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