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/iio/iio.h> 29 #include "iio_core.h" 30 #include "iio_core_trigger.h" 31 #include <linux/iio/sysfs.h> 32 #include <linux/iio/events.h> 33 #include <linux/iio/buffer.h> 34 35 /* IDA to assign each registered device a unique id */ 36 static DEFINE_IDA(iio_ida); 37 38 static dev_t iio_devt; 39 40 #define IIO_DEV_MAX 256 41 struct bus_type iio_bus_type = { 42 .name = "iio", 43 }; 44 EXPORT_SYMBOL(iio_bus_type); 45 46 static struct dentry *iio_debugfs_dentry; 47 48 static const char * const iio_direction[] = { 49 [0] = "in", 50 [1] = "out", 51 }; 52 53 static const char * const iio_chan_type_name_spec[] = { 54 [IIO_VOLTAGE] = "voltage", 55 [IIO_CURRENT] = "current", 56 [IIO_POWER] = "power", 57 [IIO_ACCEL] = "accel", 58 [IIO_ANGL_VEL] = "anglvel", 59 [IIO_MAGN] = "magn", 60 [IIO_LIGHT] = "illuminance", 61 [IIO_INTENSITY] = "intensity", 62 [IIO_PROXIMITY] = "proximity", 63 [IIO_TEMP] = "temp", 64 [IIO_INCLI] = "incli", 65 [IIO_ROT] = "rot", 66 [IIO_ANGL] = "angl", 67 [IIO_TIMESTAMP] = "timestamp", 68 [IIO_CAPACITANCE] = "capacitance", 69 [IIO_ALTVOLTAGE] = "altvoltage", 70 [IIO_CCT] = "cct", 71 [IIO_PRESSURE] = "pressure", 72 [IIO_HUMIDITYRELATIVE] = "humidityrelative", 73 }; 74 75 static const char * const iio_modifier_names[] = { 76 [IIO_MOD_X] = "x", 77 [IIO_MOD_Y] = "y", 78 [IIO_MOD_Z] = "z", 79 [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)", 80 [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2", 81 [IIO_MOD_LIGHT_BOTH] = "both", 82 [IIO_MOD_LIGHT_IR] = "ir", 83 [IIO_MOD_LIGHT_CLEAR] = "clear", 84 [IIO_MOD_LIGHT_RED] = "red", 85 [IIO_MOD_LIGHT_GREEN] = "green", 86 [IIO_MOD_LIGHT_BLUE] = "blue", 87 [IIO_MOD_QUATERNION] = "quaternion", 88 [IIO_MOD_TEMP_AMBIENT] = "ambient", 89 [IIO_MOD_TEMP_OBJECT] = "object", 90 [IIO_MOD_NORTH_MAGN] = "from_north_magnetic", 91 [IIO_MOD_NORTH_TRUE] = "from_north_true", 92 [IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp", 93 [IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp", 94 }; 95 96 /* relies on pairs of these shared then separate */ 97 static const char * const iio_chan_info_postfix[] = { 98 [IIO_CHAN_INFO_RAW] = "raw", 99 [IIO_CHAN_INFO_PROCESSED] = "input", 100 [IIO_CHAN_INFO_SCALE] = "scale", 101 [IIO_CHAN_INFO_OFFSET] = "offset", 102 [IIO_CHAN_INFO_CALIBSCALE] = "calibscale", 103 [IIO_CHAN_INFO_CALIBBIAS] = "calibbias", 104 [IIO_CHAN_INFO_PEAK] = "peak_raw", 105 [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale", 106 [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw", 107 [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw", 108 [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY] 109 = "filter_low_pass_3db_frequency", 110 [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency", 111 [IIO_CHAN_INFO_FREQUENCY] = "frequency", 112 [IIO_CHAN_INFO_PHASE] = "phase", 113 [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain", 114 [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis", 115 [IIO_CHAN_INFO_INT_TIME] = "integration_time", 116 }; 117 118 /** 119 * iio_find_channel_from_si() - get channel from its scan index 120 * @indio_dev: device 121 * @si: scan index to match 122 */ 123 const struct iio_chan_spec 124 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si) 125 { 126 int i; 127 128 for (i = 0; i < indio_dev->num_channels; i++) 129 if (indio_dev->channels[i].scan_index == si) 130 return &indio_dev->channels[i]; 131 return NULL; 132 } 133 134 /* This turns up an awful lot */ 135 ssize_t iio_read_const_attr(struct device *dev, 136 struct device_attribute *attr, 137 char *buf) 138 { 139 return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string); 140 } 141 EXPORT_SYMBOL(iio_read_const_attr); 142 143 static int __init iio_init(void) 144 { 145 int ret; 146 147 /* Register sysfs bus */ 148 ret = bus_register(&iio_bus_type); 149 if (ret < 0) { 150 pr_err("could not register bus type\n"); 151 goto error_nothing; 152 } 153 154 ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio"); 155 if (ret < 0) { 156 pr_err("failed to allocate char dev region\n"); 157 goto error_unregister_bus_type; 158 } 159 160 iio_debugfs_dentry = debugfs_create_dir("iio", NULL); 161 162 return 0; 163 164 error_unregister_bus_type: 165 bus_unregister(&iio_bus_type); 166 error_nothing: 167 return ret; 168 } 169 170 static void __exit iio_exit(void) 171 { 172 if (iio_devt) 173 unregister_chrdev_region(iio_devt, IIO_DEV_MAX); 174 bus_unregister(&iio_bus_type); 175 debugfs_remove(iio_debugfs_dentry); 176 } 177 178 #if defined(CONFIG_DEBUG_FS) 179 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf, 180 size_t count, loff_t *ppos) 181 { 182 struct iio_dev *indio_dev = file->private_data; 183 char buf[20]; 184 unsigned val = 0; 185 ssize_t len; 186 int ret; 187 188 ret = indio_dev->info->debugfs_reg_access(indio_dev, 189 indio_dev->cached_reg_addr, 190 0, &val); 191 if (ret) 192 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__); 193 194 len = snprintf(buf, sizeof(buf), "0x%X\n", val); 195 196 return simple_read_from_buffer(userbuf, count, ppos, buf, len); 197 } 198 199 static ssize_t iio_debugfs_write_reg(struct file *file, 200 const char __user *userbuf, size_t count, loff_t *ppos) 201 { 202 struct iio_dev *indio_dev = file->private_data; 203 unsigned reg, val; 204 char buf[80]; 205 int ret; 206 207 count = min_t(size_t, count, (sizeof(buf)-1)); 208 if (copy_from_user(buf, userbuf, count)) 209 return -EFAULT; 210 211 buf[count] = 0; 212 213 ret = sscanf(buf, "%i %i", ®, &val); 214 215 switch (ret) { 216 case 1: 217 indio_dev->cached_reg_addr = reg; 218 break; 219 case 2: 220 indio_dev->cached_reg_addr = reg; 221 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg, 222 val, NULL); 223 if (ret) { 224 dev_err(indio_dev->dev.parent, "%s: write failed\n", 225 __func__); 226 return ret; 227 } 228 break; 229 default: 230 return -EINVAL; 231 } 232 233 return count; 234 } 235 236 static const struct file_operations iio_debugfs_reg_fops = { 237 .open = simple_open, 238 .read = iio_debugfs_read_reg, 239 .write = iio_debugfs_write_reg, 240 }; 241 242 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev) 243 { 244 debugfs_remove_recursive(indio_dev->debugfs_dentry); 245 } 246 247 static int iio_device_register_debugfs(struct iio_dev *indio_dev) 248 { 249 struct dentry *d; 250 251 if (indio_dev->info->debugfs_reg_access == NULL) 252 return 0; 253 254 if (!iio_debugfs_dentry) 255 return 0; 256 257 indio_dev->debugfs_dentry = 258 debugfs_create_dir(dev_name(&indio_dev->dev), 259 iio_debugfs_dentry); 260 if (indio_dev->debugfs_dentry == NULL) { 261 dev_warn(indio_dev->dev.parent, 262 "Failed to create debugfs directory\n"); 263 return -EFAULT; 264 } 265 266 d = debugfs_create_file("direct_reg_access", 0644, 267 indio_dev->debugfs_dentry, 268 indio_dev, &iio_debugfs_reg_fops); 269 if (!d) { 270 iio_device_unregister_debugfs(indio_dev); 271 return -ENOMEM; 272 } 273 274 return 0; 275 } 276 #else 277 static int iio_device_register_debugfs(struct iio_dev *indio_dev) 278 { 279 return 0; 280 } 281 282 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev) 283 { 284 } 285 #endif /* CONFIG_DEBUG_FS */ 286 287 static ssize_t iio_read_channel_ext_info(struct device *dev, 288 struct device_attribute *attr, 289 char *buf) 290 { 291 struct iio_dev *indio_dev = dev_to_iio_dev(dev); 292 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); 293 const struct iio_chan_spec_ext_info *ext_info; 294 295 ext_info = &this_attr->c->ext_info[this_attr->address]; 296 297 return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf); 298 } 299 300 static ssize_t iio_write_channel_ext_info(struct device *dev, 301 struct device_attribute *attr, 302 const char *buf, 303 size_t len) 304 { 305 struct iio_dev *indio_dev = dev_to_iio_dev(dev); 306 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); 307 const struct iio_chan_spec_ext_info *ext_info; 308 309 ext_info = &this_attr->c->ext_info[this_attr->address]; 310 311 return ext_info->write(indio_dev, ext_info->private, 312 this_attr->c, buf, len); 313 } 314 315 ssize_t iio_enum_available_read(struct iio_dev *indio_dev, 316 uintptr_t priv, const struct iio_chan_spec *chan, char *buf) 317 { 318 const struct iio_enum *e = (const struct iio_enum *)priv; 319 unsigned int i; 320 size_t len = 0; 321 322 if (!e->num_items) 323 return 0; 324 325 for (i = 0; i < e->num_items; ++i) 326 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]); 327 328 /* replace last space with a newline */ 329 buf[len - 1] = '\n'; 330 331 return len; 332 } 333 EXPORT_SYMBOL_GPL(iio_enum_available_read); 334 335 ssize_t iio_enum_read(struct iio_dev *indio_dev, 336 uintptr_t priv, const struct iio_chan_spec *chan, char *buf) 337 { 338 const struct iio_enum *e = (const struct iio_enum *)priv; 339 int i; 340 341 if (!e->get) 342 return -EINVAL; 343 344 i = e->get(indio_dev, chan); 345 if (i < 0) 346 return i; 347 else if (i >= e->num_items) 348 return -EINVAL; 349 350 return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]); 351 } 352 EXPORT_SYMBOL_GPL(iio_enum_read); 353 354 ssize_t iio_enum_write(struct iio_dev *indio_dev, 355 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf, 356 size_t len) 357 { 358 const struct iio_enum *e = (const struct iio_enum *)priv; 359 unsigned int i; 360 int ret; 361 362 if (!e->set) 363 return -EINVAL; 364 365 for (i = 0; i < e->num_items; i++) { 366 if (sysfs_streq(buf, e->items[i])) 367 break; 368 } 369 370 if (i == e->num_items) 371 return -EINVAL; 372 373 ret = e->set(indio_dev, chan, i); 374 return ret ? ret : len; 375 } 376 EXPORT_SYMBOL_GPL(iio_enum_write); 377 378 /** 379 * iio_format_value() - Formats a IIO value into its string representation 380 * @buf: The buffer to which the formated value gets written 381 * @type: One of the IIO_VAL_... constants. This decides how the val and val2 382 * parameters are formatted. 383 * @vals: pointer to the values, exact meaning depends on the type parameter. 384 */ 385 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals) 386 { 387 unsigned long long tmp; 388 bool scale_db = false; 389 390 switch (type) { 391 case IIO_VAL_INT: 392 return sprintf(buf, "%d\n", vals[0]); 393 case IIO_VAL_INT_PLUS_MICRO_DB: 394 scale_db = true; 395 case IIO_VAL_INT_PLUS_MICRO: 396 if (vals[1] < 0) 397 return sprintf(buf, "-%ld.%06u%s\n", abs(vals[0]), 398 -vals[1], 399 scale_db ? " dB" : ""); 400 else 401 return sprintf(buf, "%d.%06u%s\n", vals[0], vals[1], 402 scale_db ? " dB" : ""); 403 case IIO_VAL_INT_PLUS_NANO: 404 if (vals[1] < 0) 405 return sprintf(buf, "-%ld.%09u\n", abs(vals[0]), 406 -vals[1]); 407 else 408 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]); 409 case IIO_VAL_FRACTIONAL: 410 tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]); 411 vals[1] = do_div(tmp, 1000000000LL); 412 vals[0] = tmp; 413 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]); 414 case IIO_VAL_FRACTIONAL_LOG2: 415 tmp = (s64)vals[0] * 1000000000LL >> vals[1]; 416 vals[1] = do_div(tmp, 1000000000LL); 417 vals[0] = tmp; 418 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]); 419 case IIO_VAL_INT_MULTIPLE: 420 { 421 int i; 422 int len = 0; 423 424 for (i = 0; i < size; ++i) 425 len += snprintf(&buf[len], PAGE_SIZE - len, "%d ", 426 vals[i]); 427 len += snprintf(&buf[len], PAGE_SIZE - len, "\n"); 428 return len; 429 } 430 default: 431 return 0; 432 } 433 } 434 435 static ssize_t iio_read_channel_info(struct device *dev, 436 struct device_attribute *attr, 437 char *buf) 438 { 439 struct iio_dev *indio_dev = dev_to_iio_dev(dev); 440 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); 441 int vals[INDIO_MAX_RAW_ELEMENTS]; 442 int ret; 443 int val_len = 2; 444 445 if (indio_dev->info->read_raw_multi) 446 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c, 447 INDIO_MAX_RAW_ELEMENTS, 448 vals, &val_len, 449 this_attr->address); 450 else 451 ret = indio_dev->info->read_raw(indio_dev, this_attr->c, 452 &vals[0], &vals[1], this_attr->address); 453 454 if (ret < 0) 455 return ret; 456 457 return iio_format_value(buf, ret, val_len, vals); 458 } 459 460 /** 461 * iio_str_to_fixpoint() - Parse a fixed-point number from a string 462 * @str: The string to parse 463 * @fract_mult: Multiplier for the first decimal place, should be a power of 10 464 * @integer: The integer part of the number 465 * @fract: The fractional part of the number 466 * 467 * Returns 0 on success, or a negative error code if the string could not be 468 * parsed. 469 */ 470 int iio_str_to_fixpoint(const char *str, int fract_mult, 471 int *integer, int *fract) 472 { 473 int i = 0, f = 0; 474 bool integer_part = true, negative = false; 475 476 if (str[0] == '-') { 477 negative = true; 478 str++; 479 } else if (str[0] == '+') { 480 str++; 481 } 482 483 while (*str) { 484 if ('0' <= *str && *str <= '9') { 485 if (integer_part) { 486 i = i * 10 + *str - '0'; 487 } else { 488 f += fract_mult * (*str - '0'); 489 fract_mult /= 10; 490 } 491 } else if (*str == '\n') { 492 if (*(str + 1) == '\0') 493 break; 494 else 495 return -EINVAL; 496 } else if (*str == '.' && integer_part) { 497 integer_part = false; 498 } else { 499 return -EINVAL; 500 } 501 str++; 502 } 503 504 if (negative) { 505 if (i) 506 i = -i; 507 else 508 f = -f; 509 } 510 511 *integer = i; 512 *fract = f; 513 514 return 0; 515 } 516 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint); 517 518 static ssize_t iio_write_channel_info(struct device *dev, 519 struct device_attribute *attr, 520 const char *buf, 521 size_t len) 522 { 523 struct iio_dev *indio_dev = dev_to_iio_dev(dev); 524 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); 525 int ret, fract_mult = 100000; 526 int integer, fract; 527 528 /* Assumes decimal - precision based on number of digits */ 529 if (!indio_dev->info->write_raw) 530 return -EINVAL; 531 532 if (indio_dev->info->write_raw_get_fmt) 533 switch (indio_dev->info->write_raw_get_fmt(indio_dev, 534 this_attr->c, this_attr->address)) { 535 case IIO_VAL_INT_PLUS_MICRO: 536 fract_mult = 100000; 537 break; 538 case IIO_VAL_INT_PLUS_NANO: 539 fract_mult = 100000000; 540 break; 541 default: 542 return -EINVAL; 543 } 544 545 ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract); 546 if (ret) 547 return ret; 548 549 ret = indio_dev->info->write_raw(indio_dev, this_attr->c, 550 integer, fract, this_attr->address); 551 if (ret) 552 return ret; 553 554 return len; 555 } 556 557 static 558 int __iio_device_attr_init(struct device_attribute *dev_attr, 559 const char *postfix, 560 struct iio_chan_spec const *chan, 561 ssize_t (*readfunc)(struct device *dev, 562 struct device_attribute *attr, 563 char *buf), 564 ssize_t (*writefunc)(struct device *dev, 565 struct device_attribute *attr, 566 const char *buf, 567 size_t len), 568 enum iio_shared_by shared_by) 569 { 570 int ret = 0; 571 char *name = NULL; 572 char *full_postfix; 573 sysfs_attr_init(&dev_attr->attr); 574 575 /* Build up postfix of <extend_name>_<modifier>_postfix */ 576 if (chan->modified && (shared_by == IIO_SEPARATE)) { 577 if (chan->extend_name) 578 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s", 579 iio_modifier_names[chan 580 ->channel2], 581 chan->extend_name, 582 postfix); 583 else 584 full_postfix = kasprintf(GFP_KERNEL, "%s_%s", 585 iio_modifier_names[chan 586 ->channel2], 587 postfix); 588 } else { 589 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE) 590 full_postfix = kstrdup(postfix, GFP_KERNEL); 591 else 592 full_postfix = kasprintf(GFP_KERNEL, 593 "%s_%s", 594 chan->extend_name, 595 postfix); 596 } 597 if (full_postfix == NULL) 598 return -ENOMEM; 599 600 if (chan->differential) { /* Differential can not have modifier */ 601 switch (shared_by) { 602 case IIO_SHARED_BY_ALL: 603 name = kasprintf(GFP_KERNEL, "%s", full_postfix); 604 break; 605 case IIO_SHARED_BY_DIR: 606 name = kasprintf(GFP_KERNEL, "%s_%s", 607 iio_direction[chan->output], 608 full_postfix); 609 break; 610 case IIO_SHARED_BY_TYPE: 611 name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s", 612 iio_direction[chan->output], 613 iio_chan_type_name_spec[chan->type], 614 iio_chan_type_name_spec[chan->type], 615 full_postfix); 616 break; 617 case IIO_SEPARATE: 618 if (!chan->indexed) { 619 WARN_ON("Differential channels must be indexed\n"); 620 ret = -EINVAL; 621 goto error_free_full_postfix; 622 } 623 name = kasprintf(GFP_KERNEL, 624 "%s_%s%d-%s%d_%s", 625 iio_direction[chan->output], 626 iio_chan_type_name_spec[chan->type], 627 chan->channel, 628 iio_chan_type_name_spec[chan->type], 629 chan->channel2, 630 full_postfix); 631 break; 632 } 633 } else { /* Single ended */ 634 switch (shared_by) { 635 case IIO_SHARED_BY_ALL: 636 name = kasprintf(GFP_KERNEL, "%s", full_postfix); 637 break; 638 case IIO_SHARED_BY_DIR: 639 name = kasprintf(GFP_KERNEL, "%s_%s", 640 iio_direction[chan->output], 641 full_postfix); 642 break; 643 case IIO_SHARED_BY_TYPE: 644 name = kasprintf(GFP_KERNEL, "%s_%s_%s", 645 iio_direction[chan->output], 646 iio_chan_type_name_spec[chan->type], 647 full_postfix); 648 break; 649 650 case IIO_SEPARATE: 651 if (chan->indexed) 652 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s", 653 iio_direction[chan->output], 654 iio_chan_type_name_spec[chan->type], 655 chan->channel, 656 full_postfix); 657 else 658 name = kasprintf(GFP_KERNEL, "%s_%s_%s", 659 iio_direction[chan->output], 660 iio_chan_type_name_spec[chan->type], 661 full_postfix); 662 break; 663 } 664 } 665 if (name == NULL) { 666 ret = -ENOMEM; 667 goto error_free_full_postfix; 668 } 669 dev_attr->attr.name = name; 670 671 if (readfunc) { 672 dev_attr->attr.mode |= S_IRUGO; 673 dev_attr->show = readfunc; 674 } 675 676 if (writefunc) { 677 dev_attr->attr.mode |= S_IWUSR; 678 dev_attr->store = writefunc; 679 } 680 681 error_free_full_postfix: 682 kfree(full_postfix); 683 684 return ret; 685 } 686 687 static void __iio_device_attr_deinit(struct device_attribute *dev_attr) 688 { 689 kfree(dev_attr->attr.name); 690 } 691 692 int __iio_add_chan_devattr(const char *postfix, 693 struct iio_chan_spec const *chan, 694 ssize_t (*readfunc)(struct device *dev, 695 struct device_attribute *attr, 696 char *buf), 697 ssize_t (*writefunc)(struct device *dev, 698 struct device_attribute *attr, 699 const char *buf, 700 size_t len), 701 u64 mask, 702 enum iio_shared_by shared_by, 703 struct device *dev, 704 struct list_head *attr_list) 705 { 706 int ret; 707 struct iio_dev_attr *iio_attr, *t; 708 709 iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL); 710 if (iio_attr == NULL) 711 return -ENOMEM; 712 ret = __iio_device_attr_init(&iio_attr->dev_attr, 713 postfix, chan, 714 readfunc, writefunc, shared_by); 715 if (ret) 716 goto error_iio_dev_attr_free; 717 iio_attr->c = chan; 718 iio_attr->address = mask; 719 list_for_each_entry(t, attr_list, l) 720 if (strcmp(t->dev_attr.attr.name, 721 iio_attr->dev_attr.attr.name) == 0) { 722 if (shared_by == IIO_SEPARATE) 723 dev_err(dev, "tried to double register : %s\n", 724 t->dev_attr.attr.name); 725 ret = -EBUSY; 726 goto error_device_attr_deinit; 727 } 728 list_add(&iio_attr->l, attr_list); 729 730 return 0; 731 732 error_device_attr_deinit: 733 __iio_device_attr_deinit(&iio_attr->dev_attr); 734 error_iio_dev_attr_free: 735 kfree(iio_attr); 736 return ret; 737 } 738 739 static int iio_device_add_info_mask_type(struct iio_dev *indio_dev, 740 struct iio_chan_spec const *chan, 741 enum iio_shared_by shared_by, 742 const long *infomask) 743 { 744 int i, ret, attrcount = 0; 745 746 for_each_set_bit(i, infomask, sizeof(infomask)*8) { 747 if (i >= ARRAY_SIZE(iio_chan_info_postfix)) 748 return -EINVAL; 749 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i], 750 chan, 751 &iio_read_channel_info, 752 &iio_write_channel_info, 753 i, 754 shared_by, 755 &indio_dev->dev, 756 &indio_dev->channel_attr_list); 757 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE)) 758 continue; 759 else if (ret < 0) 760 return ret; 761 attrcount++; 762 } 763 764 return attrcount; 765 } 766 767 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev, 768 struct iio_chan_spec const *chan) 769 { 770 int ret, attrcount = 0; 771 const struct iio_chan_spec_ext_info *ext_info; 772 773 if (chan->channel < 0) 774 return 0; 775 ret = iio_device_add_info_mask_type(indio_dev, chan, 776 IIO_SEPARATE, 777 &chan->info_mask_separate); 778 if (ret < 0) 779 return ret; 780 attrcount += ret; 781 782 ret = iio_device_add_info_mask_type(indio_dev, chan, 783 IIO_SHARED_BY_TYPE, 784 &chan->info_mask_shared_by_type); 785 if (ret < 0) 786 return ret; 787 attrcount += ret; 788 789 ret = iio_device_add_info_mask_type(indio_dev, chan, 790 IIO_SHARED_BY_DIR, 791 &chan->info_mask_shared_by_dir); 792 if (ret < 0) 793 return ret; 794 attrcount += ret; 795 796 ret = iio_device_add_info_mask_type(indio_dev, chan, 797 IIO_SHARED_BY_ALL, 798 &chan->info_mask_shared_by_all); 799 if (ret < 0) 800 return ret; 801 attrcount += ret; 802 803 if (chan->ext_info) { 804 unsigned int i = 0; 805 for (ext_info = chan->ext_info; ext_info->name; ext_info++) { 806 ret = __iio_add_chan_devattr(ext_info->name, 807 chan, 808 ext_info->read ? 809 &iio_read_channel_ext_info : NULL, 810 ext_info->write ? 811 &iio_write_channel_ext_info : NULL, 812 i, 813 ext_info->shared, 814 &indio_dev->dev, 815 &indio_dev->channel_attr_list); 816 i++; 817 if (ret == -EBUSY && ext_info->shared) 818 continue; 819 820 if (ret) 821 return ret; 822 823 attrcount++; 824 } 825 } 826 827 return attrcount; 828 } 829 830 /** 831 * iio_free_chan_devattr_list() - Free a list of IIO device attributes 832 * @attr_list: List of IIO device attributes 833 * 834 * This function frees the memory allocated for each of the IIO device 835 * attributes in the list. Note: if you want to reuse the list after calling 836 * this function you have to reinitialize it using INIT_LIST_HEAD(). 837 */ 838 void iio_free_chan_devattr_list(struct list_head *attr_list) 839 { 840 struct iio_dev_attr *p, *n; 841 842 list_for_each_entry_safe(p, n, attr_list, l) { 843 kfree(p->dev_attr.attr.name); 844 kfree(p); 845 } 846 } 847 848 static ssize_t iio_show_dev_name(struct device *dev, 849 struct device_attribute *attr, 850 char *buf) 851 { 852 struct iio_dev *indio_dev = dev_to_iio_dev(dev); 853 return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name); 854 } 855 856 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL); 857 858 static int iio_device_register_sysfs(struct iio_dev *indio_dev) 859 { 860 int i, ret = 0, attrcount, attrn, attrcount_orig = 0; 861 struct iio_dev_attr *p; 862 struct attribute **attr; 863 864 /* First count elements in any existing group */ 865 if (indio_dev->info->attrs) { 866 attr = indio_dev->info->attrs->attrs; 867 while (*attr++ != NULL) 868 attrcount_orig++; 869 } 870 attrcount = attrcount_orig; 871 /* 872 * New channel registration method - relies on the fact a group does 873 * not need to be initialized if its name is NULL. 874 */ 875 if (indio_dev->channels) 876 for (i = 0; i < indio_dev->num_channels; i++) { 877 ret = iio_device_add_channel_sysfs(indio_dev, 878 &indio_dev 879 ->channels[i]); 880 if (ret < 0) 881 goto error_clear_attrs; 882 attrcount += ret; 883 } 884 885 if (indio_dev->name) 886 attrcount++; 887 888 indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1, 889 sizeof(indio_dev->chan_attr_group.attrs[0]), 890 GFP_KERNEL); 891 if (indio_dev->chan_attr_group.attrs == NULL) { 892 ret = -ENOMEM; 893 goto error_clear_attrs; 894 } 895 /* Copy across original attributes */ 896 if (indio_dev->info->attrs) 897 memcpy(indio_dev->chan_attr_group.attrs, 898 indio_dev->info->attrs->attrs, 899 sizeof(indio_dev->chan_attr_group.attrs[0]) 900 *attrcount_orig); 901 attrn = attrcount_orig; 902 /* Add all elements from the list. */ 903 list_for_each_entry(p, &indio_dev->channel_attr_list, l) 904 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr; 905 if (indio_dev->name) 906 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr; 907 908 indio_dev->groups[indio_dev->groupcounter++] = 909 &indio_dev->chan_attr_group; 910 911 return 0; 912 913 error_clear_attrs: 914 iio_free_chan_devattr_list(&indio_dev->channel_attr_list); 915 916 return ret; 917 } 918 919 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev) 920 { 921 922 iio_free_chan_devattr_list(&indio_dev->channel_attr_list); 923 kfree(indio_dev->chan_attr_group.attrs); 924 } 925 926 static void iio_dev_release(struct device *device) 927 { 928 struct iio_dev *indio_dev = dev_to_iio_dev(device); 929 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED) 930 iio_device_unregister_trigger_consumer(indio_dev); 931 iio_device_unregister_eventset(indio_dev); 932 iio_device_unregister_sysfs(indio_dev); 933 934 iio_buffer_put(indio_dev->buffer); 935 936 ida_simple_remove(&iio_ida, indio_dev->id); 937 kfree(indio_dev); 938 } 939 940 struct device_type iio_device_type = { 941 .name = "iio_device", 942 .release = iio_dev_release, 943 }; 944 945 /** 946 * iio_device_alloc() - allocate an iio_dev from a driver 947 * @sizeof_priv: Space to allocate for private structure. 948 **/ 949 struct iio_dev *iio_device_alloc(int sizeof_priv) 950 { 951 struct iio_dev *dev; 952 size_t alloc_size; 953 954 alloc_size = sizeof(struct iio_dev); 955 if (sizeof_priv) { 956 alloc_size = ALIGN(alloc_size, IIO_ALIGN); 957 alloc_size += sizeof_priv; 958 } 959 /* ensure 32-byte alignment of whole construct ? */ 960 alloc_size += IIO_ALIGN - 1; 961 962 dev = kzalloc(alloc_size, GFP_KERNEL); 963 964 if (dev) { 965 dev->dev.groups = dev->groups; 966 dev->dev.type = &iio_device_type; 967 dev->dev.bus = &iio_bus_type; 968 device_initialize(&dev->dev); 969 dev_set_drvdata(&dev->dev, (void *)dev); 970 mutex_init(&dev->mlock); 971 mutex_init(&dev->info_exist_lock); 972 INIT_LIST_HEAD(&dev->channel_attr_list); 973 974 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL); 975 if (dev->id < 0) { 976 /* cannot use a dev_err as the name isn't available */ 977 pr_err("failed to get device id\n"); 978 kfree(dev); 979 return NULL; 980 } 981 dev_set_name(&dev->dev, "iio:device%d", dev->id); 982 INIT_LIST_HEAD(&dev->buffer_list); 983 } 984 985 return dev; 986 } 987 EXPORT_SYMBOL(iio_device_alloc); 988 989 /** 990 * iio_device_free() - free an iio_dev from a driver 991 * @dev: the iio_dev associated with the device 992 **/ 993 void iio_device_free(struct iio_dev *dev) 994 { 995 if (dev) 996 put_device(&dev->dev); 997 } 998 EXPORT_SYMBOL(iio_device_free); 999 1000 static void devm_iio_device_release(struct device *dev, void *res) 1001 { 1002 iio_device_free(*(struct iio_dev **)res); 1003 } 1004 1005 static int devm_iio_device_match(struct device *dev, void *res, void *data) 1006 { 1007 struct iio_dev **r = res; 1008 if (!r || !*r) { 1009 WARN_ON(!r || !*r); 1010 return 0; 1011 } 1012 return *r == data; 1013 } 1014 1015 /** 1016 * devm_iio_device_alloc - Resource-managed iio_device_alloc() 1017 * @dev: Device to allocate iio_dev for 1018 * @sizeof_priv: Space to allocate for private structure. 1019 * 1020 * Managed iio_device_alloc. iio_dev allocated with this function is 1021 * automatically freed on driver detach. 1022 * 1023 * If an iio_dev allocated with this function needs to be freed separately, 1024 * devm_iio_device_free() must be used. 1025 * 1026 * RETURNS: 1027 * Pointer to allocated iio_dev on success, NULL on failure. 1028 */ 1029 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv) 1030 { 1031 struct iio_dev **ptr, *iio_dev; 1032 1033 ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr), 1034 GFP_KERNEL); 1035 if (!ptr) 1036 return NULL; 1037 1038 /* use raw alloc_dr for kmalloc caller tracing */ 1039 iio_dev = iio_device_alloc(sizeof_priv); 1040 if (iio_dev) { 1041 *ptr = iio_dev; 1042 devres_add(dev, ptr); 1043 } else { 1044 devres_free(ptr); 1045 } 1046 1047 return iio_dev; 1048 } 1049 EXPORT_SYMBOL_GPL(devm_iio_device_alloc); 1050 1051 /** 1052 * devm_iio_device_free - Resource-managed iio_device_free() 1053 * @dev: Device this iio_dev belongs to 1054 * @iio_dev: the iio_dev associated with the device 1055 * 1056 * Free iio_dev allocated with devm_iio_device_alloc(). 1057 */ 1058 void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev) 1059 { 1060 int rc; 1061 1062 rc = devres_release(dev, devm_iio_device_release, 1063 devm_iio_device_match, iio_dev); 1064 WARN_ON(rc); 1065 } 1066 EXPORT_SYMBOL_GPL(devm_iio_device_free); 1067 1068 /** 1069 * iio_chrdev_open() - chrdev file open for buffer access and ioctls 1070 **/ 1071 static int iio_chrdev_open(struct inode *inode, struct file *filp) 1072 { 1073 struct iio_dev *indio_dev = container_of(inode->i_cdev, 1074 struct iio_dev, chrdev); 1075 1076 if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags)) 1077 return -EBUSY; 1078 1079 iio_device_get(indio_dev); 1080 1081 filp->private_data = indio_dev; 1082 1083 return 0; 1084 } 1085 1086 /** 1087 * iio_chrdev_release() - chrdev file close buffer access and ioctls 1088 **/ 1089 static int iio_chrdev_release(struct inode *inode, struct file *filp) 1090 { 1091 struct iio_dev *indio_dev = container_of(inode->i_cdev, 1092 struct iio_dev, chrdev); 1093 clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags); 1094 iio_device_put(indio_dev); 1095 1096 return 0; 1097 } 1098 1099 /* Somewhat of a cross file organization violation - ioctls here are actually 1100 * event related */ 1101 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 1102 { 1103 struct iio_dev *indio_dev = filp->private_data; 1104 int __user *ip = (int __user *)arg; 1105 int fd; 1106 1107 if (!indio_dev->info) 1108 return -ENODEV; 1109 1110 if (cmd == IIO_GET_EVENT_FD_IOCTL) { 1111 fd = iio_event_getfd(indio_dev); 1112 if (copy_to_user(ip, &fd, sizeof(fd))) 1113 return -EFAULT; 1114 return 0; 1115 } 1116 return -EINVAL; 1117 } 1118 1119 static const struct file_operations iio_buffer_fileops = { 1120 .read = iio_buffer_read_first_n_outer_addr, 1121 .release = iio_chrdev_release, 1122 .open = iio_chrdev_open, 1123 .poll = iio_buffer_poll_addr, 1124 .owner = THIS_MODULE, 1125 .llseek = noop_llseek, 1126 .unlocked_ioctl = iio_ioctl, 1127 .compat_ioctl = iio_ioctl, 1128 }; 1129 1130 static const struct iio_buffer_setup_ops noop_ring_setup_ops; 1131 1132 /** 1133 * iio_device_register() - register a device with the IIO subsystem 1134 * @indio_dev: Device structure filled by the device driver 1135 **/ 1136 int iio_device_register(struct iio_dev *indio_dev) 1137 { 1138 int ret; 1139 1140 /* If the calling driver did not initialize of_node, do it here */ 1141 if (!indio_dev->dev.of_node && indio_dev->dev.parent) 1142 indio_dev->dev.of_node = indio_dev->dev.parent->of_node; 1143 1144 /* configure elements for the chrdev */ 1145 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id); 1146 1147 ret = iio_device_register_debugfs(indio_dev); 1148 if (ret) { 1149 dev_err(indio_dev->dev.parent, 1150 "Failed to register debugfs interfaces\n"); 1151 return ret; 1152 } 1153 ret = iio_device_register_sysfs(indio_dev); 1154 if (ret) { 1155 dev_err(indio_dev->dev.parent, 1156 "Failed to register sysfs interfaces\n"); 1157 goto error_unreg_debugfs; 1158 } 1159 ret = iio_device_register_eventset(indio_dev); 1160 if (ret) { 1161 dev_err(indio_dev->dev.parent, 1162 "Failed to register event set\n"); 1163 goto error_free_sysfs; 1164 } 1165 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED) 1166 iio_device_register_trigger_consumer(indio_dev); 1167 1168 if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) && 1169 indio_dev->setup_ops == NULL) 1170 indio_dev->setup_ops = &noop_ring_setup_ops; 1171 1172 cdev_init(&indio_dev->chrdev, &iio_buffer_fileops); 1173 indio_dev->chrdev.owner = indio_dev->info->driver_module; 1174 indio_dev->chrdev.kobj.parent = &indio_dev->dev.kobj; 1175 ret = cdev_add(&indio_dev->chrdev, indio_dev->dev.devt, 1); 1176 if (ret < 0) 1177 goto error_unreg_eventset; 1178 1179 ret = device_add(&indio_dev->dev); 1180 if (ret < 0) 1181 goto error_cdev_del; 1182 1183 return 0; 1184 error_cdev_del: 1185 cdev_del(&indio_dev->chrdev); 1186 error_unreg_eventset: 1187 iio_device_unregister_eventset(indio_dev); 1188 error_free_sysfs: 1189 iio_device_unregister_sysfs(indio_dev); 1190 error_unreg_debugfs: 1191 iio_device_unregister_debugfs(indio_dev); 1192 return ret; 1193 } 1194 EXPORT_SYMBOL(iio_device_register); 1195 1196 /** 1197 * iio_device_unregister() - unregister a device from the IIO subsystem 1198 * @indio_dev: Device structure representing the device. 1199 **/ 1200 void iio_device_unregister(struct iio_dev *indio_dev) 1201 { 1202 mutex_lock(&indio_dev->info_exist_lock); 1203 1204 device_del(&indio_dev->dev); 1205 1206 if (indio_dev->chrdev.dev) 1207 cdev_del(&indio_dev->chrdev); 1208 iio_device_unregister_debugfs(indio_dev); 1209 1210 iio_disable_all_buffers(indio_dev); 1211 1212 indio_dev->info = NULL; 1213 1214 iio_device_wakeup_eventset(indio_dev); 1215 iio_buffer_wakeup_poll(indio_dev); 1216 1217 mutex_unlock(&indio_dev->info_exist_lock); 1218 } 1219 EXPORT_SYMBOL(iio_device_unregister); 1220 1221 static void devm_iio_device_unreg(struct device *dev, void *res) 1222 { 1223 iio_device_unregister(*(struct iio_dev **)res); 1224 } 1225 1226 /** 1227 * devm_iio_device_register - Resource-managed iio_device_register() 1228 * @dev: Device to allocate iio_dev for 1229 * @indio_dev: Device structure filled by the device driver 1230 * 1231 * Managed iio_device_register. The IIO device registered with this 1232 * function is automatically unregistered on driver detach. This function 1233 * calls iio_device_register() internally. Refer to that function for more 1234 * information. 1235 * 1236 * If an iio_dev registered with this function needs to be unregistered 1237 * separately, devm_iio_device_unregister() must be used. 1238 * 1239 * RETURNS: 1240 * 0 on success, negative error number on failure. 1241 */ 1242 int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev) 1243 { 1244 struct iio_dev **ptr; 1245 int ret; 1246 1247 ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL); 1248 if (!ptr) 1249 return -ENOMEM; 1250 1251 *ptr = indio_dev; 1252 ret = iio_device_register(indio_dev); 1253 if (!ret) 1254 devres_add(dev, ptr); 1255 else 1256 devres_free(ptr); 1257 1258 return ret; 1259 } 1260 EXPORT_SYMBOL_GPL(devm_iio_device_register); 1261 1262 /** 1263 * devm_iio_device_unregister - Resource-managed iio_device_unregister() 1264 * @dev: Device this iio_dev belongs to 1265 * @indio_dev: the iio_dev associated with the device 1266 * 1267 * Unregister iio_dev registered with devm_iio_device_register(). 1268 */ 1269 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev) 1270 { 1271 int rc; 1272 1273 rc = devres_release(dev, devm_iio_device_unreg, 1274 devm_iio_device_match, indio_dev); 1275 WARN_ON(rc); 1276 } 1277 EXPORT_SYMBOL_GPL(devm_iio_device_unregister); 1278 1279 subsys_initcall(iio_init); 1280 module_exit(iio_exit); 1281 1282 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>"); 1283 MODULE_DESCRIPTION("Industrial I/O core"); 1284 MODULE_LICENSE("GPL"); 1285