root/sound/soc/codecs/cros_ec_codec.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright 2019 Google, Inc.
 *
 * ChromeOS Embedded Controller codec driver.
 *
 * This driver uses the cros-ec interface to communicate with the ChromeOS
 * EC for audio function.
 */

#include <crypto/sha2.h>
#include <linux/acpi.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_reserved_mem.h>
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
#include <linux/platform_device.h>
#include <linux/string_choices.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <sound/tlv.h>

struct cros_ec_codec_priv {
        struct device *dev;
        struct cros_ec_device *ec_device;

        /* common */
        uint32_t ec_capabilities;

        uint64_t ec_shm_addr;
        uint32_t ec_shm_len;

        uint64_t ap_shm_phys_addr;
        uint32_t ap_shm_len;
        uint64_t ap_shm_addr;
        uint64_t ap_shm_last_alloc;

        /* DMIC */
        atomic_t dmic_probed;

        /* I2S_RX */
        uint32_t i2s_rx_bclk_ratio;

        /* WoV */
        bool wov_enabled;
        uint8_t *wov_audio_shm_p;
        uint32_t wov_audio_shm_len;
        uint8_t wov_audio_shm_type;
        uint8_t *wov_lang_shm_p;
        uint32_t wov_lang_shm_len;
        uint8_t wov_lang_shm_type;

        struct mutex wov_dma_lock;
        uint8_t wov_buf[64000];
        uint32_t wov_rp, wov_wp;
        size_t wov_dma_offset;
        bool wov_burst_read;
        struct snd_pcm_substream *wov_substream;
        struct delayed_work wov_copy_work;
        struct notifier_block wov_notifier;
};

static int ec_codec_capable(struct cros_ec_codec_priv *priv, uint8_t cap)
{
        return priv->ec_capabilities & BIT(cap);
}

static int send_ec_host_command(struct cros_ec_device *ec_dev, uint32_t cmd,
                                uint8_t *out, size_t outsize,
                                uint8_t *in, size_t insize)
{
        int ret;
        struct cros_ec_command *msg;

        msg = kmalloc(sizeof(*msg) + max(outsize, insize), GFP_KERNEL);
        if (!msg)
                return -ENOMEM;

        msg->version = 0;
        msg->command = cmd;
        msg->outsize = outsize;
        msg->insize = insize;

        if (outsize)
                memcpy(msg->data, out, outsize);

        ret = cros_ec_cmd_xfer_status(ec_dev, msg);
        if (ret < 0)
                goto error;

        if (in && insize)
                memcpy(in, msg->data, insize);

        ret = 0;
error:
        kfree(msg);
        return ret;
}

static int dmic_get_gain(struct snd_kcontrol *kcontrol,
                         struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);
        struct ec_param_ec_codec_dmic p;
        struct ec_response_ec_codec_dmic_get_gain_idx r;
        int ret;

        p.cmd = EC_CODEC_DMIC_GET_GAIN_IDX;
        p.get_gain_idx_param.channel = EC_CODEC_DMIC_CHANNEL_0;
        ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_DMIC,
                                   (uint8_t *)&p, sizeof(p),
                                   (uint8_t *)&r, sizeof(r));
        if (ret < 0)
                return ret;
        ucontrol->value.integer.value[0] = r.gain;

        p.cmd = EC_CODEC_DMIC_GET_GAIN_IDX;
        p.get_gain_idx_param.channel = EC_CODEC_DMIC_CHANNEL_1;
        ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_DMIC,
                                   (uint8_t *)&p, sizeof(p),
                                   (uint8_t *)&r, sizeof(r));
        if (ret < 0)
                return ret;
        ucontrol->value.integer.value[1] = r.gain;

        return 0;
}

static int dmic_put_gain(struct snd_kcontrol *kcontrol,
                         struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);
        struct soc_mixer_control *control =
                (struct soc_mixer_control *)kcontrol->private_value;
        int max_dmic_gain = control->max;
        int left = ucontrol->value.integer.value[0];
        int right = ucontrol->value.integer.value[1];
        struct ec_param_ec_codec_dmic p;
        int ret;

        if (left > max_dmic_gain || right > max_dmic_gain)
                return -EINVAL;

        dev_dbg(component->dev, "set mic gain to %u, %u\n", left, right);

        p.cmd = EC_CODEC_DMIC_SET_GAIN_IDX;
        p.set_gain_idx_param.channel = EC_CODEC_DMIC_CHANNEL_0;
        p.set_gain_idx_param.gain = left;
        ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_DMIC,
                                   (uint8_t *)&p, sizeof(p), NULL, 0);
        if (ret < 0)
                return ret;

        p.cmd = EC_CODEC_DMIC_SET_GAIN_IDX;
        p.set_gain_idx_param.channel = EC_CODEC_DMIC_CHANNEL_1;
        p.set_gain_idx_param.gain = right;
        return send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_DMIC,
                                    (uint8_t *)&p, sizeof(p), NULL, 0);
}

static const DECLARE_TLV_DB_SCALE(dmic_gain_tlv, 0, 100, 0);

enum {
        DMIC_CTL_GAIN = 0,
};

static struct snd_kcontrol_new dmic_controls[] = {
        [DMIC_CTL_GAIN] =
                SOC_DOUBLE_EXT_TLV("EC Mic Gain", SND_SOC_NOPM, SND_SOC_NOPM,
                                   0, 0, 0, dmic_get_gain, dmic_put_gain,
                                   dmic_gain_tlv),
};

static int dmic_probe(struct snd_soc_component *component)
{
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);
        struct device *dev = priv->dev;
        struct soc_mixer_control *control;
        struct ec_param_ec_codec_dmic p;
        struct ec_response_ec_codec_dmic_get_max_gain r;
        int ret;

        if (!atomic_add_unless(&priv->dmic_probed, 1, 1))
                return 0;

        p.cmd = EC_CODEC_DMIC_GET_MAX_GAIN;

        ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_DMIC,
                                   (uint8_t *)&p, sizeof(p),
                                   (uint8_t *)&r, sizeof(r));
        if (ret < 0) {
                dev_warn(dev, "get_max_gain() unsupported\n");
                return 0;
        }

        dev_dbg(dev, "max gain = %d\n", r.max_gain);

        control = (struct soc_mixer_control *)
                dmic_controls[DMIC_CTL_GAIN].private_value;
        control->max = r.max_gain;
        control->platform_max = r.max_gain;

        return snd_soc_add_component_controls(component,
                        &dmic_controls[DMIC_CTL_GAIN], 1);
}

static int i2s_rx_hw_params(struct snd_pcm_substream *substream,
                            struct snd_pcm_hw_params *params,
                            struct snd_soc_dai *dai)
{
        struct snd_soc_component *component = dai->component;
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);
        struct ec_param_ec_codec_i2s_rx p;
        enum ec_codec_i2s_rx_sample_depth depth;
        uint32_t bclk;
        int ret;

        if (params_rate(params) != 48000)
                return -EINVAL;

        switch (params_width(params)) {
        case 16:
                depth = EC_CODEC_I2S_RX_SAMPLE_DEPTH_16;
                break;
        case 24:
                depth = EC_CODEC_I2S_RX_SAMPLE_DEPTH_24;
                break;
        default:
                return -EINVAL;
        }

        dev_dbg(component->dev, "set depth to %u\n", depth);

        p.cmd = EC_CODEC_I2S_RX_SET_SAMPLE_DEPTH;
        p.set_sample_depth_param.depth = depth;
        ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_I2S_RX,
                                   (uint8_t *)&p, sizeof(p), NULL, 0);
        if (ret < 0)
                return ret;

        if (priv->i2s_rx_bclk_ratio)
                bclk = params_rate(params) * priv->i2s_rx_bclk_ratio;
        else
                bclk = snd_soc_params_to_bclk(params);

        dev_dbg(component->dev, "set bclk to %u\n", bclk);

        p.cmd = EC_CODEC_I2S_RX_SET_BCLK;
        p.set_bclk_param.bclk = bclk;
        return send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_I2S_RX,
                                    (uint8_t *)&p, sizeof(p), NULL, 0);
}

static int i2s_rx_set_bclk_ratio(struct snd_soc_dai *dai, unsigned int ratio)
{
        struct snd_soc_component *component = dai->component;
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);

        priv->i2s_rx_bclk_ratio = ratio;
        return 0;
}

static int i2s_rx_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
{
        struct snd_soc_component *component = dai->component;
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);
        struct ec_param_ec_codec_i2s_rx p;
        enum ec_codec_i2s_rx_daifmt daifmt;

        switch (fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
        case SND_SOC_DAIFMT_CBC_CFC:
                break;
        default:
                return -EINVAL;
        }

        switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
        case SND_SOC_DAIFMT_NB_NF:
                break;
        default:
                return -EINVAL;
        }

        switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
        case SND_SOC_DAIFMT_I2S:
                daifmt = EC_CODEC_I2S_RX_DAIFMT_I2S;
                break;
        case SND_SOC_DAIFMT_RIGHT_J:
                daifmt = EC_CODEC_I2S_RX_DAIFMT_RIGHT_J;
                break;
        case SND_SOC_DAIFMT_LEFT_J:
                daifmt = EC_CODEC_I2S_RX_DAIFMT_LEFT_J;
                break;
        default:
                return -EINVAL;
        }

        dev_dbg(component->dev, "set format to %u\n", daifmt);

        p.cmd = EC_CODEC_I2S_RX_SET_DAIFMT;
        p.set_daifmt_param.daifmt = daifmt;
        return send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_I2S_RX,
                                    (uint8_t *)&p, sizeof(p), NULL, 0);
}

static const struct snd_soc_dai_ops i2s_rx_dai_ops = {
        .hw_params = i2s_rx_hw_params,
        .set_fmt = i2s_rx_set_fmt,
        .set_bclk_ratio = i2s_rx_set_bclk_ratio,
};

static int i2s_rx_event(struct snd_soc_dapm_widget *w,
                        struct snd_kcontrol *kcontrol, int event)
{
        struct snd_soc_component *component =
                snd_soc_dapm_to_component(w->dapm);
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);
        struct ec_param_ec_codec_i2s_rx p = {};

        switch (event) {
        case SND_SOC_DAPM_PRE_PMU:
                dev_dbg(component->dev, "enable I2S RX\n");
                p.cmd = EC_CODEC_I2S_RX_ENABLE;
                break;
        case SND_SOC_DAPM_PRE_PMD:
                dev_dbg(component->dev, "disable I2S RX\n");
                p.cmd = EC_CODEC_I2S_RX_DISABLE;
                break;
        default:
                return 0;
        }

        return send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_I2S_RX,
                                    (uint8_t *)&p, sizeof(p), NULL, 0);
}

static struct snd_soc_dapm_widget i2s_rx_dapm_widgets[] = {
        SND_SOC_DAPM_INPUT("DMIC"),
        SND_SOC_DAPM_SUPPLY("I2S RX Enable", SND_SOC_NOPM, 0, 0, i2s_rx_event,
                            SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_PRE_PMD),
        SND_SOC_DAPM_AIF_OUT("I2S RX", "I2S Capture", 0, SND_SOC_NOPM, 0, 0),
};

static struct snd_soc_dapm_route i2s_rx_dapm_routes[] = {
        {"I2S RX", NULL, "DMIC"},
        {"I2S RX", NULL, "I2S RX Enable"},
};

static struct snd_soc_dai_driver i2s_rx_dai_driver = {
        .name = "EC Codec I2S RX",
        .capture = {
                .stream_name = "I2S Capture",
                .channels_min = 2,
                .channels_max = 2,
                .rates = SNDRV_PCM_RATE_48000,
                .formats = SNDRV_PCM_FMTBIT_S16_LE |
                        SNDRV_PCM_FMTBIT_S24_LE,
        },
        .ops = &i2s_rx_dai_ops,
};

static int i2s_rx_probe(struct snd_soc_component *component)
{
        return dmic_probe(component);
}

static const struct snd_soc_component_driver i2s_rx_component_driver = {
        .probe                  = i2s_rx_probe,
        .dapm_widgets           = i2s_rx_dapm_widgets,
        .num_dapm_widgets       = ARRAY_SIZE(i2s_rx_dapm_widgets),
        .dapm_routes            = i2s_rx_dapm_routes,
        .num_dapm_routes        = ARRAY_SIZE(i2s_rx_dapm_routes),
        .endianness             = 1,
};

static void *wov_map_shm(struct cros_ec_codec_priv *priv,
                         uint8_t shm_id, uint32_t *len, uint8_t *type)
{
        struct ec_param_ec_codec p;
        struct ec_response_ec_codec_get_shm_addr r;
        uint32_t req, offset;

        p.cmd = EC_CODEC_GET_SHM_ADDR;
        p.get_shm_addr_param.shm_id = shm_id;
        if (send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC,
                                 (uint8_t *)&p, sizeof(p),
                                 (uint8_t *)&r, sizeof(r)) < 0) {
                dev_err(priv->dev, "failed to EC_CODEC_GET_SHM_ADDR\n");
                return NULL;
        }

        dev_dbg(priv->dev, "phys_addr=%#llx, len=%#x\n", r.phys_addr, r.len);

        *len = r.len;
        *type = r.type;

        switch (r.type) {
        case EC_CODEC_SHM_TYPE_EC_RAM:
                return (void __force *)devm_ioremap_wc(priv->dev,
                                r.phys_addr + priv->ec_shm_addr, r.len);
        case EC_CODEC_SHM_TYPE_SYSTEM_RAM:
                if (r.phys_addr) {
                        dev_err(priv->dev, "unknown status\n");
                        return NULL;
                }

                req = round_up(r.len, PAGE_SIZE);
                dev_dbg(priv->dev, "round up from %u to %u\n", r.len, req);

                if (priv->ap_shm_last_alloc + req >
                    priv->ap_shm_phys_addr + priv->ap_shm_len) {
                        dev_err(priv->dev, "insufficient space for AP SHM\n");
                        return NULL;
                }

                dev_dbg(priv->dev, "alloc AP SHM addr=%#llx, len=%#x\n",
                        priv->ap_shm_last_alloc, req);

                p.cmd = EC_CODEC_SET_SHM_ADDR;
                p.set_shm_addr_param.phys_addr = priv->ap_shm_last_alloc;
                p.set_shm_addr_param.len = req;
                p.set_shm_addr_param.shm_id = shm_id;
                if (send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC,
                                         (uint8_t *)&p, sizeof(p),
                                         NULL, 0) < 0) {
                        dev_err(priv->dev, "failed to EC_CODEC_SET_SHM_ADDR\n");
                        return NULL;
                }

                /*
                 * Note: EC codec only requests for `r.len' but we allocate
                 * round up PAGE_SIZE `req'.
                 */
                offset = priv->ap_shm_last_alloc - priv->ap_shm_phys_addr;
                priv->ap_shm_last_alloc += req;

                return (void *)(uintptr_t)(priv->ap_shm_addr + offset);
        default:
                return NULL;
        }
}

static bool wov_queue_full(struct cros_ec_codec_priv *priv)
{
        return ((priv->wov_wp + 1) % sizeof(priv->wov_buf)) == priv->wov_rp;
}

static size_t wov_queue_size(struct cros_ec_codec_priv *priv)
{
        if (priv->wov_wp >= priv->wov_rp)
                return priv->wov_wp - priv->wov_rp;
        else
                return sizeof(priv->wov_buf) - priv->wov_rp + priv->wov_wp;
}

static void wov_queue_dequeue(struct cros_ec_codec_priv *priv, size_t len)
{
        struct snd_pcm_runtime *runtime = priv->wov_substream->runtime;
        size_t req;

        while (len) {
                req = min(len, runtime->dma_bytes - priv->wov_dma_offset);
                if (priv->wov_wp >= priv->wov_rp)
                        req = min(req, (size_t)priv->wov_wp - priv->wov_rp);
                else
                        req = min(req, sizeof(priv->wov_buf) - priv->wov_rp);

                memcpy(runtime->dma_area + priv->wov_dma_offset,
                       priv->wov_buf + priv->wov_rp, req);

                priv->wov_dma_offset += req;
                if (priv->wov_dma_offset == runtime->dma_bytes)
                        priv->wov_dma_offset = 0;

                priv->wov_rp += req;
                if (priv->wov_rp == sizeof(priv->wov_buf))
                        priv->wov_rp = 0;

                len -= req;
        }

        snd_pcm_period_elapsed(priv->wov_substream);
}

static void wov_queue_try_dequeue(struct cros_ec_codec_priv *priv)
{
        size_t period_bytes = snd_pcm_lib_period_bytes(priv->wov_substream);

        while (period_bytes && wov_queue_size(priv) >= period_bytes) {
                wov_queue_dequeue(priv, period_bytes);
                period_bytes = snd_pcm_lib_period_bytes(priv->wov_substream);
        }
}

static void wov_queue_enqueue(struct cros_ec_codec_priv *priv,
                              uint8_t *addr, size_t len, bool iomem)
{
        size_t req;

        while (len) {
                if (wov_queue_full(priv)) {
                        wov_queue_try_dequeue(priv);

                        if (wov_queue_full(priv)) {
                                dev_err(priv->dev, "overrun detected\n");
                                return;
                        }
                }

                if (priv->wov_wp >= priv->wov_rp)
                        req = sizeof(priv->wov_buf) - priv->wov_wp;
                else
                        /* Note: waste 1-byte to differentiate full and empty */
                        req = priv->wov_rp - priv->wov_wp - 1;
                req = min(req, len);

                if (iomem)
                        memcpy_fromio(priv->wov_buf + priv->wov_wp,
                                      (void __force __iomem *)addr, req);
                else
                        memcpy(priv->wov_buf + priv->wov_wp, addr, req);

                priv->wov_wp += req;
                if (priv->wov_wp == sizeof(priv->wov_buf))
                        priv->wov_wp = 0;

                addr += req;
                len -= req;
        }

        wov_queue_try_dequeue(priv);
}

static int wov_read_audio_shm(struct cros_ec_codec_priv *priv)
{
        struct ec_param_ec_codec_wov p;
        struct ec_response_ec_codec_wov_read_audio_shm r;
        int ret;

        p.cmd = EC_CODEC_WOV_READ_AUDIO_SHM;
        ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_WOV,
                                   (uint8_t *)&p, sizeof(p),
                                   (uint8_t *)&r, sizeof(r));
        if (ret) {
                dev_err(priv->dev, "failed to EC_CODEC_WOV_READ_AUDIO_SHM\n");
                return ret;
        }

        if (!r.len)
                dev_dbg(priv->dev, "no data, sleep\n");
        else
                wov_queue_enqueue(priv, priv->wov_audio_shm_p + r.offset, r.len,
                        priv->wov_audio_shm_type == EC_CODEC_SHM_TYPE_EC_RAM);
        return -EAGAIN;
}

static int wov_read_audio(struct cros_ec_codec_priv *priv)
{
        struct ec_param_ec_codec_wov p;
        struct ec_response_ec_codec_wov_read_audio r;
        int remain = priv->wov_burst_read ? 16000 : 320;
        int ret;

        while (remain >= 0) {
                p.cmd = EC_CODEC_WOV_READ_AUDIO;
                ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_WOV,
                                           (uint8_t *)&p, sizeof(p),
                                           (uint8_t *)&r, sizeof(r));
                if (ret) {
                        dev_err(priv->dev,
                                "failed to EC_CODEC_WOV_READ_AUDIO\n");
                        return ret;
                }

                if (!r.len) {
                        dev_dbg(priv->dev, "no data, sleep\n");
                        priv->wov_burst_read = false;
                        break;
                }

                wov_queue_enqueue(priv, r.buf, r.len, false);
                remain -= r.len;
        }

        return -EAGAIN;
}

static void wov_copy_work(struct work_struct *w)
{
        struct cros_ec_codec_priv *priv =
                container_of(w, struct cros_ec_codec_priv, wov_copy_work.work);
        int ret;

        mutex_lock(&priv->wov_dma_lock);
        if (!priv->wov_substream) {
                dev_warn(priv->dev, "no pcm substream\n");
                goto leave;
        }

        if (ec_codec_capable(priv, EC_CODEC_CAP_WOV_AUDIO_SHM))
                ret = wov_read_audio_shm(priv);
        else
                ret = wov_read_audio(priv);

        if (ret == -EAGAIN)
                schedule_delayed_work(&priv->wov_copy_work,
                                      msecs_to_jiffies(10));
        else if (ret)
                dev_err(priv->dev, "failed to read audio data\n");
leave:
        mutex_unlock(&priv->wov_dma_lock);
}

static int wov_enable_get(struct snd_kcontrol *kcontrol,
                          struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_component *c = snd_kcontrol_chip(kcontrol);
        struct cros_ec_codec_priv *priv = snd_soc_component_get_drvdata(c);

        ucontrol->value.integer.value[0] = priv->wov_enabled;
        return 0;
}

static int wov_enable_put(struct snd_kcontrol *kcontrol,
                          struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_component *c = snd_kcontrol_chip(kcontrol);
        struct cros_ec_codec_priv *priv = snd_soc_component_get_drvdata(c);
        int enabled = ucontrol->value.integer.value[0];
        struct ec_param_ec_codec_wov p;
        int ret;

        if (priv->wov_enabled != enabled) {
                if (enabled)
                        p.cmd = EC_CODEC_WOV_ENABLE;
                else
                        p.cmd = EC_CODEC_WOV_DISABLE;

                ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_WOV,
                                           (uint8_t *)&p, sizeof(p), NULL, 0);
                if (ret) {
                        dev_err(priv->dev, "failed to %s wov\n",
                                str_enable_disable(enabled));
                        return ret;
                }

                priv->wov_enabled = enabled;
        }

        return 0;
}

static int wov_set_lang_shm(struct cros_ec_codec_priv *priv,
                            uint8_t *buf, size_t size, uint8_t *digest)
{
        struct ec_param_ec_codec_wov p;
        struct ec_param_ec_codec_wov_set_lang_shm *pp = &p.set_lang_shm_param;
        int ret;

        if (size > priv->wov_lang_shm_len) {
                dev_err(priv->dev, "no enough SHM size: %d\n",
                        priv->wov_lang_shm_len);
                return -EIO;
        }

        switch (priv->wov_lang_shm_type) {
        case EC_CODEC_SHM_TYPE_EC_RAM:
                memcpy_toio((void __force __iomem *)priv->wov_lang_shm_p,
                            buf, size);
                memset_io((void __force __iomem *)priv->wov_lang_shm_p + size,
                          0, priv->wov_lang_shm_len - size);
                break;
        case EC_CODEC_SHM_TYPE_SYSTEM_RAM:
                memcpy(priv->wov_lang_shm_p, buf, size);
                memset(priv->wov_lang_shm_p + size, 0,
                       priv->wov_lang_shm_len - size);

                /* make sure write to memory before calling host command */
                wmb();
                break;
        }

        p.cmd = EC_CODEC_WOV_SET_LANG_SHM;
        memcpy(pp->hash, digest, SHA256_DIGEST_SIZE);
        pp->total_len = size;
        ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_WOV,
                                   (uint8_t *)&p, sizeof(p), NULL, 0);
        if (ret) {
                dev_err(priv->dev, "failed to EC_CODEC_WOV_SET_LANG_SHM\n");
                return ret;
        }

        return 0;
}

static int wov_set_lang(struct cros_ec_codec_priv *priv,
                        uint8_t *buf, size_t size, uint8_t *digest)
{
        struct ec_param_ec_codec_wov p;
        struct ec_param_ec_codec_wov_set_lang *pp = &p.set_lang_param;
        size_t i, req;
        int ret;

        for (i = 0; i < size; i += req) {
                req = min(size - i, ARRAY_SIZE(pp->buf));

                p.cmd = EC_CODEC_WOV_SET_LANG;
                memcpy(pp->hash, digest, SHA256_DIGEST_SIZE);
                pp->total_len = size;
                pp->offset = i;
                memcpy(pp->buf, buf + i, req);
                pp->len = req;
                ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_WOV,
                                           (uint8_t *)&p, sizeof(p), NULL, 0);
                if (ret) {
                        dev_err(priv->dev, "failed to EC_CODEC_WOV_SET_LANG\n");
                        return ret;
                }
        }

        return 0;
}

static int wov_hotword_model_put(struct snd_kcontrol *kcontrol,
                                 const unsigned int __user *bytes,
                                 unsigned int size)
{
        struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);
        struct ec_param_ec_codec_wov p;
        struct ec_response_ec_codec_wov_get_lang r;
        uint8_t digest[SHA256_DIGEST_SIZE];
        uint8_t *buf;
        int ret;

        /* Skips the TLV header. */
        bytes += 2;
        size -= 8;

        dev_dbg(priv->dev, "%s: size=%d\n", __func__, size);

        buf = memdup_user(bytes, size);
        if (IS_ERR(buf))
                return PTR_ERR(buf);

        sha256(buf, size, digest);
        dev_dbg(priv->dev, "hash=%*phN\n", SHA256_DIGEST_SIZE, digest);

        p.cmd = EC_CODEC_WOV_GET_LANG;
        ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_WOV,
                                   (uint8_t *)&p, sizeof(p),
                                   (uint8_t *)&r, sizeof(r));
        if (ret)
                goto leave;

        if (memcmp(digest, r.hash, SHA256_DIGEST_SIZE) == 0) {
                dev_dbg(priv->dev, "not updated");
                goto leave;
        }

        if (ec_codec_capable(priv, EC_CODEC_CAP_WOV_LANG_SHM))
                ret = wov_set_lang_shm(priv, buf, size, digest);
        else
                ret = wov_set_lang(priv, buf, size, digest);

leave:
        kfree(buf);
        return ret;
}

static struct snd_kcontrol_new wov_controls[] = {
        SOC_SINGLE_BOOL_EXT("Wake-on-Voice Switch", 0,
                            wov_enable_get, wov_enable_put),
        SND_SOC_BYTES_TLV("Hotword Model", 0x11000, NULL,
                          wov_hotword_model_put),
};

static struct snd_soc_dai_driver wov_dai_driver = {
        .name = "Wake on Voice",
        .capture = {
                .stream_name = "WoV Capture",
                .channels_min = 1,
                .channels_max = 1,
                .rates = SNDRV_PCM_RATE_16000,
                .formats = SNDRV_PCM_FMTBIT_S16_LE,
        },
};

static int wov_host_event(struct notifier_block *nb,
                          unsigned long queued_during_suspend, void *notify)
{
        struct cros_ec_codec_priv *priv =
                container_of(nb, struct cros_ec_codec_priv, wov_notifier);
        u32 host_event;

        dev_dbg(priv->dev, "%s\n", __func__);

        host_event = cros_ec_get_host_event(priv->ec_device);
        if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_WOV)) {
                schedule_delayed_work(&priv->wov_copy_work, 0);
                return NOTIFY_OK;
        } else {
                return NOTIFY_DONE;
        }
}

static int wov_probe(struct snd_soc_component *component)
{
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);
        int ret;

        mutex_init(&priv->wov_dma_lock);
        INIT_DELAYED_WORK(&priv->wov_copy_work, wov_copy_work);

        priv->wov_notifier.notifier_call = wov_host_event;
        ret = blocking_notifier_chain_register(
                        &priv->ec_device->event_notifier, &priv->wov_notifier);
        if (ret)
                return ret;

        if (ec_codec_capable(priv, EC_CODEC_CAP_WOV_LANG_SHM)) {
                priv->wov_lang_shm_p = wov_map_shm(priv,
                                EC_CODEC_SHM_ID_WOV_LANG,
                                &priv->wov_lang_shm_len,
                                &priv->wov_lang_shm_type);
                if (!priv->wov_lang_shm_p)
                        return -EFAULT;
        }

        if (ec_codec_capable(priv, EC_CODEC_CAP_WOV_AUDIO_SHM)) {
                priv->wov_audio_shm_p = wov_map_shm(priv,
                                EC_CODEC_SHM_ID_WOV_AUDIO,
                                &priv->wov_audio_shm_len,
                                &priv->wov_audio_shm_type);
                if (!priv->wov_audio_shm_p)
                        return -EFAULT;
        }

        return dmic_probe(component);
}

static void wov_remove(struct snd_soc_component *component)
{
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);

        blocking_notifier_chain_unregister(
                        &priv->ec_device->event_notifier, &priv->wov_notifier);
}

static int wov_pcm_open(struct snd_soc_component *component,
                        struct snd_pcm_substream *substream)
{
        static const struct snd_pcm_hardware hw_param = {
                .info = SNDRV_PCM_INFO_MMAP |
                        SNDRV_PCM_INFO_INTERLEAVED |
                        SNDRV_PCM_INFO_MMAP_VALID,
                .formats = SNDRV_PCM_FMTBIT_S16_LE,
                .rates = SNDRV_PCM_RATE_16000,
                .channels_min = 1,
                .channels_max = 1,
                .period_bytes_min = PAGE_SIZE,
                .period_bytes_max = 0x20000 / 8,
                .periods_min = 8,
                .periods_max = 8,
                .buffer_bytes_max = 0x20000,
        };

        return snd_soc_set_runtime_hwparams(substream, &hw_param);
}

static int wov_pcm_hw_params(struct snd_soc_component *component,
                             struct snd_pcm_substream *substream,
                             struct snd_pcm_hw_params *hw_params)
{
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);

        mutex_lock(&priv->wov_dma_lock);
        priv->wov_substream = substream;
        priv->wov_rp = priv->wov_wp = 0;
        priv->wov_dma_offset = 0;
        priv->wov_burst_read = true;
        mutex_unlock(&priv->wov_dma_lock);

        return 0;
}

static int wov_pcm_hw_free(struct snd_soc_component *component,
                           struct snd_pcm_substream *substream)
{
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);

        mutex_lock(&priv->wov_dma_lock);
        wov_queue_dequeue(priv, wov_queue_size(priv));
        priv->wov_substream = NULL;
        mutex_unlock(&priv->wov_dma_lock);

        cancel_delayed_work_sync(&priv->wov_copy_work);

        return 0;
}

static snd_pcm_uframes_t wov_pcm_pointer(struct snd_soc_component *component,
                                         struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct cros_ec_codec_priv *priv =
                snd_soc_component_get_drvdata(component);

        return bytes_to_frames(runtime, priv->wov_dma_offset);
}

static int wov_pcm_new(struct snd_soc_component *component,
                       struct snd_soc_pcm_runtime *rtd)
{
        snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_VMALLOC,
                                       NULL, 0, 0);
        return 0;
}

static const struct snd_soc_component_driver wov_component_driver = {
        .probe          = wov_probe,
        .remove         = wov_remove,
        .controls       = wov_controls,
        .num_controls   = ARRAY_SIZE(wov_controls),
        .open           = wov_pcm_open,
        .hw_params      = wov_pcm_hw_params,
        .hw_free        = wov_pcm_hw_free,
        .pointer        = wov_pcm_pointer,
        .pcm_construct  = wov_pcm_new,
};

static int cros_ec_codec_platform_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct cros_ec_device *ec_device = dev_get_drvdata(pdev->dev.parent);
        struct cros_ec_codec_priv *priv;
        struct ec_param_ec_codec p;
        struct ec_response_ec_codec_get_capabilities r;
        int ret;
#ifdef CONFIG_OF
        struct resource res;
        u64 ec_shm_size;
        const __be32 *regaddr_p;
#endif

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

#ifdef CONFIG_OF
        regaddr_p = of_get_address(dev->of_node, 0, &ec_shm_size, NULL);
        if (regaddr_p) {
                priv->ec_shm_addr = of_read_number(regaddr_p, 2);
                priv->ec_shm_len = ec_shm_size;

                dev_dbg(dev, "ec_shm_addr=%#llx len=%#x\n",
                        priv->ec_shm_addr, priv->ec_shm_len);
        }

        ret = of_reserved_mem_region_to_resource(dev->of_node, 0, &res);
        if (!ret) {
                priv->ap_shm_phys_addr = res.start;
                priv->ap_shm_len = resource_size(&res);
                priv->ap_shm_addr =
                        (uint64_t)(uintptr_t)devm_ioremap_wc(
                                dev, priv->ap_shm_phys_addr,
                                priv->ap_shm_len);
                priv->ap_shm_last_alloc = priv->ap_shm_phys_addr;

                dev_dbg(dev, "ap_shm_phys_addr=%#llx len=%#x\n",
                        priv->ap_shm_phys_addr, priv->ap_shm_len);
        }
#endif

        priv->dev = dev;
        priv->ec_device = ec_device;
        atomic_set(&priv->dmic_probed, 0);

        p.cmd = EC_CODEC_GET_CAPABILITIES;
        ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC,
                                   (uint8_t *)&p, sizeof(p),
                                   (uint8_t *)&r, sizeof(r));
        if (ret) {
                dev_err(dev, "failed to EC_CODEC_GET_CAPABILITIES\n");
                return ret;
        }
        priv->ec_capabilities = r.capabilities;

        /* Reset EC codec i2s rx. */
        p.cmd = EC_CODEC_I2S_RX_RESET;
        ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_I2S_RX,
                                   (uint8_t *)&p, sizeof(p), NULL, 0);
        if (ret == -ENOPROTOOPT) {
                dev_info(dev,
                         "Missing reset command. Please update EC firmware.\n");
        } else if (ret) {
                dev_err(dev, "failed to EC_CODEC_I2S_RESET: %d\n", ret);
                return ret;
        }

        platform_set_drvdata(pdev, priv);

        ret = devm_snd_soc_register_component(dev, &i2s_rx_component_driver,
                                              &i2s_rx_dai_driver, 1);
        if (ret)
                return ret;

        return devm_snd_soc_register_component(dev, &wov_component_driver,
                                               &wov_dai_driver, 1);
}

#ifdef CONFIG_OF
static const struct of_device_id cros_ec_codec_of_match[] = {
        { .compatible = "google,cros-ec-codec" },
        {},
};
MODULE_DEVICE_TABLE(of, cros_ec_codec_of_match);
#endif

#ifdef CONFIG_ACPI
static const struct acpi_device_id cros_ec_codec_acpi_id[] = {
        { "GOOG0013", 0 },
        { }
};
MODULE_DEVICE_TABLE(acpi, cros_ec_codec_acpi_id);
#endif

static struct platform_driver cros_ec_codec_platform_driver = {
        .driver = {
                .name = "cros-ec-codec",
                .of_match_table = of_match_ptr(cros_ec_codec_of_match),
                .acpi_match_table = ACPI_PTR(cros_ec_codec_acpi_id),
        },
        .probe = cros_ec_codec_platform_probe,
};

module_platform_driver(cros_ec_codec_platform_driver);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("ChromeOS EC codec driver");
MODULE_AUTHOR("Cheng-Yi Chiang <cychiang@chromium.org>");
MODULE_ALIAS("platform:cros-ec-codec");