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