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 
19 #include "power_supply.h"
20 
21 /*
22  * This is because the name "current" breaks the device attr macro.
23  * The "current" word resolves to "(get_current())" so instead of
24  * "current" "(get_current())" appears in the sysfs.
25  *
26  * The source of this definition is the device.h which calls __ATTR
27  * macro in sysfs.h which calls the __stringify macro.
28  *
29  * Only modification that the name is not tried to be resolved
30  * (as a macro let's say).
31  */
32 
33 #define POWER_SUPPLY_ATTR(_name)					\
34 {									\
35 	.attr = { .name = #_name },					\
36 	.show = power_supply_show_property,				\
37 	.store = power_supply_store_property,				\
38 }
39 
40 static struct device_attribute power_supply_attrs[];
41 
42 static const char * const power_supply_type_text[] = {
43 	"Unknown", "Battery", "UPS", "Mains", "USB",
44 	"USB_DCP", "USB_CDP", "USB_ACA", "USB_C",
45 	"USB_PD", "USB_PD_DRP", "BrickID"
46 };
47 
48 static const char * const power_supply_usb_type_text[] = {
49 	"Unknown", "SDP", "DCP", "CDP", "ACA", "C",
50 	"PD", "PD_DRP", "PD_PPS", "BrickID"
51 };
52 
53 static const char * const power_supply_status_text[] = {
54 	"Unknown", "Charging", "Discharging", "Not charging", "Full"
55 };
56 
57 static const char * const power_supply_charge_type_text[] = {
58 	"Unknown", "N/A", "Trickle", "Fast", "Standard", "Adaptive", "Custom"
59 };
60 
61 static const char * const power_supply_health_text[] = {
62 	"Unknown", "Good", "Overheat", "Dead", "Over voltage",
63 	"Unspecified failure", "Cold", "Watchdog timer expire",
64 	"Safety timer expire", "Over current"
65 };
66 
67 static const char * const power_supply_technology_text[] = {
68 	"Unknown", "NiMH", "Li-ion", "Li-poly", "LiFe", "NiCd",
69 	"LiMn"
70 };
71 
72 static const char * const power_supply_capacity_level_text[] = {
73 	"Unknown", "Critical", "Low", "Normal", "High", "Full"
74 };
75 
76 static const char * const power_supply_scope_text[] = {
77 	"Unknown", "System", "Device"
78 };
79 
80 static ssize_t power_supply_show_usb_type(struct device *dev,
81 					  enum power_supply_usb_type *usb_types,
82 					  ssize_t num_usb_types,
83 					  union power_supply_propval *value,
84 					  char *buf)
85 {
86 	enum power_supply_usb_type usb_type;
87 	ssize_t count = 0;
88 	bool match = false;
89 	int i;
90 
91 	for (i = 0; i < num_usb_types; ++i) {
92 		usb_type = usb_types[i];
93 
94 		if (value->intval == usb_type) {
95 			count += sprintf(buf + count, "[%s] ",
96 					 power_supply_usb_type_text[usb_type]);
97 			match = true;
98 		} else {
99 			count += sprintf(buf + count, "%s ",
100 					 power_supply_usb_type_text[usb_type]);
101 		}
102 	}
103 
104 	if (!match) {
105 		dev_warn(dev, "driver reporting unsupported connected type\n");
106 		return -EINVAL;
107 	}
108 
109 	if (count)
110 		buf[count - 1] = '\n';
111 
112 	return count;
113 }
114 
115 static ssize_t power_supply_show_property(struct device *dev,
116 					  struct device_attribute *attr,
117 					  char *buf) {
118 	ssize_t ret;
119 	struct power_supply *psy = dev_get_drvdata(dev);
120 	enum power_supply_property psp = attr - power_supply_attrs;
121 	union power_supply_propval value;
122 
123 	if (psp == POWER_SUPPLY_PROP_TYPE) {
124 		value.intval = psy->desc->type;
125 	} else {
126 		ret = power_supply_get_property(psy, psp, &value);
127 
128 		if (ret < 0) {
129 			if (ret == -ENODATA)
130 				dev_dbg(dev, "driver has no data for `%s' property\n",
131 					attr->attr.name);
132 			else if (ret != -ENODEV && ret != -EAGAIN)
133 				dev_err_ratelimited(dev,
134 					"driver failed to report `%s' property: %zd\n",
135 					attr->attr.name, ret);
136 			return ret;
137 		}
138 	}
139 
140 	switch (psp) {
141 	case POWER_SUPPLY_PROP_STATUS:
142 		ret = sprintf(buf, "%s\n",
143 			      power_supply_status_text[value.intval]);
144 		break;
145 	case POWER_SUPPLY_PROP_CHARGE_TYPE:
146 		ret = sprintf(buf, "%s\n",
147 			      power_supply_charge_type_text[value.intval]);
148 		break;
149 	case POWER_SUPPLY_PROP_HEALTH:
150 		ret = sprintf(buf, "%s\n",
151 			      power_supply_health_text[value.intval]);
152 		break;
153 	case POWER_SUPPLY_PROP_TECHNOLOGY:
154 		ret = sprintf(buf, "%s\n",
155 			      power_supply_technology_text[value.intval]);
156 		break;
157 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
158 		ret = sprintf(buf, "%s\n",
159 			      power_supply_capacity_level_text[value.intval]);
160 		break;
161 	case POWER_SUPPLY_PROP_TYPE:
162 		ret = sprintf(buf, "%s\n",
163 			      power_supply_type_text[value.intval]);
164 		break;
165 	case POWER_SUPPLY_PROP_USB_TYPE:
166 		ret = power_supply_show_usb_type(dev, psy->desc->usb_types,
167 						 psy->desc->num_usb_types,
168 						 &value, buf);
169 		break;
170 	case POWER_SUPPLY_PROP_SCOPE:
171 		ret = sprintf(buf, "%s\n",
172 			      power_supply_scope_text[value.intval]);
173 		break;
174 	case POWER_SUPPLY_PROP_MODEL_NAME ... POWER_SUPPLY_PROP_SERIAL_NUMBER:
175 		ret = sprintf(buf, "%s\n", value.strval);
176 		break;
177 	default:
178 		ret = sprintf(buf, "%d\n", value.intval);
179 	}
180 
181 	return ret;
182 }
183 
184 static ssize_t power_supply_store_property(struct device *dev,
185 					   struct device_attribute *attr,
186 					   const char *buf, size_t count) {
187 	ssize_t ret;
188 	struct power_supply *psy = dev_get_drvdata(dev);
189 	enum power_supply_property psp = attr - power_supply_attrs;
190 	union power_supply_propval value;
191 
192 	switch (psp) {
193 	case POWER_SUPPLY_PROP_STATUS:
194 		ret = sysfs_match_string(power_supply_status_text, buf);
195 		break;
196 	case POWER_SUPPLY_PROP_CHARGE_TYPE:
197 		ret = sysfs_match_string(power_supply_charge_type_text, buf);
198 		break;
199 	case POWER_SUPPLY_PROP_HEALTH:
200 		ret = sysfs_match_string(power_supply_health_text, buf);
201 		break;
202 	case POWER_SUPPLY_PROP_TECHNOLOGY:
203 		ret = sysfs_match_string(power_supply_technology_text, buf);
204 		break;
205 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
206 		ret = sysfs_match_string(power_supply_capacity_level_text, buf);
207 		break;
208 	case POWER_SUPPLY_PROP_SCOPE:
209 		ret = sysfs_match_string(power_supply_scope_text, buf);
210 		break;
211 	default:
212 		ret = -EINVAL;
213 	}
214 
215 	/*
216 	 * If no match was found, then check to see if it is an integer.
217 	 * Integer values are valid for enums in addition to the text value.
218 	 */
219 	if (ret < 0) {
220 		long long_val;
221 
222 		ret = kstrtol(buf, 10, &long_val);
223 		if (ret < 0)
224 			return ret;
225 
226 		ret = long_val;
227 	}
228 
229 	value.intval = ret;
230 
231 	ret = power_supply_set_property(psy, psp, &value);
232 	if (ret < 0)
233 		return ret;
234 
235 	return count;
236 }
237 
238 /* Must be in the same order as POWER_SUPPLY_PROP_* */
239 static struct device_attribute power_supply_attrs[] = {
240 	/* Properties of type `int' */
241 	POWER_SUPPLY_ATTR(status),
242 	POWER_SUPPLY_ATTR(charge_type),
243 	POWER_SUPPLY_ATTR(health),
244 	POWER_SUPPLY_ATTR(present),
245 	POWER_SUPPLY_ATTR(online),
246 	POWER_SUPPLY_ATTR(authentic),
247 	POWER_SUPPLY_ATTR(technology),
248 	POWER_SUPPLY_ATTR(cycle_count),
249 	POWER_SUPPLY_ATTR(voltage_max),
250 	POWER_SUPPLY_ATTR(voltage_min),
251 	POWER_SUPPLY_ATTR(voltage_max_design),
252 	POWER_SUPPLY_ATTR(voltage_min_design),
253 	POWER_SUPPLY_ATTR(voltage_now),
254 	POWER_SUPPLY_ATTR(voltage_avg),
255 	POWER_SUPPLY_ATTR(voltage_ocv),
256 	POWER_SUPPLY_ATTR(voltage_boot),
257 	POWER_SUPPLY_ATTR(current_max),
258 	POWER_SUPPLY_ATTR(current_now),
259 	POWER_SUPPLY_ATTR(current_avg),
260 	POWER_SUPPLY_ATTR(current_boot),
261 	POWER_SUPPLY_ATTR(power_now),
262 	POWER_SUPPLY_ATTR(power_avg),
263 	POWER_SUPPLY_ATTR(charge_full_design),
264 	POWER_SUPPLY_ATTR(charge_empty_design),
265 	POWER_SUPPLY_ATTR(charge_full),
266 	POWER_SUPPLY_ATTR(charge_empty),
267 	POWER_SUPPLY_ATTR(charge_now),
268 	POWER_SUPPLY_ATTR(charge_avg),
269 	POWER_SUPPLY_ATTR(charge_counter),
270 	POWER_SUPPLY_ATTR(constant_charge_current),
271 	POWER_SUPPLY_ATTR(constant_charge_current_max),
272 	POWER_SUPPLY_ATTR(constant_charge_voltage),
273 	POWER_SUPPLY_ATTR(constant_charge_voltage_max),
274 	POWER_SUPPLY_ATTR(charge_control_limit),
275 	POWER_SUPPLY_ATTR(charge_control_limit_max),
276 	POWER_SUPPLY_ATTR(charge_control_start_threshold),
277 	POWER_SUPPLY_ATTR(charge_control_end_threshold),
278 	POWER_SUPPLY_ATTR(input_current_limit),
279 	POWER_SUPPLY_ATTR(energy_full_design),
280 	POWER_SUPPLY_ATTR(energy_empty_design),
281 	POWER_SUPPLY_ATTR(energy_full),
282 	POWER_SUPPLY_ATTR(energy_empty),
283 	POWER_SUPPLY_ATTR(energy_now),
284 	POWER_SUPPLY_ATTR(energy_avg),
285 	POWER_SUPPLY_ATTR(capacity),
286 	POWER_SUPPLY_ATTR(capacity_alert_min),
287 	POWER_SUPPLY_ATTR(capacity_alert_max),
288 	POWER_SUPPLY_ATTR(capacity_level),
289 	POWER_SUPPLY_ATTR(temp),
290 	POWER_SUPPLY_ATTR(temp_max),
291 	POWER_SUPPLY_ATTR(temp_min),
292 	POWER_SUPPLY_ATTR(temp_alert_min),
293 	POWER_SUPPLY_ATTR(temp_alert_max),
294 	POWER_SUPPLY_ATTR(temp_ambient),
295 	POWER_SUPPLY_ATTR(temp_ambient_alert_min),
296 	POWER_SUPPLY_ATTR(temp_ambient_alert_max),
297 	POWER_SUPPLY_ATTR(time_to_empty_now),
298 	POWER_SUPPLY_ATTR(time_to_empty_avg),
299 	POWER_SUPPLY_ATTR(time_to_full_now),
300 	POWER_SUPPLY_ATTR(time_to_full_avg),
301 	POWER_SUPPLY_ATTR(type),
302 	POWER_SUPPLY_ATTR(usb_type),
303 	POWER_SUPPLY_ATTR(scope),
304 	POWER_SUPPLY_ATTR(precharge_current),
305 	POWER_SUPPLY_ATTR(charge_term_current),
306 	POWER_SUPPLY_ATTR(calibrate),
307 	/* Properties of type `const char *' */
308 	POWER_SUPPLY_ATTR(model_name),
309 	POWER_SUPPLY_ATTR(manufacturer),
310 	POWER_SUPPLY_ATTR(serial_number),
311 };
312 
313 static struct attribute *
314 __power_supply_attrs[ARRAY_SIZE(power_supply_attrs) + 1];
315 
316 static umode_t power_supply_attr_is_visible(struct kobject *kobj,
317 					   struct attribute *attr,
318 					   int attrno)
319 {
320 	struct device *dev = container_of(kobj, struct device, kobj);
321 	struct power_supply *psy = dev_get_drvdata(dev);
322 	umode_t mode = S_IRUSR | S_IRGRP | S_IROTH;
323 	int i;
324 
325 	if (attrno == POWER_SUPPLY_PROP_TYPE)
326 		return mode;
327 
328 	for (i = 0; i < psy->desc->num_properties; i++) {
329 		int property = psy->desc->properties[i];
330 
331 		if (property == attrno) {
332 			if (psy->desc->property_is_writeable &&
333 			    psy->desc->property_is_writeable(psy, property) > 0)
334 				mode |= S_IWUSR;
335 
336 			return mode;
337 		}
338 	}
339 
340 	return 0;
341 }
342 
343 static struct attribute_group power_supply_attr_group = {
344 	.attrs = __power_supply_attrs,
345 	.is_visible = power_supply_attr_is_visible,
346 };
347 
348 static const struct attribute_group *power_supply_attr_groups[] = {
349 	&power_supply_attr_group,
350 	NULL,
351 };
352 
353 void power_supply_init_attrs(struct device_type *dev_type)
354 {
355 	int i;
356 
357 	dev_type->groups = power_supply_attr_groups;
358 
359 	for (i = 0; i < ARRAY_SIZE(power_supply_attrs); i++)
360 		__power_supply_attrs[i] = &power_supply_attrs[i].attr;
361 }
362 
363 static char *kstruprdup(const char *str, gfp_t gfp)
364 {
365 	char *ret, *ustr;
366 
367 	ustr = ret = kmalloc(strlen(str) + 1, gfp);
368 
369 	if (!ret)
370 		return NULL;
371 
372 	while (*str)
373 		*ustr++ = toupper(*str++);
374 
375 	*ustr = 0;
376 
377 	return ret;
378 }
379 
380 int power_supply_uevent(struct device *dev, struct kobj_uevent_env *env)
381 {
382 	struct power_supply *psy = dev_get_drvdata(dev);
383 	int ret = 0, j;
384 	char *prop_buf;
385 	char *attrname;
386 
387 	if (!psy || !psy->desc) {
388 		dev_dbg(dev, "No power supply yet\n");
389 		return ret;
390 	}
391 
392 	ret = add_uevent_var(env, "POWER_SUPPLY_NAME=%s", psy->desc->name);
393 	if (ret)
394 		return ret;
395 
396 	prop_buf = (char *)get_zeroed_page(GFP_KERNEL);
397 	if (!prop_buf)
398 		return -ENOMEM;
399 
400 	for (j = 0; j < psy->desc->num_properties; j++) {
401 		struct device_attribute *attr;
402 		char *line;
403 
404 		attr = &power_supply_attrs[psy->desc->properties[j]];
405 
406 		ret = power_supply_show_property(dev, attr, prop_buf);
407 		if (ret == -ENODEV || ret == -ENODATA) {
408 			/* When a battery is absent, we expect -ENODEV. Don't abort;
409 			   send the uevent with at least the the PRESENT=0 property */
410 			ret = 0;
411 			continue;
412 		}
413 
414 		if (ret < 0)
415 			goto out;
416 
417 		line = strchr(prop_buf, '\n');
418 		if (line)
419 			*line = 0;
420 
421 		attrname = kstruprdup(attr->attr.name, GFP_KERNEL);
422 		if (!attrname) {
423 			ret = -ENOMEM;
424 			goto out;
425 		}
426 
427 		ret = add_uevent_var(env, "POWER_SUPPLY_%s=%s", attrname, prop_buf);
428 		kfree(attrname);
429 		if (ret)
430 			goto out;
431 	}
432 
433 out:
434 	free_page((unsigned long)prop_buf);
435 
436 	return ret;
437 }
438