LXR linux/drivers/staging/greybus/gb-camera.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * Greybus Camera protocol driver.
   4 *
   5 * Copyright 2015 Google Inc.
   6 */
   7#ifndef __GB_CAMERA_H
   8#define __GB_CAMERA_H
   9
  10#include <linux/v4l2-mediabus.h>
  11
  12/* Input flags need to be set from the caller */
  13#define GB_CAMERA_IN_FLAG_TEST          (1 << 0)
  14/* Output flags returned */
  15#define GB_CAMERA_OUT_FLAG_ADJUSTED     (1 << 0)
  16
  17/**
  18 * struct gb_camera_stream - Represents greybus camera stream.
  19 * @width: Stream width in pixels.
  20 * @height: Stream height in pixels.
  21 * @pixel_code: Media bus pixel code.
  22 * @vc: MIPI CSI virtual channel.
  23 * @dt: MIPI CSI data types. Most formats use a single data type, in which case
  24 *      the second element will be ignored.
  25 * @max_size: Maximum size of a frame in bytes. The camera module guarantees
  26 *            that all data between the Frame Start and Frame End packet for
  27 *            the associated virtual channel and data type(s) will not exceed
  28 *            this size.
  29 */
  30struct gb_camera_stream {
  31        unsigned int width;
  32        unsigned int height;
  33        enum v4l2_mbus_pixelcode pixel_code;
  34        unsigned int vc;
  35        unsigned int dt[2];
  36        unsigned int max_size;
  37};
  38
  39/**
  40 * struct gb_camera_csi_params - CSI configuration parameters
  41 * @num_lanes: number of CSI data lanes
  42 * @clk_freq: CSI clock frequency in Hz
  43 */
  44struct gb_camera_csi_params {
  45        unsigned int num_lanes;
  46        unsigned int clk_freq;
  47};
  48
  49/**
  50 * struct gb_camera_ops - Greybus camera operations, used by the Greybus camera
  51 *                        driver to expose operations to the host camera driver.
  52 * @capabilities: Retrieve camera capabilities and store them in the buffer
  53 *                'buf' capabilities. The buffer maximum size is specified by
  54 *                the caller in the 'size' parameter, and the effective
  55 *                capabilities size is returned from the function. If the buffer
  56 *                size is too small to hold the capabilities an error is
  57 *                returned and the buffer is left untouched.
  58 *
  59 * @configure_streams: Negotiate configuration and prepare the module for video
  60 *                     capture. The caller specifies the number of streams it
  61 *                     requests in the 'nstreams' argument and the associated
  62 *                     streams configurations in the 'streams' argument. The
  63 *                     GB_CAMERA_IN_FLAG_TEST 'flag' can be set to test a
  64 *                     configuration without applying it, otherwise the
  65 *                     configuration is applied by the module. The module can
  66 *                     decide to modify the requested configuration, including
  67 *                     using a different number of streams. In that case the
  68 *                     modified configuration won't be applied, the
  69 *                     GB_CAMERA_OUT_FLAG_ADJUSTED 'flag' will be set upon
  70 *                     return, and the modified configuration and number of
  71 *                     streams stored in 'streams' and 'array'. The module
  72 *                     returns its CSI-2 bus parameters in the 'csi_params'
  73 *                     structure in all cases.
  74 *
  75 * @capture: Submit a capture request. The supplied 'request_id' must be unique
  76 *           and higher than the IDs of all the previously submitted requests.
  77 *           The 'streams' argument specifies which streams are affected by the
  78 *           request in the form of a bitmask, with bits corresponding to the
  79 *           configured streams indexes. If the request contains settings, the
  80 *           'settings' argument points to the settings buffer and its size is
  81 *           specified by the 'settings_size' argument. Otherwise the 'settings'
  82 *           argument should be set to NULL and 'settings_size' to 0.
  83 *
  84 * @flush: Flush the capture requests queue. Return the ID of the last request
  85 *         that will processed by the device before it stops transmitting video
  86 *         frames. All queued capture requests with IDs higher than the returned
  87 *         ID will be dropped without being processed.
  88 */
  89struct gb_camera_ops {
  90        ssize_t (*capabilities)(void *priv, char *buf, size_t len);
  91        int (*configure_streams)(void *priv, unsigned int *nstreams,
  92                        unsigned int *flags, struct gb_camera_stream *streams,
  93                        struct gb_camera_csi_params *csi_params);
  94        int (*capture)(void *priv, u32 request_id,
  95                        unsigned int streams, unsigned int num_frames,
  96                        size_t settings_size, const void *settings);
  97        int (*flush)(void *priv, u32 *request_id);
  98};
  99
 100/**
 101 * struct gb_camera_module - Represents greybus camera module.
 102 * @priv: Module private data, passed to all camera operations.
 103 * @ops: Greybus camera operation callbacks.
 104 * @interface_id: Interface id of the module.
 105 * @refcount: Reference counting object.
 106 * @release: Module release function.
 107 * @list: List entry in the camera modules list.
 108 */
 109struct gb_camera_module {
 110        void *priv;
 111        const struct gb_camera_ops *ops;
 112
 113        unsigned int interface_id;
 114        struct kref refcount;
 115        void (*release)(struct kref *kref);
 116        struct list_head list; /* Global list */
 117};
 118
 119#define gb_camera_call(f, op, args...)      \
 120        (!(f) ? -ENODEV : (((f)->ops->op) ?  \
 121        (f)->ops->op((f)->priv, ##args) : -ENOIOCTLCMD))
 122
 123int gb_camera_register(struct gb_camera_module *module);
 124int gb_camera_unregister(struct gb_camera_module *module);
 125
 126#endif /* __GB_CAMERA_H */
 127