// SPDX-License-Identifier: GPL-2.0-or-later
/*
 */

#include <linux/init.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/usb/audio.h>
#include <linux/usb/audio-v2.h>
#include <linux/usb/audio-v3.h>

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

#include "usbaudio.h"
#include "card.h"
#include "quirks.h"
#include "helper.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 (v1/v2) or AudioStreaming descriptor (v3)
 */
static u64 parse_audio_format_i_type(struct snd_usb_audio *chip,
                                     struct audioformat *fp,
                                     u64 format, void *_fmt)
{
        int sample_width, sample_bytes;
        u64 pcm_formats = 0;
        u64 dsd_formats = 0;

        switch (fp->protocol) {
        case UAC_VERSION_1:
        default: {
                struct uac_format_type_i_discrete_descriptor *fmt = _fmt;
                if (format >= 64) {
                        usb_audio_info(chip,
                                       "%u:%d: invalid format type 0x%llx is detected, processed as PCM\n",
                                       fp->iface, fp->altsetting, format);
                        format = UAC_FORMAT_TYPE_I_PCM;
                }
                sample_width = fmt->bBitResolution;
                sample_bytes = fmt->bSubframeSize;
                format = 1ULL << format;
                break;
        }

        case UAC_VERSION_2: {
                struct uac_format_type_i_ext_descriptor *fmt = _fmt;
                sample_width = fmt->bBitResolution;
                sample_bytes = fmt->bSubslotSize;

                if (format & UAC2_FORMAT_TYPE_I_RAW_DATA) {
                        pcm_formats |= SNDRV_PCM_FMTBIT_SPECIAL;
                        /* flag potentially raw DSD capable altsettings */
                        fp->dsd_raw = true;
                        /* clear special format bit to avoid "unsupported format" msg below */
                        format &= ~UAC2_FORMAT_TYPE_I_RAW_DATA;
                }

                format <<= 1;
                break;
        }
        case UAC_VERSION_3: {
                struct uac3_as_header_descriptor *as = _fmt;

                sample_width = as->bBitResolution;
                sample_bytes = as->bSubslotSize;

                if (format & UAC3_FORMAT_TYPE_I_RAW_DATA) {
                        pcm_formats |= SNDRV_PCM_FMTBIT_SPECIAL;
                        /* clear special format bit to avoid "unsupported format" msg below */
                        format &= ~UAC3_FORMAT_TYPE_I_RAW_DATA;
                }

                format <<= 1;
                break;
        }
        }

        fp->fmt_bits = sample_width;
        fp->fmt_sz = sample_bytes;

        if ((pcm_formats == 0) &&
            (format == 0 || format == BIT(UAC_FORMAT_TYPE_I_UNDEFINED))) {
                /* some devices don't define this correctly... */
                usb_audio_info(chip, "%u:%d : format type 0 is detected, processed as PCM\n",
                        fp->iface, fp->altsetting);
                format = BIT(UAC_FORMAT_TYPE_I_PCM);
        }
        if (format & BIT(UAC_FORMAT_TYPE_I_PCM)) {
                if (((chip->usb_id == USB_ID(0x0582, 0x0016)) ||
                     /* Edirol SD-90 */
                     (chip->usb_id == USB_ID(0x0582, 0x000c))) &&
                     /* Roland SC-D70 */
                    sample_width == 24 && sample_bytes == 2)
                        sample_bytes = 3;
                else if (sample_width > sample_bytes * 8) {
                        usb_audio_info(chip, "%u:%d : sample bitwidth %d in over sample bytes %d\n",
                                 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:
                        usb_audio_info(chip,
                                 "%u:%d : unsupported sample bitwidth %d in %d bytes\n",
                                 fp->iface, fp->altsetting,
                                 sample_width, sample_bytes);
                        break;
                }
        }
        if (format & BIT(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 & BIT(UAC_FORMAT_TYPE_I_IEEE_FLOAT))
                pcm_formats |= SNDRV_PCM_FMTBIT_FLOAT_LE;
        if (format & BIT(UAC_FORMAT_TYPE_I_ALAW))
                pcm_formats |= SNDRV_PCM_FMTBIT_A_LAW;
        if (format & BIT(UAC_FORMAT_TYPE_I_MULAW))
                pcm_formats |= SNDRV_PCM_FMTBIT_MU_LAW;
        if (format & ~0x3f) {
                usb_audio_info(chip,
                         "%u:%d : unsupported format bits %#llx\n",
                         fp->iface, fp->altsetting, format);
        }

        dsd_formats |= snd_usb_interface_dsd_format_quirks(chip, fp, sample_bytes);
        if (dsd_formats && !fp->dsd_dop)
                pcm_formats = dsd_formats;

        return pcm_formats;
}

static int set_fixed_rate(struct audioformat *fp, int rate, int rate_bits)
{
        kfree(fp->rate_table);
        fp->rate_table = kmalloc(sizeof(int), GFP_KERNEL);
        if (!fp->rate_table)
                return -ENOMEM;
        fp->nr_rates = 1;
        fp->rate_min = rate;
        fp->rate_max = rate;
        fp->rates = rate_bits;
        fp->rate_table[0] = rate;
        return 0;
}

/* set up rate_min, rate_max and rates from the rate table */
static void set_rate_table_min_max(struct audioformat *fp)
{
        unsigned int rate;
        int i;

        fp->rate_min = INT_MAX;
        fp->rate_max = 0;
        fp->rates = 0;
        for (i = 0; i < fp->nr_rates; i++) {
                rate = fp->rate_table[i];
                fp->rate_min = min(fp->rate_min, rate);
                fp->rate_max = max(fp->rate_max, rate);
                fp->rates |= snd_pcm_rate_to_rate_bit(rate);
        }
}

/*
 * 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)) {
                usb_audio_err(chip,
                        "%u:%d : invalid UAC_FORMAT_TYPE desc\n",
                        fp->iface, fp->altsetting);
                return -EINVAL;
        }

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

                fp->rate_table = kmalloc_array(nr_rates, sizeof(int),
                                               GFP_KERNEL);
                if (fp->rate_table == NULL)
                        return -ENOMEM;

                fp->nr_rates = 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 */
                        /* Ozone Z90 USB C-Media, 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(0x0d8c, 0x0078) ||
                             chip->usb_id == USB_ID(0x0ccd, 0x00b1)) &&
                            fp->altsetting == 5 && fp->maxpacksize == 392)
                                rate = 96000;
                        /* Creative VF0420/VF0470 Live Cams report 16 kHz instead of 8kHz */
                        if (rate == 16000 &&
                            (chip->usb_id == USB_ID(0x041e, 0x4064) ||
                             chip->usb_id == USB_ID(0x041e, 0x4068)))
                                rate = 8000;

                        fp->rate_table[fp->nr_rates++] = rate;
                }
                if (!fp->nr_rates) {
                        usb_audio_info(chip,
                                       "%u:%d: All rates were zero\n",
                                       fp->iface, fp->altsetting);
                        return -EINVAL;
                }
                set_rate_table_min_max(fp);
        } 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]);
        }

        /* Jabra Evolve 65 headset */
        if (chip->usb_id == USB_ID(0x0b0e, 0x030b) ||
            chip->usb_id == USB_ID(0x0b0e, 0x030c)) {
                /* only 48kHz for playback while keeping 16kHz for capture */
                if (fp->nr_rates != 1)
                        return set_fixed_rate(fp, 48000, SNDRV_PCM_RATE_48000);
        }

        return 0;
}


/*
 * Presonus Studio 1810c supports a limited set of sampling
 * rates per altsetting but reports the full set each time.
 * If we don't filter out the unsupported rates and attempt
 * to configure the card, it will hang refusing to do any
 * further audio I/O until a hard reset is performed.
 *
 * The list of supported rates per altsetting (set of available
 * I/O channels) is described in the owner's manual, section 2.2.
 */
static bool s1810c_valid_sample_rate(struct audioformat *fp,
                                     unsigned int rate)
{
        switch (fp->altsetting) {
        case 1:
                /* All ADAT ports available */
                return rate <= 48000;
        case 2:
                /* Half of ADAT ports available */
                return (rate == 88200 || rate == 96000);
        case 3:
                /* Analog I/O only (no S/PDIF nor ADAT) */
                return rate >= 176400;
        default:
                return false;
        }
        return false;
}

/*
 * Focusrite devices use rate pairs: 44100/48000, 88200/96000, and
 * 176400/192000. Return true if rate is in the pair for max_rate.
 */
static bool focusrite_rate_pair(unsigned int rate,
                                unsigned int max_rate)
{
        switch (max_rate) {
        case 48000:  return rate == 44100 || rate == 48000;
        case 96000:  return rate == 88200 || rate == 96000;
        case 192000: return rate == 176400 || rate == 192000;
        default:     return true;
        }
}

/*
 * Focusrite devices report all supported rates in a single clock
 * source but only a subset is valid per altsetting.
 *
 * Detection uses two descriptor features:
 *
 * 1. Format Type descriptor bLength == 10: non-standard extension
 *    with max sample rate in bytes 6..9.
 *
 * 2. bmControls VAL_ALT_SETTINGS readable bit: when set, the device
 *    only supports the highest rate pair for that altsetting, and when
 *    clear, all rates up to max_rate are valid.
 *
 * For devices without the bLength == 10 extension but with
 * VAL_ALT_SETTINGS readable and multiple altsettings (only seen in
 * Scarlett 18i8 3rd Gen playback), fall back to the Focusrite
 * convention: alt 1 = 48kHz, alt 2 = 96kHz, alt 3 = 192kHz.
 */
static bool focusrite_valid_sample_rate(struct snd_usb_audio *chip,
                                        struct audioformat *fp,
                                        unsigned int rate)
{
        struct usb_interface *iface;
        struct usb_host_interface *alts;
        struct uac2_as_header_descriptor *as;
        unsigned char *fmt;
        unsigned int max_rate;
        bool val_alt;

        alts = snd_usb_get_host_interface(chip, fp->iface, fp->altsetting);
        if (!alts)
                return true;

        fmt = snd_usb_find_csint_desc(alts->extra, alts->extralen,
                                      NULL, UAC_FORMAT_TYPE);
        if (!fmt)
                return true;

        as = snd_usb_find_csint_desc(alts->extra, alts->extralen,
                                     NULL, UAC_AS_GENERAL);
        if (!as)
                return true;

        val_alt = uac_v2v3_control_is_readable(as->bmControls,
                                               UAC2_AS_VAL_ALT_SETTINGS);

        if (fmt[0] == 10) { /* bLength */
                max_rate = combine_quad(&fmt[6]);

                if (val_alt)
                        return focusrite_rate_pair(rate, max_rate);

                /* No val_alt: rates fall through from higher */
                switch (max_rate) {
                case 192000:
                        if (rate == 176400 || rate == 192000)
                                return true;
                        fallthrough;
                case 96000:
                        if (rate == 88200 || rate == 96000)
                                return true;
                        fallthrough;
                case 48000:
                        return (rate == 44100 || rate == 48000);
                default:
                        usb_audio_info(chip,
                                "%u:%d : unexpected max rate: %u\n",
                                fp->iface, fp->altsetting, max_rate);
                        return true;
                }
        }

        if (!val_alt)
                return true;

        /* Multi-altsetting device with val_alt but no max_rate
         * in the format descriptor. Use Focusrite convention:
         * alt 1 = 48kHz, alt 2 = 96kHz, alt 3 = 192kHz.
         */
        iface = usb_ifnum_to_if(chip->dev, fp->iface);
        if (!iface || iface->num_altsetting <= 2)
                return true;

        switch (fp->altsetting) {
        case 1:         max_rate = 48000; break;
        case 2:         max_rate = 96000; break;
        case 3:         max_rate = 192000; break;
        default:        return true;
        }

        return focusrite_rate_pair(rate, max_rate);
}

/*
 * 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 snd_usb_audio *chip,
                                        struct audioformat *fp, int nr_triplets,
                                        const unsigned char *data)
{
        int i, nr_rates = 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) {

                        /* Filter out invalid rates on Presonus Studio 1810c */
                        if (chip->usb_id == USB_ID(0x194f, 0x010c) &&
                            !s1810c_valid_sample_rate(fp, rate))
                                goto skip_rate;
                        /* Filter out invalid rates on Presonus Studio 1824c */
                        if (chip->usb_id == USB_ID(0x194f, 0x010d) &&
                            !s1810c_valid_sample_rate(fp, rate))
                                goto skip_rate;
                        /* Filter out invalid rates on Presonus Studio 1824 */
                        if (chip->usb_id == USB_ID(0x194f, 0x0107) &&
                            !s1810c_valid_sample_rate(fp, rate))
                                goto skip_rate;

                        /* Filter out invalid rates on Focusrite devices */
                        if (USB_ID_VENDOR(chip->usb_id) == 0x1235 &&
                            !focusrite_valid_sample_rate(chip, fp, rate))
                                goto skip_rate;

                        if (fp->rate_table)
                                fp->rate_table[nr_rates] = rate;
                        nr_rates++;
                        if (nr_rates >= MAX_NR_RATES) {
                                usb_audio_err(chip, "invalid uac2 rates\n");
                                break;
                        }

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

        return nr_rates;
}

/* Line6 Helix series and the Rode Rodecaster Pro don't support the
 * UAC2_CS_RANGE usb function call. Return a static table of known
 * clock rates.
 */
static int line6_parse_audio_format_rates_quirk(struct snd_usb_audio *chip,
                                                struct audioformat *fp)
{
        switch (chip->usb_id) {
        case USB_ID(0x0e41, 0x4241): /* Line6 Helix */
        case USB_ID(0x0e41, 0x4242): /* Line6 Helix Rack */
        case USB_ID(0x0e41, 0x4244): /* Line6 Helix LT */
        case USB_ID(0x0e41, 0x4246): /* Line6 HX-Stomp */
        case USB_ID(0x0e41, 0x4253): /* Line6 HX-Stomp XL */
        case USB_ID(0x0e41, 0x4247): /* Line6 Pod Go */
        case USB_ID(0x0e41, 0x4248): /* Line6 Helix >= fw 2.82 */
        case USB_ID(0x0e41, 0x4249): /* Line6 Helix Rack >= fw 2.82 */
        case USB_ID(0x0e41, 0x424a): /* Line6 Helix LT >= fw 2.82 */
        case USB_ID(0x0e41, 0x424b): /* Line6 Pod Go */
        case USB_ID(0x19f7, 0x0011): /* Rode Rodecaster Pro */
                return set_fixed_rate(fp, 48000, SNDRV_PCM_RATE_48000);
        }

        return -ENODEV;
}

/* check whether the given altsetting is supported for the already set rate */
static bool check_valid_altsetting_v2v3(struct snd_usb_audio *chip, int iface,
                                        int altsetting)
{
        struct usb_device *dev = chip->dev;
        __le64 raw_data = 0;
        u64 data;
        int err;

        /* we assume 64bit is enough for any altsettings */
        if (snd_BUG_ON(altsetting >= 64 - 8))
                return false;

        err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
                              USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
                              UAC2_AS_VAL_ALT_SETTINGS << 8,
                              iface, &raw_data, sizeof(raw_data));
        if (err < 0)
                return false;

        data = le64_to_cpu(raw_data);
        /* first byte contains the bitmap size */
        if ((data & 0xff) * 8 < altsetting)
                return false;
        if (data & (1ULL << (altsetting + 8)))
                return true;

        return false;
}

/*
 * Validate each sample rate with the altsetting
 * Rebuild the rate table if only partial values are valid
 */
static int validate_sample_rate_table_v2v3(struct snd_usb_audio *chip,
                                           struct audioformat *fp,
                                           int clock)
{
        struct usb_device *dev = chip->dev;
        struct usb_host_interface *alts;
        unsigned int *table;
        unsigned int nr_rates;
        int i, err;
        u32 bmControls;

        /* performing the rate verification may lead to unexpected USB bus
         * behavior afterwards by some unknown reason.  Do this only for the
         * known devices.
         */
        if (!(chip->quirk_flags & QUIRK_FLAG_VALIDATE_RATES))
                return 0; /* don't perform the validation as default */

        alts = snd_usb_get_host_interface(chip, fp->iface, fp->altsetting);
        if (!alts)
                return 0;

        if (fp->protocol == UAC_VERSION_3) {
                struct uac3_as_header_descriptor *as = snd_usb_find_csint_desc(
                                alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
                bmControls = le32_to_cpu(as->bmControls);
        } else {
                struct uac2_as_header_descriptor *as = snd_usb_find_csint_desc(
                                alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
                bmControls = as->bmControls;
        }

        if (!uac_v2v3_control_is_readable(bmControls,
                                UAC2_AS_VAL_ALT_SETTINGS))
                return 0;

        table = kcalloc(fp->nr_rates, sizeof(*table), GFP_KERNEL);
        if (!table)
                return -ENOMEM;

        /* clear the interface altsetting at first */
        usb_set_interface(dev, fp->iface, 0);

        nr_rates = 0;
        for (i = 0; i < fp->nr_rates; i++) {
                err = snd_usb_set_sample_rate_v2v3(chip, fp, clock,
                                                   fp->rate_table[i]);
                if (err < 0)
                        continue;

                if (check_valid_altsetting_v2v3(chip, fp->iface, fp->altsetting))
                        table[nr_rates++] = fp->rate_table[i];
        }

        if (!nr_rates) {
                usb_audio_dbg(chip,
                              "No valid sample rate available for %d:%d, assuming a firmware bug\n",
                              fp->iface, fp->altsetting);
                nr_rates = fp->nr_rates; /* continue as is */
        }

        if (fp->nr_rates == nr_rates) {
                kfree(table);
                return 0;
        }

        kfree(fp->rate_table);
        fp->rate_table = table;
        fp->nr_rates = nr_rates;
        return 0;
}

/*
 * parse the format descriptor and stores the possible sample rates
 * on the audioformat table (audio class v2 and v3).
 */
static int parse_audio_format_rates_v2v3(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, ret_l6;
        int clock = snd_usb_clock_find_source(chip, fp, false);
        struct usb_host_interface *ctrl_intf;

        ctrl_intf = snd_usb_find_ctrl_interface(chip, fp->iface);
        if (clock < 0) {
                dev_err(&dev->dev,
                        "%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(ctrl_intf) | (clock << 8),
                              tmp, sizeof(tmp));

        if (ret < 0) {
                /* line6 helix devices don't support UAC2_CS_CONTROL_SAM_FREQ call */
                ret_l6 = line6_parse_audio_format_rates_quirk(chip, fp);
                if (ret_l6 == -ENODEV) {
                        /* no line6 device found continue showing the error */
                        dev_err(&dev->dev,
                                "%s(): unable to retrieve number of sample rates (clock %d)\n",
                                __func__, clock);
                        goto err;
                }
                if (ret_l6 == 0) {
                        dev_info(&dev->dev,
                                "%s(): unable to retrieve number of sample rates: set it to a predefined value (clock %d).\n",
                                __func__, clock);
                        return 0;
                }
                ret = ret_l6;
                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(ctrl_intf) | (clock << 8),
                              data, data_size);

        if (ret < 0) {
                dev_err(&dev->dev,
                        "%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(chip, fp, nr_triplets, data);

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

        fp->rate_table = kmalloc_array(fp->nr_rates, sizeof(int), 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(chip, fp, nr_triplets, data);

        ret = validate_sample_rate_table_v2v3(chip, fp, clock);
        if (ret < 0)
                goto err_free;

        set_rate_table_min_max(fp);

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, u64 format,
                                void *_fmt)
{
        snd_pcm_format_t pcm_format;
        unsigned int fmt_type;
        int ret;

        switch (fp->protocol) {
        default:
        case UAC_VERSION_1:
        case UAC_VERSION_2: {
                struct uac_format_type_i_continuous_descriptor *fmt = _fmt;

                fmt_type = fmt->bFormatType;
                break;
        }
        case UAC_VERSION_3: {
                /* fp->fmt_type is already set in this case */
                fmt_type = fp->fmt_type;
                break;
        }
        }

        if (fmt_type == 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 = pcm_format_to_bits(pcm_format);
        } else {
                fp->formats = parse_audio_format_i_type(chip, fp, format, _fmt);
                if (!fp->formats)
                        return -EINVAL;
        }

        /* 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 (fp->protocol) {
        default:
        case UAC_VERSION_1: {
                struct uac_format_type_i_continuous_descriptor *fmt = _fmt;

                fp->channels = fmt->bNrChannels;
                ret = parse_audio_format_rates_v1(chip, fp, (unsigned char *) fmt, 7);
                break;
        }
        case UAC_VERSION_2:
        case UAC_VERSION_3: {
                /* fp->channels is already set in this case */
                ret = parse_audio_format_rates_v2v3(chip, fp);
                break;
        }
        }

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

        return ret;
}

/*
 * parse the format type II descriptor
 */
static int parse_audio_format_ii(struct snd_usb_audio *chip,
                                 struct audioformat *fp,
                                 u64 format, void *_fmt)
{
        int brate, framesize, ret;

        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:
                usb_audio_info(chip,
                         "%u:%d : unknown format tag %#llx is detected.  processed as MPEG.\n",
                         fp->iface, fp->altsetting, format);
                fp->formats = SNDRV_PCM_FMTBIT_MPEG;
                break;
        }

        fp->channels = 1;

        switch (fp->protocol) {
        default:
        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);
                usb_audio_info(chip, "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);
                usb_audio_info(chip, "found format II with max.bitrate = %d, frame size=%d\n", brate, framesize);
                fp->frame_size = framesize;
                ret = parse_audio_format_rates_v2v3(chip, fp);
                break;
        }
        }

        return ret;
}

int snd_usb_parse_audio_format(struct snd_usb_audio *chip,
                               struct audioformat *fp, u64 format,
                               struct uac_format_type_i_continuous_descriptor *fmt,
                               int stream)
{
        int err;

        switch (fmt->bFormatType) {
        case UAC_FORMAT_TYPE_I:
        case UAC_FORMAT_TYPE_III:
                err = parse_audio_format_i(chip, fp, format, fmt);
                break;
        case UAC_FORMAT_TYPE_II:
                err = parse_audio_format_ii(chip, fp, format, fmt);
                break;
        default:
                usb_audio_info(chip,
                         "%u:%d : format type %d is not supported yet\n",
                         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;
}

int snd_usb_parse_audio_format_v3(struct snd_usb_audio *chip,
                               struct audioformat *fp,
                               struct uac3_as_header_descriptor *as,
                               int stream)
{
        u64 format = le64_to_cpu(as->bmFormats);
        int err;

        /*
         * Type I format bits are D0..D6
         * This test works because type IV is not supported
         */
        if (format & 0x7f)
                fp->fmt_type = UAC_FORMAT_TYPE_I;
        else
                fp->fmt_type = UAC_FORMAT_TYPE_III;

        err = parse_audio_format_i(chip, fp, format, as);
        if (err < 0)
                return err;

        return 0;
}