format.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 "quirks.h"
#include "helper.h"
#include "debug.h"
#include "clock.h"
#include "format.h"

/*
 * parse the audio format type I descriptor
 * and returns the corresponding pcm format
 *
 * @dev: usb device
 * @fp: audioformat record
 * @format: the format tag (wFormatTag)
 * @fmt: the format type descriptor
 */
static u64 parse_audio_format_i_type(struct snd_usb_audio *chip,
                     struct audioformat *fp,
                     int format, void *_fmt,
                     int protocol)
{
    int sample_width, sample_bytes;
    u64 pcm_formats;

    switch (protocol) {
    case UAC_VERSION_1:
    default: {
        struct uac_format_type_i_discrete_descriptor *fmt = _fmt;
        sample_width = fmt->bBitResolution;
        sample_bytes = fmt->bSubframeSize;
        format = 1 << format;
        break;
    }

    case UAC_VERSION_2: {
        struct uac_format_type_i_ext_descriptor *fmt = _fmt;
        sample_width = fmt->bBitResolution;
        sample_bytes = fmt->bSubslotSize;
        format <<= 1;
        break;
    }
    }

    pcm_formats = 0;

    if (format == 0 || format == (1 << UAC_FORMAT_TYPE_I_UNDEFINED)) {
        /* some devices don't define this correctly... */
        snd_printdd(KERN_INFO "%d:%u:%d : format type 0 is detected, processed as PCM\n",
                chip->dev->devnum, fp->iface, fp->altsetting);
        format = 1 << UAC_FORMAT_TYPE_I_PCM;
    }
    if (format & (1 << UAC_FORMAT_TYPE_I_PCM)) {
        if (chip->usb_id == USB_ID(0x0582, 0x0016) /* Edirol SD-90 */ &&
            sample_width == 24 && sample_bytes == 2)
            sample_bytes = 3;
        else if (sample_width > sample_bytes * 8) {
            snd_printk(KERN_INFO "%d:%u:%d : sample bitwidth %d in over sample bytes %d\n",
                   chip->dev->devnum, fp->iface, fp->altsetting,
                   sample_width, sample_bytes);
        }
        /* check the format byte size */
        switch (sample_bytes) {
        case 1:
            pcm_formats |= SNDRV_PCM_FMTBIT_S8;
            break;
        case 2:
            if (snd_usb_is_big_endian_format(chip, fp))
                pcm_formats |= SNDRV_PCM_FMTBIT_S16_BE; /* grrr, big endian!! */
            else
                pcm_formats |= SNDRV_PCM_FMTBIT_S16_LE;
            break;
        case 3:
            if (snd_usb_is_big_endian_format(chip, fp))
                pcm_formats |= SNDRV_PCM_FMTBIT_S24_3BE; /* grrr, big endian!! */
            else
                pcm_formats |= SNDRV_PCM_FMTBIT_S24_3LE;
            break;
        case 4:
            pcm_formats |= SNDRV_PCM_FMTBIT_S32_LE;
            break;
        default:
            snd_printk(KERN_INFO "%d:%u:%d : unsupported sample bitwidth %d in %d bytes\n",
                   chip->dev->devnum, fp->iface, fp->altsetting,
                   sample_width, sample_bytes);
            break;
        }
    }
    if (format & (1 << UAC_FORMAT_TYPE_I_PCM8)) {
        /* Dallas DS4201 workaround: it advertises U8 format, but really
           supports S8. */
        if (chip->usb_id == USB_ID(0x04fa, 0x4201))
            pcm_formats |= SNDRV_PCM_FMTBIT_S8;
        else
            pcm_formats |= SNDRV_PCM_FMTBIT_U8;
    }
    if (format & (1 << UAC_FORMAT_TYPE_I_IEEE_FLOAT)) {
        pcm_formats |= SNDRV_PCM_FMTBIT_FLOAT_LE;
    }
    if (format & (1 << UAC_FORMAT_TYPE_I_ALAW)) {
        pcm_formats |= SNDRV_PCM_FMTBIT_A_LAW;
    }
    if (format & (1 << UAC_FORMAT_TYPE_I_MULAW)) {
        pcm_formats |= SNDRV_PCM_FMTBIT_MU_LAW;
    }
    if (format & ~0x3f) {
        snd_printk(KERN_INFO "%d:%u:%d : unsupported format bits %#x\n",
               chip->dev->devnum, fp->iface, fp->altsetting, format);
    }
    return pcm_formats;
}


/*
 * parse the format descriptor and stores the possible sample rates
 * on the audioformat table (audio class v1).
 *
 * @dev: usb device
 * @fp: audioformat record
 * @fmt: the format descriptor
 * @offset: the start offset of descriptor pointing the rate type
 *          (7 for type I and II, 8 for type II)
 */
static int parse_audio_format_rates_v1(struct snd_usb_audio *chip, struct audioformat *fp,
                       unsigned char *fmt, int offset)
{
    int nr_rates = fmt[offset];

    if (fmt[0] < offset + 1 + 3 * (nr_rates ? nr_rates : 2)) {
        snd_printk(KERN_ERR "%d:%u:%d : invalid UAC_FORMAT_TYPE desc\n",
                   chip->dev->devnum, fp->iface, fp->altsetting);
        return -1;
    }

    if (nr_rates) {
        /*
         * build the rate table and bitmap flags
         */
        int r, idx;

        fp->rate_table = kmalloc(sizeof(int) * nr_rates, GFP_KERNEL);
        if (fp->rate_table == NULL) {
            snd_printk(KERN_ERR "cannot malloc\n");
            return -1;
        }

        fp->nr_rates = 0;
        fp->rate_min = fp->rate_max = 0;
        for (r = 0, idx = offset + 1; r < nr_rates; r++, idx += 3) {
            unsigned int rate = combine_triple(&fmt[idx]);
            if (!rate)
                continue;
            /* C-Media CM6501 mislabels its 96 kHz altsetting */
            /* Terratec Aureon 7.1 USB C-Media 6206, too */
            if (rate == 48000 && nr_rates == 1 &&
                (chip->usb_id == USB_ID(0x0d8c, 0x0201) ||
                 chip->usb_id == USB_ID(0x0d8c, 0x0102) ||
                 chip->usb_id == USB_ID(0x0ccd, 0x00b1)) &&
                fp->altsetting == 5 && fp->maxpacksize == 392)
                rate = 96000;
            /* Creative VF0470 Live Cam reports 16 kHz instead of 8kHz */
            if (rate == 16000 && chip->usb_id == USB_ID(0x041e, 0x4068))
                rate = 8000;

            fp->rate_table[fp->nr_rates] = rate;
            if (!fp->rate_min || rate < fp->rate_min)
                fp->rate_min = rate;
            if (!fp->rate_max || rate > fp->rate_max)
                fp->rate_max = rate;
            fp->rates |= snd_pcm_rate_to_rate_bit(rate);
            fp->nr_rates++;
        }
        if (!fp->nr_rates) {
            hwc_debug("All rates were zero. Skipping format!\n");
            return -1;
        }
    } else {
        /* continuous rates */
        fp->rates = SNDRV_PCM_RATE_CONTINUOUS;
        fp->rate_min = combine_triple(&fmt[offset + 1]);
        fp->rate_max = combine_triple(&fmt[offset + 4]);
    }
    return 0;
}

/*
 * Helper function to walk the array of sample rate triplets reported by
 * the device. The problem is that we need to parse whole array first to
 * get to know how many sample rates we have to expect.
 * Then fp->rate_table can be allocated and filled.
 */
static int parse_uac2_sample_rate_range(struct audioformat *fp, int nr_triplets,
                    const unsigned char *data)
{
    int i, nr_rates = 0;

    fp->rates = fp->rate_min = fp->rate_max = 0;

    for (i = 0; i < nr_triplets; i++) {
        int min = combine_quad(&data[2 + 12 * i]);
        int max = combine_quad(&data[6 + 12 * i]);
        int res = combine_quad(&data[10 + 12 * i]);
        unsigned int rate;

        if ((max < 0) || (min < 0) || (res < 0) || (max < min))
            continue;

        /*
         * for ranges with res == 1, we announce a continuous sample
         * rate range, and this function should return 0 for no further
         * parsing.
         */
        if (res == 1) {
            fp->rate_min = min;
            fp->rate_max = max;
            fp->rates = SNDRV_PCM_RATE_CONTINUOUS;
            return 0;
        }

        for (rate = min; rate <= max; rate += res) {
            if (fp->rate_table)
                fp->rate_table[nr_rates] = rate;
            if (!fp->rate_min || rate < fp->rate_min)
                fp->rate_min = rate;
            if (!fp->rate_max || rate > fp->rate_max)
                fp->rate_max = rate;
            fp->rates |= snd_pcm_rate_to_rate_bit(rate);

            nr_rates++;
            if (nr_rates >= MAX_NR_RATES) {
                snd_printk(KERN_ERR "invalid uac2 rates\n");
                break;
            }

            /* avoid endless loop */
            if (res == 0)
                break;
        }
    }

    return nr_rates;
}

/*
 * parse the format descriptor and stores the possible sample rates
 * on the audioformat table (audio class v2).
 */
static int parse_audio_format_rates_v2(struct snd_usb_audio *chip,
                       struct audioformat *fp)
{
    struct usb_device *dev = chip->dev;
    unsigned char tmp[2], *data;
    int nr_triplets, data_size, ret = 0;
    int clock = snd_usb_clock_find_source(chip, fp->clock);

    if (clock < 0) {
        snd_printk(KERN_ERR "%s(): unable to find clock source (clock %d)\n",
                __func__, clock);
        goto err;
    }

    /* get the number of sample rates first by only fetching 2 bytes */
    ret = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_RANGE,
                  USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
                  UAC2_CS_CONTROL_SAM_FREQ << 8,
                  snd_usb_ctrl_intf(chip) | (clock << 8),
                  tmp, sizeof(tmp));

    if (ret < 0) {
        snd_printk(KERN_ERR "%s(): unable to retrieve number of sample rates (clock %d)\n",
                __func__, clock);
        goto err;
    }

    nr_triplets = (tmp[1] << 8) | tmp[0];
    data_size = 2 + 12 * nr_triplets;
    data = kzalloc(data_size, GFP_KERNEL);
    if (!data) {
        ret = -ENOMEM;
        goto err;
    }

    /* now get the full information */
    ret = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_RANGE,
                  USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
                  UAC2_CS_CONTROL_SAM_FREQ << 8,
                  snd_usb_ctrl_intf(chip) | (clock << 8),
                  data, data_size);

    if (ret < 0) {
        snd_printk(KERN_ERR "%s(): unable to retrieve sample rate range (clock %d)\n",
                __func__, clock);
        ret = -EINVAL;
        goto err_free;
    }

    /* Call the triplet parser, and make sure fp->rate_table is NULL.
     * We just use the return value to know how many sample rates we
     * will have to deal with. */
    kfree(fp->rate_table);
    fp->rate_table = NULL;
    fp->nr_rates = parse_uac2_sample_rate_range(fp, nr_triplets, data);

    if (fp->nr_rates == 0) {
        /* SNDRV_PCM_RATE_CONTINUOUS */
        ret = 0;
        goto err_free;
    }

    fp->rate_table = kmalloc(sizeof(int) * fp->nr_rates, GFP_KERNEL);
    if (!fp->rate_table) {
        ret = -ENOMEM;
        goto err_free;
    }

    /* Call the triplet parser again, but this time, fp->rate_table is
     * allocated, so the rates will be stored */
    parse_uac2_sample_rate_range(fp, nr_triplets, data);

err_free:
    kfree(data);
err:
    return ret;
}

/*
 * parse the format type I and III descriptors
 */
static int parse_audio_format_i(struct snd_usb_audio *chip,
                struct audioformat *fp, int format,
                struct uac_format_type_i_continuous_descriptor *fmt,
                struct usb_host_interface *iface)
{
    struct usb_interface_descriptor *altsd = get_iface_desc(iface);
    int protocol = altsd->bInterfaceProtocol;
    int pcm_format, ret;

    if (fmt->bFormatType == UAC_FORMAT_TYPE_III) {
        /* FIXME: the format type is really IECxxx
         *        but we give normal PCM format to get the existing
         *        apps working...
         */
        switch (chip->usb_id) {

        case USB_ID(0x0763, 0x2003): /* M-Audio Audiophile USB */
            if (chip->setup == 0x00 && 
                fp->altsetting == 6)
                pcm_format = SNDRV_PCM_FORMAT_S16_BE;
            else
                pcm_format = SNDRV_PCM_FORMAT_S16_LE;
            break;
        default:
            pcm_format = SNDRV_PCM_FORMAT_S16_LE;
        }
        fp->formats = 1uLL << pcm_format;
    } else {
        fp->formats = parse_audio_format_i_type(chip, fp, format,
                            fmt, protocol);
        if (!fp->formats)
            return -1;
    }

    /* gather possible sample rates */
    /* audio class v1 reports possible sample rates as part of the
     * proprietary class specific descriptor.
     * audio class v2 uses class specific EP0 range requests for that.
     */
    switch (protocol) {
    default:
        snd_printdd(KERN_WARNING "%d:%u:%d : invalid protocol version %d, assuming v1\n",
               chip->dev->devnum, fp->iface, fp->altsetting, protocol);
        /* fall through */
    case UAC_VERSION_1:
        fp->channels = fmt->bNrChannels;
        ret = parse_audio_format_rates_v1(chip, fp, (unsigned char *) fmt, 7);
        break;
    case UAC_VERSION_2:
        /* fp->channels is already set in this case */
        ret = parse_audio_format_rates_v2(chip, fp);
        break;
    }

    if (fp->channels < 1) {
        snd_printk(KERN_ERR "%d:%u:%d : invalid channels %d\n",
               chip->dev->devnum, fp->iface, fp->altsetting, fp->channels);
        return -1;
    }

    return ret;
}

/*
 * parse the format type II descriptor
 */
static int parse_audio_format_ii(struct snd_usb_audio *chip,
                 struct audioformat *fp,
                 int format, void *_fmt,
                 struct usb_host_interface *iface)
{
    int brate, framesize, ret;
    struct usb_interface_descriptor *altsd = get_iface_desc(iface);
    int protocol = altsd->bInterfaceProtocol;

    switch (format) {
    case UAC_FORMAT_TYPE_II_AC3:
        /* FIXME: there is no AC3 format defined yet */
        // fp->formats = SNDRV_PCM_FMTBIT_AC3;
        fp->formats = SNDRV_PCM_FMTBIT_U8; /* temporary hack to receive byte streams */
        break;
    case UAC_FORMAT_TYPE_II_MPEG:
        fp->formats = SNDRV_PCM_FMTBIT_MPEG;
        break;
    default:
        snd_printd(KERN_INFO "%d:%u:%d : unknown format tag %#x is detected.  processed as MPEG.\n",
               chip->dev->devnum, fp->iface, fp->altsetting, format);
        fp->formats = SNDRV_PCM_FMTBIT_MPEG;
        break;
    }

    fp->channels = 1;

    switch (protocol) {
    default:
        snd_printdd(KERN_WARNING "%d:%u:%d : invalid protocol version %d, assuming v1\n",
               chip->dev->devnum, fp->iface, fp->altsetting, protocol);
        /* fall through */
    case UAC_VERSION_1: {
        struct uac_format_type_ii_discrete_descriptor *fmt = _fmt;
        brate = le16_to_cpu(fmt->wMaxBitRate);
        framesize = le16_to_cpu(fmt->wSamplesPerFrame);
        snd_printd(KERN_INFO "found format II with max.bitrate = %d, frame size=%d\n", brate, framesize);
        fp->frame_size = framesize;
        ret = parse_audio_format_rates_v1(chip, fp, _fmt, 8); /* fmt[8..] sample rates */
        break;
    }
    case UAC_VERSION_2: {
        struct uac_format_type_ii_ext_descriptor *fmt = _fmt;
        brate = le16_to_cpu(fmt->wMaxBitRate);
        framesize = le16_to_cpu(fmt->wSamplesPerFrame);
        snd_printd(KERN_INFO "found format II with max.bitrate = %d, frame size=%d\n", brate, framesize);
        fp->frame_size = framesize;
        ret = parse_audio_format_rates_v2(chip, fp);
        break;
    }
    }

    return ret;
}

int snd_usb_parse_audio_format(struct snd_usb_audio *chip, struct audioformat *fp,
                   int format, struct uac_format_type_i_continuous_descriptor *fmt,
                   int stream, struct usb_host_interface *iface)
{
    int err;

    switch (fmt->bFormatType) {
    case UAC_FORMAT_TYPE_I:
    case UAC_FORMAT_TYPE_III:
        err = parse_audio_format_i(chip, fp, format, fmt, iface);
        break;
    case UAC_FORMAT_TYPE_II:
        err = parse_audio_format_ii(chip, fp, format, fmt, iface);
        break;
    default:
        snd_printd(KERN_INFO "%d:%u:%d : format type %d is not supported yet\n",
               chip->dev->devnum, fp->iface, fp->altsetting,
               fmt->bFormatType);
        return -ENOTSUPP;
    }
    fp->fmt_type = fmt->bFormatType;
    if (err < 0)
        return err;
#if 1
    /* FIXME: temporary hack for extigy/audigy 2 nx/zs */
    /* extigy apparently supports sample rates other than 48k
     * but not in ordinary way.  so we enable only 48k atm.
     */
    if (chip->usb_id == USB_ID(0x041e, 0x3000) ||
        chip->usb_id == USB_ID(0x041e, 0x3020) ||
        chip->usb_id == USB_ID(0x041e, 0x3061)) {
        if (fmt->bFormatType == UAC_FORMAT_TYPE_I &&
            fp->rates != SNDRV_PCM_RATE_48000 &&
            fp->rates != SNDRV_PCM_RATE_96000)
            return -ENOTSUPP;
    }
#endif
    return 0;
}