/*

 * Virtio Audio Device

 *

 * Copyright 2009 CodeSourcery

 *

 * 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 "virtio-audio.h"

//#define DEBUG_VIRTIO_AUDIO

#ifdef DEBUG_VIRTIO_AUDIO

#define DPRINTF(fmt, args...) \

do { printf("virtio-audio: " fmt , ##args); } while (0)

#define BADF(fmt, args...) \

do { fprintf(stderr, "virtio-audio: error: " fmt , ##args); exit(1);} while (0)

#else

#define DPRINTF(fmt, args...) do {} while(0)

#define BADF(fmt, args...) \

do { fprintf(stderr, "virtio-audio: error: " fmt , ##args);} while (0)

#endif

#define NUM_STREAMS 2

#define VIRT_CONTROL_QUEUE_SIZE 0x40

#define VIRT_DATA_QUEUE_SIZE 0x80

typedef struct {

    struct VirtIOAudio *dev;

    VirtQueue *data_vq;

    struct audsettings fmt;

    SWVoiceOut *out_voice;

    SWVoiceIn *in_voice;

    VirtQueueElement elem;

    int data_left;

    int data_offset;

    int has_buffer;

} VirtIOAudioStream;

typedef struct VirtIOAudio

{

    VirtIODevice vdev;

    QEMUSoundCard card;

    VirtQueue *cmd_vq;

    VirtIOAudioStream stream[NUM_STREAMS];

} VirtIOAudio;

static VirtIOAudio *to_virtio_audio(VirtIODevice *vdev)

{

    return (VirtIOAudio *)vdev;

}

static void virtio_audio_get_config(VirtIODevice *vdev, uint8_t *config)

{

    struct virtio_audio_cfg audio_cfg;

    audio_cfg.num_streams = NUM_STREAMS;

    memcpy(config, &audio_cfg, sizeof(audio_cfg));

}

static uint32_t virtio_audio_get_features(VirtIODevice *vdev)

{

    uint32_t features = 0;

    return features;

}

static void virtio_audio_set_features(VirtIODevice *vdev, uint32_t features)

{

}

static int virtio_audio_fill(VirtIOAudioStream *stream,

                             int offset, int total_len)

{

    uint8_t *p;

    int to_write;

    int written;

    int size;

    int n;

    struct iovec *iov;

    int iov_len;

    if (stream->in_voice) {

        iov_len = stream->elem.in_num;

        iov = stream->elem.in_sg;

    } else if (stream->out_voice) {

        iov_len = stream->elem.out_num;

        iov = stream->elem.out_sg;

    } else

    {

        DPRINTF("No voice selected skipping block\n");

        return 0;

    }

    written = 0;

    for (n = 0; total_len > 0 && n < iov_len; n++) {

        p = iov[n].iov_base;

        to_write = iov[n].iov_len;

        if (offset) {

            if (offset >= to_write) {

                offset -= to_write;

                continue;

            }

            p += offset;

            to_write -= offset;

            offset = 0;

        }

        if (to_write > total_len)

            to_write = total_len;

        while (to_write) {

            if (stream->in_voice) {

                size = AUD_read(stream->in_voice, p, to_write);

            } else if (stream->out_voice) {

                size = AUD_write(stream->out_voice, p, to_write);

            } else {

                size = 0;

            }

            DPRINTF("Copied %d/%d\n", size, to_write);

            if (size == 0) {

                total_len = 0;

                break;

            }

            to_write -= size;

            total_len -= size;

            written += size;

        }

    }

    return written;

}

static void virtio_audio_callback(void *opaque, int avail)

{

    VirtIOAudioStream *stream = opaque;

    int n;

    DPRINTF("Callback (%d)\n", avail);

    if ((!stream->in_voice)&&(!stream->out_voice))

    {

        DPRINTF("Skipping callback as no voice is selected!\n");

    }

    while (avail) {

        while (stream->data_left == 0) {

            if (stream->has_buffer) {

                virtqueue_push(stream->data_vq, &stream->elem, stream->data_offset);

                virtio_notify(&stream->dev->vdev, stream->data_vq);

                stream->has_buffer = 0;

            }

            if (!virtqueue_pop(stream->data_vq, &stream->elem)) {

                /* Buffer underrun.  */

                stream->has_buffer = 0;

                DPRINTF("Underrun\n");

                break;

            }

            stream->data_offset = 0;

            stream->data_left = 0;

            stream->has_buffer = 1;

            if (stream->in_voice) {

                for (n = 0; n < stream->elem.in_num; n++)

                    stream->data_left += stream->elem.in_sg[n].iov_len;

            } else if (stream->out_voice) {

                for (n = 0; n < stream->elem.out_num; n++)

                    stream->data_left += stream->elem.out_sg[n].iov_len;

            }

        }

        if (stream->data_left == 0)

            break;

        n = virtio_audio_fill(stream, stream->data_offset, avail);

        stream->data_left -= n;

        stream->data_offset += n;

        avail -= n;

        if (!n)

            break;

    }

    if (stream->data_left == 0 && stream->has_buffer) {

        virtqueue_push(stream->data_vq, &stream->elem, stream->data_offset);

        virtio_notify(&stream->dev->vdev, stream->data_vq);

        stream->has_buffer = 0;

    }

}

static void virtio_audio_cmd_result(uint32_t value, VirtQueueElement *elem,

                                    size_t *out_bytes)

{

    size_t offset = *out_bytes;

    int len;

    int n;

    DPRINTF("cmd result %d\n", value);

    for (n = 0; n < elem->in_num; n++) {

        len = elem->in_sg[n].iov_len;

        if (len < offset) {

            offset -= len;

            len = 0;

        } else {

            if (len  - offset < 4) {

                BADF("buffer too short\n");

                return;

            }

            stl_p(elem->in_sg[n].iov_base + offset, value);

            (*out_bytes) += 4;

            return;

        }

    }

    BADF("No space left\n");

}

/* Command queue.  */

static void virtio_audio_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)

{

    VirtIOAudio *s = to_virtio_audio(vdev);

    VirtIOAudioStream *stream;

    VirtQueueElement elem;

    int out_n;

    uint32_t *p;

    int len;

    size_t out_bytes;

    uint32_t value;

    while (virtqueue_pop(s->cmd_vq, &elem)) {

        size_t bytes_transferred = 0;

        for (out_n = 0; out_n < elem.out_num; out_n++) {

            p = (uint32_t *)elem.out_sg[out_n].iov_base;

            len = elem.out_sg[out_n].iov_len;

            while (len > 0) {

                if (len < 12) {

                    BADF("Bad command length\n");

                    break;

                }

                DPRINTF("Command %d %d %d\n",

                        ldl_p(p), ldl_p(p + 1), ldl_p (p + 2));

                value = ldl_p(p + 1);

                if (value >= NUM_STREAMS)

                    break;

                stream = &s->stream[value];

                value = ldl_p(p + 2);

                switch (ldl_p(p)) {

                case VIRTIO_AUDIO_CMD_SET_ENDIAN:

                    stream->fmt.endianness = value;

                    break;

                case VIRTIO_AUDIO_CMD_SET_CHANNELS:

                    stream->fmt.nchannels = value;

                    break;

                case VIRTIO_AUDIO_CMD_SET_FMT:

                    stream->fmt.fmt = value;

                    break;

                case VIRTIO_AUDIO_CMD_SET_FREQ:

                    stream->fmt.freq = value;

                    break;

                case VIRTIO_AUDIO_CMD_INIT:

                    out_bytes = 0;

                    if (value == 1) {

                        if (stream->out_voice) {

                            AUD_close_out(&s->card, stream->out_voice);

                            stream->out_voice = NULL;

                        }

                        stream->in_voice =

                          AUD_open_in(&s->card, stream->in_voice,

                                      "virtio-audio.in",

                                      stream,

                                      virtio_audio_callback,

                                      &stream->fmt);

                        virtio_audio_cmd_result(0, &elem, &out_bytes);

                    } else if (value == 0) {

                        if (stream->in_voice) {

                            AUD_close_in(&s->card, stream->in_voice);

                            stream->in_voice = NULL;

                        }

                        stream->out_voice =

                          AUD_open_out(&s->card, stream->out_voice,

                                       "virtio-audio.out",

                                       stream,

                                       virtio_audio_callback,

                                       &stream->fmt);

                        value = AUD_get_buffer_size_out(stream->out_voice);

                        virtio_audio_cmd_result(value, &elem, &out_bytes);

                    } else { // let us close all down

                        if (stream->out_voice) {

                            AUD_close_out(&s->card, stream->out_voice);

                            stream->out_voice = NULL;

                        }

                        if (stream->in_voice) {

                            AUD_close_in(&s->card, stream->in_voice);

                            stream->in_voice = NULL;

                        }                        

                    }

                    bytes_transferred += out_bytes;

                    break;

                case VIRTIO_AUDIO_CMD_RUN:

                    if (stream->in_voice) {

                        AUD_set_active_in(stream->in_voice, value);

                    } else if (stream->out_voice) {

                        AUD_set_active_out(stream->out_voice, value);

                    } else

                    {

                        DPRINTF("Cannot execute CMD_RUN as no voice is active\n");

                    }

                    break;

                }

                p += 3;

                len -= 12;

                bytes_transferred += 12;

            }

        }

        virtqueue_push(s->cmd_vq, &elem, bytes_transferred);

        virtio_notify(vdev, s->cmd_vq);		

    }

}

static void virtio_audio_handle_data(VirtIODevice *vdev, VirtQueue *vq)

{

}

static void virtio_audio_save(QEMUFile *f, void *opaque)

{

    VirtIOAudio *s = opaque;

    VirtIOAudioStream *stream;

    int i;

    int mode;

    virtio_save(&s->vdev, f);

    for (i = 0; i < NUM_STREAMS; i++) {

        stream = &s->stream[i];

        if (stream->in_voice) {

            mode = 2;

            if (AUD_is_active_in(stream->in_voice))

                mode |= 1;

        } else if (stream->out_voice) {

            mode = 4;

            if (AUD_is_active_out(stream->out_voice))

                mode |= 1;

        } else {

            mode = 0;

        }

        qemu_put_byte(f, mode);

        qemu_put_byte(f, stream->fmt.endianness);

        qemu_put_be16(f, stream->fmt.nchannels);

        qemu_put_be32(f, stream->fmt.fmt);

        qemu_put_be32(f, stream->fmt.freq);

    }

}

static int virtio_audio_load(QEMUFile *f, void *opaque, int version_id)

{

    VirtIOAudio *s = opaque;

    VirtIOAudioStream *stream;

    int i;

    int mode;

    if (version_id != 1)

        return -EINVAL;

    /* FIXME: Do bad things happen if there is a transfer in progress?  */

    virtio_load(&s->vdev, f);

    for (i = 0; i < NUM_STREAMS; i++) {

        stream = &s->stream[i];

        stream->has_buffer = 0;

        stream->data_left = 0;

        if (stream->in_voice) {

            AUD_close_in(&s->card, stream->in_voice);

            stream->in_voice = NULL;

        }

        if (stream->out_voice) {

            AUD_close_out(&s->card, stream->out_voice);

            stream->out_voice = NULL;

        }

        mode = qemu_get_byte(f);

        stream->fmt.endianness = qemu_get_byte(f);

        stream->fmt.nchannels = qemu_get_be16(f);

        stream->fmt.fmt = qemu_get_be32(f);

        stream->fmt.freq = qemu_get_be32(f);

        if (mode & 2) {

            stream->in_voice = AUD_open_in(&s->card, stream->in_voice,

                                           "virtio-audio.in",

                                           stream,

                                           virtio_audio_callback,

                                           &stream->fmt);

            AUD_set_active_in(stream->in_voice, mode & 1);

        } else if (mode & 4) {

            stream->out_voice = AUD_open_out(&s->card, stream->out_voice,

                                             "virtio-audio.out",

                                             stream,

                                             virtio_audio_callback,

                                             &stream->fmt);

            AUD_set_active_out(stream->out_voice, mode & 1);

        }

    }

    return 0;

}

void virtio_audio_init(VirtIOBindFn bind, void *bind_arg, AudioState *audio)

{

    VirtIOAudio *s;

    int i;

    s = (VirtIOAudio *)bind(bind_arg, "virtio-audio", 0, VIRTIO_ID_AUDIO,

                            sizeof(struct virtio_audio_cfg),

                            sizeof(VirtIOAudio));

    if (!s)

        return;

    s->vdev.get_config = virtio_audio_get_config;

    s->vdev.get_features = virtio_audio_get_features;

    s->vdev.set_features = virtio_audio_set_features;

    s->cmd_vq = virtio_add_queue(&s->vdev, VIRT_CONTROL_QUEUE_SIZE, virtio_audio_handle_cmd);

    for (i = 0; i < NUM_STREAMS; i++) {

        s->stream[i].data_vq = virtio_add_queue(&s->vdev, VIRT_DATA_QUEUE_SIZE,

                                                virtio_audio_handle_data);

        s->stream[i].dev = s;

    }

    AUD_register_card(audio, "virtio-audio", &s->card);

    register_savevm("virtio-audio", -1, 1,

                    virtio_audio_save, virtio_audio_load, s);

}