drivers/iio/industrialio-core.c

   1 /* The industrial I/O core
   2  *
   3  * Copyright (c) 2008 Jonathan Cameron
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published by
   7  * the Free Software Foundation.
   8  *
   9  * Based on elements of hwmon and input subsystems.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include <linux/idr.h>
  15 #include <linux/kdev_t.h>
  16 #include <linux/err.h>
  17 #include <linux/device.h>
  18 #include <linux/fs.h>
  19 #include <linux/poll.h>
  20 #include <linux/sched.h>
  21 #include <linux/wait.h>
  22 #include <linux/cdev.h>
  23 #include <linux/slab.h>
  24 #include <linux/anon_inodes.h>
  25 #include <linux/debugfs.h>
  26 #include <linux/iio/iio.h>
  27 #include "iio_core.h"
  28 #include "iio_core_trigger.h"
  29 #include <linux/iio/sysfs.h>
  30 #include <linux/iio/events.h>
  31
  32 /* IDA to assign each registered device a unique id */
  33 static DEFINE_IDA(iio_ida);
  34
  35 static dev_t iio_devt;
  36
  37 #define IIO_DEV_MAX 256
  38 struct bus_type iio_bus_type = {
  39         .name = "iio",
  40 };
  41 EXPORT_SYMBOL(iio_bus_type);
  42
  43 static struct dentry *iio_debugfs_dentry;
  44
  45 static const char * const iio_direction[] = {
  46         [0] = "in",
  47         [1] = "out",
  48 };
  49
  50 static const char * const iio_chan_type_name_spec[] = {
  51         [IIO_VOLTAGE] = "voltage",
  52         [IIO_CURRENT] = "current",
  53         [IIO_POWER] = "power",
  54         [IIO_ACCEL] = "accel",
  55         [IIO_ANGL_VEL] = "anglvel",
  56         [IIO_MAGN] = "magn",
  57         [IIO_LIGHT] = "illuminance",
  58         [IIO_INTENSITY] = "intensity",
  59         [IIO_PROXIMITY] = "proximity",
  60         [IIO_TEMP] = "temp",
  61         [IIO_INCLI] = "incli",
  62         [IIO_ROT] = "rot",
  63         [IIO_ANGL] = "angl",
  64         [IIO_TIMESTAMP] = "timestamp",
  65         [IIO_CAPACITANCE] = "capacitance",
  66         [IIO_ALTVOLTAGE] = "altvoltage",
  67         [IIO_CCT] = "cct",
  68         [IIO_PRESSURE] = "pressure",
  69         [IIO_QUATERNION] = "quaternion",
  70 };
  71
  72 static const char * const iio_modifier_names[] = {
  73         [IIO_MOD_X] = "x",
  74         [IIO_MOD_Y] = "y",
  75         [IIO_MOD_Z] = "z",
  76         [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
  77         [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
  78         [IIO_MOD_LIGHT_BOTH] = "both",
  79         [IIO_MOD_LIGHT_IR] = "ir",
  80         [IIO_MOD_LIGHT_CLEAR] = "clear",
  81         [IIO_MOD_LIGHT_RED] = "red",
  82         [IIO_MOD_LIGHT_GREEN] = "green",
  83         [IIO_MOD_LIGHT_BLUE] = "blue",
  84         [IIO_MOD_R]  = "r",
  85 };
  86
  87 /* relies on pairs of these shared then separate */
  88 static const char * const iio_chan_info_postfix[] = {
  89         [IIO_CHAN_INFO_RAW] = "raw",
  90         [IIO_CHAN_INFO_PROCESSED] = "input",
  91         [IIO_CHAN_INFO_SCALE] = "scale",
  92         [IIO_CHAN_INFO_OFFSET] = "offset",
  93         [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
  94         [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
  95         [IIO_CHAN_INFO_PEAK] = "peak_raw",
  96         [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
  97         [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
  98         [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
  99         [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
 100         = "filter_low_pass_3db_frequency",
 101         [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
 102         [IIO_CHAN_INFO_FREQUENCY] = "frequency",
 103         [IIO_CHAN_INFO_PHASE] = "phase",
 104         [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
 105         [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
 106 };
 107
 108 const struct iio_chan_spec
 109 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
 110 {
 111         int i;
 112
 113         for (i = 0; i < indio_dev->num_channels; i++)
 114                 if (indio_dev->channels[i].scan_index == si)
 115                         return &indio_dev->channels[i];
 116         return NULL;
 117 }
 118
 119 /* This turns up an awful lot */
 120 ssize_t iio_read_const_attr(struct device *dev,
 121                             struct device_attribute *attr,
 122                             char *buf)
 123 {
 124         return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
 125 }
 126 EXPORT_SYMBOL(iio_read_const_attr);
 127
 128 static int __init iio_init(void)
 129 {
 130         int ret;
 131
 132         /* Register sysfs bus */
 133         ret  = bus_register(&iio_bus_type);
 134         if (ret < 0) {
 135                 printk(KERN_ERR
 136                        "%s could not register bus type\n",
 137                         __FILE__);
 138                 goto error_nothing;
 139         }
 140
 141         ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
 142         if (ret < 0) {
 143                 printk(KERN_ERR "%s: failed to allocate char dev region\n",
 144                        __FILE__);
 145                 goto error_unregister_bus_type;
 146         }
 147
 148         iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
 149
 150         return 0;
 151
 152 error_unregister_bus_type:
 153         bus_unregister(&iio_bus_type);
 154 error_nothing:
 155         return ret;
 156 }
 157
 158 static void __exit iio_exit(void)
 159 {
 160         if (iio_devt)
 161                 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
 162         bus_unregister(&iio_bus_type);
 163         debugfs_remove(iio_debugfs_dentry);
 164 }
 165
 166 #if defined(CONFIG_DEBUG_FS)
 167 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
 168                               size_t count, loff_t *ppos)
 169 {
 170         struct iio_dev *indio_dev = file->private_data;
 171         char buf[20];
 172         unsigned val = 0;
 173         ssize_t len;
 174         int ret;
 175
 176         ret = indio_dev->info->debugfs_reg_access(indio_dev,
 177                                                   indio_dev->cached_reg_addr,
 178                                                   0, &val);
 179         if (ret)
 180                 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
 181
 182         len = snprintf(buf, sizeof(buf), "0x%X\n", val);
 183
 184         return simple_read_from_buffer(userbuf, count, ppos, buf, len);
 185 }
 186
 187 static ssize_t iio_debugfs_write_reg(struct file *file,
 188                      const char __user *userbuf, size_t count, loff_t *ppos)
 189 {
 190         struct iio_dev *indio_dev = file->private_data;
 191         unsigned reg, val;
 192         char buf[80];
 193         int ret;
 194
 195         count = min_t(size_t, count, (sizeof(buf)-1));
 196         if (copy_from_user(buf, userbuf, count))
 197                 return -EFAULT;
 198
 199         buf[count] = 0;
 200
 201         ret = sscanf(buf, "%i %i", &reg, &val);
 202
 203         switch (ret) {
 204         case 1:
 205                 indio_dev->cached_reg_addr = reg;
 206                 break;
 207         case 2:
 208                 indio_dev->cached_reg_addr = reg;
 209                 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
 210                                                           val, NULL);
 211                 if (ret) {
 212                         dev_err(indio_dev->dev.parent, "%s: write failed\n",
 213                                 __func__);
 214                         return ret;
 215                 }
 216                 break;
 217         default:
 218                 return -EINVAL;
 219         }
 220
 221         return count;
 222 }
 223
 224 static const struct file_operations iio_debugfs_reg_fops = {
 225         .open = simple_open,
 226         .read = iio_debugfs_read_reg,
 227         .write = iio_debugfs_write_reg,
 228 };
 229
 230 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
 231 {
 232         debugfs_remove_recursive(indio_dev->debugfs_dentry);
 233 }
 234
 235 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
 236 {
 237         struct dentry *d;
 238
 239         if (indio_dev->info->debugfs_reg_access == NULL)
 240                 return 0;
 241
 242         if (!iio_debugfs_dentry)
 243                 return 0;
 244
 245         indio_dev->debugfs_dentry =
 246                 debugfs_create_dir(dev_name(&indio_dev->dev),
 247                                    iio_debugfs_dentry);
 248         if (indio_dev->debugfs_dentry == NULL) {
 249                 dev_warn(indio_dev->dev.parent,
 250                          "Failed to create debugfs directory\n");
 251                 return -EFAULT;
 252         }
 253
 254         d = debugfs_create_file("direct_reg_access", 0644,
 255                                 indio_dev->debugfs_dentry,
 256                                 indio_dev, &iio_debugfs_reg_fops);
 257         if (!d) {
 258                 iio_device_unregister_debugfs(indio_dev);
 259                 return -ENOMEM;
 260         }
 261
 262         return 0;
 263 }
 264 #else
 265 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
 266 {
 267         return 0;
 268 }
 269
 270 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
 271 {
 272 }
 273 #endif /* CONFIG_DEBUG_FS */
 274
 275 static ssize_t iio_read_channel_ext_info(struct device *dev,
 276                                      struct device_attribute *attr,
 277                                      char *buf)
 278 {
 279         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 280         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 281         const struct iio_chan_spec_ext_info *ext_info;
 282
 283         ext_info = &this_attr->c->ext_info[this_attr->address];
 284
 285         return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
 286 }
 287
 288 static ssize_t iio_write_channel_ext_info(struct device *dev,
 289                                      struct device_attribute *attr,
 290                                      const char *buf,
 291                                          size_t len)
 292 {
 293         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 294         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 295         const struct iio_chan_spec_ext_info *ext_info;
 296
 297         ext_info = &this_attr->c->ext_info[this_attr->address];
 298
 299         return ext_info->write(indio_dev, ext_info->private,
 300                                this_attr->c, buf, len);
 301 }
 302
 303 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
 304         uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
 305 {
 306         const struct iio_enum *e = (const struct iio_enum *)priv;
 307         unsigned int i;
 308         size_t len = 0;
 309
 310         if (!e->num_items)
 311                 return 0;
 312
 313         for (i = 0; i < e->num_items; ++i)
 314                 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
 315
 316         /* replace last space with a newline */
 317         buf[len - 1] = '\n';
 318
 319         return len;
 320 }
 321 EXPORT_SYMBOL_GPL(iio_enum_available_read);
 322
 323 ssize_t iio_enum_read(struct iio_dev *indio_dev,
 324         uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
 325 {
 326         const struct iio_enum *e = (const struct iio_enum *)priv;
 327         int i;
 328
 329         if (!e->get)
 330                 return -EINVAL;
 331
 332         i = e->get(indio_dev, chan);
 333         if (i < 0)
 334                 return i;
 335         else if (i >= e->num_items)
 336                 return -EINVAL;
 337
 338         return sprintf(buf, "%s\n", e->items[i]);
 339 }
 340 EXPORT_SYMBOL_GPL(iio_enum_read);
 341
 342 ssize_t iio_enum_write(struct iio_dev *indio_dev,
 343         uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
 344         size_t len)
 345 {
 346         const struct iio_enum *e = (const struct iio_enum *)priv;
 347         unsigned int i;
 348         int ret;
 349
 350         if (!e->set)
 351                 return -EINVAL;
 352
 353         for (i = 0; i < e->num_items; i++) {
 354                 if (sysfs_streq(buf, e->items[i]))
 355                         break;
 356         }
 357
 358         if (i == e->num_items)
 359                 return -EINVAL;
 360
 361         ret = e->set(indio_dev, chan, i);
 362         return ret ? ret : len;
 363 }
 364 EXPORT_SYMBOL_GPL(iio_enum_write);
 365
 366 static ssize_t iio_read_channel_info(struct device *dev,
 367                                      struct device_attribute *attr,
 368                                      char *buf)
 369 {
 370         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 371         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 372         unsigned long long tmp;
 373         int val, val2;
 374         bool scale_db = false;
 375         int ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
 376                                             &val, &val2, this_attr->address);
 377
 378         if (ret < 0)
 379                 return ret;
 380
 381         switch (ret) {
 382         case IIO_VAL_INT:
 383                 return sprintf(buf, "%d\n", val);
 384         case IIO_VAL_INT_PLUS_MICRO_DB:
 385                 scale_db = true;
 386         case IIO_VAL_INT_PLUS_MICRO:
 387                 if (val2 < 0)
 388                         return sprintf(buf, "-%d.%06u%s\n", val, -val2,
 389                                 scale_db ? " dB" : "");
 390                 else
 391                         return sprintf(buf, "%d.%06u%s\n", val, val2,
 392                                 scale_db ? " dB" : "");
 393         case IIO_VAL_INT_PLUS_NANO:
 394                 if (val2 < 0)
 395                         return sprintf(buf, "-%d.%09u\n", val, -val2);
 396                 else
 397                         return sprintf(buf, "%d.%09u\n", val, val2);
 398         case IIO_VAL_FRACTIONAL:
 399                 tmp = div_s64((s64)val * 1000000000LL, val2);
 400                 val2 = do_div(tmp, 1000000000LL);
 401                 val = tmp;
 402                 return sprintf(buf, "%d.%09u\n", val, val2);
 403         case IIO_VAL_FRACTIONAL_LOG2:
 404                 tmp = (s64)val * 1000000000LL >> val2;
 405                 val2 = do_div(tmp, 1000000000LL);
 406                 val = tmp;
 407                 return sprintf(buf, "%d.%09u\n", val, val2);
 408         default:
 409                 return 0;
 410         }
 411 }
 412
 413 /**
 414  * iio_str_to_fixpoint() - Parse a fixed-point number from a string
 415  * @str: The string to parse
 416  * @fract_mult: Multiplier for the first decimal place, should be a power of 10
 417  * @integer: The integer part of the number
 418  * @fract: The fractional part of the number
 419  *
 420  * Returns 0 on success, or a negative error code if the string could not be
 421  * parsed.
 422  */
 423 int iio_str_to_fixpoint(const char *str, int fract_mult,
 424         int *integer, int *fract)
 425 {
 426         int i = 0, f = 0;
 427         bool integer_part = true, negative = false;
 428
 429         if (str[0] == '-') {
 430                 negative = true;
 431                 str++;
 432         } else if (str[0] == '+') {
 433                 str++;
 434         }
 435
 436         while (*str) {
 437                 if ('0' <= *str && *str <= '9') {
 438                         if (integer_part) {
 439                                 i = i * 10 + *str - '0';
 440                         } else {
 441                                 f += fract_mult * (*str - '0');
 442                                 fract_mult /= 10;
 443                         }
 444                 } else if (*str == '\n') {
 445                         if (*(str + 1) == '\0')
 446                                 break;
 447                         else
 448                                 return -EINVAL;
 449                 } else if (*str == '.' && integer_part) {
 450                         integer_part = false;
 451                 } else {
 452                         return -EINVAL;
 453                 }
 454                 str++;
 455         }
 456
 457         if (negative) {
 458                 if (i)
 459                         i = -i;
 460                 else
 461                         f = -f;
 462         }
 463
 464         *integer = i;
 465         *fract = f;
 466
 467         return 0;
 468 }
 469 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
 470
 471 static ssize_t iio_write_channel_info(struct device *dev,
 472                                       struct device_attribute *attr,
 473                                       const char *buf,
 474                                       size_t len)
 475 {
 476         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 477         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 478         int ret, fract_mult = 100000;
 479         int integer, fract;
 480
 481         /* Assumes decimal - precision based on number of digits */
 482         if (!indio_dev->info->write_raw)
 483                 return -EINVAL;
 484
 485         if (indio_dev->info->write_raw_get_fmt)
 486                 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
 487                         this_attr->c, this_attr->address)) {
 488                 case IIO_VAL_INT_PLUS_MICRO:
 489                         fract_mult = 100000;
 490                         break;
 491                 case IIO_VAL_INT_PLUS_NANO:
 492                         fract_mult = 100000000;
 493                         break;
 494                 default:
 495                         return -EINVAL;
 496                 }
 497
 498         ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
 499         if (ret)
 500                 return ret;
 501
 502         ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
 503                                          integer, fract, this_attr->address);
 504         if (ret)
 505                 return ret;
 506
 507         return len;
 508 }
 509
 510 static
 511 int __iio_device_attr_init(struct device_attribute *dev_attr,
 512                            const char *postfix,
 513                            struct iio_chan_spec const *chan,
 514                            ssize_t (*readfunc)(struct device *dev,
 515                                                struct device_attribute *attr,
 516                                                char *buf),
 517                            ssize_t (*writefunc)(struct device *dev,
 518                                                 struct device_attribute *attr,
 519                                                 const char *buf,
 520                                                 size_t len),
 521                            bool generic)
 522 {
 523         int ret;
 524         char *name_format, *full_postfix;
 525         sysfs_attr_init(&dev_attr->attr);
 526
 527         /* Build up postfix of <extend_name>_<modifier>_postfix */
 528         if (chan->modified && !generic) {
 529                 if (chan->extend_name)
 530                         full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
 531                                                  iio_modifier_names[chan
 532                                                                     ->channel2],
 533                                                  chan->extend_name,
 534                                                  postfix);
 535                 else
 536                         full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
 537                                                  iio_modifier_names[chan
 538                                                                     ->channel2],
 539                                                  postfix);
 540         } else {
 541                 if (chan->extend_name == NULL)
 542                         full_postfix = kstrdup(postfix, GFP_KERNEL);
 543                 else
 544                         full_postfix = kasprintf(GFP_KERNEL,
 545                                                  "%s_%s",
 546                                                  chan->extend_name,
 547                                                  postfix);
 548         }
 549         if (full_postfix == NULL) {
 550                 ret = -ENOMEM;
 551                 goto error_ret;
 552         }
 553
 554         if (chan->differential) { /* Differential can not have modifier */
 555                 if (generic)
 556                         name_format
 557                                 = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
 558                                             iio_direction[chan->output],
 559                                             iio_chan_type_name_spec[chan->type],
 560                                             iio_chan_type_name_spec[chan->type],
 561                                             full_postfix);
 562                 else if (chan->indexed)
 563                         name_format
 564                                 = kasprintf(GFP_KERNEL, "%s_%s%d-%s%d_%s",
 565                                             iio_direction[chan->output],
 566                                             iio_chan_type_name_spec[chan->type],
 567                                             chan->channel,
 568                                             iio_chan_type_name_spec[chan->type],
 569                                             chan->channel2,
 570                                             full_postfix);
 571                 else {
 572                         WARN_ON("Differential channels must be indexed\n");
 573                         ret = -EINVAL;
 574                         goto error_free_full_postfix;
 575                 }
 576         } else { /* Single ended */
 577                 if (generic)
 578                         name_format
 579                                 = kasprintf(GFP_KERNEL, "%s_%s_%s",
 580                                             iio_direction[chan->output],
 581                                             iio_chan_type_name_spec[chan->type],
 582                                             full_postfix);
 583                 else if (chan->indexed)
 584                         name_format
 585                                 = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
 586                                             iio_direction[chan->output],
 587                                             iio_chan_type_name_spec[chan->type],
 588                                             chan->channel,
 589                                             full_postfix);
 590                 else
 591                         name_format
 592                                 = kasprintf(GFP_KERNEL, "%s_%s_%s",
 593                                             iio_direction[chan->output],
 594                                             iio_chan_type_name_spec[chan->type],
 595                                             full_postfix);
 596         }
 597         if (name_format == NULL) {
 598                 ret = -ENOMEM;
 599                 goto error_free_full_postfix;
 600         }
 601         dev_attr->attr.name = kasprintf(GFP_KERNEL,
 602                                         name_format,
 603                                         chan->channel,
 604                                         chan->channel2);
 605         if (dev_attr->attr.name == NULL) {
 606                 ret = -ENOMEM;
 607                 goto error_free_name_format;
 608         }
 609
 610         if (readfunc) {
 611                 dev_attr->attr.mode |= S_IRUGO;
 612                 dev_attr->show = readfunc;
 613         }
 614
 615         if (writefunc) {
 616                 dev_attr->attr.mode |= S_IWUSR;
 617                 dev_attr->store = writefunc;
 618         }
 619         kfree(name_format);
 620         kfree(full_postfix);
 621
 622         return 0;
 623
 624 error_free_name_format:
 625         kfree(name_format);
 626 error_free_full_postfix:
 627         kfree(full_postfix);
 628 error_ret:
 629         return ret;
 630 }
 631
 632 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
 633 {
 634         kfree(dev_attr->attr.name);
 635 }
 636
 637 int __iio_add_chan_devattr(const char *postfix,
 638                            struct iio_chan_spec const *chan,
 639                            ssize_t (*readfunc)(struct device *dev,
 640                                                struct device_attribute *attr,
 641                                                char *buf),
 642                            ssize_t (*writefunc)(struct device *dev,
 643                                                 struct device_attribute *attr,
 644                                                 const char *buf,
 645                                                 size_t len),
 646                            u64 mask,
 647                            bool generic,
 648                            struct device *dev,
 649                            struct list_head *attr_list)
 650 {
 651         int ret;
 652         struct iio_dev_attr *iio_attr, *t;
 653
 654         iio_attr = kzalloc(sizeof *iio_attr, GFP_KERNEL);
 655         if (iio_attr == NULL) {
 656                 ret = -ENOMEM;
 657                 goto error_ret;
 658         }
 659         ret = __iio_device_attr_init(&iio_attr->dev_attr,
 660                                      postfix, chan,
 661                                      readfunc, writefunc, generic);
 662         if (ret)
 663                 goto error_iio_dev_attr_free;
 664         iio_attr->c = chan;
 665         iio_attr->address = mask;
 666         list_for_each_entry(t, attr_list, l)
 667                 if (strcmp(t->dev_attr.attr.name,
 668                            iio_attr->dev_attr.attr.name) == 0) {
 669                         if (!generic)
 670                                 dev_err(dev, "tried to double register : %s\n",
 671                                         t->dev_attr.attr.name);
 672                         ret = -EBUSY;
 673                         goto error_device_attr_deinit;
 674                 }
 675         list_add(&iio_attr->l, attr_list);
 676
 677         return 0;
 678
 679 error_device_attr_deinit:
 680         __iio_device_attr_deinit(&iio_attr->dev_attr);
 681 error_iio_dev_attr_free:
 682         kfree(iio_attr);
 683 error_ret:
 684         return ret;
 685 }
 686
 687 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
 688                                         struct iio_chan_spec const *chan)
 689 {
 690         int ret, attrcount = 0;
 691         int i;
 692         const struct iio_chan_spec_ext_info *ext_info;
 693
 694         if (chan->channel < 0)
 695                 return 0;
 696         for_each_set_bit(i, &chan->info_mask_separate, sizeof(long)*8) {
 697                 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
 698                                              chan,
 699                                              &iio_read_channel_info,
 700                                              &iio_write_channel_info,
 701                                              i,
 702                                              0,
 703                                              &indio_dev->dev,
 704                                              &indio_dev->channel_attr_list);
 705                 if (ret < 0)
 706                         goto error_ret;
 707                 attrcount++;
 708         }
 709         for_each_set_bit(i, &chan->info_mask_shared_by_type, sizeof(long)*8) {
 710                 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
 711                                              chan,
 712                                              &iio_read_channel_info,
 713                                              &iio_write_channel_info,
 714                                              i,
 715                                              1,
 716                                              &indio_dev->dev,
 717                                              &indio_dev->channel_attr_list);
 718                 if (ret == -EBUSY) {
 719                         ret = 0;
 720                         continue;
 721                 } else if (ret < 0) {
 722                         goto error_ret;
 723                 }
 724                 attrcount++;
 725         }
 726
 727         if (chan->ext_info) {
 728                 unsigned int i = 0;
 729                 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
 730                         ret = __iio_add_chan_devattr(ext_info->name,
 731                                         chan,
 732                                         ext_info->read ?
 733                                             &iio_read_channel_ext_info : NULL,
 734                                         ext_info->write ?
 735                                             &iio_write_channel_ext_info : NULL,
 736                                         i,
 737                                         ext_info->shared,
 738                                         &indio_dev->dev,
 739                                         &indio_dev->channel_attr_list);
 740                         i++;
 741                         if (ret == -EBUSY && ext_info->shared)
 742                                 continue;
 743
 744                         if (ret)
 745                                 goto error_ret;
 746
 747                         attrcount++;
 748                 }
 749         }
 750
 751         ret = attrcount;
 752 error_ret:
 753         return ret;
 754 }
 755
 756 static void iio_device_remove_and_free_read_attr(struct iio_dev *indio_dev,
 757                                                  struct iio_dev_attr *p)
 758 {
 759         kfree(p->dev_attr.attr.name);
 760         kfree(p);
 761 }
 762
 763 static ssize_t iio_show_dev_name(struct device *dev,
 764                                  struct device_attribute *attr,
 765                                  char *buf)
 766 {
 767         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 768         return sprintf(buf, "%s\n", indio_dev->name);
 769 }
 770
 771 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
 772
 773 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
 774 {
 775         int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
 776         struct iio_dev_attr *p, *n;
 777         struct attribute **attr;
 778
 779         /* First count elements in any existing group */
 780         if (indio_dev->info->attrs) {
 781                 attr = indio_dev->info->attrs->attrs;
 782                 while (*attr++ != NULL)
 783                         attrcount_orig++;
 784         }
 785         attrcount = attrcount_orig;
 786         /*
 787          * New channel registration method - relies on the fact a group does
 788          * not need to be initialized if its name is NULL.
 789          */
 790         if (indio_dev->channels)
 791                 for (i = 0; i < indio_dev->num_channels; i++) {
 792                         ret = iio_device_add_channel_sysfs(indio_dev,
 793                                                            &indio_dev
 794                                                            ->channels[i]);
 795                         if (ret < 0)
 796                                 goto error_clear_attrs;
 797                         attrcount += ret;
 798                 }
 799
 800         if (indio_dev->name)
 801                 attrcount++;
 802
 803         indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
 804                                                    sizeof(indio_dev->chan_attr_group.attrs[0]),
 805                                                    GFP_KERNEL);
 806         if (indio_dev->chan_attr_group.attrs == NULL) {
 807                 ret = -ENOMEM;
 808                 goto error_clear_attrs;
 809         }
 810         /* Copy across original attributes */
 811         if (indio_dev->info->attrs)
 812                 memcpy(indio_dev->chan_attr_group.attrs,
 813                        indio_dev->info->attrs->attrs,
 814                        sizeof(indio_dev->chan_attr_group.attrs[0])
 815                        *attrcount_orig);
 816         attrn = attrcount_orig;
 817         /* Add all elements from the list. */
 818         list_for_each_entry(p, &indio_dev->channel_attr_list, l)
 819                 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
 820         if (indio_dev->name)
 821                 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
 822
 823         indio_dev->groups[indio_dev->groupcounter++] =
 824                 &indio_dev->chan_attr_group;
 825
 826         return 0;
 827
 828 error_clear_attrs:
 829         list_for_each_entry_safe(p, n,
 830                                  &indio_dev->channel_attr_list, l) {
 831                 list_del(&p->l);
 832                 iio_device_remove_and_free_read_attr(indio_dev, p);
 833         }
 834
 835         return ret;
 836 }
 837
 838 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
 839 {
 840
 841         struct iio_dev_attr *p, *n;
 842
 843         list_for_each_entry_safe(p, n, &indio_dev->channel_attr_list, l) {
 844                 list_del(&p->l);
 845                 iio_device_remove_and_free_read_attr(indio_dev, p);
 846         }
 847         kfree(indio_dev->chan_attr_group.attrs);
 848 }
 849
 850 static void iio_dev_release(struct device *device)
 851 {
 852         struct iio_dev *indio_dev = dev_to_iio_dev(device);
 853         if (indio_dev->chrdev.dev)
 854                 cdev_del(&indio_dev->chrdev);
 855         if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
 856                 iio_device_unregister_trigger_consumer(indio_dev);
 857         iio_device_unregister_eventset(indio_dev);
 858         iio_device_unregister_sysfs(indio_dev);
 859         iio_device_unregister_debugfs(indio_dev);
 860
 861         ida_simple_remove(&iio_ida, indio_dev->id);
 862         kfree(indio_dev);
 863 }
 864
 865 struct device_type iio_device_type = {
 866         .name = "iio_device",
 867         .release = iio_dev_release,
 868 };
 869
 870 struct iio_dev *iio_device_alloc(int sizeof_priv)
 871 {
 872         struct iio_dev *dev;
 873         size_t alloc_size;
 874
 875         alloc_size = sizeof(struct iio_dev);
 876         if (sizeof_priv) {
 877                 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
 878                 alloc_size += sizeof_priv;
 879         }
 880         /* ensure 32-byte alignment of whole construct ? */
 881         alloc_size += IIO_ALIGN - 1;
 882
 883         dev = kzalloc(alloc_size, GFP_KERNEL);
 884
 885         if (dev) {
 886                 dev->dev.groups = dev->groups;
 887                 dev->dev.type = &iio_device_type;
 888                 dev->dev.bus = &iio_bus_type;
 889                 device_initialize(&dev->dev);
 890                 dev_set_drvdata(&dev->dev, (void *)dev);
 891                 mutex_init(&dev->mlock);
 892                 mutex_init(&dev->info_exist_lock);
 893                 INIT_LIST_HEAD(&dev->channel_attr_list);
 894
 895                 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
 896                 if (dev->id < 0) {
 897                         /* cannot use a dev_err as the name isn't available */
 898                         printk(KERN_ERR "Failed to get id\n");
 899                         kfree(dev);
 900                         return NULL;
 901                 }
 902                 dev_set_name(&dev->dev, "iio:device%d", dev->id);
 903                 INIT_LIST_HEAD(&dev->buffer_list);
 904         }
 905
 906         return dev;
 907 }
 908 EXPORT_SYMBOL(iio_device_alloc);
 909
 910 void iio_device_free(struct iio_dev *dev)
 911 {
 912         if (dev)
 913                 put_device(&dev->dev);
 914 }
 915 EXPORT_SYMBOL(iio_device_free);
 916
 917 /**
 918  * iio_chrdev_open() - chrdev file open for buffer access and ioctls
 919  **/
 920 static int iio_chrdev_open(struct inode *inode, struct file *filp)
 921 {
 922         struct iio_dev *indio_dev = container_of(inode->i_cdev,
 923                                                 struct iio_dev, chrdev);
 924
 925         if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
 926                 return -EBUSY;
 927
 928         filp->private_data = indio_dev;
 929
 930         return 0;
 931 }
 932
 933 /**
 934  * iio_chrdev_release() - chrdev file close buffer access and ioctls
 935  **/
 936 static int iio_chrdev_release(struct inode *inode, struct file *filp)
 937 {
 938         struct iio_dev *indio_dev = container_of(inode->i_cdev,
 939                                                 struct iio_dev, chrdev);
 940         clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
 941         return 0;
 942 }
 943
 944 /* Somewhat of a cross file organization violation - ioctls here are actually
 945  * event related */
 946 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 947 {
 948         struct iio_dev *indio_dev = filp->private_data;
 949         int __user *ip = (int __user *)arg;
 950         int fd;
 951
 952         if (cmd == IIO_GET_EVENT_FD_IOCTL) {
 953                 fd = iio_event_getfd(indio_dev);
 954                 if (copy_to_user(ip, &fd, sizeof(fd)))
 955                         return -EFAULT;
 956                 return 0;
 957         }
 958         return -EINVAL;
 959 }
 960
 961 static const struct file_operations iio_buffer_fileops = {
 962         .read = iio_buffer_read_first_n_outer_addr,
 963         .release = iio_chrdev_release,
 964         .open = iio_chrdev_open,
 965         .poll = iio_buffer_poll_addr,
 966         .owner = THIS_MODULE,
 967         .llseek = noop_llseek,
 968         .unlocked_ioctl = iio_ioctl,
 969         .compat_ioctl = iio_ioctl,
 970 };
 971
 972 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
 973
 974 int iio_device_register(struct iio_dev *indio_dev)
 975 {
 976         int ret;
 977
 978         /* If the calling driver did not initialize of_node, do it here */
 979         if (!indio_dev->dev.of_node && indio_dev->dev.parent)
 980                 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
 981
 982         /* configure elements for the chrdev */
 983         indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
 984
 985         ret = iio_device_register_debugfs(indio_dev);
 986         if (ret) {
 987                 dev_err(indio_dev->dev.parent,
 988                         "Failed to register debugfs interfaces\n");
 989                 goto error_ret;
 990         }
 991         ret = iio_device_register_sysfs(indio_dev);
 992         if (ret) {
 993                 dev_err(indio_dev->dev.parent,
 994                         "Failed to register sysfs interfaces\n");
 995                 goto error_unreg_debugfs;
 996         }
 997         ret = iio_device_register_eventset(indio_dev);
 998         if (ret) {
 999                 dev_err(indio_dev->dev.parent,
1000                         "Failed to register event set\n");
1001                 goto error_free_sysfs;
1002         }
1003         if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
1004                 iio_device_register_trigger_consumer(indio_dev);
1005
1006         if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1007                 indio_dev->setup_ops == NULL)
1008                 indio_dev->setup_ops = &noop_ring_setup_ops;
1009
1010         ret = device_add(&indio_dev->dev);
1011         if (ret < 0)
1012                 goto error_unreg_eventset;
1013         cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1014         indio_dev->chrdev.owner = indio_dev->info->driver_module;
1015         ret = cdev_add(&indio_dev->chrdev, indio_dev->dev.devt, 1);
1016         if (ret < 0)
1017                 goto error_del_device;
1018         return 0;
1019
1020 error_del_device:
1021         device_del(&indio_dev->dev);
1022 error_unreg_eventset:
1023         iio_device_unregister_eventset(indio_dev);
1024 error_free_sysfs:
1025         iio_device_unregister_sysfs(indio_dev);
1026 error_unreg_debugfs:
1027         iio_device_unregister_debugfs(indio_dev);
1028 error_ret:
1029         return ret;
1030 }
1031 EXPORT_SYMBOL(iio_device_register);
1032
1033 void iio_device_unregister(struct iio_dev *indio_dev)
1034 {
1035         mutex_lock(&indio_dev->info_exist_lock);
1036         indio_dev->info = NULL;
1037         mutex_unlock(&indio_dev->info_exist_lock);
1038         device_del(&indio_dev->dev);
1039 }
1040 EXPORT_SYMBOL(iio_device_unregister);
1041 subsys_initcall(iio_init);
1042 module_exit(iio_exit);
1043
1044 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1045 MODULE_DESCRIPTION("Industrial I/O core");
1046 MODULE_LICENSE("GPL");