pcm.c

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/*
 * Line6 Linux USB driver - 0.9.1beta
 *
 * Copyright (C) 2004-2010 Markus Grabner ([email protected])
 *
 *  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, version 2.
 *
 */

#include <linux/slab.h>
#include <sound/core.h>
#include <sound/control.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>

#include "audio.h"
#include "capture.h"
#include "driver.h"
#include "playback.h"
#include "pod.h"

#ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE

static struct snd_line6_pcm *dev2pcm(struct device *dev)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6 *line6 = usb_get_intfdata(interface);
    struct snd_line6_pcm *line6pcm = line6->line6pcm;
    return line6pcm;
}

/*
    "read" request on "impulse_volume" special file.
*/
static ssize_t pcm_get_impulse_volume(struct device *dev,
                      struct device_attribute *attr, char *buf)
{
    return sprintf(buf, "%d\n", dev2pcm(dev)->impulse_volume);
}

/*
    "write" request on "impulse_volume" special file.
*/
static ssize_t pcm_set_impulse_volume(struct device *dev,
                      struct device_attribute *attr,
                      const char *buf, size_t count)
{
    struct snd_line6_pcm *line6pcm = dev2pcm(dev);
    int value;
    int rv;

    rv = kstrtoint(buf, 10, &value);
    if (rv < 0)
        return rv;

    line6pcm->impulse_volume = value;

    if (value > 0)
        line6_pcm_acquire(line6pcm, LINE6_BITS_PCM_IMPULSE);
    else
        line6_pcm_release(line6pcm, LINE6_BITS_PCM_IMPULSE);

    return count;
}

/*
    "read" request on "impulse_period" special file.
*/
static ssize_t pcm_get_impulse_period(struct device *dev,
                      struct device_attribute *attr, char *buf)
{
    return sprintf(buf, "%d\n", dev2pcm(dev)->impulse_period);
}

/*
    "write" request on "impulse_period" special file.
*/
static ssize_t pcm_set_impulse_period(struct device *dev,
                      struct device_attribute *attr,
                      const char *buf, size_t count)
{
    dev2pcm(dev)->impulse_period = simple_strtoul(buf, NULL, 10);
    return count;
}

static DEVICE_ATTR(impulse_volume, S_IWUSR | S_IRUGO, pcm_get_impulse_volume,
           pcm_set_impulse_volume);
static DEVICE_ATTR(impulse_period, S_IWUSR | S_IRUGO, pcm_get_impulse_period,
           pcm_set_impulse_period);

#endif

static bool test_flags(unsigned long flags0, unsigned long flags1,
               unsigned long mask)
{
    return ((flags0 & mask) == 0) && ((flags1 & mask) != 0);
}

int line6_pcm_acquire(struct snd_line6_pcm *line6pcm, int channels)
{
    unsigned long flags_old =
        __sync_fetch_and_or(&line6pcm->flags, channels);
    unsigned long flags_new = flags_old | channels;
    unsigned long flags_final = flags_old;
    int err = 0;

    line6pcm->prev_fbuf = NULL;

    if (test_flags(flags_old, flags_new, LINE6_BITS_CAPTURE_BUFFER)) {
        /* We may be invoked multiple times in a row so allocate once only */
        if (!line6pcm->buffer_in) {
            line6pcm->buffer_in =
                kmalloc(LINE6_ISO_BUFFERS * LINE6_ISO_PACKETS *
                    line6pcm->max_packet_size, GFP_KERNEL);

            if (!line6pcm->buffer_in) {
                dev_err(line6pcm->line6->ifcdev,
                    "cannot malloc capture buffer\n");
                err = -ENOMEM;
                goto pcm_acquire_error;
            }

            flags_final |= channels & LINE6_BITS_CAPTURE_BUFFER;
        }
    }

    if (test_flags(flags_old, flags_new, LINE6_BITS_CAPTURE_STREAM)) {
        /*
           Waiting for completion of active URBs in the stop handler is
           a bug, we therefore report an error if capturing is restarted
           too soon.
         */
        if (line6pcm->active_urb_in | line6pcm->unlink_urb_in) {
            dev_err(line6pcm->line6->ifcdev, "Device not yet ready\n");
            return -EBUSY;
        }

        line6pcm->count_in = 0;
        line6pcm->prev_fsize = 0;
        err = line6_submit_audio_in_all_urbs(line6pcm);

        if (err < 0)
            goto pcm_acquire_error;

        flags_final |= channels & LINE6_BITS_CAPTURE_STREAM;
    }

    if (test_flags(flags_old, flags_new, LINE6_BITS_PLAYBACK_BUFFER)) {
        /* We may be invoked multiple times in a row so allocate once only */
        if (!line6pcm->buffer_out) {
            line6pcm->buffer_out =
                kmalloc(LINE6_ISO_BUFFERS * LINE6_ISO_PACKETS *
                    line6pcm->max_packet_size, GFP_KERNEL);

            if (!line6pcm->buffer_out) {
                dev_err(line6pcm->line6->ifcdev,
                    "cannot malloc playback buffer\n");
                err = -ENOMEM;
                goto pcm_acquire_error;
            }

            flags_final |= channels & LINE6_BITS_PLAYBACK_BUFFER;
        }
    }

    if (test_flags(flags_old, flags_new, LINE6_BITS_PLAYBACK_STREAM)) {
        /*
          See comment above regarding PCM restart.
        */
        if (line6pcm->active_urb_out | line6pcm->unlink_urb_out) {
            dev_err(line6pcm->line6->ifcdev, "Device not yet ready\n");
            return -EBUSY;
        }

        line6pcm->count_out = 0;
        err = line6_submit_audio_out_all_urbs(line6pcm);

        if (err < 0)
            goto pcm_acquire_error;

        flags_final |= channels & LINE6_BITS_PLAYBACK_STREAM;
    }

    return 0;

pcm_acquire_error:
    /*
       If not all requested resources/streams could be obtained, release
       those which were successfully obtained (if any).
    */
    line6_pcm_release(line6pcm, flags_final & channels);
    return err;
}

int line6_pcm_release(struct snd_line6_pcm *line6pcm, int channels)
{
    unsigned long flags_old =
        __sync_fetch_and_and(&line6pcm->flags, ~channels);
    unsigned long flags_new = flags_old & ~channels;

    if (test_flags(flags_new, flags_old, LINE6_BITS_CAPTURE_STREAM))
        line6_unlink_audio_in_urbs(line6pcm);

    if (test_flags(flags_new, flags_old, LINE6_BITS_CAPTURE_BUFFER)) {
        line6_wait_clear_audio_in_urbs(line6pcm);
        line6_free_capture_buffer(line6pcm);
    }

    if (test_flags(flags_new, flags_old, LINE6_BITS_PLAYBACK_STREAM))
        line6_unlink_audio_out_urbs(line6pcm);

    if (test_flags(flags_new, flags_old, LINE6_BITS_PLAYBACK_BUFFER)) {
        line6_wait_clear_audio_out_urbs(line6pcm);
        line6_free_playback_buffer(line6pcm);
    }

    return 0;
}

/* trigger callback */
int snd_line6_trigger(struct snd_pcm_substream *substream, int cmd)
{
    struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
    struct snd_pcm_substream *s;
    int err;
    unsigned long flags;

    spin_lock_irqsave(&line6pcm->lock_trigger, flags);
    clear_bit(LINE6_INDEX_PREPARED, &line6pcm->flags);

    snd_pcm_group_for_each_entry(s, substream) {
        switch (s->stream) {
        case SNDRV_PCM_STREAM_PLAYBACK:
            err = snd_line6_playback_trigger(line6pcm, cmd);

            if (err < 0) {
                spin_unlock_irqrestore(&line6pcm->lock_trigger,
                               flags);
                return err;
            }

            break;

        case SNDRV_PCM_STREAM_CAPTURE:
            err = snd_line6_capture_trigger(line6pcm, cmd);

            if (err < 0) {
                spin_unlock_irqrestore(&line6pcm->lock_trigger,
                               flags);
                return err;
            }

            break;

        default:
            dev_err(line6pcm->line6->ifcdev,
                "Unknown stream direction %d\n", s->stream);
        }
    }

    spin_unlock_irqrestore(&line6pcm->lock_trigger, flags);
    return 0;
}

/* control info callback */
static int snd_line6_control_playback_info(struct snd_kcontrol *kcontrol,
                       struct snd_ctl_elem_info *uinfo)
{
    uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
    uinfo->count = 2;
    uinfo->value.integer.min = 0;
    uinfo->value.integer.max = 256;
    return 0;
}

/* control get callback */
static int snd_line6_control_playback_get(struct snd_kcontrol *kcontrol,
                      struct snd_ctl_elem_value *ucontrol)
{
    int i;
    struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);

    for (i = 2; i--;)
        ucontrol->value.integer.value[i] = line6pcm->volume_playback[i];

    return 0;
}

/* control put callback */
static int snd_line6_control_playback_put(struct snd_kcontrol *kcontrol,
                      struct snd_ctl_elem_value *ucontrol)
{
    int i, changed = 0;
    struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);

    for (i = 2; i--;)
        if (line6pcm->volume_playback[i] !=
            ucontrol->value.integer.value[i]) {
            line6pcm->volume_playback[i] =
                ucontrol->value.integer.value[i];
            changed = 1;
        }

    return changed;
}

/* control definition */
static struct snd_kcontrol_new line6_control_playback = {
    .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
    .name = "PCM Playback Volume",
    .index = 0,
    .access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
    .info = snd_line6_control_playback_info,
    .get = snd_line6_control_playback_get,
    .put = snd_line6_control_playback_put
};

/*
    Cleanup the PCM device.
*/
static void line6_cleanup_pcm(struct snd_pcm *pcm)
{
    int i;
    struct snd_line6_pcm *line6pcm = snd_pcm_chip(pcm);

#ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
    device_remove_file(line6pcm->line6->ifcdev, &dev_attr_impulse_volume);
    device_remove_file(line6pcm->line6->ifcdev, &dev_attr_impulse_period);
#endif

    for (i = LINE6_ISO_BUFFERS; i--;) {
        if (line6pcm->urb_audio_out[i]) {
            usb_kill_urb(line6pcm->urb_audio_out[i]);
            usb_free_urb(line6pcm->urb_audio_out[i]);
        }
        if (line6pcm->urb_audio_in[i]) {
            usb_kill_urb(line6pcm->urb_audio_in[i]);
            usb_free_urb(line6pcm->urb_audio_in[i]);
        }
    }
}

/* create a PCM device */
static int snd_line6_new_pcm(struct snd_line6_pcm *line6pcm)
{
    struct snd_pcm *pcm;
    int err;

    err = snd_pcm_new(line6pcm->line6->card,
              (char *)line6pcm->line6->properties->name,
              0, 1, 1, &pcm);
    if (err < 0)
        return err;

    pcm->private_data = line6pcm;
    pcm->private_free = line6_cleanup_pcm;
    line6pcm->pcm = pcm;
    strcpy(pcm->name, line6pcm->line6->properties->name);

    /* set operators */
    snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
            &snd_line6_playback_ops);
    snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_line6_capture_ops);

    /* pre-allocation of buffers */
    snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
                          snd_dma_continuous_data
                          (GFP_KERNEL), 64 * 1024,
                          128 * 1024);

    return 0;
}

/* PCM device destructor */
static int snd_line6_pcm_free(struct snd_device *device)
{
    return 0;
}

/*
    Stop substream if still running.
*/
static void pcm_disconnect_substream(struct snd_pcm_substream *substream)
{
    if (substream->runtime && snd_pcm_running(substream))
        snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED);
}

/*
    Stop PCM stream.
*/
void line6_pcm_disconnect(struct snd_line6_pcm *line6pcm)
{
    pcm_disconnect_substream(get_substream
                 (line6pcm, SNDRV_PCM_STREAM_CAPTURE));
    pcm_disconnect_substream(get_substream
                 (line6pcm, SNDRV_PCM_STREAM_PLAYBACK));
    line6_unlink_wait_clear_audio_out_urbs(line6pcm);
    line6_unlink_wait_clear_audio_in_urbs(line6pcm);
}

/*
    Create and register the PCM device and mixer entries.
    Create URBs for playback and capture.
*/
int line6_init_pcm(struct usb_line6 *line6,
           struct line6_pcm_properties *properties)
{
    static struct snd_device_ops pcm_ops = {
        .dev_free = snd_line6_pcm_free,
    };

    int err;
    int ep_read = 0, ep_write = 0;
    struct snd_line6_pcm *line6pcm;

    if (!(line6->properties->capabilities & LINE6_BIT_PCM))
        return 0;   /* skip PCM initialization and report success */

    /* initialize PCM subsystem based on product id: */
    switch (line6->product) {
    case LINE6_DEVID_BASSPODXT:
    case LINE6_DEVID_BASSPODXTLIVE:
    case LINE6_DEVID_BASSPODXTPRO:
    case LINE6_DEVID_PODXT:
    case LINE6_DEVID_PODXTLIVE:
    case LINE6_DEVID_PODXTPRO:
    case LINE6_DEVID_PODHD300:
        ep_read = 0x82;
        ep_write = 0x01;
        break;

    case LINE6_DEVID_PODHD500:
    case LINE6_DEVID_PODX3:
    case LINE6_DEVID_PODX3LIVE:
        ep_read = 0x86;
        ep_write = 0x02;
        break;

    case LINE6_DEVID_POCKETPOD:
        ep_read = 0x82;
        ep_write = 0x02;
        break;

    case LINE6_DEVID_GUITARPORT:
    case LINE6_DEVID_PODSTUDIO_GX:
    case LINE6_DEVID_PODSTUDIO_UX1:
    case LINE6_DEVID_PODSTUDIO_UX2:
    case LINE6_DEVID_TONEPORT_GX:
    case LINE6_DEVID_TONEPORT_UX1:
    case LINE6_DEVID_TONEPORT_UX2:
        ep_read = 0x82;
        ep_write = 0x01;
        break;

        /* this is for interface_number == 1:
           case LINE6_DEVID_TONEPORT_UX2:
           case LINE6_DEVID_PODSTUDIO_UX2:
           ep_read  = 0x87;
           ep_write = 0x00;
           break;
         */

    default:
        MISSING_CASE;
    }

    line6pcm = kzalloc(sizeof(struct snd_line6_pcm), GFP_KERNEL);

    if (line6pcm == NULL)
        return -ENOMEM;

    line6pcm->volume_playback[0] = line6pcm->volume_playback[1] = 255;
    line6pcm->volume_monitor = 255;
    line6pcm->line6 = line6;
    line6pcm->ep_audio_read = ep_read;
    line6pcm->ep_audio_write = ep_write;

    /* Read and write buffers are sized identically, so choose minimum */
    line6pcm->max_packet_size = min(
            usb_maxpacket(line6->usbdev,
                usb_rcvisocpipe(line6->usbdev, ep_read), 0),
            usb_maxpacket(line6->usbdev,
                usb_sndisocpipe(line6->usbdev, ep_write), 1));

    line6pcm->properties = properties;
    line6->line6pcm = line6pcm;

    /* PCM device: */
    err = snd_device_new(line6->card, SNDRV_DEV_PCM, line6, &pcm_ops);
    if (err < 0)
        return err;

    snd_card_set_dev(line6->card, line6->ifcdev);

    err = snd_line6_new_pcm(line6pcm);
    if (err < 0)
        return err;

    spin_lock_init(&line6pcm->lock_audio_out);
    spin_lock_init(&line6pcm->lock_audio_in);
    spin_lock_init(&line6pcm->lock_trigger);

    err = line6_create_audio_out_urbs(line6pcm);
    if (err < 0)
        return err;

    err = line6_create_audio_in_urbs(line6pcm);
    if (err < 0)
        return err;

    /* mixer: */
    err =
        snd_ctl_add(line6->card,
            snd_ctl_new1(&line6_control_playback, line6pcm));
    if (err < 0)
        return err;

#ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
    /* impulse response test: */
    err = device_create_file(line6->ifcdev, &dev_attr_impulse_volume);
    if (err < 0)
        return err;

    err = device_create_file(line6->ifcdev, &dev_attr_impulse_period);
    if (err < 0)
        return err;

    line6pcm->impulse_period = LINE6_IMPULSE_DEFAULT_PERIOD;
#endif

    return 0;
}

/* prepare pcm callback */
int snd_line6_prepare(struct snd_pcm_substream *substream)
{
    struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);

    switch (substream->stream) {
    case SNDRV_PCM_STREAM_PLAYBACK:
        if ((line6pcm->flags & LINE6_BITS_PLAYBACK_STREAM) == 0)
            line6_unlink_wait_clear_audio_out_urbs(line6pcm);

        break;

    case SNDRV_PCM_STREAM_CAPTURE:
        if ((line6pcm->flags & LINE6_BITS_CAPTURE_STREAM) == 0)
            line6_unlink_wait_clear_audio_in_urbs(line6pcm);

        break;

    default:
        MISSING_CASE;
    }

    if (!test_and_set_bit(LINE6_INDEX_PREPARED, &line6pcm->flags)) {
        line6pcm->count_out = 0;
        line6pcm->pos_out = 0;
        line6pcm->pos_out_done = 0;
        line6pcm->bytes_out = 0;
        line6pcm->count_in = 0;
        line6pcm->pos_in_done = 0;
        line6pcm->bytes_in = 0;
    }

    return 0;
}