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 <dwmw2@infradead.org>
6 * Copyright © 2007 Anton Vorontsov <cbou@mail.ru>
7 * Copyright © 2004 Szabolcs Gyurko
8 * Copyright © 2003 Ian Molton <spyro@f2s.com>
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
24struct 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
47static 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
63static 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
76static 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
84static 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
96static 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_UNSPEC_FAILURE] = "Unspecified failure",
103 [POWER_SUPPLY_HEALTH_COLD] = "Cold",
104 [POWER_SUPPLY_HEALTH_WATCHDOG_TIMER_EXPIRE] = "Watchdog timer expire",
105 [POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE] = "Safety timer expire",
106 [POWER_SUPPLY_HEALTH_OVERCURRENT] = "Over current",
107 [POWER_SUPPLY_HEALTH_CALIBRATION_REQUIRED] = "Calibration required",
108 [POWER_SUPPLY_HEALTH_WARM] = "Warm",
109 [POWER_SUPPLY_HEALTH_COOL] = "Cool",
110 [POWER_SUPPLY_HEALTH_HOT] = "Hot",
111 [POWER_SUPPLY_HEALTH_NO_BATTERY] = "No battery",
112};
113
114static const char * const POWER_SUPPLY_TECHNOLOGY_TEXT[] = {
115 [POWER_SUPPLY_TECHNOLOGY_UNKNOWN] = "Unknown",
116 [POWER_SUPPLY_TECHNOLOGY_NiMH] = "NiMH",
117 [POWER_SUPPLY_TECHNOLOGY_LION] = "Li-ion",
118 [POWER_SUPPLY_TECHNOLOGY_LIPO] = "Li-poly",
119 [POWER_SUPPLY_TECHNOLOGY_LiFe] = "LiFe",
120 [POWER_SUPPLY_TECHNOLOGY_NiCd] = "NiCd",
121 [POWER_SUPPLY_TECHNOLOGY_LiMn] = "LiMn",
122};
123
124static const char * const POWER_SUPPLY_CAPACITY_LEVEL_TEXT[] = {
125 [POWER_SUPPLY_CAPACITY_LEVEL_UNKNOWN] = "Unknown",
126 [POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL] = "Critical",
127 [POWER_SUPPLY_CAPACITY_LEVEL_LOW] = "Low",
128 [POWER_SUPPLY_CAPACITY_LEVEL_NORMAL] = "Normal",
129 [POWER_SUPPLY_CAPACITY_LEVEL_HIGH] = "High",
130 [POWER_SUPPLY_CAPACITY_LEVEL_FULL] = "Full",
131};
132
133static const char * const POWER_SUPPLY_SCOPE_TEXT[] = {
134 [POWER_SUPPLY_SCOPE_UNKNOWN] = "Unknown",
135 [POWER_SUPPLY_SCOPE_SYSTEM] = "System",
136 [POWER_SUPPLY_SCOPE_DEVICE] = "Device",
137};
138
139static const char * const POWER_SUPPLY_CHARGE_BEHAVIOUR_TEXT[] = {
140 [POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO] = "auto",
141 [POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE] = "inhibit-charge",
142 [POWER_SUPPLY_CHARGE_BEHAVIOUR_FORCE_DISCHARGE] = "force-discharge",
143};
144
145static struct power_supply_attr power_supply_attrs[] = {
146 /* Properties of type `int' */
147 POWER_SUPPLY_ENUM_ATTR(STATUS),
148 POWER_SUPPLY_ENUM_ATTR(CHARGE_TYPE),
149 POWER_SUPPLY_ENUM_ATTR(HEALTH),
150 POWER_SUPPLY_ATTR(PRESENT),
151 POWER_SUPPLY_ATTR(ONLINE),
152 POWER_SUPPLY_ATTR(AUTHENTIC),
153 POWER_SUPPLY_ENUM_ATTR(TECHNOLOGY),
154 POWER_SUPPLY_ATTR(CYCLE_COUNT),
155 POWER_SUPPLY_ATTR(VOLTAGE_MAX),
156 POWER_SUPPLY_ATTR(VOLTAGE_MIN),
157 POWER_SUPPLY_ATTR(VOLTAGE_MAX_DESIGN),
158 POWER_SUPPLY_ATTR(VOLTAGE_MIN_DESIGN),
159 POWER_SUPPLY_ATTR(VOLTAGE_NOW),
160 POWER_SUPPLY_ATTR(VOLTAGE_AVG),
161 POWER_SUPPLY_ATTR(VOLTAGE_OCV),
162 POWER_SUPPLY_ATTR(VOLTAGE_BOOT),
163 POWER_SUPPLY_ATTR(CURRENT_MAX),
164 POWER_SUPPLY_ATTR(CURRENT_NOW),
165 POWER_SUPPLY_ATTR(CURRENT_AVG),
166 POWER_SUPPLY_ATTR(CURRENT_BOOT),
167 POWER_SUPPLY_ATTR(POWER_NOW),
168 POWER_SUPPLY_ATTR(POWER_AVG),
169 POWER_SUPPLY_ATTR(CHARGE_FULL_DESIGN),
170 POWER_SUPPLY_ATTR(CHARGE_EMPTY_DESIGN),
171 POWER_SUPPLY_ATTR(CHARGE_FULL),
172 POWER_SUPPLY_ATTR(CHARGE_EMPTY),
173 POWER_SUPPLY_ATTR(CHARGE_NOW),
174 POWER_SUPPLY_ATTR(CHARGE_AVG),
175 POWER_SUPPLY_ATTR(CHARGE_COUNTER),
176 POWER_SUPPLY_ATTR(CONSTANT_CHARGE_CURRENT),
177 POWER_SUPPLY_ATTR(CONSTANT_CHARGE_CURRENT_MAX),
178 POWER_SUPPLY_ATTR(CONSTANT_CHARGE_VOLTAGE),
179 POWER_SUPPLY_ATTR(CONSTANT_CHARGE_VOLTAGE_MAX),
180 POWER_SUPPLY_ATTR(CHARGE_CONTROL_LIMIT),
181 POWER_SUPPLY_ATTR(CHARGE_CONTROL_LIMIT_MAX),
182 POWER_SUPPLY_ATTR(CHARGE_CONTROL_START_THRESHOLD),
183 POWER_SUPPLY_ATTR(CHARGE_CONTROL_END_THRESHOLD),
184 POWER_SUPPLY_ENUM_ATTR(CHARGE_BEHAVIOUR),
185 POWER_SUPPLY_ATTR(INPUT_CURRENT_LIMIT),
186 POWER_SUPPLY_ATTR(INPUT_VOLTAGE_LIMIT),
187 POWER_SUPPLY_ATTR(INPUT_POWER_LIMIT),
188 POWER_SUPPLY_ATTR(ENERGY_FULL_DESIGN),
189 POWER_SUPPLY_ATTR(ENERGY_EMPTY_DESIGN),
190 POWER_SUPPLY_ATTR(ENERGY_FULL),
191 POWER_SUPPLY_ATTR(ENERGY_EMPTY),
192 POWER_SUPPLY_ATTR(ENERGY_NOW),
193 POWER_SUPPLY_ATTR(ENERGY_AVG),
194 POWER_SUPPLY_ATTR(CAPACITY),
195 POWER_SUPPLY_ATTR(CAPACITY_ALERT_MIN),
196 POWER_SUPPLY_ATTR(CAPACITY_ALERT_MAX),
197 POWER_SUPPLY_ATTR(CAPACITY_ERROR_MARGIN),
198 POWER_SUPPLY_ENUM_ATTR(CAPACITY_LEVEL),
199 POWER_SUPPLY_ATTR(TEMP),
200 POWER_SUPPLY_ATTR(TEMP_MAX),
201 POWER_SUPPLY_ATTR(TEMP_MIN),
202 POWER_SUPPLY_ATTR(TEMP_ALERT_MIN),
203 POWER_SUPPLY_ATTR(TEMP_ALERT_MAX),
204 POWER_SUPPLY_ATTR(TEMP_AMBIENT),
205 POWER_SUPPLY_ATTR(TEMP_AMBIENT_ALERT_MIN),
206 POWER_SUPPLY_ATTR(TEMP_AMBIENT_ALERT_MAX),
207 POWER_SUPPLY_ATTR(TIME_TO_EMPTY_NOW),
208 POWER_SUPPLY_ATTR(TIME_TO_EMPTY_AVG),
209 POWER_SUPPLY_ATTR(TIME_TO_FULL_NOW),
210 POWER_SUPPLY_ATTR(TIME_TO_FULL_AVG),
211 POWER_SUPPLY_ENUM_ATTR(TYPE),
212 POWER_SUPPLY_ATTR(USB_TYPE),
213 POWER_SUPPLY_ENUM_ATTR(SCOPE),
214 POWER_SUPPLY_ATTR(PRECHARGE_CURRENT),
215 POWER_SUPPLY_ATTR(CHARGE_TERM_CURRENT),
216 POWER_SUPPLY_ATTR(CALIBRATE),
217 POWER_SUPPLY_ATTR(MANUFACTURE_YEAR),
218 POWER_SUPPLY_ATTR(MANUFACTURE_MONTH),
219 POWER_SUPPLY_ATTR(MANUFACTURE_DAY),
220 /* Properties of type `const char *' */
221 POWER_SUPPLY_ATTR(MODEL_NAME),
222 POWER_SUPPLY_ATTR(MANUFACTURER),
223 POWER_SUPPLY_ATTR(SERIAL_NUMBER),
224};
225#define POWER_SUPPLY_ATTR_CNT ARRAY_SIZE(power_supply_attrs)
226
227static struct attribute *
228__power_supply_attrs[POWER_SUPPLY_ATTR_CNT + 1];
229
230static struct power_supply_attr *to_ps_attr(struct device_attribute *attr)
231{
232 return container_of(attr, struct power_supply_attr, dev_attr);
233}
234
235static enum power_supply_property dev_attr_psp(struct device_attribute *attr)
236{
237 return to_ps_attr(attr) - power_supply_attrs;
238}
239
240static ssize_t power_supply_show_usb_type(struct device *dev,
241 const struct power_supply_desc *desc,
242 union power_supply_propval *value,
243 char *buf)
244{
245 enum power_supply_usb_type usb_type;
246 ssize_t count = 0;
247 bool match = false;
248 int i;
249
250 for (i = 0; i < desc->num_usb_types; ++i) {
251 usb_type = desc->usb_types[i];
252
253 if (value->intval == usb_type) {
254 count += sysfs_emit_at(buf, at: count, fmt: "[%s] ",
255 POWER_SUPPLY_USB_TYPE_TEXT[usb_type]);
256 match = true;
257 } else {
258 count += sysfs_emit_at(buf, at: count, fmt: "%s ",
259 POWER_SUPPLY_USB_TYPE_TEXT[usb_type]);
260 }
261 }
262
263 if (!match) {
264 dev_warn(dev, "driver reporting unsupported connected type\n");
265 return -EINVAL;
266 }
267
268 if (count)
269 buf[count - 1] = '\n';
270
271 return count;
272}
273
274static ssize_t power_supply_show_property(struct device *dev,
275 struct device_attribute *attr,
276 char *buf) {
277 ssize_t ret;
278 struct power_supply *psy = dev_get_drvdata(dev);
279 struct power_supply_attr *ps_attr = to_ps_attr(attr);
280 enum power_supply_property psp = dev_attr_psp(attr);
281 union power_supply_propval value;
282
283 if (psp == POWER_SUPPLY_PROP_TYPE) {
284 value.intval = psy->desc->type;
285 } else {
286 ret = power_supply_get_property(psy, psp, val: &value);
287
288 if (ret < 0) {
289 if (ret == -ENODATA)
290 dev_dbg_ratelimited(dev,
291 "driver has no data for `%s' property\n",
292 attr->attr.name);
293 else if (ret != -ENODEV && ret != -EAGAIN)
294 dev_err_ratelimited(dev,
295 "driver failed to report `%s' property: %zd\n",
296 attr->attr.name, ret);
297 return ret;
298 }
299 }
300
301 if (ps_attr->text_values_len > 0 &&
302 value.intval < ps_attr->text_values_len && value.intval >= 0) {
303 return sysfs_emit(buf, fmt: "%s\n", ps_attr->text_values[value.intval]);
304 }
305
306 switch (psp) {
307 case POWER_SUPPLY_PROP_USB_TYPE:
308 ret = power_supply_show_usb_type(dev, desc: psy->desc,
309 value: &value, buf);
310 break;
311 case POWER_SUPPLY_PROP_MODEL_NAME ... POWER_SUPPLY_PROP_SERIAL_NUMBER:
312 ret = sysfs_emit(buf, fmt: "%s\n", value.strval);
313 break;
314 default:
315 ret = sysfs_emit(buf, fmt: "%d\n", value.intval);
316 }
317
318 return ret;
319}
320
321static ssize_t power_supply_store_property(struct device *dev,
322 struct device_attribute *attr,
323 const char *buf, size_t count) {
324 ssize_t ret;
325 struct power_supply *psy = dev_get_drvdata(dev);
326 struct power_supply_attr *ps_attr = to_ps_attr(attr);
327 enum power_supply_property psp = dev_attr_psp(attr);
328 union power_supply_propval value;
329
330 ret = -EINVAL;
331 if (ps_attr->text_values_len > 0) {
332 ret = __sysfs_match_string(array: ps_attr->text_values,
333 n: ps_attr->text_values_len, s: buf);
334 }
335
336 /*
337 * If no match was found, then check to see if it is an integer.
338 * Integer values are valid for enums in addition to the text value.
339 */
340 if (ret < 0) {
341 long long_val;
342
343 ret = kstrtol(s: buf, base: 10, res: &long_val);
344 if (ret < 0)
345 return ret;
346
347 ret = long_val;
348 }
349
350 value.intval = ret;
351
352 ret = power_supply_set_property(psy, psp, val: &value);
353 if (ret < 0)
354 return ret;
355
356 return count;
357}
358
359static umode_t power_supply_attr_is_visible(struct kobject *kobj,
360 struct attribute *attr,
361 int attrno)
362{
363 struct device *dev = kobj_to_dev(kobj);
364 struct power_supply *psy = dev_get_drvdata(dev);
365 umode_t mode = S_IRUSR | S_IRGRP | S_IROTH;
366 int i;
367
368 if (!power_supply_attrs[attrno].prop_name)
369 return 0;
370
371 if (attrno == POWER_SUPPLY_PROP_TYPE)
372 return mode;
373
374 for (i = 0; i < psy->desc->num_properties; i++) {
375 int property = psy->desc->properties[i];
376
377 if (property == attrno) {
378 if (psy->desc->property_is_writeable &&
379 psy->desc->property_is_writeable(psy, property) > 0)
380 mode |= S_IWUSR;
381
382 return mode;
383 }
384 }
385
386 if (power_supply_battery_info_has_prop(info: psy->battery_info, psp: attrno))
387 return mode;
388
389 return 0;
390}
391
392static const struct attribute_group power_supply_attr_group = {
393 .attrs = __power_supply_attrs,
394 .is_visible = power_supply_attr_is_visible,
395};
396
397static const struct attribute_group *power_supply_attr_groups[] = {
398 &power_supply_attr_group,
399 NULL,
400};
401
402void power_supply_init_attrs(struct device_type *dev_type)
403{
404 int i;
405
406 dev_type->groups = power_supply_attr_groups;
407
408 for (i = 0; i < ARRAY_SIZE(power_supply_attrs); i++) {
409 struct device_attribute *attr;
410
411 if (!power_supply_attrs[i].prop_name) {
412 pr_warn("%s: Property %d skipped because it is missing from power_supply_attrs\n",
413 __func__, i);
414 sprintf(buf: power_supply_attrs[i].attr_name, fmt: "_err_%d", i);
415 } else {
416 string_lower(dst: power_supply_attrs[i].attr_name,
417 src: power_supply_attrs[i].attr_name);
418 }
419
420 attr = &power_supply_attrs[i].dev_attr;
421
422 attr->attr.name = power_supply_attrs[i].attr_name;
423 attr->show = power_supply_show_property;
424 attr->store = power_supply_store_property;
425 __power_supply_attrs[i] = &attr->attr;
426 }
427}
428
429static int add_prop_uevent(const struct device *dev, struct kobj_uevent_env *env,
430 enum power_supply_property prop, char *prop_buf)
431{
432 int ret = 0;
433 struct power_supply_attr *pwr_attr;
434 struct device_attribute *dev_attr;
435 char *line;
436
437 pwr_attr = &power_supply_attrs[prop];
438 dev_attr = &pwr_attr->dev_attr;
439
440 ret = power_supply_show_property(dev: (struct device *)dev, attr: dev_attr, buf: prop_buf);
441 if (ret == -ENODEV || ret == -ENODATA) {
442 /*
443 * When a battery is absent, we expect -ENODEV. Don't abort;
444 * send the uevent with at least the PRESENT=0 property
445 */
446 return 0;
447 }
448
449 if (ret < 0)
450 return ret;
451
452 line = strchr(prop_buf, '\n');
453 if (line)
454 *line = 0;
455
456 return add_uevent_var(env, format: "POWER_SUPPLY_%s=%s",
457 pwr_attr->prop_name, prop_buf);
458}
459
460int power_supply_uevent(const struct device *dev, struct kobj_uevent_env *env)
461{
462 const struct power_supply *psy = dev_get_drvdata(dev);
463 const enum power_supply_property *battery_props =
464 power_supply_battery_info_properties;
465 unsigned long psy_drv_properties[POWER_SUPPLY_ATTR_CNT /
466 sizeof(unsigned long) + 1] = {0};
467 int ret = 0, j;
468 char *prop_buf;
469
470 if (!psy || !psy->desc) {
471 dev_dbg(dev, "No power supply yet\n");
472 return ret;
473 }
474
475 ret = add_uevent_var(env, format: "POWER_SUPPLY_NAME=%s", psy->desc->name);
476 if (ret)
477 return ret;
478
479 /*
480 * Kernel generates KOBJ_REMOVE uevent in device removal path, after
481 * resources have been freed. Exit early to avoid use-after-free.
482 */
483 if (psy->removing)
484 return 0;
485
486 prop_buf = (char *)get_zeroed_page(GFP_KERNEL);
487 if (!prop_buf)
488 return -ENOMEM;
489
490 ret = add_prop_uevent(dev, env, prop: POWER_SUPPLY_PROP_TYPE, prop_buf);
491 if (ret)
492 goto out;
493
494 for (j = 0; j < psy->desc->num_properties; j++) {
495 set_bit(nr: psy->desc->properties[j], addr: psy_drv_properties);
496 ret = add_prop_uevent(dev, env, prop: psy->desc->properties[j],
497 prop_buf);
498 if (ret)
499 goto out;
500 }
501
502 for (j = 0; j < power_supply_battery_info_properties_size; j++) {
503 if (test_bit(battery_props[j], psy_drv_properties))
504 continue;
505 if (!power_supply_battery_info_has_prop(info: psy->battery_info,
506 psp: battery_props[j]))
507 continue;
508 ret = add_prop_uevent(dev, env, prop: battery_props[j],
509 prop_buf);
510 if (ret)
511 goto out;
512 }
513
514out:
515 free_page((unsigned long)prop_buf);
516
517 return ret;
518}
519
520ssize_t power_supply_charge_behaviour_show(struct device *dev,
521 unsigned int available_behaviours,
522 enum power_supply_charge_behaviour current_behaviour,
523 char *buf)
524{
525 bool match = false, available, active;
526 ssize_t count = 0;
527 int i;
528
529 for (i = 0; i < ARRAY_SIZE(POWER_SUPPLY_CHARGE_BEHAVIOUR_TEXT); i++) {
530 available = available_behaviours & BIT(i);
531 active = i == current_behaviour;
532
533 if (available && active) {
534 count += sysfs_emit_at(buf, at: count, fmt: "[%s] ",
535 POWER_SUPPLY_CHARGE_BEHAVIOUR_TEXT[i]);
536 match = true;
537 } else if (available) {
538 count += sysfs_emit_at(buf, at: count, fmt: "%s ",
539 POWER_SUPPLY_CHARGE_BEHAVIOUR_TEXT[i]);
540 }
541 }
542
543 if (!match) {
544 dev_warn(dev, "driver reporting unsupported charge behaviour\n");
545 return -EINVAL;
546 }
547
548 if (count)
549 buf[count - 1] = '\n';
550
551 return count;
552}
553EXPORT_SYMBOL_GPL(power_supply_charge_behaviour_show);
554
555int power_supply_charge_behaviour_parse(unsigned int available_behaviours, const char *buf)
556{
557 int i = sysfs_match_string(POWER_SUPPLY_CHARGE_BEHAVIOUR_TEXT, buf);
558
559 if (i < 0)
560 return i;
561
562 if (available_behaviours & BIT(i))
563 return i;
564
565 return -EINVAL;
566}
567EXPORT_SYMBOL_GPL(power_supply_charge_behaviour_parse);
568

source code of linux/drivers/power/supply/power_supply_sysfs.c