stream.c

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/*
 *   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.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */


#include <linux/init.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/usb/audio.h>
#include <linux/usb/audio-v2.h>

#include <sound/core.h>
#include <sound/pcm.h>

#include "usbaudio.h"
#include "card.h"
#include "proc.h"
#include "quirks.h"
#include "endpoint.h"
#include "pcm.h"
#include "helper.h"
#include "format.h"
#include "clock.h"
#include "stream.h"

/*
 * free a substream
 */
static void free_substream(struct snd_usb_substream *subs)
{
    struct list_head *p, *n;

    if (!subs->num_formats)
        return; /* not initialized */
    list_for_each_safe(p, n, &subs->fmt_list) {
        struct audioformat *fp = list_entry(p, struct audioformat, list);
        kfree(fp->rate_table);
        kfree(fp);
    }
    kfree(subs->rate_list.list);
}


/*
 * free a usb stream instance
 */
static void snd_usb_audio_stream_free(struct snd_usb_stream *stream)
{
    free_substream(&stream->substream[0]);
    free_substream(&stream->substream[1]);
    list_del(&stream->list);
    kfree(stream);
}

static void snd_usb_audio_pcm_free(struct snd_pcm *pcm)
{
    struct snd_usb_stream *stream = pcm->private_data;
    if (stream) {
        stream->pcm = NULL;
        snd_usb_audio_stream_free(stream);
    }
}

/*
 * initialize the substream instance.
 */

static void snd_usb_init_substream(struct snd_usb_stream *as,
                   int stream,
                   struct audioformat *fp)
{
    struct snd_usb_substream *subs = &as->substream[stream];

    INIT_LIST_HEAD(&subs->fmt_list);
    spin_lock_init(&subs->lock);

    subs->stream = as;
    subs->direction = stream;
    subs->dev = as->chip->dev;
    subs->txfr_quirk = as->chip->txfr_quirk;
    subs->speed = snd_usb_get_speed(subs->dev);

    snd_usb_set_pcm_ops(as->pcm, stream);

    list_add_tail(&fp->list, &subs->fmt_list);
    subs->formats |= fp->formats;
    subs->num_formats++;
    subs->fmt_type = fp->fmt_type;
    subs->ep_num = fp->endpoint;
}

/*
 * add this endpoint to the chip instance.
 * if a stream with the same endpoint already exists, append to it.
 * if not, create a new pcm stream.
 */
int snd_usb_add_audio_stream(struct snd_usb_audio *chip,
                 int stream,
                 struct audioformat *fp)
{
    struct list_head *p;
    struct snd_usb_stream *as;
    struct snd_usb_substream *subs;
    struct snd_pcm *pcm;
    int err;

    list_for_each(p, &chip->pcm_list) {
        as = list_entry(p, struct snd_usb_stream, list);
        if (as->fmt_type != fp->fmt_type)
            continue;
        subs = &as->substream[stream];
        if (subs->ep_num == fp->endpoint) {
            list_add_tail(&fp->list, &subs->fmt_list);
            subs->num_formats++;
            subs->formats |= fp->formats;
            return 0;
        }
    }
    /* look for an empty stream */
    list_for_each(p, &chip->pcm_list) {
        as = list_entry(p, struct snd_usb_stream, list);
        if (as->fmt_type != fp->fmt_type)
            continue;
        subs = &as->substream[stream];
        if (subs->ep_num)
            continue;
        err = snd_pcm_new_stream(as->pcm, stream, 1);
        if (err < 0)
            return err;
        snd_usb_init_substream(as, stream, fp);
        return 0;
    }

    /* create a new pcm */
    as = kzalloc(sizeof(*as), GFP_KERNEL);
    if (!as)
        return -ENOMEM;
    as->pcm_index = chip->pcm_devs;
    as->chip = chip;
    as->fmt_type = fp->fmt_type;
    err = snd_pcm_new(chip->card, "USB Audio", chip->pcm_devs,
              stream == SNDRV_PCM_STREAM_PLAYBACK ? 1 : 0,
              stream == SNDRV_PCM_STREAM_PLAYBACK ? 0 : 1,
              &pcm);
    if (err < 0) {
        kfree(as);
        return err;
    }
    as->pcm = pcm;
    pcm->private_data = as;
    pcm->private_free = snd_usb_audio_pcm_free;
    pcm->info_flags = 0;
    if (chip->pcm_devs > 0)
        sprintf(pcm->name, "USB Audio #%d", chip->pcm_devs);
    else
        strcpy(pcm->name, "USB Audio");

    snd_usb_init_substream(as, stream, fp);

    list_add(&as->list, &chip->pcm_list);
    chip->pcm_devs++;

    snd_usb_proc_pcm_format_add(as);

    return 0;
}

static int parse_uac_endpoint_attributes(struct snd_usb_audio *chip,
                     struct usb_host_interface *alts,
                     int protocol, int iface_no)
{
    /* parsed with a v1 header here. that's ok as we only look at the
     * header first which is the same for both versions */
    struct uac_iso_endpoint_descriptor *csep;
    struct usb_interface_descriptor *altsd = get_iface_desc(alts);
    int attributes = 0;

    csep = snd_usb_find_desc(alts->endpoint[0].extra, alts->endpoint[0].extralen, NULL, USB_DT_CS_ENDPOINT);

    /* Creamware Noah has this descriptor after the 2nd endpoint */
    if (!csep && altsd->bNumEndpoints >= 2)
        csep = snd_usb_find_desc(alts->endpoint[1].extra, alts->endpoint[1].extralen, NULL, USB_DT_CS_ENDPOINT);

    if (!csep || csep->bLength < 7 ||
        csep->bDescriptorSubtype != UAC_EP_GENERAL) {
        snd_printk(KERN_WARNING "%d:%u:%d : no or invalid"
               " class specific endpoint descriptor\n",
               chip->dev->devnum, iface_no,
               altsd->bAlternateSetting);
        return 0;
    }

    if (protocol == UAC_VERSION_1) {
        attributes = csep->bmAttributes;
    } else {
        struct uac2_iso_endpoint_descriptor *csep2 =
            (struct uac2_iso_endpoint_descriptor *) csep;

        attributes = csep->bmAttributes & UAC_EP_CS_ATTR_FILL_MAX;

        /* emulate the endpoint attributes of a v1 device */
        if (csep2->bmControls & UAC2_CONTROL_PITCH)
            attributes |= UAC_EP_CS_ATTR_PITCH_CONTROL;
    }

    return attributes;
}

static struct uac2_input_terminal_descriptor *
    snd_usb_find_input_terminal_descriptor(struct usb_host_interface *ctrl_iface,
                           int terminal_id)
{
    struct uac2_input_terminal_descriptor *term = NULL;

    while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
                           ctrl_iface->extralen,
                           term, UAC_INPUT_TERMINAL))) {
        if (term->bTerminalID == terminal_id)
            return term;
    }

    return NULL;
}

static struct uac2_output_terminal_descriptor *
    snd_usb_find_output_terminal_descriptor(struct usb_host_interface *ctrl_iface,
                        int terminal_id)
{
    struct uac2_output_terminal_descriptor *term = NULL;

    while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
                           ctrl_iface->extralen,
                           term, UAC_OUTPUT_TERMINAL))) {
        if (term->bTerminalID == terminal_id)
            return term;
    }

    return NULL;
}

int snd_usb_parse_audio_interface(struct snd_usb_audio *chip, int iface_no)
{
    struct usb_device *dev;
    struct usb_interface *iface;
    struct usb_host_interface *alts;
    struct usb_interface_descriptor *altsd;
    int i, altno, err, stream;
    int format = 0, num_channels = 0;
    struct audioformat *fp = NULL;
    int num, protocol, clock = 0;
    struct uac_format_type_i_continuous_descriptor *fmt;

    dev = chip->dev;

    /* parse the interface's altsettings */
    iface = usb_ifnum_to_if(dev, iface_no);

    num = iface->num_altsetting;

    /*
     * Dallas DS4201 workaround: It presents 5 altsettings, but the last
     * one misses syncpipe, and does not produce any sound.
     */
    if (chip->usb_id == USB_ID(0x04fa, 0x4201))
        num = 4;

    for (i = 0; i < num; i++) {
        alts = &iface->altsetting[i];
        altsd = get_iface_desc(alts);
        protocol = altsd->bInterfaceProtocol;
        /* skip invalid one */
        if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
             altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
            (altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING &&
             altsd->bInterfaceSubClass != USB_SUBCLASS_VENDOR_SPEC) ||
            altsd->bNumEndpoints < 1 ||
            le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) == 0)
            continue;
        /* must be isochronous */
        if ((get_endpoint(alts, 0)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) !=
            USB_ENDPOINT_XFER_ISOC)
            continue;
        /* check direction */
        stream = (get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN) ?
            SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
        altno = altsd->bAlternateSetting;

        if (snd_usb_apply_interface_quirk(chip, iface_no, altno))
            continue;

        /* get audio formats */
        switch (protocol) {
        default:
            snd_printdd(KERN_WARNING "%d:%u:%d: unknown interface protocol %#02x, assuming v1\n",
                    dev->devnum, iface_no, altno, protocol);
            protocol = UAC_VERSION_1;
            /* fall through */

        case UAC_VERSION_1: {
            struct uac1_as_header_descriptor *as =
                snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);

            if (!as) {
                snd_printk(KERN_ERR "%d:%u:%d : UAC_AS_GENERAL descriptor not found\n",
                       dev->devnum, iface_no, altno);
                continue;
            }

            if (as->bLength < sizeof(*as)) {
                snd_printk(KERN_ERR "%d:%u:%d : invalid UAC_AS_GENERAL desc\n",
                       dev->devnum, iface_no, altno);
                continue;
            }

            format = le16_to_cpu(as->wFormatTag); /* remember the format value */
            break;
        }

        case UAC_VERSION_2: {
            struct uac2_input_terminal_descriptor *input_term;
            struct uac2_output_terminal_descriptor *output_term;
            struct uac2_as_header_descriptor *as =
                snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);

            if (!as) {
                snd_printk(KERN_ERR "%d:%u:%d : UAC_AS_GENERAL descriptor not found\n",
                       dev->devnum, iface_no, altno);
                continue;
            }

            if (as->bLength < sizeof(*as)) {
                snd_printk(KERN_ERR "%d:%u:%d : invalid UAC_AS_GENERAL desc\n",
                       dev->devnum, iface_no, altno);
                continue;
            }

            num_channels = as->bNrChannels;
            format = le32_to_cpu(as->bmFormats);

            /* lookup the terminal associated to this interface
             * to extract the clock */
            input_term = snd_usb_find_input_terminal_descriptor(chip->ctrl_intf,
                                        as->bTerminalLink);
            if (input_term) {
                clock = input_term->bCSourceID;
                break;
            }

            output_term = snd_usb_find_output_terminal_descriptor(chip->ctrl_intf,
                                          as->bTerminalLink);
            if (output_term) {
                clock = output_term->bCSourceID;
                break;
            }

            snd_printk(KERN_ERR "%d:%u:%d : bogus bTerminalLink %d\n",
                   dev->devnum, iface_no, altno, as->bTerminalLink);
            continue;
        }
        }

        /* get format type */
        fmt = snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_FORMAT_TYPE);
        if (!fmt) {
            snd_printk(KERN_ERR "%d:%u:%d : no UAC_FORMAT_TYPE desc\n",
                   dev->devnum, iface_no, altno);
            continue;
        }
        if (((protocol == UAC_VERSION_1) && (fmt->bLength < 8)) ||
            ((protocol == UAC_VERSION_2) && (fmt->bLength < 6))) {
            snd_printk(KERN_ERR "%d:%u:%d : invalid UAC_FORMAT_TYPE desc\n",
                   dev->devnum, iface_no, altno);
            continue;
        }

        /*
         * Blue Microphones workaround: The last altsetting is identical
         * with the previous one, except for a larger packet size, but
         * is actually a mislabeled two-channel setting; ignore it.
         */
        if (fmt->bNrChannels == 1 &&
            fmt->bSubframeSize == 2 &&
            altno == 2 && num == 3 &&
            fp && fp->altsetting == 1 && fp->channels == 1 &&
            fp->formats == SNDRV_PCM_FMTBIT_S16_LE &&
            protocol == UAC_VERSION_1 &&
            le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) ==
                            fp->maxpacksize * 2)
            continue;

        fp = kzalloc(sizeof(*fp), GFP_KERNEL);
        if (! fp) {
            snd_printk(KERN_ERR "cannot malloc\n");
            return -ENOMEM;
        }

        fp->iface = iface_no;
        fp->altsetting = altno;
        fp->altset_idx = i;
        fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
        fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
        fp->datainterval = snd_usb_parse_datainterval(chip, alts);
        fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
        /* num_channels is only set for v2 interfaces */
        fp->channels = num_channels;
        if (snd_usb_get_speed(dev) == USB_SPEED_HIGH)
            fp->maxpacksize = (((fp->maxpacksize >> 11) & 3) + 1)
                    * (fp->maxpacksize & 0x7ff);
        fp->attributes = parse_uac_endpoint_attributes(chip, alts, protocol, iface_no);
        fp->clock = clock;

        /* some quirks for attributes here */

        switch (chip->usb_id) {
        case USB_ID(0x0a92, 0x0053): /* AudioTrak Optoplay */
            /* Optoplay sets the sample rate attribute although
             * it seems not supporting it in fact.
             */
            fp->attributes &= ~UAC_EP_CS_ATTR_SAMPLE_RATE;
            break;
        case USB_ID(0x041e, 0x3020): /* Creative SB Audigy 2 NX */
        case USB_ID(0x0763, 0x2003): /* M-Audio Audiophile USB */
            /* doesn't set the sample rate attribute, but supports it */
            fp->attributes |= UAC_EP_CS_ATTR_SAMPLE_RATE;
            break;
        case USB_ID(0x0763, 0x2001):  /* M-Audio Quattro USB */
        case USB_ID(0x0763, 0x2012):  /* M-Audio Fast Track Pro USB */
        case USB_ID(0x047f, 0x0ca1): /* plantronics headset */
        case USB_ID(0x077d, 0x07af): /* Griffin iMic (note that there is
                        an older model 77d:223) */
        /*
         * plantronics headset and Griffin iMic have set adaptive-in
         * although it's really not...
         */
            fp->ep_attr &= ~USB_ENDPOINT_SYNCTYPE;
            if (stream == SNDRV_PCM_STREAM_PLAYBACK)
                fp->ep_attr |= USB_ENDPOINT_SYNC_ADAPTIVE;
            else
                fp->ep_attr |= USB_ENDPOINT_SYNC_SYNC;
            break;
        }

        /* ok, let's parse further... */
        if (snd_usb_parse_audio_format(chip, fp, format, fmt, stream, alts) < 0) {
            kfree(fp->rate_table);
            kfree(fp);
            fp = NULL;
            continue;
        }

        snd_printdd(KERN_INFO "%d:%u:%d: add audio endpoint %#x\n", dev->devnum, iface_no, altno, fp->endpoint);
        err = snd_usb_add_audio_stream(chip, stream, fp);
        if (err < 0) {
            kfree(fp->rate_table);
            kfree(fp);
            return err;
        }
        /* try to set the interface... */
        usb_set_interface(chip->dev, iface_no, altno);
        snd_usb_init_pitch(chip, iface_no, alts, fp);
        snd_usb_init_sample_rate(chip, iface_no, alts, fp, fp->rate_max);
    }
    return 0;
}