pcm.h

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/*
 * Linux driver for TerraTec DMX 6Fire USB
 *
 * Author:  Torsten Schenk <[email protected]>
 * Created: Jan 01, 2011
 * Copyright:   (C) Torsten Schenk
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#ifndef USB6FIRE_PCM_H
#define USB6FIRE_PCM_H

#include <sound/pcm.h>
#include <linux/mutex.h>

#include "common.h"

enum /* settings for pcm */
{
    /* maximum of EP_W_MAX_PACKET_SIZE[] (see firmware.c) */
    PCM_N_URBS = 16, PCM_N_PACKETS_PER_URB = 8, PCM_MAX_PACKET_SIZE = 604
};

struct pcm_urb {
    struct sfire_chip *chip;

    /* BEGIN DO NOT SEPARATE */
    struct urb instance;
    struct usb_iso_packet_descriptor packets[PCM_N_PACKETS_PER_URB];
    /* END DO NOT SEPARATE */
    u8 buffer[PCM_N_PACKETS_PER_URB * PCM_MAX_PACKET_SIZE];

    struct pcm_urb *peer;
};

struct pcm_substream {
    spinlock_t lock;
    struct snd_pcm_substream *instance;

    bool active;

    snd_pcm_uframes_t dma_off; /* current position in alsa dma_area */
    snd_pcm_uframes_t period_off; /* current position in current period */
};

struct pcm_runtime {
    struct sfire_chip *chip;
    struct snd_pcm *instance;

    struct pcm_substream playback;
    struct pcm_substream capture;
    bool panic; /* if set driver won't do anymore pcm on device */

    struct pcm_urb in_urbs[PCM_N_URBS];
    struct pcm_urb out_urbs[PCM_N_URBS];
    int in_packet_size;
    int out_packet_size;
    int in_n_analog; /* number of analog channels soundcard sends */
    int out_n_analog; /* number of analog channels soundcard receives */

    struct mutex stream_mutex;
    u8 stream_state; /* one of STREAM_XXX (pcm.c) */
    u8 rate; /* one of PCM_RATE_XXX */
    wait_queue_head_t stream_wait_queue;
    bool stream_wait_cond;
};

int __devinit usb6fire_pcm_init(struct sfire_chip *chip);
void usb6fire_pcm_abort(struct sfire_chip *chip);
void usb6fire_pcm_destroy(struct sfire_chip *chip);
#endif /* USB6FIRE_PCM_H */