drivers/power/supply/power_supply_sysfs.c

   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(input_voltage_limit),
 280         POWER_SUPPLY_ATTR(input_power_limit),
 281         POWER_SUPPLY_ATTR(energy_full_design),
 282         POWER_SUPPLY_ATTR(energy_empty_design),
 283         POWER_SUPPLY_ATTR(energy_full),
 284         POWER_SUPPLY_ATTR(energy_empty),
 285         POWER_SUPPLY_ATTR(energy_now),
 286         POWER_SUPPLY_ATTR(energy_avg),
 287         POWER_SUPPLY_ATTR(capacity),
 288         POWER_SUPPLY_ATTR(capacity_alert_min),
 289         POWER_SUPPLY_ATTR(capacity_alert_max),
 290         POWER_SUPPLY_ATTR(capacity_level),
 291         POWER_SUPPLY_ATTR(temp),
 292         POWER_SUPPLY_ATTR(temp_max),
 293         POWER_SUPPLY_ATTR(temp_min),
 294         POWER_SUPPLY_ATTR(temp_alert_min),
 295         POWER_SUPPLY_ATTR(temp_alert_max),
 296         POWER_SUPPLY_ATTR(temp_ambient),
 297         POWER_SUPPLY_ATTR(temp_ambient_alert_min),
 298         POWER_SUPPLY_ATTR(temp_ambient_alert_max),
 299         POWER_SUPPLY_ATTR(time_to_empty_now),
 300         POWER_SUPPLY_ATTR(time_to_empty_avg),
 301         POWER_SUPPLY_ATTR(time_to_full_now),
 302         POWER_SUPPLY_ATTR(time_to_full_avg),
 303         POWER_SUPPLY_ATTR(type),
 304         POWER_SUPPLY_ATTR(usb_type),
 305         POWER_SUPPLY_ATTR(scope),
 306         POWER_SUPPLY_ATTR(precharge_current),
 307         POWER_SUPPLY_ATTR(charge_term_current),
 308         POWER_SUPPLY_ATTR(calibrate),
 309         /* Properties of type `const char *' */
 310         POWER_SUPPLY_ATTR(model_name),
 311         POWER_SUPPLY_ATTR(manufacturer),
 312         POWER_SUPPLY_ATTR(serial_number),
 313 };
 314
 315 static struct attribute *
 316 __power_supply_attrs[ARRAY_SIZE(power_supply_attrs) + 1];
 317
 318 static umode_t power_supply_attr_is_visible(struct kobject *kobj,
 319                                            struct attribute *attr,
 320                                            int attrno)
 321 {
 322         struct device *dev = container_of(kobj, struct device, kobj);
 323         struct power_supply *psy = dev_get_drvdata(dev);
 324         umode_t mode = S_IRUSR | S_IRGRP | S_IROTH;
 325         int i;
 326
 327         if (attrno == POWER_SUPPLY_PROP_TYPE)
 328                 return mode;
 329
 330         for (i = 0; i < psy->desc->num_properties; i++) {
 331                 int property = psy->desc->properties[i];
 332
 333                 if (property == attrno) {
 334                         if (psy->desc->property_is_writeable &&
 335                             psy->desc->property_is_writeable(psy, property) > 0)
 336                                 mode |= S_IWUSR;
 337
 338                         return mode;
 339                 }
 340         }
 341
 342         return 0;
 343 }
 344
 345 static struct attribute_group power_supply_attr_group = {
 346         .attrs = __power_supply_attrs,
 347         .is_visible = power_supply_attr_is_visible,
 348 };
 349
 350 static const struct attribute_group *power_supply_attr_groups[] = {
 351         &power_supply_attr_group,
 352         NULL,
 353 };
 354
 355 void power_supply_init_attrs(struct device_type *dev_type)
 356 {
 357         int i;
 358
 359         dev_type->groups = power_supply_attr_groups;
 360
 361         for (i = 0; i < ARRAY_SIZE(power_supply_attrs); i++)
 362                 __power_supply_attrs[i] = &power_supply_attrs[i].attr;
 363 }
 364
 365 static char *kstruprdup(const char *str, gfp_t gfp)
 366 {
 367         char *ret, *ustr;
 368
 369         ustr = ret = kmalloc(strlen(str) + 1, gfp);
 370
 371         if (!ret)
 372                 return NULL;
 373
 374         while (*str)
 375                 *ustr++ = toupper(*str++);
 376
 377         *ustr = 0;
 378
 379         return ret;
 380 }
 381
 382 int power_supply_uevent(struct device *dev, struct kobj_uevent_env *env)
 383 {
 384         struct power_supply *psy = dev_get_drvdata(dev);
 385         int ret = 0, j;
 386         char *prop_buf;
 387         char *attrname;
 388
 389         if (!psy || !psy->desc) {
 390                 dev_dbg(dev, "No power supply yet\n");
 391                 return ret;
 392         }
 393
 394         ret = add_uevent_var(env, "POWER_SUPPLY_NAME=%s", psy->desc->name);
 395         if (ret)
 396                 return ret;
 397
 398         prop_buf = (char *)get_zeroed_page(GFP_KERNEL);
 399         if (!prop_buf)
 400                 return -ENOMEM;
 401
 402         for (j = 0; j < psy->desc->num_properties; j++) {
 403                 struct device_attribute *attr;
 404                 char *line;
 405
 406                 attr = &power_supply_attrs[psy->desc->properties[j]];
 407
 408                 ret = power_supply_show_property(dev, attr, prop_buf);
 409                 if (ret == -ENODEV || ret == -ENODATA) {
 410                         /* When a battery is absent, we expect -ENODEV. Don't abort;
 411                            send the uevent with at least the the PRESENT=0 property */
 412                         ret = 0;
 413                         continue;
 414                 }
 415
 416                 if (ret < 0)
 417                         goto out;
 418
 419                 line = strchr(prop_buf, '\n');
 420                 if (line)
 421                         *line = 0;
 422
 423                 attrname = kstruprdup(attr->attr.name, GFP_KERNEL);
 424                 if (!attrname) {
 425                         ret = -ENOMEM;
 426                         goto out;
 427                 }
 428
 429                 ret = add_uevent_var(env, "POWER_SUPPLY_%s=%s", attrname, prop_buf);
 430                 kfree(attrname);
 431                 if (ret)
 432                         goto out;
 433         }
 434
 435 out:
 436         free_page((unsigned long)prop_buf);
 437
 438         return ret;
 439 }