (err)
601 		goto out_put_node;
602 
603 
604 	/* Try static batteries first */
605 	err = samsung_sdi_battery_get_info(&psy->dev, value, &info);
606 	if (!err)
607 		goto out_ret_pointer;
608 	else if (err == -ENODEV)
609 		/*
610 		 * Device does not have a static battery.
611 		 * Proceed to look for a simple battery.
612 		 */
613 		err = 0;
614 
615 	if (strcmp("simple-battery", value)) {
616 		err = -ENODEV;
617 		goto out_put_node;
618 	}
619 
620 	info = devm_kzalloc(&psy->dev, sizeof(*info), GFP_KERNEL);
621 	if (!info) {
622 		err = -ENOMEM;
623 		goto out_put_node;
624 	}
625 
626 	info->technology                     = POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
627 	info->energy_full_design_uwh         = -EINVAL;
628 	info->charge_full_design_uah         = -EINVAL;
629 	info->voltage_min_design_uv          = -EINVAL;
630 	info->voltage_max_design_uv          = -EINVAL;
631 	info->precharge_current_ua           = -EINVAL;
632 	info->charge_term_current_ua         = -EINVAL;
633 	info->constant_charge_current_max_ua = -EINVAL;
634 	info->constant_charge_voltage_max_uv = -EINVAL;
635 	info->tricklecharge_current_ua       = -EINVAL;
636 	info->precharge_voltage_max_uv       = -EINVAL;
637 	info->charge_restart_voltage_uv      = -EINVAL;
638 	info->overvoltage_limit_uv           = -EINVAL;
639 	info->maintenance_charge             = NULL;
640 	info->alert_low_temp_charge_current_ua = -EINVAL;
641 	info->alert_low_temp_charge_voltage_uv = -EINVAL;
642 	info->alert_high_temp_charge_current_ua = -EINVAL;
643 	info->alert_high_temp_charge_voltage_uv = -EINVAL;
644 	info->temp_ambient_alert_min         = INT_MIN;
645 	info->temp_ambient_alert_max         = INT_MAX;
646 	info->temp_alert_min                 = INT_MIN;
647 	info->temp_alert_max                 = INT_MAX;
648 	info->temp_min                       = INT_MIN;
649 	info->temp_max                       = INT_MAX;
650 	info->factory_internal_resistance_uohm  = -EINVAL;
651 	info->resist_table                   = NULL;
652 	info->bti_resistance_ohm             = -EINVAL;
653 	info->bti_resistance_tolerance       = -EINVAL;
654 
655 	for (index = 0; index < POWER_SUPPLY_OCV_TEMP_MAX; index++) {
656 		info->ocv_table[index]       = NULL;
657 		info->ocv_temp[index]        = -EINVAL;
658 		info->ocv_table_size[index]  = -EINVAL;
659 	}
660 
661 	/* The property and field names below must correspond to elements
662 	 * in enum power_supply_property. For reasoning, see
663 	 * Documentation/power/power_supply_class.rst.
664 	 */
665 
666 	if (!fwnode_property_read_string(fwnode, "device-chemistry", &value)) {
667 		if (!strcmp("nickel-cadmium", value))
668 			info->technology = POWER_SUPPLY_TECHNOLOGY_NiCd;
669 		else if (!strcmp("nickel-metal-hydride", value))
670 			info->technology = POWER_SUPPLY_TECHNOLOGY_NiMH;
671 		else if (!strcmp("lithium-ion", value))
672 			/* Imprecise lithium-ion type */
673 			info->technology = POWER_SUPPLY_TECHNOLOGY_LION;
674 		else if (!strcmp("lithium-ion-polymer", value))
675 			info->technology = POWER_SUPPLY_TECHNOLOGY_LIPO;
676 		else if (!strcmp("lithium-ion-iron-phosphate", value))
677 			info->technology = POWER_SUPPLY_TECHNOLOGY_LiFe;
678 		else if (!strcmp("lithium-ion-manganese-oxide", value))
679 			info->technology = POWER_SUPPLY_TECHNOLOGY_LiMn;
680 		else
681 			dev_warn(&psy->dev, "%s unknown battery type\n", value);
682 	}
683 
684 	fwnode_property_read_u32(fwnode, "energy-full-design-microwatt-hours",
685 			     &info->energy_full_design_uwh);
686 	fwnode_property_read_u32(fwnode, "charge-full-design-microamp-hours",
687 			     &info->charge_full_design_uah);
688 	fwnode_property_read_u32(fwnode, "voltage-min-design-microvolt",
689 			     &info->voltage_min_design_uv);
690 	fwnode_property_read_u32(fwnode, "voltage-max-design-microvolt",
691 			     &info->voltage_max_design_uv);
692 	fwnode_property_read_u32(fwnode, "trickle-charge-current-microamp",
693 			     &info->tricklecharge_current_ua);
694 	fwnode_property_read_u32(fwnode, "precharge-current-microamp",
695 			     &info->precharge_current_ua);
696 	fwnode_property_read_u32(fwnode, "precharge-upper-limit-microvolt",
697 			     &info->precharge_voltage_max_uv);
698 	fwnode_property_read_u32(fwnode, "charge-term-current-microamp",
699 			     &info->charge_term_current_ua);
700 	fwnode_property_read_u32(fwnode, "re-charge-voltage-microvolt",
701 			     &info->charge_restart_voltage_uv);
702 	fwnode_property_read_u32(fwnode, "over-voltage-threshold-microvolt",
703 			     &info->overvoltage_limit_uv);
704 	fwnode_property_read_u32(fwnode, "constant-charge-current-max-microamp",
705 			     &info->constant_charge_current_max_ua);
706 	fwnode_property_read_u32(fwnode, "constant-charge-voltage-max-microvolt",
707 			     &info->constant_charge_voltage_max_uv);
708 	fwnode_property_read_u32(fwnode, "factory-internal-resistance-micro-ohms",
709 			     &info->factory_internal_resistance_uohm);
710 
711 	if (!fwnode_property_read_u32_array(fwnode, "ambient-celsius",
712 					    min_max, ARRAY_SIZE(min_max))) {
713 		info->temp_ambient_alert_min = min_max[0];
714 		info->temp_ambient_alert_max = min_max[1];
715 	}
716 	if (!fwnode_property_read_u32_array(fwnode, "alert-celsius",
717 					    min_max, ARRAY_SIZE(min_max))) {
718 		info->temp_alert_min = min_max[0];
719 		info->temp_alert_max = min_max[1];
720 	}
721 	if (!fwnode_property_read_u32_array(fwnode, "operating-range-celsius",
722 					    min_max, ARRAY_SIZE(min_max))) {
723 		info->temp_min = min_max[0];
724 		info->temp_max = min_max[1];
725 	}
726 
727 	len = fwnode_property_count_u32(fwnode, "ocv-capacity-celsius");
728 	if (len < 0 && len != -EINVAL) {
729 		err = len;
730 		goto out_put_node;
731 	} else if (len > POWER_SUPPLY_OCV_TEMP_MAX) {
732 		dev_err(&psy->dev, "Too many temperature values\n");
733 		err = -EINVAL;
734 		goto out_put_node;
735 	} else if (len > 0) {
736 		fwnode_property_read_u32_array(fwnode, "ocv-capacity-celsius",
737 					   info->ocv_temp, len);
738 	}
739 
740 	for (index = 0; index < len; index++) {
741 		struct power_supply_battery_ocv_table *table;
742 		int i, tab_len;
743 
744 		char *propname __free(kfree) = kasprintf(GFP_KERNEL, "ocv-capacity-table-%d",
745 							 index);
746 		if (!propname) {
747 			power_supply_put_battery_info(psy, info);
748 			err = -ENOMEM;
749 			goto out_put_node;
750 		}
751 		proplen = fwnode_property_count_u32(fwnode, propname);
752 		if (proplen < 0 || proplen % 2 != 0) {
753 			dev_err(&psy->dev, "failed to get %s\n", propname);
754 			power_supply_put_battery_info(psy, info);
755 			err = -EINVAL;
756 			goto out_put_node;
757 		}
758 
759 		u32 *propdata __free(kfree) = kcalloc(proplen, sizeof(*propdata), GFP_KERNEL);
760 		if (!propdata) {
761 			power_supply_put_battery_info(psy, info);
762 			err = -EINVAL;
763 			goto out_put_node;
764 		}
765 		err = fwnode_property_read_u32_array(fwnode, propname, propdata, proplen);
766 		if (err < 0) {
767 			dev_err(&psy->dev, "failed to get %s\n", propname);
768 			power_supply_put_battery_info(psy, info);
769 			goto out_put_node;
770 		}
771 
772 		tab_len = proplen / 2;
773 		info->ocv_table_size[index] = tab_len;
774 
775 		info->ocv_table[index] = table =
776 			devm_kcalloc(&psy->dev, tab_len, sizeof(*table), GFP_KERNEL);
777 		if (!info->ocv_table[index]) {
778 			power_supply_put_battery_info(psy, info);
779 			err = -ENOMEM;
780 			goto out_put_node;
781 		}
782 
783 		for (i = 0; i < tab_len; i++) {
784 			table[i].ocv = propdata[i*2];
785 			table[i].capacity = propdata[i*2+1];
786 		}
787 	}
788 
789 	proplen = fwnode_property_count_u32(fwnode, "resistance-temp-table");
790 	if (proplen == 0 || proplen == -EINVAL) {
791 		err = 0;
792 		goto out_ret_pointer;
793 	} else if (proplen < 0 || proplen % 2 != 0) {
794 		power_supply_put_battery_info(psy, info);
795 		err = (proplen < 0) ? proplen : -EINVAL;
796 		goto out_put_node;
797 	}
798 
799 	propdata = kcalloc(proplen, sizeof(*propdata), GFP_KERNEL);
800 	if (!propdata) {
801 		power_supply_put_battery_info(psy, info);
802 		err = -ENOMEM;
803 		goto out_put_node;
804 	}
805 
806 	err = fwnode_property_read_u32_array(fwnode, "resistance-temp-table",
807 					     propdata, proplen);
808 	if (err < 0) {
809 		power_supply_put_battery_info(psy, info);
810 		goto out_put_node;
811 	}
812 
813 	info->resist_table_size = proplen / 2;
814 	info->resist_table = resist_table = devm_kcalloc(&psy->dev,
815 							 info->resist_table_size,
816 							 sizeof(*resist_table),
817 							 GFP_KERNEL);
818 	if (!info->resist_table) {
819 		power_supply_put_battery_info(psy, info);
820 		err = -ENOMEM;
821 		goto out_put_node;
822 	}
823 
824 	for (index = 0; index < info->resist_table_size; index++) {
825 		resist_table[index].temp = propdata[index*2];
826 		resist_table[index].resistance = propdata[index*2+1];
827 	}
828 
829 out_ret_pointer:
830 	/* Finally return the whole thing */
831 	*info_out = info;
832 
833 out_put_node:
834 	fwnode_handle_put(fwnode);
835 	return err;
836 }
837 EXPORT_SYMBOL_GPL(power_supply_get_battery_info);
838 
power_supply_put_battery_info(struct power_supply * psy,struct power_supply_battery_info * info)839 void power_supply_put_battery_info(struct power_supply *psy,
840 				   struct power_supply_battery_info *info)
841 {
842 	int i;
843 
844 	for (i = 0; i < POWER_SUPPLY_OCV_TEMP_MAX; i++) {
845 		if (info->ocv_table[i])
846 			devm_kfree(&psy->dev, info->ocv_table[i]);
847 	}
848 
849 	if (info->resist_table)
850 		devm_kfree(&psy->dev, info->resist_table);
851 
852 	devm_kfree(&psy->dev, info);
853 }
854 EXPORT_SYMBOL_GPL(power_supply_put_battery_info);
855 
856 const enum power_supply_property power_supply_battery_info_properties[] = {
857 	POWER_SUPPLY_PROP_TECHNOLOGY,
858 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
859 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
860 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
861 	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
862 	POWER_SUPPLY_PROP_PRECHARGE_CURRENT,
863 	POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT,
864 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
865 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
866 	POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MIN,
867 	POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MAX,
868 	POWER_SUPPLY_PROP_TEMP_ALERT_MIN,
869 	POWER_SUPPLY_PROP_TEMP_ALERT_MAX,
870 	POWER_SUPPLY_PROP_TEMP_MIN,
871 	POWER_SUPPLY_PROP_TEMP_MAX,
872 };
873 EXPORT_SYMBOL_GPL(power_supply_battery_info_properties);
874 
875 const size_t power_supply_battery_info_properties_size = ARRAY_SIZE(power_supply_battery_info_properties);
876 EXPORT_SYMBOL_GPL(power_supply_battery_info_properties_size);
877 
power_supply_battery_info_has_prop(struct power_supply_battery_info * info,enum power_supply_property psp)878 bool power_supply_battery_info_has_prop(struct power_supply_battery_info *info,
879 					enum power_supply_property psp)
880 {
881 	if (!info)
882 		return false;
883 
884 	switch (psp) {
885 	case POWER_SUPPLY_PROP_TECHNOLOGY:
886 		return info->technology != POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
887 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
888 		return info->energy_full_design_uwh >= 0;
889 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
890 		return info->charge_full_design_uah >= 0;
891 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
892 		return info->voltage_min_design_uv >= 0;
893 	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
894 		return info->voltage_max_design_uv >= 0;
895 	case POWER_SUPPLY_PROP_PRECHARGE_CURRENT:
896 		return info->precharge_current_ua >= 0;
897 	case POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT:
898 		return info->charge_term_current_ua >= 0;
899 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
900 		return info->constant_charge_current_max_ua >= 0;
901 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
902 		return info->constant_charge_voltage_max_uv >= 0;
903 	case POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MIN:
904 		return info->temp_ambient_alert_min > INT_MIN;
905 	case POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MAX:
906 		return info->temp_ambient_alert_max < INT_MAX;
907 	case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
908 		return info->temp_alert_min > INT_MIN;
909 	case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
910 		return info->temp_alert_max < INT_MAX;
911 	case POWER_SUPPLY_PROP_TEMP_MIN:
912 		return info->temp_min > INT_MIN;
913 	case POWER_SUPPLY_PROP_TEMP_MAX:
914 		return info->temp_max < INT_MAX;
915 	default:
916 		return false;
917 	}
918 }
919 EXPORT_SYMBOL_GPL(power_supply_battery_info_has_prop);
920 
power_supply_battery_info_get_prop(struct power_supply_battery_info * info,enum power_supply_property psp,union power_supply_propval * val)921 int power_supply_battery_info_get_prop(struct power_supply_battery_info *info,
922 				       enum power_supply_property psp,
923 				       union power_supply_propval *val)
924 {
925 	if (!info)
926 		return -EINVAL;
927 
928 	if (!power_supply_battery_info_has_prop(info, psp))
929 		return -EINVAL;
930 
931 	switch (psp) {
932 	case POWER_SUPPLY_PROP_TECHNOLOGY:
933 		val->intval = info->technology;
934 		return 0;
935 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
936 		val->intval = info->energy_full_design_uwh;
937 		return 0;
938 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
939 		val->intval = info->charge_full_design_uah;
940 		return 0;
941 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
942 		val->intval = info->voltage_min_design_uv;
943 		return 0;
944 	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
945 		val->intval = info->voltage_max_design_uv;
946 		return 0;
947 	case POWER_SUPPLY_PROP_PRECHARGE_CURRENT:
948 		val->intval = info->precharge_current_ua;
949 		return 0;
950 	case POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT:
951 		val->intval = info->charge_term_current_ua;
952 		return 0;
953 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
954 		val->intval = info->constant_charge_current_max_ua;
955 		return 0;
956 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
957 		val->intval = info->constant_charge_voltage_max_uv;
958 		return 0;
959 	case POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MIN:
960 		val->intval = info->temp_ambient_alert_min;
961 		return 0;
962 	case POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MAX:
963 		val->intval = info->temp_ambient_alert_max;
964 		return 0;
965 	case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
966 		val->intval = info->temp_alert_min;
967 		return 0;
968 	case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
969 		val->intval = info->temp_alert_max;
970 		return 0;
971 	case POWER_SUPPLY_PROP_TEMP_MIN:
972 		val->intval = info->temp_min;
973 		return 0;
974 	case POWER_SUPPLY_PROP_TEMP_MAX:
975 		val->intval = info->temp_max;
976 		return 0;
977 	default:
978 		return -EINVAL;
979 	}
980 }
981 EXPORT_SYMBOL_GPL(power_supply_battery_info_get_prop);
982 
983 /**
984  * power_supply_temp2resist_simple() - find the battery internal resistance
985  * percent from temperature
986  * @table: Pointer to battery resistance temperature table
987  * @table_len: The table length
988  * @temp: Current temperature
989  *
990  * This helper function is used to look up battery internal resistance percent
991  * according to current temperature value from the resistance temperature table,
992  * and the table must be ordered descending. Then the actual battery internal
993  * resistance = the ideal battery internal resistance * percent / 100.
994  *
995  * Return: the battery internal resistance percent
996  */
power_supply_temp2resist_simple(const struct power_supply_resistance_temp_table * table,int table_len,int temp)997 int power_supply_temp2resist_simple(const struct power_supply_resistance_temp_table *table,
998 				    int table_len, int temp)
999 {
1000 	int i, high, low;
1001 
1002 	for (i = 0; i < table_len; i++)
1003 		if (temp > table[i].temp)
1004 			break;
1005 
1006 	/* The library function will deal with high == low */
1007 	if (i == 0)
1008 		high = low = i;
1009 	else if (i == table_len)
1010 		high = low = i - 1;
1011 	else
1012 		high = (low = i) - 1;
1013 
1014 	return fixp_linear_interpolate(table[low].temp,
1015 				       table[low].resistance,
1016 				       table[high].temp,
1017 				       table[high].resistance,
1018 				       temp);
1019 }
1020 EXPORT_SYMBOL_GPL(power_supply_temp2resist_simple);
1021 
1022 /**
1023  * power_supply_vbat2ri() - find the battery internal resistance
1024  * from the battery voltage
1025  * @info: The battery information container
1026  * @vbat_uv: The battery voltage in microvolt
1027  * @charging: If we are charging (true) or not (false)
1028  *
1029  * This helper function is used to look up battery internal resistance
1030  * according to current battery voltage. Depending on whether the battery
1031  * is currently charging or not, different resistance will be returned.
1032  *
1033  * Returns the internal resistance in microohm or negative error code.
1034  */
power_supply_vbat2ri(struct power_supply_battery_info * info,int vbat_uv,bool charging)1035 int power_supply_vbat2ri(struct power_supply_battery_info *info,
1036 			 int vbat_uv, bool charging)
1037 {
1038 	const struct power_supply_vbat_ri_table *vbat2ri;
1039 	int table_len;
1040 	int i, high, low;
1041 
1042 	/*
1043 	 * If we are charging, and the battery supplies a separate table
1044 	 * for this state, we use that in order to compensate for the
1045 	 * charging voltage. Otherwise we use the main table.
1046 	 */
1047 	if (charging && info->vbat2ri_charging) {
1048 		vbat2ri = info->vbat2ri_charging;
1049 		table_len = info->vbat2ri_charging_size;
1050 	} else {
1051 		vbat2ri = info->vbat2ri_discharging;
1052 		table_len = info->vbat2ri_discharging_size;
1053 	}
1054 
1055 	/*
1056 	 * If no tables are specified, or if we are above the highest voltage in
1057 	 * the voltage table, just return the factory specified internal resistance.
1058 	 */
1059 	if (!vbat2ri || (table_len <= 0) || (vbat_uv > vbat2ri[0].vbat_uv)) {
1060 		if (charging && (info->factory_internal_resistance_charging_uohm > 0))
1061 			return info->factory_internal_resistance_charging_uohm;
1062 		else
1063 			return info->factory_internal_resistance_uohm;
1064 	}
1065 
1066 	/* Break loop at table_len - 1 because that is the highest index */
1067 	for (i = 0; i < table_len - 1; i++)
1068 		if (vbat_uv > vbat2ri[i].vbat_uv)
1069 			break;
1070 
1071 	/* The library function will deal with high == low */
1072 	if ((i == 0) || (i == (table_len - 1)))
1073 		high = i;
1074 	else
1075 		high = i - 1;
1076 	low = i;
1077 
1078 	return fixp_linear_interpolate(vbat2ri[low].vbat_uv,
1079 				       vbat2ri[low].ri_uohm,
1080 				       vbat2ri[high].vbat_uv,
1081 				       vbat2ri[high].ri_uohm,
1082 				       vbat_uv);
1083 }
1084 EXPORT_SYMBOL_GPL(power_supply_vbat2ri);
1085 
1086 const struct power_supply_maintenance_charge_table *
power_supply_get_maintenance_charging_setting(struct power_supply_battery_info * info,int index)1087 power_supply_get_maintenance_charging_setting(struct power_supply_battery_info *info,
1088 					      int index)
1089 {
1090 	if (index >= info->maintenance_charge_size)
1091 		return NULL;
1092 	return &info->maintenance_charge[index];
1093 }
1094 EXPORT_SYMBOL_GPL(power_supply_get_maintenance_charging_setting);
1095 
1096 /**
1097  * power_supply_ocv2cap_simple() - find the battery capacity
1098  * @table: Pointer to battery OCV lookup table
1099  * @table_len: OCV table length
1100  * @ocv: Current OCV value
1101  *
1102  * This helper function is used to look up battery capacity according to
1103  * current OCV value from one OCV table, and the OCV table must be ordered
1104  * descending.
1105  *
1106  * Return: the battery capacity.
1107  */
power_supply_ocv2cap_simple(const struct power_supply_battery_ocv_table * table,int table_len,int ocv)1108 int power_supply_ocv2cap_simple(const struct power_supply_battery_ocv_table *table,
1109 				int table_len, int ocv)
1110 {
1111 	int i, high, low;
1112 
1113 	for (i = 0; i < table_len; i++)
1114 		if (ocv > table[i].ocv)
1115 			break;
1116 
1117 	/* The library function will deal with high == low */
1118 	if (i == 0)
1119 		high = low = i;
1120 	else if (i == table_len)
1121 		high = low = i - 1;
1122 	else
1123 		high = (low = i) - 1;
1124 
1125 	return fixp_linear_interpolate(table[low].ocv,
1126 				       table[low].capacity,
1127 				       table[high].ocv,
1128 				       table[high].capacity,
1129 				       ocv);
1130 }
1131 EXPORT_SYMBOL_GPL(power_supply_ocv2cap_simple);
1132 
1133 const struct power_supply_battery_ocv_table *
power_supply_find_ocv2cap_table(struct power_supply_battery_info * info,int temp,int * table_len)1134 power_supply_find_ocv2cap_table(struct power_supply_battery_info *info,
1135 				int temp, int *table_len)
1136 {
1137 	int best_temp_diff = INT_MAX, temp_diff;
1138 	u8 i, best_index = 0;
1139 
1140 	if (!info->ocv_table[0])
1141 		return NULL;
1142 
1143 	for (i = 0; i < POWER_SUPPLY_OCV_TEMP_MAX; i++) {
1144 		/* Out of capacity tables */
1145 		if (!info->ocv_table[i])
1146 			break;
1147 
1148 		temp_diff = abs(info->ocv_temp[i] - temp);
1149 
1150 		if (temp_diff < best_temp_diff) {
1151 			best_temp_diff = temp_diff;
1152 			best_index = i;
1153 		}
1154 	}
1155 
1156 	*table_len = info->ocv_table_size[best_index];
1157 	return info->ocv_table[best_index];
1158 }
1159 EXPORT_SYMBOL_GPL(power_supply_find_ocv2cap_table);
1160 
power_supply_batinfo_ocv2cap(struct power_supply_battery_info * info,int ocv,int temp)1161 int power_supply_batinfo_ocv2cap(struct power_supply_battery_info *info,
1162 				 int ocv, int temp)
1163 {
1164 	const struct power_supply_battery_ocv_table *table;
1165 	int table_len;
1166 
1167 	table = power_supply_find_ocv2cap_table(info, temp, &table_len);
1168 	if (!table)
1169 		return -EINVAL;
1170 
1171 	return power_supply_ocv2cap_simple(table, table_len, ocv);
1172 }
1173 EXPORT_SYMBOL_GPL(power_supply_batinfo_ocv2cap);
1174 
power_supply_battery_bti_in_range(struct power_supply_battery_info * info,int resistance)1175 bool power_supply_battery_bti_in_range(struct power_supply_battery_info *info,
1176 				       int resistance)
1177 {
1178 	int low, high;
1179 
1180 	/* Nothing like this can be checked */
1181 	if (info->bti_resistance_ohm <= 0)
1182 		return false;
1183 
1184 	/* This will be extremely strict and unlikely to work */
1185 	if (info->bti_resistance_tolerance <= 0)
1186 		return (info->bti_resistance_ohm == resistance);
1187 
1188 	low = info->bti_resistance_ohm -
1189 		(info->bti_resistance_ohm * info->bti_resistance_tolerance) / 100;
1190 	high = info->bti_resistance_ohm +
1191 		(info->bti_resistance_ohm * info->bti_resistance_tolerance) / 100;
1192 
1193 	return ((resistance >= low) && (resistance <= high));
1194 }
1195 EXPORT_SYMBOL_GPL(power_supply_battery_bti_in_range);
1196 
psy_desc_has_property(const struct power_supply_desc * psy_desc,enum power_supply_property psp)1197 static bool psy_desc_has_property(const struct power_supply_desc *psy_desc,
1198 				  enum power_supply_property psp)
1199 {
1200 	bool found = false;
1201 	int i;
1202 
1203 	for (i = 0; i < psy_desc->num_properties; i++) {
1204 		if (psy_desc->properties[i] == psp) {
1205 			found = true;
1206 			break;
1207 		}
1208 	}
1209 
1210 	return found;
1211 }
1212 
power_supply_ext_has_property(const struct power_supply_ext * psy_ext,enum power_supply_property psp)1213 bool power_supply_ext_has_property(const struct power_supply_ext *psy_ext,
1214 				   enum power_supply_property psp)
1215 {
1216 	int i;
1217 
1218 	for (i = 0; i < psy_ext->num_properties; i++)
1219 		if (psy_ext->properties[i] == psp)
1220 			return true;
1221 
1222 	return false;
1223 }
1224 
power_supply_has_property(struct power_supply * psy,enum power_supply_property psp)1225 bool power_supply_has_property(struct power_supply *psy,
1226 			       enum power_supply_property psp)
1227 {
1228 	struct power_supply_ext_registration *reg;
1229 
1230 	if (psy_desc_has_property(psy->desc, psp))
1231 		return true;
1232 
1233 	if (power_supply_battery_info_has_prop(psy->battery_info, psp))
1234 		return true;
1235 
1236 	power_supply_for_each_extension(reg, psy) {
1237 		if (power_supply_ext_has_property(reg->ext, psp))
1238 			return true;
1239 	}
1240 
1241 	return false;
1242 }
1243 
__power_supply_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val,bool use_extensions)1244 static int __power_supply_get_property(struct power_supply *psy, enum power_supply_property psp,
1245 				       union power_supply_propval *val, bool use_extensions)
1246 {
1247 	struct power_supply_ext_registration *reg;
1248 
1249 	if (atomic_read(&psy->use_cnt) <= 0) {
1250 		if (!psy->initialized)
1251 			return -EAGAIN;
1252 		return -ENODEV;
1253 	}
1254 
1255 	if (use_extensions) {
1256 		scoped_guard(rwsem_read, &psy->extensions_sem) {
1257 			power_supply_for_each_extension(reg, psy) {
1258 				if (!power_supply_ext_has_property(reg->ext, psp))
1259 					continue;
1260 
1261 				return reg->ext->get_property(psy, reg->ext, reg->data, psp, val);
1262 			}
1263 		}
1264 	}
1265 
1266 	if (psy_desc_has_property(psy->desc, psp))
1267 		return psy->desc->get_property(psy, psp, val);
1268 	else if (power_supply_battery_info_has_prop(psy->battery_info, psp))
1269 		return power_supply_battery_info_get_prop(psy->battery_info, psp, val);
1270 	else
1271 		return -EINVAL;
1272 }
1273 
power_supply_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)1274 int power_supply_get_property(struct power_supply *psy, enum power_supply_property psp,
1275 			      union power_supply_propval *val)
1276 {
1277 	return __power_supply_get_property(psy, psp, val, true);
1278 }
1279 EXPORT_SYMBOL_GPL(power_supply_get_property);
1280 
1281 /**
1282  * power_supply_get_property_direct - Read a power supply property without checking for extensions
1283  * @psy: The power supply
1284  * @psp: The power supply property to read
1285  * @val: The resulting value of the power supply property
1286  *
1287  * Read a power supply property without taking into account any power supply extensions registered
1288  * on the given power supply. This is mostly useful for power supply extensions that want to access
1289  * their own power supply as using power_supply_get_property() directly will result in a potential
1290  * deadlock.
1291  *
1292  * Return: 0 on success or negative error code on failure.
1293  */
power_supply_get_property_direct(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)1294 int power_supply_get_property_direct(struct power_supply *psy, enum power_supply_property psp,
1295 				     union power_supply_propval *val)
1296 {
1297         return __power_supply_get_property(psy, psp, val, false);
1298 }
1299 EXPORT_SYMBOL_GPL(power_supply_get_property_direct);
1300 
1301 
__power_supply_set_property(struct power_supply * psy,enum power_supply_property psp,const union power_supply_propval * val,bool use_extensions)1302 static int __power_supply_set_property(struct power_supply *psy, enum power_supply_property psp,
1303 				       const union power_supply_propval *val, bool use_extensions)
1304 {
1305 	struct power_supply_ext_registration *reg;
1306 
1307 	if (atomic_read(&psy->use_cnt) <= 0)
1308 		return -ENODEV;
1309 
1310 	if (use_extensions) {
1311 		scoped_guard(rwsem_read, &psy->extensions_sem) {
1312 			power_supply_for_each_extension(reg, psy) {
1313 				if (!power_supply_ext_has_property(reg->ext, psp))
1314 					continue;
1315 
1316 				if (reg->ext->set_property)
1317 					return reg->ext->set_property(psy, reg->ext, reg->data,
1318 								      psp, val);
1319 				else
1320 					return -ENODEV;
1321 			}
1322 		}
1323 	}
1324 
1325 	if (!psy->desc->set_property)
1326 		return -ENODEV;
1327 
1328 	return psy->desc->set_property(psy, psp, val);
1329 }
1330 
power_supply_set_property(struct power_supply * psy,enum power_supply_property psp,const union power_supply_propval * val)1331 int power_supply_set_property(struct power_supply *psy, enum power_supply_property psp,
1332 			      const union power_supply_propval *val)
1333 {
1334 	return __power_supply_set_property(psy, psp, val, true);
1335 }
1336 EXPORT_SYMBOL_GPL(power_supply_set_property);
1337 
1338 /**
1339  * power_supply_set_property_direct - Write a power supply property without checking for extensions
1340  * @psy: The power supply
1341  * @psp: The power supply property to write
1342  * @val: The value to write to the power supply property
1343  *
1344  * Write a power supply property without taking into account any power supply extensions registered
1345  * on the given power supply. This is mostly useful for power supply extensions that want to access
1346  * their own power supply as using power_supply_set_property() directly will result in a potential
1347  * deadlock.
1348  *
1349  * Return: 0 on success or negative error code on failure.
1350  */
power_supply_set_property_direct(struct power_supply * psy,enum power_supply_property psp,const union power_supply_propval * val)1351 int power_supply_set_property_direct(struct power_supply *psy, enum power_supply_property psp,
1352 				     const union power_supply_propval *val)
1353 {
1354 	return __power_supply_set_property(psy, psp, val, false);
1355 }
1356 EXPORT_SYMBOL_GPL(power_supply_set_property_direct);
1357 
power_supply_property_is_writeable(struct power_supply * psy,enum power_supply_property psp)1358 int power_supply_property_is_writeable(struct power_supply *psy,
1359 					enum power_supply_property psp)
1360 {
1361 	struct power_supply_ext_registration *reg;
1362 
1363 	power_supply_for_each_extension(reg, psy) {
1364 		if (power_supply_ext_has_property(reg->ext, psp)) {
1365 			if (reg->ext->property_is_writeable)
1366 				return reg->ext->property_is_writeable(psy, reg->ext,
1367 								       reg->data, psp);
1368 			else
1369 				return 0;
1370 		}
1371 	}
1372 
1373 	if (!psy->desc->property_is_writeable)
1374 		return 0;
1375 
1376 	return psy->desc->property_is_writeable(psy, psp);
1377 }
1378 
power_supply_external_power_changed(struct power_supply * psy)1379 void power_supply_external_power_changed(struct power_supply *psy)
1380 {
1381 	if (atomic_read(&psy->use_cnt) <= 0 ||
1382 			!psy->desc->external_power_changed)
1383 		return;
1384 
1385 	psy->desc->external_power_changed(psy);
1386 }
1387 EXPORT_SYMBOL_GPL(power_supply_external_power_changed);
1388 
power_supply_powers(struct power_supply * psy,struct device * dev)1389 int power_supply_powers(struct power_supply *psy, struct device *dev)
1390 {
1391 	return sysfs_create_link(&psy->dev.kobj, &dev->kobj, "powers");
1392 }
1393 EXPORT_SYMBOL_GPL(power_supply_powers);
1394 
power_supply_update_sysfs_and_hwmon(struct power_supply * psy)1395 static int power_supply_update_sysfs_and_hwmon(struct power_supply *psy)
1396 {
1397 	unsigned long flags;
1398 
1399 	spin_lock_irqsave(&psy->changed_lock, flags);
1400 	psy->update_groups = true;
1401 	spin_unlock_irqrestore(&psy->changed_lock, flags);
1402 
1403 	power_supply_changed(psy);
1404 
1405 	power_supply_remove_hwmon_sysfs(psy);
1406 	return power_supply_add_hwmon_sysfs(psy);
1407 }
1408 
power_supply_register_extension(struct power_supply * psy,const struct power_supply_ext * ext,struct device * dev,void * data)1409 int power_supply_register_extension(struct power_supply *psy, const struct power_supply_ext *ext,
1410 				    struct device *dev, void *data)
1411 {
1412 	struct power_supply_ext_registration *reg;
1413 	size_t i;
1414 	int ret;
1415 
1416 	if (!psy || !dev || !ext || !ext->name || !ext->properties || !ext->num_properties)
1417 		return -EINVAL;
1418 
1419 	guard(rwsem_write)(&psy->extensions_sem);
1420 
1421 	power_supply_for_each_extension(reg, psy)
1422 		if (strcmp(ext->name, reg->ext->name) == 0)
1423 			return -EEXIST;
1424 
1425 	for (i = 0; i < ext->num_properties; i++)
1426 		if (power_supply_has_property(psy, ext->properties[i]))
1427 			return -EEXIST;
1428 
1429 	reg = kmalloc(sizeof(*reg), GFP_KERNEL);
1430 	if (!reg)
1431 		return -ENOMEM;
1432 
1433 	reg->ext = ext;
1434 	reg->dev = dev;
1435 	reg->data = data;
1436 	list_add(&reg->list_head, &psy->extensions);
1437 
1438 	ret = power_supply_sysfs_add_extension(psy, ext, dev);
1439 	if (ret)
1440 		goto sysfs_add_failed;
1441 
1442 	ret = power_supply_update_sysfs_and_hwmon(psy);
1443 	if (ret)
1444 		goto sysfs_hwmon_failed;
1445 
1446 	return 0;
1447 
1448 sysfs_hwmon_failed:
1449 	power_supply_sysfs_remove_extension(psy, ext);
1450 sysfs_add_failed:
1451 	list_del(&reg->list_head);
1452 	kfree(reg);
1453 	return ret;
1454 }
1455 EXPORT_SYMBOL_GPL(power_supply_register_extension);
1456 
power_supply_unregister_extension(struct power_supply * psy,const struct power_supply_ext * ext)1457 void power_supply_unregister_extension(struct power_supply *psy, const struct power_supply_ext *ext)
1458 {
1459 	struct power_supply_ext_registration *reg;
1460 
1461 	guard(rwsem_write)(&psy->extensions_sem);
1462 
1463 	power_supply_for_each_extension(reg, psy) {
1464 		if (reg->ext == ext) {
1465 			list_del(&reg->list_head);
1466 			power_supply_sysfs_remove_extension(psy, ext);
1467 			kfree(reg);
1468 			power_supply_update_sysfs_and_hwmon(psy);
1469 			return;
1470 		}
1471 	}
1472 
1473 	dev_warn(&psy->dev, "Trying to unregister invalid extension");
1474 }
1475 EXPORT_SYMBOL_GPL(power_supply_unregister_extension);
1476 
power_supply_dev_release(struct device * dev)1477 static void power_supply_dev_release(struct device *dev)
1478 {
1479 	struct power_supply *psy = to_power_supply(dev);
1480 
1481 	dev_dbg(dev, "%s\n", __func__);
1482 	kfree(psy);
1483 }
1484 
power_supply_reg_notifier(struct notifier_block * nb)1485 int power_supply_reg_notifier(struct notifier_block *nb)
1486 {
1487 	return blocking_notifier_chain_register(&power_supply_notifier, nb);
1488 }
1489 EXPORT_SYMBOL_GPL(power_supply_reg_notifier);
1490 
power_supply_unreg_notifier(struct notifier_block * nb)1491 void power_supply_unreg_notifier(struct notifier_block *nb)
1492 {
1493 	blocking_notifier_chain_unregister(&power_supply_notifier, nb);
1494 }
1495 EXPORT_SYMBOL_GPL(power_supply_unreg_notifier);
1496 
1497 #ifdef CONFIG_THERMAL
power_supply_read_temp(struct thermal_zone_device * tzd,int * temp)1498 static int power_supply_read_temp(struct thermal_zone_device *tzd,
1499 		int *temp)
1500 {
1501 	struct power_supply *psy;
1502 	union power_supply_propval val;
1503 	int ret;
1504 
1505 	WARN_ON(tzd == NULL);
1506 	psy = thermal_zone_device_priv(tzd);
1507 	ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_TEMP, &val);
1508 	if (ret)
1509 		return ret;
1510 
1511 	/* Convert tenths of degree Celsius to milli degree Celsius. */
1512 	*temp = val.intval * 100;
1513 
1514 	return ret;
1515 }
1516 
1517 static const struct thermal_zone_device_ops psy_tzd_ops = {
1518 	.get_temp = power_supply_read_temp,
1519 };
1520 
psy_register_thermal(struct power_supply * psy)1521 static int psy_register_thermal(struct power_supply *psy)
1522 {
1523 	int ret;
1524 
1525 	if (psy->desc->no_thermal)
1526 		return 0;
1527 
1528 	/* Register battery zone device psy reports temperature */
1529 	if (psy_desc_has_property(psy->desc, POWER_SUPPLY_PROP_TEMP)) {
1530 		/* Prefer our hwmon device and avoid duplicates */
1531 		struct thermal_zone_params tzp = {
1532 			.no_hwmon = IS_ENABLED(CONFIG_POWER_SUPPLY_HWMON)
1533 		};
1534 		psy->tzd = thermal_tripless_zone_device_register(psy->desc->name,
1535 				psy, &psy_tzd_ops, &tzp);
1536 		if (IS_ERR(psy->tzd))
1537 			return PTR_ERR(psy->tzd);
1538 		ret = thermal_zone_device_enable(psy->tzd);
1539 		if (ret)
1540 			thermal_zone_device_unregister(psy->tzd);
1541 		return ret;
1542 	}
1543 
1544 	return 0;
1545 }
1546 
psy_unregister_thermal(struct power_supply * psy)1547 static void psy_unregister_thermal(struct power_supply *psy)
1548 {
1549 	if (IS_ERR_OR_NULL(psy->tzd))
1550 		return;
1551 	thermal_zone_device_unregister(psy->tzd);
1552 }
1553 
1554 #else
psy_register_thermal(struct power_supply * psy)1555 static int psy_register_thermal(struct power_supply *psy)
1556 {
1557 	return 0;
1558 }
1559 
psy_unregister_thermal(struct power_supply * psy)1560 static void psy_unregister_thermal(struct power_supply *psy)
1561 {
1562 }
1563 #endif
1564 
1565 static struct power_supply *__must_check
__power_supply_register(struct device * parent,const struct power_supply_desc * desc,const struct power_supply_config * cfg)1566 __power_supply_register(struct device *parent,
1567 				   const struct power_supply_desc *desc,
1568 				   const struct power_supply_config *cfg)
1569 {
1570 	struct device *dev;
1571 	struct power_supply *psy;
1572 	int rc;
1573 
1574 	if (!desc || !desc->name || !desc->properties || !desc->num_properties)
1575 		return ERR_PTR(-EINVAL);
1576 
1577 	if (!parent)
1578 		pr_warn("%s: Expected proper parent device for '%s'\n",
1579 			__func__, desc->name);
1580 
1581 	psy = kzalloc(sizeof(*psy), GFP_KERNEL);
1582 	if (!psy)
1583 		return ERR_PTR(-ENOMEM);
1584 
1585 	dev = &psy->dev;
1586 
1587 	device_initialize(dev);
1588 
1589 	dev->class = &power_supply_class;
1590 	dev->type = &power_supply_dev_type;
1591 	dev->parent = parent;
1592 	dev->release = power_supply_dev_release;
1593 	dev_set_drvdata(dev, psy);
1594 	psy->desc = desc;
1595 	if (cfg) {
1596 		device_set_node(dev, cfg->fwnode);
1597 		dev->groups = cfg->attr_grp;
1598 		psy->drv_data = cfg->drv_data;
1599 		psy->supplied_to = cfg->supplied_to;
1600 		psy->num_supplicants = cfg->num_supplicants;
1601 	}
1602 
1603 	rc = dev_set_name(dev, "%s", desc->name);
1604 	if (rc)
1605 		goto dev_set_name_failed;
1606 
1607 	INIT_WORK(&psy->changed_work, power_supply_changed_work);
1608 	INIT_DELAYED_WORK(&psy->deferred_register_work,
1609 			  power_supply_deferred_register_work);
1610 
1611 	rc = power_supply_check_supplies(psy);
1612 	if (rc) {
1613 		dev_dbg(dev, "Not all required supplies found, defer probe\n");
1614 		goto check_supplies_failed;
1615 	}
1616 
1617 	/*
1618 	 * Expose constant battery info, if it is available. While there are
1619 	 * some chargers accessing constant battery data, we only want to
1620 	 * expose battery data to userspace for battery devices.
1621 	 */
1622 	if (desc->type == POWER_SUPPLY_TYPE_BATTERY) {
1623 		rc = power_supply_get_battery_info(psy, &psy->battery_info);
1624 		if (rc && rc != -ENODEV && rc != -ENOENT)
1625 			goto check_supplies_failed;
1626 	}
1627 
1628 	spin_lock_init(&psy->changed_lock);
1629 	init_rwsem(&psy->extensions_sem);
1630 	INIT_LIST_HEAD(&psy->extensions);
1631 
1632 	rc = device_add(dev);
1633 	if (rc)
1634 		goto device_add_failed;
1635 
1636 	rc = device_init_wakeup(dev, cfg ? !cfg->no_wakeup_source : true);
1637 	if (rc)
1638 		goto wakeup_init_failed;
1639 
1640 	rc = psy_register_thermal(psy);
1641 	if (rc)
1642 		goto register_thermal_failed;
1643 
1644 	rc = power_supply_create_triggers(psy);
1645 	if (rc)
1646 		goto create_triggers_failed;
1647 
1648 	scoped_guard(rwsem_read, &psy->extensions_sem) {
1649 		rc = power_supply_add_hwmon_sysfs(psy);
1650 		if (rc)
1651 			goto add_hwmon_sysfs_failed;
1652 	}
1653 
1654 	/*
1655 	 * Update use_cnt after any uevents (most notably from device_add()).
1656 	 * We are here still during driver's probe but
1657 	 * the power_supply_uevent() calls back driver's get_property
1658 	 * method so:
1659 	 * 1. Driver did not assigned the returned struct power_supply,
1660 	 * 2. Driver could not finish initialization (anything in its probe
1661 	 *    after calling power_supply_register()).
1662 	 */
1663 	atomic_inc(&psy->use_cnt);
1664 	psy->initialized = true;
1665 
1666 	queue_delayed_work(system_power_efficient_wq,
1667 			   &psy->deferred_register_work,
1668 			   POWER_SUPPLY_DEFERRED_REGISTER_TIME);
1669 
1670 	return psy;
1671 
1672 add_hwmon_sysfs_failed:
1673 	power_supply_remove_triggers(psy);
1674 create_triggers_failed:
1675 	psy_unregister_thermal(psy);
1676 register_thermal_failed:
1677 wakeup_init_failed:
1678 	device_del(dev);
1679 device_add_failed:
1680 check_supplies_failed:
1681 dev_set_name_failed:
1682 	put_device(dev);
1683 	return ERR_PTR(rc);
1684 }
1685 
1686 /**
1687  * power_supply_register() - Register new power supply
1688  * @parent:	Device to be a parent of power supply's device, usually
1689  *		the device which probe function calls this
1690  * @desc:	Description of power supply, must be valid through whole
1691  *		lifetime of this power supply
1692  * @cfg:	Run-time specific configuration accessed during registering,
1693  *		may be NULL
1694  *
1695  * Return: A pointer to newly allocated power_supply on success
1696  * or ERR_PTR otherwise.
1697  * Use power_supply_unregister() on returned power_supply pointer to release
1698  * resources.
1699  */
power_supply_register(struct device * parent,const struct power_supply_desc * desc,const struct power_supply_config * cfg)1700 struct power_supply *__must_check power_supply_register(struct device *parent,
1701 		const struct power_supply_desc *desc,
1702 		const struct power_supply_config *cfg)
1703 {
1704 	return __power_supply_register(parent, desc, cfg);
1705 }
1706 EXPORT_SYMBOL_GPL(power_supply_register);
1707 
devm_power_supply_release(struct device * dev,void * res)1708 static void devm_power_supply_release(struct device *dev, void *res)
1709 {
1710 	struct power_supply **psy = res;
1711 
1712 	power_supply_unregister(*psy);
1713 }
1714 
1715 /**
1716  * devm_power_supply_register() - Register managed power supply
1717  * @parent:	Device to be a parent of power supply's device, usually
1718  *		the device which probe function calls this
1719  * @desc:	Description of power supply, must be valid through whole
1720  *		lifetime of this power supply
1721  * @cfg:	Run-time specific configuration accessed during registering,
1722  *		may be NULL
1723  *
1724  * Return: A pointer to newly allocated power_supply on success
1725  * or ERR_PTR otherwise.
1726  * The returned power_supply pointer will be automatically unregistered
1727  * on driver detach.
1728  */
1729 struct power_supply *__must_check
devm_power_supply_register(struct device * parent,const struct power_supply_desc * desc,const struct power_supply_config * cfg)1730 devm_power_supply_register(struct device *parent,
1731 		const struct power_supply_desc *desc,
1732 		const struct power_supply_config *cfg)
1733 {
1734 	struct power_supply **ptr, *psy;
1735 
1736 	ptr = devres_alloc(devm_power_supply_release, sizeof(*ptr), GFP_KERNEL);
1737 
1738 	if (!ptr)
1739 		return ERR_PTR(-ENOMEM);
1740 	psy = __power_supply_register(parent, desc, cfg);
1741 	if (IS_ERR(psy)) {
1742 		devres_free(ptr);
1743 	} else {
1744 		*ptr = psy;
1745 		devres_add(parent, ptr);
1746 	}
1747 	return psy;
1748 }
1749 EXPORT_SYMBOL_GPL(devm_power_supply_register);
1750 
1751 /**
1752  * power_supply_unregister() - Remove this power supply from system
1753  * @psy:	Pointer to power supply to unregister
1754  *
1755  * Remove this power supply from the system. The resources of power supply
1756  * will be freed here or on last power_supply_put() call.
1757  */
power_supply_unregister(struct power_supply * psy)1758 void power_supply_unregister(struct power_supply *psy)
1759 {
1760 	WARN_ON(atomic_dec_return(&psy->use_cnt));
1761 	psy->removing = true;
1762 	cancel_work_sync(&psy->changed_work);
1763 	cancel_delayed_work_sync(&psy->deferred_register_work);
1764 	sysfs_remove_link(&psy->dev.kobj, "powers");
1765 	power_supply_remove_hwmon_sysfs(psy);
1766 	power_supply_remove_triggers(psy);
1767 	psy_unregister_thermal(psy);
1768 	device_init_wakeup(&psy->dev, false);
1769 	device_unregister(&psy->dev);
1770 }
1771 EXPORT_SYMBOL_GPL(power_supply_unregister);
1772 
power_supply_get_drvdata(struct power_supply * psy)1773 void *power_supply_get_drvdata(struct power_supply *psy)
1774 {
1775 	return psy->drv_data;
1776 }
1777 EXPORT_SYMBOL_GPL(power_supply_get_drvdata);
1778 
power_supply_class_init(void)1779 static int __init power_supply_class_init(void)
1780 {
1781 	power_supply_init_attrs();
1782 	return class_register(&power_supply_class);
1783 }
1784 
power_supply_class_exit(void)1785 static void __exit power_supply_class_exit(void)
1786 {
1787 	class_unregister(&power_supply_class);
1788 }
1789 
1790 subsys_initcall(power_supply_class_init);
1791 module_exit(power_supply_class_exit);
1792 
1793 MODULE_DESCRIPTION("Universal power supply monitor class");
1794 MODULE_AUTHOR("Ian Molton <spyro@f2s.com>");
1795 MODULE_AUTHOR("Szabolcs Gyurko");
1796 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");
1797