linux/drivers/base/property.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * property.c - Unified device property interface.
   4 *
   5 * Copyright (C) 2014, Intel Corporation
   6 * Authors: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
   7 *          Mika Westerberg <mika.westerberg@linux.intel.com>
   8 */
   9
  10#include <linux/acpi.h>
  11#include <linux/export.h>
  12#include <linux/kernel.h>
  13#include <linux/of.h>
  14#include <linux/of_address.h>
  15#include <linux/of_graph.h>
  16#include <linux/of_irq.h>
  17#include <linux/property.h>
  18#include <linux/phy.h>
  19
  20struct fwnode_handle *dev_fwnode(struct device *dev)
  21{
  22        return IS_ENABLED(CONFIG_OF) && dev->of_node ?
  23                of_fwnode_handle(dev->of_node) : dev->fwnode;
  24}
  25EXPORT_SYMBOL_GPL(dev_fwnode);
  26
  27/**
  28 * device_property_present - check if a property of a device is present
  29 * @dev: Device whose property is being checked
  30 * @propname: Name of the property
  31 *
  32 * Check if property @propname is present in the device firmware description.
  33 */
  34bool device_property_present(struct device *dev, const char *propname)
  35{
  36        return fwnode_property_present(dev_fwnode(dev), propname);
  37}
  38EXPORT_SYMBOL_GPL(device_property_present);
  39
  40/**
  41 * fwnode_property_present - check if a property of a firmware node is present
  42 * @fwnode: Firmware node whose property to check
  43 * @propname: Name of the property
  44 */
  45bool fwnode_property_present(const struct fwnode_handle *fwnode,
  46                             const char *propname)
  47{
  48        bool ret;
  49
  50        ret = fwnode_call_bool_op(fwnode, property_present, propname);
  51        if (ret == false && !IS_ERR_OR_NULL(fwnode) &&
  52            !IS_ERR_OR_NULL(fwnode->secondary))
  53                ret = fwnode_call_bool_op(fwnode->secondary, property_present,
  54                                         propname);
  55        return ret;
  56}
  57EXPORT_SYMBOL_GPL(fwnode_property_present);
  58
  59/**
  60 * device_property_read_u8_array - return a u8 array property of a device
  61 * @dev: Device to get the property of
  62 * @propname: Name of the property
  63 * @val: The values are stored here or %NULL to return the number of values
  64 * @nval: Size of the @val array
  65 *
  66 * Function reads an array of u8 properties with @propname from the device
  67 * firmware description and stores them to @val if found.
  68 *
  69 * Return: number of values if @val was %NULL,
  70 *         %0 if the property was found (success),
  71 *         %-EINVAL if given arguments are not valid,
  72 *         %-ENODATA if the property does not have a value,
  73 *         %-EPROTO if the property is not an array of numbers,
  74 *         %-EOVERFLOW if the size of the property is not as expected.
  75 *         %-ENXIO if no suitable firmware interface is present.
  76 */
  77int device_property_read_u8_array(struct device *dev, const char *propname,
  78                                  u8 *val, size_t nval)
  79{
  80        return fwnode_property_read_u8_array(dev_fwnode(dev), propname, val, nval);
  81}
  82EXPORT_SYMBOL_GPL(device_property_read_u8_array);
  83
  84/**
  85 * device_property_read_u16_array - return a u16 array property of a device
  86 * @dev: Device to get the property of
  87 * @propname: Name of the property
  88 * @val: The values are stored here or %NULL to return the number of values
  89 * @nval: Size of the @val array
  90 *
  91 * Function reads an array of u16 properties with @propname from the device
  92 * firmware description and stores them to @val if found.
  93 *
  94 * Return: number of values if @val was %NULL,
  95 *         %0 if the property was found (success),
  96 *         %-EINVAL if given arguments are not valid,
  97 *         %-ENODATA if the property does not have a value,
  98 *         %-EPROTO if the property is not an array of numbers,
  99 *         %-EOVERFLOW if the size of the property is not as expected.
 100 *         %-ENXIO if no suitable firmware interface is present.
 101 */
 102int device_property_read_u16_array(struct device *dev, const char *propname,
 103                                   u16 *val, size_t nval)
 104{
 105        return fwnode_property_read_u16_array(dev_fwnode(dev), propname, val, nval);
 106}
 107EXPORT_SYMBOL_GPL(device_property_read_u16_array);
 108
 109/**
 110 * device_property_read_u32_array - return a u32 array property of a device
 111 * @dev: Device to get the property of
 112 * @propname: Name of the property
 113 * @val: The values are stored here or %NULL to return the number of values
 114 * @nval: Size of the @val array
 115 *
 116 * Function reads an array of u32 properties with @propname from the device
 117 * firmware description and stores them to @val if found.
 118 *
 119 * Return: number of values if @val was %NULL,
 120 *         %0 if the property was found (success),
 121 *         %-EINVAL if given arguments are not valid,
 122 *         %-ENODATA if the property does not have a value,
 123 *         %-EPROTO if the property is not an array of numbers,
 124 *         %-EOVERFLOW if the size of the property is not as expected.
 125 *         %-ENXIO if no suitable firmware interface is present.
 126 */
 127int device_property_read_u32_array(struct device *dev, const char *propname,
 128                                   u32 *val, size_t nval)
 129{
 130        return fwnode_property_read_u32_array(dev_fwnode(dev), propname, val, nval);
 131}
 132EXPORT_SYMBOL_GPL(device_property_read_u32_array);
 133
 134/**
 135 * device_property_read_u64_array - return a u64 array property of a device
 136 * @dev: Device to get the property of
 137 * @propname: Name of the property
 138 * @val: The values are stored here or %NULL to return the number of values
 139 * @nval: Size of the @val array
 140 *
 141 * Function reads an array of u64 properties with @propname from the device
 142 * firmware description and stores them to @val if found.
 143 *
 144 * Return: number of values if @val was %NULL,
 145 *         %0 if the property was found (success),
 146 *         %-EINVAL if given arguments are not valid,
 147 *         %-ENODATA if the property does not have a value,
 148 *         %-EPROTO if the property is not an array of numbers,
 149 *         %-EOVERFLOW if the size of the property is not as expected.
 150 *         %-ENXIO if no suitable firmware interface is present.
 151 */
 152int device_property_read_u64_array(struct device *dev, const char *propname,
 153                                   u64 *val, size_t nval)
 154{
 155        return fwnode_property_read_u64_array(dev_fwnode(dev), propname, val, nval);
 156}
 157EXPORT_SYMBOL_GPL(device_property_read_u64_array);
 158
 159/**
 160 * device_property_read_string_array - return a string array property of device
 161 * @dev: Device to get the property of
 162 * @propname: Name of the property
 163 * @val: The values are stored here or %NULL to return the number of values
 164 * @nval: Size of the @val array
 165 *
 166 * Function reads an array of string properties with @propname from the device
 167 * firmware description and stores them to @val if found.
 168 *
 169 * Return: number of values read on success if @val is non-NULL,
 170 *         number of values available on success if @val is NULL,
 171 *         %-EINVAL if given arguments are not valid,
 172 *         %-ENODATA if the property does not have a value,
 173 *         %-EPROTO or %-EILSEQ if the property is not an array of strings,
 174 *         %-EOVERFLOW if the size of the property is not as expected.
 175 *         %-ENXIO if no suitable firmware interface is present.
 176 */
 177int device_property_read_string_array(struct device *dev, const char *propname,
 178                                      const char **val, size_t nval)
 179{
 180        return fwnode_property_read_string_array(dev_fwnode(dev), propname, val, nval);
 181}
 182EXPORT_SYMBOL_GPL(device_property_read_string_array);
 183
 184/**
 185 * device_property_read_string - return a string property of a device
 186 * @dev: Device to get the property of
 187 * @propname: Name of the property
 188 * @val: The value is stored here
 189 *
 190 * Function reads property @propname from the device firmware description and
 191 * stores the value into @val if found. The value is checked to be a string.
 192 *
 193 * Return: %0 if the property was found (success),
 194 *         %-EINVAL if given arguments are not valid,
 195 *         %-ENODATA if the property does not have a value,
 196 *         %-EPROTO or %-EILSEQ if the property type is not a string.
 197 *         %-ENXIO if no suitable firmware interface is present.
 198 */
 199int device_property_read_string(struct device *dev, const char *propname,
 200                                const char **val)
 201{
 202        return fwnode_property_read_string(dev_fwnode(dev), propname, val);
 203}
 204EXPORT_SYMBOL_GPL(device_property_read_string);
 205
 206/**
 207 * device_property_match_string - find a string in an array and return index
 208 * @dev: Device to get the property of
 209 * @propname: Name of the property holding the array
 210 * @string: String to look for
 211 *
 212 * Find a given string in a string array and if it is found return the
 213 * index back.
 214 *
 215 * Return: %0 if the property was found (success),
 216 *         %-EINVAL if given arguments are not valid,
 217 *         %-ENODATA if the property does not have a value,
 218 *         %-EPROTO if the property is not an array of strings,
 219 *         %-ENXIO if no suitable firmware interface is present.
 220 */
 221int device_property_match_string(struct device *dev, const char *propname,
 222                                 const char *string)
 223{
 224        return fwnode_property_match_string(dev_fwnode(dev), propname, string);
 225}
 226EXPORT_SYMBOL_GPL(device_property_match_string);
 227
 228static int fwnode_property_read_int_array(const struct fwnode_handle *fwnode,
 229                                          const char *propname,
 230                                          unsigned int elem_size, void *val,
 231                                          size_t nval)
 232{
 233        int ret;
 234
 235        ret = fwnode_call_int_op(fwnode, property_read_int_array, propname,
 236                                 elem_size, val, nval);
 237        if (ret == -EINVAL && !IS_ERR_OR_NULL(fwnode) &&
 238            !IS_ERR_OR_NULL(fwnode->secondary))
 239                ret = fwnode_call_int_op(
 240                        fwnode->secondary, property_read_int_array, propname,
 241                        elem_size, val, nval);
 242
 243        return ret;
 244}
 245
 246/**
 247 * fwnode_property_read_u8_array - return a u8 array property of firmware node
 248 * @fwnode: Firmware node to get the property of
 249 * @propname: Name of the property
 250 * @val: The values are stored here or %NULL to return the number of values
 251 * @nval: Size of the @val array
 252 *
 253 * Read an array of u8 properties with @propname from @fwnode and stores them to
 254 * @val if found.
 255 *
 256 * Return: number of values if @val was %NULL,
 257 *         %0 if the property was found (success),
 258 *         %-EINVAL if given arguments are not valid,
 259 *         %-ENODATA if the property does not have a value,
 260 *         %-EPROTO if the property is not an array of numbers,
 261 *         %-EOVERFLOW if the size of the property is not as expected,
 262 *         %-ENXIO if no suitable firmware interface is present.
 263 */
 264int fwnode_property_read_u8_array(const struct fwnode_handle *fwnode,
 265                                  const char *propname, u8 *val, size_t nval)
 266{
 267        return fwnode_property_read_int_array(fwnode, propname, sizeof(u8),
 268                                              val, nval);
 269}
 270EXPORT_SYMBOL_GPL(fwnode_property_read_u8_array);
 271
 272/**
 273 * fwnode_property_read_u16_array - return a u16 array property of firmware node
 274 * @fwnode: Firmware node to get the property of
 275 * @propname: Name of the property
 276 * @val: The values are stored here or %NULL to return the number of values
 277 * @nval: Size of the @val array
 278 *
 279 * Read an array of u16 properties with @propname from @fwnode and store them to
 280 * @val if found.
 281 *
 282 * Return: number of values if @val was %NULL,
 283 *         %0 if the property was found (success),
 284 *         %-EINVAL if given arguments are not valid,
 285 *         %-ENODATA if the property does not have a value,
 286 *         %-EPROTO if the property is not an array of numbers,
 287 *         %-EOVERFLOW if the size of the property is not as expected,
 288 *         %-ENXIO if no suitable firmware interface is present.
 289 */
 290int fwnode_property_read_u16_array(const struct fwnode_handle *fwnode,
 291                                   const char *propname, u16 *val, size_t nval)
 292{
 293        return fwnode_property_read_int_array(fwnode, propname, sizeof(u16),
 294                                              val, nval);
 295}
 296EXPORT_SYMBOL_GPL(fwnode_property_read_u16_array);
 297
 298/**
 299 * fwnode_property_read_u32_array - return a u32 array property of firmware node
 300 * @fwnode: Firmware node to get the property of
 301 * @propname: Name of the property
 302 * @val: The values are stored here or %NULL to return the number of values
 303 * @nval: Size of the @val array
 304 *
 305 * Read an array of u32 properties with @propname from @fwnode store them to
 306 * @val if found.
 307 *
 308 * Return: number of values if @val was %NULL,
 309 *         %0 if the property was found (success),
 310 *         %-EINVAL if given arguments are not valid,
 311 *         %-ENODATA if the property does not have a value,
 312 *         %-EPROTO if the property is not an array of numbers,
 313 *         %-EOVERFLOW if the size of the property is not as expected,
 314 *         %-ENXIO if no suitable firmware interface is present.
 315 */
 316int fwnode_property_read_u32_array(const struct fwnode_handle *fwnode,
 317                                   const char *propname, u32 *val, size_t nval)
 318{
 319        return fwnode_property_read_int_array(fwnode, propname, sizeof(u32),
 320                                              val, nval);
 321}
 322EXPORT_SYMBOL_GPL(fwnode_property_read_u32_array);
 323
 324/**
 325 * fwnode_property_read_u64_array - return a u64 array property firmware node
 326 * @fwnode: Firmware node to get the property of
 327 * @propname: Name of the property
 328 * @val: The values are stored here or %NULL to return the number of values
 329 * @nval: Size of the @val array
 330 *
 331 * Read an array of u64 properties with @propname from @fwnode and store them to
 332 * @val if found.
 333 *
 334 * Return: number of values if @val was %NULL,
 335 *         %0 if the property was found (success),
 336 *         %-EINVAL if given arguments are not valid,
 337 *         %-ENODATA if the property does not have a value,
 338 *         %-EPROTO if the property is not an array of numbers,
 339 *         %-EOVERFLOW if the size of the property is not as expected,
 340 *         %-ENXIO if no suitable firmware interface is present.
 341 */
 342int fwnode_property_read_u64_array(const struct fwnode_handle *fwnode,
 343                                   const char *propname, u64 *val, size_t nval)
 344{
 345        return fwnode_property_read_int_array(fwnode, propname, sizeof(u64),
 346                                              val, nval);
 347}
 348EXPORT_SYMBOL_GPL(fwnode_property_read_u64_array);
 349
 350/**
 351 * fwnode_property_read_string_array - return string array property of a node
 352 * @fwnode: Firmware node to get the property of
 353 * @propname: Name of the property
 354 * @val: The values are stored here or %NULL to return the number of values
 355 * @nval: Size of the @val array
 356 *
 357 * Read an string list property @propname from the given firmware node and store
 358 * them to @val if found.
 359 *
 360 * Return: number of values read on success if @val is non-NULL,
 361 *         number of values available on success if @val is NULL,
 362 *         %-EINVAL if given arguments are not valid,
 363 *         %-ENODATA if the property does not have a value,
 364 *         %-EPROTO or %-EILSEQ if the property is not an array of strings,
 365 *         %-EOVERFLOW if the size of the property is not as expected,
 366 *         %-ENXIO if no suitable firmware interface is present.
 367 */
 368int fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
 369                                      const char *propname, const char **val,
 370                                      size_t nval)
 371{
 372        int ret;
 373
 374        ret = fwnode_call_int_op(fwnode, property_read_string_array, propname,
 375                                 val, nval);
 376        if (ret == -EINVAL && !IS_ERR_OR_NULL(fwnode) &&
 377            !IS_ERR_OR_NULL(fwnode->secondary))
 378                ret = fwnode_call_int_op(fwnode->secondary,
 379                                         property_read_string_array, propname,
 380                                         val, nval);
 381        return ret;
 382}
 383EXPORT_SYMBOL_GPL(fwnode_property_read_string_array);
 384
 385/**
 386 * fwnode_property_read_string - return a string property of a firmware node
 387 * @fwnode: Firmware node to get the property of
 388 * @propname: Name of the property
 389 * @val: The value is stored here
 390 *
 391 * Read property @propname from the given firmware node and store the value into
 392 * @val if found.  The value is checked to be a string.
 393 *
 394 * Return: %0 if the property was found (success),
 395 *         %-EINVAL if given arguments are not valid,
 396 *         %-ENODATA if the property does not have a value,
 397 *         %-EPROTO or %-EILSEQ if the property is not a string,
 398 *         %-ENXIO if no suitable firmware interface is present.
 399 */
 400int fwnode_property_read_string(const struct fwnode_handle *fwnode,
 401                                const char *propname, const char **val)
 402{
 403        int ret = fwnode_property_read_string_array(fwnode, propname, val, 1);
 404
 405        return ret < 0 ? ret : 0;
 406}
 407EXPORT_SYMBOL_GPL(fwnode_property_read_string);
 408
 409/**
 410 * fwnode_property_match_string - find a string in an array and return index
 411 * @fwnode: Firmware node to get the property of
 412 * @propname: Name of the property holding the array
 413 * @string: String to look for
 414 *
 415 * Find a given string in a string array and if it is found return the
 416 * index back.
 417 *
 418 * Return: %0 if the property was found (success),
 419 *         %-EINVAL if given arguments are not valid,
 420 *         %-ENODATA if the property does not have a value,
 421 *         %-EPROTO if the property is not an array of strings,
 422 *         %-ENXIO if no suitable firmware interface is present.
 423 */
 424int fwnode_property_match_string(const struct fwnode_handle *fwnode,
 425        const char *propname, const char *string)
 426{
 427        const char **values;
 428        int nval, ret;
 429
 430        nval = fwnode_property_read_string_array(fwnode, propname, NULL, 0);
 431        if (nval < 0)
 432                return nval;
 433
 434        if (nval == 0)
 435                return -ENODATA;
 436
 437        values = kcalloc(nval, sizeof(*values), GFP_KERNEL);
 438        if (!values)
 439                return -ENOMEM;
 440
 441        ret = fwnode_property_read_string_array(fwnode, propname, values, nval);
 442        if (ret < 0)
 443                goto out;
 444
 445        ret = match_string(values, nval, string);
 446        if (ret < 0)
 447                ret = -ENODATA;
 448out:
 449        kfree(values);
 450        return ret;
 451}
 452EXPORT_SYMBOL_GPL(fwnode_property_match_string);
 453
 454/**
 455 * fwnode_property_get_reference_args() - Find a reference with arguments
 456 * @fwnode:     Firmware node where to look for the reference
 457 * @prop:       The name of the property
 458 * @nargs_prop: The name of the property telling the number of
 459 *              arguments in the referred node. NULL if @nargs is known,
 460 *              otherwise @nargs is ignored. Only relevant on OF.
 461 * @nargs:      Number of arguments. Ignored if @nargs_prop is non-NULL.
 462 * @index:      Index of the reference, from zero onwards.
 463 * @args:       Result structure with reference and integer arguments.
 464 *
 465 * Obtain a reference based on a named property in an fwnode, with
 466 * integer arguments.
 467 *
 468 * Caller is responsible to call fwnode_handle_put() on the returned
 469 * args->fwnode pointer.
 470 *
 471 * Returns: %0 on success
 472 *          %-ENOENT when the index is out of bounds, the index has an empty
 473 *                   reference or the property was not found
 474 *          %-EINVAL on parse error
 475 */
 476int fwnode_property_get_reference_args(const struct fwnode_handle *fwnode,
 477                                       const char *prop, const char *nargs_prop,
 478                                       unsigned int nargs, unsigned int index,
 479                                       struct fwnode_reference_args *args)
 480{
 481        int ret;
 482
 483        ret = fwnode_call_int_op(fwnode, get_reference_args, prop, nargs_prop,
 484                                 nargs, index, args);
 485
 486        if (ret < 0 && !IS_ERR_OR_NULL(fwnode) &&
 487            !IS_ERR_OR_NULL(fwnode->secondary))
 488                ret = fwnode_call_int_op(fwnode->secondary, get_reference_args,
 489                                         prop, nargs_prop, nargs, index, args);
 490
 491        return ret;
 492}
 493EXPORT_SYMBOL_GPL(fwnode_property_get_reference_args);
 494
 495/**
 496 * fwnode_find_reference - Find named reference to a fwnode_handle
 497 * @fwnode: Firmware node where to look for the reference
 498 * @name: The name of the reference
 499 * @index: Index of the reference
 500 *
 501 * @index can be used when the named reference holds a table of references.
 502 *
 503 * Returns pointer to the reference fwnode, or ERR_PTR. Caller is responsible to
 504 * call fwnode_handle_put() on the returned fwnode pointer.
 505 */
 506struct fwnode_handle *fwnode_find_reference(const struct fwnode_handle *fwnode,
 507                                            const char *name,
 508                                            unsigned int index)
 509{
 510        struct fwnode_reference_args args;
 511        int ret;
 512
 513        ret = fwnode_property_get_reference_args(fwnode, name, NULL, 0, index,
 514                                                 &args);
 515        return ret ? ERR_PTR(ret) : args.fwnode;
 516}
 517EXPORT_SYMBOL_GPL(fwnode_find_reference);
 518
 519/**
 520 * fwnode_get_name - Return the name of a node
 521 * @fwnode: The firmware node
 522 *
 523 * Returns a pointer to the node name.
 524 */
 525const char *fwnode_get_name(const struct fwnode_handle *fwnode)
 526{
 527        return fwnode_call_ptr_op(fwnode, get_name);
 528}
 529EXPORT_SYMBOL_GPL(fwnode_get_name);
 530
 531/**
 532 * fwnode_get_name_prefix - Return the prefix of node for printing purposes
 533 * @fwnode: The firmware node
 534 *
 535 * Returns the prefix of a node, intended to be printed right before the node.
 536 * The prefix works also as a separator between the nodes.
 537 */
 538const char *fwnode_get_name_prefix(const struct fwnode_handle *fwnode)
 539{
 540        return fwnode_call_ptr_op(fwnode, get_name_prefix);
 541}
 542
 543/**
 544 * fwnode_get_parent - Return parent firwmare node
 545 * @fwnode: Firmware whose parent is retrieved
 546 *
 547 * Return parent firmware node of the given node if possible or %NULL if no
 548 * parent was available.
 549 */
 550struct fwnode_handle *fwnode_get_parent(const struct fwnode_handle *fwnode)
 551{
 552        return fwnode_call_ptr_op(fwnode, get_parent);
 553}
 554EXPORT_SYMBOL_GPL(fwnode_get_parent);
 555
 556/**
 557 * fwnode_get_next_parent - Iterate to the node's parent
 558 * @fwnode: Firmware whose parent is retrieved
 559 *
 560 * This is like fwnode_get_parent() except that it drops the refcount
 561 * on the passed node, making it suitable for iterating through a
 562 * node's parents.
 563 *
 564 * Returns a node pointer with refcount incremented, use
 565 * fwnode_handle_node() on it when done.
 566 */
 567struct fwnode_handle *fwnode_get_next_parent(struct fwnode_handle *fwnode)
 568{
 569        struct fwnode_handle *parent = fwnode_get_parent(fwnode);
 570
 571        fwnode_handle_put(fwnode);
 572
 573        return parent;
 574}
 575EXPORT_SYMBOL_GPL(fwnode_get_next_parent);
 576
 577/**
 578 * fwnode_get_next_parent_dev - Find device of closest ancestor fwnode
 579 * @fwnode: firmware node
 580 *
 581 * Given a firmware node (@fwnode), this function finds its closest ancestor
 582 * firmware node that has a corresponding struct device and returns that struct
 583 * device.
 584 *
 585 * The caller of this function is expected to call put_device() on the returned
 586 * device when they are done.
 587 */
 588struct device *fwnode_get_next_parent_dev(struct fwnode_handle *fwnode)
 589{
 590        struct device *dev;
 591
 592        fwnode_handle_get(fwnode);
 593        do {
 594                fwnode = fwnode_get_next_parent(fwnode);
 595                if (!fwnode)
 596                        return NULL;
 597                dev = get_dev_from_fwnode(fwnode);
 598        } while (!dev);
 599        fwnode_handle_put(fwnode);
 600        return dev;
 601}
 602
 603/**
 604 * fwnode_count_parents - Return the number of parents a node has
 605 * @fwnode: The node the parents of which are to be counted
 606 *
 607 * Returns the number of parents a node has.
 608 */
 609unsigned int fwnode_count_parents(const struct fwnode_handle *fwnode)
 610{
 611        struct fwnode_handle *__fwnode;
 612        unsigned int count;
 613
 614        __fwnode = fwnode_get_parent(fwnode);
 615
 616        for (count = 0; __fwnode; count++)
 617                __fwnode = fwnode_get_next_parent(__fwnode);
 618
 619        return count;
 620}
 621EXPORT_SYMBOL_GPL(fwnode_count_parents);
 622
 623/**
 624 * fwnode_get_nth_parent - Return an nth parent of a node
 625 * @fwnode: The node the parent of which is requested
 626 * @depth: Distance of the parent from the node
 627 *
 628 * Returns the nth parent of a node. If there is no parent at the requested
 629 * @depth, %NULL is returned. If @depth is 0, the functionality is equivalent to
 630 * fwnode_handle_get(). For @depth == 1, it is fwnode_get_parent() and so on.
 631 *
 632 * The caller is responsible for calling fwnode_handle_put() for the returned
 633 * node.
 634 */
 635struct fwnode_handle *fwnode_get_nth_parent(struct fwnode_handle *fwnode,
 636                                            unsigned int depth)
 637{
 638        unsigned int i;
 639
 640        fwnode_handle_get(fwnode);
 641
 642        for (i = 0; i < depth && fwnode; i++)
 643                fwnode = fwnode_get_next_parent(fwnode);
 644
 645        return fwnode;
 646}
 647EXPORT_SYMBOL_GPL(fwnode_get_nth_parent);
 648
 649/**
 650 * fwnode_is_ancestor_of - Test if @test_ancestor is ancestor of @test_child
 651 * @test_ancestor: Firmware which is tested for being an ancestor
 652 * @test_child: Firmware which is tested for being the child
 653 *
 654 * A node is considered an ancestor of itself too.
 655 *
 656 * Returns true if @test_ancestor is an ancestor of @test_child.
 657 * Otherwise, returns false.
 658 */
 659bool fwnode_is_ancestor_of(struct fwnode_handle *test_ancestor,
 660                                  struct fwnode_handle *test_child)
 661{
 662        if (!test_ancestor)
 663                return false;
 664
 665        fwnode_handle_get(test_child);
 666        while (test_child) {
 667                if (test_child == test_ancestor) {
 668                        fwnode_handle_put(test_child);
 669                        return true;
 670                }
 671                test_child = fwnode_get_next_parent(test_child);
 672        }
 673        return false;
 674}
 675
 676/**
 677 * fwnode_get_next_child_node - Return the next child node handle for a node
 678 * @fwnode: Firmware node to find the next child node for.
 679 * @child: Handle to one of the node's child nodes or a %NULL handle.
 680 */
 681struct fwnode_handle *
 682fwnode_get_next_child_node(const struct fwnode_handle *fwnode,
 683                           struct fwnode_handle *child)
 684{
 685        return fwnode_call_ptr_op(fwnode, get_next_child_node, child);
 686}
 687EXPORT_SYMBOL_GPL(fwnode_get_next_child_node);
 688
 689/**
 690 * fwnode_get_next_available_child_node - Return the next
 691 * available child node handle for a node
 692 * @fwnode: Firmware node to find the next child node for.
 693 * @child: Handle to one of the node's child nodes or a %NULL handle.
 694 */
 695struct fwnode_handle *
 696fwnode_get_next_available_child_node(const struct fwnode_handle *fwnode,
 697                                     struct fwnode_handle *child)
 698{
 699        struct fwnode_handle *next_child = child;
 700
 701        if (!fwnode)
 702                return NULL;
 703
 704        do {
 705                next_child = fwnode_get_next_child_node(fwnode, next_child);
 706                if (!next_child)
 707                        return NULL;
 708        } while (!fwnode_device_is_available(next_child));
 709
 710        return next_child;
 711}
 712EXPORT_SYMBOL_GPL(fwnode_get_next_available_child_node);
 713
 714/**
 715 * device_get_next_child_node - Return the next child node handle for a device
 716 * @dev: Device to find the next child node for.
 717 * @child: Handle to one of the device's child nodes or a null handle.
 718 */
 719struct fwnode_handle *device_get_next_child_node(struct device *dev,
 720                                                 struct fwnode_handle *child)
 721{
 722        const struct fwnode_handle *fwnode = dev_fwnode(dev);
 723        struct fwnode_handle *next;
 724
 725        /* Try to find a child in primary fwnode */
 726        next = fwnode_get_next_child_node(fwnode, child);
 727        if (next)
 728                return next;
 729
 730        /* When no more children in primary, continue with secondary */
 731        if (fwnode && !IS_ERR_OR_NULL(fwnode->secondary))
 732                next = fwnode_get_next_child_node(fwnode->secondary, child);
 733
 734        return next;
 735}
 736EXPORT_SYMBOL_GPL(device_get_next_child_node);
 737
 738/**
 739 * fwnode_get_named_child_node - Return first matching named child node handle
 740 * @fwnode: Firmware node to find the named child node for.
 741 * @childname: String to match child node name against.
 742 */
 743struct fwnode_handle *
 744fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
 745                            const char *childname)
 746{
 747        return fwnode_call_ptr_op(fwnode, get_named_child_node, childname);
 748}
 749EXPORT_SYMBOL_GPL(fwnode_get_named_child_node);
 750
 751/**
 752 * device_get_named_child_node - Return first matching named child node handle
 753 * @dev: Device to find the named child node for.
 754 * @childname: String to match child node name against.
 755 */
 756struct fwnode_handle *device_get_named_child_node(struct device *dev,
 757                                                  const char *childname)
 758{
 759        return fwnode_get_named_child_node(dev_fwnode(dev), childname);
 760}
 761EXPORT_SYMBOL_GPL(device_get_named_child_node);
 762
 763/**
 764 * fwnode_handle_get - Obtain a reference to a device node
 765 * @fwnode: Pointer to the device node to obtain the reference to.
 766 *
 767 * Returns the fwnode handle.
 768 */
 769struct fwnode_handle *fwnode_handle_get(struct fwnode_handle *fwnode)
 770{
 771        if (!fwnode_has_op(fwnode, get))
 772                return fwnode;
 773
 774        return fwnode_call_ptr_op(fwnode, get);
 775}
 776EXPORT_SYMBOL_GPL(fwnode_handle_get);
 777
 778/**
 779 * fwnode_handle_put - Drop reference to a device node
 780 * @fwnode: Pointer to the device node to drop the reference to.
 781 *
 782 * This has to be used when terminating device_for_each_child_node() iteration
 783 * with break or return to prevent stale device node references from being left
 784 * behind.
 785 */
 786void fwnode_handle_put(struct fwnode_handle *fwnode)
 787{
 788        fwnode_call_void_op(fwnode, put);
 789}
 790EXPORT_SYMBOL_GPL(fwnode_handle_put);
 791
 792/**
 793 * fwnode_device_is_available - check if a device is available for use
 794 * @fwnode: Pointer to the fwnode of the device.
 795 *
 796 * For fwnode node types that don't implement the .device_is_available()
 797 * operation, this function returns true.
 798 */
 799bool fwnode_device_is_available(const struct fwnode_handle *fwnode)
 800{
 801        if (!fwnode_has_op(fwnode, device_is_available))
 802                return true;
 803
 804        return fwnode_call_bool_op(fwnode, device_is_available);
 805}
 806EXPORT_SYMBOL_GPL(fwnode_device_is_available);
 807
 808/**
 809 * device_get_child_node_count - return the number of child nodes for device
 810 * @dev: Device to cound the child nodes for
 811 */
 812unsigned int device_get_child_node_count(struct device *dev)
 813{
 814        struct fwnode_handle *child;
 815        unsigned int count = 0;
 816
 817        device_for_each_child_node(dev, child)
 818                count++;
 819
 820        return count;
 821}
 822EXPORT_SYMBOL_GPL(device_get_child_node_count);
 823
 824bool device_dma_supported(struct device *dev)
 825{
 826        const struct fwnode_handle *fwnode = dev_fwnode(dev);
 827
 828        /* For DT, this is always supported.
 829         * For ACPI, this depends on CCA, which
 830         * is determined by the acpi_dma_supported().
 831         */
 832        if (is_of_node(fwnode))
 833                return true;
 834
 835        return acpi_dma_supported(to_acpi_device_node(fwnode));
 836}
 837EXPORT_SYMBOL_GPL(device_dma_supported);
 838
 839enum dev_dma_attr device_get_dma_attr(struct device *dev)
 840{
 841        const struct fwnode_handle *fwnode = dev_fwnode(dev);
 842        enum dev_dma_attr attr = DEV_DMA_NOT_SUPPORTED;
 843
 844        if (is_of_node(fwnode)) {
 845                if (of_dma_is_coherent(to_of_node(fwnode)))
 846                        attr = DEV_DMA_COHERENT;
 847                else
 848                        attr = DEV_DMA_NON_COHERENT;
 849        } else
 850                attr = acpi_get_dma_attr(to_acpi_device_node(fwnode));
 851
 852        return attr;
 853}
 854EXPORT_SYMBOL_GPL(device_get_dma_attr);
 855
 856/**
 857 * fwnode_get_phy_mode - Get phy mode for given firmware node
 858 * @fwnode:     Pointer to the given node
 859 *
 860 * The function gets phy interface string from property 'phy-mode' or
 861 * 'phy-connection-type', and return its index in phy_modes table, or errno in
 862 * error case.
 863 */
 864int fwnode_get_phy_mode(struct fwnode_handle *fwnode)
 865{
 866        const char *pm;
 867        int err, i;
 868
 869        err = fwnode_property_read_string(fwnode, "phy-mode", &pm);
 870        if (err < 0)
 871                err = fwnode_property_read_string(fwnode,
 872                                                  "phy-connection-type", &pm);
 873        if (err < 0)
 874                return err;
 875
 876        for (i = 0; i < PHY_INTERFACE_MODE_MAX; i++)
 877                if (!strcasecmp(pm, phy_modes(i)))
 878                        return i;
 879
 880        return -ENODEV;
 881}
 882EXPORT_SYMBOL_GPL(fwnode_get_phy_mode);
 883
 884/**
 885 * device_get_phy_mode - Get phy mode for given device
 886 * @dev:        Pointer to the given device
 887 *
 888 * The function gets phy interface string from property 'phy-mode' or
 889 * 'phy-connection-type', and return its index in phy_modes table, or errno in
 890 * error case.
 891 */
 892int device_get_phy_mode(struct device *dev)
 893{
 894        return fwnode_get_phy_mode(dev_fwnode(dev));
 895}
 896EXPORT_SYMBOL_GPL(device_get_phy_mode);
 897
 898/**
 899 * fwnode_iomap - Maps the memory mapped IO for a given fwnode
 900 * @fwnode:     Pointer to the firmware node
 901 * @index:      Index of the IO range
 902 *
 903 * Returns a pointer to the mapped memory.
 904 */
 905void __iomem *fwnode_iomap(struct fwnode_handle *fwnode, int index)
 906{
 907        if (IS_ENABLED(CONFIG_OF_ADDRESS) && is_of_node(fwnode))
 908                return of_iomap(to_of_node(fwnode), index);
 909
 910        return NULL;
 911}
 912EXPORT_SYMBOL(fwnode_iomap);
 913
 914/**
 915 * fwnode_irq_get - Get IRQ directly from a fwnode
 916 * @fwnode:     Pointer to the firmware node
 917 * @index:      Zero-based index of the IRQ
 918 *
 919 * Returns Linux IRQ number on success. Other values are determined
 920 * accordingly to acpi_/of_ irq_get() operation.
 921 */
 922int fwnode_irq_get(const struct fwnode_handle *fwnode, unsigned int index)
 923{
 924        struct resource res;
 925        int ret;
 926
 927        if (is_of_node(fwnode))
 928                return of_irq_get(to_of_node(fwnode), index);
 929
 930        ret = acpi_irq_get(ACPI_HANDLE_FWNODE(fwnode), index, &res);
 931        if (ret)
 932                return ret;
 933
 934        return res.start;
 935}
 936EXPORT_SYMBOL(fwnode_irq_get);
 937
 938/**
 939 * fwnode_irq_get_byname - Get IRQ from a fwnode using its name
 940 * @fwnode:     Pointer to the firmware node
 941 * @name:       IRQ name
 942 *
 943 * Description:
 944 * Find a match to the string @name in the 'interrupt-names' string array
 945 * in _DSD for ACPI, or of_node for Device Tree. Then get the Linux IRQ
 946 * number of the IRQ resource corresponding to the index of the matched
 947 * string.
 948 *
 949 * Return:
 950 * Linux IRQ number on success, or negative errno otherwise.
 951 */
 952int fwnode_irq_get_byname(const struct fwnode_handle *fwnode, const char *name)
 953{
 954        int index;
 955
 956        if (!name)
 957                return -EINVAL;
 958
 959        index = fwnode_property_match_string(fwnode, "interrupt-names",  name);
 960        if (index < 0)
 961                return index;
 962
 963        return fwnode_irq_get(fwnode, index);
 964}
 965EXPORT_SYMBOL(fwnode_irq_get_byname);
 966
 967/**
 968 * fwnode_graph_get_next_endpoint - Get next endpoint firmware node
 969 * @fwnode: Pointer to the parent firmware node
 970 * @prev: Previous endpoint node or %NULL to get the first
 971 *
 972 * Returns an endpoint firmware node pointer or %NULL if no more endpoints
 973 * are available.
 974 */
 975struct fwnode_handle *
 976fwnode_graph_get_next_endpoint(const struct fwnode_handle *fwnode,
 977                               struct fwnode_handle *prev)
 978{
 979        const struct fwnode_handle *parent;
 980        struct fwnode_handle *ep;
 981
 982        /*
 983         * If this function is in a loop and the previous iteration returned
 984         * an endpoint from fwnode->secondary, then we need to use the secondary
 985         * as parent rather than @fwnode.
 986         */
 987        if (prev)
 988                parent = fwnode_graph_get_port_parent(prev);
 989        else
 990                parent = fwnode;
 991
 992        ep = fwnode_call_ptr_op(parent, graph_get_next_endpoint, prev);
 993
 994        if (IS_ERR_OR_NULL(ep) &&
 995            !IS_ERR_OR_NULL(parent) && !IS_ERR_OR_NULL(parent->secondary))
 996                ep = fwnode_graph_get_next_endpoint(parent->secondary, NULL);
 997
 998        return ep;
 999}
1000EXPORT_SYMBOL_GPL(fwnode_graph_get_next_endpoint);
1001
1002/**
1003 * fwnode_graph_get_port_parent - Return the device fwnode of a port endpoint
1004 * @endpoint: Endpoint firmware node of the port
1005 *
1006 * Return: the firmware node of the device the @endpoint belongs to.
1007 */
1008struct fwnode_handle *
1009fwnode_graph_get_port_parent(const struct fwnode_handle *endpoint)
1010{
1011        struct fwnode_handle *port, *parent;
1012
1013        port = fwnode_get_parent(endpoint);
1014        parent = fwnode_call_ptr_op(port, graph_get_port_parent);
1015
1016        fwnode_handle_put(port);
1017
1018        return parent;
1019}
1020EXPORT_SYMBOL_GPL(fwnode_graph_get_port_parent);
1021
1022/**
1023 * fwnode_graph_get_remote_port_parent - Return fwnode of a remote device
1024 * @fwnode: Endpoint firmware node pointing to the remote endpoint
1025 *
1026 * Extracts firmware node of a remote device the @fwnode points to.
1027 */
1028struct fwnode_handle *
1029fwnode_graph_get_remote_port_parent(const struct fwnode_handle *fwnode)
1030{
1031        struct fwnode_handle *endpoint, *parent;
1032
1033        endpoint = fwnode_graph_get_remote_endpoint(fwnode);
1034        parent = fwnode_graph_get_port_parent(endpoint);
1035
1036        fwnode_handle_put(endpoint);
1037
1038        return parent;
1039}
1040EXPORT_SYMBOL_GPL(fwnode_graph_get_remote_port_parent);
1041
1042/**
1043 * fwnode_graph_get_remote_port - Return fwnode of a remote port
1044 * @fwnode: Endpoint firmware node pointing to the remote endpoint
1045 *
1046 * Extracts firmware node of a remote port the @fwnode points to.
1047 */
1048struct fwnode_handle *
1049fwnode_graph_get_remote_port(const struct fwnode_handle *fwnode)
1050{
1051        return fwnode_get_next_parent(fwnode_graph_get_remote_endpoint(fwnode));
1052}
1053EXPORT_SYMBOL_GPL(fwnode_graph_get_remote_port);
1054
1055/**
1056 * fwnode_graph_get_remote_endpoint - Return fwnode of a remote endpoint
1057 * @fwnode: Endpoint firmware node pointing to the remote endpoint
1058 *
1059 * Extracts firmware node of a remote endpoint the @fwnode points to.
1060 */
1061struct fwnode_handle *
1062fwnode_graph_get_remote_endpoint(const struct fwnode_handle *fwnode)
1063{
1064        return fwnode_call_ptr_op(fwnode, graph_get_remote_endpoint);
1065}
1066EXPORT_SYMBOL_GPL(fwnode_graph_get_remote_endpoint);
1067
1068static bool fwnode_graph_remote_available(struct fwnode_handle *ep)
1069{
1070        struct fwnode_handle *dev_node;
1071        bool available;
1072
1073        dev_node = fwnode_graph_get_remote_port_parent(ep);
1074        available = fwnode_device_is_available(dev_node);
1075        fwnode_handle_put(dev_node);
1076
1077        return available;
1078}
1079
1080/**
1081 * fwnode_graph_get_endpoint_by_id - get endpoint by port and endpoint numbers
1082 * @fwnode: parent fwnode_handle containing the graph
1083 * @port: identifier of the port node
1084 * @endpoint: identifier of the endpoint node under the port node
1085 * @flags: fwnode lookup flags
1086 *
1087 * Return the fwnode handle of the local endpoint corresponding the port and
1088 * endpoint IDs or NULL if not found.
1089 *
1090 * If FWNODE_GRAPH_ENDPOINT_NEXT is passed in @flags and the specified endpoint
1091 * has not been found, look for the closest endpoint ID greater than the
1092 * specified one and return the endpoint that corresponds to it, if present.
1093 *
1094 * Does not return endpoints that belong to disabled devices or endpoints that
1095 * are unconnected, unless FWNODE_GRAPH_DEVICE_DISABLED is passed in @flags.
1096 *
1097 * The returned endpoint needs to be released by calling fwnode_handle_put() on
1098 * it when it is not needed any more.
1099 */
1100struct fwnode_handle *
1101fwnode_graph_get_endpoint_by_id(const struct fwnode_handle *fwnode,
1102                                u32 port, u32 endpoint, unsigned long flags)
1103{
1104        struct fwnode_handle *ep, *best_ep = NULL;
1105        unsigned int best_ep_id = 0;
1106        bool endpoint_next = flags & FWNODE_GRAPH_ENDPOINT_NEXT;
1107        bool enabled_only = !(flags & FWNODE_GRAPH_DEVICE_DISABLED);
1108
1109        fwnode_graph_for_each_endpoint(fwnode, ep) {
1110                struct fwnode_endpoint fwnode_ep = { 0 };
1111                int ret;
1112
1113                if (enabled_only && !fwnode_graph_remote_available(ep))
1114                        continue;
1115
1116                ret = fwnode_graph_parse_endpoint(ep, &fwnode_ep);
1117                if (ret < 0)
1118                        continue;
1119
1120                if (fwnode_ep.port != port)
1121                        continue;
1122
1123                if (fwnode_ep.id == endpoint)
1124                        return ep;
1125
1126                if (!endpoint_next)
1127                        continue;
1128
1129                /*
1130                 * If the endpoint that has just been found is not the first
1131                 * matching one and the ID of the one found previously is closer
1132                 * to the requested endpoint ID, skip it.
1133                 */
1134                if (fwnode_ep.id < endpoint ||
1135                    (best_ep && best_ep_id < fwnode_ep.id))
1136                        continue;
1137
1138                fwnode_handle_put(best_ep);
1139                best_ep = fwnode_handle_get(ep);
1140                best_ep_id = fwnode_ep.id;
1141        }
1142
1143        return best_ep;
1144}
1145EXPORT_SYMBOL_GPL(fwnode_graph_get_endpoint_by_id);
1146
1147/**
1148 * fwnode_graph_get_endpoint_count - Count endpoints on a device node
1149 * @fwnode: The node related to a device
1150 * @flags: fwnode lookup flags
1151 * Count endpoints in a device node.
1152 *
1153 * If FWNODE_GRAPH_DEVICE_DISABLED flag is specified, also unconnected endpoints
1154 * and endpoints connected to disabled devices are counted.
1155 */
1156unsigned int fwnode_graph_get_endpoint_count(struct fwnode_handle *fwnode,
1157                                             unsigned long flags)
1158{
1159        struct fwnode_handle *ep;
1160        unsigned int count = 0;
1161
1162        fwnode_graph_for_each_endpoint(fwnode, ep) {
1163                if (flags & FWNODE_GRAPH_DEVICE_DISABLED ||
1164                    fwnode_graph_remote_available(ep))
1165                        count++;
1166        }
1167
1168        return count;
1169}
1170EXPORT_SYMBOL_GPL(fwnode_graph_get_endpoint_count);
1171
1172/**
1173 * fwnode_graph_parse_endpoint - parse common endpoint node properties
1174 * @fwnode: pointer to endpoint fwnode_handle
1175 * @endpoint: pointer to the fwnode endpoint data structure
1176 *
1177 * Parse @fwnode representing a graph endpoint node and store the
1178 * information in @endpoint. The caller must hold a reference to
1179 * @fwnode.
1180 */
1181int fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
1182                                struct fwnode_endpoint *endpoint)
1183{
1184        memset(endpoint, 0, sizeof(*endpoint));
1185
1186        return fwnode_call_int_op(fwnode, graph_parse_endpoint, endpoint);
1187}
1188EXPORT_SYMBOL(fwnode_graph_parse_endpoint);
1189
1190const void *device_get_match_data(struct device *dev)
1191{
1192        return fwnode_call_ptr_op(dev_fwnode(dev), device_get_match_data, dev);
1193}
1194EXPORT_SYMBOL_GPL(device_get_match_data);
1195
1196static void *
1197fwnode_graph_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
1198                          void *data, devcon_match_fn_t match)
1199{
1200        struct fwnode_handle *node;
1201        struct fwnode_handle *ep;
1202        void *ret;
1203
1204        fwnode_graph_for_each_endpoint(fwnode, ep) {
1205                node = fwnode_graph_get_remote_port_parent(ep);
1206                if (!fwnode_device_is_available(node)) {
1207                        fwnode_handle_put(node);
1208                        continue;
1209                }
1210
1211                ret = match(node, con_id, data);
1212                fwnode_handle_put(node);
1213                if (ret) {
1214                        fwnode_handle_put(ep);
1215                        return ret;
1216                }
1217        }
1218        return NULL;
1219}
1220
1221static void *
1222fwnode_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
1223                    void *data, devcon_match_fn_t match)
1224{
1225        struct fwnode_handle *node;
1226        void *ret;
1227        int i;
1228
1229        for (i = 0; ; i++) {
1230                node = fwnode_find_reference(fwnode, con_id, i);
1231                if (IS_ERR(node))
1232                        break;
1233
1234                ret = match(node, NULL, data);
1235                fwnode_handle_put(node);
1236                if (ret)
1237                        return ret;
1238        }
1239
1240        return NULL;
1241}
1242
1243/**
1244 * fwnode_connection_find_match - Find connection from a device node
1245 * @fwnode: Device node with the connection
1246 * @con_id: Identifier for the connection
1247 * @data: Data for the match function
1248 * @match: Function to check and convert the connection description
1249 *
1250 * Find a connection with unique identifier @con_id between @fwnode and another
1251 * device node. @match will be used to convert the connection description to
1252 * data the caller is expecting to be returned.
1253 */
1254void *fwnode_connection_find_match(struct fwnode_handle *fwnode,
1255                                   const char *con_id, void *data,
1256                                   devcon_match_fn_t match)
1257{
1258        void *ret;
1259
1260        if (!fwnode || !match)
1261                return NULL;
1262
1263        ret = fwnode_graph_devcon_match(fwnode, con_id, data, match);
1264        if (ret)
1265                return ret;
1266
1267        return fwnode_devcon_match(fwnode, con_id, data, match);
1268}
1269EXPORT_SYMBOL_GPL(fwnode_connection_find_match);
1270