CloverBootloader/Drivers/AudioDxe/HdaCodec/HdaCodec.c

/*
 * File: HdaCodec.c
 *
 * Copyright (c) 2018 John Davis
 *
 * 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 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 "HdaCodec.h"
#include "HdaCodecComponentName.h"
//#include <IndustryStandard/HdaCodec.h>
#include <Library/HdaModels.h>

EFI_STATUS
EFIAPI
HdaCodecProbeWidget(
    IN HDA_WIDGET_DEV *HdaWidget)
{
    //DEBUG((DEBUG_INFO, "HdaCodecProbeWidget(): start\n"));

    // Create variables.
    EFI_STATUS Status;
    EFI_HDA_IO_PROTOCOL *HdaIo = HdaWidget->FuncGroup->HdaCodecDev->HdaIo;
    UINT32 Response = 0;
    UINT8 ConnectionListThresh;
    UINT8 AmpInCount;

    // Get widget capabilities.
    Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_WIDGET_CAPS), &HdaWidget->Capabilities);
    if (EFI_ERROR(Status))
        return Status;
    HdaWidget->Type = HDA_PARAMETER_WIDGET_CAPS_TYPE(HdaWidget->Capabilities);
    HdaWidget->AmpOverride = HdaWidget->Capabilities & HDA_PARAMETER_WIDGET_CAPS_AMP_OVERRIDE;
    //DEBUG((DEBUG_INFO, "Widget @ 0x%X type: 0x%X\n", HdaWidget->NodeId, HdaWidget->Type));
    //DEBUG((DEBUG_INFO, "Widget @ 0x%X capabilities: 0x%X\n", HdaWidget->NodeId, HdaWidget->Capabilities));

    // Get default unsolicitation.
    if (HdaWidget->Capabilities & HDA_PARAMETER_WIDGET_CAPS_UNSOL_CAPABLE) {
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_UNSOL_RESPONSE, 0), &Response);
        if (EFI_ERROR(Status))
            return Status;
        HdaWidget->DefaultUnSol = (UINT8)Response;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X unsolicitation: 0x%X\n", HdaWidget->NodeId, HdaWidget->DefaultUnSol));
    }

    // Get connections.
    if (HdaWidget->Capabilities & HDA_PARAMETER_WIDGET_CAPS_CONN_LIST) {
        // Get connection list length.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_CONN_LIST_LENGTH), &HdaWidget->ConnectionListLength);
        if (EFI_ERROR(Status))
            return Status;
        HdaWidget->ConnectionCount = HDA_PARAMETER_CONN_LIST_LENGTH_LEN(HdaWidget->ConnectionListLength);
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X connection list length: 0x%X\n", HdaWidget->NodeId, HdaWidget->ConnectionListLength));

        // Get connections.
        HdaWidget->Connections = AllocateZeroPool(sizeof(UINT16) * HdaWidget->ConnectionCount);
        if (HdaWidget->Connections == NULL)
            return EFI_OUT_OF_RESOURCES;
        ConnectionListThresh = (HdaWidget->ConnectionListLength & HDA_PARAMETER_CONN_LIST_LENGTH_LONG) ? 2 : 4;
        for (UINT8 c = 0; c < HdaWidget->ConnectionCount; c++) {
            // Do we need to get entries?
            if (!(c % ConnectionListThresh)) {
                // Get connection entries.
                Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
                    HDA_CODEC_VERB(HDA_VERB_GET_CONN_LIST_ENTRY, c), &Response);
                if (EFI_ERROR(Status))
                    return Status;
            }

            // Populate entry list.
            if ((HdaWidget->ConnectionListLength & HDA_PARAMETER_CONN_LIST_LENGTH_LONG))
                HdaWidget->Connections[c] = HDA_VERB_GET_CONN_LIST_ENTRY_LONG(Response, c % 2);
            else
                HdaWidget->Connections[c] = HDA_VERB_GET_CONN_LIST_ENTRY_SHORT(Response, c % 4);
        }
    }

    // Print connections.
    //DEBUG((DEBUG_INFO, "Widget @ 0x%X connections (%u):", HdaWidget->NodeId, HdaWidget->ConnectionCount));
    //for (UINT8 c = 0; c < HdaWidget->ConnectionCount; c++)
        //DEBUG((DEBUG_INFO, " 0x%X", HdaWidget->Connections[c]));
    //DEBUG((DEBUG_INFO, "\n"));

    // Does the widget support power management?
    if (HdaWidget->Capabilities & HDA_PARAMETER_WIDGET_CAPS_POWER_CNTRL) {
        // Get supported power states.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_SUPPORTED_POWER_STATES), &HdaWidget->SupportedPowerStates);
        if (EFI_ERROR(Status))
            return Status;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X supported power states: 0x%X\n", HdaWidget->NodeId, HdaWidget->SupportedPowerStates));

        // Get default power state.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_POWER_STATE, 0), &HdaWidget->DefaultPowerState);
        if (EFI_ERROR(Status))
            return Status;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X power state: 0x%X\n", HdaWidget->NodeId, HdaWidget->DefaultPowerState));
    }

    // Do we have input amps?
    if (HdaWidget->Capabilities & HDA_PARAMETER_WIDGET_CAPS_IN_AMP) {
        // Get input amp capabilities.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_AMP_CAPS_INPUT), &HdaWidget->AmpInCapabilities);
        if (EFI_ERROR(Status))
            return Status;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X input amp capabilities: 0x%X\n", HdaWidget->NodeId, HdaWidget->AmpInCapabilities));

        // Determine number of input amps and allocate arrays.
        AmpInCount = HdaWidget->ConnectionCount;
        if (AmpInCount < 1)
            AmpInCount = 1;
        HdaWidget->AmpInLeftDefaultGainMute = AllocateZeroPool(sizeof(UINT8) * AmpInCount);
        HdaWidget->AmpInRightDefaultGainMute = AllocateZeroPool(sizeof(UINT8) * AmpInCount);
        if ((HdaWidget->AmpInLeftDefaultGainMute == NULL) || (HdaWidget->AmpInRightDefaultGainMute == NULL))
            return EFI_OUT_OF_RESOURCES;

        // Get default gain/mute for input amps.
        for (UINT8 i = 0; i < AmpInCount; i++) {
            // Get left.
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_AMP_GAIN_MUTE,
            HDA_VERB_GET_AMP_GAIN_MUTE_PAYLOAD(i, TRUE, FALSE)), &Response);
            if (EFI_ERROR(Status))
                return Status;
            HdaWidget->AmpInLeftDefaultGainMute[i] = (UINT8)Response;

            // Get right.
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_AMP_GAIN_MUTE,
            HDA_VERB_GET_AMP_GAIN_MUTE_PAYLOAD(i, FALSE, FALSE)), &Response);
            if (EFI_ERROR(Status))
                return Status;
            HdaWidget->AmpInRightDefaultGainMute[i] = (UINT8)Response;
            //DEBUG((DEBUG_INFO, "Widget @ 0x%X input amp %u defaults: 0x%X 0x%X\n", HdaWidget->NodeId, i,
            //    HdaWidget->AmpInLeftDefaultGainMute[i], HdaWidget->AmpInRightDefaultGainMute[i]));
        }
    }

    // Do we have an output amp?
    if (HdaWidget->Capabilities & HDA_PARAMETER_WIDGET_CAPS_OUT_AMP) {
        // Get output amp capabilities.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_AMP_CAPS_OUTPUT), &HdaWidget->AmpOutCapabilities);
        if (EFI_ERROR(Status))
            return Status;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X output amp capabilities: 0x%X\n", HdaWidget->NodeId, HdaWidget->AmpOutCapabilities));

        // Get left.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
        HDA_CODEC_VERB(HDA_VERB_GET_AMP_GAIN_MUTE,
        HDA_VERB_GET_AMP_GAIN_MUTE_PAYLOAD(0, TRUE, TRUE)), &Response);
        if (EFI_ERROR(Status))
            return Status;
        HdaWidget->AmpOutLeftDefaultGainMute = (UINT8)Response;

        // Get right.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
        HDA_CODEC_VERB(HDA_VERB_GET_AMP_GAIN_MUTE,
        HDA_VERB_GET_AMP_GAIN_MUTE_PAYLOAD(0, FALSE, TRUE)), &Response);
        if (EFI_ERROR(Status))
            return Status;
        HdaWidget->AmpOutRightDefaultGainMute = (UINT8)Response;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X output amp defaults: 0x%X 0x%X\n", HdaWidget->NodeId,
        //    HdaWidget->AmpOutLeftDefaultGainMute, HdaWidget->AmpOutRightDefaultGainMute));
    }

    // Is the widget an Input or Output?
    if (HdaWidget->Type == HDA_WIDGET_TYPE_INPUT || HdaWidget->Type == HDA_WIDGET_TYPE_OUTPUT) {
        if (HdaWidget->Capabilities & HDA_PARAMETER_WIDGET_CAPS_FORMAT_OVERRIDE) {
            // Get supported PCM sizes/rates.
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
                HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_SUPPORTED_PCM_SIZE_RATES), &HdaWidget->SupportedPcmRates);
            if (EFI_ERROR(Status))
                return Status;
            //DEBUG((DEBUG_INFO, "Widget @ 0x%X supported PCM sizes/rates: 0x%X\n", HdaWidget->NodeId, HdaWidget->SupportedPcmRates));

            // Get supported stream formats.
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
                HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_SUPPORTED_STREAM_FORMATS), &HdaWidget->SupportedFormats);
            if (EFI_ERROR(Status))
                return Status;
            //DEBUG((DEBUG_INFO, "Widget @ 0x%X supported formats: 0x%X\n", HdaWidget->NodeId, HdaWidget->SupportedFormats));
        }

        // Get default converter format.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_CONVERTER_FORMAT, 0), &Response);
        if (EFI_ERROR(Status))
            return Status;
        HdaWidget->DefaultConvFormat = (UINT16)Response;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X default format: 0x%X\n", HdaWidget->NodeId, HdaWidget->DefaultConvFormat));

        // Get default converter stream/channel.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_CONVERTER_STREAM_CHANNEL, 0), &Response);
        if (EFI_ERROR(Status))
            return Status;
        HdaWidget->DefaultConvStreamChannel = (UINT8)Response;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X default stream/channel: 0x%X\n", HdaWidget->NodeId, HdaWidget->DefaultConvStreamChannel));

        // Get default converter channel count.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_CONVERTER_CHANNEL_COUNT, 0), &Response);
        if (EFI_ERROR(Status))
            return Status;
        HdaWidget->DefaultConvChannelCount = (UINT8)Response;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X default channel count: 0x%X\n", HdaWidget->NodeId, HdaWidget->DefaultConvChannelCount));
    } else if (HdaWidget->Type == HDA_WIDGET_TYPE_PIN_COMPLEX) { // Is the widget a Pin Complex?
        // Get pin capabilities.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_PIN_CAPS), &HdaWidget->PinCapabilities);
        if (EFI_ERROR(Status))
            return Status;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X pin capabilities: 0x%X\n", HdaWidget->NodeId, HdaWidget->PinCapabilities));

        // Get default EAPD.
        if (HdaWidget->PinCapabilities & HDA_PARAMETER_PIN_CAPS_EAPD) {
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
                HDA_CODEC_VERB(HDA_VERB_GET_EAPD_BTL_ENABLE, 0), &Response);
            if (EFI_ERROR(Status))
                return Status;
            HdaWidget->DefaultEapd = (UINT8)Response;
            HdaWidget->DefaultEapd &= 0x7;
            HdaWidget->DefaultEapd |= HDA_EAPD_BTL_ENABLE_EAPD;
            //DEBUG((DEBUG_INFO, "Widget @ 0x%X EAPD: 0x%X\n", HdaWidget->NodeId, HdaWidget->DefaultEapd));
        }

        // Get default pin control.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_PIN_WIDGET_CONTROL, 0), &Response);
        if (EFI_ERROR(Status))
            return Status;
        HdaWidget->DefaultPinControl = (UINT8)Response;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X default pin control: 0x%X\n", HdaWidget->NodeId, HdaWidget->DefaultPinControl));

        // Get default pin configuration.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_CONFIGURATION_DEFAULT, 0), &HdaWidget->DefaultConfiguration);
        if (EFI_ERROR(Status))
            return Status;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X default pin configuration: 0x%X\n", HdaWidget->NodeId, HdaWidget->DefaultConfiguration));
    } else if (HdaWidget->Type == HDA_WIDGET_TYPE_VOLUME_KNOB) { // Is the widget a Volume Knob?
        // Get volume knob capabilities.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_VOLUME_KNOB_CAPS), &HdaWidget->VolumeCapabilities);
        if (EFI_ERROR(Status))
            return Status;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X volume knob capabilities: 0x%X\n", HdaWidget->NodeId, HdaWidget->VolumeCapabilities));

        // Get default volume.
        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId,
            HDA_CODEC_VERB(HDA_VERB_GET_VOLUME_KNOB, 0), &Response);
        if (EFI_ERROR(Status))
            return Status;
        HdaWidget->DefaultVolume = (UINT8)Response;
        //DEBUG((DEBUG_INFO, "Widget @ 0x%X default volume: 0x%X\n", HdaWidget->NodeId, HdaWidget->DefaultVolume));
    }

    return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
HdaCodecProbeFuncGroup(
    IN HDA_FUNC_GROUP *FuncGroup) {
    //DEBUG((DEBUG_INFO, "HdaCodecProbeFuncGroup(): start\n"));

    // Create variables.
    EFI_STATUS Status;
    EFI_HDA_IO_PROTOCOL *HdaIo = FuncGroup->HdaCodecDev->HdaIo;
    UINT32 Response;

    UINT8 WidgetStart;
    UINT8 WidgetEnd;
    UINT8 WidgetCount;
    HDA_WIDGET_DEV *HdaWidget;
    HDA_WIDGET_DEV *HdaConnectedWidget;

    // Get function group type.
    Status = HdaIo->SendCommand(HdaIo, FuncGroup->NodeId,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_FUNC_GROUP_TYPE), &Response);
    if (EFI_ERROR(Status))
        return Status;
    FuncGroup->Type = HDA_PARAMETER_FUNC_GROUP_TYPE_NODETYPE(Response);
    FuncGroup->UnsolCapable = (Response & HDA_PARAMETER_FUNC_GROUP_TYPE_UNSOL) != 0;

    // Determine if function group is an audio one. If not, we cannot support it.
    DEBUG((DEBUG_INFO, "Function group @ 0x%X is of type 0x%X\n", FuncGroup->NodeId, FuncGroup->Type));
    if (FuncGroup->Type != HDA_FUNC_GROUP_TYPE_AUDIO)
        return EFI_UNSUPPORTED;

    // Get function group capabilities.
    Status = HdaIo->SendCommand(HdaIo, FuncGroup->NodeId,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_FUNC_GROUP_CAPS), &FuncGroup->Capabilities);
    if (EFI_ERROR(Status))
        return Status;
    //DEBUG((DEBUG_INFO, "Function group @ 0x%X capabilities: 0x%X\n", FuncGroup->NodeId, FuncGroup->Capabilities));

    // Get default supported PCM sizes/rates.
    Status = HdaIo->SendCommand(HdaIo, FuncGroup->NodeId,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_SUPPORTED_PCM_SIZE_RATES), &FuncGroup->SupportedPcmRates);
    if (EFI_ERROR(Status))
        return Status;
    //DEBUG((DEBUG_INFO, "Function group @ 0x%X supported PCM sizes/rates: 0x%X\n", FuncGroup->NodeId, FuncGroup->SupportedPcmRates));

    // Get default supported stream formats.
    Status = HdaIo->SendCommand(HdaIo, FuncGroup->NodeId,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_SUPPORTED_STREAM_FORMATS), &FuncGroup->SupportedFormats);
    if (EFI_ERROR(Status))
        return Status;
    //DEBUG((DEBUG_INFO, "Function group @ 0x%X supported formats: 0x%X\n", FuncGroup->NodeId, FuncGroup->SupportedFormats));

    // Get default input amp capabilities.
    Status = HdaIo->SendCommand(HdaIo, FuncGroup->NodeId,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_AMP_CAPS_INPUT), &FuncGroup->AmpInCapabilities);
    if (EFI_ERROR(Status))
        return Status;
    //DEBUG((DEBUG_INFO, "Function group @ 0x%X input amp capabilities: 0x%X\n", FuncGroup->NodeId, FuncGroup->AmpInCapabilities));

    // Get default output amp capabilities.
    Status = HdaIo->SendCommand(HdaIo, FuncGroup->NodeId,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_AMP_CAPS_OUTPUT), &FuncGroup->AmpOutCapabilities);
    if (EFI_ERROR(Status))
        return Status;
    //DEBUG((DEBUG_INFO, "Function group @ 0x%X output amp capabilities: 0x%X\n", FuncGroup->NodeId, FuncGroup->AmpOutCapabilities));

    // Get supported power states.
    Status = HdaIo->SendCommand(HdaIo, FuncGroup->NodeId,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_SUPPORTED_POWER_STATES), &FuncGroup->SupportedPowerStates);
    if (EFI_ERROR(Status))
        return Status;
    //DEBUG((DEBUG_INFO, "Function group @ 0x%X supported power states: 0x%X\n", FuncGroup->NodeId, FuncGroup->SupportedPowerStates));

    // Get GPIO capabilities.
    Status = HdaIo->SendCommand(HdaIo, FuncGroup->NodeId,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_GPIO_COUNT), &FuncGroup->GpioCapabilities);
    if (EFI_ERROR(Status))
        return Status;
    //DEBUG((DEBUG_INFO, "Function group @ 0x%X GPIO capabilities: 0x%X\n", FuncGroup->NodeId, FuncGroup->GpioCapabilities));

    // Get number of widgets in function group.
    Status = HdaIo->SendCommand(HdaIo, FuncGroup->NodeId,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_SUBNODE_COUNT), &Response);
    if (EFI_ERROR(Status))
        return Status;
    WidgetStart = HDA_PARAMETER_SUBNODE_COUNT_START(Response);
    WidgetCount = HDA_PARAMETER_SUBNODE_COUNT_TOTAL(Response);
    WidgetEnd = WidgetStart + WidgetCount - 1;
    DEBUG((DEBUG_INFO, "Function group @ 0x%X contains %u widgets, start @ 0x%X, end @ 0x%X\n",
        FuncGroup->NodeId, WidgetCount, WidgetStart, WidgetEnd));

    // Power up.
    Status = HdaIo->SendCommand(HdaIo, FuncGroup->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_POWER_STATE, 0), &Response);
    ASSERT_EFI_ERROR(Status);

    // Ensure there are widgets.
    if (WidgetCount == 0)
        return EFI_UNSUPPORTED;

    // Allocate space for widgets.
    FuncGroup->Widgets = AllocateZeroPool(sizeof(HDA_WIDGET_DEV) * WidgetCount);
    if (FuncGroup->Widgets == NULL)
        return EFI_OUT_OF_RESOURCES;
    FuncGroup->WidgetsCount = WidgetCount;

    // Probe widgets.
    DEBUG((DEBUG_INFO, "HdaCodecProbeFuncGroup(): probing widgets\n"));
    for (UINT8 w = 0; w < WidgetCount; w++) {
        // Get widget.
        HdaWidget = FuncGroup->Widgets + w;

        // Probe widget.
        HdaWidget->FuncGroup = FuncGroup;
        HdaWidget->NodeId = WidgetStart + w;
        Status = HdaCodecProbeWidget(HdaWidget);
        ASSERT_EFI_ERROR(Status);

        // Power up.
        if (HdaWidget->Capabilities & HDA_PARAMETER_WIDGET_CAPS_POWER_CNTRL) {
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_POWER_STATE, 0), &Response);
            ASSERT_EFI_ERROR(Status);
        }
    }

    // Probe widget connections.
    DEBUG((DEBUG_INFO, "HdaCodecProbeFuncGroup(): probing widget connections\n"));
    for (UINT8 w = 0; w < WidgetCount; w++) {
        // Get widget.
        HdaWidget = FuncGroup->Widgets + w;

        // Get connections.
        if (HdaWidget->ConnectionCount > 0) {
            // Allocate array of widget pointers.
            HdaWidget->WidgetConnections = AllocateZeroPool(sizeof(HDA_WIDGET_DEV*) * HdaWidget->ConnectionCount);
            if (HdaWidget->WidgetConnections == NULL)
                return EFI_OUT_OF_RESOURCES;

            // Populate array.
            for (UINT8 c = 0; c < HdaWidget->ConnectionCount; c++) {
                // Get widget index.
                // This can be gotten using the node ID of the connection minus our starting node ID.
                UINT16 WidgetIndex = HdaWidget->Connections[c] - WidgetStart;
                if (WidgetIndex < 0) {
                    DEBUG((DEBUG_INFO, "Widget @ 0x%X error connection to index %u (0x%X) is invalid\n", WidgetIndex, HdaWidget->Connections[c]));
                    continue;
                }

                // Save pointer to widget.
                HdaConnectedWidget = FuncGroup->Widgets + WidgetIndex;
                //DEBUG((DEBUG_INFO, "Widget @ 0x%X found connection to index %u (0x%X, type 0x%X)\n",
                //    HdaWidget->NodeId, WidgetIndex, HdaConnectedWidget->NodeId, HdaConnectedWidget->Type));
                HdaWidget->WidgetConnections[c] = HdaConnectedWidget;
            }
        }
    }

    return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
HdaCodecProbeCodec(
    IN HDA_CODEC_DEV *HdaCodecDev)
{
    //DEBUG((DEBUG_INFO, "HdaCodecProbeCodec(): start\n"));

    // Create variables.
    EFI_STATUS Status;
    EFI_HDA_IO_PROTOCOL *HdaIo = HdaCodecDev->HdaIo;
    UINT32 Response;
    UINT8 FuncStart;
    UINT8 FuncEnd;
    UINT8 FuncCount;

    // Get vendor and device ID.
    Status = HdaIo->SendCommand(HdaIo, HDA_NID_ROOT,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_VENDOR_ID), &HdaCodecDev->VendorId);
    if (EFI_ERROR(Status))
        return Status;
    DEBUG((DEBUG_INFO, "Codec ID: 0x%X:0x%X\n", HDA_PARAMETER_VENDOR_ID_VEN(HdaCodecDev->VendorId), HDA_PARAMETER_VENDOR_ID_DEV(HdaCodecDev->VendorId)));

    // Get revision ID.
    Status = HdaIo->SendCommand(HdaIo, HDA_NID_ROOT,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_REVISION_ID), &HdaCodecDev->RevisionId);
    if (EFI_ERROR(Status))
        return Status;

    HdaCodecGetName(HdaCodecDev->VendorId, (UINT16)HdaCodecDev->RevisionId, &HdaCodecDev->Name);

    // Get function group count.
    Status = HdaIo->SendCommand(HdaIo, HDA_NID_ROOT,
        HDA_CODEC_VERB(HDA_VERB_GET_PARAMETER, HDA_PARAMETER_SUBNODE_COUNT), &Response);
    if (EFI_ERROR(Status))
        return Status;
    FuncStart = HDA_PARAMETER_SUBNODE_COUNT_START(Response);
    FuncCount = HDA_PARAMETER_SUBNODE_COUNT_TOTAL(Response);
    FuncEnd = FuncStart + FuncCount - 1;
    DEBUG((DEBUG_INFO, "Codec contains %u function groups, start @ 0x%X, end @ 0x%X\n", FuncCount, FuncStart, FuncEnd));

    // Ensure there are functions.
    if (FuncCount == 0)
        return EFI_UNSUPPORTED;

    // Allocate space for function groups.
    HdaCodecDev->FuncGroups = AllocateZeroPool(sizeof(HDA_FUNC_GROUP) * FuncCount);
    if (HdaCodecDev->FuncGroups == NULL)
        return EFI_OUT_OF_RESOURCES;
    HdaCodecDev->FuncGroupsCount = FuncCount;
    HdaCodecDev->AudioFuncGroup = NULL;

    // Probe functions.
    for (UINT8 i = 0; i < FuncCount; i++) {
        HdaCodecDev->FuncGroups[i].HdaCodecDev = HdaCodecDev;
        HdaCodecDev->FuncGroups[i].NodeId = FuncStart + i;
        Status = HdaCodecProbeFuncGroup(HdaCodecDev->FuncGroups + i);
        if (!(EFI_ERROR(Status)) && (HdaCodecDev->AudioFuncGroup == NULL))
            HdaCodecDev->AudioFuncGroup = HdaCodecDev->FuncGroups + i;
    }

    return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
HdaCodecFindUpstreamOutput(
    IN HDA_WIDGET_DEV *HdaWidget,
    IN UINT8 Level)
{
    EFI_STATUS Status;
    HDA_WIDGET_DEV *HdaConnectedWidget;

    //DEBUG((DEBUG_INFO, "HdaCodecFindUpstreamOutput(): start\n"));

    // If level is above 15, we may have entered an infinite loop so just give up.
    if (Level > 15) {
        return EFI_ABORTED;
    }

    // Go through connections and check for Output widgets.
    for (UINT8 c = 0; c < HdaWidget->ConnectionCount; c++) {
        // Get connected widget.
        HdaConnectedWidget = HdaWidget->WidgetConnections[c];
        for (UINT8 i = 0; i <= Level; i++) {
            DEBUG((DEBUG_INFO, "  "));
        }
        DEBUG((DEBUG_INFO, "Widget @ 0x%X (type 0x%X)\n", HdaConnectedWidget->NodeId, HdaConnectedWidget->Type));

        // If this is an Output, we are done.
        if (HdaConnectedWidget->Type == HDA_WIDGET_TYPE_OUTPUT) {
            HdaWidget->UpstreamWidget = HdaConnectedWidget;
            HdaWidget->UpstreamIndex = c;
            return EFI_SUCCESS;
        }

        // Check connections of connected widget.
        // If a success status is returned, that means an Output widget was found and we are done.
        Status = HdaCodecFindUpstreamOutput(HdaConnectedWidget, Level + 1);
        if (Status == EFI_SUCCESS) {
            HdaWidget->UpstreamWidget = HdaConnectedWidget;
            HdaWidget->UpstreamIndex = c;
            return EFI_SUCCESS;
        }
    }

    // We didn't find an Output if we got here (probably zero connections).
    return EFI_NOT_FOUND;
}

EFI_STATUS
EFIAPI
HdaCodecParsePorts(
    IN HDA_CODEC_DEV *HdaCodecDev) {
    //DEBUG((DEBUG_INFO, "HdaCodecParsePorts(): start\n"));

    // Create variables.
    EFI_STATUS Status;
    EFI_HDA_IO_PROTOCOL *HdaIo = HdaCodecDev->HdaIo;
    HDA_FUNC_GROUP *HdaFuncGroup;
    HDA_WIDGET_DEV *HdaWidget;
    UINT8 DefaultDeviceType;
    UINT32 Response;

    // Loop through each function group.
    for (UINT8 f = 0; f < HdaCodecDev->FuncGroupsCount; f++) {
        // Get function group.
        HdaFuncGroup = HdaCodecDev->FuncGroups + f;

        // Loop through each widget.
        for (UINT8 w = 0; w < HdaFuncGroup->WidgetsCount; w++) {
            // Get widget.
            HdaWidget = HdaFuncGroup->Widgets + w;

            // Is the widget a pin complex? If not, ignore it.
            // If this is a pin complex but it has no connection to a port, also ignore it.
            // If the default association for the pin complex is zero, also ignore it.
            if ((HdaWidget->Type != HDA_WIDGET_TYPE_PIN_COMPLEX) ||
                (HDA_VERB_GET_CONFIGURATION_DEFAULT_PORT_CONN(HdaWidget->DefaultConfiguration) == HDA_CONFIG_DEFAULT_PORT_CONN_NONE) ||
                (HDA_VERB_GET_CONFIGURATION_DEFAULT_ASSOCIATION(HdaWidget->DefaultConfiguration) == 0))
                continue;

            // Determine if port is an output based on the device type.
            DefaultDeviceType = HDA_VERB_GET_CONFIGURATION_DEFAULT_DEVICE(HdaWidget->DefaultConfiguration);
            if ((DefaultDeviceType == HDA_CONFIG_DEFAULT_DEVICE_LINE_OUT) || (DefaultDeviceType == HDA_CONFIG_DEFAULT_DEVICE_SPEAKER) ||
                (DefaultDeviceType == HDA_CONFIG_DEFAULT_DEVICE_HEADPHONE_OUT) || (DefaultDeviceType == HDA_CONFIG_DEFAULT_DEVICE_SPDIF_OUT) ||
                (DefaultDeviceType == HDA_CONFIG_DEFAULT_DEVICE_OTHER_DIGITAL_OUT)) {

                // Try to get upstream output.
                DEBUG((DEBUG_INFO, "Port widget @ 0x%X is an output (pin defaults 0x%X)\n", HdaWidget->NodeId, HdaWidget->DefaultConfiguration));
                Status = HdaCodecFindUpstreamOutput(HdaWidget, 0);
                if (EFI_ERROR(Status))
                    continue;

                // Enable output amp.
                Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_PIN_WIDGET_CONTROL,
                    HDA_VERB_SET_PIN_WIDGET_CONTROL_PAYLOAD(0, FALSE, FALSE, TRUE, FALSE)), &Response);
                if (EFI_ERROR(Status))
                    continue;

                // If EAPD is present, enable.
                if (HdaWidget->PinCapabilities & HDA_PARAMETER_PIN_CAPS_EAPD) {
                    // Get current EAPD setting.
                    Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_GET_EAPD_BTL_ENABLE, 0), &Response);
                    if (EFI_ERROR(Status))
                        return Status;

                    // If the EAPD is not set, set it.
                    if (!(Response & HDA_EAPD_BTL_ENABLE_EAPD)) {
                        Response |= HDA_EAPD_BTL_ENABLE_EAPD;
                        Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_EAPD_BTL_ENABLE,
                            (UINT8)Response), &Response);
                        if (EFI_ERROR(Status))
                            return Status;
                    }
                }

                // If the output amp supports muting, unmute.
                if (HdaWidget->AmpOutCapabilities & HDA_PARAMETER_AMP_CAPS_MUTE) {
                    UINT8 offset = HDA_PARAMETER_AMP_CAPS_OFFSET(HdaWidget->AmpOutCapabilities); // TODO set volume.

                    // If there are no overriden amp capabilities, check function group.
                    if (!(HdaWidget->AmpOverride))
                        offset = HDA_PARAMETER_AMP_CAPS_OFFSET(HdaWidget->FuncGroup->AmpOutCapabilities);

                    // Unmute amp.
                    Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_AMP_GAIN_MUTE,
                        HDA_VERB_SET_AMP_GAIN_MUTE_PAYLOAD(0, offset, FALSE, TRUE, TRUE, FALSE, TRUE)), &Response);
                    if (EFI_ERROR(Status))
                        return Status;
                }

                // Reallocate output array.
                HdaCodecDev->OutputPorts = ReallocatePool(sizeof(HDA_WIDGET_DEV*) * HdaCodecDev->OutputPortsCount, sizeof(HDA_WIDGET_DEV*) * (HdaCodecDev->OutputPortsCount + 1), HdaCodecDev->OutputPorts);
                if (HdaCodecDev->OutputPorts == NULL)
                    return EFI_OUT_OF_RESOURCES;
                HdaCodecDev->OutputPortsCount++;

                // Add widget to output array.
                HdaCodecDev->OutputPorts[HdaCodecDev->OutputPortsCount - 1] = HdaWidget;
            }
        }
    }

    // Wait 1000ms for all widgets to fully come on.
    gBS->Stall(MS_TO_MICROSECOND(1000));

    return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
HdaCodecInstallProtocols(
    IN HDA_CODEC_DEV *HdaCodecDev) {
    DEBUG((DEBUG_INFO, "HdaCodecInstallProtocols(): start\n"));

    // Create variables.
    EFI_STATUS Status;
    HDA_CODEC_INFO_PRIVATE_DATA *HdaCodecInfoData;
    AUDIO_IO_PRIVATE_DATA *AudioIoData;

    // Allocate space for protocol data.
    HdaCodecInfoData = AllocateZeroPool(sizeof(HDA_CODEC_INFO_PRIVATE_DATA));
    AudioIoData = AllocateZeroPool(sizeof(AUDIO_IO_PRIVATE_DATA));
    if ((HdaCodecInfoData == NULL) || (AudioIoData == NULL)) {
        Status = EFI_OUT_OF_RESOURCES;
        goto FREE_POOLS;
    }

    // Populate info protocol data.
    HdaCodecInfoData->Signature = HDA_CODEC_PRIVATE_DATA_SIGNATURE;
    HdaCodecInfoData->HdaCodecDev = HdaCodecDev;
    HdaCodecInfoData->HdaCodecInfo.GetName = HdaCodecInfoGetCodecName;
    HdaCodecInfoData->HdaCodecInfo.GetVendorId = HdaCodecInfoGetVendorId;
    HdaCodecInfoData->HdaCodecInfo.GetRevisionId = HdaCodecInfoGetRevisionId;
    HdaCodecInfoData->HdaCodecInfo.GetAudioFuncId = HdaCodecInfoGetAudioFuncId;
    HdaCodecInfoData->HdaCodecInfo.GetDefaultRatesFormats = HdaCodecInfoGetDefaultRatesFormats;
    HdaCodecInfoData->HdaCodecInfo.GetDefaultAmpCaps = HdaCodecInfoGetDefaultAmpCaps;
    HdaCodecInfoData->HdaCodecInfo.GetWidgets = HdaCodecInfoGetWidgets;
    HdaCodecInfoData->HdaCodecInfo.FreeWidgetsBuffer = HdaCodecInfoFreeWidgetsBuffer;
    HdaCodecDev->HdaCodecInfoData = HdaCodecInfoData;

    // Populate I/O protocol data.
    AudioIoData->Signature = HDA_CODEC_PRIVATE_DATA_SIGNATURE;
    AudioIoData->HdaCodecDev = HdaCodecDev;
    AudioIoData->AudioIo.GetOutputs = HdaCodecAudioIoGetOutputs;
    AudioIoData->AudioIo.SetupPlayback = HdaCodecAudioIoSetupPlayback;
    AudioIoData->AudioIo.StartPlayback = HdaCodecAudioIoStartPlayback;
    AudioIoData->AudioIo.StartPlaybackAsync = HdaCodecAudioIoStartPlaybackAsync;
    AudioIoData->AudioIo.StopPlayback = HdaCodecAudioIoStopPlayback;
    HdaCodecDev->AudioIoData = AudioIoData;

    // Install protocols.
    Status = gBS->InstallMultipleProtocolInterfaces(&HdaCodecDev->ControllerHandle,
        &gEfiHdaCodecInfoProtocolGuid, &HdaCodecInfoData->HdaCodecInfo,
        &gEfiAudioIoProtocolGuid, &AudioIoData->AudioIo,
        &gEfiCallerIdGuid, HdaCodecDev, NULL);
    if (EFI_ERROR(Status))
        goto FREE_POOLS;
    return EFI_SUCCESS;

FREE_POOLS:
    if (HdaCodecInfoData != NULL)
        FreePool(HdaCodecInfoData);
    if (AudioIoData != NULL)
        FreePool(AudioIoData);
    return Status;
}

EFI_STATUS
EFIAPI
HdaCodecGetOutputDac(
    IN  HDA_WIDGET_DEV *HdaWidget,
    OUT HDA_WIDGET_DEV **HdaOutputWidget)
{
    DEBUG((DEBUG_INFO, "HdaCodecGetOutputDac(): start\n"));

    // Check that parameters are valid.
    if ((HdaWidget == NULL) || (HdaOutputWidget == NULL))
        return EFI_INVALID_PARAMETER;

    // Crawl through widget path looking for output DAC.
    while (HdaWidget != NULL) {
        // Is this widget an output DAC?
        if (HdaWidget->Type == HDA_WIDGET_TYPE_OUTPUT) {
            *HdaOutputWidget = HdaWidget;
            return EFI_SUCCESS;
        }

        // Move to upstream widget.
        HdaWidget = HdaWidget->UpstreamWidget;
    }

    // If we get here, we couldn't find the DAC.
    return EFI_NOT_FOUND;
}

EFI_STATUS
EFIAPI
HdaCodecGetSupportedPcmRates(
    IN  HDA_WIDGET_DEV *HdaPinWidget,
    OUT UINT32 *SupportedRates)
{
    EFI_STATUS Status;
    HDA_WIDGET_DEV *HdaOutputWidget;

//    DEBUG((DEBUG_INFO, "HdaCodecGetSupportedPcmRates(): start\n"));

    // Check that parameters are valid.
    if ((HdaPinWidget == NULL) || (SupportedRates == NULL))
        return EFI_INVALID_PARAMETER;

    // Get output DAC widget.
    Status = HdaCodecGetOutputDac(HdaPinWidget, &HdaOutputWidget);
    if (EFI_ERROR(Status))
        return Status;

    // Does the widget specify format info?
    if (HdaOutputWidget->Capabilities & HDA_PARAMETER_WIDGET_CAPS_FORMAT_OVERRIDE) {
        // Check widget for PCM support.
        if (!(HdaOutputWidget->SupportedFormats & HDA_PARAMETER_SUPPORTED_STREAM_FORMATS_PCM))
            return EFI_UNSUPPORTED;
        *SupportedRates = HdaOutputWidget->SupportedPcmRates;
    } else {
        // Check function group for PCM support.
        if (!(HdaOutputWidget->FuncGroup->SupportedFormats & HDA_PARAMETER_SUPPORTED_STREAM_FORMATS_PCM))
            return EFI_UNSUPPORTED;
        *SupportedRates = HdaOutputWidget->FuncGroup->SupportedPcmRates;
    }
    return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
HdaCodecDisableWidgetPath(
    IN HDA_WIDGET_DEV *HdaWidget)
{
    // Create variables.
    EFI_STATUS Status;
    EFI_HDA_IO_PROTOCOL *HdaIo = HdaWidget->FuncGroup->HdaCodecDev->HdaIo;
    UINT32 Response = 0;

    //DEBUG((DEBUG_INFO, "HdaCodecDisableWidgetPath(): start\n"));

    // Check if widget is valid.
    if (HdaWidget == NULL)
        return EFI_INVALID_PARAMETER;

    // Crawl through widget path.
    while (HdaWidget != NULL) {
        // If Output, disable stream.
        if (HdaWidget->Type == HDA_WIDGET_TYPE_OUTPUT) {
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_CONVERTER_STREAM_CHANNEL,
                HDA_VERB_SET_CONVERTER_STREAM_PAYLOAD(0, 0)), &Response);
            if (EFI_ERROR(Status))
                return Status;
        }

        //  If widget is a pin complex, disable output.
        if (HdaWidget->Type == HDA_WIDGET_TYPE_PIN_COMPLEX) {
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_PIN_WIDGET_CONTROL,
                HDA_VERB_SET_PIN_WIDGET_CONTROL_PAYLOAD(0, FALSE, FALSE, FALSE, FALSE)), &Response);
            if (EFI_ERROR(Status))
                return Status;
        }

        // Move to upstream widget.
        HdaWidget = HdaWidget->UpstreamWidget;
    }

    // Path disabled.
    return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
HdaCodecEnableWidgetPath(
    IN HDA_WIDGET_DEV *HdaWidget,
    IN UINT8 Volume,
    IN UINT8 StreamId,
    IN UINT16 StreamFormat)
{
    // Create variables.
    EFI_STATUS Status;
    EFI_HDA_IO_PROTOCOL *HdaIo = HdaWidget->FuncGroup->HdaCodecDev->HdaIo;
    UINT32 Response = 0;

    //DEBUG((DEBUG_INFO, "HdaCodecEnableWidgetPath(): start\n"));

    // Check if widget is valid.
    if ((HdaWidget == NULL) || (Volume > EFI_AUDIO_IO_PROTOCOL_MAX_VOLUME))
        return EFI_INVALID_PARAMETER;

     // Crawl through widget path.
    while (HdaWidget != NULL) {
        DEBUG((DEBUG_INFO, "Widget @ 0x%X setting up\n", HdaWidget->NodeId));

        // If pin complex, set as output.
        if (HdaWidget->Type == HDA_WIDGET_TYPE_PIN_COMPLEX) {
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_PIN_WIDGET_CONTROL,
                HDA_VERB_SET_PIN_WIDGET_CONTROL_PAYLOAD(0, FALSE, FALSE, TRUE, FALSE)), &Response);
            if (EFI_ERROR(Status))
                return Status;

            // If EAPD, enable.
            if (HdaWidget->PinCapabilities & HDA_PARAMETER_PIN_CAPS_EAPD) {
                // Get current EAPD setting.
                Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_GET_EAPD_BTL_ENABLE, 0), &Response);
                if (EFI_ERROR(Status))
                    return Status;

                // If the EAPD is not set, set it.
                if (!(Response & HDA_EAPD_BTL_ENABLE_EAPD)) {
                    Response |= HDA_EAPD_BTL_ENABLE_EAPD;
                    Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_EAPD_BTL_ENABLE,
                        (UINT8)Response), &Response);
                    if (EFI_ERROR(Status))
                        return Status;
                }
            }
        }

        // If this is a digital widget, enable digital output.
        if (HdaWidget->Capabilities & HDA_PARAMETER_WIDGET_CAPS_DIGITAL) {
            // Enable digital output.
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_DIGITAL_CONV_CONTROL1,
                HDA_DIGITAL_CONV_CONTROL_DIGEN), &Response);
            if (EFI_ERROR(Status))
                return Status;

            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_ASP_MAPPING,
                0x00), &Response);
            if (EFI_ERROR(Status))
                return Status;
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_ASP_MAPPING,
                0x11), &Response);
            if (EFI_ERROR(Status))
                return Status;
        }

        // If there is an output amp, unmute.
        if (HdaWidget->Capabilities & HDA_PARAMETER_WIDGET_CAPS_OUT_AMP) {
            UINT8 offset = HDA_PARAMETER_AMP_CAPS_OFFSET(HdaWidget->AmpOutCapabilities); // TODO set volume.

            // If there are no overriden amp capabilities, check function group.
            if (!(HdaWidget->AmpOverride))
                offset = HDA_PARAMETER_AMP_CAPS_OFFSET(HdaWidget->FuncGroup->AmpOutCapabilities);

            // Calculate offset.
            offset = (offset * Volume) / EFI_AUDIO_IO_PROTOCOL_MAX_VOLUME;
            DEBUG((DEBUG_INFO, "HdaCodecEnableWidgetPath(): Amp out offset 0x%X\n", offset));
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_AMP_GAIN_MUTE,
                HDA_VERB_SET_AMP_GAIN_MUTE_PAYLOAD(0, offset, FALSE, TRUE, TRUE, FALSE, TRUE)), &Response);
            if (EFI_ERROR(Status))
                return Status;
        }

        // If there are input amps, mute all but the upstream.
        if (HdaWidget->Capabilities & HDA_PARAMETER_WIDGET_CAPS_IN_AMP) {
            DEBUG((DEBUG_INFO, "Widget @ 0x%X in amp\n", HdaWidget->NodeId));
            for (UINT8 c = 0; c < HdaWidget->ConnectionCount; c++) {
                if (HdaWidget->UpstreamIndex == c) {
                    UINT8 offset = HDA_PARAMETER_AMP_CAPS_OFFSET(HdaWidget->AmpInCapabilities);
                    // If there are no overriden amp capabilities, check function group.
                    if (!(HdaWidget->AmpOverride))
                        offset = HDA_PARAMETER_AMP_CAPS_OFFSET(HdaWidget->FuncGroup->AmpInCapabilities);
                    Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_AMP_GAIN_MUTE,
                        HDA_VERB_SET_AMP_GAIN_MUTE_PAYLOAD(c, offset, FALSE, TRUE, TRUE, TRUE, FALSE)), &Response);
                    if (EFI_ERROR(Status))
                        return Status;
                } else {
                    Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_AMP_GAIN_MUTE,
                        HDA_VERB_SET_AMP_GAIN_MUTE_PAYLOAD(c, 0, TRUE, TRUE, TRUE, TRUE, FALSE)), &Response);
                    if (EFI_ERROR(Status))
                        return Status;
                }
            }
        }

        // If there is more than one connection, select our upstream.
        if (HdaWidget->ConnectionCount > 1) {
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_CONN_SELECT_CONTROL,
                HdaWidget->UpstreamIndex), &Response);
            if (EFI_ERROR(Status))
                return Status;
        }

        // If Output, set up stream.
        if (HdaWidget->Type == HDA_WIDGET_TYPE_OUTPUT) {
            DEBUG((DEBUG_INFO, "Widget @ 0x%X output\n", HdaWidget->NodeId));
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_CONVERTER_FORMAT,
                StreamFormat), &Response);
            if (EFI_ERROR(Status))
                return Status;
            Status = HdaIo->SendCommand(HdaIo, HdaWidget->NodeId, HDA_CODEC_VERB(HDA_VERB_SET_CONVERTER_STREAM_CHANNEL,
                HDA_VERB_SET_CONVERTER_STREAM_PAYLOAD(0, StreamId)), &Response);
            if (EFI_ERROR(Status))
                return Status;
        }

        // Move to upstream widget.
        HdaWidget = HdaWidget->UpstreamWidget;
    }
    return EFI_SUCCESS;
}

VOID
EFIAPI
HdaCodecCleanup(
    IN HDA_CODEC_DEV *HdaCodecDev)
{
//    DEBUG((DEBUG_INFO, "HdaCodecCleanup(): start\n"));

    // Create variables.
    EFI_STATUS Status;
    HDA_FUNC_GROUP *HdaFuncGroup;
    HDA_WIDGET_DEV *HdaWidget;

    // If codec is already clear, we are done.
    if (HdaCodecDev == NULL)
        return;

    // Clean HDA Codec Info protocol.
    if (HdaCodecDev->HdaCodecInfoData != NULL) {
        // Uninstall protocol.
        DEBUG((DEBUG_INFO, "HdaCodecCleanup(): clean Hda Codec Info\n"));
        Status = gBS->UninstallProtocolInterface(HdaCodecDev->ControllerHandle,
            &gEfiHdaCodecInfoProtocolGuid, &HdaCodecDev->HdaCodecInfoData->HdaCodecInfo);
        ASSERT_EFI_ERROR(Status);

        // Free data.
        FreePool(HdaCodecDev->HdaCodecInfoData);
    }

    // Clean Audio I/O protocol.
    if (HdaCodecDev->AudioIoData != NULL) {
        // Uninstall protocol.
        DEBUG((DEBUG_INFO, "HdaCodecCleanup(): clean Audio I/O\n"));
        Status = gBS->UninstallProtocolInterface(HdaCodecDev->ControllerHandle,
            &gEfiAudioIoProtocolGuid, &HdaCodecDev->AudioIoData->AudioIo);
        ASSERT_EFI_ERROR(Status);

        // Free data.
        FreePool(HdaCodecDev->AudioIoData);
    }

    // Clean up input and output port arrays.
    if (HdaCodecDev->OutputPorts != NULL)
        FreePool(HdaCodecDev->OutputPorts);
    if (HdaCodecDev->InputPorts != NULL)
        FreePool(HdaCodecDev->InputPorts);

    // Clean function groups.
    if (HdaCodecDev->FuncGroups != NULL) {
        // Clean each function group.
        for (UINT8 f = 0; f < HdaCodecDev->FuncGroupsCount; f++) {
            HdaFuncGroup = HdaCodecDev->FuncGroups + f;

            // Clean widgets in function group.
            if (HdaFuncGroup->Widgets != NULL) {
                for (UINT8 w = 0; w < HdaFuncGroup->WidgetsCount; w++) {
                    HdaWidget = HdaFuncGroup->Widgets + w;

                    // Clean input amp default arrays.
                    if (HdaWidget->AmpInLeftDefaultGainMute != NULL)
                        FreePool(HdaWidget->AmpInLeftDefaultGainMute);
                    if (HdaWidget->AmpInRightDefaultGainMute != NULL)
                        FreePool(HdaWidget->AmpInRightDefaultGainMute);

                    // Clean connections array.
                    if (HdaWidget->WidgetConnections != NULL)
                        FreePool(HdaWidget->WidgetConnections);
                    if (HdaWidget->Connections != NULL)
                        FreePool(HdaWidget->Connections);
                }

                // Free widgets array.
                FreePool(HdaFuncGroup->Widgets);
            }
        }

        // Free function group array.
        FreePool(HdaCodecDev->FuncGroups);
    }

    // Free codec device.
    gBS->UninstallProtocolInterface(HdaCodecDev->ControllerHandle,
        &gEfiCallerIdGuid, HdaCodecDev);
    FreePool(HdaCodecDev);
}

EFI_STATUS
EFIAPI
HdaCodecDriverBindingSupported(
    IN EFI_DRIVER_BINDING_PROTOCOL *This,
    IN EFI_HANDLE ControllerHandle,
    IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath OPTIONAL)
{

    // Create variables.
    EFI_STATUS Status;
    EFI_HDA_IO_PROTOCOL *HdaIo;
    UINT8 CodecAddress;

    // Attempt to open the HDA codec protocol. If it can be opened, we can support it.
    Status = gBS->OpenProtocol(ControllerHandle, &gEfiHdaIoProtocolGuid, (VOID**)&HdaIo,
        This->DriverBindingHandle, ControllerHandle, EFI_OPEN_PROTOCOL_BY_DRIVER);
    if (EFI_ERROR(Status))
        return Status;

    // Get address of codec.
    Status = HdaIo->GetAddress(HdaIo, &CodecAddress);
    if (EFI_ERROR(Status))
        goto CLOSE_CODEC;

    // Codec can be supported.
    DEBUG((DEBUG_INFO, "HdaCodecDriverBindingSupported(): attaching to codec 0x%X\n", CodecAddress));
    Status = EFI_SUCCESS;

CLOSE_CODEC:
    // Close protocol.
    gBS->CloseProtocol(ControllerHandle, &gEfiHdaIoProtocolGuid, This->DriverBindingHandle, ControllerHandle);
    return Status;
}

EFI_STATUS
EFIAPI
HdaCodecDriverBindingStart(
    IN EFI_DRIVER_BINDING_PROTOCOL *This,
    IN EFI_HANDLE ControllerHandle,
    IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath OPTIONAL)
{
//    DEBUG((DEBUG_INFO, "HdaCodecDriverBindingStart(): start\n"));

    // Create variables.
    EFI_STATUS Status;
    EFI_HDA_IO_PROTOCOL *HdaIo;
    EFI_DEVICE_PATH_PROTOCOL *HdaCodecDevicePath;
    HDA_CODEC_DEV *HdaCodecDev;

    // Open HDA I/O protocol.
    Status = gBS->OpenProtocol(ControllerHandle, &gEfiHdaIoProtocolGuid, (VOID**)&HdaIo,
        This->DriverBindingHandle, ControllerHandle, EFI_OPEN_PROTOCOL_BY_DRIVER);
    if (EFI_ERROR(Status))
        return Status;

    // Open Device Path protocol.
    Status = gBS->OpenProtocol(ControllerHandle, &gEfiDevicePathProtocolGuid, (VOID**)&HdaCodecDevicePath,
        This->DriverBindingHandle, ControllerHandle, EFI_OPEN_PROTOCOL_BY_DRIVER);
    if (EFI_ERROR (Status))
        goto CLOSE_CODEC;
    // Allocate codec device.
    HdaCodecDev = AllocateZeroPool(sizeof(HDA_CODEC_DEV));
    if (HdaCodecDev == NULL) {
        Status = EFI_OUT_OF_RESOURCES;
        goto CLOSE_CODEC;
    }

    // Fill codec device data.
    HdaCodecDev->Signature = HDA_CODEC_PRIVATE_DATA_SIGNATURE;
    HdaCodecDev->HdaIo = HdaIo;
    HdaCodecDev->DevicePath = HdaCodecDevicePath;
    HdaCodecDev->ControllerHandle = ControllerHandle;
    // Probe codec.
    Status = HdaCodecProbeCodec(HdaCodecDev);
    if (EFI_ERROR (Status))
        goto FREE_CODEC;

    // Get ports.
    Status = HdaCodecParsePorts(HdaCodecDev);
    if (EFI_ERROR (Status))
        goto FREE_CODEC;

    // Publish protocols.
    Status = HdaCodecInstallProtocols(HdaCodecDev);
    ASSERT_EFI_ERROR(Status);
    if (EFI_ERROR (Status))
        goto FREE_CODEC;

    // Success.
    return EFI_SUCCESS;

FREE_CODEC:
    // Cleanup codec.
    HdaCodecCleanup(HdaCodecDev);

CLOSE_CODEC:
    // Close protocols.
    gBS->CloseProtocol(ControllerHandle, &gEfiDevicePathProtocolGuid, This->DriverBindingHandle, ControllerHandle);
    gBS->CloseProtocol(ControllerHandle, &gEfiHdaIoProtocolGuid, This->DriverBindingHandle, ControllerHandle);
    return Status;
}

EFI_STATUS
EFIAPI
HdaCodecDriverBindingStop(
    IN EFI_DRIVER_BINDING_PROTOCOL *This,
    IN EFI_HANDLE ControllerHandle,
    IN UINTN NumberOfChildren,
    IN EFI_HANDLE *ChildHandleBuffer OPTIONAL)
{
//    DEBUG((DEBUG_INFO, "HdaCodecDriverBindingStop(): start\n"));

    // Create variables.
    EFI_STATUS Status;
    HDA_CODEC_DEV *HdaCodecDev;

    // Get codec device.
    Status = gBS->OpenProtocol(ControllerHandle, &gEfiCallerIdGuid, (VOID**)&HdaCodecDev,
        This->DriverBindingHandle, ControllerHandle, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
    if (!(EFI_ERROR(Status))) {
        // Ensure codec device is valid.
        if (HdaCodecDev->Signature != HDA_CODEC_PRIVATE_DATA_SIGNATURE)
            return EFI_INVALID_PARAMETER;

        // Cleanup codec.
        HdaCodecCleanup(HdaCodecDev);
    }

    // Close protocols.
    gBS->CloseProtocol(ControllerHandle, &gEfiDevicePathProtocolGuid, This->DriverBindingHandle, ControllerHandle);
    gBS->CloseProtocol(ControllerHandle, &gEfiHdaIoProtocolGuid, This->DriverBindingHandle, ControllerHandle);
    return EFI_SUCCESS;
}