include/media/v4l2-fwnode.h

   1 /*
   2  * V4L2 fwnode binding parsing library
   3  *
   4  * Copyright (c) 2016 Intel Corporation.
   5  * Author: Sakari Ailus <sakari.ailus@linux.intel.com>
   6  *
   7  * Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
   8  * Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
   9  *
  10  * Copyright (C) 2012 Renesas Electronics Corp.
  11  * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of version 2 of the GNU General Public License as
  15  * published by the Free Software Foundation.
  16  */
  17 #ifndef _V4L2_FWNODE_H
  18 #define _V4L2_FWNODE_H
  19
  20 #include <linux/errno.h>
  21 #include <linux/fwnode.h>
  22 #include <linux/list.h>
  23 #include <linux/types.h>
  24
  25 #include <media/v4l2-mediabus.h>
  26
  27 struct fwnode_handle;
  28 struct v4l2_async_notifier;
  29 struct v4l2_async_subdev;
  30
  31 #define V4L2_FWNODE_CSI2_MAX_DATA_LANES 4
  32
  33 /**
  34  * struct v4l2_fwnode_bus_mipi_csi2 - MIPI CSI-2 bus data structure
  35  * @flags: media bus (V4L2_MBUS_*) flags
  36  * @data_lanes: an array of physical data lane indexes
  37  * @clock_lane: physical lane index of the clock lane
  38  * @num_data_lanes: number of data lanes
  39  * @lane_polarities: polarity of the lanes. The order is the same of
  40  *                 the physical lanes.
  41  */
  42 struct v4l2_fwnode_bus_mipi_csi2 {
  43         unsigned int flags;
  44         unsigned char data_lanes[V4L2_FWNODE_CSI2_MAX_DATA_LANES];
  45         unsigned char clock_lane;
  46         unsigned short num_data_lanes;
  47         bool lane_polarities[1 + V4L2_FWNODE_CSI2_MAX_DATA_LANES];
  48 };
  49
  50 /**
  51  * struct v4l2_fwnode_bus_parallel - parallel data bus data structure
  52  * @flags: media bus (V4L2_MBUS_*) flags
  53  * @bus_width: bus width in bits
  54  * @data_shift: data shift in bits
  55  */
  56 struct v4l2_fwnode_bus_parallel {
  57         unsigned int flags;
  58         unsigned char bus_width;
  59         unsigned char data_shift;
  60 };
  61
  62 /**
  63  * struct v4l2_fwnode_bus_mipi_csi1 - CSI-1/CCP2 data bus structure
  64  * @clock_inv: polarity of clock/strobe signal
  65  *             false - not inverted, true - inverted
  66  * @strobe: false - data/clock, true - data/strobe
  67  * @lane_polarity: the polarities of the clock (index 0) and data lanes
  68  *                 index (1)
  69  * @data_lane: the number of the data lane
  70  * @clock_lane: the number of the clock lane
  71  */
  72 struct v4l2_fwnode_bus_mipi_csi1 {
  73         bool clock_inv;
  74         bool strobe;
  75         bool lane_polarity[2];
  76         unsigned char data_lane;
  77         unsigned char clock_lane;
  78 };
  79
  80 /**
  81  * struct v4l2_fwnode_endpoint - the endpoint data structure
  82  * @base: fwnode endpoint of the v4l2_fwnode
  83  * @bus_type: bus type
  84  * @bus: bus configuration data structure
  85  * @link_frequencies: array of supported link frequencies
  86  * @nr_of_link_frequencies: number of elements in link_frequenccies array
  87  */
  88 struct v4l2_fwnode_endpoint {
  89         struct fwnode_endpoint base;
  90         /*
  91          * Fields below this line will be zeroed by
  92          * v4l2_fwnode_parse_endpoint()
  93          */
  94         enum v4l2_mbus_type bus_type;
  95         union {
  96                 struct v4l2_fwnode_bus_parallel parallel;
  97                 struct v4l2_fwnode_bus_mipi_csi1 mipi_csi1;
  98                 struct v4l2_fwnode_bus_mipi_csi2 mipi_csi2;
  99         } bus;
 100         u64 *link_frequencies;
 101         unsigned int nr_of_link_frequencies;
 102 };
 103
 104 /**
 105  * struct v4l2_fwnode_link - a link between two endpoints
 106  * @local_node: pointer to device_node of this endpoint
 107  * @local_port: identifier of the port this endpoint belongs to
 108  * @remote_node: pointer to device_node of the remote endpoint
 109  * @remote_port: identifier of the port the remote endpoint belongs to
 110  */
 111 struct v4l2_fwnode_link {
 112         struct fwnode_handle *local_node;
 113         unsigned int local_port;
 114         struct fwnode_handle *remote_node;
 115         unsigned int remote_port;
 116 };
 117
 118 /**
 119  * v4l2_fwnode_endpoint_parse() - parse all fwnode node properties
 120  * @fwnode: pointer to the endpoint's fwnode handle
 121  * @vep: pointer to the V4L2 fwnode data structure
 122  *
 123  * All properties are optional. If none are found, we don't set any flags. This
 124  * means the port has a static configuration and no properties have to be
 125  * specified explicitly. If any properties that identify the bus as parallel
 126  * are found and slave-mode isn't set, we set V4L2_MBUS_MASTER. Similarly, if
 127  * we recognise the bus as serial CSI-2 and clock-noncontinuous isn't set, we
 128  * set the V4L2_MBUS_CSI2_CONTINUOUS_CLOCK flag. The caller should hold a
 129  * reference to @fwnode.
 130  *
 131  * NOTE: This function does not parse properties the size of which is variable
 132  * without a low fixed limit. Please use v4l2_fwnode_endpoint_alloc_parse() in
 133  * new drivers instead.
 134  *
 135  * Return: 0 on success or a negative error code on failure.
 136  */
 137 int v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode,
 138                                struct v4l2_fwnode_endpoint *vep);
 139
 140 /**
 141  * v4l2_fwnode_endpoint_free() - free the V4L2 fwnode acquired by
 142  * v4l2_fwnode_endpoint_alloc_parse()
 143  * @vep: the V4L2 fwnode the resources of which are to be released
 144  *
 145  * It is safe to call this function with NULL argument or on a V4L2 fwnode the
 146  * parsing of which failed.
 147  */
 148 void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep);
 149
 150 /**
 151  * v4l2_fwnode_endpoint_alloc_parse() - parse all fwnode node properties
 152  * @fwnode: pointer to the endpoint's fwnode handle
 153  *
 154  * All properties are optional. If none are found, we don't set any flags. This
 155  * means the port has a static configuration and no properties have to be
 156  * specified explicitly. If any properties that identify the bus as parallel
 157  * are found and slave-mode isn't set, we set V4L2_MBUS_MASTER. Similarly, if
 158  * we recognise the bus as serial CSI-2 and clock-noncontinuous isn't set, we
 159  * set the V4L2_MBUS_CSI2_CONTINUOUS_CLOCK flag. The caller should hold a
 160  * reference to @fwnode.
 161  *
 162  * v4l2_fwnode_endpoint_alloc_parse() has two important differences to
 163  * v4l2_fwnode_endpoint_parse():
 164  *
 165  * 1. It also parses variable size data.
 166  *
 167  * 2. The memory it has allocated to store the variable size data must be freed
 168  *    using v4l2_fwnode_endpoint_free() when no longer needed.
 169  *
 170  * Return: Pointer to v4l2_fwnode_endpoint if successful, on an error pointer
 171  * on error.
 172  */
 173 struct v4l2_fwnode_endpoint *v4l2_fwnode_endpoint_alloc_parse(
 174         struct fwnode_handle *fwnode);
 175
 176 /**
 177  * v4l2_fwnode_parse_link() - parse a link between two endpoints
 178  * @fwnode: pointer to the endpoint's fwnode at the local end of the link
 179  * @link: pointer to the V4L2 fwnode link data structure
 180  *
 181  * Fill the link structure with the local and remote nodes and port numbers.
 182  * The local_node and remote_node fields are set to point to the local and
 183  * remote port's parent nodes respectively (the port parent node being the
 184  * parent node of the port node if that node isn't a 'ports' node, or the
 185  * grand-parent node of the port node otherwise).
 186  *
 187  * A reference is taken to both the local and remote nodes, the caller must use
 188  * v4l2_fwnode_put_link() to drop the references when done with the
 189  * link.
 190  *
 191  * Return: 0 on success, or -ENOLINK if the remote endpoint fwnode can't be
 192  * found.
 193  */
 194 int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode,
 195                            struct v4l2_fwnode_link *link);
 196
 197 /**
 198  * v4l2_fwnode_put_link() - drop references to nodes in a link
 199  * @link: pointer to the V4L2 fwnode link data structure
 200  *
 201  * Drop references to the local and remote nodes in the link. This function
 202  * must be called on every link parsed with v4l2_fwnode_parse_link().
 203  */
 204 void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link);
 205
 206
 207 /**
 208  * typedef parse_endpoint_func - Driver's callback function to be called on
 209  *      each V4L2 fwnode endpoint.
 210  *
 211  * @dev: pointer to &struct device
 212  * @vep: pointer to &struct v4l2_fwnode_endpoint
 213  * @asd: pointer to &struct v4l2_async_subdev
 214  *
 215  * Return:
 216  * * %0 on success
 217  * * %-ENOTCONN if the endpoint is to be skipped but this
 218  *   should not be considered as an error
 219  * * %-EINVAL if the endpoint configuration is invalid
 220  */
 221 typedef int (*parse_endpoint_func)(struct device *dev,
 222                                   struct v4l2_fwnode_endpoint *vep,
 223                                   struct v4l2_async_subdev *asd);
 224
 225
 226 /**
 227  * v4l2_async_notifier_parse_fwnode_endpoints - Parse V4L2 fwnode endpoints in a
 228  *                                              device node
 229  * @dev: the device the endpoints of which are to be parsed
 230  * @notifier: notifier for @dev
 231  * @asd_struct_size: size of the driver's async sub-device struct, including
 232  *                   sizeof(struct v4l2_async_subdev). The &struct
 233  *                   v4l2_async_subdev shall be the first member of
 234  *                   the driver's async sub-device struct, i.e. both
 235  *                   begin at the same memory address.
 236  * @parse_endpoint: Driver's callback function called on each V4L2 fwnode
 237  *                  endpoint. Optional.
 238  *
 239  * Parse the fwnode endpoints of the @dev device and populate the async sub-
 240  * devices array of the notifier. The @parse_endpoint callback function is
 241  * called for each endpoint with the corresponding async sub-device pointer to
 242  * let the caller initialize the driver-specific part of the async sub-device
 243  * structure.
 244  *
 245  * The notifier memory shall be zeroed before this function is called on the
 246  * notifier.
 247  *
 248  * This function may not be called on a registered notifier and may be called on
 249  * a notifier only once.
 250  *
 251  * Do not change the notifier's subdevs array, take references to the subdevs
 252  * array itself or change the notifier's num_subdevs field. This is because this
 253  * function allocates and reallocates the subdevs array based on parsing
 254  * endpoints.
 255  *
 256  * The &struct v4l2_fwnode_endpoint passed to the callback function
 257  * @parse_endpoint is released once the function is finished. If there is a need
 258  * to retain that configuration, the user needs to allocate memory for it.
 259  *
 260  * Any notifier populated using this function must be released with a call to
 261  * v4l2_async_notifier_cleanup() after it has been unregistered and the async
 262  * sub-devices are no longer in use, even if the function returned an error.
 263  *
 264  * Return: %0 on success, including when no async sub-devices are found
 265  *         %-ENOMEM if memory allocation failed
 266  *         %-EINVAL if graph or endpoint parsing failed
 267  *         Other error codes as returned by @parse_endpoint
 268  */
 269 int v4l2_async_notifier_parse_fwnode_endpoints(
 270         struct device *dev, struct v4l2_async_notifier *notifier,
 271         size_t asd_struct_size,
 272         parse_endpoint_func parse_endpoint);
 273
 274 /**
 275  * v4l2_async_notifier_parse_fwnode_endpoints_by_port - Parse V4L2 fwnode
 276  *                                                      endpoints of a port in a
 277  *                                                      device node
 278  * @dev: the device the endpoints of which are to be parsed
 279  * @notifier: notifier for @dev
 280  * @asd_struct_size: size of the driver's async sub-device struct, including
 281  *                   sizeof(struct v4l2_async_subdev). The &struct
 282  *                   v4l2_async_subdev shall be the first member of
 283  *                   the driver's async sub-device struct, i.e. both
 284  *                   begin at the same memory address.
 285  * @port: port number where endpoints are to be parsed
 286  * @parse_endpoint: Driver's callback function called on each V4L2 fwnode
 287  *                  endpoint. Optional.
 288  *
 289  * This function is just like v4l2_async_notifier_parse_fwnode_endpoints() with
 290  * the exception that it only parses endpoints in a given port. This is useful
 291  * on devices that have both sinks and sources: the async sub-devices connected
 292  * to sources have already been configured by another driver (on capture
 293  * devices). In this case the driver must know which ports to parse.
 294  *
 295  * Parse the fwnode endpoints of the @dev device on a given @port and populate
 296  * the async sub-devices array of the notifier. The @parse_endpoint callback
 297  * function is called for each endpoint with the corresponding async sub-device
 298  * pointer to let the caller initialize the driver-specific part of the async
 299  * sub-device structure.
 300  *
 301  * The notifier memory shall be zeroed before this function is called on the
 302  * notifier the first time.
 303  *
 304  * This function may not be called on a registered notifier and may be called on
 305  * a notifier only once per port.
 306  *
 307  * Do not change the notifier's subdevs array, take references to the subdevs
 308  * array itself or change the notifier's num_subdevs field. This is because this
 309  * function allocates and reallocates the subdevs array based on parsing
 310  * endpoints.
 311  *
 312  * The &struct v4l2_fwnode_endpoint passed to the callback function
 313  * @parse_endpoint is released once the function is finished. If there is a need
 314  * to retain that configuration, the user needs to allocate memory for it.
 315  *
 316  * Any notifier populated using this function must be released with a call to
 317  * v4l2_async_notifier_cleanup() after it has been unregistered and the async
 318  * sub-devices are no longer in use, even if the function returned an error.
 319  *
 320  * Return: %0 on success, including when no async sub-devices are found
 321  *         %-ENOMEM if memory allocation failed
 322  *         %-EINVAL if graph or endpoint parsing failed
 323  *         Other error codes as returned by @parse_endpoint
 324  */
 325 int v4l2_async_notifier_parse_fwnode_endpoints_by_port(
 326         struct device *dev, struct v4l2_async_notifier *notifier,
 327         size_t asd_struct_size, unsigned int port,
 328         parse_endpoint_func parse_endpoint);
 329
 330 /**
 331  * v4l2_fwnode_reference_parse_sensor_common - parse common references on
 332  *                                             sensors for async sub-devices
 333  * @dev: the device node the properties of which are parsed for references
 334  * @notifier: the async notifier where the async subdevs will be added
 335  *
 336  * Parse common sensor properties for remote devices related to the
 337  * sensor and set up async sub-devices for them.
 338  *
 339  * Any notifier populated using this function must be released with a call to
 340  * v4l2_async_notifier_release() after it has been unregistered and the async
 341  * sub-devices are no longer in use, even in the case the function returned an
 342  * error.
 343  *
 344  * Return: 0 on success
 345  *         -ENOMEM if memory allocation failed
 346  *         -EINVAL if property parsing failed
 347  */
 348 int v4l2_async_notifier_parse_fwnode_sensor_common(
 349         struct device *dev, struct v4l2_async_notifier *notifier);
 350
 351 #endif /* _V4L2_FWNODE_H */