// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2022-2025 Qualcomm Innovation Center, Inc. All rights reserved.
 */

#include <linux/auxiliary_bus.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/dma-map-ops.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/iommu.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

#include <sound/asound.h>
#include <sound/jack.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/q6usboffload.h>
#include <sound/soc.h>
#include <sound/soc-usb.h>

#include <dt-bindings/sound/qcom,q6afe.h>

#include "q6afe.h"
#include "q6dsp-lpass-ports.h"

#define Q6_USB_SID_MASK 0xF

struct q6usb_port_data {
        struct auxiliary_device uauxdev;
        struct q6afe_usb_cfg usb_cfg;
        struct snd_soc_usb *usb;
        struct snd_soc_jack *hs_jack;
        struct q6usb_offload priv;

        /* Protects against operations between SOC USB and ASoC */
        struct mutex mutex;
        struct list_head devices;
};

static const struct snd_soc_dapm_widget q6usb_dai_widgets[] = {
        SND_SOC_DAPM_HP("USB_RX_BE", NULL),
};

static const struct snd_soc_dapm_route q6usb_dapm_routes[] = {
        {"USB Playback", NULL, "USB_RX_BE"},
};

static int q6usb_hw_params(struct snd_pcm_substream *substream,
                           struct snd_pcm_hw_params *params,
                           struct snd_soc_dai *dai)
{
        struct q6usb_port_data *data = dev_get_drvdata(dai->dev);
        struct snd_soc_pcm_runtime *rtd = substream->private_data;
        struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
        int direction = substream->stream;
        struct q6afe_port *q6usb_afe;
        struct snd_soc_usb_device *sdev;
        int ret = -EINVAL;

        mutex_lock(&data->mutex);

        /* No active chip index */
        if (list_empty(&data->devices))
                goto out;

        sdev = list_last_entry(&data->devices, struct snd_soc_usb_device, list);

        ret = snd_soc_usb_find_supported_format(sdev->chip_idx, params, direction);
        if (ret < 0)
                goto out;

        q6usb_afe = q6afe_port_get_from_id(cpu_dai->dev, USB_RX);
        if (IS_ERR(q6usb_afe)) {
                ret = PTR_ERR(q6usb_afe);
                goto out;
        }

        /* Notify audio DSP about the devices being offloaded */
        ret = afe_port_send_usb_dev_param(q6usb_afe, sdev->card_idx,
                                          sdev->ppcm_idx[sdev->num_playback - 1]);

out:
        mutex_unlock(&data->mutex);

        return ret;
}

static const struct snd_soc_dai_ops q6usb_ops = {
        .hw_params = q6usb_hw_params,
};

static struct snd_soc_dai_driver q6usb_be_dais[] = {
        {
                .playback = {
                        .stream_name = "USB BE RX",
                        .rates = SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_11025 |
                                SNDRV_PCM_RATE_16000 | SNDRV_PCM_RATE_22050 |
                                SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 |
                                SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_96000 |
                                SNDRV_PCM_RATE_192000,
                        .formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S16_BE |
                                SNDRV_PCM_FMTBIT_U16_LE | SNDRV_PCM_FMTBIT_U16_BE |
                                SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S24_BE |
                                SNDRV_PCM_FMTBIT_U24_LE | SNDRV_PCM_FMTBIT_U24_BE,
                        .channels_min = 1,
                        .channels_max = 2,
                        .rate_max =     192000,
                        .rate_min =     8000,
                },
                .id = USB_RX,
                .name = "USB_RX_BE",
                .ops = &q6usb_ops,
        },
};

static int q6usb_audio_ports_of_xlate_dai_name(struct snd_soc_component *component,
                                               const struct of_phandle_args *args,
                                               const char **dai_name)
{
        int id = args->args[0];
        int ret = -EINVAL;
        int i;

        for (i = 0; i < ARRAY_SIZE(q6usb_be_dais); i++) {
                if (q6usb_be_dais[i].id == id) {
                        *dai_name = q6usb_be_dais[i].name;
                        ret = 0;
                        break;
                }
        }

        return ret;
}

static int q6usb_get_pcm_id_from_widget(struct snd_soc_dapm_widget *w)
{
        struct snd_soc_card *card = snd_soc_dapm_to_card(w->dapm);
        struct snd_soc_pcm_runtime *rtd;
        struct snd_soc_dai *dai;

        for_each_card_rtds(card, rtd) {
                dai = snd_soc_rtd_to_cpu(rtd, 0);
                /*
                 * Only look for playback widget. RTD number carries the assigned
                 * PCM index.
                 */
                if (dai->stream[0].widget == w)
                        return rtd->id;
        }

        return -1;
}

static int q6usb_usb_mixer_enabled(struct snd_soc_dapm_widget *w)
{
        struct snd_soc_dapm_path *p;

        /* Checks to ensure USB path is enabled/connected */
        snd_soc_dapm_widget_for_each_sink_path(w, p)
                if (!strcmp(p->sink->name, "USB Mixer") && p->connect)
                        return 1;

        return 0;
}

static int q6usb_get_pcm_id(struct snd_soc_component *component)
{
        struct snd_soc_dapm_widget *w;
        struct snd_soc_dapm_path *p;
        int pidx;

        /*
         * Traverse widgets to find corresponding FE widget.  The DAI links are
         * built like the following:
         *    MultiMedia* <-> MM_DL* <-> USB Mixer*
         */
        for_each_card_widgets(component->card, w) {
                if (!strncmp(w->name, "MultiMedia", 10)) {
                        /*
                         * Look up all paths associated with the FE widget to see if
                         * the USB BE is enabled.  The sink widget is responsible to
                         * link with the USB mixers.
                         */
                        snd_soc_dapm_widget_for_each_sink_path(w, p) {
                                if (q6usb_usb_mixer_enabled(p->sink)) {
                                        pidx = q6usb_get_pcm_id_from_widget(w);
                                        return pidx;
                                }
                        }
                }
        }

        return -1;
}

static int q6usb_update_offload_route(struct snd_soc_component *component, int card,
                                      int pcm, int direction, enum snd_soc_usb_kctl path,
                                      long *route)
{
        struct q6usb_port_data *data = dev_get_drvdata(component->dev);
        struct snd_soc_usb_device *sdev;
        int ret = 0;
        int idx = -1;

        mutex_lock(&data->mutex);

        if (list_empty(&data->devices) ||
            direction == SNDRV_PCM_STREAM_CAPTURE) {
                ret = -ENODEV;
                goto out;
        }

        sdev = list_last_entry(&data->devices, struct snd_soc_usb_device, list);

        /*
         * Will always look for last PCM device discovered/probed as the
         * active offload index.
         */
        if (card == sdev->card_idx &&
            pcm == sdev->ppcm_idx[sdev->num_playback - 1]) {
                idx = path == SND_SOC_USB_KCTL_CARD_ROUTE ?
                                component->card->snd_card->number :
                                q6usb_get_pcm_id(component);
        }

out:
        route[0] = idx;
        mutex_unlock(&data->mutex);

        return ret;
}

static int q6usb_alsa_connection_cb(struct snd_soc_usb *usb,
                                    struct snd_soc_usb_device *sdev, bool connected)
{
        struct q6usb_port_data *data;

        if (!usb->component)
                return -ENODEV;

        data = dev_get_drvdata(usb->component->dev);

        mutex_lock(&data->mutex);
        if (connected) {
                if (data->hs_jack)
                        snd_jack_report(data->hs_jack->jack, SND_JACK_USB);

                /* Selects the latest USB headset plugged in for offloading */
                list_add_tail(&sdev->list, &data->devices);
        } else {
                list_del(&sdev->list);

                if (data->hs_jack)
                        snd_jack_report(data->hs_jack->jack, 0);
        }
        mutex_unlock(&data->mutex);

        return 0;
}

static void q6usb_component_disable_jack(struct q6usb_port_data *data)
{
        /* Offload jack has already been disabled */
        if (!data->hs_jack)
                return;

        snd_jack_report(data->hs_jack->jack, 0);
        data->hs_jack = NULL;
}

static void q6usb_component_enable_jack(struct q6usb_port_data *data,
                                        struct snd_soc_jack *jack)
{
        snd_jack_report(jack->jack, !list_empty(&data->devices) ? SND_JACK_USB : 0);
        data->hs_jack = jack;
}

static int q6usb_component_set_jack(struct snd_soc_component *component,
                                    struct snd_soc_jack *jack, void *priv)
{
        struct q6usb_port_data *data = dev_get_drvdata(component->dev);

        mutex_lock(&data->mutex);
        if (jack)
                q6usb_component_enable_jack(data, jack);
        else
                q6usb_component_disable_jack(data);
        mutex_unlock(&data->mutex);

        return 0;
}

static void q6usb_dai_aux_release(struct device *dev) {}

static int q6usb_dai_add_aux_device(struct q6usb_port_data *data,
                                    struct auxiliary_device *auxdev)
{
        int ret;

        auxdev->dev.parent = data->priv.dev;
        auxdev->dev.release = q6usb_dai_aux_release;
        auxdev->name = "qc-usb-audio-offload";

        ret = auxiliary_device_init(auxdev);
        if (ret)
                return ret;

        ret = auxiliary_device_add(auxdev);
        if (ret)
                auxiliary_device_uninit(auxdev);

        return ret;
}

static int q6usb_component_probe(struct snd_soc_component *component)
{
        struct q6usb_port_data *data = dev_get_drvdata(component->dev);
        struct snd_soc_usb *usb;
        int ret;

        /* Add the QC USB SND aux device */
        ret = q6usb_dai_add_aux_device(data, &data->uauxdev);
        if (ret < 0)
                return ret;

        usb = snd_soc_usb_allocate_port(component, &data->priv);
        if (IS_ERR(usb))
                return -ENOMEM;

        usb->connection_status_cb = q6usb_alsa_connection_cb;
        usb->update_offload_route_info = q6usb_update_offload_route;

        snd_soc_usb_add_port(usb);
        data->usb = usb;

        return 0;
}

static void q6usb_component_remove(struct snd_soc_component *component)
{
        struct q6usb_port_data *data = dev_get_drvdata(component->dev);

        snd_soc_usb_remove_port(data->usb);
        auxiliary_device_delete(&data->uauxdev);
        auxiliary_device_uninit(&data->uauxdev);
        snd_soc_usb_free_port(data->usb);
}

static const struct snd_soc_component_driver q6usb_dai_component = {
        .probe = q6usb_component_probe,
        .set_jack = q6usb_component_set_jack,
        .remove = q6usb_component_remove,
        .name = "q6usb-dai-component",
        .dapm_widgets = q6usb_dai_widgets,
        .num_dapm_widgets = ARRAY_SIZE(q6usb_dai_widgets),
        .dapm_routes = q6usb_dapm_routes,
        .num_dapm_routes = ARRAY_SIZE(q6usb_dapm_routes),
        .of_xlate_dai_name = q6usb_audio_ports_of_xlate_dai_name,
};

static int q6usb_dai_dev_probe(struct platform_device *pdev)
{
        struct device_node *node = pdev->dev.of_node;
        struct q6usb_port_data *data;
        struct device *dev = &pdev->dev;
        struct of_phandle_args args;
        int ret;

        data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
        if (!data)
                return -ENOMEM;

        ret = of_property_read_u16(node, "qcom,usb-audio-intr-idx",
                                   &data->priv.intr_num);
        if (ret) {
                dev_err(&pdev->dev, "failed to read intr idx.\n");
                return ret;
        }

        ret = of_parse_phandle_with_fixed_args(node, "iommus", 1, 0, &args);
        if (!ret)
                data->priv.sid = args.args[0] & Q6_USB_SID_MASK;

        ret = devm_mutex_init(dev, &data->mutex);
        if (ret < 0)
                return ret;

        data->priv.domain = iommu_get_domain_for_dev(&pdev->dev);

        data->priv.dev = dev;
        INIT_LIST_HEAD(&data->devices);
        dev_set_drvdata(dev, data);

        return devm_snd_soc_register_component(dev, &q6usb_dai_component,
                                        q6usb_be_dais, ARRAY_SIZE(q6usb_be_dais));
}

static const struct of_device_id q6usb_dai_device_id[] = {
        { .compatible = "qcom,q6usb" },
        {},
};
MODULE_DEVICE_TABLE(of, q6usb_dai_device_id);

static struct platform_driver q6usb_dai_platform_driver = {
        .driver = {
                .name = "q6usb-dai",
                .of_match_table = q6usb_dai_device_id,
        },
        .probe = q6usb_dai_dev_probe,
        /*
         * Remove not required as resources are cleaned up as part of
         * component removal.  Others are device managed resources.
         */
};
module_platform_driver(q6usb_dai_platform_driver);

MODULE_DESCRIPTION("Q6 USB backend dai driver");
MODULE_LICENSE("GPL");