1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Sysfs interface for the universal power supply monitor class
4  *
5  *  Copyright © 2007  David Woodhouse <[email protected]>
6  *  Copyright © 2007  Anton Vorontsov <[email protected]>
7  *  Copyright © 2004  Szabolcs Gyurko
8  *  Copyright © 2003  Ian Molton <[email protected]>
9  *
10  *  Modified: 2004, Oct     Szabolcs Gyurko
11  */
12 
13 #include <linux/ctype.h>
14 #include <linux/device.h>
15 #include <linux/power_supply.h>
16 #include <linux/slab.h>
17 #include <linux/stat.h>
18 #include <linux/string_helpers.h>
19 
20 #include "power_supply.h"
21 
22 #define MAX_PROP_NAME_LEN 30
23 
24 struct power_supply_attr {
25 	const char *prop_name;
26 	char attr_name[MAX_PROP_NAME_LEN + 1];
27 	struct device_attribute dev_attr;
28 	const char * const *text_values;
29 	int text_values_len;
30 };
31 
32 #define _POWER_SUPPLY_ATTR(_name, _text, _len)	\
33 [POWER_SUPPLY_PROP_ ## _name] =			\
34 {						\
35 	.prop_name = #_name,			\
36 	.attr_name = #_name "\0",		\
37 	.text_values = _text,			\
38 	.text_values_len = _len,		\
39 }
40 
41 #define POWER_SUPPLY_ATTR(_name) _POWER_SUPPLY_ATTR(_name, NULL, 0)
42 #define _POWER_SUPPLY_ENUM_ATTR(_name, _text)	\
43 	_POWER_SUPPLY_ATTR(_name, _text, ARRAY_SIZE(_text))
44 #define POWER_SUPPLY_ENUM_ATTR(_name)	\
45 	_POWER_SUPPLY_ENUM_ATTR(_name, POWER_SUPPLY_ ## _name ## _TEXT)
46 
47 static const char * const POWER_SUPPLY_TYPE_TEXT[] = {
48 	[POWER_SUPPLY_TYPE_UNKNOWN]		= "Unknown",
49 	[POWER_SUPPLY_TYPE_BATTERY]		= "Battery",
50 	[POWER_SUPPLY_TYPE_UPS]			= "UPS",
51 	[POWER_SUPPLY_TYPE_MAINS]		= "Mains",
52 	[POWER_SUPPLY_TYPE_USB]			= "USB",
53 	[POWER_SUPPLY_TYPE_USB_DCP]		= "USB_DCP",
54 	[POWER_SUPPLY_TYPE_USB_CDP]		= "USB_CDP",
55 	[POWER_SUPPLY_TYPE_USB_ACA]		= "USB_ACA",
56 	[POWER_SUPPLY_TYPE_USB_TYPE_C]		= "USB_C",
57 	[POWER_SUPPLY_TYPE_USB_PD]		= "USB_PD",
58 	[POWER_SUPPLY_TYPE_USB_PD_DRP]		= "USB_PD_DRP",
59 	[POWER_SUPPLY_TYPE_APPLE_BRICK_ID]	= "BrickID",
60 	[POWER_SUPPLY_TYPE_WIRELESS]		= "Wireless",
61 };
62 
63 static const char * const POWER_SUPPLY_USB_TYPE_TEXT[] = {
64 	[POWER_SUPPLY_USB_TYPE_UNKNOWN]		= "Unknown",
65 	[POWER_SUPPLY_USB_TYPE_SDP]		= "SDP",
66 	[POWER_SUPPLY_USB_TYPE_DCP]		= "DCP",
67 	[POWER_SUPPLY_USB_TYPE_CDP]		= "CDP",
68 	[POWER_SUPPLY_USB_TYPE_ACA]		= "ACA",
69 	[POWER_SUPPLY_USB_TYPE_C]		= "C",
70 	[POWER_SUPPLY_USB_TYPE_PD]		= "PD",
71 	[POWER_SUPPLY_USB_TYPE_PD_DRP]		= "PD_DRP",
72 	[POWER_SUPPLY_USB_TYPE_PD_PPS]		= "PD_PPS",
73 	[POWER_SUPPLY_USB_TYPE_APPLE_BRICK_ID]	= "BrickID",
74 };
75 
76 static const char * const POWER_SUPPLY_STATUS_TEXT[] = {
77 	[POWER_SUPPLY_STATUS_UNKNOWN]		= "Unknown",
78 	[POWER_SUPPLY_STATUS_CHARGING]		= "Charging",
79 	[POWER_SUPPLY_STATUS_DISCHARGING]	= "Discharging",
80 	[POWER_SUPPLY_STATUS_NOT_CHARGING]	= "Not charging",
81 	[POWER_SUPPLY_STATUS_FULL]		= "Full",
82 };
83 
84 static const char * const POWER_SUPPLY_CHARGE_TYPE_TEXT[] = {
85 	[POWER_SUPPLY_CHARGE_TYPE_UNKNOWN]	= "Unknown",
86 	[POWER_SUPPLY_CHARGE_TYPE_NONE]		= "N/A",
87 	[POWER_SUPPLY_CHARGE_TYPE_TRICKLE]	= "Trickle",
88 	[POWER_SUPPLY_CHARGE_TYPE_FAST]		= "Fast",
89 	[POWER_SUPPLY_CHARGE_TYPE_STANDARD]	= "Standard",
90 	[POWER_SUPPLY_CHARGE_TYPE_ADAPTIVE]	= "Adaptive",
91 	[POWER_SUPPLY_CHARGE_TYPE_CUSTOM]	= "Custom",
92 	[POWER_SUPPLY_CHARGE_TYPE_LONGLIFE]	= "Long Life",
93 	[POWER_SUPPLY_CHARGE_TYPE_BYPASS]	= "Bypass",
94 };
95 
96 static const char * const POWER_SUPPLY_HEALTH_TEXT[] = {
97 	[POWER_SUPPLY_HEALTH_UNKNOWN]		    = "Unknown",
98 	[POWER_SUPPLY_HEALTH_GOOD]		    = "Good",
99 	[POWER_SUPPLY_HEALTH_OVERHEAT]		    = "Overheat",
100 	[POWER_SUPPLY_HEALTH_DEAD]		    = "Dead",
101 	[POWER_SUPPLY_HEALTH_OVERVOLTAGE]	    = "Over voltage",
102 	[POWER_SUPPLY_HEALTH_UNDERVOLTAGE]	    = "Under voltage",
103 	[POWER_SUPPLY_HEALTH_UNSPEC_FAILURE]	    = "Unspecified failure",
104 	[POWER_SUPPLY_HEALTH_COLD]		    = "Cold",
105 	[POWER_SUPPLY_HEALTH_WATCHDOG_TIMER_EXPIRE] = "Watchdog timer expire",
106 	[POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE]   = "Safety timer expire",
107 	[POWER_SUPPLY_HEALTH_OVERCURRENT]	    = "Over current",
108 	[POWER_SUPPLY_HEALTH_CALIBRATION_REQUIRED]  = "Calibration required",
109 	[POWER_SUPPLY_HEALTH_WARM]		    = "Warm",
110 	[POWER_SUPPLY_HEALTH_COOL]		    = "Cool",
111 	[POWER_SUPPLY_HEALTH_HOT]		    = "Hot",
112 	[POWER_SUPPLY_HEALTH_NO_BATTERY]	    = "No battery",
113 };
114 
115 static const char * const POWER_SUPPLY_TECHNOLOGY_TEXT[] = {
116 	[POWER_SUPPLY_TECHNOLOGY_UNKNOWN]	= "Unknown",
117 	[POWER_SUPPLY_TECHNOLOGY_NiMH]		= "NiMH",
118 	[POWER_SUPPLY_TECHNOLOGY_LION]		= "Li-ion",
119 	[POWER_SUPPLY_TECHNOLOGY_LIPO]		= "Li-poly",
120 	[POWER_SUPPLY_TECHNOLOGY_LiFe]		= "LiFe",
121 	[POWER_SUPPLY_TECHNOLOGY_NiCd]		= "NiCd",
122 	[POWER_SUPPLY_TECHNOLOGY_LiMn]		= "LiMn",
123 };
124 
125 static const char * const POWER_SUPPLY_CAPACITY_LEVEL_TEXT[] = {
126 	[POWER_SUPPLY_CAPACITY_LEVEL_UNKNOWN]	= "Unknown",
127 	[POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL]	= "Critical",
128 	[POWER_SUPPLY_CAPACITY_LEVEL_LOW]	= "Low",
129 	[POWER_SUPPLY_CAPACITY_LEVEL_NORMAL]	= "Normal",
130 	[POWER_SUPPLY_CAPACITY_LEVEL_HIGH]	= "High",
131 	[POWER_SUPPLY_CAPACITY_LEVEL_FULL]	= "Full",
132 };
133 
134 static const char * const POWER_SUPPLY_SCOPE_TEXT[] = {
135 	[POWER_SUPPLY_SCOPE_UNKNOWN]	= "Unknown",
136 	[POWER_SUPPLY_SCOPE_SYSTEM]	= "System",
137 	[POWER_SUPPLY_SCOPE_DEVICE]	= "Device",
138 };
139 
140 static const char * const POWER_SUPPLY_CHARGE_BEHAVIOUR_TEXT[] = {
141 	[POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO]		= "auto",
142 	[POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE]	= "inhibit-charge",
143 	[POWER_SUPPLY_CHARGE_BEHAVIOUR_FORCE_DISCHARGE]	= "force-discharge",
144 };
145 
146 static struct power_supply_attr power_supply_attrs[] __ro_after_init = {
147 	/* Properties of type `int' */
148 	POWER_SUPPLY_ENUM_ATTR(STATUS),
149 	POWER_SUPPLY_ENUM_ATTR(CHARGE_TYPE),
150 	POWER_SUPPLY_ENUM_ATTR(HEALTH),
151 	POWER_SUPPLY_ATTR(PRESENT),
152 	POWER_SUPPLY_ATTR(ONLINE),
153 	POWER_SUPPLY_ATTR(AUTHENTIC),
154 	POWER_SUPPLY_ENUM_ATTR(TECHNOLOGY),
155 	POWER_SUPPLY_ATTR(CYCLE_COUNT),
156 	POWER_SUPPLY_ATTR(VOLTAGE_MAX),
157 	POWER_SUPPLY_ATTR(VOLTAGE_MIN),
158 	POWER_SUPPLY_ATTR(VOLTAGE_MAX_DESIGN),
159 	POWER_SUPPLY_ATTR(VOLTAGE_MIN_DESIGN),
160 	POWER_SUPPLY_ATTR(VOLTAGE_NOW),
161 	POWER_SUPPLY_ATTR(VOLTAGE_AVG),
162 	POWER_SUPPLY_ATTR(VOLTAGE_OCV),
163 	POWER_SUPPLY_ATTR(VOLTAGE_BOOT),
164 	POWER_SUPPLY_ATTR(CURRENT_MAX),
165 	POWER_SUPPLY_ATTR(CURRENT_NOW),
166 	POWER_SUPPLY_ATTR(CURRENT_AVG),
167 	POWER_SUPPLY_ATTR(CURRENT_BOOT),
168 	POWER_SUPPLY_ATTR(POWER_NOW),
169 	POWER_SUPPLY_ATTR(POWER_AVG),
170 	POWER_SUPPLY_ATTR(CHARGE_FULL_DESIGN),
171 	POWER_SUPPLY_ATTR(CHARGE_EMPTY_DESIGN),
172 	POWER_SUPPLY_ATTR(CHARGE_FULL),
173 	POWER_SUPPLY_ATTR(CHARGE_EMPTY),
174 	POWER_SUPPLY_ATTR(CHARGE_NOW),
175 	POWER_SUPPLY_ATTR(CHARGE_AVG),
176 	POWER_SUPPLY_ATTR(CHARGE_COUNTER),
177 	POWER_SUPPLY_ATTR(CONSTANT_CHARGE_CURRENT),
178 	POWER_SUPPLY_ATTR(CONSTANT_CHARGE_CURRENT_MAX),
179 	POWER_SUPPLY_ATTR(CONSTANT_CHARGE_VOLTAGE),
180 	POWER_SUPPLY_ATTR(CONSTANT_CHARGE_VOLTAGE_MAX),
181 	POWER_SUPPLY_ATTR(CHARGE_CONTROL_LIMIT),
182 	POWER_SUPPLY_ATTR(CHARGE_CONTROL_LIMIT_MAX),
183 	POWER_SUPPLY_ATTR(CHARGE_CONTROL_START_THRESHOLD),
184 	POWER_SUPPLY_ATTR(CHARGE_CONTROL_END_THRESHOLD),
185 	POWER_SUPPLY_ENUM_ATTR(CHARGE_BEHAVIOUR),
186 	/* Same enum value texts as "charge_type" without the 's' at the end */
187 	_POWER_SUPPLY_ENUM_ATTR(CHARGE_TYPES, POWER_SUPPLY_CHARGE_TYPE_TEXT),
188 	POWER_SUPPLY_ATTR(INPUT_CURRENT_LIMIT),
189 	POWER_SUPPLY_ATTR(INPUT_VOLTAGE_LIMIT),
190 	POWER_SUPPLY_ATTR(INPUT_POWER_LIMIT),
191 	POWER_SUPPLY_ATTR(ENERGY_FULL_DESIGN),
192 	POWER_SUPPLY_ATTR(ENERGY_EMPTY_DESIGN),
193 	POWER_SUPPLY_ATTR(ENERGY_FULL),
194 	POWER_SUPPLY_ATTR(ENERGY_EMPTY),
195 	POWER_SUPPLY_ATTR(ENERGY_NOW),
196 	POWER_SUPPLY_ATTR(ENERGY_AVG),
197 	POWER_SUPPLY_ATTR(CAPACITY),
198 	POWER_SUPPLY_ATTR(CAPACITY_ALERT_MIN),
199 	POWER_SUPPLY_ATTR(CAPACITY_ALERT_MAX),
200 	POWER_SUPPLY_ATTR(CAPACITY_ERROR_MARGIN),
201 	POWER_SUPPLY_ENUM_ATTR(CAPACITY_LEVEL),
202 	POWER_SUPPLY_ATTR(TEMP),
203 	POWER_SUPPLY_ATTR(TEMP_MAX),
204 	POWER_SUPPLY_ATTR(TEMP_MIN),
205 	POWER_SUPPLY_ATTR(TEMP_ALERT_MIN),
206 	POWER_SUPPLY_ATTR(TEMP_ALERT_MAX),
207 	POWER_SUPPLY_ATTR(TEMP_AMBIENT),
208 	POWER_SUPPLY_ATTR(TEMP_AMBIENT_ALERT_MIN),
209 	POWER_SUPPLY_ATTR(TEMP_AMBIENT_ALERT_MAX),
210 	POWER_SUPPLY_ATTR(TIME_TO_EMPTY_NOW),
211 	POWER_SUPPLY_ATTR(TIME_TO_EMPTY_AVG),
212 	POWER_SUPPLY_ATTR(TIME_TO_FULL_NOW),
213 	POWER_SUPPLY_ATTR(TIME_TO_FULL_AVG),
214 	POWER_SUPPLY_ENUM_ATTR(TYPE),
215 	POWER_SUPPLY_ENUM_ATTR(USB_TYPE),
216 	POWER_SUPPLY_ENUM_ATTR(SCOPE),
217 	POWER_SUPPLY_ATTR(PRECHARGE_CURRENT),
218 	POWER_SUPPLY_ATTR(CHARGE_TERM_CURRENT),
219 	POWER_SUPPLY_ATTR(CALIBRATE),
220 	POWER_SUPPLY_ATTR(MANUFACTURE_YEAR),
221 	POWER_SUPPLY_ATTR(MANUFACTURE_MONTH),
222 	POWER_SUPPLY_ATTR(MANUFACTURE_DAY),
223 	/* Properties of type `const char *' */
224 	POWER_SUPPLY_ATTR(MODEL_NAME),
225 	POWER_SUPPLY_ATTR(MANUFACTURER),
226 	POWER_SUPPLY_ATTR(SERIAL_NUMBER),
227 };
228 #define POWER_SUPPLY_ATTR_CNT ARRAY_SIZE(power_supply_attrs)
229 
230 static struct attribute *
231 __power_supply_attrs[POWER_SUPPLY_ATTR_CNT + 1] __ro_after_init;
232 
to_ps_attr(struct device_attribute * attr)233 static const struct power_supply_attr *to_ps_attr(struct device_attribute *attr)
234 {
235 	return container_of(attr, struct power_supply_attr, dev_attr);
236 }
237 
dev_attr_psp(struct device_attribute * attr)238 static enum power_supply_property dev_attr_psp(struct device_attribute *attr)
239 {
240 	return  to_ps_attr(attr) - power_supply_attrs;
241 }
242 
power_supply_escape_spaces(const char * str,char * buf,size_t bufsize)243 static void power_supply_escape_spaces(const char *str, char *buf, size_t bufsize)
244 {
245 	strscpy(buf, str, bufsize);
246 	strreplace(buf, ' ', '_');
247 }
248 
power_supply_match_string(const char * const * array,size_t n,const char * s)249 static int power_supply_match_string(const char * const *array, size_t n, const char *s)
250 {
251 	int ret;
252 
253 	/* First try an exact match */
254 	ret = __sysfs_match_string(array, n, s);
255 	if (ret >= 0)
256 		return ret;
257 
258 	/* Second round, try matching with spaces replaced by '_' */
259 	for (size_t i = 0; i < n; i++) {
260 		char buf[32];
261 
262 		power_supply_escape_spaces(array[i], buf, sizeof(buf));
263 		if (sysfs_streq(buf, s))
264 			return i;
265 	}
266 
267 	return -EINVAL;
268 }
269 
power_supply_show_enum_with_available(struct device * dev,const char * const labels[],int label_count,unsigned int available_values,int value,char * buf)270 static ssize_t power_supply_show_enum_with_available(
271 			struct device *dev, const char * const labels[], int label_count,
272 			unsigned int available_values, int value, char *buf)
273 {
274 	bool match = false, available, active;
275 	char escaped_label[32];
276 	ssize_t count = 0;
277 	int i;
278 
279 	for (i = 0; i < label_count; i++) {
280 		available = available_values & BIT(i);
281 		active = i == value;
282 		power_supply_escape_spaces(labels[i], escaped_label, sizeof(escaped_label));
283 
284 		if (available && active) {
285 			count += sysfs_emit_at(buf, count, "[%s] ", escaped_label);
286 			match = true;
287 		} else if (available) {
288 			count += sysfs_emit_at(buf, count, "%s ", escaped_label);
289 		}
290 	}
291 
292 	if (!match) {
293 		dev_warn(dev, "driver reporting unavailable enum value %d\n", value);
294 		return -EINVAL;
295 	}
296 
297 	if (count)
298 		buf[count - 1] = '\n';
299 
300 	return count;
301 }
302 
power_supply_show_charge_behaviour(struct device * dev,struct power_supply * psy,union power_supply_propval * value,char * buf)303 static ssize_t power_supply_show_charge_behaviour(struct device *dev,
304 						  struct power_supply *psy,
305 						  union power_supply_propval *value,
306 						  char *buf)
307 {
308 	struct power_supply_ext_registration *reg;
309 
310 	scoped_guard(rwsem_read, &psy->extensions_sem) {
311 		power_supply_for_each_extension(reg, psy) {
312 			if (power_supply_ext_has_property(reg->ext,
313 							  POWER_SUPPLY_PROP_CHARGE_BEHAVIOUR))
314 				return power_supply_charge_behaviour_show(dev,
315 						reg->ext->charge_behaviours,
316 						value->intval, buf);
317 		}
318 	}
319 
320 	return power_supply_charge_behaviour_show(dev, psy->desc->charge_behaviours,
321 						  value->intval, buf);
322 }
323 
power_supply_format_property(struct device * dev,bool uevent,struct device_attribute * attr,char * buf)324 static ssize_t power_supply_format_property(struct device *dev,
325 					    bool uevent,
326 					    struct device_attribute *attr,
327 					    char *buf)
328 {
329 	ssize_t ret;
330 	struct power_supply *psy = dev_to_psy(dev);
331 	const struct power_supply_attr *ps_attr = to_ps_attr(attr);
332 	enum power_supply_property psp = dev_attr_psp(attr);
333 	union power_supply_propval value;
334 
335 	if (psp == POWER_SUPPLY_PROP_TYPE) {
336 		value.intval = psy->desc->type;
337 	} else {
338 		ret = power_supply_get_property(psy, psp, &value);
339 
340 		if (ret < 0) {
341 			if (ret == -ENODATA)
342 				dev_dbg_ratelimited(dev,
343 					"driver has no data for `%s' property\n",
344 					attr->attr.name);
345 			else if (ret != -ENODEV && ret != -EAGAIN && ret != -EINVAL)
346 				dev_err_ratelimited(dev,
347 					"driver failed to report `%s' property: %zd\n",
348 					attr->attr.name, ret);
349 			return ret;
350 		}
351 	}
352 
353 	switch (psp) {
354 	case POWER_SUPPLY_PROP_USB_TYPE:
355 		ret = power_supply_show_enum_with_available(
356 				dev, POWER_SUPPLY_USB_TYPE_TEXT,
357 				ARRAY_SIZE(POWER_SUPPLY_USB_TYPE_TEXT),
358 				psy->desc->usb_types, value.intval, buf);
359 		break;
360 	case POWER_SUPPLY_PROP_CHARGE_BEHAVIOUR:
361 		if (uevent) /* no possible values in uevents */
362 			goto default_format;
363 		ret = power_supply_show_charge_behaviour(dev, psy, &value, buf);
364 		break;
365 	case POWER_SUPPLY_PROP_CHARGE_TYPES:
366 		if (uevent) /* no possible values in uevents */
367 			goto default_format;
368 		ret = power_supply_charge_types_show(dev, psy->desc->charge_types,
369 						     value.intval, buf);
370 		break;
371 	case POWER_SUPPLY_PROP_MODEL_NAME ... POWER_SUPPLY_PROP_SERIAL_NUMBER:
372 		ret = sysfs_emit(buf, "%s\n", value.strval);
373 		break;
374 	default:
375 default_format:
376 		if (ps_attr->text_values_len > 0 &&
377 				value.intval < ps_attr->text_values_len && value.intval >= 0) {
378 			ret = sysfs_emit(buf, "%s\n", ps_attr->text_values[value.intval]);
379 		} else {
380 			ret = sysfs_emit(buf, "%d\n", value.intval);
381 		}
382 	}
383 
384 	return ret;
385 }
386 
power_supply_show_property(struct device * dev,struct device_attribute * attr,char * buf)387 static ssize_t power_supply_show_property(struct device *dev,
388 					  struct device_attribute *attr,
389 					  char *buf)
390 {
391 	return power_supply_format_property(dev, false, attr, buf);
392 }
393 
power_supply_store_property(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)394 static ssize_t power_supply_store_property(struct device *dev,
395 					   struct device_attribute *attr,
396 					   const char *buf, size_t count) {
397 	ssize_t ret;
398 	struct power_supply *psy = dev_to_psy(dev);
399 	const struct power_supply_attr *ps_attr = to_ps_attr(attr);
400 	enum power_supply_property psp = dev_attr_psp(attr);
401 	union power_supply_propval value;
402 
403 	ret = -EINVAL;
404 	if (ps_attr->text_values_len > 0) {
405 		ret = power_supply_match_string(ps_attr->text_values,
406 						ps_attr->text_values_len, buf);
407 	}
408 
409 	/*
410 	 * If no match was found, then check to see if it is an integer.
411 	 * Integer values are valid for enums in addition to the text value.
412 	 */
413 	if (ret < 0) {
414 		long long_val;
415 
416 		ret = kstrtol(buf, 10, &long_val);
417 		if (ret < 0)
418 			return ret;
419 
420 		ret = long_val;
421 	}
422 
423 	value.intval = ret;
424 
425 	ret = power_supply_set_property(psy, psp, &value);
426 	if (ret < 0)
427 		return ret;
428 
429 	return count;
430 }
431 
power_supply_attr_is_visible(struct kobject * kobj,struct attribute * attr,int attrno)432 static umode_t power_supply_attr_is_visible(struct kobject *kobj,
433 					   struct attribute *attr,
434 					   int attrno)
435 {
436 	struct device *dev = kobj_to_dev(kobj);
437 	struct power_supply *psy = dev_to_psy(dev);
438 	umode_t mode = S_IRUSR | S_IRGRP | S_IROTH;
439 
440 	if (!power_supply_attrs[attrno].prop_name)
441 		return 0;
442 
443 	if (attrno == POWER_SUPPLY_PROP_TYPE)
444 		return mode;
445 
446 	guard(rwsem_read)(&psy->extensions_sem);
447 
448 	if (power_supply_has_property(psy, attrno)) {
449 		if (power_supply_property_is_writeable(psy, attrno) > 0)
450 			mode |= S_IWUSR;
451 		return mode;
452 	}
453 
454 	return 0;
455 }
456 
457 static const struct attribute_group power_supply_attr_group = {
458 	.attrs = __power_supply_attrs,
459 	.is_visible = power_supply_attr_is_visible,
460 };
461 
462 static struct attribute *power_supply_extension_attrs[] = {
463 	NULL
464 };
465 
466 static const struct attribute_group power_supply_extension_group = {
467 	.name = "extensions",
468 	.attrs = power_supply_extension_attrs,
469 };
470 
471 const struct attribute_group *power_supply_attr_groups[] = {
472 	&power_supply_attr_group,
473 	&power_supply_extension_group,
474 	NULL
475 };
476 
power_supply_init_attrs(void)477 void __init power_supply_init_attrs(void)
478 {
479 	int i;
480 
481 	for (i = 0; i < ARRAY_SIZE(power_supply_attrs); i++) {
482 		struct device_attribute *attr;
483 
484 		if (!power_supply_attrs[i].prop_name) {
485 			pr_warn("%s: Property %d skipped because it is missing from power_supply_attrs\n",
486 				__func__, i);
487 			sprintf(power_supply_attrs[i].attr_name, "_err_%d", i);
488 		} else {
489 			string_lower(power_supply_attrs[i].attr_name,
490 				     power_supply_attrs[i].attr_name);
491 		}
492 
493 		attr = &power_supply_attrs[i].dev_attr;
494 
495 		attr->attr.name = power_supply_attrs[i].attr_name;
496 		attr->show = power_supply_show_property;
497 		attr->store = power_supply_store_property;
498 		__power_supply_attrs[i] = &attr->attr;
499 	}
500 }
501 
add_prop_uevent(const struct device * dev,struct kobj_uevent_env * env,enum power_supply_property prop,char * prop_buf)502 static int add_prop_uevent(const struct device *dev, struct kobj_uevent_env *env,
503 			   enum power_supply_property prop, char *prop_buf)
504 {
505 	int ret = 0;
506 	struct power_supply_attr *pwr_attr;
507 	struct device_attribute *dev_attr;
508 	char *line;
509 
510 	pwr_attr = &power_supply_attrs[prop];
511 	dev_attr = &pwr_attr->dev_attr;
512 
513 	ret = power_supply_format_property((struct device *)dev, true, dev_attr, prop_buf);
514 	if (ret == -ENODEV || ret == -ENODATA || ret == -EINVAL) {
515 		/*
516 		 * When a battery is absent, we expect -ENODEV. Don't abort;
517 		 * send the uevent with at least the PRESENT=0 property
518 		 */
519 		return 0;
520 	}
521 
522 	if (ret < 0)
523 		return ret;
524 
525 	line = strchr(prop_buf, '\n');
526 	if (line)
527 		*line = 0;
528 
529 	return add_uevent_var(env, "POWER_SUPPLY_%s=%s",
530 			      pwr_attr->prop_name, prop_buf);
531 }
532 
power_supply_uevent(const struct device * dev,struct kobj_uevent_env * env)533 int power_supply_uevent(const struct device *dev, struct kobj_uevent_env *env)
534 {
535 	const struct power_supply *psy = dev_to_psy(dev);
536 	int ret = 0, j;
537 	char *prop_buf;
538 
539 	if (!psy || !psy->desc) {
540 		dev_dbg(dev, "No power supply yet\n");
541 		return ret;
542 	}
543 
544 	ret = add_uevent_var(env, "POWER_SUPPLY_NAME=%s", psy->desc->name);
545 	if (ret)
546 		return ret;
547 
548 	/*
549 	 * Kernel generates KOBJ_REMOVE uevent in device removal path, after
550 	 * resources have been freed. Exit early to avoid use-after-free.
551 	 */
552 	if (psy->removing)
553 		return 0;
554 
555 	prop_buf = (char *)get_zeroed_page(GFP_KERNEL);
556 	if (!prop_buf)
557 		return -ENOMEM;
558 
559 	ret = add_prop_uevent(dev, env, POWER_SUPPLY_PROP_TYPE, prop_buf);
560 	if (ret)
561 		goto out;
562 
563 	for (j = 0; j < POWER_SUPPLY_ATTR_CNT; j++) {
564 		ret = add_prop_uevent(dev, env, j, prop_buf);
565 		if (ret)
566 			goto out;
567 	}
568 
569 out:
570 	free_page((unsigned long)prop_buf);
571 
572 	return ret;
573 }
574 
power_supply_charge_behaviour_show(struct device * dev,unsigned int available_behaviours,enum power_supply_charge_behaviour current_behaviour,char * buf)575 ssize_t power_supply_charge_behaviour_show(struct device *dev,
576 					   unsigned int available_behaviours,
577 					   enum power_supply_charge_behaviour current_behaviour,
578 					   char *buf)
579 {
580 	return power_supply_show_enum_with_available(
581 				dev, POWER_SUPPLY_CHARGE_BEHAVIOUR_TEXT,
582 				ARRAY_SIZE(POWER_SUPPLY_CHARGE_BEHAVIOUR_TEXT),
583 				available_behaviours, current_behaviour, buf);
584 }
585 EXPORT_SYMBOL_GPL(power_supply_charge_behaviour_show);
586 
power_supply_charge_behaviour_parse(unsigned int available_behaviours,const char * buf)587 int power_supply_charge_behaviour_parse(unsigned int available_behaviours, const char *buf)
588 {
589 	int i = sysfs_match_string(POWER_SUPPLY_CHARGE_BEHAVIOUR_TEXT, buf);
590 
591 	if (i < 0)
592 		return i;
593 
594 	if (available_behaviours & BIT(i))
595 		return i;
596 
597 	return -EINVAL;
598 }
599 EXPORT_SYMBOL_GPL(power_supply_charge_behaviour_parse);
600 
power_supply_charge_types_show(struct device * dev,unsigned int available_types,enum power_supply_charge_type current_type,char * buf)601 ssize_t power_supply_charge_types_show(struct device *dev,
602 				       unsigned int available_types,
603 				       enum power_supply_charge_type current_type,
604 				       char *buf)
605 {
606 	return power_supply_show_enum_with_available(
607 				dev, POWER_SUPPLY_CHARGE_TYPE_TEXT,
608 				ARRAY_SIZE(POWER_SUPPLY_CHARGE_TYPE_TEXT),
609 				available_types, current_type, buf);
610 }
611 EXPORT_SYMBOL_GPL(power_supply_charge_types_show);
612 
power_supply_charge_types_parse(unsigned int available_types,const char * buf)613 int power_supply_charge_types_parse(unsigned int available_types, const char *buf)
614 {
615 	int i = power_supply_match_string(POWER_SUPPLY_CHARGE_TYPE_TEXT,
616 					  ARRAY_SIZE(POWER_SUPPLY_CHARGE_TYPE_TEXT),
617 					  buf);
618 
619 	if (i < 0)
620 		return i;
621 
622 	if (available_types & BIT(i))
623 		return i;
624 
625 	return -EINVAL;
626 }
627 EXPORT_SYMBOL_GPL(power_supply_charge_types_parse);
628 
power_supply_sysfs_add_extension(struct power_supply * psy,const struct power_supply_ext * ext,struct device * dev)629 int power_supply_sysfs_add_extension(struct power_supply *psy, const struct power_supply_ext *ext,
630 				     struct device *dev)
631 {
632 	return sysfs_add_link_to_group(&psy->dev.kobj, power_supply_extension_group.name,
633 				       &dev->kobj, ext->name);
634 }
635 
power_supply_sysfs_remove_extension(struct power_supply * psy,const struct power_supply_ext * ext)636 void power_supply_sysfs_remove_extension(struct power_supply *psy,
637 					 const struct power_supply_ext *ext)
638 {
639 	sysfs_remove_link_from_group(&psy->dev.kobj, power_supply_extension_group.name, ext->name);
640 }
641