linux/include/media/v4l2-fwnode.h
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   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 * V4L2 fwnode binding parsing library
   4 *
   5 * Copyright (c) 2016 Intel Corporation.
   6 * Author: Sakari Ailus <sakari.ailus@linux.intel.com>
   7 *
   8 * Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
   9 * Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
  10 *
  11 * Copyright (C) 2012 Renesas Electronics Corp.
  12 * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
  13 */
  14#ifndef _V4L2_FWNODE_H
  15#define _V4L2_FWNODE_H
  16
  17#include <linux/errno.h>
  18#include <linux/fwnode.h>
  19#include <linux/list.h>
  20#include <linux/types.h>
  21
  22#include <media/v4l2-mediabus.h>
  23
  24struct fwnode_handle;
  25struct v4l2_async_notifier;
  26struct v4l2_async_subdev;
  27
  28#define V4L2_FWNODE_CSI2_MAX_DATA_LANES 4
  29
  30/**
  31 * struct v4l2_fwnode_bus_mipi_csi2 - MIPI CSI-2 bus data structure
  32 * @flags: media bus (V4L2_MBUS_*) flags
  33 * @data_lanes: an array of physical data lane indexes
  34 * @clock_lane: physical lane index of the clock lane
  35 * @num_data_lanes: number of data lanes
  36 * @lane_polarities: polarity of the lanes. The order is the same of
  37 *                 the physical lanes.
  38 */
  39struct v4l2_fwnode_bus_mipi_csi2 {
  40        unsigned int flags;
  41        unsigned char data_lanes[V4L2_FWNODE_CSI2_MAX_DATA_LANES];
  42        unsigned char clock_lane;
  43        unsigned short num_data_lanes;
  44        bool lane_polarities[1 + V4L2_FWNODE_CSI2_MAX_DATA_LANES];
  45};
  46
  47/**
  48 * struct v4l2_fwnode_bus_parallel - parallel data bus data structure
  49 * @flags: media bus (V4L2_MBUS_*) flags
  50 * @bus_width: bus width in bits
  51 * @data_shift: data shift in bits
  52 */
  53struct v4l2_fwnode_bus_parallel {
  54        unsigned int flags;
  55        unsigned char bus_width;
  56        unsigned char data_shift;
  57};
  58
  59/**
  60 * struct v4l2_fwnode_bus_mipi_csi1 - CSI-1/CCP2 data bus structure
  61 * @clock_inv: polarity of clock/strobe signal
  62 *             false - not inverted, true - inverted
  63 * @strobe: false - data/clock, true - data/strobe
  64 * @lane_polarity: the polarities of the clock (index 0) and data lanes
  65 *                 index (1)
  66 * @data_lane: the number of the data lane
  67 * @clock_lane: the number of the clock lane
  68 */
  69struct v4l2_fwnode_bus_mipi_csi1 {
  70        unsigned char clock_inv:1;
  71        unsigned char strobe:1;
  72        bool lane_polarity[2];
  73        unsigned char data_lane;
  74        unsigned char clock_lane;
  75};
  76
  77/**
  78 * struct v4l2_fwnode_endpoint - the endpoint data structure
  79 * @base: fwnode endpoint of the v4l2_fwnode
  80 * @bus_type: bus type
  81 * @bus: union with bus configuration data structure
  82 * @bus.parallel: embedded &struct v4l2_fwnode_bus_parallel.
  83 *                Used if the bus is parallel.
  84 * @bus.mipi_csi1: embedded &struct v4l2_fwnode_bus_mipi_csi1.
  85 *                 Used if the bus is MIPI Alliance's Camera Serial
  86 *                 Interface version 1 (MIPI CSI1) or Standard
  87 *                 Mobile Imaging Architecture's Compact Camera Port 2
  88 *                 (SMIA CCP2).
  89 * @bus.mipi_csi2: embedded &struct v4l2_fwnode_bus_mipi_csi2.
  90 *                 Used if the bus is MIPI Alliance's Camera Serial
  91 *                 Interface version 2 (MIPI CSI2).
  92 * @link_frequencies: array of supported link frequencies
  93 * @nr_of_link_frequencies: number of elements in link_frequenccies array
  94 */
  95struct v4l2_fwnode_endpoint {
  96        struct fwnode_endpoint base;
  97        /*
  98         * Fields below this line will be zeroed by
  99         * v4l2_fwnode_endpoint_parse()
 100         */
 101        enum v4l2_mbus_type bus_type;
 102        union {
 103                struct v4l2_fwnode_bus_parallel parallel;
 104                struct v4l2_fwnode_bus_mipi_csi1 mipi_csi1;
 105                struct v4l2_fwnode_bus_mipi_csi2 mipi_csi2;
 106        } bus;
 107        u64 *link_frequencies;
 108        unsigned int nr_of_link_frequencies;
 109};
 110
 111/**
 112 * V4L2_FWNODE_PROPERTY_UNSET - identify a non initialized property
 113 *
 114 * All properties in &struct v4l2_fwnode_device_properties are initialized
 115 * to this value.
 116 */
 117#define V4L2_FWNODE_PROPERTY_UNSET   (-1U)
 118
 119/**
 120 * enum v4l2_fwnode_orientation - possible device orientation
 121 * @V4L2_FWNODE_ORIENTATION_FRONT: device installed on the front side
 122 * @V4L2_FWNODE_ORIENTATION_BACK: device installed on the back side
 123 * @V4L2_FWNODE_ORIENTATION_EXTERNAL: device externally located
 124 */
 125enum v4l2_fwnode_orientation {
 126        V4L2_FWNODE_ORIENTATION_FRONT,
 127        V4L2_FWNODE_ORIENTATION_BACK,
 128        V4L2_FWNODE_ORIENTATION_EXTERNAL
 129};
 130
 131/**
 132 * struct v4l2_fwnode_device_properties - fwnode device properties
 133 * @orientation: device orientation. See &enum v4l2_fwnode_orientation
 134 * @rotation: device rotation
 135 */
 136struct v4l2_fwnode_device_properties {
 137        enum v4l2_fwnode_orientation orientation;
 138        unsigned int rotation;
 139};
 140
 141/**
 142 * struct v4l2_fwnode_link - a link between two endpoints
 143 * @local_node: pointer to device_node of this endpoint
 144 * @local_port: identifier of the port this endpoint belongs to
 145 * @local_id: identifier of the id this endpoint belongs to
 146 * @remote_node: pointer to device_node of the remote endpoint
 147 * @remote_port: identifier of the port the remote endpoint belongs to
 148 * @remote_id: identifier of the id the remote endpoint belongs to
 149 */
 150struct v4l2_fwnode_link {
 151        struct fwnode_handle *local_node;
 152        unsigned int local_port;
 153        unsigned int local_id;
 154        struct fwnode_handle *remote_node;
 155        unsigned int remote_port;
 156        unsigned int remote_id;
 157};
 158
 159/**
 160 * enum v4l2_connector_type - connector type
 161 * @V4L2_CONN_UNKNOWN:   unknown connector type, no V4L2 connector configuration
 162 * @V4L2_CONN_COMPOSITE: analog composite connector
 163 * @V4L2_CONN_SVIDEO:    analog svideo connector
 164 */
 165enum v4l2_connector_type {
 166        V4L2_CONN_UNKNOWN,
 167        V4L2_CONN_COMPOSITE,
 168        V4L2_CONN_SVIDEO,
 169};
 170
 171/**
 172 * struct v4l2_connector_link - connector link data structure
 173 * @head: structure to be used to add the link to the
 174 *        &struct v4l2_fwnode_connector
 175 * @fwnode_link: &struct v4l2_fwnode_link link between the connector and the
 176 *               device the connector belongs to.
 177 */
 178struct v4l2_connector_link {
 179        struct list_head head;
 180        struct v4l2_fwnode_link fwnode_link;
 181};
 182
 183/**
 184 * struct v4l2_fwnode_connector_analog - analog connector data structure
 185 * @sdtv_stds: sdtv standards this connector supports, set to V4L2_STD_ALL
 186 *             if no restrictions are specified.
 187 */
 188struct v4l2_fwnode_connector_analog {
 189        v4l2_std_id sdtv_stds;
 190};
 191
 192/**
 193 * struct v4l2_fwnode_connector - the connector data structure
 194 * @name: the connector device name
 195 * @label: optional connector label
 196 * @type: connector type
 197 * @links: list of all connector &struct v4l2_connector_link links
 198 * @nr_of_links: total number of links
 199 * @connector: connector configuration
 200 * @connector.analog: analog connector configuration
 201 *                    &struct v4l2_fwnode_connector_analog
 202 */
 203struct v4l2_fwnode_connector {
 204        const char *name;
 205        const char *label;
 206        enum v4l2_connector_type type;
 207        struct list_head links;
 208        unsigned int nr_of_links;
 209
 210        union {
 211                struct v4l2_fwnode_connector_analog analog;
 212                /* future connectors */
 213        } connector;
 214};
 215
 216/**
 217 * v4l2_fwnode_endpoint_parse() - parse all fwnode node properties
 218 * @fwnode: pointer to the endpoint's fwnode handle
 219 * @vep: pointer to the V4L2 fwnode data structure
 220 *
 221 * This function parses the V4L2 fwnode endpoint specific parameters from the
 222 * firmware. The caller is responsible for assigning @vep.bus_type to a valid
 223 * media bus type. The caller may also set the default configuration for the
 224 * endpoint --- a configuration that shall be in line with the DT binding
 225 * documentation. Should a device support multiple bus types, the caller may
 226 * call this function once the correct type is found --- with a default
 227 * configuration valid for that type.
 228 *
 229 * As a compatibility means guessing the bus type is also supported by setting
 230 * @vep.bus_type to V4L2_MBUS_UNKNOWN. The caller may not provide a default
 231 * configuration in this case as the defaults are specific to a given bus type.
 232 * This functionality is deprecated and should not be used in new drivers and it
 233 * is only supported for CSI-2 D-PHY, parallel and Bt.656 buses.
 234 *
 235 * The function does not change the V4L2 fwnode endpoint state if it fails.
 236 *
 237 * NOTE: This function does not parse properties the size of which is variable
 238 * without a low fixed limit. Please use v4l2_fwnode_endpoint_alloc_parse() in
 239 * new drivers instead.
 240 *
 241 * Return: %0 on success or a negative error code on failure:
 242 *         %-ENOMEM on memory allocation failure
 243 *         %-EINVAL on parsing failure
 244 *         %-ENXIO on mismatching bus types
 245 */
 246int v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode,
 247                               struct v4l2_fwnode_endpoint *vep);
 248
 249/**
 250 * v4l2_fwnode_endpoint_free() - free the V4L2 fwnode acquired by
 251 * v4l2_fwnode_endpoint_alloc_parse()
 252 * @vep: the V4L2 fwnode the resources of which are to be released
 253 *
 254 * It is safe to call this function with NULL argument or on a V4L2 fwnode the
 255 * parsing of which failed.
 256 */
 257void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep);
 258
 259/**
 260 * v4l2_fwnode_endpoint_alloc_parse() - parse all fwnode node properties
 261 * @fwnode: pointer to the endpoint's fwnode handle
 262 * @vep: pointer to the V4L2 fwnode data structure
 263 *
 264 * This function parses the V4L2 fwnode endpoint specific parameters from the
 265 * firmware. The caller is responsible for assigning @vep.bus_type to a valid
 266 * media bus type. The caller may also set the default configuration for the
 267 * endpoint --- a configuration that shall be in line with the DT binding
 268 * documentation. Should a device support multiple bus types, the caller may
 269 * call this function once the correct type is found --- with a default
 270 * configuration valid for that type.
 271 *
 272 * As a compatibility means guessing the bus type is also supported by setting
 273 * @vep.bus_type to V4L2_MBUS_UNKNOWN. The caller may not provide a default
 274 * configuration in this case as the defaults are specific to a given bus type.
 275 * This functionality is deprecated and should not be used in new drivers and it
 276 * is only supported for CSI-2 D-PHY, parallel and Bt.656 buses.
 277 *
 278 * The function does not change the V4L2 fwnode endpoint state if it fails.
 279 *
 280 * v4l2_fwnode_endpoint_alloc_parse() has two important differences to
 281 * v4l2_fwnode_endpoint_parse():
 282 *
 283 * 1. It also parses variable size data.
 284 *
 285 * 2. The memory it has allocated to store the variable size data must be freed
 286 *    using v4l2_fwnode_endpoint_free() when no longer needed.
 287 *
 288 * Return: %0 on success or a negative error code on failure:
 289 *         %-ENOMEM on memory allocation failure
 290 *         %-EINVAL on parsing failure
 291 *         %-ENXIO on mismatching bus types
 292 */
 293int v4l2_fwnode_endpoint_alloc_parse(struct fwnode_handle *fwnode,
 294                                     struct v4l2_fwnode_endpoint *vep);
 295
 296/**
 297 * v4l2_fwnode_parse_link() - parse a link between two endpoints
 298 * @fwnode: pointer to the endpoint's fwnode at the local end of the link
 299 * @link: pointer to the V4L2 fwnode link data structure
 300 *
 301 * Fill the link structure with the local and remote nodes and port numbers.
 302 * The local_node and remote_node fields are set to point to the local and
 303 * remote port's parent nodes respectively (the port parent node being the
 304 * parent node of the port node if that node isn't a 'ports' node, or the
 305 * grand-parent node of the port node otherwise).
 306 *
 307 * A reference is taken to both the local and remote nodes, the caller must use
 308 * v4l2_fwnode_put_link() to drop the references when done with the
 309 * link.
 310 *
 311 * Return: 0 on success, or -ENOLINK if the remote endpoint fwnode can't be
 312 * found.
 313 */
 314int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode,
 315                           struct v4l2_fwnode_link *link);
 316
 317/**
 318 * v4l2_fwnode_put_link() - drop references to nodes in a link
 319 * @link: pointer to the V4L2 fwnode link data structure
 320 *
 321 * Drop references to the local and remote nodes in the link. This function
 322 * must be called on every link parsed with v4l2_fwnode_parse_link().
 323 */
 324void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link);
 325
 326/**
 327 * v4l2_fwnode_connector_free() - free the V4L2 connector acquired memory
 328 * @connector: the V4L2 connector resources of which are to be released
 329 *
 330 * Free all allocated memory and put all links acquired by
 331 * v4l2_fwnode_connector_parse() and v4l2_fwnode_connector_add_link().
 332 *
 333 * It is safe to call this function with NULL argument or on a V4L2 connector
 334 * the parsing of which failed.
 335 */
 336void v4l2_fwnode_connector_free(struct v4l2_fwnode_connector *connector);
 337
 338/**
 339 * v4l2_fwnode_connector_parse() - initialize the 'struct v4l2_fwnode_connector'
 340 * @fwnode: pointer to the subdev endpoint's fwnode handle where the connector
 341 *          is connected to or to the connector endpoint fwnode handle.
 342 * @connector: pointer to the V4L2 fwnode connector data structure
 343 *
 344 * Fill the &struct v4l2_fwnode_connector with the connector type, label and
 345 * all &enum v4l2_connector_type specific connector data. The label is optional
 346 * so it is set to %NULL if no one was found. The function initialize the links
 347 * to zero. Adding links to the connector is done by calling
 348 * v4l2_fwnode_connector_add_link().
 349 *
 350 * The memory allocated for the label must be freed when no longer needed.
 351 * Freeing the memory is done by v4l2_fwnode_connector_free().
 352 *
 353 * Return:
 354 * * %0 on success or a negative error code on failure:
 355 * * %-EINVAL if @fwnode is invalid
 356 * * %-ENOTCONN if connector type is unknown or connector device can't be found
 357 */
 358int v4l2_fwnode_connector_parse(struct fwnode_handle *fwnode,
 359                                struct v4l2_fwnode_connector *connector);
 360
 361/**
 362 * v4l2_fwnode_connector_add_link - add a link between a connector node and
 363 *                                  a v4l2-subdev node.
 364 * @fwnode: pointer to the subdev endpoint's fwnode handle where the connector
 365 *          is connected to
 366 * @connector: pointer to the V4L2 fwnode connector data structure
 367 *
 368 * Add a new &struct v4l2_connector_link link to the
 369 * &struct v4l2_fwnode_connector connector links list. The link local_node
 370 * points to the connector node, the remote_node to the host v4l2 (sub)dev.
 371 *
 372 * The taken references to remote_node and local_node must be dropped and the
 373 * allocated memory must be freed when no longer needed. Both is done by calling
 374 * v4l2_fwnode_connector_free().
 375 *
 376 * Return:
 377 * * %0 on success or a negative error code on failure:
 378 * * %-EINVAL if @fwnode or @connector is invalid or @connector type is unknown
 379 * * %-ENOMEM on link memory allocation failure
 380 * * %-ENOTCONN if remote connector device can't be found
 381 * * %-ENOLINK if link parsing between v4l2 (sub)dev and connector fails
 382 */
 383int v4l2_fwnode_connector_add_link(struct fwnode_handle *fwnode,
 384                                   struct v4l2_fwnode_connector *connector);
 385
 386/**
 387 * v4l2_fwnode_device_parse() - parse fwnode device properties
 388 * @dev: pointer to &struct device
 389 * @props: pointer to &struct v4l2_fwnode_device_properties where to store the
 390 *         parsed properties values
 391 *
 392 * This function parses and validates the V4L2 fwnode device properties from the
 393 * firmware interface, and fills the @struct v4l2_fwnode_device_properties
 394 * provided by the caller.
 395 *
 396 * Return:
 397 *      % 0 on success
 398 *      %-EINVAL if a parsed property value is not valid
 399 */
 400int v4l2_fwnode_device_parse(struct device *dev,
 401                             struct v4l2_fwnode_device_properties *props);
 402
 403/**
 404 * typedef parse_endpoint_func - Driver's callback function to be called on
 405 *      each V4L2 fwnode endpoint.
 406 *
 407 * @dev: pointer to &struct device
 408 * @vep: pointer to &struct v4l2_fwnode_endpoint
 409 * @asd: pointer to &struct v4l2_async_subdev
 410 *
 411 * Return:
 412 * * %0 on success
 413 * * %-ENOTCONN if the endpoint is to be skipped but this
 414 *   should not be considered as an error
 415 * * %-EINVAL if the endpoint configuration is invalid
 416 */
 417typedef int (*parse_endpoint_func)(struct device *dev,
 418                                  struct v4l2_fwnode_endpoint *vep,
 419                                  struct v4l2_async_subdev *asd);
 420
 421/**
 422 * v4l2_async_notifier_parse_fwnode_endpoints - Parse V4L2 fwnode endpoints in a
 423 *                                              device node
 424 * @dev: the device the endpoints of which are to be parsed
 425 * @notifier: notifier for @dev
 426 * @asd_struct_size: size of the driver's async sub-device struct, including
 427 *                   sizeof(struct v4l2_async_subdev). The &struct
 428 *                   v4l2_async_subdev shall be the first member of
 429 *                   the driver's async sub-device struct, i.e. both
 430 *                   begin at the same memory address.
 431 * @parse_endpoint: Driver's callback function called on each V4L2 fwnode
 432 *                  endpoint. Optional.
 433 *
 434 * Parse the fwnode endpoints of the @dev device and populate the async sub-
 435 * devices list in the notifier. The @parse_endpoint callback function is
 436 * called for each endpoint with the corresponding async sub-device pointer to
 437 * let the caller initialize the driver-specific part of the async sub-device
 438 * structure.
 439 *
 440 * The notifier memory shall be zeroed before this function is called on the
 441 * notifier.
 442 *
 443 * This function may not be called on a registered notifier and may be called on
 444 * a notifier only once.
 445 *
 446 * The &struct v4l2_fwnode_endpoint passed to the callback function
 447 * @parse_endpoint is released once the function is finished. If there is a need
 448 * to retain that configuration, the user needs to allocate memory for it.
 449 *
 450 * Any notifier populated using this function must be released with a call to
 451 * v4l2_async_notifier_cleanup() after it has been unregistered and the async
 452 * sub-devices are no longer in use, even if the function returned an error.
 453 *
 454 * Return: %0 on success, including when no async sub-devices are found
 455 *         %-ENOMEM if memory allocation failed
 456 *         %-EINVAL if graph or endpoint parsing failed
 457 *         Other error codes as returned by @parse_endpoint
 458 */
 459int
 460v4l2_async_notifier_parse_fwnode_endpoints(struct device *dev,
 461                                           struct v4l2_async_notifier *notifier,
 462                                           size_t asd_struct_size,
 463                                           parse_endpoint_func parse_endpoint);
 464
 465/**
 466 * v4l2_async_notifier_parse_fwnode_endpoints_by_port - Parse V4L2 fwnode
 467 *                                                      endpoints of a port in a
 468 *                                                      device node
 469 * @dev: the device the endpoints of which are to be parsed
 470 * @notifier: notifier for @dev
 471 * @asd_struct_size: size of the driver's async sub-device struct, including
 472 *                   sizeof(struct v4l2_async_subdev). The &struct
 473 *                   v4l2_async_subdev shall be the first member of
 474 *                   the driver's async sub-device struct, i.e. both
 475 *                   begin at the same memory address.
 476 * @port: port number where endpoints are to be parsed
 477 * @parse_endpoint: Driver's callback function called on each V4L2 fwnode
 478 *                  endpoint. Optional.
 479 *
 480 * This function is just like v4l2_async_notifier_parse_fwnode_endpoints() with
 481 * the exception that it only parses endpoints in a given port. This is useful
 482 * on devices that have both sinks and sources: the async sub-devices connected
 483 * to sources have already been configured by another driver (on capture
 484 * devices). In this case the driver must know which ports to parse.
 485 *
 486 * Parse the fwnode endpoints of the @dev device on a given @port and populate
 487 * the async sub-devices list of the notifier. The @parse_endpoint callback
 488 * function is called for each endpoint with the corresponding async sub-device
 489 * pointer to let the caller initialize the driver-specific part of the async
 490 * sub-device structure.
 491 *
 492 * The notifier memory shall be zeroed before this function is called on the
 493 * notifier the first time.
 494 *
 495 * This function may not be called on a registered notifier and may be called on
 496 * a notifier only once per port.
 497 *
 498 * The &struct v4l2_fwnode_endpoint passed to the callback function
 499 * @parse_endpoint is released once the function is finished. If there is a need
 500 * to retain that configuration, the user needs to allocate memory for it.
 501 *
 502 * Any notifier populated using this function must be released with a call to
 503 * v4l2_async_notifier_cleanup() after it has been unregistered and the async
 504 * sub-devices are no longer in use, even if the function returned an error.
 505 *
 506 * Return: %0 on success, including when no async sub-devices are found
 507 *         %-ENOMEM if memory allocation failed
 508 *         %-EINVAL if graph or endpoint parsing failed
 509 *         Other error codes as returned by @parse_endpoint
 510 */
 511int
 512v4l2_async_notifier_parse_fwnode_endpoints_by_port(struct device *dev,
 513                                                   struct v4l2_async_notifier *notifier,
 514                                                   size_t asd_struct_size,
 515                                                   unsigned int port,
 516                                                   parse_endpoint_func parse_endpoint);
 517
 518/**
 519 * v4l2_fwnode_reference_parse_sensor_common - parse common references on
 520 *                                             sensors for async sub-devices
 521 * @dev: the device node the properties of which are parsed for references
 522 * @notifier: the async notifier where the async subdevs will be added
 523 *
 524 * Parse common sensor properties for remote devices related to the
 525 * sensor and set up async sub-devices for them.
 526 *
 527 * Any notifier populated using this function must be released with a call to
 528 * v4l2_async_notifier_release() after it has been unregistered and the async
 529 * sub-devices are no longer in use, even in the case the function returned an
 530 * error.
 531 *
 532 * Return: 0 on success
 533 *         -ENOMEM if memory allocation failed
 534 *         -EINVAL if property parsing failed
 535 */
 536int v4l2_async_notifier_parse_fwnode_sensor_common(struct device *dev,
 537                                                   struct v4l2_async_notifier *notifier);
 538
 539/* Helper macros to access the connector links. */
 540
 541/** v4l2_connector_last_link - Helper macro to get the first
 542 *                             &struct v4l2_fwnode_connector link
 543 * @v4l2c: &struct v4l2_fwnode_connector owning the connector links
 544 *
 545 * This marco returns the first added &struct v4l2_connector_link connector
 546 * link or @NULL if the connector has no links.
 547 */
 548#define v4l2_connector_first_link(v4l2c)                                       \
 549        list_first_entry_or_null(&(v4l2c)->links,                              \
 550                                 struct v4l2_connector_link, head)
 551
 552/** v4l2_connector_last_link - Helper macro to get the last
 553 *                             &struct v4l2_fwnode_connector link
 554 * @v4l2c: &struct v4l2_fwnode_connector owning the connector links
 555 *
 556 * This marco returns the last &struct v4l2_connector_link added connector link.
 557 */
 558#define v4l2_connector_last_link(v4l2c)                                        \
 559        list_last_entry(&(v4l2c)->links, struct v4l2_connector_link, head)
 560
 561#endif /* _V4L2_FWNODE_H */
 562