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         [IIO_MASSCONCENTRATION] = "massconcentration",
  91 };
  92
  93 static const char * const iio_modifier_names[] = {
  94         [IIO_MOD_X] = "x",
  95         [IIO_MOD_Y] = "y",
  96         [IIO_MOD_Z] = "z",
  97         [IIO_MOD_X_AND_Y] = "x&y",
  98         [IIO_MOD_X_AND_Z] = "x&z",
  99         [IIO_MOD_Y_AND_Z] = "y&z",
 100         [IIO_MOD_X_AND_Y_AND_Z] = "x&y&z",
 101         [IIO_MOD_X_OR_Y] = "x|y",
 102         [IIO_MOD_X_OR_Z] = "x|z",
 103         [IIO_MOD_Y_OR_Z] = "y|z",
 104         [IIO_MOD_X_OR_Y_OR_Z] = "x|y|z",
 105         [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
 106         [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
 107         [IIO_MOD_LIGHT_BOTH] = "both",
 108         [IIO_MOD_LIGHT_IR] = "ir",
 109         [IIO_MOD_LIGHT_CLEAR] = "clear",
 110         [IIO_MOD_LIGHT_RED] = "red",
 111         [IIO_MOD_LIGHT_GREEN] = "green",
 112         [IIO_MOD_LIGHT_BLUE] = "blue",
 113         [IIO_MOD_LIGHT_UV] = "uv",
 114         [IIO_MOD_LIGHT_DUV] = "duv",
 115         [IIO_MOD_QUATERNION] = "quaternion",
 116         [IIO_MOD_TEMP_AMBIENT] = "ambient",
 117         [IIO_MOD_TEMP_OBJECT] = "object",
 118         [IIO_MOD_NORTH_MAGN] = "from_north_magnetic",
 119         [IIO_MOD_NORTH_TRUE] = "from_north_true",
 120         [IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",
 121         [IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",
 122         [IIO_MOD_RUNNING] = "running",
 123         [IIO_MOD_JOGGING] = "jogging",
 124         [IIO_MOD_WALKING] = "walking",
 125         [IIO_MOD_STILL] = "still",
 126         [IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",
 127         [IIO_MOD_I] = "i",
 128         [IIO_MOD_Q] = "q",
 129         [IIO_MOD_CO2] = "co2",
 130         [IIO_MOD_VOC] = "voc",
 131         [IIO_MOD_PM1] = "pm1",
 132         [IIO_MOD_PM2P5] = "pm2p5",
 133         [IIO_MOD_PM4] = "pm4",
 134         [IIO_MOD_PM10] = "pm10",
 135 };
 136
 137 /* relies on pairs of these shared then separate */
 138 static const char * const iio_chan_info_postfix[] = {
 139         [IIO_CHAN_INFO_RAW] = "raw",
 140         [IIO_CHAN_INFO_PROCESSED] = "input",
 141         [IIO_CHAN_INFO_SCALE] = "scale",
 142         [IIO_CHAN_INFO_OFFSET] = "offset",
 143         [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
 144         [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
 145         [IIO_CHAN_INFO_PEAK] = "peak_raw",
 146         [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
 147         [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
 148         [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
 149         [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
 150         = "filter_low_pass_3db_frequency",
 151         [IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY]
 152         = "filter_high_pass_3db_frequency",
 153         [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
 154         [IIO_CHAN_INFO_FREQUENCY] = "frequency",
 155         [IIO_CHAN_INFO_PHASE] = "phase",
 156         [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
 157         [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
 158         [IIO_CHAN_INFO_INT_TIME] = "integration_time",
 159         [IIO_CHAN_INFO_ENABLE] = "en",
 160         [IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
 161         [IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",
 162         [IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count",
 163         [IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time",
 164         [IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity",
 165         [IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio",
 166 };
 167
 168 /**
 169  * iio_find_channel_from_si() - get channel from its scan index
 170  * @indio_dev:          device
 171  * @si:                 scan index to match
 172  */
 173 const struct iio_chan_spec
 174 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
 175 {
 176         int i;
 177
 178         for (i = 0; i < indio_dev->num_channels; i++)
 179                 if (indio_dev->channels[i].scan_index == si)
 180                         return &indio_dev->channels[i];
 181         return NULL;
 182 }
 183
 184 /* This turns up an awful lot */
 185 ssize_t iio_read_const_attr(struct device *dev,
 186                             struct device_attribute *attr,
 187                             char *buf)
 188 {
 189         return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
 190 }
 191 EXPORT_SYMBOL(iio_read_const_attr);
 192
 193 static int iio_device_set_clock(struct iio_dev *indio_dev, clockid_t clock_id)
 194 {
 195         int ret;
 196         const struct iio_event_interface *ev_int = indio_dev->event_interface;
 197
 198         ret = mutex_lock_interruptible(&indio_dev->mlock);
 199         if (ret)
 200                 return ret;
 201         if ((ev_int && iio_event_enabled(ev_int)) ||
 202             iio_buffer_enabled(indio_dev)) {
 203                 mutex_unlock(&indio_dev->mlock);
 204                 return -EBUSY;
 205         }
 206         indio_dev->clock_id = clock_id;
 207         mutex_unlock(&indio_dev->mlock);
 208
 209         return 0;
 210 }
 211
 212 /**
 213  * iio_get_time_ns() - utility function to get a time stamp for events etc
 214  * @indio_dev: device
 215  */
 216 s64 iio_get_time_ns(const struct iio_dev *indio_dev)
 217 {
 218         struct timespec64 tp;
 219
 220         switch (iio_device_get_clock(indio_dev)) {
 221         case CLOCK_REALTIME:
 222                 return ktime_get_real_ns();
 223         case CLOCK_MONOTONIC:
 224                 return ktime_get_ns();
 225         case CLOCK_MONOTONIC_RAW:
 226                 return ktime_get_raw_ns();
 227         case CLOCK_REALTIME_COARSE:
 228                 return ktime_to_ns(ktime_get_coarse_real());
 229         case CLOCK_MONOTONIC_COARSE:
 230                 ktime_get_coarse_ts64(&tp);
 231                 return timespec64_to_ns(&tp);
 232         case CLOCK_BOOTTIME:
 233                 return ktime_get_boot_ns();
 234         case CLOCK_TAI:
 235                 return ktime_get_tai_ns();
 236         default:
 237                 BUG();
 238         }
 239 }
 240 EXPORT_SYMBOL(iio_get_time_ns);
 241
 242 /**
 243  * iio_get_time_res() - utility function to get time stamp clock resolution in
 244  *                      nano seconds.
 245  * @indio_dev: device
 246  */
 247 unsigned int iio_get_time_res(const struct iio_dev *indio_dev)
 248 {
 249         switch (iio_device_get_clock(indio_dev)) {
 250         case CLOCK_REALTIME:
 251         case CLOCK_MONOTONIC:
 252         case CLOCK_MONOTONIC_RAW:
 253         case CLOCK_BOOTTIME:
 254         case CLOCK_TAI:
 255                 return hrtimer_resolution;
 256         case CLOCK_REALTIME_COARSE:
 257         case CLOCK_MONOTONIC_COARSE:
 258                 return LOW_RES_NSEC;
 259         default:
 260                 BUG();
 261         }
 262 }
 263 EXPORT_SYMBOL(iio_get_time_res);
 264
 265 static int __init iio_init(void)
 266 {
 267         int ret;
 268
 269         /* Register sysfs bus */
 270         ret  = bus_register(&iio_bus_type);
 271         if (ret < 0) {
 272                 pr_err("could not register bus type\n");
 273                 goto error_nothing;
 274         }
 275
 276         ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
 277         if (ret < 0) {
 278                 pr_err("failed to allocate char dev region\n");
 279                 goto error_unregister_bus_type;
 280         }
 281
 282         iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
 283
 284         return 0;
 285
 286 error_unregister_bus_type:
 287         bus_unregister(&iio_bus_type);
 288 error_nothing:
 289         return ret;
 290 }
 291
 292 static void __exit iio_exit(void)
 293 {
 294         if (iio_devt)
 295                 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
 296         bus_unregister(&iio_bus_type);
 297         debugfs_remove(iio_debugfs_dentry);
 298 }
 299
 300 #if defined(CONFIG_DEBUG_FS)
 301 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
 302                               size_t count, loff_t *ppos)
 303 {
 304         struct iio_dev *indio_dev = file->private_data;
 305         char buf[20];
 306         unsigned val = 0;
 307         ssize_t len;
 308         int ret;
 309
 310         ret = indio_dev->info->debugfs_reg_access(indio_dev,
 311                                                   indio_dev->cached_reg_addr,
 312                                                   0, &val);
 313         if (ret) {
 314                 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
 315                 return ret;
 316         }
 317
 318         len = snprintf(buf, sizeof(buf), "0x%X\n", val);
 319
 320         return simple_read_from_buffer(userbuf, count, ppos, buf, len);
 321 }
 322
 323 static ssize_t iio_debugfs_write_reg(struct file *file,
 324                      const char __user *userbuf, size_t count, loff_t *ppos)
 325 {
 326         struct iio_dev *indio_dev = file->private_data;
 327         unsigned reg, val;
 328         char buf[80];
 329         int ret;
 330
 331         count = min_t(size_t, count, (sizeof(buf)-1));
 332         if (copy_from_user(buf, userbuf, count))
 333                 return -EFAULT;
 334
 335         buf[count] = 0;
 336
 337         ret = sscanf(buf, "%i %i", &reg, &val);
 338
 339         switch (ret) {
 340         case 1:
 341                 indio_dev->cached_reg_addr = reg;
 342                 break;
 343         case 2:
 344                 indio_dev->cached_reg_addr = reg;
 345                 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
 346                                                           val, NULL);
 347                 if (ret) {
 348                         dev_err(indio_dev->dev.parent, "%s: write failed\n",
 349                                 __func__);
 350                         return ret;
 351                 }
 352                 break;
 353         default:
 354                 return -EINVAL;
 355         }
 356
 357         return count;
 358 }
 359
 360 static const struct file_operations iio_debugfs_reg_fops = {
 361         .open = simple_open,
 362         .read = iio_debugfs_read_reg,
 363         .write = iio_debugfs_write_reg,
 364 };
 365
 366 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
 367 {
 368         debugfs_remove_recursive(indio_dev->debugfs_dentry);
 369 }
 370
 371 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
 372 {
 373         struct dentry *d;
 374
 375         if (indio_dev->info->debugfs_reg_access == NULL)
 376                 return 0;
 377
 378         if (!iio_debugfs_dentry)
 379                 return 0;
 380
 381         indio_dev->debugfs_dentry =
 382                 debugfs_create_dir(dev_name(&indio_dev->dev),
 383                                    iio_debugfs_dentry);
 384         if (indio_dev->debugfs_dentry == NULL) {
 385                 dev_warn(indio_dev->dev.parent,
 386                          "Failed to create debugfs directory\n");
 387                 return -EFAULT;
 388         }
 389
 390         d = debugfs_create_file("direct_reg_access", 0644,
 391                                 indio_dev->debugfs_dentry,
 392                                 indio_dev, &iio_debugfs_reg_fops);
 393         if (!d) {
 394                 iio_device_unregister_debugfs(indio_dev);
 395                 return -ENOMEM;
 396         }
 397
 398         return 0;
 399 }
 400 #else
 401 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
 402 {
 403         return 0;
 404 }
 405
 406 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
 407 {
 408 }
 409 #endif /* CONFIG_DEBUG_FS */
 410
 411 static ssize_t iio_read_channel_ext_info(struct device *dev,
 412                                      struct device_attribute *attr,
 413                                      char *buf)
 414 {
 415         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 416         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 417         const struct iio_chan_spec_ext_info *ext_info;
 418
 419         ext_info = &this_attr->c->ext_info[this_attr->address];
 420
 421         return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
 422 }
 423
 424 static ssize_t iio_write_channel_ext_info(struct device *dev,
 425                                      struct device_attribute *attr,
 426                                      const char *buf,
 427                                          size_t len)
 428 {
 429         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 430         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 431         const struct iio_chan_spec_ext_info *ext_info;
 432
 433         ext_info = &this_attr->c->ext_info[this_attr->address];
 434
 435         return ext_info->write(indio_dev, ext_info->private,
 436                                this_attr->c, buf, len);
 437 }
 438
 439 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
 440         uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
 441 {
 442         const struct iio_enum *e = (const struct iio_enum *)priv;
 443         unsigned int i;
 444         size_t len = 0;
 445
 446         if (!e->num_items)
 447                 return 0;
 448
 449         for (i = 0; i < e->num_items; ++i)
 450                 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
 451
 452         /* replace last space with a newline */
 453         buf[len - 1] = '\n';
 454
 455         return len;
 456 }
 457 EXPORT_SYMBOL_GPL(iio_enum_available_read);
 458
 459 ssize_t iio_enum_read(struct iio_dev *indio_dev,
 460         uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
 461 {
 462         const struct iio_enum *e = (const struct iio_enum *)priv;
 463         int i;
 464
 465         if (!e->get)
 466                 return -EINVAL;
 467
 468         i = e->get(indio_dev, chan);
 469         if (i < 0)
 470                 return i;
 471         else if (i >= e->num_items)
 472                 return -EINVAL;
 473
 474         return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
 475 }
 476 EXPORT_SYMBOL_GPL(iio_enum_read);
 477
 478 ssize_t iio_enum_write(struct iio_dev *indio_dev,
 479         uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
 480         size_t len)
 481 {
 482         const struct iio_enum *e = (const struct iio_enum *)priv;
 483         int ret;
 484
 485         if (!e->set)
 486                 return -EINVAL;
 487
 488         ret = __sysfs_match_string(e->items, e->num_items, buf);
 489         if (ret < 0)
 490                 return ret;
 491
 492         ret = e->set(indio_dev, chan, ret);
 493         return ret ? ret : len;
 494 }
 495 EXPORT_SYMBOL_GPL(iio_enum_write);
 496
 497 static const struct iio_mount_matrix iio_mount_idmatrix = {
 498         .rotation = {
 499                 "1", "0", "0",
 500                 "0", "1", "0",
 501                 "0", "0", "1"
 502         }
 503 };
 504
 505 static int iio_setup_mount_idmatrix(const struct device *dev,
 506                                     struct iio_mount_matrix *matrix)
 507 {
 508         *matrix = iio_mount_idmatrix;
 509         dev_info(dev, "mounting matrix not found: using identity...\n");
 510         return 0;
 511 }
 512
 513 ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
 514                               const struct iio_chan_spec *chan, char *buf)
 515 {
 516         const struct iio_mount_matrix *mtx = ((iio_get_mount_matrix_t *)
 517                                               priv)(indio_dev, chan);
 518
 519         if (IS_ERR(mtx))
 520                 return PTR_ERR(mtx);
 521
 522         if (!mtx)
 523                 mtx = &iio_mount_idmatrix;
 524
 525         return snprintf(buf, PAGE_SIZE, "%s, %s, %s; %s, %s, %s; %s, %s, %s\n",
 526                         mtx->rotation[0], mtx->rotation[1], mtx->rotation[2],
 527                         mtx->rotation[3], mtx->rotation[4], mtx->rotation[5],
 528                         mtx->rotation[6], mtx->rotation[7], mtx->rotation[8]);
 529 }
 530 EXPORT_SYMBOL_GPL(iio_show_mount_matrix);
 531
 532 /**
 533  * of_iio_read_mount_matrix() - retrieve iio device mounting matrix from
 534  *                              device-tree "mount-matrix" property
 535  * @dev:        device the mounting matrix property is assigned to
 536  * @propname:   device specific mounting matrix property name
 537  * @matrix:     where to store retrieved matrix
 538  *
 539  * If device is assigned no mounting matrix property, a default 3x3 identity
 540  * matrix will be filled in.
 541  *
 542  * Return: 0 if success, or a negative error code on failure.
 543  */
 544 #ifdef CONFIG_OF
 545 int of_iio_read_mount_matrix(const struct device *dev,
 546                              const char *propname,
 547                              struct iio_mount_matrix *matrix)
 548 {
 549         if (dev->of_node) {
 550                 int err = of_property_read_string_array(dev->of_node,
 551                                 propname, matrix->rotation,
 552                                 ARRAY_SIZE(iio_mount_idmatrix.rotation));
 553
 554                 if (err == ARRAY_SIZE(iio_mount_idmatrix.rotation))
 555                         return 0;
 556
 557                 if (err >= 0)
 558                         /* Invalid number of matrix entries. */
 559                         return -EINVAL;
 560
 561                 if (err != -EINVAL)
 562                         /* Invalid matrix declaration format. */
 563                         return err;
 564         }
 565
 566         /* Matrix was not declared at all: fallback to identity. */
 567         return iio_setup_mount_idmatrix(dev, matrix);
 568 }
 569 #else
 570 int of_iio_read_mount_matrix(const struct device *dev,
 571                              const char *propname,
 572                              struct iio_mount_matrix *matrix)
 573 {
 574         return iio_setup_mount_idmatrix(dev, matrix);
 575 }
 576 #endif
 577 EXPORT_SYMBOL(of_iio_read_mount_matrix);
 578
 579 static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
 580                                   int size, const int *vals)
 581 {
 582         unsigned long long tmp;
 583         int tmp0, tmp1;
 584         bool scale_db = false;
 585
 586         switch (type) {
 587         case IIO_VAL_INT:
 588                 return snprintf(buf, len, "%d", vals[0]);
 589         case IIO_VAL_INT_PLUS_MICRO_DB:
 590                 scale_db = true;
 591                 /* fall through */
 592         case IIO_VAL_INT_PLUS_MICRO:
 593                 if (vals[1] < 0)
 594                         return snprintf(buf, len, "-%d.%06u%s", abs(vals[0]),
 595                                         -vals[1], scale_db ? " dB" : "");
 596                 else
 597                         return snprintf(buf, len, "%d.%06u%s", vals[0], vals[1],
 598                                         scale_db ? " dB" : "");
 599         case IIO_VAL_INT_PLUS_NANO:
 600                 if (vals[1] < 0)
 601                         return snprintf(buf, len, "-%d.%09u", abs(vals[0]),
 602                                         -vals[1]);
 603                 else
 604                         return snprintf(buf, len, "%d.%09u", vals[0], vals[1]);
 605         case IIO_VAL_FRACTIONAL:
 606                 tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
 607                 tmp1 = vals[1];
 608                 tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1);
 609                 return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
 610         case IIO_VAL_FRACTIONAL_LOG2:
 611                 tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]);
 612                 tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1);
 613                 return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
 614         case IIO_VAL_INT_MULTIPLE:
 615         {
 616                 int i;
 617                 int l = 0;
 618
 619                 for (i = 0; i < size; ++i) {
 620                         l += snprintf(&buf[l], len - l, "%d ", vals[i]);
 621                         if (l >= len)
 622                                 break;
 623                 }
 624                 return l;
 625         }
 626         default:
 627                 return 0;
 628         }
 629 }
 630
 631 /**
 632  * iio_format_value() - Formats a IIO value into its string representation
 633  * @buf:        The buffer to which the formatted value gets written
 634  *              which is assumed to be big enough (i.e. PAGE_SIZE).
 635  * @type:       One of the IIO_VAL_* constants. This decides how the val
 636  *              and val2 parameters are formatted.
 637  * @size:       Number of IIO value entries contained in vals
 638  * @vals:       Pointer to the values, exact meaning depends on the
 639  *              type parameter.
 640  *
 641  * Return: 0 by default, a negative number on failure or the
 642  *         total number of characters written for a type that belongs
 643  *         to the IIO_VAL_* constant.
 644  */
 645 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
 646 {
 647         ssize_t len;
 648
 649         len = __iio_format_value(buf, PAGE_SIZE, type, size, vals);
 650         if (len >= PAGE_SIZE - 1)
 651                 return -EFBIG;
 652
 653         return len + sprintf(buf + len, "\n");
 654 }
 655 EXPORT_SYMBOL_GPL(iio_format_value);
 656
 657 static ssize_t iio_read_channel_info(struct device *dev,
 658                                      struct device_attribute *attr,
 659                                      char *buf)
 660 {
 661         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 662         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 663         int vals[INDIO_MAX_RAW_ELEMENTS];
 664         int ret;
 665         int val_len = 2;
 666
 667         if (indio_dev->info->read_raw_multi)
 668                 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
 669                                                         INDIO_MAX_RAW_ELEMENTS,
 670                                                         vals, &val_len,
 671                                                         this_attr->address);
 672         else
 673                 ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
 674                                     &vals[0], &vals[1], this_attr->address);
 675
 676         if (ret < 0)
 677                 return ret;
 678
 679         return iio_format_value(buf, ret, val_len, vals);
 680 }
 681
 682 static ssize_t iio_format_avail_list(char *buf, const int *vals,
 683                                      int type, int length)
 684 {
 685         int i;
 686         ssize_t len = 0;
 687
 688         switch (type) {
 689         case IIO_VAL_INT:
 690                 for (i = 0; i < length; i++) {
 691                         len += __iio_format_value(buf + len, PAGE_SIZE - len,
 692                                                   type, 1, &vals[i]);
 693                         if (len >= PAGE_SIZE)
 694                                 return -EFBIG;
 695                         if (i < length - 1)
 696                                 len += snprintf(buf + len, PAGE_SIZE - len,
 697                                                 " ");
 698                         else
 699                                 len += snprintf(buf + len, PAGE_SIZE - len,
 700                                                 "\n");
 701                         if (len >= PAGE_SIZE)
 702                                 return -EFBIG;
 703                 }
 704                 break;
 705         default:
 706                 for (i = 0; i < length / 2; i++) {
 707                         len += __iio_format_value(buf + len, PAGE_SIZE - len,
 708                                                   type, 2, &vals[i * 2]);
 709                         if (len >= PAGE_SIZE)
 710                                 return -EFBIG;
 711                         if (i < length / 2 - 1)
 712                                 len += snprintf(buf + len, PAGE_SIZE - len,
 713                                                 " ");
 714                         else
 715                                 len += snprintf(buf + len, PAGE_SIZE - len,
 716                                                 "\n");
 717                         if (len >= PAGE_SIZE)
 718                                 return -EFBIG;
 719                 }
 720         }
 721
 722         return len;
 723 }
 724
 725 static ssize_t iio_format_avail_range(char *buf, const int *vals, int type)
 726 {
 727         int i;
 728         ssize_t len;
 729
 730         len = snprintf(buf, PAGE_SIZE, "[");
 731         switch (type) {
 732         case IIO_VAL_INT:
 733                 for (i = 0; i < 3; i++) {
 734                         len += __iio_format_value(buf + len, PAGE_SIZE - len,
 735                                                   type, 1, &vals[i]);
 736                         if (len >= PAGE_SIZE)
 737                                 return -EFBIG;
 738                         if (i < 2)
 739                                 len += snprintf(buf + len, PAGE_SIZE - len,
 740                                                 " ");
 741                         else
 742                                 len += snprintf(buf + len, PAGE_SIZE - len,
 743                                                 "]\n");
 744                         if (len >= PAGE_SIZE)
 745                                 return -EFBIG;
 746                 }
 747                 break;
 748         default:
 749                 for (i = 0; i < 3; i++) {
 750                         len += __iio_format_value(buf + len, PAGE_SIZE - len,
 751                                                   type, 2, &vals[i * 2]);
 752                         if (len >= PAGE_SIZE)
 753                                 return -EFBIG;
 754                         if (i < 2)
 755                                 len += snprintf(buf + len, PAGE_SIZE - len,
 756                                                 " ");
 757                         else
 758                                 len += snprintf(buf + len, PAGE_SIZE - len,
 759                                                 "]\n");
 760                         if (len >= PAGE_SIZE)
 761                                 return -EFBIG;
 762                 }
 763         }
 764
 765         return len;
 766 }
 767
 768 static ssize_t iio_read_channel_info_avail(struct device *dev,
 769                                            struct device_attribute *attr,
 770                                            char *buf)
 771 {
 772         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 773         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 774         const int *vals;
 775         int ret;
 776         int length;
 777         int type;
 778
 779         ret = indio_dev->info->read_avail(indio_dev, this_attr->c,
 780                                           &vals, &type, &length,
 781                                           this_attr->address);
 782
 783         if (ret < 0)
 784                 return ret;
 785         switch (ret) {
 786         case IIO_AVAIL_LIST:
 787                 return iio_format_avail_list(buf, vals, type, length);
 788         case IIO_AVAIL_RANGE:
 789                 return iio_format_avail_range(buf, vals, type);
 790         default:
 791                 return -EINVAL;
 792         }
 793 }
 794
 795 /**
 796  * iio_str_to_fixpoint() - Parse a fixed-point number from a string
 797  * @str: The string to parse
 798  * @fract_mult: Multiplier for the first decimal place, should be a power of 10
 799  * @integer: The integer part of the number
 800  * @fract: The fractional part of the number
 801  *
 802  * Returns 0 on success, or a negative error code if the string could not be
 803  * parsed.
 804  */
 805 int iio_str_to_fixpoint(const char *str, int fract_mult,
 806         int *integer, int *fract)
 807 {
 808         int i = 0, f = 0;
 809         bool integer_part = true, negative = false;
 810
 811         if (fract_mult == 0) {
 812                 *fract = 0;
 813
 814                 return kstrtoint(str, 0, integer);
 815         }
 816
 817         if (str[0] == '-') {
 818                 negative = true;
 819                 str++;
 820         } else if (str[0] == '+') {
 821                 str++;
 822         }
 823
 824         while (*str) {
 825                 if ('0' <= *str && *str <= '9') {
 826                         if (integer_part) {
 827                                 i = i * 10 + *str - '0';
 828                         } else {
 829                                 f += fract_mult * (*str - '0');
 830                                 fract_mult /= 10;
 831                         }
 832                 } else if (*str == '\n') {
 833                         if (*(str + 1) == '\0')
 834                                 break;
 835                         else
 836                                 return -EINVAL;
 837                 } else if (*str == '.' && integer_part) {
 838                         integer_part = false;
 839                 } else {
 840                         return -EINVAL;
 841                 }
 842                 str++;
 843         }
 844
 845         if (negative) {
 846                 if (i)
 847                         i = -i;
 848                 else
 849                         f = -f;
 850         }
 851
 852         *integer = i;
 853         *fract = f;
 854
 855         return 0;
 856 }
 857 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
 858
 859 static ssize_t iio_write_channel_info(struct device *dev,
 860                                       struct device_attribute *attr,
 861                                       const char *buf,
 862                                       size_t len)
 863 {
 864         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 865         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 866         int ret, fract_mult = 100000;
 867         int integer, fract;
 868
 869         /* Assumes decimal - precision based on number of digits */
 870         if (!indio_dev->info->write_raw)
 871                 return -EINVAL;
 872
 873         if (indio_dev->info->write_raw_get_fmt)
 874                 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
 875                         this_attr->c, this_attr->address)) {
 876                 case IIO_VAL_INT:
 877                         fract_mult = 0;
 878                         break;
 879                 case IIO_VAL_INT_PLUS_MICRO:
 880                         fract_mult = 100000;
 881                         break;
 882                 case IIO_VAL_INT_PLUS_NANO:
 883                         fract_mult = 100000000;
 884                         break;
 885                 default:
 886                         return -EINVAL;
 887                 }
 888
 889         ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
 890         if (ret)
 891                 return ret;
 892
 893         ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
 894                                          integer, fract, this_attr->address);
 895         if (ret)
 896                 return ret;
 897
 898         return len;
 899 }
 900
 901 static
 902 int __iio_device_attr_init(struct device_attribute *dev_attr,
 903                            const char *postfix,
 904                            struct iio_chan_spec const *chan,
 905                            ssize_t (*readfunc)(struct device *dev,
 906                                                struct device_attribute *attr,
 907                                                char *buf),
 908                            ssize_t (*writefunc)(struct device *dev,
 909                                                 struct device_attribute *attr,
 910                                                 const char *buf,
 911                                                 size_t len),
 912                            enum iio_shared_by shared_by)
 913 {
 914         int ret = 0;
 915         char *name = NULL;
 916         char *full_postfix;
 917         sysfs_attr_init(&dev_attr->attr);
 918
 919         /* Build up postfix of <extend_name>_<modifier>_postfix */
 920         if (chan->modified && (shared_by == IIO_SEPARATE)) {
 921                 if (chan->extend_name)
 922                         full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
 923                                                  iio_modifier_names[chan
 924                                                                     ->channel2],
 925                                                  chan->extend_name,
 926                                                  postfix);
 927                 else
 928                         full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
 929                                                  iio_modifier_names[chan
 930                                                                     ->channel2],
 931                                                  postfix);
 932         } else {
 933                 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)
 934                         full_postfix = kstrdup(postfix, GFP_KERNEL);
 935                 else
 936                         full_postfix = kasprintf(GFP_KERNEL,
 937                                                  "%s_%s",
 938                                                  chan->extend_name,
 939                                                  postfix);
 940         }
 941         if (full_postfix == NULL)
 942                 return -ENOMEM;
 943
 944         if (chan->differential) { /* Differential can not have modifier */
 945                 switch (shared_by) {
 946                 case IIO_SHARED_BY_ALL:
 947                         name = kasprintf(GFP_KERNEL, "%s", full_postfix);
 948                         break;
 949                 case IIO_SHARED_BY_DIR:
 950                         name = kasprintf(GFP_KERNEL, "%s_%s",
 951                                                 iio_direction[chan->output],
 952                                                 full_postfix);
 953                         break;
 954                 case IIO_SHARED_BY_TYPE:
 955                         name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
 956                                             iio_direction[chan->output],
 957                                             iio_chan_type_name_spec[chan->type],
 958                                             iio_chan_type_name_spec[chan->type],
 959                                             full_postfix);
 960                         break;
 961                 case IIO_SEPARATE:
 962                         if (!chan->indexed) {
 963                                 WARN(1, "Differential channels must be indexed\n");
 964                                 ret = -EINVAL;
 965                                 goto error_free_full_postfix;
 966                         }
 967                         name = kasprintf(GFP_KERNEL,
 968                                             "%s_%s%d-%s%d_%s",
 969                                             iio_direction[chan->output],
 970                                             iio_chan_type_name_spec[chan->type],
 971                                             chan->channel,
 972                                             iio_chan_type_name_spec[chan->type],
 973                                             chan->channel2,
 974                                             full_postfix);
 975                         break;
 976                 }
 977         } else { /* Single ended */
 978                 switch (shared_by) {
 979                 case IIO_SHARED_BY_ALL:
 980                         name = kasprintf(GFP_KERNEL, "%s", full_postfix);
 981                         break;
 982                 case IIO_SHARED_BY_DIR:
 983                         name = kasprintf(GFP_KERNEL, "%s_%s",
 984                                                 iio_direction[chan->output],
 985                                                 full_postfix);
 986                         break;
 987                 case IIO_SHARED_BY_TYPE:
 988                         name = kasprintf(GFP_KERNEL, "%s_%s_%s",
 989                                             iio_direction[chan->output],
 990                                             iio_chan_type_name_spec[chan->type],
 991                                             full_postfix);
 992                         break;
 993
 994                 case IIO_SEPARATE:
 995                         if (chan->indexed)
 996                                 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
 997                                                     iio_direction[chan->output],
 998                                                     iio_chan_type_name_spec[chan->type],
 999                                                     chan->channel,
1000                                                     full_postfix);
1001                         else
1002                                 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
1003                                                     iio_direction[chan->output],
1004                                                     iio_chan_type_name_spec[chan->type],
1005                                                     full_postfix);
1006                         break;
1007                 }
1008         }
1009         if (name == NULL) {
1010                 ret = -ENOMEM;
1011                 goto error_free_full_postfix;
1012         }
1013         dev_attr->attr.name = name;
1014
1015         if (readfunc) {
1016                 dev_attr->attr.mode |= S_IRUGO;
1017                 dev_attr->show = readfunc;
1018         }
1019
1020         if (writefunc) {
1021                 dev_attr->attr.mode |= S_IWUSR;
1022                 dev_attr->store = writefunc;
1023         }
1024
1025 error_free_full_postfix:
1026         kfree(full_postfix);
1027
1028         return ret;
1029 }
1030
1031 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
1032 {
1033         kfree(dev_attr->attr.name);
1034 }
1035
1036 int __iio_add_chan_devattr(const char *postfix,
1037                            struct iio_chan_spec const *chan,
1038                            ssize_t (*readfunc)(struct device *dev,
1039                                                struct device_attribute *attr,
1040                                                char *buf),
1041                            ssize_t (*writefunc)(struct device *dev,
1042                                                 struct device_attribute *attr,
1043                                                 const char *buf,
1044                                                 size_t len),
1045                            u64 mask,
1046                            enum iio_shared_by shared_by,
1047                            struct device *dev,
1048                            struct list_head *attr_list)
1049 {
1050         int ret;
1051         struct iio_dev_attr *iio_attr, *t;
1052
1053         iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);
1054         if (iio_attr == NULL)
1055                 return -ENOMEM;
1056         ret = __iio_device_attr_init(&iio_attr->dev_attr,
1057                                      postfix, chan,
1058                                      readfunc, writefunc, shared_by);
1059         if (ret)
1060                 goto error_iio_dev_attr_free;
1061         iio_attr->c = chan;
1062         iio_attr->address = mask;
1063         list_for_each_entry(t, attr_list, l)
1064                 if (strcmp(t->dev_attr.attr.name,
1065                            iio_attr->dev_attr.attr.name) == 0) {
1066                         if (shared_by == IIO_SEPARATE)
1067                                 dev_err(dev, "tried to double register : %s\n",
1068                                         t->dev_attr.attr.name);
1069                         ret = -EBUSY;
1070                         goto error_device_attr_deinit;
1071                 }
1072         list_add(&iio_attr->l, attr_list);
1073
1074         return 0;
1075
1076 error_device_attr_deinit:
1077         __iio_device_attr_deinit(&iio_attr->dev_attr);
1078 error_iio_dev_attr_free:
1079         kfree(iio_attr);
1080         return ret;
1081 }
1082
1083 static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
1084                                          struct iio_chan_spec const *chan,
1085                                          enum iio_shared_by shared_by,
1086                                          const long *infomask)
1087 {
1088         int i, ret, attrcount = 0;
1089
1090         for_each_set_bit(i, infomask, sizeof(*infomask)*8) {
1091                 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
1092                         return -EINVAL;
1093                 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
1094                                              chan,
1095                                              &iio_read_channel_info,
1096                                              &iio_write_channel_info,
1097                                              i,
1098                                              shared_by,
1099                                              &indio_dev->dev,
1100                                              &indio_dev->channel_attr_list);
1101                 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1102                         continue;
1103                 else if (ret < 0)
1104                         return ret;
1105                 attrcount++;
1106         }
1107
1108         return attrcount;
1109 }
1110
1111 static int iio_device_add_info_mask_type_avail(struct iio_dev *indio_dev,
1112                                                struct iio_chan_spec const *chan,
1113                                                enum iio_shared_by shared_by,
1114                                                const long *infomask)
1115 {
1116         int i, ret, attrcount = 0;
1117         char *avail_postfix;
1118
1119         for_each_set_bit(i, infomask, sizeof(*infomask) * 8) {
1120                 avail_postfix = kasprintf(GFP_KERNEL,
1121                                           "%s_available",
1122                                           iio_chan_info_postfix[i]);
1123                 if (!avail_postfix)
1124                         return -ENOMEM;
1125
1126                 ret = __iio_add_chan_devattr(avail_postfix,
1127                                              chan,
1128                                              &iio_read_channel_info_avail,
1129                                              NULL,
1130                                              i,
1131                                              shared_by,
1132                                              &indio_dev->dev,
1133                                              &indio_dev->channel_attr_list);
1134                 kfree(avail_postfix);
1135                 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1136                         continue;
1137                 else if (ret < 0)
1138                         return ret;
1139                 attrcount++;
1140         }
1141
1142         return attrcount;
1143 }
1144
1145 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
1146                                         struct iio_chan_spec const *chan)
1147 {
1148         int ret, attrcount = 0;
1149         const struct iio_chan_spec_ext_info *ext_info;
1150
1151         if (chan->channel < 0)
1152                 return 0;
1153         ret = iio_device_add_info_mask_type(indio_dev, chan,
1154                                             IIO_SEPARATE,
1155                                             &chan->info_mask_separate);
1156         if (ret < 0)
1157                 return ret;
1158         attrcount += ret;
1159
1160         ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1161                                                   IIO_SEPARATE,
1162                                                   &chan->
1163                                                   info_mask_separate_available);
1164         if (ret < 0)
1165                 return ret;
1166         attrcount += ret;
1167
1168         ret = iio_device_add_info_mask_type(indio_dev, chan,
1169                                             IIO_SHARED_BY_TYPE,
1170                                             &chan->info_mask_shared_by_type);
1171         if (ret < 0)
1172                 return ret;
1173         attrcount += ret;
1174
1175         ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1176                                                   IIO_SHARED_BY_TYPE,
1177                                                   &chan->
1178                                                   info_mask_shared_by_type_available);
1179         if (ret < 0)
1180                 return ret;
1181         attrcount += ret;
1182
1183         ret = iio_device_add_info_mask_type(indio_dev, chan,
1184                                             IIO_SHARED_BY_DIR,
1185                                             &chan->info_mask_shared_by_dir);
1186         if (ret < 0)
1187                 return ret;
1188         attrcount += ret;
1189
1190         ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1191                                                   IIO_SHARED_BY_DIR,
1192                                                   &chan->info_mask_shared_by_dir_available);
1193         if (ret < 0)
1194                 return ret;
1195         attrcount += ret;
1196
1197         ret = iio_device_add_info_mask_type(indio_dev, chan,
1198                                             IIO_SHARED_BY_ALL,
1199                                             &chan->info_mask_shared_by_all);
1200         if (ret < 0)
1201                 return ret;
1202         attrcount += ret;
1203
1204         ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1205                                                   IIO_SHARED_BY_ALL,
1206                                                   &chan->info_mask_shared_by_all_available);
1207         if (ret < 0)
1208                 return ret;
1209         attrcount += ret;
1210
1211         if (chan->ext_info) {
1212                 unsigned int i = 0;
1213                 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
1214                         ret = __iio_add_chan_devattr(ext_info->name,
1215                                         chan,
1216                                         ext_info->read ?
1217                                             &iio_read_channel_ext_info : NULL,
1218                                         ext_info->write ?
1219                                             &iio_write_channel_ext_info : NULL,
1220                                         i,
1221                                         ext_info->shared,
1222                                         &indio_dev->dev,
1223                                         &indio_dev->channel_attr_list);
1224                         i++;
1225                         if (ret == -EBUSY && ext_info->shared)
1226                                 continue;
1227
1228                         if (ret)
1229                                 return ret;
1230
1231                         attrcount++;
1232                 }
1233         }
1234
1235         return attrcount;
1236 }
1237
1238 /**
1239  * iio_free_chan_devattr_list() - Free a list of IIO device attributes
1240  * @attr_list: List of IIO device attributes
1241  *
1242  * This function frees the memory allocated for each of the IIO device
1243  * attributes in the list.
1244  */
1245 void iio_free_chan_devattr_list(struct list_head *attr_list)
1246 {
1247         struct iio_dev_attr *p, *n;
1248
1249         list_for_each_entry_safe(p, n, attr_list, l) {
1250                 kfree(p->dev_attr.attr.name);
1251                 list_del(&p->l);
1252                 kfree(p);
1253         }
1254 }
1255
1256 static ssize_t iio_show_dev_name(struct device *dev,
1257                                  struct device_attribute *attr,
1258                                  char *buf)
1259 {
1260         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1261         return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name);
1262 }
1263
1264 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
1265
1266 static ssize_t iio_show_timestamp_clock(struct device *dev,
1267                                         struct device_attribute *attr,
1268                                         char *buf)
1269 {
1270         const struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1271         const clockid_t clk = iio_device_get_clock(indio_dev);
1272         const char *name;
1273         ssize_t sz;
1274
1275         switch (clk) {
1276         case CLOCK_REALTIME:
1277                 name = "realtime\n";
1278                 sz = sizeof("realtime\n");
1279                 break;
1280         case CLOCK_MONOTONIC:
1281                 name = "monotonic\n";
1282                 sz = sizeof("monotonic\n");
1283                 break;
1284         case CLOCK_MONOTONIC_RAW:
1285                 name = "monotonic_raw\n";
1286                 sz = sizeof("monotonic_raw\n");
1287                 break;
1288         case CLOCK_REALTIME_COARSE:
1289                 name = "realtime_coarse\n";
1290                 sz = sizeof("realtime_coarse\n");
1291                 break;
1292         case CLOCK_MONOTONIC_COARSE:
1293                 name = "monotonic_coarse\n";
1294                 sz = sizeof("monotonic_coarse\n");
1295                 break;
1296         case CLOCK_BOOTTIME:
1297                 name = "boottime\n";
1298                 sz = sizeof("boottime\n");
1299                 break;
1300         case CLOCK_TAI:
1301                 name = "tai\n";
1302                 sz = sizeof("tai\n");
1303                 break;
1304         default:
1305                 BUG();
1306         }
1307
1308         memcpy(buf, name, sz);
1309         return sz;
1310 }
1311
1312 static ssize_t iio_store_timestamp_clock(struct device *dev,
1313                                          struct device_attribute *attr,
1314                                          const char *buf, size_t len)
1315 {
1316         clockid_t clk;
1317         int ret;
1318
1319         if (sysfs_streq(buf, "realtime"))
1320                 clk = CLOCK_REALTIME;
1321         else if (sysfs_streq(buf, "monotonic"))
1322                 clk = CLOCK_MONOTONIC;
1323         else if (sysfs_streq(buf, "monotonic_raw"))
1324                 clk = CLOCK_MONOTONIC_RAW;
1325         else if (sysfs_streq(buf, "realtime_coarse"))
1326                 clk = CLOCK_REALTIME_COARSE;
1327         else if (sysfs_streq(buf, "monotonic_coarse"))
1328                 clk = CLOCK_MONOTONIC_COARSE;
1329         else if (sysfs_streq(buf, "boottime"))
1330                 clk = CLOCK_BOOTTIME;
1331         else if (sysfs_streq(buf, "tai"))
1332                 clk = CLOCK_TAI;
1333         else
1334                 return -EINVAL;
1335
1336         ret = iio_device_set_clock(dev_to_iio_dev(dev), clk);
1337         if (ret)
1338                 return ret;
1339
1340         return len;
1341 }
1342
1343 static DEVICE_ATTR(current_timestamp_clock, S_IRUGO | S_IWUSR,
1344                    iio_show_timestamp_clock, iio_store_timestamp_clock);
1345
1346 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
1347 {
1348         int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
1349         struct iio_dev_attr *p;
1350         struct attribute **attr, *clk = NULL;
1351
1352         /* First count elements in any existing group */
1353         if (indio_dev->info->attrs) {
1354                 attr = indio_dev->info->attrs->attrs;
1355                 while (*attr++ != NULL)
1356                         attrcount_orig++;
1357         }
1358         attrcount = attrcount_orig;
1359         /*
1360          * New channel registration method - relies on the fact a group does
1361          * not need to be initialized if its name is NULL.
1362          */
1363         if (indio_dev->channels)
1364                 for (i = 0; i < indio_dev->num_channels; i++) {
1365                         const struct iio_chan_spec *chan =
1366                                 &indio_dev->channels[i];
1367
1368                         if (chan->type == IIO_TIMESTAMP)
1369                                 clk = &dev_attr_current_timestamp_clock.attr;
1370
1371                         ret = iio_device_add_channel_sysfs(indio_dev, chan);
1372                         if (ret < 0)
1373                                 goto error_clear_attrs;
1374                         attrcount += ret;
1375                 }
1376
1377         if (indio_dev->event_interface)
1378                 clk = &dev_attr_current_timestamp_clock.attr;
1379
1380         if (indio_dev->name)
1381                 attrcount++;
1382         if (clk)
1383                 attrcount++;
1384
1385         indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
1386                                                    sizeof(indio_dev->chan_attr_group.attrs[0]),
1387                                                    GFP_KERNEL);
1388         if (indio_dev->chan_attr_group.attrs == NULL) {
1389                 ret = -ENOMEM;
1390                 goto error_clear_attrs;
1391         }
1392         /* Copy across original attributes */
1393         if (indio_dev->info->attrs)
1394                 memcpy(indio_dev->chan_attr_group.attrs,
1395                        indio_dev->info->attrs->attrs,
1396                        sizeof(indio_dev->chan_attr_group.attrs[0])
1397                        *attrcount_orig);
1398         attrn = attrcount_orig;
1399         /* Add all elements from the list. */
1400         list_for_each_entry(p, &indio_dev->channel_attr_list, l)
1401                 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
1402         if (indio_dev->name)
1403                 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
1404         if (clk)
1405                 indio_dev->chan_attr_group.attrs[attrn++] = clk;
1406
1407         indio_dev->groups[indio_dev->groupcounter++] =
1408                 &indio_dev->chan_attr_group;
1409
1410         return 0;
1411
1412 error_clear_attrs:
1413         iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1414
1415         return ret;
1416 }
1417
1418 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
1419 {
1420
1421         iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1422         kfree(indio_dev->chan_attr_group.attrs);
1423         indio_dev->chan_attr_group.attrs = NULL;
1424 }
1425
1426 static void iio_dev_release(struct device *device)
1427 {
1428         struct iio_dev *indio_dev = dev_to_iio_dev(device);
1429         if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1430                 iio_device_unregister_trigger_consumer(indio_dev);
1431         iio_device_unregister_eventset(indio_dev);
1432         iio_device_unregister_sysfs(indio_dev);
1433
1434         iio_buffer_put(indio_dev->buffer);
1435
1436         ida_simple_remove(&iio_ida, indio_dev->id);
1437         kfree(indio_dev);
1438 }
1439
1440 struct device_type iio_device_type = {
1441         .name = "iio_device",
1442         .release = iio_dev_release,
1443 };
1444
1445 /**
1446  * iio_device_alloc() - allocate an iio_dev from a driver
1447  * @sizeof_priv:        Space to allocate for private structure.
1448  **/
1449 struct iio_dev *iio_device_alloc(int sizeof_priv)
1450 {
1451         struct iio_dev *dev;
1452         size_t alloc_size;
1453
1454         alloc_size = sizeof(struct iio_dev);
1455         if (sizeof_priv) {
1456                 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
1457                 alloc_size += sizeof_priv;
1458         }
1459         /* ensure 32-byte alignment of whole construct ? */
1460         alloc_size += IIO_ALIGN - 1;
1461
1462         dev = kzalloc(alloc_size, GFP_KERNEL);
1463
1464         if (dev) {
1465                 dev->dev.groups = dev->groups;
1466                 dev->dev.type = &iio_device_type;
1467                 dev->dev.bus = &iio_bus_type;
1468                 device_initialize(&dev->dev);
1469                 dev_set_drvdata(&dev->dev, (void *)dev);
1470                 mutex_init(&dev->mlock);
1471                 mutex_init(&dev->info_exist_lock);
1472                 INIT_LIST_HEAD(&dev->channel_attr_list);
1473
1474                 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
1475                 if (dev->id < 0) {
1476                         /* cannot use a dev_err as the name isn't available */
1477                         pr_err("failed to get device id\n");
1478                         kfree(dev);
1479                         return NULL;
1480                 }
1481                 dev_set_name(&dev->dev, "iio:device%d", dev->id);
1482                 INIT_LIST_HEAD(&dev->buffer_list);
1483         }
1484
1485         return dev;
1486 }
1487 EXPORT_SYMBOL(iio_device_alloc);
1488
1489 /**
1490  * iio_device_free() - free an iio_dev from a driver
1491  * @dev:                the iio_dev associated with the device
1492  **/
1493 void iio_device_free(struct iio_dev *dev)
1494 {
1495         if (dev)
1496                 put_device(&dev->dev);
1497 }
1498 EXPORT_SYMBOL(iio_device_free);
1499
1500 static void devm_iio_device_release(struct device *dev, void *res)
1501 {
1502         iio_device_free(*(struct iio_dev **)res);
1503 }
1504
1505 int devm_iio_device_match(struct device *dev, void *res, void *data)
1506 {
1507         struct iio_dev **r = res;
1508         if (!r || !*r) {
1509                 WARN_ON(!r || !*r);
1510                 return 0;
1511         }
1512         return *r == data;
1513 }
1514 EXPORT_SYMBOL_GPL(devm_iio_device_match);
1515
1516 /**
1517  * devm_iio_device_alloc - Resource-managed iio_device_alloc()
1518  * @dev:                Device to allocate iio_dev for
1519  * @sizeof_priv:        Space to allocate for private structure.
1520  *
1521  * Managed iio_device_alloc. iio_dev allocated with this function is
1522  * automatically freed on driver detach.
1523  *
1524  * If an iio_dev allocated with this function needs to be freed separately,
1525  * devm_iio_device_free() must be used.
1526  *
1527  * RETURNS:
1528  * Pointer to allocated iio_dev on success, NULL on failure.
1529  */
1530 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)
1531 {
1532         struct iio_dev **ptr, *iio_dev;
1533
1534         ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),
1535                            GFP_KERNEL);
1536         if (!ptr)
1537                 return NULL;
1538
1539         iio_dev = iio_device_alloc(sizeof_priv);
1540         if (iio_dev) {
1541                 *ptr = iio_dev;
1542                 devres_add(dev, ptr);
1543         } else {
1544                 devres_free(ptr);
1545         }
1546
1547         return iio_dev;
1548 }
1549 EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
1550
1551 /**
1552  * devm_iio_device_free - Resource-managed iio_device_free()
1553  * @dev:                Device this iio_dev belongs to
1554  * @iio_dev:            the iio_dev associated with the device
1555  *
1556  * Free iio_dev allocated with devm_iio_device_alloc().
1557  */
1558 void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev)
1559 {
1560         int rc;
1561
1562         rc = devres_release(dev, devm_iio_device_release,
1563                             devm_iio_device_match, iio_dev);
1564         WARN_ON(rc);
1565 }
1566 EXPORT_SYMBOL_GPL(devm_iio_device_free);
1567
1568 /**
1569  * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1570  * @inode:      Inode structure for identifying the device in the file system
1571  * @filp:       File structure for iio device used to keep and later access
1572  *              private data
1573  *
1574  * Return: 0 on success or -EBUSY if the device is already opened
1575  **/
1576 static int iio_chrdev_open(struct inode *inode, struct file *filp)
1577 {
1578         struct iio_dev *indio_dev = container_of(inode->i_cdev,
1579                                                 struct iio_dev, chrdev);
1580
1581         if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
1582                 return -EBUSY;
1583
1584         iio_device_get(indio_dev);
1585
1586         filp->private_data = indio_dev;
1587
1588         return 0;
1589 }
1590
1591 /**
1592  * iio_chrdev_release() - chrdev file close buffer access and ioctls
1593  * @inode:      Inode structure pointer for the char device
1594  * @filp:       File structure pointer for the char device
1595  *
1596  * Return: 0 for successful release
1597  */
1598 static int iio_chrdev_release(struct inode *inode, struct file *filp)
1599 {
1600         struct iio_dev *indio_dev = container_of(inode->i_cdev,
1601                                                 struct iio_dev, chrdev);
1602         clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
1603         iio_device_put(indio_dev);
1604
1605         return 0;
1606 }
1607
1608 /* Somewhat of a cross file organization violation - ioctls here are actually
1609  * event related */
1610 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1611 {
1612         struct iio_dev *indio_dev = filp->private_data;
1613         int __user *ip = (int __user *)arg;
1614         int fd;
1615
1616         if (!indio_dev->info)
1617                 return -ENODEV;
1618
1619         if (cmd == IIO_GET_EVENT_FD_IOCTL) {
1620                 fd = iio_event_getfd(indio_dev);
1621                 if (fd < 0)
1622                         return fd;
1623                 if (copy_to_user(ip, &fd, sizeof(fd)))
1624                         return -EFAULT;
1625                 return 0;
1626         }
1627         return -EINVAL;
1628 }
1629
1630 static const struct file_operations iio_buffer_fileops = {
1631         .read = iio_buffer_read_first_n_outer_addr,
1632         .release = iio_chrdev_release,
1633         .open = iio_chrdev_open,
1634         .poll = iio_buffer_poll_addr,
1635         .owner = THIS_MODULE,
1636         .llseek = noop_llseek,
1637         .unlocked_ioctl = iio_ioctl,
1638         .compat_ioctl = iio_ioctl,
1639 };
1640
1641 static int iio_check_unique_scan_index(struct iio_dev *indio_dev)
1642 {
1643         int i, j;
1644         const struct iio_chan_spec *channels = indio_dev->channels;
1645
1646         if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))
1647                 return 0;
1648
1649         for (i = 0; i < indio_dev->num_channels - 1; i++) {
1650                 if (channels[i].scan_index < 0)
1651                         continue;
1652                 for (j = i + 1; j < indio_dev->num_channels; j++)
1653                         if (channels[i].scan_index == channels[j].scan_index) {
1654                                 dev_err(&indio_dev->dev,
1655                                         "Duplicate scan index %d\n",
1656                                         channels[i].scan_index);
1657                                 return -EINVAL;
1658                         }
1659         }
1660
1661         return 0;
1662 }
1663
1664 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
1665
1666 int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
1667 {
1668         int ret;
1669
1670         indio_dev->driver_module = this_mod;
1671         /* If the calling driver did not initialize of_node, do it here */
1672         if (!indio_dev->dev.of_node && indio_dev->dev.parent)
1673                 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
1674
1675         ret = iio_check_unique_scan_index(indio_dev);
1676         if (ret < 0)
1677                 return ret;
1678
1679         if (!indio_dev->info)
1680                 return -EINVAL;
1681
1682         /* configure elements for the chrdev */
1683         indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
1684
1685         ret = iio_device_register_debugfs(indio_dev);
1686         if (ret) {
1687                 dev_err(indio_dev->dev.parent,
1688                         "Failed to register debugfs interfaces\n");
1689                 return ret;
1690         }
1691
1692         ret = iio_buffer_alloc_sysfs_and_mask(indio_dev);
1693         if (ret) {
1694                 dev_err(indio_dev->dev.parent,
1695                         "Failed to create buffer sysfs interfaces\n");
1696                 goto error_unreg_debugfs;
1697         }
1698
1699         ret = iio_device_register_sysfs(indio_dev);
1700         if (ret) {
1701                 dev_err(indio_dev->dev.parent,
1702                         "Failed to register sysfs interfaces\n");
1703                 goto error_buffer_free_sysfs;
1704         }
1705         ret = iio_device_register_eventset(indio_dev);
1706         if (ret) {
1707                 dev_err(indio_dev->dev.parent,
1708                         "Failed to register event set\n");
1709                 goto error_free_sysfs;
1710         }
1711         if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1712                 iio_device_register_trigger_consumer(indio_dev);
1713
1714         if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1715                 indio_dev->setup_ops == NULL)
1716                 indio_dev->setup_ops = &noop_ring_setup_ops;
1717
1718         cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1719
1720         indio_dev->chrdev.owner = this_mod;
1721
1722         ret = cdev_device_add(&indio_dev->chrdev, &indio_dev->dev);
1723         if (ret < 0)
1724                 goto error_unreg_eventset;
1725
1726         return 0;
1727
1728 error_unreg_eventset:
1729         iio_device_unregister_eventset(indio_dev);
1730 error_free_sysfs:
1731         iio_device_unregister_sysfs(indio_dev);
1732 error_buffer_free_sysfs:
1733         iio_buffer_free_sysfs_and_mask(indio_dev);
1734 error_unreg_debugfs:
1735         iio_device_unregister_debugfs(indio_dev);
1736         return ret;
1737 }
1738 EXPORT_SYMBOL(__iio_device_register);
1739
1740 /**
1741  * iio_device_unregister() - unregister a device from the IIO subsystem
1742  * @indio_dev:          Device structure representing the device.
1743  **/
1744 void iio_device_unregister(struct iio_dev *indio_dev)
1745 {
1746         cdev_device_del(&indio_dev->chrdev, &indio_dev->dev);
1747
1748         mutex_lock(&indio_dev->info_exist_lock);
1749
1750         iio_device_unregister_debugfs(indio_dev);
1751
1752         iio_disable_all_buffers(indio_dev);
1753
1754         indio_dev->info = NULL;
1755
1756         iio_device_wakeup_eventset(indio_dev);
1757         iio_buffer_wakeup_poll(indio_dev);
1758
1759         mutex_unlock(&indio_dev->info_exist_lock);
1760
1761         iio_buffer_free_sysfs_and_mask(indio_dev);
1762 }
1763 EXPORT_SYMBOL(iio_device_unregister);
1764
1765 static void devm_iio_device_unreg(struct device *dev, void *res)
1766 {
1767         iio_device_unregister(*(struct iio_dev **)res);
1768 }
1769
1770 int __devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev,
1771                                struct module *this_mod)
1772 {
1773         struct iio_dev **ptr;
1774         int ret;
1775
1776         ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL);
1777         if (!ptr)
1778                 return -ENOMEM;
1779
1780         *ptr = indio_dev;
1781         ret = __iio_device_register(indio_dev, this_mod);
1782         if (!ret)
1783                 devres_add(dev, ptr);
1784         else
1785                 devres_free(ptr);
1786
1787         return ret;
1788 }
1789 EXPORT_SYMBOL_GPL(__devm_iio_device_register);
1790
1791 /**
1792  * devm_iio_device_unregister - Resource-managed iio_device_unregister()
1793  * @dev:        Device this iio_dev belongs to
1794  * @indio_dev:  the iio_dev associated with the device
1795  *
1796  * Unregister iio_dev registered with devm_iio_device_register().
1797  */
1798 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev)
1799 {
1800         int rc;
1801
1802         rc = devres_release(dev, devm_iio_device_unreg,
1803                             devm_iio_device_match, indio_dev);
1804         WARN_ON(rc);
1805 }
1806 EXPORT_SYMBOL_GPL(devm_iio_device_unregister);
1807
1808 /**
1809  * iio_device_claim_direct_mode - Keep device in direct mode
1810  * @indio_dev:  the iio_dev associated with the device
1811  *
1812  * If the device is in direct mode it is guaranteed to stay
1813  * that way until iio_device_release_direct_mode() is called.
1814  *
1815  * Use with iio_device_release_direct_mode()
1816  *
1817  * Returns: 0 on success, -EBUSY on failure
1818  */
1819 int iio_device_claim_direct_mode(struct iio_dev *indio_dev)
1820 {
1821         mutex_lock(&indio_dev->mlock);
1822
1823         if (iio_buffer_enabled(indio_dev)) {
1824                 mutex_unlock(&indio_dev->mlock);
1825                 return -EBUSY;
1826         }
1827         return 0;
1828 }
1829 EXPORT_SYMBOL_GPL(iio_device_claim_direct_mode);
1830
1831 /**
1832  * iio_device_release_direct_mode - releases claim on direct mode
1833  * @indio_dev:  the iio_dev associated with the device
1834  *
1835  * Release the claim. Device is no longer guaranteed to stay
1836  * in direct mode.
1837  *
1838  * Use with iio_device_claim_direct_mode()
1839  */
1840 void iio_device_release_direct_mode(struct iio_dev *indio_dev)
1841 {
1842         mutex_unlock(&indio_dev->mlock);
1843 }
1844 EXPORT_SYMBOL_GPL(iio_device_release_direct_mode);
1845
1846 subsys_initcall(iio_init);
1847 module_exit(iio_exit);
1848
1849 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1850 MODULE_DESCRIPTION("Industrial I/O core");
1851 MODULE_LICENSE("GPL");