/*
 * Copyright © 2014 Intel Corporation
 *
 * 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 <linux/kernel.h>
#include <linux/component.h>
#include <drm/i915_component.h>
#include <drm/intel_lpe_audio.h>
#include "intel_drv.h"

#include <drm/drmP.h>
#include <drm/drm_edid.h>
#include "i915_drv.h"

/**
 * DOC: High Definition Audio over HDMI and Display Port
 *
 * The graphics and audio drivers together support High Definition Audio over
 * HDMI and Display Port. The audio programming sequences are divided into audio
 * codec and controller enable and disable sequences. The graphics driver
 * handles the audio codec sequences, while the audio driver handles the audio
 * controller sequences.
 *
 * The disable sequences must be performed before disabling the transcoder or
 * port. The enable sequences may only be performed after enabling the
 * transcoder and port, and after completed link training. Therefore the audio
 * enable/disable sequences are part of the modeset sequence.
 *
 * The codec and controller sequences could be done either parallel or serial,
 * but generally the ELDV/PD change in the codec sequence indicates to the audio
 * driver that the controller sequence should start. Indeed, most of the
 * co-operation between the graphics and audio drivers is handled via audio
 * related registers. (The notable exception is the power management, not
 * covered here.)
 *
 * The struct &i915_audio_component is used to interact between the graphics
 * and audio drivers. The struct &i915_audio_component_ops @ops in it is
 * defined in graphics driver and called in audio driver. The
 * struct &i915_audio_component_audio_ops @audio_ops is called from i915 driver.
 */

/* DP N/M table */
#define LC_540M 540000
#define LC_270M 270000
#define LC_162M 162000

struct dp_aud_n_m {
        int sample_rate;
        int clock;
        u16 m;
        u16 n;
};

/* Values according to DP 1.4 Table 2-104 */
static const struct dp_aud_n_m dp_aud_n_m[] = {
        { 32000, LC_162M, 1024, 10125 },
        { 44100, LC_162M, 784, 5625 },
        { 48000, LC_162M, 512, 3375 },
        { 64000, LC_162M, 2048, 10125 },
        { 88200, LC_162M, 1568, 5625 },
        { 96000, LC_162M, 1024, 3375 },
        { 128000, LC_162M, 4096, 10125 },
        { 176400, LC_162M, 3136, 5625 },
        { 192000, LC_162M, 2048, 3375 },
        { 32000, LC_270M, 1024, 16875 },
        { 44100, LC_270M, 784, 9375 },
        { 48000, LC_270M, 512, 5625 },
        { 64000, LC_270M, 2048, 16875 },
        { 88200, LC_270M, 1568, 9375 },
        { 96000, LC_270M, 1024, 5625 },
        { 128000, LC_270M, 4096, 16875 },
        { 176400, LC_270M, 3136, 9375 },
        { 192000, LC_270M, 2048, 5625 },
        { 32000, LC_540M, 1024, 33750 },
        { 44100, LC_540M, 784, 18750 },
        { 48000, LC_540M, 512, 11250 },
        { 64000, LC_540M, 2048, 33750 },
        { 88200, LC_540M, 1568, 18750 },
        { 96000, LC_540M, 1024, 11250 },
        { 128000, LC_540M, 4096, 33750 },
        { 176400, LC_540M, 3136, 18750 },
        { 192000, LC_540M, 2048, 11250 },
};

static const struct dp_aud_n_m *
audio_config_dp_get_n_m(const struct intel_crtc_state *crtc_state, int rate)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(dp_aud_n_m); i++) {
                if (rate == dp_aud_n_m[i].sample_rate &&
                    crtc_state->port_clock == dp_aud_n_m[i].clock)
                        return &dp_aud_n_m[i];
        }

        return NULL;
}

static const struct {
        int clock;
        u32 config;
} hdmi_audio_clock[] = {
        { 25175, AUD_CONFIG_PIXEL_CLOCK_HDMI_25175 },
        { 25200, AUD_CONFIG_PIXEL_CLOCK_HDMI_25200 }, /* default per bspec */
        { 27000, AUD_CONFIG_PIXEL_CLOCK_HDMI_27000 },
        { 27027, AUD_CONFIG_PIXEL_CLOCK_HDMI_27027 },
        { 54000, AUD_CONFIG_PIXEL_CLOCK_HDMI_54000 },
        { 54054, AUD_CONFIG_PIXEL_CLOCK_HDMI_54054 },
        { 74176, AUD_CONFIG_PIXEL_CLOCK_HDMI_74176 },
        { 74250, AUD_CONFIG_PIXEL_CLOCK_HDMI_74250 },
        { 148352, AUD_CONFIG_PIXEL_CLOCK_HDMI_148352 },
        { 148500, AUD_CONFIG_PIXEL_CLOCK_HDMI_148500 },
};

/* HDMI N/CTS table */
#define TMDS_297M 297000
#define TMDS_296M 296703
static const struct {
        int sample_rate;
        int clock;
        int n;
        int cts;
} hdmi_aud_ncts[] = {
        { 44100, TMDS_296M, 4459, 234375 },
        { 44100, TMDS_297M, 4704, 247500 },
        { 48000, TMDS_296M, 5824, 281250 },
        { 48000, TMDS_297M, 5120, 247500 },
        { 32000, TMDS_296M, 5824, 421875 },
        { 32000, TMDS_297M, 3072, 222750 },
        { 88200, TMDS_296M, 8918, 234375 },
        { 88200, TMDS_297M, 9408, 247500 },
        { 96000, TMDS_296M, 11648, 281250 },
        { 96000, TMDS_297M, 10240, 247500 },
        { 176400, TMDS_296M, 17836, 234375 },
        { 176400, TMDS_297M, 18816, 247500 },
        { 192000, TMDS_296M, 23296, 281250 },
        { 192000, TMDS_297M, 20480, 247500 },
};

/* get AUD_CONFIG_PIXEL_CLOCK_HDMI_* value for mode */
static u32 audio_config_hdmi_pixel_clock(const struct intel_crtc_state *crtc_state)
{
        const struct drm_display_mode *adjusted_mode =
                &crtc_state->base.adjusted_mode;
        int i;

        for (i = 0; i < ARRAY_SIZE(hdmi_audio_clock); i++) {
                if (adjusted_mode->crtc_clock == hdmi_audio_clock[i].clock)
                        break;
        }

        if (i == ARRAY_SIZE(hdmi_audio_clock)) {
                DRM_DEBUG_KMS("HDMI audio pixel clock setting for %d not found, falling back to defaults\n",
                              adjusted_mode->crtc_clock);
                i = 1;
        }

        DRM_DEBUG_KMS("Configuring HDMI audio for pixel clock %d (0x%08x)\n",
                      hdmi_audio_clock[i].clock,
                      hdmi_audio_clock[i].config);

        return hdmi_audio_clock[i].config;
}

static int audio_config_hdmi_get_n(const struct intel_crtc_state *crtc_state,
                                   int rate)
{
        const struct drm_display_mode *adjusted_mode =
                &crtc_state->base.adjusted_mode;
        int i;

        for (i = 0; i < ARRAY_SIZE(hdmi_aud_ncts); i++) {
                if (rate == hdmi_aud_ncts[i].sample_rate &&
                    adjusted_mode->crtc_clock == hdmi_aud_ncts[i].clock) {
                        return hdmi_aud_ncts[i].n;
                }
        }
        return 0;
}

static bool intel_eld_uptodate(struct drm_connector *connector,
                               i915_reg_t reg_eldv, uint32_t bits_eldv,
                               i915_reg_t reg_elda, uint32_t bits_elda,
                               i915_reg_t reg_edid)
{
        struct drm_i915_private *dev_priv = to_i915(connector->dev);
        uint8_t *eld = connector->eld;
        uint32_t tmp;
        int i;

        tmp = I915_READ(reg_eldv);
        tmp &= bits_eldv;

        if (!tmp)
                return false;

        tmp = I915_READ(reg_elda);
        tmp &= ~bits_elda;
        I915_WRITE(reg_elda, tmp);

        for (i = 0; i < drm_eld_size(eld) / 4; i++)
                if (I915_READ(reg_edid) != *((uint32_t *)eld + i))
                        return false;

        return true;
}

static void g4x_audio_codec_disable(struct intel_encoder *encoder,
                                    const struct intel_crtc_state *old_crtc_state,
                                    const struct drm_connector_state *old_conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        uint32_t eldv, tmp;

        DRM_DEBUG_KMS("Disable audio codec\n");

        tmp = I915_READ(G4X_AUD_VID_DID);
        if (tmp == INTEL_AUDIO_DEVBLC || tmp == INTEL_AUDIO_DEVCL)
                eldv = G4X_ELDV_DEVCL_DEVBLC;
        else
                eldv = G4X_ELDV_DEVCTG;

        /* Invalidate ELD */
        tmp = I915_READ(G4X_AUD_CNTL_ST);
        tmp &= ~eldv;
        I915_WRITE(G4X_AUD_CNTL_ST, tmp);
}

static void g4x_audio_codec_enable(struct intel_encoder *encoder,
                                   const struct intel_crtc_state *crtc_state,
                                   const struct drm_connector_state *conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct drm_connector *connector = conn_state->connector;
        uint8_t *eld = connector->eld;
        uint32_t eldv;
        uint32_t tmp;
        int len, i;

        DRM_DEBUG_KMS("Enable audio codec, %u bytes ELD\n", eld[2]);

        tmp = I915_READ(G4X_AUD_VID_DID);
        if (tmp == INTEL_AUDIO_DEVBLC || tmp == INTEL_AUDIO_DEVCL)
                eldv = G4X_ELDV_DEVCL_DEVBLC;
        else
                eldv = G4X_ELDV_DEVCTG;

        if (intel_eld_uptodate(connector,
                               G4X_AUD_CNTL_ST, eldv,
                               G4X_AUD_CNTL_ST, G4X_ELD_ADDR_MASK,
                               G4X_HDMIW_HDMIEDID))
                return;

        tmp = I915_READ(G4X_AUD_CNTL_ST);
        tmp &= ~(eldv | G4X_ELD_ADDR_MASK);
        len = (tmp >> 9) & 0x1f;                /* ELD buffer size */
        I915_WRITE(G4X_AUD_CNTL_ST, tmp);

        len = min(drm_eld_size(eld) / 4, len);
        DRM_DEBUG_DRIVER("ELD size %d\n", len);
        for (i = 0; i < len; i++)
                I915_WRITE(G4X_HDMIW_HDMIEDID, *((uint32_t *)eld + i));

        tmp = I915_READ(G4X_AUD_CNTL_ST);
        tmp |= eldv;
        I915_WRITE(G4X_AUD_CNTL_ST, tmp);
}

static void
hsw_dp_audio_config_update(struct intel_encoder *encoder,
                           const struct intel_crtc_state *crtc_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct i915_audio_component *acomp = dev_priv->audio_component;
        struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
        enum port port = encoder->port;
        enum pipe pipe = crtc->pipe;
        const struct dp_aud_n_m *nm;
        int rate;
        u32 tmp;

        rate = acomp ? acomp->aud_sample_rate[port] : 0;
        nm = audio_config_dp_get_n_m(crtc_state, rate);
        if (nm)
                DRM_DEBUG_KMS("using Maud %u, Naud %u\n", nm->m, nm->n);
        else
                DRM_DEBUG_KMS("using automatic Maud, Naud\n");

        tmp = I915_READ(HSW_AUD_CFG(pipe));
        tmp &= ~AUD_CONFIG_N_VALUE_INDEX;
        tmp &= ~AUD_CONFIG_PIXEL_CLOCK_HDMI_MASK;
        tmp &= ~AUD_CONFIG_N_PROG_ENABLE;
        tmp |= AUD_CONFIG_N_VALUE_INDEX;

        if (nm) {
                tmp &= ~AUD_CONFIG_N_MASK;
                tmp |= AUD_CONFIG_N(nm->n);
                tmp |= AUD_CONFIG_N_PROG_ENABLE;
        }

        I915_WRITE(HSW_AUD_CFG(pipe), tmp);

        tmp = I915_READ(HSW_AUD_M_CTS_ENABLE(pipe));
        tmp &= ~AUD_CONFIG_M_MASK;
        tmp &= ~AUD_M_CTS_M_VALUE_INDEX;
        tmp &= ~AUD_M_CTS_M_PROG_ENABLE;

        if (nm) {
                tmp |= nm->m;
                tmp |= AUD_M_CTS_M_VALUE_INDEX;
                tmp |= AUD_M_CTS_M_PROG_ENABLE;
        }

        I915_WRITE(HSW_AUD_M_CTS_ENABLE(pipe), tmp);
}

static void
hsw_hdmi_audio_config_update(struct intel_encoder *encoder,
                             const struct intel_crtc_state *crtc_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct i915_audio_component *acomp = dev_priv->audio_component;
        struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
        enum port port = encoder->port;
        enum pipe pipe = crtc->pipe;
        int n, rate;
        u32 tmp;

        rate = acomp ? acomp->aud_sample_rate[port] : 0;

        tmp = I915_READ(HSW_AUD_CFG(pipe));
        tmp &= ~AUD_CONFIG_N_VALUE_INDEX;
        tmp &= ~AUD_CONFIG_PIXEL_CLOCK_HDMI_MASK;
        tmp &= ~AUD_CONFIG_N_PROG_ENABLE;
        tmp |= audio_config_hdmi_pixel_clock(crtc_state);

        n = audio_config_hdmi_get_n(crtc_state, rate);
        if (n != 0) {
                DRM_DEBUG_KMS("using N %d\n", n);

                tmp &= ~AUD_CONFIG_N_MASK;
                tmp |= AUD_CONFIG_N(n);
                tmp |= AUD_CONFIG_N_PROG_ENABLE;
        } else {
                DRM_DEBUG_KMS("using automatic N\n");
        }

        I915_WRITE(HSW_AUD_CFG(pipe), tmp);

        /*
         * Let's disable "Enable CTS or M Prog bit"
         * and let HW calculate the value
         */
        tmp = I915_READ(HSW_AUD_M_CTS_ENABLE(pipe));
        tmp &= ~AUD_M_CTS_M_PROG_ENABLE;
        tmp &= ~AUD_M_CTS_M_VALUE_INDEX;
        I915_WRITE(HSW_AUD_M_CTS_ENABLE(pipe), tmp);
}

static void
hsw_audio_config_update(struct intel_encoder *encoder,
                        const struct intel_crtc_state *crtc_state)
{
        if (intel_crtc_has_dp_encoder(crtc_state))
                hsw_dp_audio_config_update(encoder, crtc_state);
        else
                hsw_hdmi_audio_config_update(encoder, crtc_state);
}

static void hsw_audio_codec_disable(struct intel_encoder *encoder,
                                    const struct intel_crtc_state *old_crtc_state,
                                    const struct drm_connector_state *old_conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_crtc *crtc = to_intel_crtc(old_crtc_state->base.crtc);
        enum pipe pipe = crtc->pipe;
        uint32_t tmp;

        DRM_DEBUG_KMS("Disable audio codec on pipe %c\n", pipe_name(pipe));

        mutex_lock(&dev_priv->av_mutex);

        /* Disable timestamps */
        tmp = I915_READ(HSW_AUD_CFG(pipe));
        tmp &= ~AUD_CONFIG_N_VALUE_INDEX;
        tmp |= AUD_CONFIG_N_PROG_ENABLE;
        tmp &= ~AUD_CONFIG_UPPER_N_MASK;
        tmp &= ~AUD_CONFIG_LOWER_N_MASK;
        if (intel_crtc_has_dp_encoder(old_crtc_state))
                tmp |= AUD_CONFIG_N_VALUE_INDEX;
        I915_WRITE(HSW_AUD_CFG(pipe), tmp);

        /* Invalidate ELD */
        tmp = I915_READ(HSW_AUD_PIN_ELD_CP_VLD);
        tmp &= ~AUDIO_ELD_VALID(pipe);
        tmp &= ~AUDIO_OUTPUT_ENABLE(pipe);
        I915_WRITE(HSW_AUD_PIN_ELD_CP_VLD, tmp);

        mutex_unlock(&dev_priv->av_mutex);
}

static void hsw_audio_codec_enable(struct intel_encoder *encoder,
                                   const struct intel_crtc_state *crtc_state,
                                   const struct drm_connector_state *conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
        struct drm_connector *connector = conn_state->connector;
        enum pipe pipe = crtc->pipe;
        const uint8_t *eld = connector->eld;
        uint32_t tmp;
        int len, i;

        DRM_DEBUG_KMS("Enable audio codec on pipe %c, %u bytes ELD\n",
                      pipe_name(pipe), drm_eld_size(eld));

        mutex_lock(&dev_priv->av_mutex);

        /* Enable audio presence detect, invalidate ELD */
        tmp = I915_READ(HSW_AUD_PIN_ELD_CP_VLD);
        tmp |= AUDIO_OUTPUT_ENABLE(pipe);
        tmp &= ~AUDIO_ELD_VALID(pipe);
        I915_WRITE(HSW_AUD_PIN_ELD_CP_VLD, tmp);

        /*
         * FIXME: We're supposed to wait for vblank here, but we have vblanks
         * disabled during the mode set. The proper fix would be to push the
         * rest of the setup into a vblank work item, queued here, but the
         * infrastructure is not there yet.
         */

        /* Reset ELD write address */
        tmp = I915_READ(HSW_AUD_DIP_ELD_CTRL(pipe));
        tmp &= ~IBX_ELD_ADDRESS_MASK;
        I915_WRITE(HSW_AUD_DIP_ELD_CTRL(pipe), tmp);

        /* Up to 84 bytes of hw ELD buffer */
        len = min(drm_eld_size(eld), 84);
        for (i = 0; i < len / 4; i++)
                I915_WRITE(HSW_AUD_EDID_DATA(pipe), *((uint32_t *)eld + i));

        /* ELD valid */
        tmp = I915_READ(HSW_AUD_PIN_ELD_CP_VLD);
        tmp |= AUDIO_ELD_VALID(pipe);
        I915_WRITE(HSW_AUD_PIN_ELD_CP_VLD, tmp);

        /* Enable timestamps */
        hsw_audio_config_update(encoder, crtc_state);

        mutex_unlock(&dev_priv->av_mutex);
}

static void ilk_audio_codec_disable(struct intel_encoder *encoder,
                                    const struct intel_crtc_state *old_crtc_state,
                                    const struct drm_connector_state *old_conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_crtc *crtc = to_intel_crtc(old_crtc_state->base.crtc);
        enum pipe pipe = crtc->pipe;
        enum port port = encoder->port;
        uint32_t tmp, eldv;
        i915_reg_t aud_config, aud_cntrl_st2;

        DRM_DEBUG_KMS("Disable audio codec on port %c, pipe %c\n",
                      port_name(port), pipe_name(pipe));

        if (WARN_ON(port == PORT_A))
                return;

        if (HAS_PCH_IBX(dev_priv)) {
                aud_config = IBX_AUD_CFG(pipe);
                aud_cntrl_st2 = IBX_AUD_CNTL_ST2;
        } else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
                aud_config = VLV_AUD_CFG(pipe);
                aud_cntrl_st2 = VLV_AUD_CNTL_ST2;
        } else {
                aud_config = CPT_AUD_CFG(pipe);
                aud_cntrl_st2 = CPT_AUD_CNTRL_ST2;
        }

        /* Disable timestamps */
        tmp = I915_READ(aud_config);
        tmp &= ~AUD_CONFIG_N_VALUE_INDEX;
        tmp |= AUD_CONFIG_N_PROG_ENABLE;
        tmp &= ~AUD_CONFIG_UPPER_N_MASK;
        tmp &= ~AUD_CONFIG_LOWER_N_MASK;
        if (intel_crtc_has_dp_encoder(old_crtc_state))
                tmp |= AUD_CONFIG_N_VALUE_INDEX;
        I915_WRITE(aud_config, tmp);

        eldv = IBX_ELD_VALID(port);

        /* Invalidate ELD */
        tmp = I915_READ(aud_cntrl_st2);
        tmp &= ~eldv;
        I915_WRITE(aud_cntrl_st2, tmp);
}

static void ilk_audio_codec_enable(struct intel_encoder *encoder,
                                   const struct intel_crtc_state *crtc_state,
                                   const struct drm_connector_state *conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
        struct drm_connector *connector = conn_state->connector;
        enum pipe pipe = crtc->pipe;
        enum port port = encoder->port;
        uint8_t *eld = connector->eld;
        uint32_t tmp, eldv;
        int len, i;
        i915_reg_t hdmiw_hdmiedid, aud_config, aud_cntl_st, aud_cntrl_st2;

        DRM_DEBUG_KMS("Enable audio codec on port %c, pipe %c, %u bytes ELD\n",
                      port_name(port), pipe_name(pipe), drm_eld_size(eld));

        if (WARN_ON(port == PORT_A))
                return;

        /*
         * FIXME: We're supposed to wait for vblank here, but we have vblanks
         * disabled during the mode set. The proper fix would be to push the
         * rest of the setup into a vblank work item, queued here, but the
         * infrastructure is not there yet.
         */

        if (HAS_PCH_IBX(dev_priv)) {
                hdmiw_hdmiedid = IBX_HDMIW_HDMIEDID(pipe);
                aud_config = IBX_AUD_CFG(pipe);
                aud_cntl_st = IBX_AUD_CNTL_ST(pipe);
                aud_cntrl_st2 = IBX_AUD_CNTL_ST2;
        } else if (IS_VALLEYVIEW(dev_priv) ||
                   IS_CHERRYVIEW(dev_priv)) {
                hdmiw_hdmiedid = VLV_HDMIW_HDMIEDID(pipe);
                aud_config = VLV_AUD_CFG(pipe);
                aud_cntl_st = VLV_AUD_CNTL_ST(pipe);
                aud_cntrl_st2 = VLV_AUD_CNTL_ST2;
        } else {
                hdmiw_hdmiedid = CPT_HDMIW_HDMIEDID(pipe);
                aud_config = CPT_AUD_CFG(pipe);
                aud_cntl_st = CPT_AUD_CNTL_ST(pipe);
                aud_cntrl_st2 = CPT_AUD_CNTRL_ST2;
        }

        eldv = IBX_ELD_VALID(port);

        /* Invalidate ELD */
        tmp = I915_READ(aud_cntrl_st2);
        tmp &= ~eldv;
        I915_WRITE(aud_cntrl_st2, tmp);

        /* Reset ELD write address */
        tmp = I915_READ(aud_cntl_st);
        tmp &= ~IBX_ELD_ADDRESS_MASK;
        I915_WRITE(aud_cntl_st, tmp);

        /* Up to 84 bytes of hw ELD buffer */
        len = min(drm_eld_size(eld), 84);
        for (i = 0; i < len / 4; i++)
                I915_WRITE(hdmiw_hdmiedid, *((uint32_t *)eld + i));

        /* ELD valid */
        tmp = I915_READ(aud_cntrl_st2);
        tmp |= eldv;
        I915_WRITE(aud_cntrl_st2, tmp);

        /* Enable timestamps */
        tmp = I915_READ(aud_config);
        tmp &= ~AUD_CONFIG_N_VALUE_INDEX;
        tmp &= ~AUD_CONFIG_N_PROG_ENABLE;
        tmp &= ~AUD_CONFIG_PIXEL_CLOCK_HDMI_MASK;
        if (intel_crtc_has_dp_encoder(crtc_state))
                tmp |= AUD_CONFIG_N_VALUE_INDEX;
        else
                tmp |= audio_config_hdmi_pixel_clock(crtc_state);
        I915_WRITE(aud_config, tmp);
}

/**
 * intel_audio_codec_enable - Enable the audio codec for HD audio
 * @encoder: encoder on which to enable audio
 * @crtc_state: pointer to the current crtc state.
 * @conn_state: pointer to the current connector state.
 *
 * The enable sequences may only be performed after enabling the transcoder and
 * port, and after completed link training.
 */
void intel_audio_codec_enable(struct intel_encoder *encoder,
                              const struct intel_crtc_state *crtc_state,
                              const struct drm_connector_state *conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct i915_audio_component *acomp = dev_priv->audio_component;
        struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
        struct drm_connector *connector = conn_state->connector;
        const struct drm_display_mode *adjusted_mode =
                &crtc_state->base.adjusted_mode;
        enum port port = encoder->port;
        enum pipe pipe = crtc->pipe;

        if (!connector->eld[0])
                return;

        DRM_DEBUG_DRIVER("ELD on [CONNECTOR:%d:%s], [ENCODER:%d:%s]\n",
                         connector->base.id,
                         connector->name,
                         connector->encoder->base.id,
                         connector->encoder->name);

        connector->eld[6] = drm_av_sync_delay(connector, adjusted_mode) / 2;

        if (dev_priv->display.audio_codec_enable)
                dev_priv->display.audio_codec_enable(encoder,
                                                     crtc_state,
                                                     conn_state);

        mutex_lock(&dev_priv->av_mutex);
        encoder->audio_connector = connector;

        /* referred in audio callbacks */
        dev_priv->av_enc_map[pipe] = encoder;
        mutex_unlock(&dev_priv->av_mutex);

        if (acomp && acomp->audio_ops && acomp->audio_ops->pin_eld_notify) {
                /* audio drivers expect pipe = -1 to indicate Non-MST cases */
                if (!intel_crtc_has_type(crtc_state, INTEL_OUTPUT_DP_MST))
                        pipe = -1;
                acomp->audio_ops->pin_eld_notify(acomp->audio_ops->audio_ptr,
                                                 (int) port, (int) pipe);
        }

        intel_lpe_audio_notify(dev_priv, pipe, port, connector->eld,
                               crtc_state->port_clock,
                               intel_crtc_has_dp_encoder(crtc_state));
}

/**
 * intel_audio_codec_disable - Disable the audio codec for HD audio
 * @encoder: encoder on which to disable audio
 * @old_crtc_state: pointer to the old crtc state.
 * @old_conn_state: pointer to the old connector state.
 *
 * The disable sequences must be performed before disabling the transcoder or
 * port.
 */
void intel_audio_codec_disable(struct intel_encoder *encoder,
                               const struct intel_crtc_state *old_crtc_state,
                               const struct drm_connector_state *old_conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct i915_audio_component *acomp = dev_priv->audio_component;
        struct intel_crtc *crtc = to_intel_crtc(old_crtc_state->base.crtc);
        enum port port = encoder->port;
        enum pipe pipe = crtc->pipe;

        if (dev_priv->display.audio_codec_disable)
                dev_priv->display.audio_codec_disable(encoder,
                                                      old_crtc_state,
                                                      old_conn_state);

        mutex_lock(&dev_priv->av_mutex);
        encoder->audio_connector = NULL;
        dev_priv->av_enc_map[pipe] = NULL;
        mutex_unlock(&dev_priv->av_mutex);

        if (acomp && acomp->audio_ops && acomp->audio_ops->pin_eld_notify) {
                /* audio drivers expect pipe = -1 to indicate Non-MST cases */
                if (!intel_crtc_has_type(old_crtc_state, INTEL_OUTPUT_DP_MST))
                        pipe = -1;
                acomp->audio_ops->pin_eld_notify(acomp->audio_ops->audio_ptr,
                                                 (int) port, (int) pipe);
        }

        intel_lpe_audio_notify(dev_priv, pipe, port, NULL, 0, false);
}

/**
 * intel_init_audio_hooks - Set up chip specific audio hooks
 * @dev_priv: device private
 */
void intel_init_audio_hooks(struct drm_i915_private *dev_priv)
{
        if (IS_G4X(dev_priv)) {
                dev_priv->display.audio_codec_enable = g4x_audio_codec_enable;
                dev_priv->display.audio_codec_disable = g4x_audio_codec_disable;
        } else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
                dev_priv->display.audio_codec_enable = ilk_audio_codec_enable;
                dev_priv->display.audio_codec_disable = ilk_audio_codec_disable;
        } else if (IS_HASWELL(dev_priv) || INTEL_GEN(dev_priv) >= 8) {
                dev_priv->display.audio_codec_enable = hsw_audio_codec_enable;
                dev_priv->display.audio_codec_disable = hsw_audio_codec_disable;
        } else if (HAS_PCH_SPLIT(dev_priv)) {
                dev_priv->display.audio_codec_enable = ilk_audio_codec_enable;
                dev_priv->display.audio_codec_disable = ilk_audio_codec_disable;
        }
}

static void i915_audio_component_get_power(struct device *kdev)
{
        intel_display_power_get(kdev_to_i915(kdev), POWER_DOMAIN_AUDIO);
}

static void i915_audio_component_put_power(struct device *kdev)
{
        intel_display_power_put(kdev_to_i915(kdev), POWER_DOMAIN_AUDIO);
}

static void i915_audio_component_codec_wake_override(struct device *kdev,
                                                     bool enable)
{
        struct drm_i915_private *dev_priv = kdev_to_i915(kdev);
        u32 tmp;

        if (!IS_GEN9(dev_priv))
                return;

        i915_audio_component_get_power(kdev);

        /*
         * Enable/disable generating the codec wake signal, overriding the
         * internal logic to generate the codec wake to controller.
         */
        tmp = I915_READ(HSW_AUD_CHICKENBIT);
        tmp &= ~SKL_AUD_CODEC_WAKE_SIGNAL;
        I915_WRITE(HSW_AUD_CHICKENBIT, tmp);
        usleep_range(1000, 1500);

        if (enable) {
                tmp = I915_READ(HSW_AUD_CHICKENBIT);
                tmp |= SKL_AUD_CODEC_WAKE_SIGNAL;
                I915_WRITE(HSW_AUD_CHICKENBIT, tmp);
                usleep_range(1000, 1500);
        }

        i915_audio_component_put_power(kdev);
}

/* Get CDCLK in kHz  */
static int i915_audio_component_get_cdclk_freq(struct device *kdev)
{
        struct drm_i915_private *dev_priv = kdev_to_i915(kdev);

        if (WARN_ON_ONCE(!HAS_DDI(dev_priv)))
                return -ENODEV;

        return dev_priv->cdclk.hw.cdclk;
}

/*
 * get the intel_encoder according to the parameter port and pipe
 * intel_encoder is saved by the index of pipe
 * MST & (pipe >= 0): return the av_enc_map[pipe],
 *   when port is matched
 * MST & (pipe < 0): this is invalid
 * Non-MST & (pipe >= 0): only pipe = 0 (the first device entry)
 *   will get the right intel_encoder with port matched
 * Non-MST & (pipe < 0): get the right intel_encoder with port matched
 */
static struct intel_encoder *get_saved_enc(struct drm_i915_private *dev_priv,
                                               int port, int pipe)
{
        struct intel_encoder *encoder;

        /* MST */
        if (pipe >= 0) {
                if (WARN_ON(pipe >= ARRAY_SIZE(dev_priv->av_enc_map)))
                        return NULL;

                encoder = dev_priv->av_enc_map[pipe];
                /*
                 * when bootup, audio driver may not know it is
                 * MST or not. So it will poll all the port & pipe
                 * combinations
                 */
                if (encoder != NULL && encoder->port == port &&
                    encoder->type == INTEL_OUTPUT_DP_MST)
                        return encoder;
        }

        /* Non-MST */
        if (pipe > 0)
                return NULL;

        for_each_pipe(dev_priv, pipe) {
                encoder = dev_priv->av_enc_map[pipe];
                if (encoder == NULL)
                        continue;

                if (encoder->type == INTEL_OUTPUT_DP_MST)
                        continue;

                if (port == encoder->port)
                        return encoder;
        }

        return NULL;
}

static int i915_audio_component_sync_audio_rate(struct device *kdev, int port,
                                                int pipe, int rate)
{
        struct drm_i915_private *dev_priv = kdev_to_i915(kdev);
        struct i915_audio_component *acomp = dev_priv->audio_component;
        struct intel_encoder *encoder;
        struct intel_crtc *crtc;
        int err = 0;

        if (!HAS_DDI(dev_priv))
                return 0;

        i915_audio_component_get_power(kdev);
        mutex_lock(&dev_priv->av_mutex);

        /* 1. get the pipe */
        encoder = get_saved_enc(dev_priv, port, pipe);
        if (!encoder || !encoder->base.crtc) {
                DRM_DEBUG_KMS("Not valid for port %c\n", port_name(port));
                err = -ENODEV;
                goto unlock;
        }

        crtc = to_intel_crtc(encoder->base.crtc);

        /* port must be valid now, otherwise the pipe will be invalid */
        acomp->aud_sample_rate[port] = rate;

        hsw_audio_config_update(encoder, crtc->config);

 unlock:
        mutex_unlock(&dev_priv->av_mutex);
        i915_audio_component_put_power(kdev);
        return err;
}

static int i915_audio_component_get_eld(struct device *kdev, int port,
                                        int pipe, bool *enabled,
                                        unsigned char *buf, int max_bytes)
{
        struct drm_i915_private *dev_priv = kdev_to_i915(kdev);
        struct intel_encoder *intel_encoder;
        const u8 *eld;
        int ret = -EINVAL;

        mutex_lock(&dev_priv->av_mutex);

        intel_encoder = get_saved_enc(dev_priv, port, pipe);
        if (!intel_encoder) {
                DRM_DEBUG_KMS("Not valid for port %c\n", port_name(port));
                mutex_unlock(&dev_priv->av_mutex);
                return ret;
        }

        ret = 0;
        *enabled = intel_encoder->audio_connector != NULL;
        if (*enabled) {
                eld = intel_encoder->audio_connector->eld;
                ret = drm_eld_size(eld);
                memcpy(buf, eld, min(max_bytes, ret));
        }

        mutex_unlock(&dev_priv->av_mutex);
        return ret;
}

static const struct i915_audio_component_ops i915_audio_component_ops = {
        .owner          = THIS_MODULE,
        .get_power      = i915_audio_component_get_power,
        .put_power      = i915_audio_component_put_power,
        .codec_wake_override = i915_audio_component_codec_wake_override,
        .get_cdclk_freq = i915_audio_component_get_cdclk_freq,
        .sync_audio_rate = i915_audio_component_sync_audio_rate,
        .get_eld        = i915_audio_component_get_eld,
};

static int i915_audio_component_bind(struct device *i915_kdev,
                                     struct device *hda_kdev, void *data)
{
        struct i915_audio_component *acomp = data;
        struct drm_i915_private *dev_priv = kdev_to_i915(i915_kdev);
        int i;

        if (WARN_ON(acomp->ops || acomp->dev))
                return -EEXIST;

        drm_modeset_lock_all(&dev_priv->drm);
        acomp->ops = &i915_audio_component_ops;
        acomp->dev = i915_kdev;
        BUILD_BUG_ON(MAX_PORTS != I915_MAX_PORTS);
        for (i = 0; i < ARRAY_SIZE(acomp->aud_sample_rate); i++)
                acomp->aud_sample_rate[i] = 0;
        dev_priv->audio_component = acomp;
        drm_modeset_unlock_all(&dev_priv->drm);

        return 0;
}

static void i915_audio_component_unbind(struct device *i915_kdev,
                                        struct device *hda_kdev, void *data)
{
        struct i915_audio_component *acomp = data;
        struct drm_i915_private *dev_priv = kdev_to_i915(i915_kdev);

        drm_modeset_lock_all(&dev_priv->drm);
        acomp->ops = NULL;
        acomp->dev = NULL;
        dev_priv->audio_component = NULL;
        drm_modeset_unlock_all(&dev_priv->drm);
}

static const struct component_ops i915_audio_component_bind_ops = {
        .bind   = i915_audio_component_bind,
        .unbind = i915_audio_component_unbind,
};

/**
 * i915_audio_component_init - initialize and register the audio component
 * @dev_priv: i915 device instance
 *
 * This will register with the component framework a child component which
 * will bind dynamically to the snd_hda_intel driver's corresponding master
 * component when the latter is registered. During binding the child
 * initializes an instance of struct i915_audio_component which it receives
 * from the master. The master can then start to use the interface defined by
 * this struct. Each side can break the binding at any point by deregistering
 * its own component after which each side's component unbind callback is
 * called.
 *
 * We ignore any error during registration and continue with reduced
 * functionality (i.e. without HDMI audio).
 */
void i915_audio_component_init(struct drm_i915_private *dev_priv)
{
        int ret;

        if (INTEL_INFO(dev_priv)->num_pipes == 0)
                return;

        ret = component_add(dev_priv->drm.dev, &i915_audio_component_bind_ops);
        if (ret < 0) {
                DRM_ERROR("failed to add audio component (%d)\n", ret);
                /* continue with reduced functionality */
                return;
        }

        dev_priv->audio_component_registered = true;
}

/**
 * i915_audio_component_cleanup - deregister the audio component
 * @dev_priv: i915 device instance
 *
 * Deregisters the audio component, breaking any existing binding to the
 * corresponding snd_hda_intel driver's master component.
 */
void i915_audio_component_cleanup(struct drm_i915_private *dev_priv)
{
        if (!dev_priv->audio_component_registered)
                return;

        component_del(dev_priv->drm.dev, &i915_audio_component_bind_ops);
        dev_priv->audio_component_registered = false;
}

/**
 * intel_audio_init() - Initialize the audio driver either using
 * component framework or using lpe audio bridge
 * @dev_priv: the i915 drm device private data
 *
 */
void intel_audio_init(struct drm_i915_private *dev_priv)
{
        if (intel_lpe_audio_init(dev_priv) < 0)
                i915_audio_component_init(dev_priv);
}

/**
 * intel_audio_deinit() - deinitialize the audio driver
 * @dev_priv: the i915 drm device private data
 *
 */
void intel_audio_deinit(struct drm_i915_private *dev_priv)
{

        if ((dev_priv)->lpe_audio.platdev != NULL)
                intel_lpe_audio_teardown(dev_priv);
        else
                i915_audio_component_cleanup(dev_priv);
}