drivers/power/supply/power_supply_sysfs.c

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