// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2019 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
 */

#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/property.h>
#include <linux/slab.h>

#include <drm/drm_atomic_state_helper.h>
#include <drm/drm_bridge.h>
#include <drm/drm_bridge_connector.h>
#include <drm/drm_connector.h>
#include <drm/drm_device.h>
#include <drm/drm_edid.h>
#include <drm/drm_managed.h>
#include <drm/drm_modeset_helper_vtables.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>
#include <drm/display/drm_hdcp_helper.h>
#include <drm/display/drm_hdmi_audio_helper.h>
#include <drm/display/drm_hdmi_cec_helper.h>
#include <drm/display/drm_hdmi_helper.h>
#include <drm/display/drm_hdmi_state_helper.h>

/**
 * DOC: overview
 *
 * The DRM bridge connector helper object provides a DRM connector
 * implementation that wraps a chain of &struct drm_bridge. The connector
 * operations are fully implemented based on the operations of the bridges in
 * the chain, and don't require any intervention from the display controller
 * driver at runtime.
 *
 * To use the helper, display controller drivers create a bridge connector with
 * a call to drm_bridge_connector_init(). This associates the newly created
 * connector with the chain of bridges passed to the function and registers it
 * with the DRM device. At that point the connector becomes fully usable, no
 * further operation is needed.
 *
 * The DRM bridge connector operations are implemented based on the operations
 * provided by the bridges in the chain. Each connector operation is delegated
 * to the bridge closest to the connector (at the end of the chain) that
 * provides the relevant functionality.
 *
 * To make use of this helper, all bridges in the chain shall report bridge
 * operation flags (&drm_bridge->ops) and bridge output type
 * (&drm_bridge->type), as well as the DRM_BRIDGE_ATTACH_NO_CONNECTOR attach
 * flag (none of the bridges shall create a DRM connector directly).
 */

/**
 * struct drm_bridge_connector - A connector backed by a chain of bridges
 */
struct drm_bridge_connector {
        /**
         * @base: The base DRM connector
         */
        struct drm_connector base;
        /**
         * @encoder:
         *
         * The encoder at the start of the bridges chain.
         */
        struct drm_encoder *encoder;
        /**
         * @bridge_edid:
         *
         * The last bridge in the chain (closest to the connector) that provides
         * EDID read support, if any (see &DRM_BRIDGE_OP_EDID).
         */
        struct drm_bridge *bridge_edid;
        /**
         * @bridge_hpd:
         *
         * The last bridge in the chain (closest to the connector) that provides
         * hot-plug detection notification, if any (see &DRM_BRIDGE_OP_HPD).
         */
        struct drm_bridge *bridge_hpd;
        /**
         * @bridge_detect:
         *
         * The last bridge in the chain (closest to the connector) that provides
         * connector detection, if any (see &DRM_BRIDGE_OP_DETECT).
         */
        struct drm_bridge *bridge_detect;
        /**
         * @bridge_modes:
         *
         * The last bridge in the chain (closest to the connector) that provides
         * connector modes detection, if any (see &DRM_BRIDGE_OP_MODES).
         */
        struct drm_bridge *bridge_modes;
        /**
         * @bridge_hdmi:
         *
         * The bridge in the chain that implements necessary support for the
         * HDMI connector infrastructure, if any (see &DRM_BRIDGE_OP_HDMI).
         */
        struct drm_bridge *bridge_hdmi;
        /**
         * @bridge_hdmi_audio:
         *
         * The bridge in the chain that implements necessary support for the
         * HDMI Audio infrastructure, if any (see &DRM_BRIDGE_OP_HDMI_AUDIO).
         */
        struct drm_bridge *bridge_hdmi_audio;
        /**
         * @bridge_dp_audio:
         *
         * The bridge in the chain that implements necessary support for the
         * DisplayPort Audio infrastructure, if any (see
         * &DRM_BRIDGE_OP_DP_AUDIO).
         */
        struct drm_bridge *bridge_dp_audio;
        /**
         * @bridge_hdmi_cec:
         *
         * The bridge in the chain that implements CEC support, if any (see
         * DRM_BRIDGE_OP_HDMI_CEC_NOTIFIER).
         */
        struct drm_bridge *bridge_hdmi_cec;

        /**
         * @hdmi_funcs:
         *
         * The particular &drm_connector_hdmi_funcs implementation for this
         * bridge connector.
         */
        struct drm_connector_hdmi_funcs hdmi_funcs;
};

#define to_drm_bridge_connector(x) \
        container_of(x, struct drm_bridge_connector, base)

/* -----------------------------------------------------------------------------
 * Bridge Connector Hot-Plug Handling
 */

static void drm_bridge_connector_hpd_notify(struct drm_connector *connector,
                                            enum drm_connector_status status)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);

        /* Notify all bridges in the pipeline of hotplug events. */
        drm_for_each_bridge_in_chain_scoped(bridge_connector->encoder, bridge) {
                if (bridge->funcs->hpd_notify)
                        bridge->funcs->hpd_notify(bridge, connector, status);
        }
}

static void drm_bridge_connector_handle_hpd(struct drm_bridge_connector *drm_bridge_connector,
                                            enum drm_connector_status status)
{
        struct drm_connector *connector = &drm_bridge_connector->base;
        struct drm_device *dev = connector->dev;

        mutex_lock(&dev->mode_config.mutex);
        connector->status = status;
        mutex_unlock(&dev->mode_config.mutex);

        drm_bridge_connector_hpd_notify(connector, status);

        drm_kms_helper_connector_hotplug_event(connector);
}

static void drm_bridge_connector_hpd_cb(void *cb_data,
                                        enum drm_connector_status status)
{
        drm_bridge_connector_handle_hpd(cb_data, status);
}

static void drm_bridge_connector_oob_hotplug_event(struct drm_connector *connector,
                                                   enum drm_connector_status status)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);

        drm_bridge_connector_handle_hpd(bridge_connector, status);
}

static void drm_bridge_connector_enable_hpd(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *hpd = bridge_connector->bridge_hpd;

        if (hpd)
                drm_bridge_hpd_enable(hpd, drm_bridge_connector_hpd_cb,
                                      bridge_connector);
}

static void drm_bridge_connector_disable_hpd(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *hpd = bridge_connector->bridge_hpd;

        if (hpd)
                drm_bridge_hpd_disable(hpd);
}

/* -----------------------------------------------------------------------------
 * Bridge Connector Functions
 */

static enum drm_connector_status
drm_bridge_connector_detect(struct drm_connector *connector, bool force)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *detect = bridge_connector->bridge_detect;
        struct drm_bridge *hdmi = bridge_connector->bridge_hdmi;
        enum drm_connector_status status;

        if (detect) {
                status = detect->funcs->detect(detect, connector);

                if (hdmi)
                        drm_atomic_helper_connector_hdmi_hotplug(connector, status);

                drm_bridge_connector_hpd_notify(connector, status);
        } else {
                switch (connector->connector_type) {
                case DRM_MODE_CONNECTOR_DPI:
                case DRM_MODE_CONNECTOR_LVDS:
                case DRM_MODE_CONNECTOR_DSI:
                case DRM_MODE_CONNECTOR_eDP:
                        status = connector_status_connected;
                        break;
                default:
                        status = connector_status_unknown;
                        break;
                }
        }

        return status;
}

static void drm_bridge_connector_force(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *hdmi = bridge_connector->bridge_hdmi;

        if (hdmi)
                drm_atomic_helper_connector_hdmi_force(connector);
}

static void drm_bridge_connector_debugfs_init(struct drm_connector *connector,
                                              struct dentry *root)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_encoder *encoder = bridge_connector->encoder;
        struct drm_bridge *bridge;

        list_for_each_entry(bridge, &encoder->bridge_chain, chain_node) {
                if (bridge->funcs->debugfs_init)
                        bridge->funcs->debugfs_init(bridge, root);
        }
}

static void drm_bridge_connector_reset(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);

        drm_atomic_helper_connector_reset(connector);
        if (bridge_connector->bridge_hdmi)
                __drm_atomic_helper_connector_hdmi_reset(connector,
                                                         connector->state);
}

static const struct drm_connector_funcs drm_bridge_connector_funcs = {
        .reset = drm_bridge_connector_reset,
        .detect = drm_bridge_connector_detect,
        .force = drm_bridge_connector_force,
        .fill_modes = drm_helper_probe_single_connector_modes,
        .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
        .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
        .debugfs_init = drm_bridge_connector_debugfs_init,
        .oob_hotplug_event = drm_bridge_connector_oob_hotplug_event,
};

/* -----------------------------------------------------------------------------
 * Bridge Connector Helper Functions
 */

static int drm_bridge_connector_get_modes_edid(struct drm_connector *connector,
                                               struct drm_bridge *bridge)
{
        enum drm_connector_status status;
        const struct drm_edid *drm_edid;
        int n;

        status = drm_bridge_connector_detect(connector, false);
        if (status != connector_status_connected)
                goto no_edid;

        drm_edid = drm_bridge_edid_read(bridge, connector);
        if (!drm_edid_valid(drm_edid)) {
                drm_edid_free(drm_edid);
                goto no_edid;
        }

        drm_edid_connector_update(connector, drm_edid);
        n = drm_edid_connector_add_modes(connector);

        drm_edid_free(drm_edid);
        return n;

no_edid:
        drm_edid_connector_update(connector, NULL);
        return 0;
}

static int drm_bridge_connector_get_modes(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        /*
         * If there is a HDMI bridge, EDID has been updated as a part of
         * the .detect(). Just update the modes here.
         */
        bridge = bridge_connector->bridge_hdmi;
        if (bridge)
                return drm_edid_connector_add_modes(connector);

        /*
         * If display exposes EDID, then we parse that in the normal way to
         * build table of supported modes.
         */
        bridge = bridge_connector->bridge_edid;
        if (bridge)
                return drm_bridge_connector_get_modes_edid(connector, bridge);

        /*
         * Otherwise if the display pipeline reports modes (e.g. with a fixed
         * resolution panel or an analog TV output), query it.
         */
        bridge = bridge_connector->bridge_modes;
        if (bridge)
                return bridge->funcs->get_modes(bridge, connector);

        /*
         * We can't retrieve modes, which can happen for instance for a DVI or
         * VGA output with the DDC bus unconnected. The KMS core will add the
         * default modes.
         */
        return 0;
}

static enum drm_mode_status
drm_bridge_connector_mode_valid(struct drm_connector *connector,
                                const struct drm_display_mode *mode)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);

        if (bridge_connector->bridge_hdmi)
                return drm_hdmi_connector_mode_valid(connector, mode);

        return MODE_OK;
}

static int drm_bridge_connector_atomic_check(struct drm_connector *connector,
                                             struct drm_atomic_commit *state)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);

        if (bridge_connector->bridge_hdmi)
                return drm_atomic_helper_connector_hdmi_check(connector, state);

        return 0;
}

static const struct drm_connector_helper_funcs drm_bridge_connector_helper_funcs = {
        .get_modes = drm_bridge_connector_get_modes,
        .mode_valid = drm_bridge_connector_mode_valid,
        .enable_hpd = drm_bridge_connector_enable_hpd,
        .disable_hpd = drm_bridge_connector_disable_hpd,
        .atomic_check = drm_bridge_connector_atomic_check,
};

static enum drm_mode_status
drm_bridge_connector_tmds_char_rate_valid(const struct drm_connector *connector,
                                          const struct drm_display_mode *mode,
                                          unsigned long long tmds_rate)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi;
        if (!bridge)
                return MODE_ERROR;

        if (bridge->funcs->hdmi_tmds_char_rate_valid)
                return bridge->funcs->hdmi_tmds_char_rate_valid(bridge, mode, tmds_rate);
        else
                return MODE_OK;
}

static int drm_bridge_connector_clear_avi_infoframe(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi;
        if (!bridge)
                return -EINVAL;

        return bridge->funcs->hdmi_clear_avi_infoframe(bridge);
}

static int drm_bridge_connector_write_avi_infoframe(struct drm_connector *connector,
                                                    const u8 *buffer, size_t len)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi;
        if (!bridge)
                return -EINVAL;

        return bridge->funcs->hdmi_write_avi_infoframe(bridge, buffer, len);
}

static int drm_bridge_connector_clear_hdmi_infoframe(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi;
        if (!bridge)
                return -EINVAL;

        return bridge->funcs->hdmi_clear_hdmi_infoframe(bridge);
}

static int drm_bridge_connector_write_hdmi_infoframe(struct drm_connector *connector,
                                                     const u8 *buffer, size_t len)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi;
        if (!bridge)
                return -EINVAL;

        return bridge->funcs->hdmi_write_hdmi_infoframe(bridge, buffer, len);
}

static int drm_bridge_connector_clear_audio_infoframe(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi;
        if (!bridge)
                return -EINVAL;

        return bridge->funcs->hdmi_clear_audio_infoframe(bridge);
}

static int drm_bridge_connector_write_audio_infoframe(struct drm_connector *connector,
                                                      const u8 *buffer, size_t len)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi;
        if (!bridge)
                return -EINVAL;

        return bridge->funcs->hdmi_write_audio_infoframe(bridge, buffer, len);
}

static int drm_bridge_connector_clear_hdr_drm_infoframe(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi;
        if (!bridge)
                return -EINVAL;

        return bridge->funcs->hdmi_clear_hdr_drm_infoframe(bridge);
}

static int drm_bridge_connector_write_hdr_drm_infoframe(struct drm_connector *connector,
                                                        const u8 *buffer, size_t len)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi;
        if (!bridge)
                return -EINVAL;

        return bridge->funcs->hdmi_write_hdr_drm_infoframe(bridge, buffer, len);
}

static int drm_bridge_connector_clear_spd_infoframe(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi;
        if (!bridge)
                return -EINVAL;

        return bridge->funcs->hdmi_clear_spd_infoframe(bridge);
}

static int drm_bridge_connector_write_spd_infoframe(struct drm_connector *connector,
                                                    const u8 *buffer, size_t len)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi;
        if (!bridge)
                return -EINVAL;

        return bridge->funcs->hdmi_write_spd_infoframe(bridge, buffer, len);
}

static const struct drm_edid *
drm_bridge_connector_read_edid(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_edid;
        if (!bridge)
                return NULL;

        return drm_bridge_edid_read(bridge, connector);
}

static const struct drm_connector_hdmi_funcs drm_bridge_connector_hdmi_funcs = {
        .tmds_char_rate_valid = drm_bridge_connector_tmds_char_rate_valid,
        .read_edid = drm_bridge_connector_read_edid,
        .avi = {
                .clear_infoframe = drm_bridge_connector_clear_avi_infoframe,
                .write_infoframe = drm_bridge_connector_write_avi_infoframe,
        },
        .hdmi = {
                .clear_infoframe = drm_bridge_connector_clear_hdmi_infoframe,
                .write_infoframe = drm_bridge_connector_write_hdmi_infoframe,
        },
        /* audio, hdr_drm and spd are set dynamically during init */
};

static const struct drm_connector_infoframe_funcs drm_bridge_connector_hdmi_audio_infoframe = {
        .clear_infoframe = drm_bridge_connector_clear_audio_infoframe,
        .write_infoframe = drm_bridge_connector_write_audio_infoframe,
};

static const struct drm_connector_infoframe_funcs drm_bridge_connector_hdmi_hdr_drm_infoframe = {
        .clear_infoframe = drm_bridge_connector_clear_hdr_drm_infoframe,
        .write_infoframe = drm_bridge_connector_write_hdr_drm_infoframe,
};

static const struct drm_connector_infoframe_funcs drm_bridge_connector_hdmi_spd_infoframe = {
        .clear_infoframe = drm_bridge_connector_clear_spd_infoframe,
        .write_infoframe = drm_bridge_connector_write_spd_infoframe,
};

static int drm_bridge_connector_audio_startup(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        if (bridge_connector->bridge_hdmi_audio) {
                bridge = bridge_connector->bridge_hdmi_audio;

                if (!bridge->funcs->hdmi_audio_startup)
                        return 0;

                return bridge->funcs->hdmi_audio_startup(bridge, connector);
        }

        if (bridge_connector->bridge_dp_audio) {
                bridge = bridge_connector->bridge_dp_audio;

                if (!bridge->funcs->dp_audio_startup)
                        return 0;

                return bridge->funcs->dp_audio_startup(bridge, connector);
        }

        return -EINVAL;
}

static int drm_bridge_connector_audio_prepare(struct drm_connector *connector,
                                              struct hdmi_codec_daifmt *fmt,
                                              struct hdmi_codec_params *hparms)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        if (bridge_connector->bridge_hdmi_audio) {
                bridge = bridge_connector->bridge_hdmi_audio;

                return bridge->funcs->hdmi_audio_prepare(bridge, connector, fmt, hparms);
        }

        if (bridge_connector->bridge_dp_audio) {
                bridge = bridge_connector->bridge_dp_audio;

                return bridge->funcs->dp_audio_prepare(bridge, connector, fmt, hparms);
        }

        return -EINVAL;
}

static void drm_bridge_connector_audio_shutdown(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        if (bridge_connector->bridge_hdmi_audio) {
                bridge = bridge_connector->bridge_hdmi_audio;
                bridge->funcs->hdmi_audio_shutdown(bridge, connector);
        }

        if (bridge_connector->bridge_dp_audio) {
                bridge = bridge_connector->bridge_dp_audio;
                bridge->funcs->dp_audio_shutdown(bridge, connector);
        }
}

static int drm_bridge_connector_audio_mute_stream(struct drm_connector *connector,
                                                  bool enable, int direction)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        if (bridge_connector->bridge_hdmi_audio) {
                bridge = bridge_connector->bridge_hdmi_audio;

                if (!bridge->funcs->hdmi_audio_mute_stream)
                        return -ENOTSUPP;

                return bridge->funcs->hdmi_audio_mute_stream(bridge, connector,
                                                             enable, direction);
        }

        if (bridge_connector->bridge_dp_audio) {
                bridge = bridge_connector->bridge_dp_audio;

                if (!bridge->funcs->dp_audio_mute_stream)
                        return -ENOTSUPP;

                return bridge->funcs->dp_audio_mute_stream(bridge, connector,
                                                           enable, direction);
        }

        return -EINVAL;
}

static const struct drm_connector_hdmi_audio_funcs drm_bridge_connector_hdmi_audio_funcs = {
        .startup = drm_bridge_connector_audio_startup,
        .prepare = drm_bridge_connector_audio_prepare,
        .shutdown = drm_bridge_connector_audio_shutdown,
        .mute_stream = drm_bridge_connector_audio_mute_stream,
};

static int drm_bridge_connector_hdmi_cec_enable(struct drm_connector *connector, bool enable)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi_cec;

        return bridge->funcs->hdmi_cec_enable(bridge, enable);
}

static int drm_bridge_connector_hdmi_cec_log_addr(struct drm_connector *connector, u8 logical_addr)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi_cec;

        return bridge->funcs->hdmi_cec_log_addr(bridge, logical_addr);
}

static int drm_bridge_connector_hdmi_cec_transmit(struct drm_connector *connector,
                                                  u8 attempts,
                                                  u32 signal_free_time,
                                                  struct cec_msg *msg)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi_cec;

        return bridge->funcs->hdmi_cec_transmit(bridge, attempts,
                                                signal_free_time,
                                                msg);
}

static int drm_bridge_connector_hdmi_cec_init(struct drm_connector *connector)
{
        struct drm_bridge_connector *bridge_connector =
                to_drm_bridge_connector(connector);
        struct drm_bridge *bridge;

        bridge = bridge_connector->bridge_hdmi_cec;

        if (!bridge->funcs->hdmi_cec_init)
                return 0;

        return bridge->funcs->hdmi_cec_init(bridge, connector);
}

static const struct drm_connector_hdmi_cec_funcs drm_bridge_connector_hdmi_cec_funcs = {
        .init = drm_bridge_connector_hdmi_cec_init,
        .enable = drm_bridge_connector_hdmi_cec_enable,
        .log_addr = drm_bridge_connector_hdmi_cec_log_addr,
        .transmit = drm_bridge_connector_hdmi_cec_transmit,
};

/* -----------------------------------------------------------------------------
 * Bridge Connector Initialisation
 */

static void drm_bridge_connector_put_bridges(struct drm_device *dev, void *data)
{
        struct drm_bridge_connector *bridge_connector = (struct drm_bridge_connector *)data;

        drm_bridge_put(bridge_connector->bridge_edid);
        drm_bridge_put(bridge_connector->bridge_hpd);
        drm_bridge_put(bridge_connector->bridge_detect);
        drm_bridge_put(bridge_connector->bridge_modes);
        drm_bridge_put(bridge_connector->bridge_hdmi);
        drm_bridge_put(bridge_connector->bridge_hdmi_audio);
        drm_bridge_put(bridge_connector->bridge_dp_audio);
        drm_bridge_put(bridge_connector->bridge_hdmi_cec);
}

/**
 * drm_bridge_connector_init - Initialise a connector for a chain of bridges
 * @drm: the DRM device
 * @encoder: the encoder where the bridge chain starts
 *
 * Create a new &drm_bridge_connector for the @drm device. The connector is
 * allocated, initialised, registered with the @drm device and attached to
 * @encoder.
 *
 * The connector is associated with a chain of bridges that starts at
 * the @encoder. All bridges in the chain shall report bridge operation flags
 * (&drm_bridge->ops) and bridge output type (&drm_bridge->type), and none of
 * them may create a DRM connector directly.
 *
 * Returns a pointer to the new connector on success, or a negative error
 * pointer otherwise.
 */
struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
                                                struct drm_encoder *encoder)
{
        struct drm_bridge_connector *bridge_connector;
        struct drm_connector *connector;
        struct i2c_adapter *ddc = NULL;
        struct drm_bridge *panel_bridge __free(drm_bridge_put) = NULL;
        unsigned int supported_formats = BIT(DRM_OUTPUT_COLOR_FORMAT_RGB444);
        unsigned int max_bpc = 8;
        bool support_hdcp = false;
        int connector_type;
        int ret;

        bridge_connector = drmm_kzalloc(drm, sizeof(*bridge_connector), GFP_KERNEL);
        if (!bridge_connector)
                return ERR_PTR(-ENOMEM);

        ret = drmm_add_action(drm, drm_bridge_connector_put_bridges, bridge_connector);
        if (ret)
                return ERR_PTR(ret);

        bridge_connector->encoder = encoder;

        /*
         * TODO: Handle doublescan_allowed and stereo_allowed.
         */
        connector = &bridge_connector->base;
        connector->interlace_allowed = true;
        connector->ycbcr_420_allowed = true;

        /*
         * Initialise connector status handling. First locate the furthest
         * bridges in the pipeline that support HPD and output detection. Then
         * initialise the connector polling mode, using HPD if available and
         * falling back to polling if supported. If neither HPD nor output
         * detection are available, we don't support hotplug detection at all.
         */
        connector_type = DRM_MODE_CONNECTOR_Unknown;
        drm_for_each_bridge_in_chain_scoped(encoder, bridge) {
                if (!bridge->interlace_allowed)
                        connector->interlace_allowed = false;
                if (!bridge->ycbcr_420_allowed)
                        connector->ycbcr_420_allowed = false;

                /*
                 * Ensure the last bridge declares OP_EDID or OP_MODES or both.
                 */
                if (bridge->ops & DRM_BRIDGE_OP_EDID || bridge->ops & DRM_BRIDGE_OP_MODES) {
                        drm_bridge_put(bridge_connector->bridge_edid);
                        bridge_connector->bridge_edid = NULL;
                        drm_bridge_put(bridge_connector->bridge_modes);
                        bridge_connector->bridge_modes = NULL;

                        if (bridge->ops & DRM_BRIDGE_OP_EDID)
                                bridge_connector->bridge_edid = drm_bridge_get(bridge);
                        if (bridge->ops & DRM_BRIDGE_OP_MODES)
                                bridge_connector->bridge_modes = drm_bridge_get(bridge);
                }
                if (bridge->ops & DRM_BRIDGE_OP_HPD) {
                        drm_bridge_put(bridge_connector->bridge_hpd);
                        bridge_connector->bridge_hpd = drm_bridge_get(bridge);
                }
                if (bridge->ops & DRM_BRIDGE_OP_DETECT) {
                        drm_bridge_put(bridge_connector->bridge_detect);
                        bridge_connector->bridge_detect = drm_bridge_get(bridge);
                }
                if (bridge->ops & DRM_BRIDGE_OP_HDMI) {
                        if (bridge_connector->bridge_hdmi)
                                return ERR_PTR(-EBUSY);
                        if (!bridge->funcs->hdmi_write_avi_infoframe ||
                            !bridge->funcs->hdmi_clear_avi_infoframe ||
                            !bridge->funcs->hdmi_write_hdmi_infoframe ||
                            !bridge->funcs->hdmi_clear_hdmi_infoframe)
                                return ERR_PTR(-EINVAL);

                        if (bridge->ops & DRM_BRIDGE_OP_HDMI_AUDIO &&
                            (!bridge->funcs->hdmi_write_audio_infoframe ||
                             !bridge->funcs->hdmi_clear_audio_infoframe))
                                return ERR_PTR(-EINVAL);

                        if (bridge->ops & DRM_BRIDGE_OP_HDMI_HDR_DRM_INFOFRAME &&
                            (!bridge->funcs->hdmi_write_hdr_drm_infoframe ||
                             !bridge->funcs->hdmi_clear_hdr_drm_infoframe))
                                return ERR_PTR(-EINVAL);

                        if (bridge->ops & DRM_BRIDGE_OP_HDMI_SPD_INFOFRAME &&
                            (!bridge->funcs->hdmi_write_spd_infoframe ||
                             !bridge->funcs->hdmi_clear_spd_infoframe))
                                return ERR_PTR(-EINVAL);

                        bridge_connector->bridge_hdmi = drm_bridge_get(bridge);

                        if (bridge->supported_formats)
                                supported_formats = bridge->supported_formats;
                        if (bridge->max_bpc)
                                max_bpc = bridge->max_bpc;
                }

                if (bridge->ops & DRM_BRIDGE_OP_HDMI_AUDIO) {
                        if (bridge_connector->bridge_hdmi_audio)
                                return ERR_PTR(-EBUSY);

                        if (bridge_connector->bridge_dp_audio)
                                return ERR_PTR(-EBUSY);

                        if (!bridge->hdmi_audio_max_i2s_playback_channels &&
                            !bridge->hdmi_audio_spdif_playback)
                                return ERR_PTR(-EINVAL);

                        if (!bridge->funcs->hdmi_audio_prepare ||
                            !bridge->funcs->hdmi_audio_shutdown)
                                return ERR_PTR(-EINVAL);

                        bridge_connector->bridge_hdmi_audio = drm_bridge_get(bridge);
                }

                if (bridge->ops & DRM_BRIDGE_OP_DP_AUDIO) {
                        if (bridge_connector->bridge_dp_audio)
                                return ERR_PTR(-EBUSY);

                        if (bridge_connector->bridge_hdmi_audio)
                                return ERR_PTR(-EBUSY);

                        if (!bridge->hdmi_audio_max_i2s_playback_channels &&
                            !bridge->hdmi_audio_spdif_playback)
                                return ERR_PTR(-EINVAL);

                        if (!bridge->funcs->dp_audio_prepare ||
                            !bridge->funcs->dp_audio_shutdown)
                                return ERR_PTR(-EINVAL);

                        bridge_connector->bridge_dp_audio = drm_bridge_get(bridge);
                }

                if (bridge->ops & DRM_BRIDGE_OP_HDMI_CEC_NOTIFIER) {
                        if (bridge_connector->bridge_hdmi_cec)
                                return ERR_PTR(-EBUSY);

                        bridge_connector->bridge_hdmi_cec = drm_bridge_get(bridge);
                }

                if (bridge->ops & DRM_BRIDGE_OP_HDMI_CEC_ADAPTER) {
                        if (bridge_connector->bridge_hdmi_cec)
                                return ERR_PTR(-EBUSY);

                        bridge_connector->bridge_hdmi_cec = drm_bridge_get(bridge);

                        if (!bridge->funcs->hdmi_cec_enable ||
                            !bridge->funcs->hdmi_cec_log_addr ||
                            !bridge->funcs->hdmi_cec_transmit)
                                return ERR_PTR(-EINVAL);
                }

                if (drm_bridge_is_last(bridge))
                        connector_type = bridge->type;

#ifdef CONFIG_OF
                if (drm_bridge_is_last(bridge) && bridge->of_node)
                        connector->fwnode = fwnode_handle_get(of_fwnode_handle(bridge->of_node));
#endif

                if (bridge->ddc)
                        ddc = bridge->ddc;

                if (drm_bridge_is_panel(bridge)) {
                        drm_bridge_put(panel_bridge);
                        panel_bridge = drm_bridge_get(bridge);
                }

                if (bridge->support_hdcp)
                        support_hdcp = true;
        }

        if (connector_type == DRM_MODE_CONNECTOR_Unknown)
                return ERR_PTR(-EINVAL);

        if (bridge_connector->bridge_hdmi) {
                if (!connector->ycbcr_420_allowed)
                        supported_formats &= ~BIT(DRM_OUTPUT_COLOR_FORMAT_YCBCR420);

                bridge_connector->hdmi_funcs = drm_bridge_connector_hdmi_funcs;

                if (bridge_connector->bridge_hdmi->ops & DRM_BRIDGE_OP_HDMI_AUDIO)
                        bridge_connector->hdmi_funcs.audio =
                                drm_bridge_connector_hdmi_audio_infoframe;

                if (bridge_connector->bridge_hdmi->ops & DRM_BRIDGE_OP_HDMI_HDR_DRM_INFOFRAME)
                        bridge_connector->hdmi_funcs.hdr_drm =
                                drm_bridge_connector_hdmi_hdr_drm_infoframe;

                if (bridge_connector->bridge_hdmi->ops & DRM_BRIDGE_OP_HDMI_SPD_INFOFRAME)
                        bridge_connector->hdmi_funcs.spd =
                                drm_bridge_connector_hdmi_spd_infoframe;

                ret = drmm_connector_hdmi_init(drm, connector,
                                               bridge_connector->bridge_hdmi->vendor,
                                               bridge_connector->bridge_hdmi->product,
                                               &drm_bridge_connector_funcs,
                                               &bridge_connector->hdmi_funcs,
                                               connector_type, ddc,
                                               supported_formats,
                                               max_bpc);
                if (ret)
                        return ERR_PTR(ret);
        } else {
                ret = drmm_connector_init(drm, connector,
                                          &drm_bridge_connector_funcs,
                                          connector_type, ddc);
                if (ret)
                        return ERR_PTR(ret);
        }

        if (bridge_connector->bridge_hdmi_audio ||
            bridge_connector->bridge_dp_audio) {
                struct device *dev;
                struct drm_bridge *bridge;

                if (bridge_connector->bridge_hdmi_audio)
                        bridge = bridge_connector->bridge_hdmi_audio;
                else
                        bridge = bridge_connector->bridge_dp_audio;

                dev = bridge->hdmi_audio_dev;

                ret = drm_connector_hdmi_audio_init(connector, dev,
                                                    &drm_bridge_connector_hdmi_audio_funcs,
                                                    bridge->hdmi_audio_max_i2s_playback_channels,
                                                    bridge->hdmi_audio_i2s_formats,
                                                    bridge->hdmi_audio_spdif_playback,
                                                    bridge->hdmi_audio_dai_port);
                if (ret)
                        return ERR_PTR(ret);
        }

        if (bridge_connector->bridge_hdmi_cec &&
            bridge_connector->bridge_hdmi_cec->ops & DRM_BRIDGE_OP_HDMI_CEC_NOTIFIER) {
                struct drm_bridge *bridge = bridge_connector->bridge_hdmi_cec;

                ret = drmm_connector_hdmi_cec_notifier_register(connector,
                                                                NULL,
                                                                bridge->hdmi_cec_dev);
                if (ret)
                        return ERR_PTR(ret);
        }

        if (bridge_connector->bridge_hdmi_cec &&
            bridge_connector->bridge_hdmi_cec->ops & DRM_BRIDGE_OP_HDMI_CEC_ADAPTER) {
                struct drm_bridge *bridge = bridge_connector->bridge_hdmi_cec;

                ret = drmm_connector_hdmi_cec_register(connector,
                                                       &drm_bridge_connector_hdmi_cec_funcs,
                                                       bridge->hdmi_cec_adapter_name,
                                                       bridge->hdmi_cec_available_las,
                                                       bridge->hdmi_cec_dev);
                if (ret)
                        return ERR_PTR(ret);
        }

        drm_connector_helper_add(connector, &drm_bridge_connector_helper_funcs);

        if (bridge_connector->bridge_hpd)
                connector->polled = DRM_CONNECTOR_POLL_HPD;
        else if (bridge_connector->bridge_detect)
                connector->polled = DRM_CONNECTOR_POLL_CONNECT
                                  | DRM_CONNECTOR_POLL_DISCONNECT;

        if (panel_bridge)
                drm_panel_bridge_set_orientation(connector, panel_bridge);

        if (support_hdcp && IS_REACHABLE(CONFIG_DRM_DISPLAY_HELPER) &&
            IS_ENABLED(CONFIG_DRM_DISPLAY_HDCP_HELPER))
                drm_connector_attach_content_protection_property(connector, true);

        ret = drm_connector_attach_encoder(connector, encoder);
        if (ret)
                return ERR_PTR(ret);

        return connector;
}
EXPORT_SYMBOL_GPL(drm_bridge_connector_init);