1 /*
2  *  Sysfs interface for the universal power supply monitor class
3  *
4  *  Copyright © 2007  David Woodhouse <dwmw2@infradead.org>
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  *  You may use this code as per GPL version 2
12  */
13 
14 #include <linux/ctype.h>
15 #include <linux/device.h>
16 #include <linux/power_supply.h>
17 #include <linux/slab.h>
18 #include <linux/stat.h>
19 
20 #include "power_supply.h"
21 
22 /*
23  * This is because the name "current" breaks the device attr macro.
24  * The "current" word resolves to "(get_current())" so instead of
25  * "current" "(get_current())" appears in the sysfs.
26  *
27  * The source of this definition is the device.h which calls __ATTR
28  * macro in sysfs.h which calls the __stringify macro.
29  *
30  * Only modification that the name is not tried to be resolved
31  * (as a macro let's say).
32  */
33 
34 #define POWER_SUPPLY_ATTR(_name)					\
35 {									\
36 	.attr = { .name = #_name },					\
37 	.show = power_supply_show_property,				\
38 	.store = power_supply_store_property,				\
39 }
40 
41 static struct device_attribute power_supply_attrs[];
42 
43 static ssize_t power_supply_show_property(struct device *dev,
44 					  struct device_attribute *attr,
45 					  char *buf) {
46 	static char *type_text[] = {
47 		"Unknown", "Battery", "UPS", "Mains", "USB",
48 		"USB_DCP", "USB_CDP", "USB_ACA", "USB_C",
49 		"USB_PD", "USB_PD_DRP"
50 	};
51 	static char *status_text[] = {
52 		"Unknown", "Charging", "Discharging", "Not charging", "Full"
53 	};
54 	static char *charge_type[] = {
55 		"Unknown", "N/A", "Trickle", "Fast"
56 	};
57 	static char *health_text[] = {
58 		"Unknown", "Good", "Overheat", "Dead", "Over voltage",
59 		"Unspecified failure", "Cold", "Watchdog timer expire",
60 		"Safety timer expire"
61 	};
62 	static char *technology_text[] = {
63 		"Unknown", "NiMH", "Li-ion", "Li-poly", "LiFe", "NiCd",
64 		"LiMn"
65 	};
66 	static char *capacity_level_text[] = {
67 		"Unknown", "Critical", "Low", "Normal", "High", "Full"
68 	};
69 	static char *scope_text[] = {
70 		"Unknown", "System", "Device"
71 	};
72 	ssize_t ret = 0;
73 	struct power_supply *psy = dev_get_drvdata(dev);
74 	const ptrdiff_t off = attr - power_supply_attrs;
75 	union power_supply_propval value;
76 
77 	if (off == POWER_SUPPLY_PROP_TYPE) {
78 		value.intval = psy->desc->type;
79 	} else {
80 		ret = power_supply_get_property(psy, off, &value);
81 
82 		if (ret < 0) {
83 			if (ret == -ENODATA)
84 				dev_dbg(dev, "driver has no data for `%s' property\n",
85 					attr->attr.name);
86 			else if (ret != -ENODEV && ret != -EAGAIN)
87 				dev_err(dev, "driver failed to report `%s' property: %zd\n",
88 					attr->attr.name, ret);
89 			return ret;
90 		}
91 	}
92 
93 	if (off == POWER_SUPPLY_PROP_STATUS)
94 		return sprintf(buf, "%s\n", status_text[value.intval]);
95 	else if (off == POWER_SUPPLY_PROP_CHARGE_TYPE)
96 		return sprintf(buf, "%s\n", charge_type[value.intval]);
97 	else if (off == POWER_SUPPLY_PROP_HEALTH)
98 		return sprintf(buf, "%s\n", health_text[value.intval]);
99 	else if (off == POWER_SUPPLY_PROP_TECHNOLOGY)
100 		return sprintf(buf, "%s\n", technology_text[value.intval]);
101 	else if (off == POWER_SUPPLY_PROP_CAPACITY_LEVEL)
102 		return sprintf(buf, "%s\n", capacity_level_text[value.intval]);
103 	else if (off == POWER_SUPPLY_PROP_TYPE)
104 		return sprintf(buf, "%s\n", type_text[value.intval]);
105 	else if (off == POWER_SUPPLY_PROP_SCOPE)
106 		return sprintf(buf, "%s\n", scope_text[value.intval]);
107 	else if (off >= POWER_SUPPLY_PROP_MODEL_NAME)
108 		return sprintf(buf, "%s\n", value.strval);
109 
110 	return sprintf(buf, "%d\n", value.intval);
111 }
112 
113 static ssize_t power_supply_store_property(struct device *dev,
114 					   struct device_attribute *attr,
115 					   const char *buf, size_t count) {
116 	ssize_t ret;
117 	struct power_supply *psy = dev_get_drvdata(dev);
118 	const ptrdiff_t off = attr - power_supply_attrs;
119 	union power_supply_propval value;
120 	long long_val;
121 
122 	/* TODO: support other types than int */
123 	ret = kstrtol(buf, 10, &long_val);
124 	if (ret < 0)
125 		return ret;
126 
127 	value.intval = long_val;
128 
129 	ret = power_supply_set_property(psy, off, &value);
130 	if (ret < 0)
131 		return ret;
132 
133 	return count;
134 }
135 
136 /* Must be in the same order as POWER_SUPPLY_PROP_* */
137 static struct device_attribute power_supply_attrs[] = {
138 	/* Properties of type `int' */
139 	POWER_SUPPLY_ATTR(status),
140 	POWER_SUPPLY_ATTR(charge_type),
141 	POWER_SUPPLY_ATTR(health),
142 	POWER_SUPPLY_ATTR(present),
143 	POWER_SUPPLY_ATTR(online),
144 	POWER_SUPPLY_ATTR(authentic),
145 	POWER_SUPPLY_ATTR(technology),
146 	POWER_SUPPLY_ATTR(cycle_count),
147 	POWER_SUPPLY_ATTR(voltage_max),
148 	POWER_SUPPLY_ATTR(voltage_min),
149 	POWER_SUPPLY_ATTR(voltage_max_design),
150 	POWER_SUPPLY_ATTR(voltage_min_design),
151 	POWER_SUPPLY_ATTR(voltage_now),
152 	POWER_SUPPLY_ATTR(voltage_avg),
153 	POWER_SUPPLY_ATTR(voltage_ocv),
154 	POWER_SUPPLY_ATTR(voltage_boot),
155 	POWER_SUPPLY_ATTR(current_max),
156 	POWER_SUPPLY_ATTR(current_now),
157 	POWER_SUPPLY_ATTR(current_avg),
158 	POWER_SUPPLY_ATTR(current_boot),
159 	POWER_SUPPLY_ATTR(power_now),
160 	POWER_SUPPLY_ATTR(power_avg),
161 	POWER_SUPPLY_ATTR(charge_full_design),
162 	POWER_SUPPLY_ATTR(charge_empty_design),
163 	POWER_SUPPLY_ATTR(charge_full),
164 	POWER_SUPPLY_ATTR(charge_empty),
165 	POWER_SUPPLY_ATTR(charge_now),
166 	POWER_SUPPLY_ATTR(charge_avg),
167 	POWER_SUPPLY_ATTR(charge_counter),
168 	POWER_SUPPLY_ATTR(constant_charge_current),
169 	POWER_SUPPLY_ATTR(constant_charge_current_max),
170 	POWER_SUPPLY_ATTR(constant_charge_voltage),
171 	POWER_SUPPLY_ATTR(constant_charge_voltage_max),
172 	POWER_SUPPLY_ATTR(charge_control_limit),
173 	POWER_SUPPLY_ATTR(charge_control_limit_max),
174 	POWER_SUPPLY_ATTR(input_current_limit),
175 	POWER_SUPPLY_ATTR(energy_full_design),
176 	POWER_SUPPLY_ATTR(energy_empty_design),
177 	POWER_SUPPLY_ATTR(energy_full),
178 	POWER_SUPPLY_ATTR(energy_empty),
179 	POWER_SUPPLY_ATTR(energy_now),
180 	POWER_SUPPLY_ATTR(energy_avg),
181 	POWER_SUPPLY_ATTR(capacity),
182 	POWER_SUPPLY_ATTR(capacity_alert_min),
183 	POWER_SUPPLY_ATTR(capacity_alert_max),
184 	POWER_SUPPLY_ATTR(capacity_level),
185 	POWER_SUPPLY_ATTR(temp),
186 	POWER_SUPPLY_ATTR(temp_max),
187 	POWER_SUPPLY_ATTR(temp_min),
188 	POWER_SUPPLY_ATTR(temp_alert_min),
189 	POWER_SUPPLY_ATTR(temp_alert_max),
190 	POWER_SUPPLY_ATTR(temp_ambient),
191 	POWER_SUPPLY_ATTR(temp_ambient_alert_min),
192 	POWER_SUPPLY_ATTR(temp_ambient_alert_max),
193 	POWER_SUPPLY_ATTR(time_to_empty_now),
194 	POWER_SUPPLY_ATTR(time_to_empty_avg),
195 	POWER_SUPPLY_ATTR(time_to_full_now),
196 	POWER_SUPPLY_ATTR(time_to_full_avg),
197 	POWER_SUPPLY_ATTR(type),
198 	POWER_SUPPLY_ATTR(scope),
199 	POWER_SUPPLY_ATTR(charge_term_current),
200 	POWER_SUPPLY_ATTR(calibrate),
201 	/* Properties of type `const char *' */
202 	POWER_SUPPLY_ATTR(model_name),
203 	POWER_SUPPLY_ATTR(manufacturer),
204 	POWER_SUPPLY_ATTR(serial_number),
205 };
206 
207 static struct attribute *
208 __power_supply_attrs[ARRAY_SIZE(power_supply_attrs) + 1];
209 
210 static umode_t power_supply_attr_is_visible(struct kobject *kobj,
211 					   struct attribute *attr,
212 					   int attrno)
213 {
214 	struct device *dev = container_of(kobj, struct device, kobj);
215 	struct power_supply *psy = dev_get_drvdata(dev);
216 	umode_t mode = S_IRUSR | S_IRGRP | S_IROTH;
217 	int i;
218 
219 	if (attrno == POWER_SUPPLY_PROP_TYPE)
220 		return mode;
221 
222 	for (i = 0; i < psy->desc->num_properties; i++) {
223 		int property = psy->desc->properties[i];
224 
225 		if (property == attrno) {
226 			if (psy->desc->property_is_writeable &&
227 			    psy->desc->property_is_writeable(psy, property) > 0)
228 				mode |= S_IWUSR;
229 
230 			return mode;
231 		}
232 	}
233 
234 	return 0;
235 }
236 
237 static struct attribute_group power_supply_attr_group = {
238 	.attrs = __power_supply_attrs,
239 	.is_visible = power_supply_attr_is_visible,
240 };
241 
242 static const struct attribute_group *power_supply_attr_groups[] = {
243 	&power_supply_attr_group,
244 	NULL,
245 };
246 
247 void power_supply_init_attrs(struct device_type *dev_type)
248 {
249 	int i;
250 
251 	dev_type->groups = power_supply_attr_groups;
252 
253 	for (i = 0; i < ARRAY_SIZE(power_supply_attrs); i++)
254 		__power_supply_attrs[i] = &power_supply_attrs[i].attr;
255 }
256 
257 static char *kstruprdup(const char *str, gfp_t gfp)
258 {
259 	char *ret, *ustr;
260 
261 	ustr = ret = kmalloc(strlen(str) + 1, gfp);
262 
263 	if (!ret)
264 		return NULL;
265 
266 	while (*str)
267 		*ustr++ = toupper(*str++);
268 
269 	*ustr = 0;
270 
271 	return ret;
272 }
273 
274 int power_supply_uevent(struct device *dev, struct kobj_uevent_env *env)
275 {
276 	struct power_supply *psy = dev_get_drvdata(dev);
277 	int ret = 0, j;
278 	char *prop_buf;
279 	char *attrname;
280 
281 	dev_dbg(dev, "uevent\n");
282 
283 	if (!psy || !psy->desc) {
284 		dev_dbg(dev, "No power supply yet\n");
285 		return ret;
286 	}
287 
288 	dev_dbg(dev, "POWER_SUPPLY_NAME=%s\n", psy->desc->name);
289 
290 	ret = add_uevent_var(env, "POWER_SUPPLY_NAME=%s", psy->desc->name);
291 	if (ret)
292 		return ret;
293 
294 	prop_buf = (char *)get_zeroed_page(GFP_KERNEL);
295 	if (!prop_buf)
296 		return -ENOMEM;
297 
298 	for (j = 0; j < psy->desc->num_properties; j++) {
299 		struct device_attribute *attr;
300 		char *line;
301 
302 		attr = &power_supply_attrs[psy->desc->properties[j]];
303 
304 		ret = power_supply_show_property(dev, attr, prop_buf);
305 		if (ret == -ENODEV || ret == -ENODATA) {
306 			/* When a battery is absent, we expect -ENODEV. Don't abort;
307 			   send the uevent with at least the the PRESENT=0 property */
308 			ret = 0;
309 			continue;
310 		}
311 
312 		if (ret < 0)
313 			goto out;
314 
315 		line = strchr(prop_buf, '\n');
316 		if (line)
317 			*line = 0;
318 
319 		attrname = kstruprdup(attr->attr.name, GFP_KERNEL);
320 		if (!attrname) {
321 			ret = -ENOMEM;
322 			goto out;
323 		}
324 
325 		dev_dbg(dev, "prop %s=%s\n", attrname, prop_buf);
326 
327 		ret = add_uevent_var(env, "POWER_SUPPLY_%s=%s", attrname, prop_buf);
328 		kfree(attrname);
329 		if (ret)
330 			goto out;
331 	}
332 
333 out:
334 	free_page((unsigned long)prop_buf);
335 
336 	return ret;
337 }
338