quirks.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 <sound/control.h>
#include <sound/core.h>
#include <sound/info.h>
#include <sound/pcm.h>

#include "usbaudio.h"
#include "card.h"
#include "mixer.h"
#include "mixer_quirks.h"
#include "midi.h"
#include "quirks.h"
#include "helper.h"
#include "endpoint.h"
#include "pcm.h"
#include "clock.h"
#include "stream.h"

/*
 * handle the quirks for the contained interfaces
 */
static int create_composite_quirk(struct snd_usb_audio *chip,
                  struct usb_interface *iface,
                  struct usb_driver *driver,
                  const struct snd_usb_audio_quirk *quirk)
{
    int probed_ifnum = get_iface_desc(iface->altsetting)->bInterfaceNumber;
    int err;

    for (quirk = quirk->data; quirk->ifnum >= 0; ++quirk) {
        iface = usb_ifnum_to_if(chip->dev, quirk->ifnum);
        if (!iface)
            continue;
        if (quirk->ifnum != probed_ifnum &&
            usb_interface_claimed(iface))
            continue;
        err = snd_usb_create_quirk(chip, iface, driver, quirk);
        if (err < 0)
            return err;
        if (quirk->ifnum != probed_ifnum)
            usb_driver_claim_interface(driver, iface, (void *)-1L);
    }
    return 0;
}

static int ignore_interface_quirk(struct snd_usb_audio *chip,
                  struct usb_interface *iface,
                  struct usb_driver *driver,
                  const struct snd_usb_audio_quirk *quirk)
{
    return 0;
}


/*
 * Allow alignment on audio sub-slot (channel samples) rather than
 * on audio slots (audio frames)
 */
static int create_align_transfer_quirk(struct snd_usb_audio *chip,
                       struct usb_interface *iface,
                       struct usb_driver *driver,
                       const struct snd_usb_audio_quirk *quirk)
{
    chip->txfr_quirk = 1;
    return 1;   /* Continue with creating streams and mixer */
}

static int create_any_midi_quirk(struct snd_usb_audio *chip,
                 struct usb_interface *intf,
                 struct usb_driver *driver,
                 const struct snd_usb_audio_quirk *quirk)
{
    return snd_usbmidi_create(chip->card, intf, &chip->midi_list, quirk);
}

/*
 * create a stream for an interface with proper descriptors
 */
static int create_standard_audio_quirk(struct snd_usb_audio *chip,
                       struct usb_interface *iface,
                       struct usb_driver *driver,
                       const struct snd_usb_audio_quirk *quirk)
{
    struct usb_host_interface *alts;
    struct usb_interface_descriptor *altsd;
    int err;

    alts = &iface->altsetting[0];
    altsd = get_iface_desc(alts);
    err = snd_usb_parse_audio_interface(chip, altsd->bInterfaceNumber);
    if (err < 0) {
        snd_printk(KERN_ERR "cannot setup if %d: error %d\n",
               altsd->bInterfaceNumber, err);
        return err;
    }
    /* reset the current interface */
    usb_set_interface(chip->dev, altsd->bInterfaceNumber, 0);
    return 0;
}

/*
 * create a stream for an endpoint/altsetting without proper descriptors
 */
static int create_fixed_stream_quirk(struct snd_usb_audio *chip,
                     struct usb_interface *iface,
                     struct usb_driver *driver,
                     const struct snd_usb_audio_quirk *quirk)
{
    struct audioformat *fp;
    struct usb_host_interface *alts;
    int stream, err;
    unsigned *rate_table = NULL;

    fp = kmemdup(quirk->data, sizeof(*fp), GFP_KERNEL);
    if (!fp) {
        snd_printk(KERN_ERR "cannot memdup\n");
        return -ENOMEM;
    }
    if (fp->nr_rates > MAX_NR_RATES) {
        kfree(fp);
        return -EINVAL;
    }
    if (fp->nr_rates > 0) {
        rate_table = kmemdup(fp->rate_table,
                     sizeof(int) * fp->nr_rates, GFP_KERNEL);
        if (!rate_table) {
            kfree(fp);
            return -ENOMEM;
        }
        fp->rate_table = rate_table;
    }

    stream = (fp->endpoint & USB_DIR_IN)
        ? SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
    err = snd_usb_add_audio_stream(chip, stream, fp);
    if (err < 0) {
        kfree(fp);
        kfree(rate_table);
        return err;
    }
    if (fp->iface != get_iface_desc(&iface->altsetting[0])->bInterfaceNumber ||
        fp->altset_idx >= iface->num_altsetting) {
        kfree(fp);
        kfree(rate_table);
        return -EINVAL;
    }
    alts = &iface->altsetting[fp->altset_idx];
    fp->datainterval = snd_usb_parse_datainterval(chip, alts);
    fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
    usb_set_interface(chip->dev, fp->iface, 0);
    snd_usb_init_pitch(chip, fp->iface, alts, fp);
    snd_usb_init_sample_rate(chip, fp->iface, alts, fp, fp->rate_max);
    return 0;
}

/*
 * Create a stream for an Edirol UA-700/UA-25/UA-4FX interface.  
 * The only way to detect the sample rate is by looking at wMaxPacketSize.
 */
static int create_uaxx_quirk(struct snd_usb_audio *chip,
                 struct usb_interface *iface,
                 struct usb_driver *driver,
                 const struct snd_usb_audio_quirk *quirk)
{
    static const struct audioformat ua_format = {
        .formats = SNDRV_PCM_FMTBIT_S24_3LE,
        .channels = 2,
        .fmt_type = UAC_FORMAT_TYPE_I,
        .altsetting = 1,
        .altset_idx = 1,
        .rates = SNDRV_PCM_RATE_CONTINUOUS,
    };
    struct usb_host_interface *alts;
    struct usb_interface_descriptor *altsd;
    struct audioformat *fp;
    int stream, err;

    /* both PCM and MIDI interfaces have 2 or more altsettings */
    if (iface->num_altsetting < 2)
        return -ENXIO;
    alts = &iface->altsetting[1];
    altsd = get_iface_desc(alts);

    if (altsd->bNumEndpoints == 2) {
        static const struct snd_usb_midi_endpoint_info ua700_ep = {
            .out_cables = 0x0003,
            .in_cables  = 0x0003
        };
        static const struct snd_usb_audio_quirk ua700_quirk = {
            .type = QUIRK_MIDI_FIXED_ENDPOINT,
            .data = &ua700_ep
        };
        static const struct snd_usb_midi_endpoint_info uaxx_ep = {
            .out_cables = 0x0001,
            .in_cables  = 0x0001
        };
        static const struct snd_usb_audio_quirk uaxx_quirk = {
            .type = QUIRK_MIDI_FIXED_ENDPOINT,
            .data = &uaxx_ep
        };
        const struct snd_usb_audio_quirk *quirk =
            chip->usb_id == USB_ID(0x0582, 0x002b)
            ? &ua700_quirk : &uaxx_quirk;
        return snd_usbmidi_create(chip->card, iface,
                      &chip->midi_list, quirk);
    }

    if (altsd->bNumEndpoints != 1)
        return -ENXIO;

    fp = kmemdup(&ua_format, sizeof(*fp), GFP_KERNEL);
    if (!fp)
        return -ENOMEM;

    fp->iface = altsd->bInterfaceNumber;
    fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
    fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
    fp->datainterval = 0;
    fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);

    switch (fp->maxpacksize) {
    case 0x120:
        fp->rate_max = fp->rate_min = 44100;
        break;
    case 0x138:
    case 0x140:
        fp->rate_max = fp->rate_min = 48000;
        break;
    case 0x258:
    case 0x260:
        fp->rate_max = fp->rate_min = 96000;
        break;
    default:
        snd_printk(KERN_ERR "unknown sample rate\n");
        kfree(fp);
        return -ENXIO;
    }

    stream = (fp->endpoint & USB_DIR_IN)
        ? SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
    err = snd_usb_add_audio_stream(chip, stream, fp);
    if (err < 0) {
        kfree(fp);
        return err;
    }
    usb_set_interface(chip->dev, fp->iface, 0);
    return 0;
}

/*
 * Create a standard mixer for the specified interface.
 */
static int create_standard_mixer_quirk(struct snd_usb_audio *chip,
                       struct usb_interface *iface,
                       struct usb_driver *driver,
                       const struct snd_usb_audio_quirk *quirk)
{
    if (quirk->ifnum < 0)
        return 0;

    return snd_usb_create_mixer(chip, quirk->ifnum, 0);
}

/*
 * audio-interface quirks
 *
 * returns zero if no standard audio/MIDI parsing is needed.
 * returns a positive value if standard audio/midi interfaces are parsed
 * after this.
 * returns a negative value at error.
 */
int snd_usb_create_quirk(struct snd_usb_audio *chip,
             struct usb_interface *iface,
             struct usb_driver *driver,
             const struct snd_usb_audio_quirk *quirk)
{
    typedef int (*quirk_func_t)(struct snd_usb_audio *,
                    struct usb_interface *,
                    struct usb_driver *,
                    const struct snd_usb_audio_quirk *);
    static const quirk_func_t quirk_funcs[] = {
        [QUIRK_IGNORE_INTERFACE] = ignore_interface_quirk,
        [QUIRK_COMPOSITE] = create_composite_quirk,
        [QUIRK_MIDI_STANDARD_INTERFACE] = create_any_midi_quirk,
        [QUIRK_MIDI_FIXED_ENDPOINT] = create_any_midi_quirk,
        [QUIRK_MIDI_YAMAHA] = create_any_midi_quirk,
        [QUIRK_MIDI_MIDIMAN] = create_any_midi_quirk,
        [QUIRK_MIDI_NOVATION] = create_any_midi_quirk,
        [QUIRK_MIDI_RAW_BYTES] = create_any_midi_quirk,
        [QUIRK_MIDI_EMAGIC] = create_any_midi_quirk,
        [QUIRK_MIDI_CME] = create_any_midi_quirk,
        [QUIRK_MIDI_AKAI] = create_any_midi_quirk,
        [QUIRK_MIDI_FTDI] = create_any_midi_quirk,
        [QUIRK_AUDIO_STANDARD_INTERFACE] = create_standard_audio_quirk,
        [QUIRK_AUDIO_FIXED_ENDPOINT] = create_fixed_stream_quirk,
        [QUIRK_AUDIO_EDIROL_UAXX] = create_uaxx_quirk,
        [QUIRK_AUDIO_ALIGN_TRANSFER] = create_align_transfer_quirk,
        [QUIRK_AUDIO_STANDARD_MIXER] = create_standard_mixer_quirk,
    };

    if (quirk->type < QUIRK_TYPE_COUNT) {
        return quirk_funcs[quirk->type](chip, iface, driver, quirk);
    } else {
        snd_printd(KERN_ERR "invalid quirk type %d\n", quirk->type);
        return -ENXIO;
    }
}

/*
 * boot quirks
 */

#define EXTIGY_FIRMWARE_SIZE_OLD 794
#define EXTIGY_FIRMWARE_SIZE_NEW 483

static int snd_usb_extigy_boot_quirk(struct usb_device *dev, struct usb_interface *intf)
{
    struct usb_host_config *config = dev->actconfig;
    int err;

    if (le16_to_cpu(get_cfg_desc(config)->wTotalLength) == EXTIGY_FIRMWARE_SIZE_OLD ||
        le16_to_cpu(get_cfg_desc(config)->wTotalLength) == EXTIGY_FIRMWARE_SIZE_NEW) {
        snd_printdd("sending Extigy boot sequence...\n");
        /* Send message to force it to reconnect with full interface. */
        err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev,0),
                      0x10, 0x43, 0x0001, 0x000a, NULL, 0);
        if (err < 0) snd_printdd("error sending boot message: %d\n", err);
        err = usb_get_descriptor(dev, USB_DT_DEVICE, 0,
                &dev->descriptor, sizeof(dev->descriptor));
        config = dev->actconfig;
        if (err < 0) snd_printdd("error usb_get_descriptor: %d\n", err);
        err = usb_reset_configuration(dev);
        if (err < 0) snd_printdd("error usb_reset_configuration: %d\n", err);
        snd_printdd("extigy_boot: new boot length = %d\n",
                le16_to_cpu(get_cfg_desc(config)->wTotalLength));
        return -ENODEV; /* quit this anyway */
    }
    return 0;
}

static int snd_usb_audigy2nx_boot_quirk(struct usb_device *dev)
{
    u8 buf = 1;

    snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), 0x2a,
            USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER,
            0, 0, &buf, 1);
    if (buf == 0) {
        snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), 0x29,
                USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,
                1, 2000, NULL, 0);
        return -ENODEV;
    }
    return 0;
}

static int snd_usb_fasttrackpro_boot_quirk(struct usb_device *dev)
{
    int err;

    if (dev->actconfig->desc.bConfigurationValue == 1) {
        snd_printk(KERN_INFO "usb-audio: "
               "Fast Track Pro switching to config #2\n");
        /* This function has to be available by the usb core module.
         * if it is not avialable the boot quirk has to be left out
         * and the configuration has to be set by udev or hotplug
         * rules
         */
        err = usb_driver_set_configuration(dev, 2);
        if (err < 0) {
            snd_printdd("error usb_driver_set_configuration: %d\n",
                    err);
            return -ENODEV;
        }
    } else
        snd_printk(KERN_INFO "usb-audio: Fast Track Pro config OK\n");

    return 0;
}

/*
 * C-Media CM106/CM106+ have four 16-bit internal registers that are nicely
 * documented in the device's data sheet.
 */
static int snd_usb_cm106_write_int_reg(struct usb_device *dev, int reg, u16 value)
{
    u8 buf[4];
    buf[0] = 0x20;
    buf[1] = value & 0xff;
    buf[2] = (value >> 8) & 0xff;
    buf[3] = reg;
    return snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), USB_REQ_SET_CONFIGURATION,
                   USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
                   0, 0, &buf, 4);
}

static int snd_usb_cm106_boot_quirk(struct usb_device *dev)
{
    /*
     * Enable line-out driver mode, set headphone source to front
     * channels, enable stereo mic.
     */
    return snd_usb_cm106_write_int_reg(dev, 2, 0x8004);
}

/*
 * C-Media CM6206 is based on CM106 with two additional
 * registers that are not documented in the data sheet.
 * Values here are chosen based on sniffing USB traffic
 * under Windows.
 */
static int snd_usb_cm6206_boot_quirk(struct usb_device *dev)
{
    int err  = 0, reg;
    int val[] = {0x2004, 0x3000, 0xf800, 0x143f, 0x0000, 0x3000};

    for (reg = 0; reg < ARRAY_SIZE(val); reg++) {
        err = snd_usb_cm106_write_int_reg(dev, reg, val[reg]);
        if (err < 0)
            return err;
    }

    return err;
}

/*
 * This call will put the synth in "USB send" mode, i.e it will send MIDI
 * messages through USB (this is disabled at startup). The synth will
 * acknowledge by sending a sysex on endpoint 0x85 and by displaying a USB
 * sign on its LCD. Values here are chosen based on sniffing USB traffic
 * under Windows.
 */
static int snd_usb_accessmusic_boot_quirk(struct usb_device *dev)
{
    int err, actual_length;

    /* "midi send" enable */
    static const u8 seq[] = { 0x4e, 0x73, 0x52, 0x01 };

    void *buf = kmemdup(seq, ARRAY_SIZE(seq), GFP_KERNEL);
    if (!buf)
        return -ENOMEM;
    err = usb_interrupt_msg(dev, usb_sndintpipe(dev, 0x05), buf,
            ARRAY_SIZE(seq), &actual_length, 1000);
    kfree(buf);
    if (err < 0)
        return err;

    return 0;
}

/*
 * Some sound cards from Native Instruments are in fact compliant to the USB
 * audio standard of version 2 and other approved USB standards, even though
 * they come up as vendor-specific device when first connected.
 *
 * However, they can be told to come up with a new set of descriptors
 * upon their next enumeration, and the interfaces announced by the new
 * descriptors will then be handled by the kernel's class drivers. As the
 * product ID will also change, no further checks are required.
 */

static int snd_usb_nativeinstruments_boot_quirk(struct usb_device *dev)
{
    int ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                  0xaf, USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                  cpu_to_le16(1), 0, NULL, 0, 1000);

    if (ret < 0)
        return ret;

    usb_reset_device(dev);

    /* return -EAGAIN, so the creation of an audio interface for this
     * temporary device is aborted. The device will reconnect with a
     * new product ID */
    return -EAGAIN;
}

/*
 * Setup quirks
 */
#define MAUDIO_SET      0x01 /* parse device_setup */
#define MAUDIO_SET_COMPATIBLE   0x80 /* use only "win-compatible" interfaces */
#define MAUDIO_SET_DTS      0x02 /* enable DTS Digital Output */
#define MAUDIO_SET_96K      0x04 /* 48-96KHz rate if set, 8-48KHz otherwise */
#define MAUDIO_SET_24B      0x08 /* 24bits sample if set, 16bits otherwise */
#define MAUDIO_SET_DI       0x10 /* enable Digital Input */
#define MAUDIO_SET_MASK     0x1f /* bit mask for setup value */
#define MAUDIO_SET_24B_48K_DI    0x19 /* 24bits+48KHz+Digital Input */
#define MAUDIO_SET_24B_48K_NOTDI 0x09 /* 24bits+48KHz+No Digital Input */
#define MAUDIO_SET_16B_48K_DI    0x11 /* 16bits+48KHz+Digital Input */
#define MAUDIO_SET_16B_48K_NOTDI 0x01 /* 16bits+48KHz+No Digital Input */

static int quattro_skip_setting_quirk(struct snd_usb_audio *chip,
                      int iface, int altno)
{
    /* Reset ALL ifaces to 0 altsetting.
     * Call it for every possible altsetting of every interface.
     */
    usb_set_interface(chip->dev, iface, 0);
    if (chip->setup & MAUDIO_SET) {
        if (chip->setup & MAUDIO_SET_COMPATIBLE) {
            if (iface != 1 && iface != 2)
                return 1; /* skip all interfaces but 1 and 2 */
        } else {
            unsigned int mask;
            if (iface == 1 || iface == 2)
                return 1; /* skip interfaces 1 and 2 */
            if ((chip->setup & MAUDIO_SET_96K) && altno != 1)
                return 1; /* skip this altsetting */
            mask = chip->setup & MAUDIO_SET_MASK;
            if (mask == MAUDIO_SET_24B_48K_DI && altno != 2)
                return 1; /* skip this altsetting */
            if (mask == MAUDIO_SET_24B_48K_NOTDI && altno != 3)
                return 1; /* skip this altsetting */
            if (mask == MAUDIO_SET_16B_48K_NOTDI && altno != 4)
                return 1; /* skip this altsetting */
        }
    }
    snd_printdd(KERN_INFO
            "using altsetting %d for interface %d config %d\n",
            altno, iface, chip->setup);
    return 0; /* keep this altsetting */
}

static int audiophile_skip_setting_quirk(struct snd_usb_audio *chip,
                     int iface,
                     int altno)
{
    /* Reset ALL ifaces to 0 altsetting.
     * Call it for every possible altsetting of every interface.
     */
    usb_set_interface(chip->dev, iface, 0);

    if (chip->setup & MAUDIO_SET) {
        unsigned int mask;
        if ((chip->setup & MAUDIO_SET_DTS) && altno != 6)
            return 1; /* skip this altsetting */
        if ((chip->setup & MAUDIO_SET_96K) && altno != 1)
            return 1; /* skip this altsetting */
        mask = chip->setup & MAUDIO_SET_MASK;
        if (mask == MAUDIO_SET_24B_48K_DI && altno != 2)
            return 1; /* skip this altsetting */
        if (mask == MAUDIO_SET_24B_48K_NOTDI && altno != 3)
            return 1; /* skip this altsetting */
        if (mask == MAUDIO_SET_16B_48K_DI && altno != 4)
            return 1; /* skip this altsetting */
        if (mask == MAUDIO_SET_16B_48K_NOTDI && altno != 5)
            return 1; /* skip this altsetting */
    }

    return 0; /* keep this altsetting */
}


static int fasttrackpro_skip_setting_quirk(struct snd_usb_audio *chip,
                       int iface, int altno)
{
    /* Reset ALL ifaces to 0 altsetting.
     * Call it for every possible altsetting of every interface.
     */
    usb_set_interface(chip->dev, iface, 0);

    /* possible configuration where both inputs and only one output is
     *used is not supported by the current setup
     */
    if (chip->setup & (MAUDIO_SET | MAUDIO_SET_24B)) {
        if (chip->setup & MAUDIO_SET_96K) {
            if (altno != 3 && altno != 6)
                return 1;
        } else if (chip->setup & MAUDIO_SET_DI) {
            if (iface == 4)
                return 1; /* no analog input */
            if (altno != 2 && altno != 5)
                return 1; /* enable only altsets 2 and 5 */
        } else {
            if (iface == 5)
                return 1; /* disable digialt input */
            if (altno != 2 && altno != 5)
                return 1; /* enalbe only altsets 2 and 5 */
        }
    } else {
        /* keep only 16-Bit mode */
        if (altno != 1)
            return 1;
    }

    snd_printdd(KERN_INFO
            "using altsetting %d for interface %d config %d\n",
            altno, iface, chip->setup);
    return 0; /* keep this altsetting */
}

int snd_usb_apply_interface_quirk(struct snd_usb_audio *chip,
                  int iface,
                  int altno)
{
    /* audiophile usb: skip altsets incompatible with device_setup */
    if (chip->usb_id == USB_ID(0x0763, 0x2003))
        return audiophile_skip_setting_quirk(chip, iface, altno);
    /* quattro usb: skip altsets incompatible with device_setup */
    if (chip->usb_id == USB_ID(0x0763, 0x2001))
        return quattro_skip_setting_quirk(chip, iface, altno);
    /* fasttrackpro usb: skip altsets incompatible with device_setup */
    if (chip->usb_id == USB_ID(0x0763, 0x2012))
        return fasttrackpro_skip_setting_quirk(chip, iface, altno);

    return 0;
}

int snd_usb_apply_boot_quirk(struct usb_device *dev,
                 struct usb_interface *intf,
                 const struct snd_usb_audio_quirk *quirk)
{
    u32 id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
            le16_to_cpu(dev->descriptor.idProduct));

    switch (id) {
    case USB_ID(0x041e, 0x3000):
        /* SB Extigy needs special boot-up sequence */
        /* if more models come, this will go to the quirk list. */
        return snd_usb_extigy_boot_quirk(dev, intf);

    case USB_ID(0x041e, 0x3020):
        /* SB Audigy 2 NX needs its own boot-up magic, too */
        return snd_usb_audigy2nx_boot_quirk(dev);

    case USB_ID(0x10f5, 0x0200):
        /* C-Media CM106 / Turtle Beach Audio Advantage Roadie */
        return snd_usb_cm106_boot_quirk(dev);

    case USB_ID(0x0d8c, 0x0102):
        /* C-Media CM6206 / CM106-Like Sound Device */
    case USB_ID(0x0ccd, 0x00b1): /* Terratec Aureon 7.1 USB */
        return snd_usb_cm6206_boot_quirk(dev);

    case USB_ID(0x133e, 0x0815):
        /* Access Music VirusTI Desktop */
        return snd_usb_accessmusic_boot_quirk(dev);

    case USB_ID(0x17cc, 0x1000): /* Komplete Audio 6 */
    case USB_ID(0x17cc, 0x1010): /* Traktor Audio 6 */
    case USB_ID(0x17cc, 0x1020): /* Traktor Audio 10 */
        return snd_usb_nativeinstruments_boot_quirk(dev);
    case USB_ID(0x0763, 0x2012):  /* M-Audio Fast Track Pro USB */
        return snd_usb_fasttrackpro_boot_quirk(dev);
    }

    return 0;
}

/*
 * check if the device uses big-endian samples
 */
int snd_usb_is_big_endian_format(struct snd_usb_audio *chip, struct audioformat *fp)
{
    /* it depends on altsetting wether the device is big-endian or not */
    switch (chip->usb_id) {
    case USB_ID(0x0763, 0x2001): /* M-Audio Quattro: captured data only */
        if (fp->altsetting == 2 || fp->altsetting == 3 ||
            fp->altsetting == 5 || fp->altsetting == 6)
            return 1;
        break;
    case USB_ID(0x0763, 0x2003): /* M-Audio Audiophile USB */
        if (chip->setup == 0x00 ||
            fp->altsetting == 1 || fp->altsetting == 2 ||
            fp->altsetting == 3)
            return 1;
        break;
    case USB_ID(0x0763, 0x2012): /* M-Audio Fast Track Pro */
        if (fp->altsetting == 2 || fp->altsetting == 3 ||
            fp->altsetting == 5 || fp->altsetting == 6)
            return 1;
        break;
    }
    return 0;
}

/*
 * For E-Mu 0404USB/0202USB/TrackerPre/0204 sample rate should be set for device,
 * not for interface.
 */

enum {
    EMU_QUIRK_SR_44100HZ = 0,
    EMU_QUIRK_SR_48000HZ,
    EMU_QUIRK_SR_88200HZ,
    EMU_QUIRK_SR_96000HZ,
    EMU_QUIRK_SR_176400HZ,
    EMU_QUIRK_SR_192000HZ
};

static void set_format_emu_quirk(struct snd_usb_substream *subs,
                 struct audioformat *fmt)
{
    unsigned char emu_samplerate_id = 0;

    /* When capture is active
     * sample rate shouldn't be changed
     * by playback substream
     */
    if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK) {
        if (subs->stream->substream[SNDRV_PCM_STREAM_CAPTURE].interface != -1)
            return;
    }

    switch (fmt->rate_min) {
    case 48000:
        emu_samplerate_id = EMU_QUIRK_SR_48000HZ;
        break;
    case 88200:
        emu_samplerate_id = EMU_QUIRK_SR_88200HZ;
        break;
    case 96000:
        emu_samplerate_id = EMU_QUIRK_SR_96000HZ;
        break;
    case 176400:
        emu_samplerate_id = EMU_QUIRK_SR_176400HZ;
        break;
    case 192000:
        emu_samplerate_id = EMU_QUIRK_SR_192000HZ;
        break;
    default:
        emu_samplerate_id = EMU_QUIRK_SR_44100HZ;
        break;
    }
    snd_emuusb_set_samplerate(subs->stream->chip, emu_samplerate_id);
}

void snd_usb_set_format_quirk(struct snd_usb_substream *subs,
                  struct audioformat *fmt)
{
    switch (subs->stream->chip->usb_id) {
    case USB_ID(0x041e, 0x3f02): /* E-Mu 0202 USB */
    case USB_ID(0x041e, 0x3f04): /* E-Mu 0404 USB */
    case USB_ID(0x041e, 0x3f0a): /* E-Mu Tracker Pre */
    case USB_ID(0x041e, 0x3f19): /* E-Mu 0204 USB */
        set_format_emu_quirk(subs, fmt);
        break;
    }
}

void snd_usb_endpoint_start_quirk(struct snd_usb_endpoint *ep)
{
    /*
     * "Playback Design" products send bogus feedback data at the start
     * of the stream. Ignore them.
     */
    if ((le16_to_cpu(ep->chip->dev->descriptor.idVendor) == 0x23ba) &&
        ep->type == SND_USB_ENDPOINT_TYPE_SYNC)
        ep->skip_packets = 4;
}

void snd_usb_ctl_msg_quirk(struct usb_device *dev, unsigned int pipe,
               __u8 request, __u8 requesttype, __u16 value,
               __u16 index, void *data, __u16 size)
{
    /*
     * "Playback Design" products need a 20ms delay after each
     * class compliant request
     */
    if ((le16_to_cpu(dev->descriptor.idVendor) == 0x23ba) &&
        (requesttype & USB_TYPE_MASK) == USB_TYPE_CLASS)
        mdelay(20);
}