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