// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *      uvc_entity.c  --  USB Video Class driver
 *
 *      Copyright (C) 2005-2011
 *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
 */

#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/videodev2.h>

#include <media/v4l2-common.h>

#include "uvcvideo.h"

static int uvc_mc_create_links(struct uvc_video_chain *chain,
                                    struct uvc_entity *entity)
{
        const u32 flags = MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE;
        struct media_entity *sink;
        unsigned int i;
        int ret;

        sink = (UVC_ENTITY_TYPE(entity) == UVC_TT_STREAMING)
             ? (entity->vdev ? &entity->vdev->entity : NULL)
             : &entity->subdev.entity;
        if (sink == NULL)
                return 0;

        for (i = 0; i < entity->num_pads; ++i) {
                struct media_entity *source;
                struct uvc_entity *remote;
                u8 remote_pad;

                if (!(entity->pads[i].flags & MEDIA_PAD_FL_SINK))
                        continue;

                remote = uvc_entity_by_id(chain->dev, entity->baSourceID[i]);
                if (remote == NULL || remote->num_pads == 0)
                        return -EINVAL;

                source = (UVC_ENTITY_TYPE(remote) == UVC_TT_STREAMING)
                       ? (remote->vdev ? &remote->vdev->entity : NULL)
                       : &remote->subdev.entity;
                if (source == NULL)
                        continue;

                remote_pad = remote->num_pads - 1;
                ret = media_create_pad_link(source, remote_pad,
                                               sink, i, flags);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

static const struct v4l2_subdev_ops uvc_subdev_ops = {
};

void uvc_mc_cleanup_entity(struct uvc_entity *entity)
{
        if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING)
                media_entity_cleanup(&entity->subdev.entity);
        else if (entity->vdev != NULL)
                media_entity_cleanup(&entity->vdev->entity);
}

static int uvc_mc_init_entity(struct uvc_video_chain *chain,
                              struct uvc_entity *entity)
{
        int ret;

        if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING) {
                u32 function;

                v4l2_subdev_init(&entity->subdev, &uvc_subdev_ops);
                strscpy(entity->subdev.name, entity->name,
                        sizeof(entity->subdev.name));

                switch (UVC_ENTITY_TYPE(entity)) {
                case UVC_VC_SELECTOR_UNIT:
                        function = MEDIA_ENT_F_VID_MUX;
                        break;
                case UVC_VC_PROCESSING_UNIT:
                case UVC_VC_EXTENSION_UNIT:
                        /* For lack of a better option. */
                        function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
                        break;
                case UVC_COMPOSITE_CONNECTOR:
                case UVC_COMPONENT_CONNECTOR:
                        function = MEDIA_ENT_F_CONN_COMPOSITE;
                        break;
                case UVC_SVIDEO_CONNECTOR:
                        function = MEDIA_ENT_F_CONN_SVIDEO;
                        break;
                case UVC_ITT_CAMERA:
                        function = MEDIA_ENT_F_CAM_SENSOR;
                        break;
                case UVC_TT_VENDOR_SPECIFIC:
                case UVC_ITT_VENDOR_SPECIFIC:
                case UVC_ITT_MEDIA_TRANSPORT_INPUT:
                case UVC_OTT_VENDOR_SPECIFIC:
                case UVC_OTT_DISPLAY:
                case UVC_OTT_MEDIA_TRANSPORT_OUTPUT:
                case UVC_EXTERNAL_VENDOR_SPECIFIC:
                case UVC_EXT_GPIO_UNIT:
                default:
                        function = MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN;
                        break;
                }

                entity->subdev.entity.function = function;

                ret = media_entity_pads_init(&entity->subdev.entity,
                                        entity->num_pads, entity->pads);

                if (ret < 0)
                        return ret;

                ret = v4l2_device_register_subdev(&chain->dev->vdev,
                                                  &entity->subdev);
        } else if (entity->vdev != NULL) {
                ret = media_entity_pads_init(&entity->vdev->entity,
                                        entity->num_pads, entity->pads);
                if (entity->flags & UVC_ENTITY_FLAG_DEFAULT)
                        entity->vdev->entity.flags |= MEDIA_ENT_FL_DEFAULT;
        } else
                ret = 0;

        return ret;
}

int uvc_mc_register_entities(struct uvc_video_chain *chain)
{
        struct uvc_entity *entity;
        int ret;

        list_for_each_entry(entity, &chain->entities, chain) {
                ret = uvc_mc_init_entity(chain, entity);
                if (ret < 0) {
                        dev_info(&chain->dev->intf->dev,
                                 "Failed to initialize entity for entity %u\n",
                                 entity->id);
                        return ret;
                }
        }

        list_for_each_entry(entity, &chain->entities, chain) {
                ret = uvc_mc_create_links(chain, entity);
                if (ret < 0) {
                        dev_info(&chain->dev->intf->dev,
                                 "Failed to create links for entity %u\n",
                                 entity->id);
                        return ret;
                }
        }

        return 0;
}