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 #define pr_fmt(fmt) "iio-core: " fmt
  13
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/idr.h>
  17 #include <linux/kdev_t.h>
  18 #include <linux/err.h>
  19 #include <linux/device.h>
  20 #include <linux/fs.h>
  21 #include <linux/poll.h>
  22 #include <linux/sched.h>
  23 #include <linux/wait.h>
  24 #include <linux/cdev.h>
  25 #include <linux/slab.h>
  26 #include <linux/anon_inodes.h>
  27 #include <linux/debugfs.h>
  28 #include <linux/mutex.h>
  29 #include <linux/iio/iio.h>
  30 #include "iio_core.h"
  31 #include "iio_core_trigger.h"
  32 #include <linux/iio/sysfs.h>
  33 #include <linux/iio/events.h>
  34 #include <linux/iio/buffer.h>
  35 #include <linux/iio/buffer_impl.h>
  36
  37 /* IDA to assign each registered device a unique id */
  38 static DEFINE_IDA(iio_ida);
  39
  40 static dev_t iio_devt;
  41
  42 #define IIO_DEV_MAX 256
  43 struct bus_type iio_bus_type = {
  44         .name = "iio",
  45 };
  46 EXPORT_SYMBOL(iio_bus_type);
  47
  48 static struct dentry *iio_debugfs_dentry;
  49
  50 static const char * const iio_direction[] = {
  51         [0] = "in",
  52         [1] = "out",
  53 };
  54
  55 static const char * const iio_chan_type_name_spec[] = {
  56         [IIO_VOLTAGE] = "voltage",
  57         [IIO_CURRENT] = "current",
  58         [IIO_POWER] = "power",
  59         [IIO_ACCEL] = "accel",
  60         [IIO_ANGL_VEL] = "anglvel",
  61         [IIO_MAGN] = "magn",
  62         [IIO_LIGHT] = "illuminance",
  63         [IIO_INTENSITY] = "intensity",
  64         [IIO_PROXIMITY] = "proximity",
  65         [IIO_TEMP] = "temp",
  66         [IIO_INCLI] = "incli",
  67         [IIO_ROT] = "rot",
  68         [IIO_ANGL] = "angl",
  69         [IIO_TIMESTAMP] = "timestamp",
  70         [IIO_CAPACITANCE] = "capacitance",
  71         [IIO_ALTVOLTAGE] = "altvoltage",
  72         [IIO_CCT] = "cct",
  73         [IIO_PRESSURE] = "pressure",
  74         [IIO_HUMIDITYRELATIVE] = "humidityrelative",
  75         [IIO_ACTIVITY] = "activity",
  76         [IIO_STEPS] = "steps",
  77         [IIO_ENERGY] = "energy",
  78         [IIO_DISTANCE] = "distance",
  79         [IIO_VELOCITY] = "velocity",
  80         [IIO_CONCENTRATION] = "concentration",
  81         [IIO_RESISTANCE] = "resistance",
  82         [IIO_PH] = "ph",
  83         [IIO_UVINDEX] = "uvindex",
  84         [IIO_ELECTRICALCONDUCTIVITY] = "electricalconductivity",
  85         [IIO_COUNT] = "count",
  86         [IIO_INDEX] = "index",
  87         [IIO_GRAVITY]  = "gravity",
  88         [IIO_POSITIONRELATIVE]  = "positionrelative",
  89         [IIO_PHASE] = "phase",
  90 };
  91
  92 static const char * const iio_modifier_names[] = {
  93         [IIO_MOD_X] = "x",
  94         [IIO_MOD_Y] = "y",
  95         [IIO_MOD_Z] = "z",
  96         [IIO_MOD_X_AND_Y] = "x&y",
  97         [IIO_MOD_X_AND_Z] = "x&z",
  98         [IIO_MOD_Y_AND_Z] = "y&z",
  99         [IIO_MOD_X_AND_Y_AND_Z] = "x&y&z",
 100         [IIO_MOD_X_OR_Y] = "x|y",
 101         [IIO_MOD_X_OR_Z] = "x|z",
 102         [IIO_MOD_Y_OR_Z] = "y|z",
 103         [IIO_MOD_X_OR_Y_OR_Z] = "x|y|z",
 104         [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
 105         [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
 106         [IIO_MOD_LIGHT_BOTH] = "both",
 107         [IIO_MOD_LIGHT_IR] = "ir",
 108         [IIO_MOD_LIGHT_CLEAR] = "clear",
 109         [IIO_MOD_LIGHT_RED] = "red",
 110         [IIO_MOD_LIGHT_GREEN] = "green",
 111         [IIO_MOD_LIGHT_BLUE] = "blue",
 112         [IIO_MOD_LIGHT_UV] = "uv",
 113         [IIO_MOD_LIGHT_DUV] = "duv",
 114         [IIO_MOD_QUATERNION] = "quaternion",
 115         [IIO_MOD_TEMP_AMBIENT] = "ambient",
 116         [IIO_MOD_TEMP_OBJECT] = "object",
 117         [IIO_MOD_NORTH_MAGN] = "from_north_magnetic",
 118         [IIO_MOD_NORTH_TRUE] = "from_north_true",
 119         [IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",
 120         [IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",
 121         [IIO_MOD_RUNNING] = "running",
 122         [IIO_MOD_JOGGING] = "jogging",
 123         [IIO_MOD_WALKING] = "walking",
 124         [IIO_MOD_STILL] = "still",
 125         [IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",
 126         [IIO_MOD_I] = "i",
 127         [IIO_MOD_Q] = "q",
 128         [IIO_MOD_CO2] = "co2",
 129         [IIO_MOD_VOC] = "voc",
 130 };
 131
 132 /* relies on pairs of these shared then separate */
 133 static const char * const iio_chan_info_postfix[] = {
 134         [IIO_CHAN_INFO_RAW] = "raw",
 135         [IIO_CHAN_INFO_PROCESSED] = "input",
 136         [IIO_CHAN_INFO_SCALE] = "scale",
 137         [IIO_CHAN_INFO_OFFSET] = "offset",
 138         [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
 139         [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
 140         [IIO_CHAN_INFO_PEAK] = "peak_raw",
 141         [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
 142         [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
 143         [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
 144         [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
 145         = "filter_low_pass_3db_frequency",
 146         [IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY]
 147         = "filter_high_pass_3db_frequency",
 148         [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
 149         [IIO_CHAN_INFO_FREQUENCY] = "frequency",
 150         [IIO_CHAN_INFO_PHASE] = "phase",
 151         [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
 152         [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
 153         [IIO_CHAN_INFO_INT_TIME] = "integration_time",
 154         [IIO_CHAN_INFO_ENABLE] = "en",
 155         [IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
 156         [IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",
 157         [IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count",
 158         [IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time",
 159         [IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity",
 160         [IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio",
 161 };
 162
 163 /**
 164  * iio_find_channel_from_si() - get channel from its scan index
 165  * @indio_dev:          device
 166  * @si:                 scan index to match
 167  */
 168 const struct iio_chan_spec
 169 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
 170 {
 171         int i;
 172
 173         for (i = 0; i < indio_dev->num_channels; i++)
 174                 if (indio_dev->channels[i].scan_index == si)
 175                         return &indio_dev->channels[i];
 176         return NULL;
 177 }
 178
 179 /* This turns up an awful lot */
 180 ssize_t iio_read_const_attr(struct device *dev,
 181                             struct device_attribute *attr,
 182                             char *buf)
 183 {
 184         return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
 185 }
 186 EXPORT_SYMBOL(iio_read_const_attr);
 187
 188 static int iio_device_set_clock(struct iio_dev *indio_dev, clockid_t clock_id)
 189 {
 190         int ret;
 191         const struct iio_event_interface *ev_int = indio_dev->event_interface;
 192
 193         ret = mutex_lock_interruptible(&indio_dev->mlock);
 194         if (ret)
 195                 return ret;
 196         if ((ev_int && iio_event_enabled(ev_int)) ||
 197             iio_buffer_enabled(indio_dev)) {
 198                 mutex_unlock(&indio_dev->mlock);
 199                 return -EBUSY;
 200         }
 201         indio_dev->clock_id = clock_id;
 202         mutex_unlock(&indio_dev->mlock);
 203
 204         return 0;
 205 }
 206
 207 /**
 208  * iio_get_time_ns() - utility function to get a time stamp for events etc
 209  * @indio_dev: device
 210  */
 211 s64 iio_get_time_ns(const struct iio_dev *indio_dev)
 212 {
 213         struct timespec64 tp;
 214
 215         switch (iio_device_get_clock(indio_dev)) {
 216         case CLOCK_REALTIME:
 217                 return ktime_get_real_ns();
 218         case CLOCK_MONOTONIC:
 219                 return ktime_get_ns();
 220         case CLOCK_MONOTONIC_RAW:
 221                 return ktime_get_raw_ns();
 222         case CLOCK_REALTIME_COARSE:
 223                 return ktime_to_ns(ktime_get_coarse_real());
 224         case CLOCK_MONOTONIC_COARSE:
 225                 ktime_get_coarse_ts64(&tp);
 226                 return timespec64_to_ns(&tp);
 227         case CLOCK_BOOTTIME:
 228                 return ktime_get_boot_ns();
 229         case CLOCK_TAI:
 230                 return ktime_get_tai_ns();
 231         default:
 232                 BUG();
 233         }
 234 }
 235 EXPORT_SYMBOL(iio_get_time_ns);
 236
 237 /**
 238  * iio_get_time_res() - utility function to get time stamp clock resolution in
 239  *                      nano seconds.
 240  * @indio_dev: device
 241  */
 242 unsigned int iio_get_time_res(const struct iio_dev *indio_dev)
 243 {
 244         switch (iio_device_get_clock(indio_dev)) {
 245         case CLOCK_REALTIME:
 246         case CLOCK_MONOTONIC:
 247         case CLOCK_MONOTONIC_RAW:
 248         case CLOCK_BOOTTIME:
 249         case CLOCK_TAI:
 250                 return hrtimer_resolution;
 251         case CLOCK_REALTIME_COARSE:
 252         case CLOCK_MONOTONIC_COARSE:
 253                 return LOW_RES_NSEC;
 254         default:
 255                 BUG();
 256         }
 257 }
 258 EXPORT_SYMBOL(iio_get_time_res);
 259
 260 static int __init iio_init(void)
 261 {
 262         int ret;
 263
 264         /* Register sysfs bus */
 265         ret  = bus_register(&iio_bus_type);
 266         if (ret < 0) {
 267                 pr_err("could not register bus type\n");
 268                 goto error_nothing;
 269         }
 270
 271         ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
 272         if (ret < 0) {
 273                 pr_err("failed to allocate char dev region\n");
 274                 goto error_unregister_bus_type;
 275         }
 276
 277         iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
 278
 279         return 0;
 280
 281 error_unregister_bus_type:
 282         bus_unregister(&iio_bus_type);
 283 error_nothing:
 284         return ret;
 285 }
 286
 287 static void __exit iio_exit(void)
 288 {
 289         if (iio_devt)
 290                 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
 291         bus_unregister(&iio_bus_type);
 292         debugfs_remove(iio_debugfs_dentry);
 293 }
 294
 295 #if defined(CONFIG_DEBUG_FS)
 296 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
 297                               size_t count, loff_t *ppos)
 298 {
 299         struct iio_dev *indio_dev = file->private_data;
 300         char buf[20];
 301         unsigned val = 0;
 302         ssize_t len;
 303         int ret;
 304
 305         ret = indio_dev->info->debugfs_reg_access(indio_dev,
 306                                                   indio_dev->cached_reg_addr,
 307                                                   0, &val);
 308         if (ret) {
 309                 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
 310                 return ret;
 311         }
 312
 313         len = snprintf(buf, sizeof(buf), "0x%X\n", val);
 314
 315         return simple_read_from_buffer(userbuf, count, ppos, buf, len);
 316 }
 317
 318 static ssize_t iio_debugfs_write_reg(struct file *file,
 319                      const char __user *userbuf, size_t count, loff_t *ppos)
 320 {
 321         struct iio_dev *indio_dev = file->private_data;
 322         unsigned reg, val;
 323         char buf[80];
 324         int ret;
 325
 326         count = min_t(size_t, count, (sizeof(buf)-1));
 327         if (copy_from_user(buf, userbuf, count))
 328                 return -EFAULT;
 329
 330         buf[count] = 0;
 331
 332         ret = sscanf(buf, "%i %i", &reg, &val);
 333
 334         switch (ret) {
 335         case 1:
 336                 indio_dev->cached_reg_addr = reg;
 337                 break;
 338         case 2:
 339                 indio_dev->cached_reg_addr = reg;
 340                 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
 341                                                           val, NULL);
 342                 if (ret) {
 343                         dev_err(indio_dev->dev.parent, "%s: write failed\n",
 344                                 __func__);
 345                         return ret;
 346                 }
 347                 break;
 348         default:
 349                 return -EINVAL;
 350         }
 351
 352         return count;
 353 }
 354
 355 static const struct file_operations iio_debugfs_reg_fops = {
 356         .open = simple_open,
 357         .read = iio_debugfs_read_reg,
 358         .write = iio_debugfs_write_reg,
 359 };
 360
 361 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
 362 {
 363         debugfs_remove_recursive(indio_dev->debugfs_dentry);
 364 }
 365
 366 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
 367 {
 368         struct dentry *d;
 369
 370         if (indio_dev->info->debugfs_reg_access == NULL)
 371                 return 0;
 372
 373         if (!iio_debugfs_dentry)
 374                 return 0;
 375
 376         indio_dev->debugfs_dentry =
 377                 debugfs_create_dir(dev_name(&indio_dev->dev),
 378                                    iio_debugfs_dentry);
 379         if (indio_dev->debugfs_dentry == NULL) {
 380                 dev_warn(indio_dev->dev.parent,
 381                          "Failed to create debugfs directory\n");
 382                 return -EFAULT;
 383         }
 384
 385         d = debugfs_create_file("direct_reg_access", 0644,
 386                                 indio_dev->debugfs_dentry,
 387                                 indio_dev, &iio_debugfs_reg_fops);
 388         if (!d) {
 389                 iio_device_unregister_debugfs(indio_dev);
 390                 return -ENOMEM;
 391         }
 392
 393         return 0;
 394 }
 395 #else
 396 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
 397 {
 398         return 0;
 399 }
 400
 401 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
 402 {
 403 }
 404 #endif /* CONFIG_DEBUG_FS */
 405
 406 static ssize_t iio_read_channel_ext_info(struct device *dev,
 407                                      struct device_attribute *attr,
 408                                      char *buf)
 409 {
 410         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 411         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 412         const struct iio_chan_spec_ext_info *ext_info;
 413
 414         ext_info = &this_attr->c->ext_info[this_attr->address];
 415
 416         return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
 417 }
 418
 419 static ssize_t iio_write_channel_ext_info(struct device *dev,
 420                                      struct device_attribute *attr,
 421                                      const char *buf,
 422                                          size_t len)
 423 {
 424         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 425         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 426         const struct iio_chan_spec_ext_info *ext_info;
 427
 428         ext_info = &this_attr->c->ext_info[this_attr->address];
 429
 430         return ext_info->write(indio_dev, ext_info->private,
 431                                this_attr->c, buf, len);
 432 }
 433
 434 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
 435         uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
 436 {
 437         const struct iio_enum *e = (const struct iio_enum *)priv;
 438         unsigned int i;
 439         size_t len = 0;
 440
 441         if (!e->num_items)
 442                 return 0;
 443
 444         for (i = 0; i < e->num_items; ++i)
 445                 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
 446
 447         /* replace last space with a newline */
 448         buf[len - 1] = '\n';
 449
 450         return len;
 451 }
 452 EXPORT_SYMBOL_GPL(iio_enum_available_read);
 453
 454 ssize_t iio_enum_read(struct iio_dev *indio_dev,
 455         uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
 456 {
 457         const struct iio_enum *e = (const struct iio_enum *)priv;
 458         int i;
 459
 460         if (!e->get)
 461                 return -EINVAL;
 462
 463         i = e->get(indio_dev, chan);
 464         if (i < 0)
 465                 return i;
 466         else if (i >= e->num_items)
 467                 return -EINVAL;
 468
 469         return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
 470 }
 471 EXPORT_SYMBOL_GPL(iio_enum_read);
 472
 473 ssize_t iio_enum_write(struct iio_dev *indio_dev,
 474         uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
 475         size_t len)
 476 {
 477         const struct iio_enum *e = (const struct iio_enum *)priv;
 478         int ret;
 479
 480         if (!e->set)
 481                 return -EINVAL;
 482
 483         ret = __sysfs_match_string(e->items, e->num_items, buf);
 484         if (ret < 0)
 485                 return ret;
 486
 487         ret = e->set(indio_dev, chan, ret);
 488         return ret ? ret : len;
 489 }
 490 EXPORT_SYMBOL_GPL(iio_enum_write);
 491
 492 static const struct iio_mount_matrix iio_mount_idmatrix = {
 493         .rotation = {
 494                 "1", "0", "0",
 495                 "0", "1", "0",
 496                 "0", "0", "1"
 497         }
 498 };
 499
 500 static int iio_setup_mount_idmatrix(const struct device *dev,
 501                                     struct iio_mount_matrix *matrix)
 502 {
 503         *matrix = iio_mount_idmatrix;
 504         dev_info(dev, "mounting matrix not found: using identity...\n");
 505         return 0;
 506 }
 507
 508 ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
 509                               const struct iio_chan_spec *chan, char *buf)
 510 {
 511         const struct iio_mount_matrix *mtx = ((iio_get_mount_matrix_t *)
 512                                               priv)(indio_dev, chan);
 513
 514         if (IS_ERR(mtx))
 515                 return PTR_ERR(mtx);
 516
 517         if (!mtx)
 518                 mtx = &iio_mount_idmatrix;
 519
 520         return snprintf(buf, PAGE_SIZE, "%s, %s, %s; %s, %s, %s; %s, %s, %s\n",
 521                         mtx->rotation[0], mtx->rotation[1], mtx->rotation[2],
 522                         mtx->rotation[3], mtx->rotation[4], mtx->rotation[5],
 523                         mtx->rotation[6], mtx->rotation[7], mtx->rotation[8]);
 524 }
 525 EXPORT_SYMBOL_GPL(iio_show_mount_matrix);
 526
 527 /**
 528  * of_iio_read_mount_matrix() - retrieve iio device mounting matrix from
 529  *                              device-tree "mount-matrix" property
 530  * @dev:        device the mounting matrix property is assigned to
 531  * @propname:   device specific mounting matrix property name
 532  * @matrix:     where to store retrieved matrix
 533  *
 534  * If device is assigned no mounting matrix property, a default 3x3 identity
 535  * matrix will be filled in.
 536  *
 537  * Return: 0 if success, or a negative error code on failure.
 538  */
 539 #ifdef CONFIG_OF
 540 int of_iio_read_mount_matrix(const struct device *dev,
 541                              const char *propname,
 542                              struct iio_mount_matrix *matrix)
 543 {
 544         if (dev->of_node) {
 545                 int err = of_property_read_string_array(dev->of_node,
 546                                 propname, matrix->rotation,
 547                                 ARRAY_SIZE(iio_mount_idmatrix.rotation));
 548
 549                 if (err == ARRAY_SIZE(iio_mount_idmatrix.rotation))
 550                         return 0;
 551
 552                 if (err >= 0)
 553                         /* Invalid number of matrix entries. */
 554                         return -EINVAL;
 555
 556                 if (err != -EINVAL)
 557                         /* Invalid matrix declaration format. */
 558                         return err;
 559         }
 560
 561         /* Matrix was not declared at all: fallback to identity. */
 562         return iio_setup_mount_idmatrix(dev, matrix);
 563 }
 564 #else
 565 int of_iio_read_mount_matrix(const struct device *dev,
 566                              const char *propname,
 567                              struct iio_mount_matrix *matrix)
 568 {
 569         return iio_setup_mount_idmatrix(dev, matrix);
 570 }
 571 #endif
 572 EXPORT_SYMBOL(of_iio_read_mount_matrix);
 573
 574 static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
 575                                   int size, const int *vals)
 576 {
 577         unsigned long long tmp;
 578         int tmp0, tmp1;
 579         bool scale_db = false;
 580
 581         switch (type) {
 582         case IIO_VAL_INT:
 583                 return snprintf(buf, len, "%d", vals[0]);
 584         case IIO_VAL_INT_PLUS_MICRO_DB:
 585                 scale_db = true;
 586                 /* fall through */
 587         case IIO_VAL_INT_PLUS_MICRO:
 588                 if (vals[1] < 0)
 589                         return snprintf(buf, len, "-%d.%06u%s", abs(vals[0]),
 590                                         -vals[1], scale_db ? " dB" : "");
 591                 else
 592                         return snprintf(buf, len, "%d.%06u%s", vals[0], vals[1],
 593                                         scale_db ? " dB" : "");
 594         case IIO_VAL_INT_PLUS_NANO:
 595                 if (vals[1] < 0)
 596                         return snprintf(buf, len, "-%d.%09u", abs(vals[0]),
 597                                         -vals[1]);
 598                 else
 599                         return snprintf(buf, len, "%d.%09u", vals[0], vals[1]);
 600         case IIO_VAL_FRACTIONAL:
 601                 tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
 602                 tmp1 = vals[1];
 603                 tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1);
 604                 return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
 605         case IIO_VAL_FRACTIONAL_LOG2:
 606                 tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]);
 607                 tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1);
 608                 return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
 609         case IIO_VAL_INT_MULTIPLE:
 610         {
 611                 int i;
 612                 int l = 0;
 613
 614                 for (i = 0; i < size; ++i) {
 615                         l += snprintf(&buf[l], len - l, "%d ", vals[i]);
 616                         if (l >= len)
 617                                 break;
 618                 }
 619                 return l;
 620         }
 621         default:
 622                 return 0;
 623         }
 624 }
 625
 626 /**
 627  * iio_format_value() - Formats a IIO value into its string representation
 628  * @buf:        The buffer to which the formatted value gets written
 629  *              which is assumed to be big enough (i.e. PAGE_SIZE).
 630  * @type:       One of the IIO_VAL_* constants. This decides how the val
 631  *              and val2 parameters are formatted.
 632  * @size:       Number of IIO value entries contained in vals
 633  * @vals:       Pointer to the values, exact meaning depends on the
 634  *              type parameter.
 635  *
 636  * Return: 0 by default, a negative number on failure or the
 637  *         total number of characters written for a type that belongs
 638  *         to the IIO_VAL_* constant.
 639  */
 640 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
 641 {
 642         ssize_t len;
 643
 644         len = __iio_format_value(buf, PAGE_SIZE, type, size, vals);
 645         if (len >= PAGE_SIZE - 1)
 646                 return -EFBIG;
 647
 648         return len + sprintf(buf + len, "\n");
 649 }
 650 EXPORT_SYMBOL_GPL(iio_format_value);
 651
 652 static ssize_t iio_read_channel_info(struct device *dev,
 653                                      struct device_attribute *attr,
 654                                      char *buf)
 655 {
 656         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 657         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 658         int vals[INDIO_MAX_RAW_ELEMENTS];
 659         int ret;
 660         int val_len = 2;
 661
 662         if (indio_dev->info->read_raw_multi)
 663                 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
 664                                                         INDIO_MAX_RAW_ELEMENTS,
 665                                                         vals, &val_len,
 666                                                         this_attr->address);
 667         else
 668                 ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
 669                                     &vals[0], &vals[1], this_attr->address);
 670
 671         if (ret < 0)
 672                 return ret;
 673
 674         return iio_format_value(buf, ret, val_len, vals);
 675 }
 676
 677 static ssize_t iio_format_avail_list(char *buf, const int *vals,
 678                                      int type, int length)
 679 {
 680         int i;
 681         ssize_t len = 0;
 682
 683         switch (type) {
 684         case IIO_VAL_INT:
 685                 for (i = 0; i < length; i++) {
 686                         len += __iio_format_value(buf + len, PAGE_SIZE - len,
 687                                                   type, 1, &vals[i]);
 688                         if (len >= PAGE_SIZE)
 689                                 return -EFBIG;
 690                         if (i < length - 1)
 691                                 len += snprintf(buf + len, PAGE_SIZE - len,
 692                                                 " ");
 693                         else
 694                                 len += snprintf(buf + len, PAGE_SIZE - len,
 695                                                 "\n");
 696                         if (len >= PAGE_SIZE)
 697                                 return -EFBIG;
 698                 }
 699                 break;
 700         default:
 701                 for (i = 0; i < length / 2; i++) {
 702                         len += __iio_format_value(buf + len, PAGE_SIZE - len,
 703                                                   type, 2, &vals[i * 2]);
 704                         if (len >= PAGE_SIZE)
 705                                 return -EFBIG;
 706                         if (i < length / 2 - 1)
 707                                 len += snprintf(buf + len, PAGE_SIZE - len,
 708                                                 " ");
 709                         else
 710                                 len += snprintf(buf + len, PAGE_SIZE - len,
 711                                                 "\n");
 712                         if (len >= PAGE_SIZE)
 713                                 return -EFBIG;
 714                 }
 715         }
 716
 717         return len;
 718 }
 719
 720 static ssize_t iio_format_avail_range(char *buf, const int *vals, int type)
 721 {
 722         int i;
 723         ssize_t len;
 724
 725         len = snprintf(buf, PAGE_SIZE, "[");
 726         switch (type) {
 727         case IIO_VAL_INT:
 728                 for (i = 0; i < 3; i++) {
 729                         len += __iio_format_value(buf + len, PAGE_SIZE - len,
 730                                                   type, 1, &vals[i]);
 731                         if (len >= PAGE_SIZE)
 732                                 return -EFBIG;
 733                         if (i < 2)
 734                                 len += snprintf(buf + len, PAGE_SIZE - len,
 735                                                 " ");
 736                         else
 737                                 len += snprintf(buf + len, PAGE_SIZE - len,
 738                                                 "]\n");
 739                         if (len >= PAGE_SIZE)
 740                                 return -EFBIG;
 741                 }
 742                 break;
 743         default:
 744                 for (i = 0; i < 3; i++) {
 745                         len += __iio_format_value(buf + len, PAGE_SIZE - len,
 746                                                   type, 2, &vals[i * 2]);
 747                         if (len >= PAGE_SIZE)
 748                                 return -EFBIG;
 749                         if (i < 2)
 750                                 len += snprintf(buf + len, PAGE_SIZE - len,
 751                                                 " ");
 752                         else
 753                                 len += snprintf(buf + len, PAGE_SIZE - len,
 754                                                 "]\n");
 755                         if (len >= PAGE_SIZE)
 756                                 return -EFBIG;
 757                 }
 758         }
 759
 760         return len;
 761 }
 762
 763 static ssize_t iio_read_channel_info_avail(struct device *dev,
 764                                            struct device_attribute *attr,
 765                                            char *buf)
 766 {
 767         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 768         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 769         const int *vals;
 770         int ret;
 771         int length;
 772         int type;
 773
 774         ret = indio_dev->info->read_avail(indio_dev, this_attr->c,
 775                                           &vals, &type, &length,
 776                                           this_attr->address);
 777
 778         if (ret < 0)
 779                 return ret;
 780         switch (ret) {
 781         case IIO_AVAIL_LIST:
 782                 return iio_format_avail_list(buf, vals, type, length);
 783         case IIO_AVAIL_RANGE:
 784                 return iio_format_avail_range(buf, vals, type);
 785         default:
 786                 return -EINVAL;
 787         }
 788 }
 789
 790 /**
 791  * iio_str_to_fixpoint() - Parse a fixed-point number from a string
 792  * @str: The string to parse
 793  * @fract_mult: Multiplier for the first decimal place, should be a power of 10
 794  * @integer: The integer part of the number
 795  * @fract: The fractional part of the number
 796  *
 797  * Returns 0 on success, or a negative error code if the string could not be
 798  * parsed.
 799  */
 800 int iio_str_to_fixpoint(const char *str, int fract_mult,
 801         int *integer, int *fract)
 802 {
 803         int i = 0, f = 0;
 804         bool integer_part = true, negative = false;
 805
 806         if (fract_mult == 0) {
 807                 *fract = 0;
 808
 809                 return kstrtoint(str, 0, integer);
 810         }
 811
 812         if (str[0] == '-') {
 813                 negative = true;
 814                 str++;
 815         } else if (str[0] == '+') {
 816                 str++;
 817         }
 818
 819         while (*str) {
 820                 if ('0' <= *str && *str <= '9') {
 821                         if (integer_part) {
 822                                 i = i * 10 + *str - '0';
 823                         } else {
 824                                 f += fract_mult * (*str - '0');
 825                                 fract_mult /= 10;
 826                         }
 827                 } else if (*str == '\n') {
 828                         if (*(str + 1) == '\0')
 829                                 break;
 830                         else
 831                                 return -EINVAL;
 832                 } else if (*str == '.' && integer_part) {
 833                         integer_part = false;
 834                 } else {
 835                         return -EINVAL;
 836                 }
 837                 str++;
 838         }
 839
 840         if (negative) {
 841                 if (i)
 842                         i = -i;
 843                 else
 844                         f = -f;
 845         }
 846
 847         *integer = i;
 848         *fract = f;
 849
 850         return 0;
 851 }
 852 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
 853
 854 static ssize_t iio_write_channel_info(struct device *dev,
 855                                       struct device_attribute *attr,
 856                                       const char *buf,
 857                                       size_t len)
 858 {
 859         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 860         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 861         int ret, fract_mult = 100000;
 862         int integer, fract;
 863
 864         /* Assumes decimal - precision based on number of digits */
 865         if (!indio_dev->info->write_raw)
 866                 return -EINVAL;
 867
 868         if (indio_dev->info->write_raw_get_fmt)
 869                 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
 870                         this_attr->c, this_attr->address)) {
 871                 case IIO_VAL_INT:
 872                         fract_mult = 0;
 873                         break;
 874                 case IIO_VAL_INT_PLUS_MICRO:
 875                         fract_mult = 100000;
 876                         break;
 877                 case IIO_VAL_INT_PLUS_NANO:
 878                         fract_mult = 100000000;
 879                         break;
 880                 default:
 881                         return -EINVAL;
 882                 }
 883
 884         ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
 885         if (ret)
 886                 return ret;
 887
 888         ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
 889                                          integer, fract, this_attr->address);
 890         if (ret)
 891                 return ret;
 892
 893         return len;
 894 }
 895
 896 static
 897 int __iio_device_attr_init(struct device_attribute *dev_attr,
 898                            const char *postfix,
 899                            struct iio_chan_spec const *chan,
 900                            ssize_t (*readfunc)(struct device *dev,
 901                                                struct device_attribute *attr,
 902                                                char *buf),
 903                            ssize_t (*writefunc)(struct device *dev,
 904                                                 struct device_attribute *attr,
 905                                                 const char *buf,
 906                                                 size_t len),
 907                            enum iio_shared_by shared_by)
 908 {
 909         int ret = 0;
 910         char *name = NULL;
 911         char *full_postfix;
 912         sysfs_attr_init(&dev_attr->attr);
 913
 914         /* Build up postfix of <extend_name>_<modifier>_postfix */
 915         if (chan->modified && (shared_by == IIO_SEPARATE)) {
 916                 if (chan->extend_name)
 917                         full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
 918                                                  iio_modifier_names[chan
 919                                                                     ->channel2],
 920                                                  chan->extend_name,
 921                                                  postfix);
 922                 else
 923                         full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
 924                                                  iio_modifier_names[chan
 925                                                                     ->channel2],
 926                                                  postfix);
 927         } else {
 928                 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)
 929                         full_postfix = kstrdup(postfix, GFP_KERNEL);
 930                 else
 931                         full_postfix = kasprintf(GFP_KERNEL,
 932                                                  "%s_%s",
 933                                                  chan->extend_name,
 934                                                  postfix);
 935         }
 936         if (full_postfix == NULL)
 937                 return -ENOMEM;
 938
 939         if (chan->differential) { /* Differential can not have modifier */
 940                 switch (shared_by) {
 941                 case IIO_SHARED_BY_ALL:
 942                         name = kasprintf(GFP_KERNEL, "%s", full_postfix);
 943                         break;
 944                 case IIO_SHARED_BY_DIR:
 945                         name = kasprintf(GFP_KERNEL, "%s_%s",
 946                                                 iio_direction[chan->output],
 947                                                 full_postfix);
 948                         break;
 949                 case IIO_SHARED_BY_TYPE:
 950                         name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
 951                                             iio_direction[chan->output],
 952                                             iio_chan_type_name_spec[chan->type],
 953                                             iio_chan_type_name_spec[chan->type],
 954                                             full_postfix);
 955                         break;
 956                 case IIO_SEPARATE:
 957                         if (!chan->indexed) {
 958                                 WARN(1, "Differential channels must be indexed\n");
 959                                 ret = -EINVAL;
 960                                 goto error_free_full_postfix;
 961                         }
 962                         name = kasprintf(GFP_KERNEL,
 963                                             "%s_%s%d-%s%d_%s",
 964                                             iio_direction[chan->output],
 965                                             iio_chan_type_name_spec[chan->type],
 966                                             chan->channel,
 967                                             iio_chan_type_name_spec[chan->type],
 968                                             chan->channel2,
 969                                             full_postfix);
 970                         break;
 971                 }
 972         } else { /* Single ended */
 973                 switch (shared_by) {
 974                 case IIO_SHARED_BY_ALL:
 975                         name = kasprintf(GFP_KERNEL, "%s", full_postfix);
 976                         break;
 977                 case IIO_SHARED_BY_DIR:
 978                         name = kasprintf(GFP_KERNEL, "%s_%s",
 979                                                 iio_direction[chan->output],
 980                                                 full_postfix);
 981                         break;
 982                 case IIO_SHARED_BY_TYPE:
 983                         name = kasprintf(GFP_KERNEL, "%s_%s_%s",
 984                                             iio_direction[chan->output],
 985                                             iio_chan_type_name_spec[chan->type],
 986                                             full_postfix);
 987                         break;
 988
 989                 case IIO_SEPARATE:
 990                         if (chan->indexed)
 991                                 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
 992                                                     iio_direction[chan->output],
 993                                                     iio_chan_type_name_spec[chan->type],
 994                                                     chan->channel,
 995                                                     full_postfix);
 996                         else
 997                                 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
 998                                                     iio_direction[chan->output],
 999                                                     iio_chan_type_name_spec[chan->type],
1000                                                     full_postfix);
1001                         break;
1002                 }
1003         }
1004         if (name == NULL) {
1005                 ret = -ENOMEM;
1006                 goto error_free_full_postfix;
1007         }
1008         dev_attr->attr.name = name;
1009
1010         if (readfunc) {
1011                 dev_attr->attr.mode |= S_IRUGO;
1012                 dev_attr->show = readfunc;
1013         }
1014
1015         if (writefunc) {
1016                 dev_attr->attr.mode |= S_IWUSR;
1017                 dev_attr->store = writefunc;
1018         }
1019
1020 error_free_full_postfix:
1021         kfree(full_postfix);
1022
1023         return ret;
1024 }
1025
1026 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
1027 {
1028         kfree(dev_attr->attr.name);
1029 }
1030
1031 int __iio_add_chan_devattr(const char *postfix,
1032                            struct iio_chan_spec const *chan,
1033                            ssize_t (*readfunc)(struct device *dev,
1034                                                struct device_attribute *attr,
1035                                                char *buf),
1036                            ssize_t (*writefunc)(struct device *dev,
1037                                                 struct device_attribute *attr,
1038                                                 const char *buf,
1039                                                 size_t len),
1040                            u64 mask,
1041                            enum iio_shared_by shared_by,
1042                            struct device *dev,
1043                            struct list_head *attr_list)
1044 {
1045         int ret;
1046         struct iio_dev_attr *iio_attr, *t;
1047
1048         iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);
1049         if (iio_attr == NULL)
1050                 return -ENOMEM;
1051         ret = __iio_device_attr_init(&iio_attr->dev_attr,
1052                                      postfix, chan,
1053                                      readfunc, writefunc, shared_by);
1054         if (ret)
1055                 goto error_iio_dev_attr_free;
1056         iio_attr->c = chan;
1057         iio_attr->address = mask;
1058         list_for_each_entry(t, attr_list, l)
1059                 if (strcmp(t->dev_attr.attr.name,
1060                            iio_attr->dev_attr.attr.name) == 0) {
1061                         if (shared_by == IIO_SEPARATE)
1062                                 dev_err(dev, "tried to double register : %s\n",
1063                                         t->dev_attr.attr.name);
1064                         ret = -EBUSY;
1065                         goto error_device_attr_deinit;
1066                 }
1067         list_add(&iio_attr->l, attr_list);
1068
1069         return 0;
1070
1071 error_device_attr_deinit:
1072         __iio_device_attr_deinit(&iio_attr->dev_attr);
1073 error_iio_dev_attr_free:
1074         kfree(iio_attr);
1075         return ret;
1076 }
1077
1078 static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
1079                                          struct iio_chan_spec const *chan,
1080                                          enum iio_shared_by shared_by,
1081                                          const long *infomask)
1082 {
1083         int i, ret, attrcount = 0;
1084
1085         for_each_set_bit(i, infomask, sizeof(*infomask)*8) {
1086                 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
1087                         return -EINVAL;
1088                 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
1089                                              chan,
1090                                              &iio_read_channel_info,
1091                                              &iio_write_channel_info,
1092                                              i,
1093                                              shared_by,
1094                                              &indio_dev->dev,
1095                                              &indio_dev->channel_attr_list);
1096                 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1097                         continue;
1098                 else if (ret < 0)
1099                         return ret;
1100                 attrcount++;
1101         }
1102
1103         return attrcount;
1104 }
1105
1106 static int iio_device_add_info_mask_type_avail(struct iio_dev *indio_dev,
1107                                                struct iio_chan_spec const *chan,
1108                                                enum iio_shared_by shared_by,
1109                                                const long *infomask)
1110 {
1111         int i, ret, attrcount = 0;
1112         char *avail_postfix;
1113
1114         for_each_set_bit(i, infomask, sizeof(*infomask) * 8) {
1115                 avail_postfix = kasprintf(GFP_KERNEL,
1116                                           "%s_available",
1117                                           iio_chan_info_postfix[i]);
1118                 if (!avail_postfix)
1119                         return -ENOMEM;
1120
1121                 ret = __iio_add_chan_devattr(avail_postfix,
1122                                              chan,
1123                                              &iio_read_channel_info_avail,
1124                                              NULL,
1125                                              i,
1126                                              shared_by,
1127                                              &indio_dev->dev,
1128                                              &indio_dev->channel_attr_list);
1129                 kfree(avail_postfix);
1130                 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1131                         continue;
1132                 else if (ret < 0)
1133                         return ret;
1134                 attrcount++;
1135         }
1136
1137         return attrcount;
1138 }
1139
1140 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
1141                                         struct iio_chan_spec const *chan)
1142 {
1143         int ret, attrcount = 0;
1144         const struct iio_chan_spec_ext_info *ext_info;
1145
1146         if (chan->channel < 0)
1147                 return 0;
1148         ret = iio_device_add_info_mask_type(indio_dev, chan,
1149                                             IIO_SEPARATE,
1150                                             &chan->info_mask_separate);
1151         if (ret < 0)
1152                 return ret;
1153         attrcount += ret;
1154
1155         ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1156                                                   IIO_SEPARATE,
1157                                                   &chan->
1158                                                   info_mask_separate_available);
1159         if (ret < 0)
1160                 return ret;
1161         attrcount += ret;
1162
1163         ret = iio_device_add_info_mask_type(indio_dev, chan,
1164                                             IIO_SHARED_BY_TYPE,
1165                                             &chan->info_mask_shared_by_type);
1166         if (ret < 0)
1167                 return ret;
1168         attrcount += ret;
1169
1170         ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1171                                                   IIO_SHARED_BY_TYPE,
1172                                                   &chan->
1173                                                   info_mask_shared_by_type_available);
1174         if (ret < 0)
1175                 return ret;
1176         attrcount += ret;
1177
1178         ret = iio_device_add_info_mask_type(indio_dev, chan,
1179                                             IIO_SHARED_BY_DIR,
1180                                             &chan->info_mask_shared_by_dir);
1181         if (ret < 0)
1182                 return ret;
1183         attrcount += ret;
1184
1185         ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1186                                                   IIO_SHARED_BY_DIR,
1187                                                   &chan->info_mask_shared_by_dir_available);
1188         if (ret < 0)
1189                 return ret;
1190         attrcount += ret;
1191
1192         ret = iio_device_add_info_mask_type(indio_dev, chan,
1193                                             IIO_SHARED_BY_ALL,
1194                                             &chan->info_mask_shared_by_all);
1195         if (ret < 0)
1196                 return ret;
1197         attrcount += ret;
1198
1199         ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1200                                                   IIO_SHARED_BY_ALL,
1201                                                   &chan->info_mask_shared_by_all_available);
1202         if (ret < 0)
1203                 return ret;
1204         attrcount += ret;
1205
1206         if (chan->ext_info) {
1207                 unsigned int i = 0;
1208                 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
1209                         ret = __iio_add_chan_devattr(ext_info->name,
1210                                         chan,
1211                                         ext_info->read ?
1212                                             &iio_read_channel_ext_info : NULL,
1213                                         ext_info->write ?
1214                                             &iio_write_channel_ext_info : NULL,
1215                                         i,
1216                                         ext_info->shared,
1217                                         &indio_dev->dev,
1218                                         &indio_dev->channel_attr_list);
1219                         i++;
1220                         if (ret == -EBUSY && ext_info->shared)
1221                                 continue;
1222
1223                         if (ret)
1224                                 return ret;
1225
1226                         attrcount++;
1227                 }
1228         }
1229
1230         return attrcount;
1231 }
1232
1233 /**
1234  * iio_free_chan_devattr_list() - Free a list of IIO device attributes
1235  * @attr_list: List of IIO device attributes
1236  *
1237  * This function frees the memory allocated for each of the IIO device
1238  * attributes in the list.
1239  */
1240 void iio_free_chan_devattr_list(struct list_head *attr_list)
1241 {
1242         struct iio_dev_attr *p, *n;
1243
1244         list_for_each_entry_safe(p, n, attr_list, l) {
1245                 kfree(p->dev_attr.attr.name);
1246                 list_del(&p->l);
1247                 kfree(p);
1248         }
1249 }
1250
1251 static ssize_t iio_show_dev_name(struct device *dev,
1252                                  struct device_attribute *attr,
1253                                  char *buf)
1254 {
1255         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1256         return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name);
1257 }
1258
1259 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
1260
1261 static ssize_t iio_show_timestamp_clock(struct device *dev,
1262                                         struct device_attribute *attr,
1263                                         char *buf)
1264 {
1265         const struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1266         const clockid_t clk = iio_device_get_clock(indio_dev);
1267         const char *name;
1268         ssize_t sz;
1269
1270         switch (clk) {
1271         case CLOCK_REALTIME:
1272                 name = "realtime\n";
1273                 sz = sizeof("realtime\n");
1274                 break;
1275         case CLOCK_MONOTONIC:
1276                 name = "monotonic\n";
1277                 sz = sizeof("monotonic\n");
1278                 break;
1279         case CLOCK_MONOTONIC_RAW:
1280                 name = "monotonic_raw\n";
1281                 sz = sizeof("monotonic_raw\n");
1282                 break;
1283         case CLOCK_REALTIME_COARSE:
1284                 name = "realtime_coarse\n";
1285                 sz = sizeof("realtime_coarse\n");
1286                 break;
1287         case CLOCK_MONOTONIC_COARSE:
1288                 name = "monotonic_coarse\n";
1289                 sz = sizeof("monotonic_coarse\n");
1290                 break;
1291         case CLOCK_BOOTTIME:
1292                 name = "boottime\n";
1293                 sz = sizeof("boottime\n");
1294                 break;
1295         case CLOCK_TAI:
1296                 name = "tai\n";
1297                 sz = sizeof("tai\n");
1298                 break;
1299         default:
1300                 BUG();
1301         }
1302
1303         memcpy(buf, name, sz);
1304         return sz;
1305 }
1306
1307 static ssize_t iio_store_timestamp_clock(struct device *dev,
1308                                          struct device_attribute *attr,
1309                                          const char *buf, size_t len)
1310 {
1311         clockid_t clk;
1312         int ret;
1313
1314         if (sysfs_streq(buf, "realtime"))
1315                 clk = CLOCK_REALTIME;
1316         else if (sysfs_streq(buf, "monotonic"))
1317                 clk = CLOCK_MONOTONIC;
1318         else if (sysfs_streq(buf, "monotonic_raw"))
1319                 clk = CLOCK_MONOTONIC_RAW;
1320         else if (sysfs_streq(buf, "realtime_coarse"))
1321                 clk = CLOCK_REALTIME_COARSE;
1322         else if (sysfs_streq(buf, "monotonic_coarse"))
1323                 clk = CLOCK_MONOTONIC_COARSE;
1324         else if (sysfs_streq(buf, "boottime"))
1325                 clk = CLOCK_BOOTTIME;
1326         else if (sysfs_streq(buf, "tai"))
1327                 clk = CLOCK_TAI;
1328         else
1329                 return -EINVAL;
1330
1331         ret = iio_device_set_clock(dev_to_iio_dev(dev), clk);
1332         if (ret)
1333                 return ret;
1334
1335         return len;
1336 }
1337
1338 static DEVICE_ATTR(current_timestamp_clock, S_IRUGO | S_IWUSR,
1339                    iio_show_timestamp_clock, iio_store_timestamp_clock);
1340
1341 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
1342 {
1343         int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
1344         struct iio_dev_attr *p;
1345         struct attribute **attr, *clk = NULL;
1346
1347         /* First count elements in any existing group */
1348         if (indio_dev->info->attrs) {
1349                 attr = indio_dev->info->attrs->attrs;
1350                 while (*attr++ != NULL)
1351                         attrcount_orig++;
1352         }
1353         attrcount = attrcount_orig;
1354         /*
1355          * New channel registration method - relies on the fact a group does
1356          * not need to be initialized if its name is NULL.
1357          */
1358         if (indio_dev->channels)
1359                 for (i = 0; i < indio_dev->num_channels; i++) {
1360                         const struct iio_chan_spec *chan =
1361                                 &indio_dev->channels[i];
1362
1363                         if (chan->type == IIO_TIMESTAMP)
1364                                 clk = &dev_attr_current_timestamp_clock.attr;
1365
1366                         ret = iio_device_add_channel_sysfs(indio_dev, chan);
1367                         if (ret < 0)
1368                                 goto error_clear_attrs;
1369                         attrcount += ret;
1370                 }
1371
1372         if (indio_dev->event_interface)
1373                 clk = &dev_attr_current_timestamp_clock.attr;
1374
1375         if (indio_dev->name)
1376                 attrcount++;
1377         if (clk)
1378                 attrcount++;
1379
1380         indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
1381                                                    sizeof(indio_dev->chan_attr_group.attrs[0]),
1382                                                    GFP_KERNEL);
1383         if (indio_dev->chan_attr_group.attrs == NULL) {
1384                 ret = -ENOMEM;
1385                 goto error_clear_attrs;
1386         }
1387         /* Copy across original attributes */
1388         if (indio_dev->info->attrs)
1389                 memcpy(indio_dev->chan_attr_group.attrs,
1390                        indio_dev->info->attrs->attrs,
1391                        sizeof(indio_dev->chan_attr_group.attrs[0])
1392                        *attrcount_orig);
1393         attrn = attrcount_orig;
1394         /* Add all elements from the list. */
1395         list_for_each_entry(p, &indio_dev->channel_attr_list, l)
1396                 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
1397         if (indio_dev->name)
1398                 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
1399         if (clk)
1400                 indio_dev->chan_attr_group.attrs[attrn++] = clk;
1401
1402         indio_dev->groups[indio_dev->groupcounter++] =
1403                 &indio_dev->chan_attr_group;
1404
1405         return 0;
1406
1407 error_clear_attrs:
1408         iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1409
1410         return ret;
1411 }
1412
1413 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
1414 {
1415
1416         iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1417         kfree(indio_dev->chan_attr_group.attrs);
1418         indio_dev->chan_attr_group.attrs = NULL;
1419 }
1420
1421 static void iio_dev_release(struct device *device)
1422 {
1423         struct iio_dev *indio_dev = dev_to_iio_dev(device);
1424         if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1425                 iio_device_unregister_trigger_consumer(indio_dev);
1426         iio_device_unregister_eventset(indio_dev);
1427         iio_device_unregister_sysfs(indio_dev);
1428
1429         iio_buffer_put(indio_dev->buffer);
1430
1431         ida_simple_remove(&iio_ida, indio_dev->id);
1432         kfree(indio_dev);
1433 }
1434
1435 struct device_type iio_device_type = {
1436         .name = "iio_device",
1437         .release = iio_dev_release,
1438 };
1439
1440 /**
1441  * iio_device_alloc() - allocate an iio_dev from a driver
1442  * @sizeof_priv:        Space to allocate for private structure.
1443  **/
1444 struct iio_dev *iio_device_alloc(int sizeof_priv)
1445 {
1446         struct iio_dev *dev;
1447         size_t alloc_size;
1448
1449         alloc_size = sizeof(struct iio_dev);
1450         if (sizeof_priv) {
1451                 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
1452                 alloc_size += sizeof_priv;
1453         }
1454         /* ensure 32-byte alignment of whole construct ? */
1455         alloc_size += IIO_ALIGN - 1;
1456
1457         dev = kzalloc(alloc_size, GFP_KERNEL);
1458
1459         if (dev) {
1460                 dev->dev.groups = dev->groups;
1461                 dev->dev.type = &iio_device_type;
1462                 dev->dev.bus = &iio_bus_type;
1463                 device_initialize(&dev->dev);
1464                 dev_set_drvdata(&dev->dev, (void *)dev);
1465                 mutex_init(&dev->mlock);
1466                 mutex_init(&dev->info_exist_lock);
1467                 INIT_LIST_HEAD(&dev->channel_attr_list);
1468
1469                 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
1470                 if (dev->id < 0) {
1471                         /* cannot use a dev_err as the name isn't available */
1472                         pr_err("failed to get device id\n");
1473                         kfree(dev);
1474                         return NULL;
1475                 }
1476                 dev_set_name(&dev->dev, "iio:device%d", dev->id);
1477                 INIT_LIST_HEAD(&dev->buffer_list);
1478         }
1479
1480         return dev;
1481 }
1482 EXPORT_SYMBOL(iio_device_alloc);
1483
1484 /**
1485  * iio_device_free() - free an iio_dev from a driver
1486  * @dev:                the iio_dev associated with the device
1487  **/
1488 void iio_device_free(struct iio_dev *dev)
1489 {
1490         if (dev)
1491                 put_device(&dev->dev);
1492 }
1493 EXPORT_SYMBOL(iio_device_free);
1494
1495 static void devm_iio_device_release(struct device *dev, void *res)
1496 {
1497         iio_device_free(*(struct iio_dev **)res);
1498 }
1499
1500 int devm_iio_device_match(struct device *dev, void *res, void *data)
1501 {
1502         struct iio_dev **r = res;
1503         if (!r || !*r) {
1504                 WARN_ON(!r || !*r);
1505                 return 0;
1506         }
1507         return *r == data;
1508 }
1509 EXPORT_SYMBOL_GPL(devm_iio_device_match);
1510
1511 /**
1512  * devm_iio_device_alloc - Resource-managed iio_device_alloc()
1513  * @dev:                Device to allocate iio_dev for
1514  * @sizeof_priv:        Space to allocate for private structure.
1515  *
1516  * Managed iio_device_alloc. iio_dev allocated with this function is
1517  * automatically freed on driver detach.
1518  *
1519  * If an iio_dev allocated with this function needs to be freed separately,
1520  * devm_iio_device_free() must be used.
1521  *
1522  * RETURNS:
1523  * Pointer to allocated iio_dev on success, NULL on failure.
1524  */
1525 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)
1526 {
1527         struct iio_dev **ptr, *iio_dev;
1528
1529         ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),
1530                            GFP_KERNEL);
1531         if (!ptr)
1532                 return NULL;
1533
1534         iio_dev = iio_device_alloc(sizeof_priv);
1535         if (iio_dev) {
1536                 *ptr = iio_dev;
1537                 devres_add(dev, ptr);
1538         } else {
1539                 devres_free(ptr);
1540         }
1541
1542         return iio_dev;
1543 }
1544 EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
1545
1546 /**
1547  * devm_iio_device_free - Resource-managed iio_device_free()
1548  * @dev:                Device this iio_dev belongs to
1549  * @iio_dev:            the iio_dev associated with the device
1550  *
1551  * Free iio_dev allocated with devm_iio_device_alloc().
1552  */
1553 void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev)
1554 {
1555         int rc;
1556
1557         rc = devres_release(dev, devm_iio_device_release,
1558                             devm_iio_device_match, iio_dev);
1559         WARN_ON(rc);
1560 }
1561 EXPORT_SYMBOL_GPL(devm_iio_device_free);
1562
1563 /**
1564  * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1565  * @inode:      Inode structure for identifying the device in the file system
1566  * @filp:       File structure for iio device used to keep and later access
1567  *              private data
1568  *
1569  * Return: 0 on success or -EBUSY if the device is already opened
1570  **/
1571 static int iio_chrdev_open(struct inode *inode, struct file *filp)
1572 {
1573         struct iio_dev *indio_dev = container_of(inode->i_cdev,
1574                                                 struct iio_dev, chrdev);
1575
1576         if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
1577                 return -EBUSY;
1578
1579         iio_device_get(indio_dev);
1580
1581         filp->private_data = indio_dev;
1582
1583         return 0;
1584 }
1585
1586 /**
1587  * iio_chrdev_release() - chrdev file close buffer access and ioctls
1588  * @inode:      Inode structure pointer for the char device
1589  * @filp:       File structure pointer for the char device
1590  *
1591  * Return: 0 for successful release
1592  */
1593 static int iio_chrdev_release(struct inode *inode, struct file *filp)
1594 {
1595         struct iio_dev *indio_dev = container_of(inode->i_cdev,
1596                                                 struct iio_dev, chrdev);
1597         clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
1598         iio_device_put(indio_dev);
1599
1600         return 0;
1601 }
1602
1603 /* Somewhat of a cross file organization violation - ioctls here are actually
1604  * event related */
1605 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1606 {
1607         struct iio_dev *indio_dev = filp->private_data;
1608         int __user *ip = (int __user *)arg;
1609         int fd;
1610
1611         if (!indio_dev->info)
1612                 return -ENODEV;
1613
1614         if (cmd == IIO_GET_EVENT_FD_IOCTL) {
1615                 fd = iio_event_getfd(indio_dev);
1616                 if (fd < 0)
1617                         return fd;
1618                 if (copy_to_user(ip, &fd, sizeof(fd)))
1619                         return -EFAULT;
1620                 return 0;
1621         }
1622         return -EINVAL;
1623 }
1624
1625 static const struct file_operations iio_buffer_fileops = {
1626         .read = iio_buffer_read_first_n_outer_addr,
1627         .release = iio_chrdev_release,
1628         .open = iio_chrdev_open,
1629         .poll = iio_buffer_poll_addr,
1630         .owner = THIS_MODULE,
1631         .llseek = noop_llseek,
1632         .unlocked_ioctl = iio_ioctl,
1633         .compat_ioctl = iio_ioctl,
1634 };
1635
1636 static int iio_check_unique_scan_index(struct iio_dev *indio_dev)
1637 {
1638         int i, j;
1639         const struct iio_chan_spec *channels = indio_dev->channels;
1640
1641         if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))
1642                 return 0;
1643
1644         for (i = 0; i < indio_dev->num_channels - 1; i++) {
1645                 if (channels[i].scan_index < 0)
1646                         continue;
1647                 for (j = i + 1; j < indio_dev->num_channels; j++)
1648                         if (channels[i].scan_index == channels[j].scan_index) {
1649                                 dev_err(&indio_dev->dev,
1650                                         "Duplicate scan index %d\n",
1651                                         channels[i].scan_index);
1652                                 return -EINVAL;
1653                         }
1654         }
1655
1656         return 0;
1657 }
1658
1659 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
1660
1661 int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
1662 {
1663         int ret;
1664
1665         indio_dev->driver_module = this_mod;
1666         /* If the calling driver did not initialize of_node, do it here */
1667         if (!indio_dev->dev.of_node && indio_dev->dev.parent)
1668                 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
1669
1670         ret = iio_check_unique_scan_index(indio_dev);
1671         if (ret < 0)
1672                 return ret;
1673
1674         /* configure elements for the chrdev */
1675         indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
1676
1677         ret = iio_device_register_debugfs(indio_dev);
1678         if (ret) {
1679                 dev_err(indio_dev->dev.parent,
1680                         "Failed to register debugfs interfaces\n");
1681                 return ret;
1682         }
1683
1684         ret = iio_buffer_alloc_sysfs_and_mask(indio_dev);
1685         if (ret) {
1686                 dev_err(indio_dev->dev.parent,
1687                         "Failed to create buffer sysfs interfaces\n");
1688                 goto error_unreg_debugfs;
1689         }
1690
1691         ret = iio_device_register_sysfs(indio_dev);
1692         if (ret) {
1693                 dev_err(indio_dev->dev.parent,
1694                         "Failed to register sysfs interfaces\n");
1695                 goto error_buffer_free_sysfs;
1696         }
1697         ret = iio_device_register_eventset(indio_dev);
1698         if (ret) {
1699                 dev_err(indio_dev->dev.parent,
1700                         "Failed to register event set\n");
1701                 goto error_free_sysfs;
1702         }
1703         if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1704                 iio_device_register_trigger_consumer(indio_dev);
1705
1706         if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1707                 indio_dev->setup_ops == NULL)
1708                 indio_dev->setup_ops = &noop_ring_setup_ops;
1709
1710         cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1711
1712         indio_dev->chrdev.owner = this_mod;
1713
1714         ret = cdev_device_add(&indio_dev->chrdev, &indio_dev->dev);
1715         if (ret < 0)
1716                 goto error_unreg_eventset;
1717
1718         return 0;
1719
1720 error_unreg_eventset:
1721         iio_device_unregister_eventset(indio_dev);
1722 error_free_sysfs:
1723         iio_device_unregister_sysfs(indio_dev);
1724 error_buffer_free_sysfs:
1725         iio_buffer_free_sysfs_and_mask(indio_dev);
1726 error_unreg_debugfs:
1727         iio_device_unregister_debugfs(indio_dev);
1728         return ret;
1729 }
1730 EXPORT_SYMBOL(__iio_device_register);
1731
1732 /**
1733  * iio_device_unregister() - unregister a device from the IIO subsystem
1734  * @indio_dev:          Device structure representing the device.
1735  **/
1736 void iio_device_unregister(struct iio_dev *indio_dev)
1737 {
1738         mutex_lock(&indio_dev->info_exist_lock);
1739
1740         cdev_device_del(&indio_dev->chrdev, &indio_dev->dev);
1741
1742         iio_device_unregister_debugfs(indio_dev);
1743
1744         iio_disable_all_buffers(indio_dev);
1745
1746         indio_dev->info = NULL;
1747
1748         iio_device_wakeup_eventset(indio_dev);
1749         iio_buffer_wakeup_poll(indio_dev);
1750
1751         mutex_unlock(&indio_dev->info_exist_lock);
1752
1753         iio_buffer_free_sysfs_and_mask(indio_dev);
1754 }
1755 EXPORT_SYMBOL(iio_device_unregister);
1756
1757 static void devm_iio_device_unreg(struct device *dev, void *res)
1758 {
1759         iio_device_unregister(*(struct iio_dev **)res);
1760 }
1761
1762 int __devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev,
1763                                struct module *this_mod)
1764 {
1765         struct iio_dev **ptr;
1766         int ret;
1767
1768         ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL);
1769         if (!ptr)
1770                 return -ENOMEM;
1771
1772         *ptr = indio_dev;
1773         ret = __iio_device_register(indio_dev, this_mod);
1774         if (!ret)
1775                 devres_add(dev, ptr);
1776         else
1777                 devres_free(ptr);
1778
1779         return ret;
1780 }
1781 EXPORT_SYMBOL_GPL(__devm_iio_device_register);
1782
1783 /**
1784  * devm_iio_device_unregister - Resource-managed iio_device_unregister()
1785  * @dev:        Device this iio_dev belongs to
1786  * @indio_dev:  the iio_dev associated with the device
1787  *
1788  * Unregister iio_dev registered with devm_iio_device_register().
1789  */
1790 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev)
1791 {
1792         int rc;
1793
1794         rc = devres_release(dev, devm_iio_device_unreg,
1795                             devm_iio_device_match, indio_dev);
1796         WARN_ON(rc);
1797 }
1798 EXPORT_SYMBOL_GPL(devm_iio_device_unregister);
1799
1800 /**
1801  * iio_device_claim_direct_mode - Keep device in direct mode
1802  * @indio_dev:  the iio_dev associated with the device
1803  *
1804  * If the device is in direct mode it is guaranteed to stay
1805  * that way until iio_device_release_direct_mode() is called.
1806  *
1807  * Use with iio_device_release_direct_mode()
1808  *
1809  * Returns: 0 on success, -EBUSY on failure
1810  */
1811 int iio_device_claim_direct_mode(struct iio_dev *indio_dev)
1812 {
1813         mutex_lock(&indio_dev->mlock);
1814
1815         if (iio_buffer_enabled(indio_dev)) {
1816                 mutex_unlock(&indio_dev->mlock);
1817                 return -EBUSY;
1818         }
1819         return 0;
1820 }
1821 EXPORT_SYMBOL_GPL(iio_device_claim_direct_mode);
1822
1823 /**
1824  * iio_device_release_direct_mode - releases claim on direct mode
1825  * @indio_dev:  the iio_dev associated with the device
1826  *
1827  * Release the claim. Device is no longer guaranteed to stay
1828  * in direct mode.
1829  *
1830  * Use with iio_device_claim_direct_mode()
1831  */
1832 void iio_device_release_direct_mode(struct iio_dev *indio_dev)
1833 {
1834         mutex_unlock(&indio_dev->mlock);
1835 }
1836 EXPORT_SYMBOL_GPL(iio_device_release_direct_mode);
1837
1838 subsys_initcall(iio_init);
1839 module_exit(iio_exit);
1840
1841 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1842 MODULE_DESCRIPTION("Industrial I/O core");
1843 MODULE_LICENSE("GPL");