/*
 * Copyright © 2008 Intel Corporation
 *             2014 Red Hat Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 */

#include <drm/drm_atomic_helper.h>
#include <drm/drm_edid.h>
#include <drm/drm_probe_helper.h>

#include "i915_drv.h"
#include "intel_atomic.h"
#include "intel_audio.h"
#include "intel_connector.h"
#include "intel_ddi.h"
#include "intel_display_types.h"
#include "intel_dp.h"
#include "intel_dp_mst.h"
#include "intel_dpio_phy.h"

static int intel_dp_mst_compute_link_config(struct intel_encoder *encoder,
                                            struct intel_crtc_state *crtc_state,
                                            struct drm_connector_state *conn_state,
                                            struct link_config_limits *limits)
{
        struct drm_atomic_state *state = crtc_state->uapi.state;
        struct intel_dp_mst_encoder *intel_mst = enc_to_mst(encoder);
        struct intel_dp *intel_dp = &intel_mst->primary->dp;
        struct intel_connector *connector =
                to_intel_connector(conn_state->connector);
        const struct drm_display_mode *adjusted_mode =
                &crtc_state->hw.adjusted_mode;
        void *port = connector->port;
        bool constant_n = drm_dp_has_quirk(&intel_dp->desc, 0,
                                           DP_DPCD_QUIRK_CONSTANT_N);
        int bpp, slots = -EINVAL;

        crtc_state->lane_count = limits->max_lane_count;
        crtc_state->port_clock = limits->max_clock;

        for (bpp = limits->max_bpp; bpp >= limits->min_bpp; bpp -= 2 * 3) {
                crtc_state->pipe_bpp = bpp;

                crtc_state->pbn = drm_dp_calc_pbn_mode(adjusted_mode->crtc_clock,
                                                       crtc_state->pipe_bpp,
                                                       false);

                slots = drm_dp_atomic_find_vcpi_slots(state, &intel_dp->mst_mgr,
                                                      port, crtc_state->pbn, 0);
                if (slots == -EDEADLK)
                        return slots;
                if (slots >= 0)
                        break;
        }

        if (slots < 0) {
                DRM_DEBUG_KMS("failed finding vcpi slots:%d\n", slots);
                return slots;
        }

        intel_link_compute_m_n(crtc_state->pipe_bpp,
                               crtc_state->lane_count,
                               adjusted_mode->crtc_clock,
                               crtc_state->port_clock,
                               &crtc_state->dp_m_n,
                               constant_n, crtc_state->fec_enable);
        crtc_state->dp_m_n.tu = slots;

        return 0;
}

/*
 * Iterate over all connectors and return the smallest transcoder in the MST
 * stream
 */
static enum transcoder
intel_dp_mst_master_trans_compute(struct intel_atomic_state *state,
                                  struct intel_dp *mst_port)
{
        struct drm_i915_private *dev_priv = to_i915(state->base.dev);
        struct intel_digital_connector_state *conn_state;
        struct intel_connector *connector;
        enum pipe ret = I915_MAX_PIPES;
        int i;

        if (INTEL_GEN(dev_priv) < 12)
                return INVALID_TRANSCODER;

        for_each_new_intel_connector_in_state(state, connector, conn_state, i) {
                struct intel_crtc_state *crtc_state;
                struct intel_crtc *crtc;

                if (connector->mst_port != mst_port || !conn_state->base.crtc)
                        continue;

                crtc = to_intel_crtc(conn_state->base.crtc);
                crtc_state = intel_atomic_get_new_crtc_state(state, crtc);
                if (!crtc_state->uapi.active)
                        continue;

                /*
                 * Using crtc->pipe because crtc_state->cpu_transcoder is
                 * computed, so others CRTCs could have non-computed
                 * cpu_transcoder
                 */
                if (crtc->pipe < ret)
                        ret = crtc->pipe;
        }

        if (ret == I915_MAX_PIPES)
                return INVALID_TRANSCODER;

        /* Simple cast works because TGL don't have a eDP transcoder */
        return (enum transcoder)ret;
}

static int intel_dp_mst_compute_config(struct intel_encoder *encoder,
                                       struct intel_crtc_state *pipe_config,
                                       struct drm_connector_state *conn_state)
{
        struct intel_atomic_state *state = to_intel_atomic_state(conn_state->state);
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dp_mst_encoder *intel_mst = enc_to_mst(encoder);
        struct intel_dp *intel_dp = &intel_mst->primary->dp;
        struct intel_connector *connector =
                to_intel_connector(conn_state->connector);
        struct intel_digital_connector_state *intel_conn_state =
                to_intel_digital_connector_state(conn_state);
        const struct drm_display_mode *adjusted_mode =
                &pipe_config->hw.adjusted_mode;
        void *port = connector->port;
        struct link_config_limits limits;
        int ret;

        if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
                return -EINVAL;

        pipe_config->output_format = INTEL_OUTPUT_FORMAT_RGB;
        pipe_config->has_pch_encoder = false;

        if (intel_conn_state->force_audio == HDMI_AUDIO_AUTO)
                pipe_config->has_audio =
                        drm_dp_mst_port_has_audio(&intel_dp->mst_mgr, port);
        else
                pipe_config->has_audio =
                        intel_conn_state->force_audio == HDMI_AUDIO_ON;

        /*
         * for MST we always configure max link bw - the spec doesn't
         * seem to suggest we should do otherwise.
         */
        limits.min_clock =
        limits.max_clock = intel_dp_max_link_rate(intel_dp);

        limits.min_lane_count =
        limits.max_lane_count = intel_dp_max_lane_count(intel_dp);

        limits.min_bpp = intel_dp_min_bpp(pipe_config);
        /*
         * FIXME: If all the streams can't fit into the link with
         * their current pipe_bpp we should reduce pipe_bpp across
         * the board until things start to fit. Until then we
         * limit to <= 8bpc since that's what was hardcoded for all
         * MST streams previously. This hack should be removed once
         * we have the proper retry logic in place.
         */
        limits.max_bpp = min(pipe_config->pipe_bpp, 24);

        intel_dp_adjust_compliance_config(intel_dp, pipe_config, &limits);

        ret = intel_dp_mst_compute_link_config(encoder, pipe_config,
                                               conn_state, &limits);
        if (ret)
                return ret;

        pipe_config->limited_color_range =
                intel_dp_limited_color_range(pipe_config, conn_state);

        if (IS_GEN9_LP(dev_priv))
                pipe_config->lane_lat_optim_mask =
                        bxt_ddi_phy_calc_lane_lat_optim_mask(pipe_config->lane_count);

        intel_ddi_compute_min_voltage_level(dev_priv, pipe_config);

        pipe_config->mst_master_transcoder = intel_dp_mst_master_trans_compute(state, intel_dp);

        return 0;
}

/*
 * If one of the connectors in a MST stream needs a modeset, mark all CRTCs
 * that shares the same MST stream as mode changed,
 * intel_modeset_pipe_config()+intel_crtc_check_fastset() will take care to do
 * a fastset when possible.
 */
static int
intel_dp_mst_atomic_master_trans_check(struct intel_connector *connector,
                                       struct intel_atomic_state *state)
{
        struct drm_i915_private *dev_priv = to_i915(state->base.dev);
        struct drm_connector_list_iter connector_list_iter;
        struct intel_connector *connector_iter;

        if (INTEL_GEN(dev_priv) < 12)
                return  0;

        if (!intel_connector_needs_modeset(state, &connector->base))
                return 0;

        drm_connector_list_iter_begin(&dev_priv->drm, &connector_list_iter);
        for_each_intel_connector_iter(connector_iter, &connector_list_iter) {
                struct intel_digital_connector_state *conn_iter_state;
                struct intel_crtc_state *crtc_state;
                struct intel_crtc *crtc;
                int ret;

                if (connector_iter->mst_port != connector->mst_port ||
                    connector_iter == connector)
                        continue;

                conn_iter_state = intel_atomic_get_digital_connector_state(state,
                                                                           connector_iter);
                if (IS_ERR(conn_iter_state)) {
                        drm_connector_list_iter_end(&connector_list_iter);
                        return PTR_ERR(conn_iter_state);
                }

                if (!conn_iter_state->base.crtc)
                        continue;

                crtc = to_intel_crtc(conn_iter_state->base.crtc);
                crtc_state = intel_atomic_get_crtc_state(&state->base, crtc);
                if (IS_ERR(crtc_state)) {
                        drm_connector_list_iter_end(&connector_list_iter);
                        return PTR_ERR(crtc_state);
                }

                ret = drm_atomic_add_affected_planes(&state->base, &crtc->base);
                if (ret) {
                        drm_connector_list_iter_end(&connector_list_iter);
                        return ret;
                }
                crtc_state->uapi.mode_changed = true;
        }
        drm_connector_list_iter_end(&connector_list_iter);

        return 0;
}

static int
intel_dp_mst_atomic_check(struct drm_connector *connector,
                          struct drm_atomic_state *_state)
{
        struct intel_atomic_state *state = to_intel_atomic_state(_state);
        struct drm_connector_state *new_conn_state =
                drm_atomic_get_new_connector_state(&state->base, connector);
        struct drm_connector_state *old_conn_state =
                drm_atomic_get_old_connector_state(&state->base, connector);
        struct intel_connector *intel_connector =
                to_intel_connector(connector);
        struct drm_crtc *new_crtc = new_conn_state->crtc;
        struct drm_dp_mst_topology_mgr *mgr;
        int ret;

        ret = intel_digital_connector_atomic_check(connector, &state->base);
        if (ret)
                return ret;

        ret = intel_dp_mst_atomic_master_trans_check(intel_connector, state);
        if (ret)
                return ret;

        if (!old_conn_state->crtc)
                return 0;

        /* We only want to free VCPI if this state disables the CRTC on this
         * connector
         */
        if (new_crtc) {
                struct intel_crtc *intel_crtc = to_intel_crtc(new_crtc);
                struct intel_crtc_state *crtc_state =
                        intel_atomic_get_new_crtc_state(state, intel_crtc);

                if (!crtc_state ||
                    !drm_atomic_crtc_needs_modeset(&crtc_state->uapi) ||
                    crtc_state->uapi.enable)
                        return 0;
        }

        mgr = &enc_to_mst(to_intel_encoder(old_conn_state->best_encoder))->primary->dp.mst_mgr;
        ret = drm_dp_atomic_release_vcpi_slots(&state->base, mgr,
                                               intel_connector->port);

        return ret;
}

static void intel_mst_disable_dp(struct intel_encoder *encoder,
                                 const struct intel_crtc_state *old_crtc_state,
                                 const struct drm_connector_state *old_conn_state)
{
        struct intel_dp_mst_encoder *intel_mst = enc_to_mst(encoder);
        struct intel_digital_port *intel_dig_port = intel_mst->primary;
        struct intel_dp *intel_dp = &intel_dig_port->dp;
        struct intel_connector *connector =
                to_intel_connector(old_conn_state->connector);
        int ret;

        DRM_DEBUG_KMS("active links %d\n", intel_dp->active_mst_links);

        drm_dp_mst_reset_vcpi_slots(&intel_dp->mst_mgr, connector->port);

        ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
        if (ret) {
                DRM_DEBUG_KMS("failed to update payload %d\n", ret);
        }
        if (old_crtc_state->has_audio)
                intel_audio_codec_disable(encoder,
                                          old_crtc_state, old_conn_state);
}

static void intel_mst_post_disable_dp(struct intel_encoder *encoder,
                                      const struct intel_crtc_state *old_crtc_state,
                                      const struct drm_connector_state *old_conn_state)
{
        struct intel_dp_mst_encoder *intel_mst = enc_to_mst(encoder);
        struct intel_digital_port *intel_dig_port = intel_mst->primary;
        struct intel_dp *intel_dp = &intel_dig_port->dp;
        struct intel_connector *connector =
                to_intel_connector(old_conn_state->connector);
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        bool last_mst_stream;
        u32 val;

        intel_dp->active_mst_links--;
        last_mst_stream = intel_dp->active_mst_links == 0;
        drm_WARN_ON(&dev_priv->drm,
                    INTEL_GEN(dev_priv) >= 12 && last_mst_stream &&
                    !intel_dp_mst_is_master_trans(old_crtc_state));

        intel_crtc_vblank_off(old_crtc_state);

        intel_disable_pipe(old_crtc_state);

        drm_dp_update_payload_part2(&intel_dp->mst_mgr);

        val = intel_de_read(dev_priv,
                            TRANS_DDI_FUNC_CTL(old_crtc_state->cpu_transcoder));
        val &= ~TRANS_DDI_DP_VC_PAYLOAD_ALLOC;
        intel_de_write(dev_priv,
                       TRANS_DDI_FUNC_CTL(old_crtc_state->cpu_transcoder),
                       val);

        if (intel_de_wait_for_set(dev_priv, intel_dp->regs.dp_tp_status,
                                  DP_TP_STATUS_ACT_SENT, 1))
                DRM_ERROR("Timed out waiting for ACT sent when disabling\n");
        drm_dp_check_act_status(&intel_dp->mst_mgr);

        drm_dp_mst_deallocate_vcpi(&intel_dp->mst_mgr, connector->port);

        intel_ddi_disable_transcoder_func(old_crtc_state);

        if (INTEL_GEN(dev_priv) >= 9)
                skl_scaler_disable(old_crtc_state);
        else
                ilk_pfit_disable(old_crtc_state);

        /*
         * Power down mst path before disabling the port, otherwise we end
         * up getting interrupts from the sink upon detecting link loss.
         */
        drm_dp_send_power_updown_phy(&intel_dp->mst_mgr, connector->port,
                                     false);
        /*
         * From TGL spec: "If multi-stream slave transcoder: Configure
         * Transcoder Clock Select to direct no clock to the transcoder"
         *
         * From older GENs spec: "Configure Transcoder Clock Select to direct
         * no clock to the transcoder"
         */
        if (INTEL_GEN(dev_priv) < 12 || !last_mst_stream)
                intel_ddi_disable_pipe_clock(old_crtc_state);


        intel_mst->connector = NULL;
        if (last_mst_stream)
                intel_dig_port->base.post_disable(&intel_dig_port->base,
                                                  old_crtc_state, NULL);

        DRM_DEBUG_KMS("active links %d\n", intel_dp->active_mst_links);
}

static void intel_mst_pre_pll_enable_dp(struct intel_encoder *encoder,
                                        const struct intel_crtc_state *pipe_config,
                                        const struct drm_connector_state *conn_state)
{
        struct intel_dp_mst_encoder *intel_mst = enc_to_mst(encoder);
        struct intel_digital_port *intel_dig_port = intel_mst->primary;
        struct intel_dp *intel_dp = &intel_dig_port->dp;

        if (intel_dp->active_mst_links == 0)
                intel_dig_port->base.pre_pll_enable(&intel_dig_port->base,
                                                    pipe_config, NULL);
}

static void intel_mst_pre_enable_dp(struct intel_encoder *encoder,
                                    const struct intel_crtc_state *pipe_config,
                                    const struct drm_connector_state *conn_state)
{
        struct intel_dp_mst_encoder *intel_mst = enc_to_mst(encoder);
        struct intel_digital_port *intel_dig_port = intel_mst->primary;
        struct intel_dp *intel_dp = &intel_dig_port->dp;
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_connector *connector =
                to_intel_connector(conn_state->connector);
        int ret;
        u32 temp;
        bool first_mst_stream;

        /* MST encoders are bound to a crtc, not to a connector,
         * force the mapping here for get_hw_state.
         */
        connector->encoder = encoder;
        intel_mst->connector = connector;
        first_mst_stream = intel_dp->active_mst_links == 0;
        drm_WARN_ON(&dev_priv->drm,
                    INTEL_GEN(dev_priv) >= 12 && first_mst_stream &&
                    !intel_dp_mst_is_master_trans(pipe_config));

        DRM_DEBUG_KMS("active links %d\n", intel_dp->active_mst_links);

        if (first_mst_stream)
                intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);

        drm_dp_send_power_updown_phy(&intel_dp->mst_mgr, connector->port, true);

        if (first_mst_stream)
                intel_dig_port->base.pre_enable(&intel_dig_port->base,
                                                pipe_config, NULL);

        ret = drm_dp_mst_allocate_vcpi(&intel_dp->mst_mgr,
                                       connector->port,
                                       pipe_config->pbn,
                                       pipe_config->dp_m_n.tu);
        if (!ret)
                DRM_ERROR("failed to allocate vcpi\n");

        intel_dp->active_mst_links++;
        temp = intel_de_read(dev_priv, intel_dp->regs.dp_tp_status);
        intel_de_write(dev_priv, intel_dp->regs.dp_tp_status, temp);

        ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);

        /*
         * Before Gen 12 this is not done as part of
         * intel_dig_port->base.pre_enable() and should be done here. For
         * Gen 12+ the step in which this should be done is different for the
         * first MST stream, so it's done on the DDI for the first stream and
         * here for the following ones.
         */
        if (INTEL_GEN(dev_priv) < 12 || !first_mst_stream)
                intel_ddi_enable_pipe_clock(pipe_config);

        intel_ddi_set_dp_msa(pipe_config, conn_state);

        intel_dp_set_m_n(pipe_config, M1_N1);
}

static void intel_mst_enable_dp(struct intel_encoder *encoder,
                                const struct intel_crtc_state *pipe_config,
                                const struct drm_connector_state *conn_state)
{
        struct intel_dp_mst_encoder *intel_mst = enc_to_mst(encoder);
        struct intel_digital_port *intel_dig_port = intel_mst->primary;
        struct intel_dp *intel_dp = &intel_dig_port->dp;
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);

        drm_WARN_ON(&dev_priv->drm, pipe_config->has_pch_encoder);

        intel_enable_pipe(pipe_config);

        intel_crtc_vblank_on(pipe_config);

        DRM_DEBUG_KMS("active links %d\n", intel_dp->active_mst_links);

        if (intel_de_wait_for_set(dev_priv, intel_dp->regs.dp_tp_status,
                                  DP_TP_STATUS_ACT_SENT, 1))
                DRM_ERROR("Timed out waiting for ACT sent\n");

        drm_dp_check_act_status(&intel_dp->mst_mgr);

        drm_dp_update_payload_part2(&intel_dp->mst_mgr);
        if (pipe_config->has_audio)
                intel_audio_codec_enable(encoder, pipe_config, conn_state);
}

static bool intel_dp_mst_enc_get_hw_state(struct intel_encoder *encoder,
                                      enum pipe *pipe)
{
        struct intel_dp_mst_encoder *intel_mst = enc_to_mst(encoder);
        *pipe = intel_mst->pipe;
        if (intel_mst->connector)
                return true;
        return false;
}

static void intel_dp_mst_enc_get_config(struct intel_encoder *encoder,
                                        struct intel_crtc_state *pipe_config)
{
        struct intel_dp_mst_encoder *intel_mst = enc_to_mst(encoder);
        struct intel_digital_port *intel_dig_port = intel_mst->primary;

        intel_ddi_get_config(&intel_dig_port->base, pipe_config);
}

static int intel_dp_mst_get_ddc_modes(struct drm_connector *connector)
{
        struct intel_connector *intel_connector = to_intel_connector(connector);
        struct intel_dp *intel_dp = intel_connector->mst_port;
        struct edid *edid;
        int ret;

        if (drm_connector_is_unregistered(connector))
                return intel_connector_update_modes(connector, NULL);

        edid = drm_dp_mst_get_edid(connector, &intel_dp->mst_mgr, intel_connector->port);
        ret = intel_connector_update_modes(connector, edid);
        kfree(edid);

        return ret;
}

static int
intel_dp_mst_connector_late_register(struct drm_connector *connector)
{
        struct intel_connector *intel_connector = to_intel_connector(connector);
        int ret;

        ret = drm_dp_mst_connector_late_register(connector,
                                                 intel_connector->port);
        if (ret < 0)
                return ret;

        ret = intel_connector_register(connector);
        if (ret < 0)
                drm_dp_mst_connector_early_unregister(connector,
                                                      intel_connector->port);

        return ret;
}

static void
intel_dp_mst_connector_early_unregister(struct drm_connector *connector)
{
        struct intel_connector *intel_connector = to_intel_connector(connector);

        intel_connector_unregister(connector);
        drm_dp_mst_connector_early_unregister(connector,
                                              intel_connector->port);
}

static const struct drm_connector_funcs intel_dp_mst_connector_funcs = {
        .fill_modes = drm_helper_probe_single_connector_modes,
        .atomic_get_property = intel_digital_connector_atomic_get_property,
        .atomic_set_property = intel_digital_connector_atomic_set_property,
        .late_register = intel_dp_mst_connector_late_register,
        .early_unregister = intel_dp_mst_connector_early_unregister,
        .destroy = intel_connector_destroy,
        .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
        .atomic_duplicate_state = intel_digital_connector_duplicate_state,
};

static int intel_dp_mst_get_modes(struct drm_connector *connector)
{
        return intel_dp_mst_get_ddc_modes(connector);
}

static enum drm_mode_status
intel_dp_mst_mode_valid(struct drm_connector *connector,
                        struct drm_display_mode *mode)
{
        struct drm_i915_private *dev_priv = to_i915(connector->dev);
        struct intel_connector *intel_connector = to_intel_connector(connector);
        struct intel_dp *intel_dp = intel_connector->mst_port;
        int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
        int max_rate, mode_rate, max_lanes, max_link_clock;

        if (drm_connector_is_unregistered(connector))
                return MODE_ERROR;

        if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
                return MODE_NO_DBLESCAN;

        max_link_clock = intel_dp_max_link_rate(intel_dp);
        max_lanes = intel_dp_max_lane_count(intel_dp);

        max_rate = intel_dp_max_data_rate(max_link_clock, max_lanes);
        mode_rate = intel_dp_link_required(mode->clock, 18);

        /* TODO - validate mode against available PBN for link */
        if (mode->clock < 10000)
                return MODE_CLOCK_LOW;

        if (mode->flags & DRM_MODE_FLAG_DBLCLK)
                return MODE_H_ILLEGAL;

        if (mode_rate > max_rate || mode->clock > max_dotclk)
                return MODE_CLOCK_HIGH;

        return intel_mode_valid_max_plane_size(dev_priv, mode);
}

static struct drm_encoder *intel_mst_atomic_best_encoder(struct drm_connector *connector,
                                                         struct drm_connector_state *state)
{
        struct intel_connector *intel_connector = to_intel_connector(connector);
        struct intel_dp *intel_dp = intel_connector->mst_port;
        struct intel_crtc *crtc = to_intel_crtc(state->crtc);

        return &intel_dp->mst_encoders[crtc->pipe]->base.base;
}

static int
intel_dp_mst_detect(struct drm_connector *connector,
                    struct drm_modeset_acquire_ctx *ctx, bool force)
{
        struct intel_connector *intel_connector = to_intel_connector(connector);
        struct intel_dp *intel_dp = intel_connector->mst_port;

        if (drm_connector_is_unregistered(connector))
                return connector_status_disconnected;

        return drm_dp_mst_detect_port(connector, ctx, &intel_dp->mst_mgr,
                                      intel_connector->port);
}

static const struct drm_connector_helper_funcs intel_dp_mst_connector_helper_funcs = {
        .get_modes = intel_dp_mst_get_modes,
        .mode_valid = intel_dp_mst_mode_valid,
        .atomic_best_encoder = intel_mst_atomic_best_encoder,
        .atomic_check = intel_dp_mst_atomic_check,
        .detect_ctx = intel_dp_mst_detect,
};

static void intel_dp_mst_encoder_destroy(struct drm_encoder *encoder)
{
        struct intel_dp_mst_encoder *intel_mst = enc_to_mst(to_intel_encoder(encoder));

        drm_encoder_cleanup(encoder);
        kfree(intel_mst);
}

static const struct drm_encoder_funcs intel_dp_mst_enc_funcs = {
        .destroy = intel_dp_mst_encoder_destroy,
};

static bool intel_dp_mst_get_hw_state(struct intel_connector *connector)
{
        if (intel_attached_encoder(connector) && connector->base.state->crtc) {
                enum pipe pipe;
                if (!intel_attached_encoder(connector)->get_hw_state(intel_attached_encoder(connector), &pipe))
                        return false;
                return true;
        }
        return false;
}

static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, const char *pathprop)
{
        struct intel_dp *intel_dp = container_of(mgr, struct intel_dp, mst_mgr);
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        struct drm_device *dev = intel_dig_port->base.base.dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        struct intel_connector *intel_connector;
        struct drm_connector *connector;
        enum pipe pipe;
        int ret;

        intel_connector = intel_connector_alloc();
        if (!intel_connector)
                return NULL;

        intel_connector->get_hw_state = intel_dp_mst_get_hw_state;
        intel_connector->mst_port = intel_dp;
        intel_connector->port = port;
        drm_dp_mst_get_port_malloc(port);

        connector = &intel_connector->base;
        ret = drm_connector_init(dev, connector, &intel_dp_mst_connector_funcs,
                                 DRM_MODE_CONNECTOR_DisplayPort);
        if (ret) {
                intel_connector_free(intel_connector);
                return NULL;
        }

        drm_connector_helper_add(connector, &intel_dp_mst_connector_helper_funcs);

        for_each_pipe(dev_priv, pipe) {
                struct drm_encoder *enc =
                        &intel_dp->mst_encoders[pipe]->base.base;

                ret = drm_connector_attach_encoder(&intel_connector->base, enc);
                if (ret)
                        goto err;
        }

        drm_object_attach_property(&connector->base, dev->mode_config.path_property, 0);
        drm_object_attach_property(&connector->base, dev->mode_config.tile_property, 0);

        ret = drm_connector_set_path_property(connector, pathprop);
        if (ret)
                goto err;

        intel_attach_force_audio_property(connector);
        intel_attach_broadcast_rgb_property(connector);

        /*
         * Reuse the prop from the SST connector because we're
         * not allowed to create new props after device registration.
         */
        connector->max_bpc_property =
                intel_dp->attached_connector->base.max_bpc_property;
        if (connector->max_bpc_property)
                drm_connector_attach_max_bpc_property(connector, 6, 12);

        return connector;

err:
        drm_connector_cleanup(connector);
        return NULL;
}

static const struct drm_dp_mst_topology_cbs mst_cbs = {
        .add_connector = intel_dp_add_mst_connector,
};

static struct intel_dp_mst_encoder *
intel_dp_create_fake_mst_encoder(struct intel_digital_port *intel_dig_port, enum pipe pipe)
{
        struct intel_dp_mst_encoder *intel_mst;
        struct intel_encoder *intel_encoder;
        struct drm_device *dev = intel_dig_port->base.base.dev;

        intel_mst = kzalloc(sizeof(*intel_mst), GFP_KERNEL);

        if (!intel_mst)
                return NULL;

        intel_mst->pipe = pipe;
        intel_encoder = &intel_mst->base;
        intel_mst->primary = intel_dig_port;

        drm_encoder_init(dev, &intel_encoder->base, &intel_dp_mst_enc_funcs,
                         DRM_MODE_ENCODER_DPMST, "DP-MST %c", pipe_name(pipe));

        intel_encoder->type = INTEL_OUTPUT_DP_MST;
        intel_encoder->power_domain = intel_dig_port->base.power_domain;
        intel_encoder->port = intel_dig_port->base.port;
        intel_encoder->cloneable = 0;
        /*
         * This is wrong, but broken userspace uses the intersection
         * of possible_crtcs of all the encoders of a given connector
         * to figure out which crtcs can drive said connector. What
         * should be used instead is the union of possible_crtcs.
         * To keep such userspace functioning we must misconfigure
         * this to make sure the intersection is not empty :(
         */
        intel_encoder->pipe_mask = ~0;

        intel_encoder->compute_config = intel_dp_mst_compute_config;
        intel_encoder->disable = intel_mst_disable_dp;
        intel_encoder->post_disable = intel_mst_post_disable_dp;
        intel_encoder->pre_pll_enable = intel_mst_pre_pll_enable_dp;
        intel_encoder->pre_enable = intel_mst_pre_enable_dp;
        intel_encoder->enable = intel_mst_enable_dp;
        intel_encoder->get_hw_state = intel_dp_mst_enc_get_hw_state;
        intel_encoder->get_config = intel_dp_mst_enc_get_config;

        return intel_mst;

}

static bool
intel_dp_create_fake_mst_encoders(struct intel_digital_port *intel_dig_port)
{
        struct intel_dp *intel_dp = &intel_dig_port->dp;
        struct drm_i915_private *dev_priv = to_i915(intel_dig_port->base.base.dev);
        enum pipe pipe;

        for_each_pipe(dev_priv, pipe)
                intel_dp->mst_encoders[pipe] = intel_dp_create_fake_mst_encoder(intel_dig_port, pipe);
        return true;
}

int
intel_dp_mst_encoder_active_links(struct intel_digital_port *intel_dig_port)
{
        return intel_dig_port->dp.active_mst_links;
}

int
intel_dp_mst_encoder_init(struct intel_digital_port *intel_dig_port, int conn_base_id)
{
        struct drm_i915_private *i915 = to_i915(intel_dig_port->base.base.dev);
        struct intel_dp *intel_dp = &intel_dig_port->dp;
        enum port port = intel_dig_port->base.port;
        int ret;

        if (!HAS_DP_MST(i915) || intel_dp_is_edp(intel_dp))
                return 0;

        if (INTEL_GEN(i915) < 12 && port == PORT_A)
                return 0;

        if (INTEL_GEN(i915) < 11 && port == PORT_E)
                return 0;

        intel_dp->mst_mgr.cbs = &mst_cbs;

        /* create encoders */
        intel_dp_create_fake_mst_encoders(intel_dig_port);
        ret = drm_dp_mst_topology_mgr_init(&intel_dp->mst_mgr, &i915->drm,
                                           &intel_dp->aux, 16, 3, conn_base_id);
        if (ret)
                return ret;

        intel_dp->can_mst = true;

        return 0;
}

void
intel_dp_mst_encoder_cleanup(struct intel_digital_port *intel_dig_port)
{
        struct intel_dp *intel_dp = &intel_dig_port->dp;

        if (!intel_dp->can_mst)
                return;

        drm_dp_mst_topology_mgr_destroy(&intel_dp->mst_mgr);
        /* encoders will get killed by normal cleanup */
}

bool intel_dp_mst_is_master_trans(const struct intel_crtc_state *crtc_state)
{
        return crtc_state->mst_master_transcoder == crtc_state->cpu_transcoder;
}

bool intel_dp_mst_is_slave_trans(const struct intel_crtc_state *crtc_state)
{
        return crtc_state->mst_master_transcoder != INVALID_TRANSCODER &&
               crtc_state->mst_master_transcoder != crtc_state->cpu_transcoder;
}