pod.c

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/*
 * Line6 Linux USB driver - 0.9.1beta
 *
 * Copyright (C) 2004-2010 Markus Grabner ([email protected])
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License as
 *  published by the Free Software Foundation, version 2.
 *
 */

#include <linux/slab.h>
#include <linux/wait.h>
#include <sound/control.h>

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

#define POD_SYSEX_CODE 3
#define POD_BYTES_PER_FRAME 6   /* 24bit audio (stereo) */

/* *INDENT-OFF* */

enum {
    POD_SYSEX_CLIP      = 0x0f,
    POD_SYSEX_SAVE      = 0x24,
    POD_SYSEX_SYSTEM    = 0x56,
    POD_SYSEX_SYSTEMREQ = 0x57,
    /* POD_SYSEX_UPDATE    = 0x6c, */  /* software update! */
    POD_SYSEX_STORE     = 0x71,
    POD_SYSEX_FINISH    = 0x72,
    POD_SYSEX_DUMPMEM   = 0x73,
    POD_SYSEX_DUMP      = 0x74,
    POD_SYSEX_DUMPREQ   = 0x75
    /* POD_SYSEX_DUMPMEM2  = 0x76 */   /* dumps entire internal memory of PODxt Pro */
};

enum {
    POD_monitor_level  = 0x04,
    POD_routing        = 0x05,
    POD_tuner_mute     = 0x13,
    POD_tuner_freq     = 0x15,
    POD_tuner_note     = 0x16,
    POD_tuner_pitch    = 0x17,
    POD_system_invalid = 0x10000
};

/* *INDENT-ON* */

enum {
    POD_DUMP_MEMORY = 2
};

enum {
    POD_BUSY_READ,
    POD_BUSY_WRITE,
    POD_CHANNEL_DIRTY,
    POD_SAVE_PRESSED,
    POD_BUSY_MIDISEND
};

static struct snd_ratden pod_ratden = {
    .num_min = 78125,
    .num_max = 78125,
    .num_step = 1,
    .den = 2
};

static struct line6_pcm_properties pod_pcm_properties = {
    .snd_line6_playback_hw = {
                  .info = (SNDRV_PCM_INFO_MMAP |
                       SNDRV_PCM_INFO_INTERLEAVED |
                       SNDRV_PCM_INFO_BLOCK_TRANSFER |
                       SNDRV_PCM_INFO_MMAP_VALID |
                       SNDRV_PCM_INFO_PAUSE |
#ifdef CONFIG_PM
                       SNDRV_PCM_INFO_RESUME |
#endif
                       SNDRV_PCM_INFO_SYNC_START),
                  .formats = SNDRV_PCM_FMTBIT_S24_3LE,
                  .rates = SNDRV_PCM_RATE_KNOT,
                  .rate_min = 39062,
                  .rate_max = 39063,
                  .channels_min = 2,
                  .channels_max = 2,
                  .buffer_bytes_max = 60000,
                  .period_bytes_min = 64,
                  .period_bytes_max = 8192,
                  .periods_min = 1,
                  .periods_max = 1024},
    .snd_line6_capture_hw = {
                 .info = (SNDRV_PCM_INFO_MMAP |
                      SNDRV_PCM_INFO_INTERLEAVED |
                      SNDRV_PCM_INFO_BLOCK_TRANSFER |
                      SNDRV_PCM_INFO_MMAP_VALID |
#ifdef CONFIG_PM
                      SNDRV_PCM_INFO_RESUME |
#endif
                      SNDRV_PCM_INFO_SYNC_START),
                 .formats = SNDRV_PCM_FMTBIT_S24_3LE,
                 .rates = SNDRV_PCM_RATE_KNOT,
                 .rate_min = 39062,
                 .rate_max = 39063,
                 .channels_min = 2,
                 .channels_max = 2,
                 .buffer_bytes_max = 60000,
                 .period_bytes_min = 64,
                 .period_bytes_max = 8192,
                 .periods_min = 1,
                 .periods_max = 1024},
    .snd_line6_rates = {
                .nrats = 1,
                .rats = &pod_ratden},
    .bytes_per_frame = POD_BYTES_PER_FRAME
};

static const char pod_request_channel[] = {
    0xf0, 0x00, 0x01, 0x0c, 0x03, 0x75, 0xf7
};

static const char pod_version_header[] = {
    0xf2, 0x7e, 0x7f, 0x06, 0x02
};

/* forward declarations: */
static void pod_startup2(unsigned long data);
static void pod_startup3(struct usb_line6_pod *pod);
static void pod_startup4(struct usb_line6_pod *pod);

/*
    Mark all parameters as dirty and notify waiting processes.
*/
static void pod_mark_batch_all_dirty(struct usb_line6_pod *pod)
{
    int i;

    for (i = 0; i < POD_CONTROL_SIZE; i++)
        set_bit(i, pod->param_dirty);
}

static char *pod_alloc_sysex_buffer(struct usb_line6_pod *pod, int code,
                    int size)
{
    return line6_alloc_sysex_buffer(&pod->line6, POD_SYSEX_CODE, code,
                    size);
}

/*
    Send channel dump data to the PODxt Pro.
*/
static void pod_dump(struct usb_line6_pod *pod, const unsigned char *data)
{
    int size = 1 + sizeof(pod->prog_data);
    char *sysex = pod_alloc_sysex_buffer(pod, POD_SYSEX_DUMP, size);
    if (!sysex)
        return;
    /* Don't know what this is good for, but PODxt Pro transmits it, so we
     * also do... */
    sysex[SYSEX_DATA_OFS] = 5;
    memcpy(sysex + SYSEX_DATA_OFS + 1, data, sizeof(pod->prog_data));
    line6_send_sysex_message(&pod->line6, sysex, size);
    memcpy(&pod->prog_data, data, sizeof(pod->prog_data));
    pod_mark_batch_all_dirty(pod);
    kfree(sysex);
}

/*
    Store parameter value in driver memory and mark it as dirty.
*/
static void pod_store_parameter(struct usb_line6_pod *pod, int param, int value)
{
    pod->prog_data.control[param] = value;
    set_bit(param, pod->param_dirty);
    pod->dirty = 1;
}

/*
    Handle SAVE button.
*/
static void pod_save_button_pressed(struct usb_line6_pod *pod, int type,
                    int index)
{
    pod->dirty = 0;
    set_bit(POD_SAVE_PRESSED, &pod->atomic_flags);
}

/*
    Process a completely received message.
*/
void line6_pod_process_message(struct usb_line6_pod *pod)
{
    const unsigned char *buf = pod->line6.buffer_message;

    /* filter messages by type */
    switch (buf[0] & 0xf0) {
    case LINE6_PARAM_CHANGE:
    case LINE6_PROGRAM_CHANGE:
    case LINE6_SYSEX_BEGIN:
        break;      /* handle these further down */

    default:
        return;     /* ignore all others */
    }

    /* process all remaining messages */
    switch (buf[0]) {
    case LINE6_PARAM_CHANGE | LINE6_CHANNEL_DEVICE:
        pod_store_parameter(pod, buf[1], buf[2]);
        /* intentionally no break here! */

    case LINE6_PARAM_CHANGE | LINE6_CHANNEL_HOST:
        if ((buf[1] == POD_amp_model_setup) ||
            (buf[1] == POD_effect_setup))
            /* these also affect other settings */
            line6_dump_request_async(&pod->dumpreq, &pod->line6, 0,
                         LINE6_DUMP_CURRENT);

        break;

    case LINE6_PROGRAM_CHANGE | LINE6_CHANNEL_DEVICE:
    case LINE6_PROGRAM_CHANGE | LINE6_CHANNEL_HOST:
        pod->channel_num = buf[1];
        pod->dirty = 0;
        set_bit(POD_CHANNEL_DIRTY, &pod->atomic_flags);
        line6_dump_request_async(&pod->dumpreq, &pod->line6, 0,
                     LINE6_DUMP_CURRENT);
        break;

    case LINE6_SYSEX_BEGIN | LINE6_CHANNEL_DEVICE:
    case LINE6_SYSEX_BEGIN | LINE6_CHANNEL_UNKNOWN:
        if (memcmp(buf + 1, line6_midi_id, sizeof(line6_midi_id)) == 0) {
            switch (buf[5]) {
            case POD_SYSEX_DUMP:
                if (pod->line6.message_length ==
                    sizeof(pod->prog_data) + 7) {
                    switch (pod->dumpreq.in_progress) {
                    case LINE6_DUMP_CURRENT:
                        memcpy(&pod->prog_data, buf + 7,
                               sizeof(pod->prog_data));
                        pod_mark_batch_all_dirty(pod);
                        break;

                    case POD_DUMP_MEMORY:
                        memcpy(&pod->prog_data_buf,
                               buf + 7,
                               sizeof
                               (pod->prog_data_buf));
                        break;

                    default:
                        DEBUG_MESSAGES(dev_err
                                   (pod->
                                line6.ifcdev,
                                "unknown dump code %02X\n",
                                pod->
                                dumpreq.in_progress));
                    }

                    line6_dump_finished(&pod->dumpreq);
                    pod_startup3(pod);
                } else
                    DEBUG_MESSAGES(dev_err
                               (pod->line6.ifcdev,
                            "wrong size of channel dump message (%d instead of %d)\n",
                            pod->
                            line6.message_length,
                            (int)
                            sizeof(pod->prog_data) +
                            7));

                break;

            case POD_SYSEX_SYSTEM:{
                    short value =
                        ((int)buf[7] << 12) | ((int)buf[8]
                                   << 8) |
                        ((int)buf[9] << 4) | (int)buf[10];

#define PROCESS_SYSTEM_PARAM(x) \
                    case POD_ ## x: \
                        pod->x.value = value; \
                        wake_up(&pod->x.wait); \
                        break;

                    switch (buf[6]) {
                        PROCESS_SYSTEM_PARAM
                            (monitor_level);
                        PROCESS_SYSTEM_PARAM(routing);
                        PROCESS_SYSTEM_PARAM
                            (tuner_mute);
                        PROCESS_SYSTEM_PARAM
                            (tuner_freq);
                        PROCESS_SYSTEM_PARAM
                            (tuner_note);
                        PROCESS_SYSTEM_PARAM
                            (tuner_pitch);

#undef PROCESS_SYSTEM_PARAM

                    default:
                        DEBUG_MESSAGES(dev_err
                                   (pod->
                                line6.ifcdev,
                                "unknown tuner/system response %02X\n",
                                buf[6]));
                    }

                    break;
                }

            case POD_SYSEX_FINISH:
                /* do we need to respond to this? */
                break;

            case POD_SYSEX_SAVE:
                pod_save_button_pressed(pod, buf[6], buf[7]);
                break;

            case POD_SYSEX_CLIP:
                DEBUG_MESSAGES(dev_err
                           (pod->line6.ifcdev,
                        "audio clipped\n"));
                pod->clipping.value = 1;
                wake_up(&pod->clipping.wait);
                break;

            case POD_SYSEX_STORE:
                DEBUG_MESSAGES(dev_err
                           (pod->line6.ifcdev,
                        "message %02X not yet implemented\n",
                        buf[5]));
                break;

            default:
                DEBUG_MESSAGES(dev_err
                           (pod->line6.ifcdev,
                        "unknown sysex message %02X\n",
                        buf[5]));
            }
        } else
            if (memcmp
            (buf, pod_version_header,
             sizeof(pod_version_header)) == 0) {
            pod->firmware_version =
                buf[13] * 100 + buf[14] * 10 + buf[15];
            pod->device_id =
                ((int)buf[8] << 16) | ((int)buf[9] << 8) | (int)
                buf[10];
            pod_startup4(pod);
        } else
            DEBUG_MESSAGES(dev_err
                       (pod->line6.ifcdev,
                    "unknown sysex header\n"));

        break;

    case LINE6_SYSEX_END:
        break;

    default:
        DEBUG_MESSAGES(dev_err
                   (pod->line6.ifcdev,
                "POD: unknown message %02X\n", buf[0]));
    }
}

/*
    Detect some cases that require a channel dump after sending a command to the
    device. Important notes:
    *) The actual dump request can not be sent here since we are not allowed to
    wait for the completion of the first message in this context, and sending
    the dump request before completion of the previous message leaves the POD
    in an undefined state. The dump request will be sent when the echoed
    commands are received.
    *) This method fails if a param change message is "chopped" after the first
    byte.
*/
void line6_pod_midi_postprocess(struct usb_line6_pod *pod, unsigned char *data,
                int length)
{
    int i;

    if (!pod->midi_postprocess)
        return;

    for (i = 0; i < length; ++i) {
        if (data[i] == (LINE6_PROGRAM_CHANGE | LINE6_CHANNEL_HOST)) {
            line6_invalidate_current(&pod->dumpreq);
            break;
        } else
            if ((data[i] == (LINE6_PARAM_CHANGE | LINE6_CHANNEL_HOST))
            && (i < length - 1))
            if ((data[i + 1] == POD_amp_model_setup)
                || (data[i + 1] == POD_effect_setup)) {
                line6_invalidate_current(&pod->dumpreq);
                break;
            }
    }
}

/*
    Send channel number (i.e., switch to a different sound).
*/
static void pod_send_channel(struct usb_line6_pod *pod, u8 value)
{
    line6_invalidate_current(&pod->dumpreq);

    if (line6_send_program(&pod->line6, value) == 0)
        pod->channel_num = value;
    else
        line6_dump_finished(&pod->dumpreq);
}

/*
    Transmit PODxt Pro control parameter.
*/
void line6_pod_transmit_parameter(struct usb_line6_pod *pod, int param,
                  u8 value)
{
    if (line6_transmit_parameter(&pod->line6, param, value) == 0)
        pod_store_parameter(pod, param, value);

    if ((param == POD_amp_model_setup) || (param == POD_effect_setup))  /* these also affect other settings */
        line6_invalidate_current(&pod->dumpreq);
}

/*
    Resolve value to memory location.
*/
static int pod_resolve(const char *buf, short block0, short block1,
               unsigned char *location)
{
    u8 value;
    short block;
    int ret;

    ret = kstrtou8(buf, 10, &value);
    if (ret)
        return ret;

    block = (value < 0x40) ? block0 : block1;
    value &= 0x3f;
    location[0] = block >> 7;
    location[1] = value | (block & 0x7f);
    return 0;
}

/*
    Send command to store channel/effects setup/amp setup to PODxt Pro.
*/
static ssize_t pod_send_store_command(struct device *dev, const char *buf,
                      size_t count, short block0, short block1)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    int ret;
    int size = 3 + sizeof(pod->prog_data_buf);
    char *sysex = pod_alloc_sysex_buffer(pod, POD_SYSEX_STORE, size);

    if (!sysex)
        return 0;

    sysex[SYSEX_DATA_OFS] = 5;  /* see pod_dump() */
    ret = pod_resolve(buf, block0, block1, sysex + SYSEX_DATA_OFS + 1);
    if (ret) {
        kfree(sysex);
        return ret;
    }

    memcpy(sysex + SYSEX_DATA_OFS + 3, &pod->prog_data_buf,
           sizeof(pod->prog_data_buf));

    line6_send_sysex_message(&pod->line6, sysex, size);
    kfree(sysex);
    /* needs some delay here on AMD64 platform */
    return count;
}

/*
    Send command to retrieve channel/effects setup/amp setup to PODxt Pro.
*/
static ssize_t pod_send_retrieve_command(struct device *dev, const char *buf,
                     size_t count, short block0,
                     short block1)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    int ret;
    int size = 4;
    char *sysex = pod_alloc_sysex_buffer(pod, POD_SYSEX_DUMPMEM, size);

    if (!sysex)
        return 0;

    ret = pod_resolve(buf, block0, block1, sysex + SYSEX_DATA_OFS);
    if (ret) {
        kfree(sysex);
        return ret;
    }
    sysex[SYSEX_DATA_OFS + 2] = 0;
    sysex[SYSEX_DATA_OFS + 3] = 0;
    line6_dump_started(&pod->dumpreq, POD_DUMP_MEMORY);

    if (line6_send_sysex_message(&pod->line6, sysex, size) < size)
        line6_dump_finished(&pod->dumpreq);

    kfree(sysex);
    /* needs some delay here on AMD64 platform */
    return count;
}

/*
    Generic get name function.
*/
static ssize_t get_name_generic(struct usb_line6_pod *pod, const char *str,
                char *buf)
{
    int length = 0;
    const char *p1;
    char *p2;
    char *last_non_space = buf;

    int retval = line6_dump_wait_interruptible(&pod->dumpreq);
    if (retval < 0)
        return retval;

    for (p1 = str, p2 = buf; *p1; ++p1, ++p2) {
        *p2 = *p1;
        if (*p2 != ' ')
            last_non_space = p2;
        if (++length == POD_NAME_LENGTH)
            break;
    }

    *(last_non_space + 1) = '\n';
    return last_non_space - buf + 2;
}

/*
    "read" request on "channel" special file.
*/
static ssize_t pod_get_channel(struct device *dev,
                   struct device_attribute *attr, char *buf)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    return sprintf(buf, "%d\n", pod->channel_num);
}

/*
    "write" request on "channel" special file.
*/
static ssize_t pod_set_channel(struct device *dev,
                   struct device_attribute *attr,
                   const char *buf, size_t count)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    u8 value;
    int ret;

    ret = kstrtou8(buf, 10, &value);
    if (ret)
        return ret;

    pod_send_channel(pod, value);
    return count;
}

/*
    "read" request on "name" special file.
*/
static ssize_t pod_get_name(struct device *dev, struct device_attribute *attr,
                char *buf)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    return get_name_generic(pod, pod->prog_data.header + POD_NAME_OFFSET,
                buf);
}

/*
    "read" request on "name" special file.
*/
static ssize_t pod_get_name_buf(struct device *dev,
                struct device_attribute *attr, char *buf)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    return get_name_generic(pod,
                pod->prog_data_buf.header + POD_NAME_OFFSET,
                buf);
}

/*
    "read" request on "dump" special file.
*/
static ssize_t pod_get_dump(struct device *dev, struct device_attribute *attr,
                char *buf)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    int retval = line6_dump_wait_interruptible(&pod->dumpreq);
    if (retval < 0)
        return retval;
    memcpy(buf, &pod->prog_data, sizeof(pod->prog_data));
    return sizeof(pod->prog_data);
}

/*
    "write" request on "dump" special file.
*/
static ssize_t pod_set_dump(struct device *dev, struct device_attribute *attr,
                const char *buf, size_t count)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);

    if (count != sizeof(pod->prog_data)) {
        dev_err(pod->line6.ifcdev,
            "data block must be exactly %d bytes\n",
            (int)sizeof(pod->prog_data));
        return -EINVAL;
    }

    pod_dump(pod, buf);
    return sizeof(pod->prog_data);
}

/*
    Identify system parameters related to the tuner.
*/
static bool pod_is_tuner(int code)
{
    return
        (code == POD_tuner_mute) ||
        (code == POD_tuner_freq) ||
        (code == POD_tuner_note) || (code == POD_tuner_pitch);
}

/*
    Get system parameter (as integer).
    @param tuner non-zero, if code refers to a tuner parameter
*/
static int pod_get_system_param_int(struct usb_line6_pod *pod, int *value,
                    int code, struct ValueWait *param, int sign)
{
    char *sysex;
    static const int size = 1;
    int retval = 0;

    if (((pod->prog_data.control[POD_tuner] & 0x40) == 0)
        && pod_is_tuner(code))
        return -ENODEV;

    /* send value request to device: */
    param->value = POD_system_invalid;
    sysex = pod_alloc_sysex_buffer(pod, POD_SYSEX_SYSTEMREQ, size);

    if (!sysex)
        return -ENOMEM;

    sysex[SYSEX_DATA_OFS] = code;
    line6_send_sysex_message(&pod->line6, sysex, size);
    kfree(sysex);

    /* wait for device to respond: */
    retval =
        wait_event_interruptible(param->wait,
                     param->value != POD_system_invalid);

    if (retval < 0)
        return retval;

    *value = sign ? (int)(signed short)param->value : (int)(unsigned short)
        param->value;

    if (*value == POD_system_invalid)
        *value = 0; /* don't report uninitialized values */

    return 0;
}

/*
    Get system parameter (as string).
    @param tuner non-zero, if code refers to a tuner parameter
*/
static ssize_t pod_get_system_param_string(struct usb_line6_pod *pod, char *buf,
                       int code, struct ValueWait *param,
                       int sign)
{
    int retval, value = 0;
    retval = pod_get_system_param_int(pod, &value, code, param, sign);

    if (retval < 0)
        return retval;

    return sprintf(buf, "%d\n", value);
}

/*
    Send system parameter (from integer).
    @param tuner non-zero, if code refers to a tuner parameter
*/
static int pod_set_system_param_int(struct usb_line6_pod *pod, int value,
                    int code)
{
    char *sysex;
    static const int size = 5;

    if (((pod->prog_data.control[POD_tuner] & 0x40) == 0)
        && pod_is_tuner(code))
        return -EINVAL;

    /* send value to tuner: */
    sysex = pod_alloc_sysex_buffer(pod, POD_SYSEX_SYSTEM, size);
    if (!sysex)
        return -ENOMEM;
    sysex[SYSEX_DATA_OFS] = code;
    sysex[SYSEX_DATA_OFS + 1] = (value >> 12) & 0x0f;
    sysex[SYSEX_DATA_OFS + 2] = (value >> 8) & 0x0f;
    sysex[SYSEX_DATA_OFS + 3] = (value >> 4) & 0x0f;
    sysex[SYSEX_DATA_OFS + 4] = (value) & 0x0f;
    line6_send_sysex_message(&pod->line6, sysex, size);
    kfree(sysex);
    return 0;
}

/*
    Send system parameter (from string).
    @param tuner non-zero, if code refers to a tuner parameter
*/
static ssize_t pod_set_system_param_string(struct usb_line6_pod *pod,
                       const char *buf, int count, int code,
                       unsigned short mask)
{
    int retval;
    unsigned short value = simple_strtoul(buf, NULL, 10) & mask;
    retval = pod_set_system_param_int(pod, value, code);
    return (retval < 0) ? retval : count;
}

/*
    "read" request on "dump_buf" special file.
*/
static ssize_t pod_get_dump_buf(struct device *dev,
                struct device_attribute *attr, char *buf)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    int retval = line6_dump_wait_interruptible(&pod->dumpreq);
    if (retval < 0)
        return retval;
    memcpy(buf, &pod->prog_data_buf, sizeof(pod->prog_data_buf));
    return sizeof(pod->prog_data_buf);
}

/*
    "write" request on "dump_buf" special file.
*/
static ssize_t pod_set_dump_buf(struct device *dev,
                struct device_attribute *attr,
                const char *buf, size_t count)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);

    if (count != sizeof(pod->prog_data)) {
        dev_err(pod->line6.ifcdev,
            "data block must be exactly %d bytes\n",
            (int)sizeof(pod->prog_data));
        return -EINVAL;
    }

    memcpy(&pod->prog_data_buf, buf, sizeof(pod->prog_data));
    return sizeof(pod->prog_data);
}

/*
    "write" request on "finish" special file.
*/
static ssize_t pod_set_finish(struct device *dev,
                  struct device_attribute *attr,
                  const char *buf, size_t count)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    int size = 0;
    char *sysex = pod_alloc_sysex_buffer(pod, POD_SYSEX_FINISH, size);
    if (!sysex)
        return 0;
    line6_send_sysex_message(&pod->line6, sysex, size);
    kfree(sysex);
    return count;
}

/*
    "write" request on "store_channel" special file.
*/
static ssize_t pod_set_store_channel(struct device *dev,
                     struct device_attribute *attr,
                     const char *buf, size_t count)
{
    return pod_send_store_command(dev, buf, count, 0x0000, 0x00c0);
}

/*
    "write" request on "store_effects_setup" special file.
*/
static ssize_t pod_set_store_effects_setup(struct device *dev,
                       struct device_attribute *attr,
                       const char *buf, size_t count)
{
    return pod_send_store_command(dev, buf, count, 0x0080, 0x0080);
}

/*
    "write" request on "store_amp_setup" special file.
*/
static ssize_t pod_set_store_amp_setup(struct device *dev,
                       struct device_attribute *attr,
                       const char *buf, size_t count)
{
    return pod_send_store_command(dev, buf, count, 0x0040, 0x0100);
}

/*
    "write" request on "retrieve_channel" special file.
*/
static ssize_t pod_set_retrieve_channel(struct device *dev,
                    struct device_attribute *attr,
                    const char *buf, size_t count)
{
    return pod_send_retrieve_command(dev, buf, count, 0x0000, 0x00c0);
}

/*
    "write" request on "retrieve_effects_setup" special file.
*/
static ssize_t pod_set_retrieve_effects_setup(struct device *dev,
                          struct device_attribute *attr,
                          const char *buf, size_t count)
{
    return pod_send_retrieve_command(dev, buf, count, 0x0080, 0x0080);
}

/*
    "write" request on "retrieve_amp_setup" special file.
*/
static ssize_t pod_set_retrieve_amp_setup(struct device *dev,
                      struct device_attribute *attr,
                      const char *buf, size_t count)
{
    return pod_send_retrieve_command(dev, buf, count, 0x0040, 0x0100);
}

/*
    "read" request on "dirty" special file.
*/
static ssize_t pod_get_dirty(struct device *dev, struct device_attribute *attr,
                 char *buf)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    buf[0] = pod->dirty ? '1' : '0';
    buf[1] = '\n';
    return 2;
}

/*
    "read" request on "midi_postprocess" special file.
*/
static ssize_t pod_get_midi_postprocess(struct device *dev,
                    struct device_attribute *attr,
                    char *buf)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    return sprintf(buf, "%d\n", pod->midi_postprocess);
}

/*
    "write" request on "midi_postprocess" special file.
*/
static ssize_t pod_set_midi_postprocess(struct device *dev,
                    struct device_attribute *attr,
                    const char *buf, size_t count)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    u8 value;
    int ret;

    ret = kstrtou8(buf, 10, &value);
    if (ret)
        return ret;

    pod->midi_postprocess = value ? 1 : 0;
    return count;
}

/*
    "read" request on "serial_number" special file.
*/
static ssize_t pod_get_serial_number(struct device *dev,
                     struct device_attribute *attr, char *buf)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    return sprintf(buf, "%d\n", pod->serial_number);
}

/*
    "read" request on "firmware_version" special file.
*/
static ssize_t pod_get_firmware_version(struct device *dev,
                    struct device_attribute *attr,
                    char *buf)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    return sprintf(buf, "%d.%02d\n", pod->firmware_version / 100,
               pod->firmware_version % 100);
}

/*
    "read" request on "device_id" special file.
*/
static ssize_t pod_get_device_id(struct device *dev,
                 struct device_attribute *attr, char *buf)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    return sprintf(buf, "%d\n", pod->device_id);
}

/*
    "read" request on "clip" special file.
*/
static ssize_t pod_wait_for_clip(struct device *dev,
                 struct device_attribute *attr, char *buf)
{
    struct usb_interface *interface = to_usb_interface(dev);
    struct usb_line6_pod *pod = usb_get_intfdata(interface);
    return wait_event_interruptible(pod->clipping.wait,
                    pod->clipping.value != 0);
}

/*
    POD startup procedure.
    This is a sequence of functions with special requirements (e.g., must
    not run immediately after initialization, must not run in interrupt
    context). After the last one has finished, the device is ready to use.
*/

static void pod_startup1(struct usb_line6_pod *pod)
{
    CHECK_STARTUP_PROGRESS(pod->startup_progress, POD_STARTUP_INIT);

    /* delay startup procedure: */
    line6_start_timer(&pod->startup_timer, POD_STARTUP_DELAY, pod_startup2,
              (unsigned long)pod);
}

static void pod_startup2(unsigned long data)
{
    struct usb_line6_pod *pod = (struct usb_line6_pod *)data;

    /* schedule another startup procedure until startup is complete: */
    if (pod->startup_progress >= POD_STARTUP_LAST)
        return;

    pod->startup_progress = POD_STARTUP_DUMPREQ;
    line6_start_timer(&pod->startup_timer, POD_STARTUP_DELAY, pod_startup2,
              (unsigned long)pod);

    /* current channel dump: */
    line6_dump_request_async(&pod->dumpreq, &pod->line6, 0,
                 LINE6_DUMP_CURRENT);
}

static void pod_startup3(struct usb_line6_pod *pod)
{
    struct usb_line6 *line6 = &pod->line6;
    CHECK_STARTUP_PROGRESS(pod->startup_progress, POD_STARTUP_VERSIONREQ);

    /* request firmware version: */
    line6_version_request_async(line6);
}

static void pod_startup4(struct usb_line6_pod *pod)
{
    CHECK_STARTUP_PROGRESS(pod->startup_progress, POD_STARTUP_WORKQUEUE);

    /* schedule work for global work queue: */
    schedule_work(&pod->startup_work);
}

static void pod_startup5(struct work_struct *work)
{
    struct usb_line6_pod *pod =
        container_of(work, struct usb_line6_pod, startup_work);
    struct usb_line6 *line6 = &pod->line6;

    CHECK_STARTUP_PROGRESS(pod->startup_progress, POD_STARTUP_SETUP);

    /* serial number: */
    line6_read_serial_number(&pod->line6, &pod->serial_number);

    /* ALSA audio interface: */
    line6_register_audio(line6);

    /* device files: */
    line6_pod_create_files(pod->firmware_version,
                   line6->properties->device_bit, line6->ifcdev);
}

#define POD_GET_SYSTEM_PARAM(code, sign) \
static ssize_t pod_get_ ## code(struct device *dev, \
                struct device_attribute *attr, char *buf) \
{ \
    struct usb_interface *interface = to_usb_interface(dev); \
    struct usb_line6_pod *pod = usb_get_intfdata(interface); \
    return pod_get_system_param_string(pod, buf, POD_ ## code,  \
                       &pod->code, sign);       \
}

#define POD_GET_SET_SYSTEM_PARAM(code, mask, sign) \
POD_GET_SYSTEM_PARAM(code, sign) \
static ssize_t pod_set_ ## code(struct device *dev, \
                struct device_attribute *attr, \
                const char *buf, size_t count) \
{ \
    struct usb_interface *interface = to_usb_interface(dev); \
    struct usb_line6_pod *pod = usb_get_intfdata(interface); \
    return pod_set_system_param_string(pod, buf, count, POD_ ## code, mask); \
}

POD_GET_SET_SYSTEM_PARAM(monitor_level, 0xffff, 0);
POD_GET_SET_SYSTEM_PARAM(routing, 0x0003, 0);
POD_GET_SET_SYSTEM_PARAM(tuner_mute, 0x0001, 0);
POD_GET_SET_SYSTEM_PARAM(tuner_freq, 0xffff, 0);
POD_GET_SYSTEM_PARAM(tuner_note, 1);
POD_GET_SYSTEM_PARAM(tuner_pitch, 1);

#undef GET_SET_SYSTEM_PARAM
#undef GET_SYSTEM_PARAM

/* POD special files: */
static DEVICE_ATTR(channel, S_IWUSR | S_IRUGO, pod_get_channel,
           pod_set_channel);
static DEVICE_ATTR(clip, S_IRUGO, pod_wait_for_clip, line6_nop_write);
static DEVICE_ATTR(device_id, S_IRUGO, pod_get_device_id, line6_nop_write);
static DEVICE_ATTR(dirty, S_IRUGO, pod_get_dirty, line6_nop_write);
static DEVICE_ATTR(dump, S_IWUSR | S_IRUGO, pod_get_dump, pod_set_dump);
static DEVICE_ATTR(dump_buf, S_IWUSR | S_IRUGO, pod_get_dump_buf,
           pod_set_dump_buf);
static DEVICE_ATTR(finish, S_IWUSR, line6_nop_read, pod_set_finish);
static DEVICE_ATTR(firmware_version, S_IRUGO, pod_get_firmware_version,
           line6_nop_write);
static DEVICE_ATTR(midi_postprocess, S_IWUSR | S_IRUGO,
           pod_get_midi_postprocess, pod_set_midi_postprocess);
static DEVICE_ATTR(monitor_level, S_IWUSR | S_IRUGO, pod_get_monitor_level,
           pod_set_monitor_level);
static DEVICE_ATTR(name, S_IRUGO, pod_get_name, line6_nop_write);
static DEVICE_ATTR(name_buf, S_IRUGO, pod_get_name_buf, line6_nop_write);
static DEVICE_ATTR(retrieve_amp_setup, S_IWUSR, line6_nop_read,
           pod_set_retrieve_amp_setup);
static DEVICE_ATTR(retrieve_channel, S_IWUSR, line6_nop_read,
           pod_set_retrieve_channel);
static DEVICE_ATTR(retrieve_effects_setup, S_IWUSR, line6_nop_read,
           pod_set_retrieve_effects_setup);
static DEVICE_ATTR(routing, S_IWUSR | S_IRUGO, pod_get_routing,
           pod_set_routing);
static DEVICE_ATTR(serial_number, S_IRUGO, pod_get_serial_number,
           line6_nop_write);
static DEVICE_ATTR(store_amp_setup, S_IWUSR, line6_nop_read,
           pod_set_store_amp_setup);
static DEVICE_ATTR(store_channel, S_IWUSR, line6_nop_read,
           pod_set_store_channel);
static DEVICE_ATTR(store_effects_setup, S_IWUSR, line6_nop_read,
           pod_set_store_effects_setup);
static DEVICE_ATTR(tuner_freq, S_IWUSR | S_IRUGO, pod_get_tuner_freq,
           pod_set_tuner_freq);
static DEVICE_ATTR(tuner_mute, S_IWUSR | S_IRUGO, pod_get_tuner_mute,
           pod_set_tuner_mute);
static DEVICE_ATTR(tuner_note, S_IRUGO, pod_get_tuner_note, line6_nop_write);
static DEVICE_ATTR(tuner_pitch, S_IRUGO, pod_get_tuner_pitch, line6_nop_write);

#ifdef CONFIG_LINE6_USB_RAW
static DEVICE_ATTR(raw, S_IWUSR, line6_nop_read, line6_set_raw);
#endif

/* control info callback */
static int snd_pod_control_monitor_info(struct snd_kcontrol *kcontrol,
                    struct snd_ctl_elem_info *uinfo)
{
    uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
    uinfo->count = 1;
    uinfo->value.integer.min = 0;
    uinfo->value.integer.max = 65535;
    return 0;
}

/* control get callback */
static int snd_pod_control_monitor_get(struct snd_kcontrol *kcontrol,
                       struct snd_ctl_elem_value *ucontrol)
{
    struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);
    struct usb_line6_pod *pod = (struct usb_line6_pod *)line6pcm->line6;
    ucontrol->value.integer.value[0] = pod->monitor_level.value;
    return 0;
}

/* control put callback */
static int snd_pod_control_monitor_put(struct snd_kcontrol *kcontrol,
                       struct snd_ctl_elem_value *ucontrol)
{
    struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);
    struct usb_line6_pod *pod = (struct usb_line6_pod *)line6pcm->line6;

    if (ucontrol->value.integer.value[0] == pod->monitor_level.value)
        return 0;

    pod->monitor_level.value = ucontrol->value.integer.value[0];
    pod_set_system_param_int(pod, ucontrol->value.integer.value[0],
                 POD_monitor_level);
    return 1;
}

/* control definition */
static struct snd_kcontrol_new pod_control_monitor = {
    .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
    .name = "Monitor Playback Volume",
    .index = 0,
    .access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
    .info = snd_pod_control_monitor_info,
    .get = snd_pod_control_monitor_get,
    .put = snd_pod_control_monitor_put
};

/*
    POD destructor.
*/
static void pod_destruct(struct usb_interface *interface)
{
    struct usb_line6_pod *pod = usb_get_intfdata(interface);

    if (pod == NULL)
        return;
    line6_cleanup_audio(&pod->line6);

    del_timer(&pod->startup_timer);
    cancel_work_sync(&pod->startup_work);

    /* free dump request data: */
    line6_dumpreq_destruct(&pod->dumpreq);
}

/*
    Create sysfs entries.
*/
static int pod_create_files2(struct device *dev)
{
    int err;

    CHECK_RETURN(device_create_file(dev, &dev_attr_channel));
    CHECK_RETURN(device_create_file(dev, &dev_attr_clip));
    CHECK_RETURN(device_create_file(dev, &dev_attr_device_id));
    CHECK_RETURN(device_create_file(dev, &dev_attr_dirty));
    CHECK_RETURN(device_create_file(dev, &dev_attr_dump));
    CHECK_RETURN(device_create_file(dev, &dev_attr_dump_buf));
    CHECK_RETURN(device_create_file(dev, &dev_attr_finish));
    CHECK_RETURN(device_create_file(dev, &dev_attr_firmware_version));
    CHECK_RETURN(device_create_file(dev, &dev_attr_midi_postprocess));
    CHECK_RETURN(device_create_file(dev, &dev_attr_monitor_level));
    CHECK_RETURN(device_create_file(dev, &dev_attr_name));
    CHECK_RETURN(device_create_file(dev, &dev_attr_name_buf));
    CHECK_RETURN(device_create_file(dev, &dev_attr_retrieve_amp_setup));
    CHECK_RETURN(device_create_file(dev, &dev_attr_retrieve_channel));
    CHECK_RETURN(device_create_file(dev, &dev_attr_retrieve_effects_setup));
    CHECK_RETURN(device_create_file(dev, &dev_attr_routing));
    CHECK_RETURN(device_create_file(dev, &dev_attr_serial_number));
    CHECK_RETURN(device_create_file(dev, &dev_attr_store_amp_setup));
    CHECK_RETURN(device_create_file(dev, &dev_attr_store_channel));
    CHECK_RETURN(device_create_file(dev, &dev_attr_store_effects_setup));
    CHECK_RETURN(device_create_file(dev, &dev_attr_tuner_freq));
    CHECK_RETURN(device_create_file(dev, &dev_attr_tuner_mute));
    CHECK_RETURN(device_create_file(dev, &dev_attr_tuner_note));
    CHECK_RETURN(device_create_file(dev, &dev_attr_tuner_pitch));

#ifdef CONFIG_LINE6_USB_RAW
    CHECK_RETURN(device_create_file(dev, &dev_attr_raw));
#endif

    return 0;
}

/*
     Try to init POD device.
*/
static int pod_try_init(struct usb_interface *interface,
            struct usb_line6_pod *pod)
{
    int err;
    struct usb_line6 *line6 = &pod->line6;

    init_timer(&pod->startup_timer);
    INIT_WORK(&pod->startup_work, pod_startup5);

    if ((interface == NULL) || (pod == NULL))
        return -ENODEV;

    pod->channel_num = 255;

    /* initialize wait queues: */
    init_waitqueue_head(&pod->monitor_level.wait);
    init_waitqueue_head(&pod->routing.wait);
    init_waitqueue_head(&pod->tuner_mute.wait);
    init_waitqueue_head(&pod->tuner_freq.wait);
    init_waitqueue_head(&pod->tuner_note.wait);
    init_waitqueue_head(&pod->tuner_pitch.wait);
    init_waitqueue_head(&pod->clipping.wait);

    memset(pod->param_dirty, 0xff, sizeof(pod->param_dirty));

    /* initialize USB buffers: */
    err = line6_dumpreq_init(&pod->dumpreq, pod_request_channel,
                 sizeof(pod_request_channel));
    if (err < 0) {
        dev_err(&interface->dev, "Out of memory\n");
        return -ENOMEM;
    }

    /* create sysfs entries: */
    err = pod_create_files2(&interface->dev);
    if (err < 0)
        return err;

    /* initialize audio system: */
    err = line6_init_audio(line6);
    if (err < 0)
        return err;

    /* initialize MIDI subsystem: */
    err = line6_init_midi(line6);
    if (err < 0)
        return err;

    /* initialize PCM subsystem: */
    err = line6_init_pcm(line6, &pod_pcm_properties);
    if (err < 0)
        return err;

    /* register monitor control: */
    err = snd_ctl_add(line6->card,
              snd_ctl_new1(&pod_control_monitor, line6->line6pcm));
    if (err < 0)
        return err;

    /*
       When the sound card is registered at this point, the PODxt Live
       displays "Invalid Code Error 07", so we do it later in the event
       handler.
     */

    if (pod->line6.properties->capabilities & LINE6_BIT_CONTROL) {
        pod->monitor_level.value = POD_system_invalid;

        /* initiate startup procedure: */
        pod_startup1(pod);
    }

    return 0;
}

/*
     Init POD device (and clean up in case of failure).
*/
int line6_pod_init(struct usb_interface *interface, struct usb_line6_pod *pod)
{
    int err = pod_try_init(interface, pod);

    if (err < 0)
        pod_destruct(interface);

    return err;
}

/*
    POD device disconnected.
*/
void line6_pod_disconnect(struct usb_interface *interface)
{
    struct usb_line6_pod *pod;

    if (interface == NULL)
        return;
    pod = usb_get_intfdata(interface);

    if (pod != NULL) {
        struct snd_line6_pcm *line6pcm = pod->line6.line6pcm;
        struct device *dev = &interface->dev;

        if (line6pcm != NULL)
            line6_pcm_disconnect(line6pcm);

        if (dev != NULL) {
            /* remove sysfs entries: */
            line6_pod_remove_files(pod->firmware_version,
                           pod->line6.
                           properties->device_bit, dev);

            device_remove_file(dev, &dev_attr_channel);
            device_remove_file(dev, &dev_attr_clip);
            device_remove_file(dev, &dev_attr_device_id);
            device_remove_file(dev, &dev_attr_dirty);
            device_remove_file(dev, &dev_attr_dump);
            device_remove_file(dev, &dev_attr_dump_buf);
            device_remove_file(dev, &dev_attr_finish);
            device_remove_file(dev, &dev_attr_firmware_version);
            device_remove_file(dev, &dev_attr_midi_postprocess);
            device_remove_file(dev, &dev_attr_monitor_level);
            device_remove_file(dev, &dev_attr_name);
            device_remove_file(dev, &dev_attr_name_buf);
            device_remove_file(dev, &dev_attr_retrieve_amp_setup);
            device_remove_file(dev, &dev_attr_retrieve_channel);
            device_remove_file(dev,
                       &dev_attr_retrieve_effects_setup);
            device_remove_file(dev, &dev_attr_routing);
            device_remove_file(dev, &dev_attr_serial_number);
            device_remove_file(dev, &dev_attr_store_amp_setup);
            device_remove_file(dev, &dev_attr_store_channel);
            device_remove_file(dev, &dev_attr_store_effects_setup);
            device_remove_file(dev, &dev_attr_tuner_freq);
            device_remove_file(dev, &dev_attr_tuner_mute);
            device_remove_file(dev, &dev_attr_tuner_note);
            device_remove_file(dev, &dev_attr_tuner_pitch);

#ifdef CONFIG_LINE6_USB_RAW
            device_remove_file(dev, &dev_attr_raw);
#endif
        }
    }

    pod_destruct(interface);
}