pcm_native.c

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/*
 *  Digital Audio (PCM) abstract layer
 *  Copyright (c) by Jaroslav Kysela <[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; 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/mm.h>
#include <linux/module.h>
#include <linux/file.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/pm_qos.h>
#include <linux/uio.h>
#include <linux/dma-mapping.h>
#include <sound/core.h>
#include <sound/control.h>
#include <sound/info.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/timer.h>
#include <sound/minors.h>
#include <asm/io.h>
#if defined(CONFIG_MIPS) && defined(CONFIG_DMA_NONCOHERENT)
#include <dma-coherence.h>
#endif

/*
 *  Compatibility
 */

struct snd_pcm_hw_params_old {
    unsigned int flags;
    unsigned int masks[SNDRV_PCM_HW_PARAM_SUBFORMAT -
               SNDRV_PCM_HW_PARAM_ACCESS + 1];
    struct snd_interval intervals[SNDRV_PCM_HW_PARAM_TICK_TIME -
                    SNDRV_PCM_HW_PARAM_SAMPLE_BITS + 1];
    unsigned int rmask;
    unsigned int cmask;
    unsigned int info;
    unsigned int msbits;
    unsigned int rate_num;
    unsigned int rate_den;
    snd_pcm_uframes_t fifo_size;
    unsigned char reserved[64];
};

#ifdef CONFIG_SND_SUPPORT_OLD_API
#define SNDRV_PCM_IOCTL_HW_REFINE_OLD _IOWR('A', 0x10, struct snd_pcm_hw_params_old)
#define SNDRV_PCM_IOCTL_HW_PARAMS_OLD _IOWR('A', 0x11, struct snd_pcm_hw_params_old)

static int snd_pcm_hw_refine_old_user(struct snd_pcm_substream *substream,
                      struct snd_pcm_hw_params_old __user * _oparams);
static int snd_pcm_hw_params_old_user(struct snd_pcm_substream *substream,
                      struct snd_pcm_hw_params_old __user * _oparams);
#endif
static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream);

/*
 *
 */

DEFINE_RWLOCK(snd_pcm_link_rwlock);
EXPORT_SYMBOL(snd_pcm_link_rwlock);

static DECLARE_RWSEM(snd_pcm_link_rwsem);

static inline mm_segment_t snd_enter_user(void)
{
    mm_segment_t fs = get_fs();
    set_fs(get_ds());
    return fs;
}

static inline void snd_leave_user(mm_segment_t fs)
{
    set_fs(fs);
}



int snd_pcm_info(struct snd_pcm_substream *substream, struct snd_pcm_info *info)
{
    struct snd_pcm_runtime *runtime;
    struct snd_pcm *pcm = substream->pcm;
    struct snd_pcm_str *pstr = substream->pstr;

    memset(info, 0, sizeof(*info));
    info->card = pcm->card->number;
    info->device = pcm->device;
    info->stream = substream->stream;
    info->subdevice = substream->number;
    strlcpy(info->id, pcm->id, sizeof(info->id));
    strlcpy(info->name, pcm->name, sizeof(info->name));
    info->dev_class = pcm->dev_class;
    info->dev_subclass = pcm->dev_subclass;
    info->subdevices_count = pstr->substream_count;
    info->subdevices_avail = pstr->substream_count - pstr->substream_opened;
    strlcpy(info->subname, substream->name, sizeof(info->subname));
    runtime = substream->runtime;
    /* AB: FIXME!!! This is definitely nonsense */
    if (runtime) {
        info->sync = runtime->sync;
        substream->ops->ioctl(substream, SNDRV_PCM_IOCTL1_INFO, info);
    }
    return 0;
}

int snd_pcm_info_user(struct snd_pcm_substream *substream,
              struct snd_pcm_info __user * _info)
{
    struct snd_pcm_info *info;
    int err;

    info = kmalloc(sizeof(*info), GFP_KERNEL);
    if (! info)
        return -ENOMEM;
    err = snd_pcm_info(substream, info);
    if (err >= 0) {
        if (copy_to_user(_info, info, sizeof(*info)))
            err = -EFAULT;
    }
    kfree(info);
    return err;
}

#undef RULES_DEBUG

#ifdef RULES_DEBUG
#define HW_PARAM(v) [SNDRV_PCM_HW_PARAM_##v] = #v
static const char * const snd_pcm_hw_param_names[] = {
    HW_PARAM(ACCESS),
    HW_PARAM(FORMAT),
    HW_PARAM(SUBFORMAT),
    HW_PARAM(SAMPLE_BITS),
    HW_PARAM(FRAME_BITS),
    HW_PARAM(CHANNELS),
    HW_PARAM(RATE),
    HW_PARAM(PERIOD_TIME),
    HW_PARAM(PERIOD_SIZE),
    HW_PARAM(PERIOD_BYTES),
    HW_PARAM(PERIODS),
    HW_PARAM(BUFFER_TIME),
    HW_PARAM(BUFFER_SIZE),
    HW_PARAM(BUFFER_BYTES),
    HW_PARAM(TICK_TIME),
};
#endif

int snd_pcm_hw_refine(struct snd_pcm_substream *substream, 
              struct snd_pcm_hw_params *params)
{
    unsigned int k;
    struct snd_pcm_hardware *hw;
    struct snd_interval *i = NULL;
    struct snd_mask *m = NULL;
    struct snd_pcm_hw_constraints *constrs = &substream->runtime->hw_constraints;
    unsigned int rstamps[constrs->rules_num];
    unsigned int vstamps[SNDRV_PCM_HW_PARAM_LAST_INTERVAL + 1];
    unsigned int stamp = 2;
    int changed, again;

    params->info = 0;
    params->fifo_size = 0;
    if (params->rmask & (1 << SNDRV_PCM_HW_PARAM_SAMPLE_BITS))
        params->msbits = 0;
    if (params->rmask & (1 << SNDRV_PCM_HW_PARAM_RATE)) {
        params->rate_num = 0;
        params->rate_den = 0;
    }

    for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++) {
        m = hw_param_mask(params, k);
        if (snd_mask_empty(m))
            return -EINVAL;
        if (!(params->rmask & (1 << k)))
            continue;
#ifdef RULES_DEBUG
        printk(KERN_DEBUG "%s = ", snd_pcm_hw_param_names[k]);
        printk("%04x%04x%04x%04x -> ", m->bits[3], m->bits[2], m->bits[1], m->bits[0]);
#endif
        changed = snd_mask_refine(m, constrs_mask(constrs, k));
#ifdef RULES_DEBUG
        printk("%04x%04x%04x%04x\n", m->bits[3], m->bits[2], m->bits[1], m->bits[0]);
#endif
        if (changed)
            params->cmask |= 1 << k;
        if (changed < 0)
            return changed;
    }

    for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) {
        i = hw_param_interval(params, k);
        if (snd_interval_empty(i))
            return -EINVAL;
        if (!(params->rmask & (1 << k)))
            continue;
#ifdef RULES_DEBUG
        printk(KERN_DEBUG "%s = ", snd_pcm_hw_param_names[k]);
        if (i->empty)
            printk("empty");
        else
            printk("%c%u %u%c", 
                   i->openmin ? '(' : '[', i->min,
                   i->max, i->openmax ? ')' : ']');
        printk(" -> ");
#endif
        changed = snd_interval_refine(i, constrs_interval(constrs, k));
#ifdef RULES_DEBUG
        if (i->empty)
            printk("empty\n");
        else 
            printk("%c%u %u%c\n", 
                   i->openmin ? '(' : '[', i->min,
                   i->max, i->openmax ? ')' : ']');
#endif
        if (changed)
            params->cmask |= 1 << k;
        if (changed < 0)
            return changed;
    }

    for (k = 0; k < constrs->rules_num; k++)
        rstamps[k] = 0;
    for (k = 0; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) 
        vstamps[k] = (params->rmask & (1 << k)) ? 1 : 0;
    do {
        again = 0;
        for (k = 0; k < constrs->rules_num; k++) {
            struct snd_pcm_hw_rule *r = &constrs->rules[k];
            unsigned int d;
            int doit = 0;
            if (r->cond && !(r->cond & params->flags))
                continue;
            for (d = 0; r->deps[d] >= 0; d++) {
                if (vstamps[r->deps[d]] > rstamps[k]) {
                    doit = 1;
                    break;
                }
            }
            if (!doit)
                continue;
#ifdef RULES_DEBUG
            printk(KERN_DEBUG "Rule %d [%p]: ", k, r->func);
            if (r->var >= 0) {
                printk("%s = ", snd_pcm_hw_param_names[r->var]);
                if (hw_is_mask(r->var)) {
                    m = hw_param_mask(params, r->var);
                    printk("%x", *m->bits);
                } else {
                    i = hw_param_interval(params, r->var);
                    if (i->empty)
                        printk("empty");
                    else
                        printk("%c%u %u%c", 
                               i->openmin ? '(' : '[', i->min,
                               i->max, i->openmax ? ')' : ']');
                }
            }
#endif
            changed = r->func(params, r);
#ifdef RULES_DEBUG
            if (r->var >= 0) {
                printk(" -> ");
                if (hw_is_mask(r->var))
                    printk("%x", *m->bits);
                else {
                    if (i->empty)
                        printk("empty");
                    else
                        printk("%c%u %u%c", 
                               i->openmin ? '(' : '[', i->min,
                               i->max, i->openmax ? ')' : ']');
                }
            }
            printk("\n");
#endif
            rstamps[k] = stamp;
            if (changed && r->var >= 0) {
                params->cmask |= (1 << r->var);
                vstamps[r->var] = stamp;
                again = 1;
            }
            if (changed < 0)
                return changed;
            stamp++;
        }
    } while (again);
    if (!params->msbits) {
        i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
        if (snd_interval_single(i))
            params->msbits = snd_interval_value(i);
    }

    if (!params->rate_den) {
        i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
        if (snd_interval_single(i)) {
            params->rate_num = snd_interval_value(i);
            params->rate_den = 1;
        }
    }

    hw = &substream->runtime->hw;
    if (!params->info)
        params->info = hw->info & ~SNDRV_PCM_INFO_FIFO_IN_FRAMES;
    if (!params->fifo_size) {
        m = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
        i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
        if (snd_mask_min(m) == snd_mask_max(m) &&
                    snd_interval_min(i) == snd_interval_max(i)) {
            changed = substream->ops->ioctl(substream,
                    SNDRV_PCM_IOCTL1_FIFO_SIZE, params);
            if (changed < 0)
                return changed;
        }
    }
    params->rmask = 0;
    return 0;
}

EXPORT_SYMBOL(snd_pcm_hw_refine);

static int snd_pcm_hw_refine_user(struct snd_pcm_substream *substream,
                  struct snd_pcm_hw_params __user * _params)
{
    struct snd_pcm_hw_params *params;
    int err;

    params = memdup_user(_params, sizeof(*params));
    if (IS_ERR(params))
        return PTR_ERR(params);

    err = snd_pcm_hw_refine(substream, params);
    if (copy_to_user(_params, params, sizeof(*params))) {
        if (!err)
            err = -EFAULT;
    }

    kfree(params);
    return err;
}

static int period_to_usecs(struct snd_pcm_runtime *runtime)
{
    int usecs;

    if (! runtime->rate)
        return -1; /* invalid */

    /* take 75% of period time as the deadline */
    usecs = (750000 / runtime->rate) * runtime->period_size;
    usecs += ((750000 % runtime->rate) * runtime->period_size) /
        runtime->rate;

    return usecs;
}

static void snd_pcm_set_state(struct snd_pcm_substream *substream, int state)
{
    snd_pcm_stream_lock_irq(substream);
    if (substream->runtime->status->state != SNDRV_PCM_STATE_DISCONNECTED)
        substream->runtime->status->state = state;
    snd_pcm_stream_unlock_irq(substream);
}

static int snd_pcm_hw_params(struct snd_pcm_substream *substream,
                 struct snd_pcm_hw_params *params)
{
    struct snd_pcm_runtime *runtime;
    int err, usecs;
    unsigned int bits;
    snd_pcm_uframes_t frames;

    if (PCM_RUNTIME_CHECK(substream))
        return -ENXIO;
    runtime = substream->runtime;
    snd_pcm_stream_lock_irq(substream);
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_OPEN:
    case SNDRV_PCM_STATE_SETUP:
    case SNDRV_PCM_STATE_PREPARED:
        break;
    default:
        snd_pcm_stream_unlock_irq(substream);
        return -EBADFD;
    }
    snd_pcm_stream_unlock_irq(substream);
#if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
    if (!substream->oss.oss)
#endif
        if (atomic_read(&substream->mmap_count))
            return -EBADFD;

    params->rmask = ~0U;
    err = snd_pcm_hw_refine(substream, params);
    if (err < 0)
        goto _error;

    err = snd_pcm_hw_params_choose(substream, params);
    if (err < 0)
        goto _error;

    if (substream->ops->hw_params != NULL) {
        err = substream->ops->hw_params(substream, params);
        if (err < 0)
            goto _error;
    }

    runtime->access = params_access(params);
    runtime->format = params_format(params);
    runtime->subformat = params_subformat(params);
    runtime->channels = params_channels(params);
    runtime->rate = params_rate(params);
    runtime->period_size = params_period_size(params);
    runtime->periods = params_periods(params);
    runtime->buffer_size = params_buffer_size(params);
    runtime->info = params->info;
    runtime->rate_num = params->rate_num;
    runtime->rate_den = params->rate_den;
    runtime->no_period_wakeup =
            (params->info & SNDRV_PCM_INFO_NO_PERIOD_WAKEUP) &&
            (params->flags & SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP);

    bits = snd_pcm_format_physical_width(runtime->format);
    runtime->sample_bits = bits;
    bits *= runtime->channels;
    runtime->frame_bits = bits;
    frames = 1;
    while (bits % 8 != 0) {
        bits *= 2;
        frames *= 2;
    }
    runtime->byte_align = bits / 8;
    runtime->min_align = frames;

    /* Default sw params */
    runtime->tstamp_mode = SNDRV_PCM_TSTAMP_NONE;
    runtime->period_step = 1;
    runtime->control->avail_min = runtime->period_size;
    runtime->start_threshold = 1;
    runtime->stop_threshold = runtime->buffer_size;
    runtime->silence_threshold = 0;
    runtime->silence_size = 0;
    runtime->boundary = runtime->buffer_size;
    while (runtime->boundary * 2 <= LONG_MAX - runtime->buffer_size)
        runtime->boundary *= 2;

    snd_pcm_timer_resolution_change(substream);
    snd_pcm_set_state(substream, SNDRV_PCM_STATE_SETUP);

    if (pm_qos_request_active(&substream->latency_pm_qos_req))
        pm_qos_remove_request(&substream->latency_pm_qos_req);
    if ((usecs = period_to_usecs(runtime)) >= 0)
        pm_qos_add_request(&substream->latency_pm_qos_req,
                   PM_QOS_CPU_DMA_LATENCY, usecs);
    return 0;
 _error:
    /* hardware might be unusable from this time,
       so we force application to retry to set
       the correct hardware parameter settings */
    snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN);
    if (substream->ops->hw_free != NULL)
        substream->ops->hw_free(substream);
    return err;
}

static int snd_pcm_hw_params_user(struct snd_pcm_substream *substream,
                  struct snd_pcm_hw_params __user * _params)
{
    struct snd_pcm_hw_params *params;
    int err;

    params = memdup_user(_params, sizeof(*params));
    if (IS_ERR(params))
        return PTR_ERR(params);

    err = snd_pcm_hw_params(substream, params);
    if (copy_to_user(_params, params, sizeof(*params))) {
        if (!err)
            err = -EFAULT;
    }

    kfree(params);
    return err;
}

static int snd_pcm_hw_free(struct snd_pcm_substream *substream)
{
    struct snd_pcm_runtime *runtime;
    int result = 0;

    if (PCM_RUNTIME_CHECK(substream))
        return -ENXIO;
    runtime = substream->runtime;
    snd_pcm_stream_lock_irq(substream);
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_SETUP:
    case SNDRV_PCM_STATE_PREPARED:
        break;
    default:
        snd_pcm_stream_unlock_irq(substream);
        return -EBADFD;
    }
    snd_pcm_stream_unlock_irq(substream);
    if (atomic_read(&substream->mmap_count))
        return -EBADFD;
    if (substream->ops->hw_free)
        result = substream->ops->hw_free(substream);
    snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN);
    pm_qos_remove_request(&substream->latency_pm_qos_req);
    return result;
}

static int snd_pcm_sw_params(struct snd_pcm_substream *substream,
                 struct snd_pcm_sw_params *params)
{
    struct snd_pcm_runtime *runtime;
    int err;

    if (PCM_RUNTIME_CHECK(substream))
        return -ENXIO;
    runtime = substream->runtime;
    snd_pcm_stream_lock_irq(substream);
    if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
        snd_pcm_stream_unlock_irq(substream);
        return -EBADFD;
    }
    snd_pcm_stream_unlock_irq(substream);

    if (params->tstamp_mode > SNDRV_PCM_TSTAMP_LAST)
        return -EINVAL;
    if (params->avail_min == 0)
        return -EINVAL;
    if (params->silence_size >= runtime->boundary) {
        if (params->silence_threshold != 0)
            return -EINVAL;
    } else {
        if (params->silence_size > params->silence_threshold)
            return -EINVAL;
        if (params->silence_threshold > runtime->buffer_size)
            return -EINVAL;
    }
    err = 0;
    snd_pcm_stream_lock_irq(substream);
    runtime->tstamp_mode = params->tstamp_mode;
    runtime->period_step = params->period_step;
    runtime->control->avail_min = params->avail_min;
    runtime->start_threshold = params->start_threshold;
    runtime->stop_threshold = params->stop_threshold;
    runtime->silence_threshold = params->silence_threshold;
    runtime->silence_size = params->silence_size;
        params->boundary = runtime->boundary;
    if (snd_pcm_running(substream)) {
        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
            runtime->silence_size > 0)
            snd_pcm_playback_silence(substream, ULONG_MAX);
        err = snd_pcm_update_state(substream, runtime);
    }
    snd_pcm_stream_unlock_irq(substream);
    return err;
}

static int snd_pcm_sw_params_user(struct snd_pcm_substream *substream,
                  struct snd_pcm_sw_params __user * _params)
{
    struct snd_pcm_sw_params params;
    int err;
    if (copy_from_user(&params, _params, sizeof(params)))
        return -EFAULT;
    err = snd_pcm_sw_params(substream, &params);
    if (copy_to_user(_params, &params, sizeof(params)))
        return -EFAULT;
    return err;
}

int snd_pcm_status(struct snd_pcm_substream *substream,
           struct snd_pcm_status *status)
{
    struct snd_pcm_runtime *runtime = substream->runtime;

    snd_pcm_stream_lock_irq(substream);
    status->state = runtime->status->state;
    status->suspended_state = runtime->status->suspended_state;
    if (status->state == SNDRV_PCM_STATE_OPEN)
        goto _end;
    status->trigger_tstamp = runtime->trigger_tstamp;
    if (snd_pcm_running(substream)) {
        snd_pcm_update_hw_ptr(substream);
        if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
            status->tstamp = runtime->status->tstamp;
            goto _tstamp_end;
        }
    }
    snd_pcm_gettime(runtime, &status->tstamp);
 _tstamp_end:
    status->appl_ptr = runtime->control->appl_ptr;
    status->hw_ptr = runtime->status->hw_ptr;
    if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
        status->avail = snd_pcm_playback_avail(runtime);
        if (runtime->status->state == SNDRV_PCM_STATE_RUNNING ||
            runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
            status->delay = runtime->buffer_size - status->avail;
            status->delay += runtime->delay;
        } else
            status->delay = 0;
    } else {
        status->avail = snd_pcm_capture_avail(runtime);
        if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
            status->delay = status->avail + runtime->delay;
        else
            status->delay = 0;
    }
    status->avail_max = runtime->avail_max;
    status->overrange = runtime->overrange;
    runtime->avail_max = 0;
    runtime->overrange = 0;
 _end:
    snd_pcm_stream_unlock_irq(substream);
    return 0;
}

static int snd_pcm_status_user(struct snd_pcm_substream *substream,
                   struct snd_pcm_status __user * _status)
{
    struct snd_pcm_status status;
    int res;
    
    memset(&status, 0, sizeof(status));
    res = snd_pcm_status(substream, &status);
    if (res < 0)
        return res;
    if (copy_to_user(_status, &status, sizeof(status)))
        return -EFAULT;
    return 0;
}

static int snd_pcm_channel_info(struct snd_pcm_substream *substream,
                struct snd_pcm_channel_info * info)
{
    struct snd_pcm_runtime *runtime;
    unsigned int channel;
    
    channel = info->channel;
    runtime = substream->runtime;
    snd_pcm_stream_lock_irq(substream);
    if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
        snd_pcm_stream_unlock_irq(substream);
        return -EBADFD;
    }
    snd_pcm_stream_unlock_irq(substream);
    if (channel >= runtime->channels)
        return -EINVAL;
    memset(info, 0, sizeof(*info));
    info->channel = channel;
    return substream->ops->ioctl(substream, SNDRV_PCM_IOCTL1_CHANNEL_INFO, info);
}

static int snd_pcm_channel_info_user(struct snd_pcm_substream *substream,
                     struct snd_pcm_channel_info __user * _info)
{
    struct snd_pcm_channel_info info;
    int res;
    
    if (copy_from_user(&info, _info, sizeof(info)))
        return -EFAULT;
    res = snd_pcm_channel_info(substream, &info);
    if (res < 0)
        return res;
    if (copy_to_user(_info, &info, sizeof(info)))
        return -EFAULT;
    return 0;
}

static void snd_pcm_trigger_tstamp(struct snd_pcm_substream *substream)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    if (runtime->trigger_master == NULL)
        return;
    if (runtime->trigger_master == substream) {
        snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
    } else {
        snd_pcm_trigger_tstamp(runtime->trigger_master);
        runtime->trigger_tstamp = runtime->trigger_master->runtime->trigger_tstamp;
    }
    runtime->trigger_master = NULL;
}

struct action_ops {
    int (*pre_action)(struct snd_pcm_substream *substream, int state);
    int (*do_action)(struct snd_pcm_substream *substream, int state);
    void (*undo_action)(struct snd_pcm_substream *substream, int state);
    void (*post_action)(struct snd_pcm_substream *substream, int state);
};

/*
 *  this functions is core for handling of linked stream
 *  Note: the stream state might be changed also on failure
 *  Note2: call with calling stream lock + link lock
 */
static int snd_pcm_action_group(struct action_ops *ops,
                struct snd_pcm_substream *substream,
                int state, int do_lock)
{
    struct snd_pcm_substream *s = NULL;
    struct snd_pcm_substream *s1;
    int res = 0;

    snd_pcm_group_for_each_entry(s, substream) {
        if (do_lock && s != substream)
            spin_lock_nested(&s->self_group.lock,
                     SINGLE_DEPTH_NESTING);
        res = ops->pre_action(s, state);
        if (res < 0)
            goto _unlock;
    }
    snd_pcm_group_for_each_entry(s, substream) {
        res = ops->do_action(s, state);
        if (res < 0) {
            if (ops->undo_action) {
                snd_pcm_group_for_each_entry(s1, substream) {
                    if (s1 == s) /* failed stream */
                        break;
                    ops->undo_action(s1, state);
                }
            }
            s = NULL; /* unlock all */
            goto _unlock;
        }
    }
    snd_pcm_group_for_each_entry(s, substream) {
        ops->post_action(s, state);
    }
 _unlock:
    if (do_lock) {
        /* unlock streams */
        snd_pcm_group_for_each_entry(s1, substream) {
            if (s1 != substream)
                spin_unlock(&s1->self_group.lock);
            if (s1 == s)    /* end */
                break;
        }
    }
    return res;
}

/*
 *  Note: call with stream lock
 */
static int snd_pcm_action_single(struct action_ops *ops,
                 struct snd_pcm_substream *substream,
                 int state)
{
    int res;
    
    res = ops->pre_action(substream, state);
    if (res < 0)
        return res;
    res = ops->do_action(substream, state);
    if (res == 0)
        ops->post_action(substream, state);
    else if (ops->undo_action)
        ops->undo_action(substream, state);
    return res;
}

/*
 *  Note: call with stream lock
 */
static int snd_pcm_action(struct action_ops *ops,
              struct snd_pcm_substream *substream,
              int state)
{
    int res;

    if (snd_pcm_stream_linked(substream)) {
        if (!spin_trylock(&substream->group->lock)) {
            spin_unlock(&substream->self_group.lock);
            spin_lock(&substream->group->lock);
            spin_lock(&substream->self_group.lock);
        }
        res = snd_pcm_action_group(ops, substream, state, 1);
        spin_unlock(&substream->group->lock);
    } else {
        res = snd_pcm_action_single(ops, substream, state);
    }
    return res;
}

/*
 *  Note: don't use any locks before
 */
static int snd_pcm_action_lock_irq(struct action_ops *ops,
                   struct snd_pcm_substream *substream,
                   int state)
{
    int res;

    read_lock_irq(&snd_pcm_link_rwlock);
    if (snd_pcm_stream_linked(substream)) {
        spin_lock(&substream->group->lock);
        spin_lock(&substream->self_group.lock);
        res = snd_pcm_action_group(ops, substream, state, 1);
        spin_unlock(&substream->self_group.lock);
        spin_unlock(&substream->group->lock);
    } else {
        spin_lock(&substream->self_group.lock);
        res = snd_pcm_action_single(ops, substream, state);
        spin_unlock(&substream->self_group.lock);
    }
    read_unlock_irq(&snd_pcm_link_rwlock);
    return res;
}

/*
 */
static int snd_pcm_action_nonatomic(struct action_ops *ops,
                    struct snd_pcm_substream *substream,
                    int state)
{
    int res;

    down_read(&snd_pcm_link_rwsem);
    if (snd_pcm_stream_linked(substream))
        res = snd_pcm_action_group(ops, substream, state, 0);
    else
        res = snd_pcm_action_single(ops, substream, state);
    up_read(&snd_pcm_link_rwsem);
    return res;
}

/*
 * start callbacks
 */
static int snd_pcm_pre_start(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    if (runtime->status->state != SNDRV_PCM_STATE_PREPARED)
        return -EBADFD;
    if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
        !snd_pcm_playback_data(substream))
        return -EPIPE;
    runtime->trigger_master = substream;
    return 0;
}

static int snd_pcm_do_start(struct snd_pcm_substream *substream, int state)
{
    if (substream->runtime->trigger_master != substream)
        return 0;
    return substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_START);
}

static void snd_pcm_undo_start(struct snd_pcm_substream *substream, int state)
{
    if (substream->runtime->trigger_master == substream)
        substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
}

static void snd_pcm_post_start(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    snd_pcm_trigger_tstamp(substream);
    runtime->hw_ptr_jiffies = jiffies;
    runtime->hw_ptr_buffer_jiffies = (runtime->buffer_size * HZ) / 
                                runtime->rate;
    runtime->status->state = state;
    if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
        runtime->silence_size > 0)
        snd_pcm_playback_silence(substream, ULONG_MAX);
    if (substream->timer)
        snd_timer_notify(substream->timer, SNDRV_TIMER_EVENT_MSTART,
                 &runtime->trigger_tstamp);
}

static struct action_ops snd_pcm_action_start = {
    .pre_action = snd_pcm_pre_start,
    .do_action = snd_pcm_do_start,
    .undo_action = snd_pcm_undo_start,
    .post_action = snd_pcm_post_start
};

int snd_pcm_start(struct snd_pcm_substream *substream)
{
    return snd_pcm_action(&snd_pcm_action_start, substream,
                  SNDRV_PCM_STATE_RUNNING);
}

/*
 * stop callbacks
 */
static int snd_pcm_pre_stop(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
        return -EBADFD;
    runtime->trigger_master = substream;
    return 0;
}

static int snd_pcm_do_stop(struct snd_pcm_substream *substream, int state)
{
    if (substream->runtime->trigger_master == substream &&
        snd_pcm_running(substream))
        substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
    return 0; /* unconditonally stop all substreams */
}

static void snd_pcm_post_stop(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    if (runtime->status->state != state) {
        snd_pcm_trigger_tstamp(substream);
        if (substream->timer)
            snd_timer_notify(substream->timer, SNDRV_TIMER_EVENT_MSTOP,
                     &runtime->trigger_tstamp);
        runtime->status->state = state;
    }
    wake_up(&runtime->sleep);
    wake_up(&runtime->tsleep);
}

static struct action_ops snd_pcm_action_stop = {
    .pre_action = snd_pcm_pre_stop,
    .do_action = snd_pcm_do_stop,
    .post_action = snd_pcm_post_stop
};

int snd_pcm_stop(struct snd_pcm_substream *substream, snd_pcm_state_t state)
{
    return snd_pcm_action(&snd_pcm_action_stop, substream, state);
}

EXPORT_SYMBOL(snd_pcm_stop);

int snd_pcm_drain_done(struct snd_pcm_substream *substream)
{
    return snd_pcm_action_single(&snd_pcm_action_stop, substream,
                     SNDRV_PCM_STATE_SETUP);
}

/*
 * pause callbacks
 */
static int snd_pcm_pre_pause(struct snd_pcm_substream *substream, int push)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    if (!(runtime->info & SNDRV_PCM_INFO_PAUSE))
        return -ENOSYS;
    if (push) {
        if (runtime->status->state != SNDRV_PCM_STATE_RUNNING)
            return -EBADFD;
    } else if (runtime->status->state != SNDRV_PCM_STATE_PAUSED)
        return -EBADFD;
    runtime->trigger_master = substream;
    return 0;
}

static int snd_pcm_do_pause(struct snd_pcm_substream *substream, int push)
{
    if (substream->runtime->trigger_master != substream)
        return 0;
    /* some drivers might use hw_ptr to recover from the pause -
       update the hw_ptr now */
    if (push)
        snd_pcm_update_hw_ptr(substream);
    /* The jiffies check in snd_pcm_update_hw_ptr*() is done by
     * a delta between the current jiffies, this gives a large enough
     * delta, effectively to skip the check once.
     */
    substream->runtime->hw_ptr_jiffies = jiffies - HZ * 1000;
    return substream->ops->trigger(substream,
                       push ? SNDRV_PCM_TRIGGER_PAUSE_PUSH :
                          SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
}

static void snd_pcm_undo_pause(struct snd_pcm_substream *substream, int push)
{
    if (substream->runtime->trigger_master == substream)
        substream->ops->trigger(substream,
                    push ? SNDRV_PCM_TRIGGER_PAUSE_RELEASE :
                    SNDRV_PCM_TRIGGER_PAUSE_PUSH);
}

static void snd_pcm_post_pause(struct snd_pcm_substream *substream, int push)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    snd_pcm_trigger_tstamp(substream);
    if (push) {
        runtime->status->state = SNDRV_PCM_STATE_PAUSED;
        if (substream->timer)
            snd_timer_notify(substream->timer,
                     SNDRV_TIMER_EVENT_MPAUSE,
                     &runtime->trigger_tstamp);
        wake_up(&runtime->sleep);
        wake_up(&runtime->tsleep);
    } else {
        runtime->status->state = SNDRV_PCM_STATE_RUNNING;
        if (substream->timer)
            snd_timer_notify(substream->timer,
                     SNDRV_TIMER_EVENT_MCONTINUE,
                     &runtime->trigger_tstamp);
    }
}

static struct action_ops snd_pcm_action_pause = {
    .pre_action = snd_pcm_pre_pause,
    .do_action = snd_pcm_do_pause,
    .undo_action = snd_pcm_undo_pause,
    .post_action = snd_pcm_post_pause
};

/*
 * Push/release the pause for all linked streams.
 */
static int snd_pcm_pause(struct snd_pcm_substream *substream, int push)
{
    return snd_pcm_action(&snd_pcm_action_pause, substream, push);
}

#ifdef CONFIG_PM
/* suspend */

static int snd_pcm_pre_suspend(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    if (runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
        return -EBUSY;
    runtime->trigger_master = substream;
    return 0;
}

static int snd_pcm_do_suspend(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    if (runtime->trigger_master != substream)
        return 0;
    if (! snd_pcm_running(substream))
        return 0;
    substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_SUSPEND);
    return 0; /* suspend unconditionally */
}

static void snd_pcm_post_suspend(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    snd_pcm_trigger_tstamp(substream);
    if (substream->timer)
        snd_timer_notify(substream->timer, SNDRV_TIMER_EVENT_MSUSPEND,
                 &runtime->trigger_tstamp);
    runtime->status->suspended_state = runtime->status->state;
    runtime->status->state = SNDRV_PCM_STATE_SUSPENDED;
    wake_up(&runtime->sleep);
    wake_up(&runtime->tsleep);
}

static struct action_ops snd_pcm_action_suspend = {
    .pre_action = snd_pcm_pre_suspend,
    .do_action = snd_pcm_do_suspend,
    .post_action = snd_pcm_post_suspend
};

int snd_pcm_suspend(struct snd_pcm_substream *substream)
{
    int err;
    unsigned long flags;

    if (! substream)
        return 0;

    snd_pcm_stream_lock_irqsave(substream, flags);
    err = snd_pcm_action(&snd_pcm_action_suspend, substream, 0);
    snd_pcm_stream_unlock_irqrestore(substream, flags);
    return err;
}

EXPORT_SYMBOL(snd_pcm_suspend);

int snd_pcm_suspend_all(struct snd_pcm *pcm)
{
    struct snd_pcm_substream *substream;
    int stream, err = 0;

    if (! pcm)
        return 0;

    for (stream = 0; stream < 2; stream++) {
        for (substream = pcm->streams[stream].substream;
             substream; substream = substream->next) {
            /* FIXME: the open/close code should lock this as well */
            if (substream->runtime == NULL)
                continue;
            err = snd_pcm_suspend(substream);
            if (err < 0 && err != -EBUSY)
                return err;
        }
    }
    return 0;
}

EXPORT_SYMBOL(snd_pcm_suspend_all);

/* resume */

static int snd_pcm_pre_resume(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    if (!(runtime->info & SNDRV_PCM_INFO_RESUME))
        return -ENOSYS;
    runtime->trigger_master = substream;
    return 0;
}

static int snd_pcm_do_resume(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    if (runtime->trigger_master != substream)
        return 0;
    /* DMA not running previously? */
    if (runtime->status->suspended_state != SNDRV_PCM_STATE_RUNNING &&
        (runtime->status->suspended_state != SNDRV_PCM_STATE_DRAINING ||
         substream->stream != SNDRV_PCM_STREAM_PLAYBACK))
        return 0;
    return substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_RESUME);
}

static void snd_pcm_undo_resume(struct snd_pcm_substream *substream, int state)
{
    if (substream->runtime->trigger_master == substream &&
        snd_pcm_running(substream))
        substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_SUSPEND);
}

static void snd_pcm_post_resume(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    snd_pcm_trigger_tstamp(substream);
    if (substream->timer)
        snd_timer_notify(substream->timer, SNDRV_TIMER_EVENT_MRESUME,
                 &runtime->trigger_tstamp);
    runtime->status->state = runtime->status->suspended_state;
}

static struct action_ops snd_pcm_action_resume = {
    .pre_action = snd_pcm_pre_resume,
    .do_action = snd_pcm_do_resume,
    .undo_action = snd_pcm_undo_resume,
    .post_action = snd_pcm_post_resume
};

static int snd_pcm_resume(struct snd_pcm_substream *substream)
{
    struct snd_card *card = substream->pcm->card;
    int res;

    snd_power_lock(card);
    if ((res = snd_power_wait(card, SNDRV_CTL_POWER_D0)) >= 0)
        res = snd_pcm_action_lock_irq(&snd_pcm_action_resume, substream, 0);
    snd_power_unlock(card);
    return res;
}

#else

static int snd_pcm_resume(struct snd_pcm_substream *substream)
{
    return -ENOSYS;
}

#endif /* CONFIG_PM */

/*
 * xrun ioctl
 *
 * Change the RUNNING stream(s) to XRUN state.
 */
static int snd_pcm_xrun(struct snd_pcm_substream *substream)
{
    struct snd_card *card = substream->pcm->card;
    struct snd_pcm_runtime *runtime = substream->runtime;
    int result;

    snd_power_lock(card);
    if (runtime->status->state == SNDRV_PCM_STATE_SUSPENDED) {
        result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
        if (result < 0)
            goto _unlock;
    }

    snd_pcm_stream_lock_irq(substream);
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_XRUN:
        result = 0; /* already there */
        break;
    case SNDRV_PCM_STATE_RUNNING:
        result = snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
        break;
    default:
        result = -EBADFD;
    }
    snd_pcm_stream_unlock_irq(substream);
 _unlock:
    snd_power_unlock(card);
    return result;
}

/*
 * reset ioctl
 */
static int snd_pcm_pre_reset(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_RUNNING:
    case SNDRV_PCM_STATE_PREPARED:
    case SNDRV_PCM_STATE_PAUSED:
    case SNDRV_PCM_STATE_SUSPENDED:
        return 0;
    default:
        return -EBADFD;
    }
}

static int snd_pcm_do_reset(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    int err = substream->ops->ioctl(substream, SNDRV_PCM_IOCTL1_RESET, NULL);
    if (err < 0)
        return err;
    runtime->hw_ptr_base = 0;
    runtime->hw_ptr_interrupt = runtime->status->hw_ptr -
        runtime->status->hw_ptr % runtime->period_size;
    runtime->silence_start = runtime->status->hw_ptr;
    runtime->silence_filled = 0;
    return 0;
}

static void snd_pcm_post_reset(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    runtime->control->appl_ptr = runtime->status->hw_ptr;
    if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
        runtime->silence_size > 0)
        snd_pcm_playback_silence(substream, ULONG_MAX);
}

static struct action_ops snd_pcm_action_reset = {
    .pre_action = snd_pcm_pre_reset,
    .do_action = snd_pcm_do_reset,
    .post_action = snd_pcm_post_reset
};

static int snd_pcm_reset(struct snd_pcm_substream *substream)
{
    return snd_pcm_action_nonatomic(&snd_pcm_action_reset, substream, 0);
}

/*
 * prepare ioctl
 */
/* we use the second argument for updating f_flags */
static int snd_pcm_pre_prepare(struct snd_pcm_substream *substream,
                   int f_flags)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    if (runtime->status->state == SNDRV_PCM_STATE_OPEN ||
        runtime->status->state == SNDRV_PCM_STATE_DISCONNECTED)
        return -EBADFD;
    if (snd_pcm_running(substream))
        return -EBUSY;
    substream->f_flags = f_flags;
    return 0;
}

static int snd_pcm_do_prepare(struct snd_pcm_substream *substream, int state)
{
    int err;
    err = substream->ops->prepare(substream);
    if (err < 0)
        return err;
    return snd_pcm_do_reset(substream, 0);
}

static void snd_pcm_post_prepare(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    runtime->control->appl_ptr = runtime->status->hw_ptr;
    snd_pcm_set_state(substream, SNDRV_PCM_STATE_PREPARED);
}

static struct action_ops snd_pcm_action_prepare = {
    .pre_action = snd_pcm_pre_prepare,
    .do_action = snd_pcm_do_prepare,
    .post_action = snd_pcm_post_prepare
};

static int snd_pcm_prepare(struct snd_pcm_substream *substream,
               struct file *file)
{
    int res;
    struct snd_card *card = substream->pcm->card;
    int f_flags;

    if (file)
        f_flags = file->f_flags;
    else
        f_flags = substream->f_flags;

    snd_power_lock(card);
    if ((res = snd_power_wait(card, SNDRV_CTL_POWER_D0)) >= 0)
        res = snd_pcm_action_nonatomic(&snd_pcm_action_prepare,
                           substream, f_flags);
    snd_power_unlock(card);
    return res;
}

/*
 * drain ioctl
 */

static int snd_pcm_pre_drain_init(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_OPEN:
    case SNDRV_PCM_STATE_DISCONNECTED:
    case SNDRV_PCM_STATE_SUSPENDED:
        return -EBADFD;
    }
    runtime->trigger_master = substream;
    return 0;
}

static int snd_pcm_do_drain_init(struct snd_pcm_substream *substream, int state)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
        switch (runtime->status->state) {
        case SNDRV_PCM_STATE_PREPARED:
            /* start playback stream if possible */
            if (! snd_pcm_playback_empty(substream)) {
                snd_pcm_do_start(substream, SNDRV_PCM_STATE_DRAINING);
                snd_pcm_post_start(substream, SNDRV_PCM_STATE_DRAINING);
            }
            break;
        case SNDRV_PCM_STATE_RUNNING:
            runtime->status->state = SNDRV_PCM_STATE_DRAINING;
            break;
        case SNDRV_PCM_STATE_XRUN:
            runtime->status->state = SNDRV_PCM_STATE_SETUP;
            break;
        default:
            break;
        }
    } else {
        /* stop running stream */
        if (runtime->status->state == SNDRV_PCM_STATE_RUNNING) {
            int new_state = snd_pcm_capture_avail(runtime) > 0 ?
                SNDRV_PCM_STATE_DRAINING : SNDRV_PCM_STATE_SETUP;
            snd_pcm_do_stop(substream, new_state);
            snd_pcm_post_stop(substream, new_state);
        }
    }
    return 0;
}

static void snd_pcm_post_drain_init(struct snd_pcm_substream *substream, int state)
{
}

static struct action_ops snd_pcm_action_drain_init = {
    .pre_action = snd_pcm_pre_drain_init,
    .do_action = snd_pcm_do_drain_init,
    .post_action = snd_pcm_post_drain_init
};

static int snd_pcm_drop(struct snd_pcm_substream *substream);

/*
 * Drain the stream(s).
 * When the substream is linked, sync until the draining of all playback streams
 * is finished.
 * After this call, all streams are supposed to be either SETUP or DRAINING
 * (capture only) state.
 */
static int snd_pcm_drain(struct snd_pcm_substream *substream,
             struct file *file)
{
    struct snd_card *card;
    struct snd_pcm_runtime *runtime;
    struct snd_pcm_substream *s;
    wait_queue_t wait;
    int result = 0;
    int nonblock = 0;

    card = substream->pcm->card;
    runtime = substream->runtime;

    if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
        return -EBADFD;

    snd_power_lock(card);
    if (runtime->status->state == SNDRV_PCM_STATE_SUSPENDED) {
        result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
        if (result < 0) {
            snd_power_unlock(card);
            return result;
        }
    }

    if (file) {
        if (file->f_flags & O_NONBLOCK)
            nonblock = 1;
    } else if (substream->f_flags & O_NONBLOCK)
        nonblock = 1;

    down_read(&snd_pcm_link_rwsem);
    snd_pcm_stream_lock_irq(substream);
    /* resume pause */
    if (runtime->status->state == SNDRV_PCM_STATE_PAUSED)
        snd_pcm_pause(substream, 0);

    /* pre-start/stop - all running streams are changed to DRAINING state */
    result = snd_pcm_action(&snd_pcm_action_drain_init, substream, 0);
    if (result < 0)
        goto unlock;
    /* in non-blocking, we don't wait in ioctl but let caller poll */
    if (nonblock) {
        result = -EAGAIN;
        goto unlock;
    }

    for (;;) {
        long tout;
        struct snd_pcm_runtime *to_check;
        if (signal_pending(current)) {
            result = -ERESTARTSYS;
            break;
        }
        /* find a substream to drain */
        to_check = NULL;
        snd_pcm_group_for_each_entry(s, substream) {
            if (s->stream != SNDRV_PCM_STREAM_PLAYBACK)
                continue;
            runtime = s->runtime;
            if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
                to_check = runtime;
                break;
            }
        }
        if (!to_check)
            break; /* all drained */
        init_waitqueue_entry(&wait, current);
        add_wait_queue(&to_check->sleep, &wait);
        snd_pcm_stream_unlock_irq(substream);
        up_read(&snd_pcm_link_rwsem);
        snd_power_unlock(card);
        if (runtime->no_period_wakeup)
            tout = MAX_SCHEDULE_TIMEOUT;
        else {
            tout = 10;
            if (runtime->rate) {
                long t = runtime->period_size * 2 / runtime->rate;
                tout = max(t, tout);
            }
            tout = msecs_to_jiffies(tout * 1000);
        }
        tout = schedule_timeout_interruptible(tout);
        snd_power_lock(card);
        down_read(&snd_pcm_link_rwsem);
        snd_pcm_stream_lock_irq(substream);
        remove_wait_queue(&to_check->sleep, &wait);
        if (card->shutdown) {
            result = -ENODEV;
            break;
        }
        if (tout == 0) {
            if (substream->runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
                result = -ESTRPIPE;
            else {
                snd_printd("playback drain error (DMA or IRQ trouble?)\n");
                snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
                result = -EIO;
            }
            break;
        }
    }

 unlock:
    snd_pcm_stream_unlock_irq(substream);
    up_read(&snd_pcm_link_rwsem);
    snd_power_unlock(card);

    return result;
}

/*
 * drop ioctl
 *
 * Immediately put all linked substreams into SETUP state.
 */
static int snd_pcm_drop(struct snd_pcm_substream *substream)
{
    struct snd_pcm_runtime *runtime;
    int result = 0;
    
    if (PCM_RUNTIME_CHECK(substream))
        return -ENXIO;
    runtime = substream->runtime;

    if (runtime->status->state == SNDRV_PCM_STATE_OPEN ||
        runtime->status->state == SNDRV_PCM_STATE_DISCONNECTED ||
        runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
        return -EBADFD;

    snd_pcm_stream_lock_irq(substream);
    /* resume pause */
    if (runtime->status->state == SNDRV_PCM_STATE_PAUSED)
        snd_pcm_pause(substream, 0);

    snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
    /* runtime->control->appl_ptr = runtime->status->hw_ptr; */
    snd_pcm_stream_unlock_irq(substream);

    return result;
}


/* WARNING: Don't forget to fput back the file */
static struct file *snd_pcm_file_fd(int fd, int *fput_needed)
{
    struct file *file;
    struct inode *inode;
    unsigned int minor;

    file = fget_light(fd, fput_needed);
    if (!file)
        return NULL;
    inode = file->f_path.dentry->d_inode;
    if (!S_ISCHR(inode->i_mode) ||
        imajor(inode) != snd_major) {
        fput_light(file, *fput_needed);
        return NULL;
    }
    minor = iminor(inode);
    if (!snd_lookup_minor_data(minor, SNDRV_DEVICE_TYPE_PCM_PLAYBACK) &&
        !snd_lookup_minor_data(minor, SNDRV_DEVICE_TYPE_PCM_CAPTURE)) {
        fput_light(file, *fput_needed);
        return NULL;
    }
    return file;
}

/*
 * PCM link handling
 */
static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
{
    int res = 0;
    struct file *file;
    struct snd_pcm_file *pcm_file;
    struct snd_pcm_substream *substream1;
    struct snd_pcm_group *group;
    int fput_needed;

    file = snd_pcm_file_fd(fd, &fput_needed);
    if (!file)
        return -EBADFD;
    pcm_file = file->private_data;
    substream1 = pcm_file->substream;
    group = kmalloc(sizeof(*group), GFP_KERNEL);
    if (!group) {
        res = -ENOMEM;
        goto _nolock;
    }
    down_write(&snd_pcm_link_rwsem);
    write_lock_irq(&snd_pcm_link_rwlock);
    if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN ||
        substream->runtime->status->state != substream1->runtime->status->state) {
        res = -EBADFD;
        goto _end;
    }
    if (snd_pcm_stream_linked(substream1)) {
        res = -EALREADY;
        goto _end;
    }
    if (!snd_pcm_stream_linked(substream)) {
        substream->group = group;
        spin_lock_init(&substream->group->lock);
        INIT_LIST_HEAD(&substream->group->substreams);
        list_add_tail(&substream->link_list, &substream->group->substreams);
        substream->group->count = 1;
    }
    list_add_tail(&substream1->link_list, &substream->group->substreams);
    substream->group->count++;
    substream1->group = substream->group;
 _end:
    write_unlock_irq(&snd_pcm_link_rwlock);
    up_write(&snd_pcm_link_rwsem);
 _nolock:
    snd_card_unref(substream1->pcm->card);
    fput_light(file, fput_needed);
    if (res < 0)
        kfree(group);
    return res;
}

static void relink_to_local(struct snd_pcm_substream *substream)
{
    substream->group = &substream->self_group;
    INIT_LIST_HEAD(&substream->self_group.substreams);
    list_add_tail(&substream->link_list, &substream->self_group.substreams);
}

static int snd_pcm_unlink(struct snd_pcm_substream *substream)
{
    struct snd_pcm_substream *s;
    int res = 0;

    down_write(&snd_pcm_link_rwsem);
    write_lock_irq(&snd_pcm_link_rwlock);
    if (!snd_pcm_stream_linked(substream)) {
        res = -EALREADY;
        goto _end;
    }
    list_del(&substream->link_list);
    substream->group->count--;
    if (substream->group->count == 1) { /* detach the last stream, too */
        snd_pcm_group_for_each_entry(s, substream) {
            relink_to_local(s);
            break;
        }
        kfree(substream->group);
    }
    relink_to_local(substream);
       _end:
    write_unlock_irq(&snd_pcm_link_rwlock);
    up_write(&snd_pcm_link_rwsem);
    return res;
}

/*
 * hw configurator
 */
static int snd_pcm_hw_rule_mul(struct snd_pcm_hw_params *params,
                   struct snd_pcm_hw_rule *rule)
{
    struct snd_interval t;
    snd_interval_mul(hw_param_interval_c(params, rule->deps[0]),
             hw_param_interval_c(params, rule->deps[1]), &t);
    return snd_interval_refine(hw_param_interval(params, rule->var), &t);
}

static int snd_pcm_hw_rule_div(struct snd_pcm_hw_params *params,
                   struct snd_pcm_hw_rule *rule)
{
    struct snd_interval t;
    snd_interval_div(hw_param_interval_c(params, rule->deps[0]),
             hw_param_interval_c(params, rule->deps[1]), &t);
    return snd_interval_refine(hw_param_interval(params, rule->var), &t);
}

static int snd_pcm_hw_rule_muldivk(struct snd_pcm_hw_params *params,
                   struct snd_pcm_hw_rule *rule)
{
    struct snd_interval t;
    snd_interval_muldivk(hw_param_interval_c(params, rule->deps[0]),
             hw_param_interval_c(params, rule->deps[1]),
             (unsigned long) rule->private, &t);
    return snd_interval_refine(hw_param_interval(params, rule->var), &t);
}

static int snd_pcm_hw_rule_mulkdiv(struct snd_pcm_hw_params *params,
                   struct snd_pcm_hw_rule *rule)
{
    struct snd_interval t;
    snd_interval_mulkdiv(hw_param_interval_c(params, rule->deps[0]),
             (unsigned long) rule->private,
             hw_param_interval_c(params, rule->deps[1]), &t);
    return snd_interval_refine(hw_param_interval(params, rule->var), &t);
}

static int snd_pcm_hw_rule_format(struct snd_pcm_hw_params *params,
                  struct snd_pcm_hw_rule *rule)
{
    unsigned int k;
    struct snd_interval *i = hw_param_interval(params, rule->deps[0]);
    struct snd_mask m;
    struct snd_mask *mask = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
    snd_mask_any(&m);
    for (k = 0; k <= SNDRV_PCM_FORMAT_LAST; ++k) {
        int bits;
        if (! snd_mask_test(mask, k))
            continue;
        bits = snd_pcm_format_physical_width(k);
        if (bits <= 0)
            continue; /* ignore invalid formats */
        if ((unsigned)bits < i->min || (unsigned)bits > i->max)
            snd_mask_reset(&m, k);
    }
    return snd_mask_refine(mask, &m);
}

static int snd_pcm_hw_rule_sample_bits(struct snd_pcm_hw_params *params,
                       struct snd_pcm_hw_rule *rule)
{
    struct snd_interval t;
    unsigned int k;
    t.min = UINT_MAX;
    t.max = 0;
    t.openmin = 0;
    t.openmax = 0;
    for (k = 0; k <= SNDRV_PCM_FORMAT_LAST; ++k) {
        int bits;
        if (! snd_mask_test(hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT), k))
            continue;
        bits = snd_pcm_format_physical_width(k);
        if (bits <= 0)
            continue; /* ignore invalid formats */
        if (t.min > (unsigned)bits)
            t.min = bits;
        if (t.max < (unsigned)bits)
            t.max = bits;
    }
    t.integer = 1;
    return snd_interval_refine(hw_param_interval(params, rule->var), &t);
}

#if SNDRV_PCM_RATE_5512 != 1 << 0 || SNDRV_PCM_RATE_192000 != 1 << 12
#error "Change this table"
#endif

static unsigned int rates[] = { 5512, 8000, 11025, 16000, 22050, 32000, 44100,
                                 48000, 64000, 88200, 96000, 176400, 192000 };

const struct snd_pcm_hw_constraint_list snd_pcm_known_rates = {
    .count = ARRAY_SIZE(rates),
    .list = rates,
};

static int snd_pcm_hw_rule_rate(struct snd_pcm_hw_params *params,
                struct snd_pcm_hw_rule *rule)
{
    struct snd_pcm_hardware *hw = rule->private;
    return snd_interval_list(hw_param_interval(params, rule->var),
                 snd_pcm_known_rates.count,
                 snd_pcm_known_rates.list, hw->rates);
}       

static int snd_pcm_hw_rule_buffer_bytes_max(struct snd_pcm_hw_params *params,
                        struct snd_pcm_hw_rule *rule)
{
    struct snd_interval t;
    struct snd_pcm_substream *substream = rule->private;
    t.min = 0;
    t.max = substream->buffer_bytes_max;
    t.openmin = 0;
    t.openmax = 0;
    t.integer = 1;
    return snd_interval_refine(hw_param_interval(params, rule->var), &t);
}       

int snd_pcm_hw_constraints_init(struct snd_pcm_substream *substream)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
    int k, err;

    for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++) {
        snd_mask_any(constrs_mask(constrs, k));
    }

    for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) {
        snd_interval_any(constrs_interval(constrs, k));
    }

    snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_CHANNELS));
    snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_BUFFER_SIZE));
    snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_BUFFER_BYTES));
    snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_SAMPLE_BITS));
    snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_FRAME_BITS));

    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
                   snd_pcm_hw_rule_format, NULL,
                   SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, 
                  snd_pcm_hw_rule_sample_bits, NULL,
                  SNDRV_PCM_HW_PARAM_FORMAT, 
                  SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, 
                  snd_pcm_hw_rule_div, NULL,
                  SNDRV_PCM_HW_PARAM_FRAME_BITS, SNDRV_PCM_HW_PARAM_CHANNELS, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS, 
                  snd_pcm_hw_rule_mul, NULL,
                  SNDRV_PCM_HW_PARAM_SAMPLE_BITS, SNDRV_PCM_HW_PARAM_CHANNELS, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS, 
                  snd_pcm_hw_rule_mulkdiv, (void*) 8,
                  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS, 
                  snd_pcm_hw_rule_mulkdiv, (void*) 8,
                  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS, 
                  snd_pcm_hw_rule_div, NULL,
                  SNDRV_PCM_HW_PARAM_FRAME_BITS, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE, 
                  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
                  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_PERIOD_TIME, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE, 
                  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
                  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_BUFFER_TIME, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIODS, 
                  snd_pcm_hw_rule_div, NULL,
                  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 
                  snd_pcm_hw_rule_div, NULL,
                  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_PERIODS, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 
                  snd_pcm_hw_rule_mulkdiv, (void*) 8,
                  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 
                  snd_pcm_hw_rule_muldivk, (void*) 1000000,
                  SNDRV_PCM_HW_PARAM_PERIOD_TIME, SNDRV_PCM_HW_PARAM_RATE, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, 
                  snd_pcm_hw_rule_mul, NULL,
                  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_PERIODS, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, 
                  snd_pcm_hw_rule_mulkdiv, (void*) 8,
                  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, 
                  snd_pcm_hw_rule_muldivk, (void*) 1000000,
                  SNDRV_PCM_HW_PARAM_BUFFER_TIME, SNDRV_PCM_HW_PARAM_RATE, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 
                  snd_pcm_hw_rule_muldivk, (void*) 8,
                  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 
                  snd_pcm_hw_rule_muldivk, (void*) 8,
                  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_TIME, 
                  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
                  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_RATE, -1);
    if (err < 0)
        return err;
    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_TIME, 
                  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
                  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_RATE, -1);
    if (err < 0)
        return err;
    return 0;
}

int snd_pcm_hw_constraints_complete(struct snd_pcm_substream *substream)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    struct snd_pcm_hardware *hw = &runtime->hw;
    int err;
    unsigned int mask = 0;

        if (hw->info & SNDRV_PCM_INFO_INTERLEAVED)
        mask |= 1 << SNDRV_PCM_ACCESS_RW_INTERLEAVED;
        if (hw->info & SNDRV_PCM_INFO_NONINTERLEAVED)
        mask |= 1 << SNDRV_PCM_ACCESS_RW_NONINTERLEAVED;
    if (hw->info & SNDRV_PCM_INFO_MMAP) {
        if (hw->info & SNDRV_PCM_INFO_INTERLEAVED)
            mask |= 1 << SNDRV_PCM_ACCESS_MMAP_INTERLEAVED;
        if (hw->info & SNDRV_PCM_INFO_NONINTERLEAVED)
            mask |= 1 << SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED;
        if (hw->info & SNDRV_PCM_INFO_COMPLEX)
            mask |= 1 << SNDRV_PCM_ACCESS_MMAP_COMPLEX;
    }
    err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_ACCESS, mask);
    if (err < 0)
        return err;

    err = snd_pcm_hw_constraint_mask64(runtime, SNDRV_PCM_HW_PARAM_FORMAT, hw->formats);
    if (err < 0)
        return err;

    err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_SUBFORMAT, 1 << SNDRV_PCM_SUBFORMAT_STD);
    if (err < 0)
        return err;

    err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_CHANNELS,
                       hw->channels_min, hw->channels_max);
    if (err < 0)
        return err;

    err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_RATE,
                       hw->rate_min, hw->rate_max);
    if (err < 0)
        return err;

    err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
                       hw->period_bytes_min, hw->period_bytes_max);
    if (err < 0)
        return err;

    err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIODS,
                       hw->periods_min, hw->periods_max);
    if (err < 0)
        return err;

    err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
                       hw->period_bytes_min, hw->buffer_bytes_max);
    if (err < 0)
        return err;

    err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 
                  snd_pcm_hw_rule_buffer_bytes_max, substream,
                  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, -1);
    if (err < 0)
        return err;

    /* FIXME: remove */
    if (runtime->dma_bytes) {
        err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 0, runtime->dma_bytes);
        if (err < 0)
            return -EINVAL;
    }

    if (!(hw->rates & (SNDRV_PCM_RATE_KNOT | SNDRV_PCM_RATE_CONTINUOUS))) {
        err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE, 
                      snd_pcm_hw_rule_rate, hw,
                      SNDRV_PCM_HW_PARAM_RATE, -1);
        if (err < 0)
            return err;
    }

    /* FIXME: this belong to lowlevel */
    snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIOD_SIZE);

    return 0;
}

static void pcm_release_private(struct snd_pcm_substream *substream)
{
    snd_pcm_unlink(substream);
}

void snd_pcm_release_substream(struct snd_pcm_substream *substream)
{
    substream->ref_count--;
    if (substream->ref_count > 0)
        return;

    snd_pcm_drop(substream);
    if (substream->hw_opened) {
        if (substream->ops->hw_free != NULL)
            substream->ops->hw_free(substream);
        substream->ops->close(substream);
        substream->hw_opened = 0;
    }
    if (pm_qos_request_active(&substream->latency_pm_qos_req))
        pm_qos_remove_request(&substream->latency_pm_qos_req);
    if (substream->pcm_release) {
        substream->pcm_release(substream);
        substream->pcm_release = NULL;
    }
    snd_pcm_detach_substream(substream);
}

EXPORT_SYMBOL(snd_pcm_release_substream);

int snd_pcm_open_substream(struct snd_pcm *pcm, int stream,
               struct file *file,
               struct snd_pcm_substream **rsubstream)
{
    struct snd_pcm_substream *substream;
    int err;

    err = snd_pcm_attach_substream(pcm, stream, file, &substream);
    if (err < 0)
        return err;
    if (substream->ref_count > 1) {
        *rsubstream = substream;
        return 0;
    }

    err = snd_pcm_hw_constraints_init(substream);
    if (err < 0) {
        snd_printd("snd_pcm_hw_constraints_init failed\n");
        goto error;
    }

    if ((err = substream->ops->open(substream)) < 0)
        goto error;

    substream->hw_opened = 1;

    err = snd_pcm_hw_constraints_complete(substream);
    if (err < 0) {
        snd_printd("snd_pcm_hw_constraints_complete failed\n");
        goto error;
    }

    *rsubstream = substream;
    return 0;

 error:
    snd_pcm_release_substream(substream);
    return err;
}

EXPORT_SYMBOL(snd_pcm_open_substream);

static int snd_pcm_open_file(struct file *file,
                 struct snd_pcm *pcm,
                 int stream)
{
    struct snd_pcm_file *pcm_file;
    struct snd_pcm_substream *substream;
    int err;

    err = snd_pcm_open_substream(pcm, stream, file, &substream);
    if (err < 0)
        return err;

    pcm_file = kzalloc(sizeof(*pcm_file), GFP_KERNEL);
    if (pcm_file == NULL) {
        snd_pcm_release_substream(substream);
        return -ENOMEM;
    }
    pcm_file->substream = substream;
    if (substream->ref_count == 1) {
        substream->file = pcm_file;
        substream->pcm_release = pcm_release_private;
    }
    file->private_data = pcm_file;

    return 0;
}

static int snd_pcm_playback_open(struct inode *inode, struct file *file)
{
    struct snd_pcm *pcm;
    int err = nonseekable_open(inode, file);
    if (err < 0)
        return err;
    pcm = snd_lookup_minor_data(iminor(inode),
                    SNDRV_DEVICE_TYPE_PCM_PLAYBACK);
    err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK);
    if (pcm)
        snd_card_unref(pcm->card);
    return err;
}

static int snd_pcm_capture_open(struct inode *inode, struct file *file)
{
    struct snd_pcm *pcm;
    int err = nonseekable_open(inode, file);
    if (err < 0)
        return err;
    pcm = snd_lookup_minor_data(iminor(inode),
                    SNDRV_DEVICE_TYPE_PCM_CAPTURE);
    err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE);
    if (pcm)
        snd_card_unref(pcm->card);
    return err;
}

static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream)
{
    int err;
    wait_queue_t wait;

    if (pcm == NULL) {
        err = -ENODEV;
        goto __error1;
    }
    err = snd_card_file_add(pcm->card, file);
    if (err < 0)
        goto __error1;
    if (!try_module_get(pcm->card->module)) {
        err = -EFAULT;
        goto __error2;
    }
    init_waitqueue_entry(&wait, current);
    add_wait_queue(&pcm->open_wait, &wait);
    mutex_lock(&pcm->open_mutex);
    while (1) {
        err = snd_pcm_open_file(file, pcm, stream);
        if (err >= 0)
            break;
        if (err == -EAGAIN) {
            if (file->f_flags & O_NONBLOCK) {
                err = -EBUSY;
                break;
            }
        } else
            break;
        set_current_state(TASK_INTERRUPTIBLE);
        mutex_unlock(&pcm->open_mutex);
        schedule();
        mutex_lock(&pcm->open_mutex);
        if (pcm->card->shutdown) {
            err = -ENODEV;
            break;
        }
        if (signal_pending(current)) {
            err = -ERESTARTSYS;
            break;
        }
    }
    remove_wait_queue(&pcm->open_wait, &wait);
    mutex_unlock(&pcm->open_mutex);
    if (err < 0)
        goto __error;
    return err;

      __error:
    module_put(pcm->card->module);
      __error2:
        snd_card_file_remove(pcm->card, file);
      __error1:
        return err;
}

static int snd_pcm_release(struct inode *inode, struct file *file)
{
    struct snd_pcm *pcm;
    struct snd_pcm_substream *substream;
    struct snd_pcm_file *pcm_file;

    pcm_file = file->private_data;
    substream = pcm_file->substream;
    if (snd_BUG_ON(!substream))
        return -ENXIO;
    pcm = substream->pcm;
    mutex_lock(&pcm->open_mutex);
    snd_pcm_release_substream(substream);
    kfree(pcm_file);
    mutex_unlock(&pcm->open_mutex);
    wake_up(&pcm->open_wait);
    module_put(pcm->card->module);
    snd_card_file_remove(pcm->card, file);
    return 0;
}

static snd_pcm_sframes_t snd_pcm_playback_rewind(struct snd_pcm_substream *substream,
                         snd_pcm_uframes_t frames)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    snd_pcm_sframes_t appl_ptr;
    snd_pcm_sframes_t ret;
    snd_pcm_sframes_t hw_avail;

    if (frames == 0)
        return 0;

    snd_pcm_stream_lock_irq(substream);
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_PREPARED:
        break;
    case SNDRV_PCM_STATE_DRAINING:
    case SNDRV_PCM_STATE_RUNNING:
        if (snd_pcm_update_hw_ptr(substream) >= 0)
            break;
        /* Fall through */
    case SNDRV_PCM_STATE_XRUN:
        ret = -EPIPE;
        goto __end;
    case SNDRV_PCM_STATE_SUSPENDED:
        ret = -ESTRPIPE;
        goto __end;
    default:
        ret = -EBADFD;
        goto __end;
    }

    hw_avail = snd_pcm_playback_hw_avail(runtime);
    if (hw_avail <= 0) {
        ret = 0;
        goto __end;
    }
    if (frames > (snd_pcm_uframes_t)hw_avail)
        frames = hw_avail;
    appl_ptr = runtime->control->appl_ptr - frames;
    if (appl_ptr < 0)
        appl_ptr += runtime->boundary;
    runtime->control->appl_ptr = appl_ptr;
    ret = frames;
 __end:
    snd_pcm_stream_unlock_irq(substream);
    return ret;
}

static snd_pcm_sframes_t snd_pcm_capture_rewind(struct snd_pcm_substream *substream,
                        snd_pcm_uframes_t frames)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    snd_pcm_sframes_t appl_ptr;
    snd_pcm_sframes_t ret;
    snd_pcm_sframes_t hw_avail;

    if (frames == 0)
        return 0;

    snd_pcm_stream_lock_irq(substream);
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_PREPARED:
    case SNDRV_PCM_STATE_DRAINING:
        break;
    case SNDRV_PCM_STATE_RUNNING:
        if (snd_pcm_update_hw_ptr(substream) >= 0)
            break;
        /* Fall through */
    case SNDRV_PCM_STATE_XRUN:
        ret = -EPIPE;
        goto __end;
    case SNDRV_PCM_STATE_SUSPENDED:
        ret = -ESTRPIPE;
        goto __end;
    default:
        ret = -EBADFD;
        goto __end;
    }

    hw_avail = snd_pcm_capture_hw_avail(runtime);
    if (hw_avail <= 0) {
        ret = 0;
        goto __end;
    }
    if (frames > (snd_pcm_uframes_t)hw_avail)
        frames = hw_avail;
    appl_ptr = runtime->control->appl_ptr - frames;
    if (appl_ptr < 0)
        appl_ptr += runtime->boundary;
    runtime->control->appl_ptr = appl_ptr;
    ret = frames;
 __end:
    snd_pcm_stream_unlock_irq(substream);
    return ret;
}

static snd_pcm_sframes_t snd_pcm_playback_forward(struct snd_pcm_substream *substream,
                          snd_pcm_uframes_t frames)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    snd_pcm_sframes_t appl_ptr;
    snd_pcm_sframes_t ret;
    snd_pcm_sframes_t avail;

    if (frames == 0)
        return 0;

    snd_pcm_stream_lock_irq(substream);
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_PREPARED:
    case SNDRV_PCM_STATE_PAUSED:
        break;
    case SNDRV_PCM_STATE_DRAINING:
    case SNDRV_PCM_STATE_RUNNING:
        if (snd_pcm_update_hw_ptr(substream) >= 0)
            break;
        /* Fall through */
    case SNDRV_PCM_STATE_XRUN:
        ret = -EPIPE;
        goto __end;
    case SNDRV_PCM_STATE_SUSPENDED:
        ret = -ESTRPIPE;
        goto __end;
    default:
        ret = -EBADFD;
        goto __end;
    }

    avail = snd_pcm_playback_avail(runtime);
    if (avail <= 0) {
        ret = 0;
        goto __end;
    }
    if (frames > (snd_pcm_uframes_t)avail)
        frames = avail;
    appl_ptr = runtime->control->appl_ptr + frames;
    if (appl_ptr >= (snd_pcm_sframes_t)runtime->boundary)
        appl_ptr -= runtime->boundary;
    runtime->control->appl_ptr = appl_ptr;
    ret = frames;
 __end:
    snd_pcm_stream_unlock_irq(substream);
    return ret;
}

static snd_pcm_sframes_t snd_pcm_capture_forward(struct snd_pcm_substream *substream,
                         snd_pcm_uframes_t frames)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    snd_pcm_sframes_t appl_ptr;
    snd_pcm_sframes_t ret;
    snd_pcm_sframes_t avail;

    if (frames == 0)
        return 0;

    snd_pcm_stream_lock_irq(substream);
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_PREPARED:
    case SNDRV_PCM_STATE_DRAINING:
    case SNDRV_PCM_STATE_PAUSED:
        break;
    case SNDRV_PCM_STATE_RUNNING:
        if (snd_pcm_update_hw_ptr(substream) >= 0)
            break;
        /* Fall through */
    case SNDRV_PCM_STATE_XRUN:
        ret = -EPIPE;
        goto __end;
    case SNDRV_PCM_STATE_SUSPENDED:
        ret = -ESTRPIPE;
        goto __end;
    default:
        ret = -EBADFD;
        goto __end;
    }

    avail = snd_pcm_capture_avail(runtime);
    if (avail <= 0) {
        ret = 0;
        goto __end;
    }
    if (frames > (snd_pcm_uframes_t)avail)
        frames = avail;
    appl_ptr = runtime->control->appl_ptr + frames;
    if (appl_ptr >= (snd_pcm_sframes_t)runtime->boundary)
        appl_ptr -= runtime->boundary;
    runtime->control->appl_ptr = appl_ptr;
    ret = frames;
 __end:
    snd_pcm_stream_unlock_irq(substream);
    return ret;
}

static int snd_pcm_hwsync(struct snd_pcm_substream *substream)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    int err;

    snd_pcm_stream_lock_irq(substream);
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_DRAINING:
        if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
            goto __badfd;
    case SNDRV_PCM_STATE_RUNNING:
        if ((err = snd_pcm_update_hw_ptr(substream)) < 0)
            break;
        /* Fall through */
    case SNDRV_PCM_STATE_PREPARED:
    case SNDRV_PCM_STATE_SUSPENDED:
        err = 0;
        break;
    case SNDRV_PCM_STATE_XRUN:
        err = -EPIPE;
        break;
    default:
          __badfd:
        err = -EBADFD;
        break;
    }
    snd_pcm_stream_unlock_irq(substream);
    return err;
}
        
static int snd_pcm_delay(struct snd_pcm_substream *substream,
             snd_pcm_sframes_t __user *res)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    int err;
    snd_pcm_sframes_t n = 0;

    snd_pcm_stream_lock_irq(substream);
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_DRAINING:
        if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
            goto __badfd;
    case SNDRV_PCM_STATE_RUNNING:
        if ((err = snd_pcm_update_hw_ptr(substream)) < 0)
            break;
        /* Fall through */
    case SNDRV_PCM_STATE_PREPARED:
    case SNDRV_PCM_STATE_SUSPENDED:
        err = 0;
        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
            n = snd_pcm_playback_hw_avail(runtime);
        else
            n = snd_pcm_capture_avail(runtime);
        n += runtime->delay;
        break;
    case SNDRV_PCM_STATE_XRUN:
        err = -EPIPE;
        break;
    default:
          __badfd:
        err = -EBADFD;
        break;
    }
    snd_pcm_stream_unlock_irq(substream);
    if (!err)
        if (put_user(n, res))
            err = -EFAULT;
    return err;
}
        
static int snd_pcm_sync_ptr(struct snd_pcm_substream *substream,
                struct snd_pcm_sync_ptr __user *_sync_ptr)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    struct snd_pcm_sync_ptr sync_ptr;
    volatile struct snd_pcm_mmap_status *status;
    volatile struct snd_pcm_mmap_control *control;
    int err;

    memset(&sync_ptr, 0, sizeof(sync_ptr));
    if (get_user(sync_ptr.flags, (unsigned __user *)&(_sync_ptr->flags)))
        return -EFAULT;
    if (copy_from_user(&sync_ptr.c.control, &(_sync_ptr->c.control), sizeof(struct snd_pcm_mmap_control)))
        return -EFAULT; 
    status = runtime->status;
    control = runtime->control;
    if (sync_ptr.flags & SNDRV_PCM_SYNC_PTR_HWSYNC) {
        err = snd_pcm_hwsync(substream);
        if (err < 0)
            return err;
    }
    snd_pcm_stream_lock_irq(substream);
    if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_APPL))
        control->appl_ptr = sync_ptr.c.control.appl_ptr;
    else
        sync_ptr.c.control.appl_ptr = control->appl_ptr;
    if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_AVAIL_MIN))
        control->avail_min = sync_ptr.c.control.avail_min;
    else
        sync_ptr.c.control.avail_min = control->avail_min;
    sync_ptr.s.status.state = status->state;
    sync_ptr.s.status.hw_ptr = status->hw_ptr;
    sync_ptr.s.status.tstamp = status->tstamp;
    sync_ptr.s.status.suspended_state = status->suspended_state;
    snd_pcm_stream_unlock_irq(substream);
    if (copy_to_user(_sync_ptr, &sync_ptr, sizeof(sync_ptr)))
        return -EFAULT;
    return 0;
}

static int snd_pcm_tstamp(struct snd_pcm_substream *substream, int __user *_arg)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    int arg;
    
    if (get_user(arg, _arg))
        return -EFAULT;
    if (arg < 0 || arg > SNDRV_PCM_TSTAMP_TYPE_LAST)
        return -EINVAL;
    runtime->tstamp_type = SNDRV_PCM_TSTAMP_TYPE_GETTIMEOFDAY;
    if (arg == SNDRV_PCM_TSTAMP_TYPE_MONOTONIC)
        runtime->tstamp_type = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC;
    return 0;
}
        
static int snd_pcm_common_ioctl1(struct file *file,
                 struct snd_pcm_substream *substream,
                 unsigned int cmd, void __user *arg)
{
    switch (cmd) {
    case SNDRV_PCM_IOCTL_PVERSION:
        return put_user(SNDRV_PCM_VERSION, (int __user *)arg) ? -EFAULT : 0;
    case SNDRV_PCM_IOCTL_INFO:
        return snd_pcm_info_user(substream, arg);
    case SNDRV_PCM_IOCTL_TSTAMP:    /* just for compatibility */
        return 0;
    case SNDRV_PCM_IOCTL_TTSTAMP:
        return snd_pcm_tstamp(substream, arg);
    case SNDRV_PCM_IOCTL_HW_REFINE:
        return snd_pcm_hw_refine_user(substream, arg);
    case SNDRV_PCM_IOCTL_HW_PARAMS:
        return snd_pcm_hw_params_user(substream, arg);
    case SNDRV_PCM_IOCTL_HW_FREE:
        return snd_pcm_hw_free(substream);
    case SNDRV_PCM_IOCTL_SW_PARAMS:
        return snd_pcm_sw_params_user(substream, arg);
    case SNDRV_PCM_IOCTL_STATUS:
        return snd_pcm_status_user(substream, arg);
    case SNDRV_PCM_IOCTL_CHANNEL_INFO:
        return snd_pcm_channel_info_user(substream, arg);
    case SNDRV_PCM_IOCTL_PREPARE:
        return snd_pcm_prepare(substream, file);
    case SNDRV_PCM_IOCTL_RESET:
        return snd_pcm_reset(substream);
    case SNDRV_PCM_IOCTL_START:
        return snd_pcm_action_lock_irq(&snd_pcm_action_start, substream, SNDRV_PCM_STATE_RUNNING);
    case SNDRV_PCM_IOCTL_LINK:
        return snd_pcm_link(substream, (int)(unsigned long) arg);
    case SNDRV_PCM_IOCTL_UNLINK:
        return snd_pcm_unlink(substream);
    case SNDRV_PCM_IOCTL_RESUME:
        return snd_pcm_resume(substream);
    case SNDRV_PCM_IOCTL_XRUN:
        return snd_pcm_xrun(substream);
    case SNDRV_PCM_IOCTL_HWSYNC:
        return snd_pcm_hwsync(substream);
    case SNDRV_PCM_IOCTL_DELAY:
        return snd_pcm_delay(substream, arg);
    case SNDRV_PCM_IOCTL_SYNC_PTR:
        return snd_pcm_sync_ptr(substream, arg);
#ifdef CONFIG_SND_SUPPORT_OLD_API
    case SNDRV_PCM_IOCTL_HW_REFINE_OLD:
        return snd_pcm_hw_refine_old_user(substream, arg);
    case SNDRV_PCM_IOCTL_HW_PARAMS_OLD:
        return snd_pcm_hw_params_old_user(substream, arg);
#endif
    case SNDRV_PCM_IOCTL_DRAIN:
        return snd_pcm_drain(substream, file);
    case SNDRV_PCM_IOCTL_DROP:
        return snd_pcm_drop(substream);
    case SNDRV_PCM_IOCTL_PAUSE:
    {
        int res;
        snd_pcm_stream_lock_irq(substream);
        res = snd_pcm_pause(substream, (int)(unsigned long)arg);
        snd_pcm_stream_unlock_irq(substream);
        return res;
    }
    }
    snd_printd("unknown ioctl = 0x%x\n", cmd);
    return -ENOTTY;
}

static int snd_pcm_playback_ioctl1(struct file *file,
                   struct snd_pcm_substream *substream,
                   unsigned int cmd, void __user *arg)
{
    if (snd_BUG_ON(!substream))
        return -ENXIO;
    if (snd_BUG_ON(substream->stream != SNDRV_PCM_STREAM_PLAYBACK))
        return -EINVAL;
    switch (cmd) {
    case SNDRV_PCM_IOCTL_WRITEI_FRAMES:
    {
        struct snd_xferi xferi;
        struct snd_xferi __user *_xferi = arg;
        struct snd_pcm_runtime *runtime = substream->runtime;
        snd_pcm_sframes_t result;
        if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
            return -EBADFD;
        if (put_user(0, &_xferi->result))
            return -EFAULT;
        if (copy_from_user(&xferi, _xferi, sizeof(xferi)))
            return -EFAULT;
        result = snd_pcm_lib_write(substream, xferi.buf, xferi.frames);
        __put_user(result, &_xferi->result);
        return result < 0 ? result : 0;
    }
    case SNDRV_PCM_IOCTL_WRITEN_FRAMES:
    {
        struct snd_xfern xfern;
        struct snd_xfern __user *_xfern = arg;
        struct snd_pcm_runtime *runtime = substream->runtime;
        void __user **bufs;
        snd_pcm_sframes_t result;
        if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
            return -EBADFD;
        if (runtime->channels > 128)
            return -EINVAL;
        if (put_user(0, &_xfern->result))
            return -EFAULT;
        if (copy_from_user(&xfern, _xfern, sizeof(xfern)))
            return -EFAULT;

        bufs = memdup_user(xfern.bufs,
                   sizeof(void *) * runtime->channels);
        if (IS_ERR(bufs))
            return PTR_ERR(bufs);
        result = snd_pcm_lib_writev(substream, bufs, xfern.frames);
        kfree(bufs);
        __put_user(result, &_xfern->result);
        return result < 0 ? result : 0;
    }
    case SNDRV_PCM_IOCTL_REWIND:
    {
        snd_pcm_uframes_t frames;
        snd_pcm_uframes_t __user *_frames = arg;
        snd_pcm_sframes_t result;
        if (get_user(frames, _frames))
            return -EFAULT;
        if (put_user(0, _frames))
            return -EFAULT;
        result = snd_pcm_playback_rewind(substream, frames);
        __put_user(result, _frames);
        return result < 0 ? result : 0;
    }
    case SNDRV_PCM_IOCTL_FORWARD:
    {
        snd_pcm_uframes_t frames;
        snd_pcm_uframes_t __user *_frames = arg;
        snd_pcm_sframes_t result;
        if (get_user(frames, _frames))
            return -EFAULT;
        if (put_user(0, _frames))
            return -EFAULT;
        result = snd_pcm_playback_forward(substream, frames);
        __put_user(result, _frames);
        return result < 0 ? result : 0;
    }
    }
    return snd_pcm_common_ioctl1(file, substream, cmd, arg);
}

static int snd_pcm_capture_ioctl1(struct file *file,
                  struct snd_pcm_substream *substream,
                  unsigned int cmd, void __user *arg)
{
    if (snd_BUG_ON(!substream))
        return -ENXIO;
    if (snd_BUG_ON(substream->stream != SNDRV_PCM_STREAM_CAPTURE))
        return -EINVAL;
    switch (cmd) {
    case SNDRV_PCM_IOCTL_READI_FRAMES:
    {
        struct snd_xferi xferi;
        struct snd_xferi __user *_xferi = arg;
        struct snd_pcm_runtime *runtime = substream->runtime;
        snd_pcm_sframes_t result;
        if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
            return -EBADFD;
        if (put_user(0, &_xferi->result))
            return -EFAULT;
        if (copy_from_user(&xferi, _xferi, sizeof(xferi)))
            return -EFAULT;
        result = snd_pcm_lib_read(substream, xferi.buf, xferi.frames);
        __put_user(result, &_xferi->result);
        return result < 0 ? result : 0;
    }
    case SNDRV_PCM_IOCTL_READN_FRAMES:
    {
        struct snd_xfern xfern;
        struct snd_xfern __user *_xfern = arg;
        struct snd_pcm_runtime *runtime = substream->runtime;
        void *bufs;
        snd_pcm_sframes_t result;
        if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
            return -EBADFD;
        if (runtime->channels > 128)
            return -EINVAL;
        if (put_user(0, &_xfern->result))
            return -EFAULT;
        if (copy_from_user(&xfern, _xfern, sizeof(xfern)))
            return -EFAULT;

        bufs = memdup_user(xfern.bufs,
                   sizeof(void *) * runtime->channels);
        if (IS_ERR(bufs))
            return PTR_ERR(bufs);
        result = snd_pcm_lib_readv(substream, bufs, xfern.frames);
        kfree(bufs);
        __put_user(result, &_xfern->result);
        return result < 0 ? result : 0;
    }
    case SNDRV_PCM_IOCTL_REWIND:
    {
        snd_pcm_uframes_t frames;
        snd_pcm_uframes_t __user *_frames = arg;
        snd_pcm_sframes_t result;
        if (get_user(frames, _frames))
            return -EFAULT;
        if (put_user(0, _frames))
            return -EFAULT;
        result = snd_pcm_capture_rewind(substream, frames);
        __put_user(result, _frames);
        return result < 0 ? result : 0;
    }
    case SNDRV_PCM_IOCTL_FORWARD:
    {
        snd_pcm_uframes_t frames;
        snd_pcm_uframes_t __user *_frames = arg;
        snd_pcm_sframes_t result;
        if (get_user(frames, _frames))
            return -EFAULT;
        if (put_user(0, _frames))
            return -EFAULT;
        result = snd_pcm_capture_forward(substream, frames);
        __put_user(result, _frames);
        return result < 0 ? result : 0;
    }
    }
    return snd_pcm_common_ioctl1(file, substream, cmd, arg);
}

static long snd_pcm_playback_ioctl(struct file *file, unsigned int cmd,
                   unsigned long arg)
{
    struct snd_pcm_file *pcm_file;

    pcm_file = file->private_data;

    if (((cmd >> 8) & 0xff) != 'A')
        return -ENOTTY;

    return snd_pcm_playback_ioctl1(file, pcm_file->substream, cmd,
                       (void __user *)arg);
}

static long snd_pcm_capture_ioctl(struct file *file, unsigned int cmd,
                  unsigned long arg)
{
    struct snd_pcm_file *pcm_file;

    pcm_file = file->private_data;

    if (((cmd >> 8) & 0xff) != 'A')
        return -ENOTTY;

    return snd_pcm_capture_ioctl1(file, pcm_file->substream, cmd,
                      (void __user *)arg);
}

int snd_pcm_kernel_ioctl(struct snd_pcm_substream *substream,
             unsigned int cmd, void *arg)
{
    mm_segment_t fs;
    int result;
    
    fs = snd_enter_user();
    switch (substream->stream) {
    case SNDRV_PCM_STREAM_PLAYBACK:
        result = snd_pcm_playback_ioctl1(NULL, substream, cmd,
                         (void __user *)arg);
        break;
    case SNDRV_PCM_STREAM_CAPTURE:
        result = snd_pcm_capture_ioctl1(NULL, substream, cmd,
                        (void __user *)arg);
        break;
    default:
        result = -EINVAL;
        break;
    }
    snd_leave_user(fs);
    return result;
}

EXPORT_SYMBOL(snd_pcm_kernel_ioctl);

static ssize_t snd_pcm_read(struct file *file, char __user *buf, size_t count,
                loff_t * offset)
{
    struct snd_pcm_file *pcm_file;
    struct snd_pcm_substream *substream;
    struct snd_pcm_runtime *runtime;
    snd_pcm_sframes_t result;

    pcm_file = file->private_data;
    substream = pcm_file->substream;
    if (PCM_RUNTIME_CHECK(substream))
        return -ENXIO;
    runtime = substream->runtime;
    if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
        return -EBADFD;
    if (!frame_aligned(runtime, count))
        return -EINVAL;
    count = bytes_to_frames(runtime, count);
    result = snd_pcm_lib_read(substream, buf, count);
    if (result > 0)
        result = frames_to_bytes(runtime, result);
    return result;
}

static ssize_t snd_pcm_write(struct file *file, const char __user *buf,
                 size_t count, loff_t * offset)
{
    struct snd_pcm_file *pcm_file;
    struct snd_pcm_substream *substream;
    struct snd_pcm_runtime *runtime;
    snd_pcm_sframes_t result;

    pcm_file = file->private_data;
    substream = pcm_file->substream;
    if (PCM_RUNTIME_CHECK(substream))
        return -ENXIO;
    runtime = substream->runtime;
    if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
        return -EBADFD;
    if (!frame_aligned(runtime, count))
        return -EINVAL;
    count = bytes_to_frames(runtime, count);
    result = snd_pcm_lib_write(substream, buf, count);
    if (result > 0)
        result = frames_to_bytes(runtime, result);
    return result;
}

static ssize_t snd_pcm_aio_read(struct kiocb *iocb, const struct iovec *iov,
                 unsigned long nr_segs, loff_t pos)

{
    struct snd_pcm_file *pcm_file;
    struct snd_pcm_substream *substream;
    struct snd_pcm_runtime *runtime;
    snd_pcm_sframes_t result;
    unsigned long i;
    void __user **bufs;
    snd_pcm_uframes_t frames;

    pcm_file = iocb->ki_filp->private_data;
    substream = pcm_file->substream;
    if (PCM_RUNTIME_CHECK(substream))
        return -ENXIO;
    runtime = substream->runtime;
    if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
        return -EBADFD;
    if (nr_segs > 1024 || nr_segs != runtime->channels)
        return -EINVAL;
    if (!frame_aligned(runtime, iov->iov_len))
        return -EINVAL;
    frames = bytes_to_samples(runtime, iov->iov_len);
    bufs = kmalloc(sizeof(void *) * nr_segs, GFP_KERNEL);
    if (bufs == NULL)
        return -ENOMEM;
    for (i = 0; i < nr_segs; ++i)
        bufs[i] = iov[i].iov_base;
    result = snd_pcm_lib_readv(substream, bufs, frames);
    if (result > 0)
        result = frames_to_bytes(runtime, result);
    kfree(bufs);
    return result;
}

static ssize_t snd_pcm_aio_write(struct kiocb *iocb, const struct iovec *iov,
                  unsigned long nr_segs, loff_t pos)
{
    struct snd_pcm_file *pcm_file;
    struct snd_pcm_substream *substream;
    struct snd_pcm_runtime *runtime;
    snd_pcm_sframes_t result;
    unsigned long i;
    void __user **bufs;
    snd_pcm_uframes_t frames;

    pcm_file = iocb->ki_filp->private_data;
    substream = pcm_file->substream;
    if (PCM_RUNTIME_CHECK(substream))
        return -ENXIO;
    runtime = substream->runtime;
    if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
        return -EBADFD;
    if (nr_segs > 128 || nr_segs != runtime->channels ||
        !frame_aligned(runtime, iov->iov_len))
        return -EINVAL;
    frames = bytes_to_samples(runtime, iov->iov_len);
    bufs = kmalloc(sizeof(void *) * nr_segs, GFP_KERNEL);
    if (bufs == NULL)
        return -ENOMEM;
    for (i = 0; i < nr_segs; ++i)
        bufs[i] = iov[i].iov_base;
    result = snd_pcm_lib_writev(substream, bufs, frames);
    if (result > 0)
        result = frames_to_bytes(runtime, result);
    kfree(bufs);
    return result;
}

static unsigned int snd_pcm_playback_poll(struct file *file, poll_table * wait)
{
    struct snd_pcm_file *pcm_file;
    struct snd_pcm_substream *substream;
    struct snd_pcm_runtime *runtime;
        unsigned int mask;
    snd_pcm_uframes_t avail;

    pcm_file = file->private_data;

    substream = pcm_file->substream;
    if (PCM_RUNTIME_CHECK(substream))
        return -ENXIO;
    runtime = substream->runtime;

    poll_wait(file, &runtime->sleep, wait);

    snd_pcm_stream_lock_irq(substream);
    avail = snd_pcm_playback_avail(runtime);
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_RUNNING:
    case SNDRV_PCM_STATE_PREPARED:
    case SNDRV_PCM_STATE_PAUSED:
        if (avail >= runtime->control->avail_min) {
            mask = POLLOUT | POLLWRNORM;
            break;
        }
        /* Fall through */
    case SNDRV_PCM_STATE_DRAINING:
        mask = 0;
        break;
    default:
        mask = POLLOUT | POLLWRNORM | POLLERR;
        break;
    }
    snd_pcm_stream_unlock_irq(substream);
    return mask;
}

static unsigned int snd_pcm_capture_poll(struct file *file, poll_table * wait)
{
    struct snd_pcm_file *pcm_file;
    struct snd_pcm_substream *substream;
    struct snd_pcm_runtime *runtime;
        unsigned int mask;
    snd_pcm_uframes_t avail;

    pcm_file = file->private_data;

    substream = pcm_file->substream;
    if (PCM_RUNTIME_CHECK(substream))
        return -ENXIO;
    runtime = substream->runtime;

    poll_wait(file, &runtime->sleep, wait);

    snd_pcm_stream_lock_irq(substream);
    avail = snd_pcm_capture_avail(runtime);
    switch (runtime->status->state) {
    case SNDRV_PCM_STATE_RUNNING:
    case SNDRV_PCM_STATE_PREPARED:
    case SNDRV_PCM_STATE_PAUSED:
        if (avail >= runtime->control->avail_min) {
            mask = POLLIN | POLLRDNORM;
            break;
        }
        mask = 0;
        break;
    case SNDRV_PCM_STATE_DRAINING:
        if (avail > 0) {
            mask = POLLIN | POLLRDNORM;
            break;
        }
        /* Fall through */
    default:
        mask = POLLIN | POLLRDNORM | POLLERR;
        break;
    }
    snd_pcm_stream_unlock_irq(substream);
    return mask;
}

/*
 * mmap support
 */

/*
 * Only on coherent architectures, we can mmap the status and the control records
 * for effcient data transfer.  On others, we have to use HWSYNC ioctl...
 */
#if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_ALPHA)
/*
 * mmap status record
 */
static int snd_pcm_mmap_status_fault(struct vm_area_struct *area,
                        struct vm_fault *vmf)
{
    struct snd_pcm_substream *substream = area->vm_private_data;
    struct snd_pcm_runtime *runtime;
    
    if (substream == NULL)
        return VM_FAULT_SIGBUS;
    runtime = substream->runtime;
    vmf->page = virt_to_page(runtime->status);
    get_page(vmf->page);
    return 0;
}

static const struct vm_operations_struct snd_pcm_vm_ops_status =
{
    .fault =    snd_pcm_mmap_status_fault,
};

static int snd_pcm_mmap_status(struct snd_pcm_substream *substream, struct file *file,
                   struct vm_area_struct *area)
{
    long size;
    if (!(area->vm_flags & VM_READ))
        return -EINVAL;
    size = area->vm_end - area->vm_start;
    if (size != PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)))
        return -EINVAL;
    area->vm_ops = &snd_pcm_vm_ops_status;
    area->vm_private_data = substream;
    area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
    return 0;
}

/*
 * mmap control record
 */
static int snd_pcm_mmap_control_fault(struct vm_area_struct *area,
                        struct vm_fault *vmf)
{
    struct snd_pcm_substream *substream = area->vm_private_data;
    struct snd_pcm_runtime *runtime;
    
    if (substream == NULL)
        return VM_FAULT_SIGBUS;
    runtime = substream->runtime;
    vmf->page = virt_to_page(runtime->control);
    get_page(vmf->page);
    return 0;
}

static const struct vm_operations_struct snd_pcm_vm_ops_control =
{
    .fault =    snd_pcm_mmap_control_fault,
};

static int snd_pcm_mmap_control(struct snd_pcm_substream *substream, struct file *file,
                struct vm_area_struct *area)
{
    long size;
    if (!(area->vm_flags & VM_READ))
        return -EINVAL;
    size = area->vm_end - area->vm_start;
    if (size != PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)))
        return -EINVAL;
    area->vm_ops = &snd_pcm_vm_ops_control;
    area->vm_private_data = substream;
    area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
    return 0;
}
#else /* ! coherent mmap */
/*
 * don't support mmap for status and control records.
 */
static int snd_pcm_mmap_status(struct snd_pcm_substream *substream, struct file *file,
                   struct vm_area_struct *area)
{
    return -ENXIO;
}
static int snd_pcm_mmap_control(struct snd_pcm_substream *substream, struct file *file,
                struct vm_area_struct *area)
{
    return -ENXIO;
}
#endif /* coherent mmap */

static inline struct page *
snd_pcm_default_page_ops(struct snd_pcm_substream *substream, unsigned long ofs)
{
    void *vaddr = substream->runtime->dma_area + ofs;
#if defined(CONFIG_MIPS) && defined(CONFIG_DMA_NONCOHERENT)
    if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV)
        return virt_to_page(CAC_ADDR(vaddr));
#endif
#if defined(CONFIG_PPC32) && defined(CONFIG_NOT_COHERENT_CACHE)
    if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV) {
        dma_addr_t addr = substream->runtime->dma_addr + ofs;
        addr -= get_dma_offset(substream->dma_buffer.dev.dev);
        /* assume dma_handle set via pfn_to_phys() in
         * mm/dma-noncoherent.c
         */
        return pfn_to_page(addr >> PAGE_SHIFT);
    }
#endif
    return virt_to_page(vaddr);
}

/*
 * fault callback for mmapping a RAM page
 */
static int snd_pcm_mmap_data_fault(struct vm_area_struct *area,
                        struct vm_fault *vmf)
{
    struct snd_pcm_substream *substream = area->vm_private_data;
    struct snd_pcm_runtime *runtime;
    unsigned long offset;
    struct page * page;
    size_t dma_bytes;
    
    if (substream == NULL)
        return VM_FAULT_SIGBUS;
    runtime = substream->runtime;
    offset = vmf->pgoff << PAGE_SHIFT;
    dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
    if (offset > dma_bytes - PAGE_SIZE)
        return VM_FAULT_SIGBUS;
    if (substream->ops->page)
        page = substream->ops->page(substream, offset);
    else
        page = snd_pcm_default_page_ops(substream, offset);
    if (!page)
        return VM_FAULT_SIGBUS;
    get_page(page);
    vmf->page = page;
    return 0;
}

static const struct vm_operations_struct snd_pcm_vm_ops_data = {
    .open =     snd_pcm_mmap_data_open,
    .close =    snd_pcm_mmap_data_close,
};

static const struct vm_operations_struct snd_pcm_vm_ops_data_fault = {
    .open =     snd_pcm_mmap_data_open,
    .close =    snd_pcm_mmap_data_close,
    .fault =    snd_pcm_mmap_data_fault,
};

#ifndef ARCH_HAS_DMA_MMAP_COHERENT
/* This should be defined / handled globally! */
#ifdef CONFIG_ARM
#define ARCH_HAS_DMA_MMAP_COHERENT
#endif
#endif

/*
 * mmap the DMA buffer on RAM
 */
int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
                 struct vm_area_struct *area)
{
    area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
#ifdef ARCH_HAS_DMA_MMAP_COHERENT
    if (!substream->ops->page &&
        substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV)
        return dma_mmap_coherent(substream->dma_buffer.dev.dev,
                     area,
                     substream->runtime->dma_area,
                     substream->runtime->dma_addr,
                     area->vm_end - area->vm_start);
#elif defined(CONFIG_MIPS) && defined(CONFIG_DMA_NONCOHERENT)
    if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV &&
        !plat_device_is_coherent(substream->dma_buffer.dev.dev))
        area->vm_page_prot = pgprot_noncached(area->vm_page_prot);
#endif /* ARCH_HAS_DMA_MMAP_COHERENT */
    /* mmap with fault handler */
    area->vm_ops = &snd_pcm_vm_ops_data_fault;
    return 0;
}
EXPORT_SYMBOL_GPL(snd_pcm_lib_default_mmap);

/*
 * mmap the DMA buffer on I/O memory area
 */
#if SNDRV_PCM_INFO_MMAP_IOMEM
int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream,
               struct vm_area_struct *area)
{
    long size;
    unsigned long offset;

    area->vm_page_prot = pgprot_noncached(area->vm_page_prot);
    area->vm_flags |= VM_IO;
    size = area->vm_end - area->vm_start;
    offset = area->vm_pgoff << PAGE_SHIFT;
    if (io_remap_pfn_range(area, area->vm_start,
                (substream->runtime->dma_addr + offset) >> PAGE_SHIFT,
                size, area->vm_page_prot))
        return -EAGAIN;
    return 0;
}

EXPORT_SYMBOL(snd_pcm_lib_mmap_iomem);
#endif /* SNDRV_PCM_INFO_MMAP */

/*
 * mmap DMA buffer
 */
int snd_pcm_mmap_data(struct snd_pcm_substream *substream, struct file *file,
              struct vm_area_struct *area)
{
    struct snd_pcm_runtime *runtime;
    long size;
    unsigned long offset;
    size_t dma_bytes;
    int err;

    if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
        if (!(area->vm_flags & (VM_WRITE|VM_READ)))
            return -EINVAL;
    } else {
        if (!(area->vm_flags & VM_READ))
            return -EINVAL;
    }
    runtime = substream->runtime;
    if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
        return -EBADFD;
    if (!(runtime->info & SNDRV_PCM_INFO_MMAP))
        return -ENXIO;
    if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
        runtime->access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
        return -EINVAL;
    size = area->vm_end - area->vm_start;
    offset = area->vm_pgoff << PAGE_SHIFT;
    dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
    if ((size_t)size > dma_bytes)
        return -EINVAL;
    if (offset > dma_bytes - size)
        return -EINVAL;

    area->vm_ops = &snd_pcm_vm_ops_data;
    area->vm_private_data = substream;
    if (substream->ops->mmap)
        err = substream->ops->mmap(substream, area);
    else
        err = snd_pcm_lib_default_mmap(substream, area);
    if (!err)
        atomic_inc(&substream->mmap_count);
    return err;
}

EXPORT_SYMBOL(snd_pcm_mmap_data);

static int snd_pcm_mmap(struct file *file, struct vm_area_struct *area)
{
    struct snd_pcm_file * pcm_file;
    struct snd_pcm_substream *substream;    
    unsigned long offset;
    
    pcm_file = file->private_data;
    substream = pcm_file->substream;
    if (PCM_RUNTIME_CHECK(substream))
        return -ENXIO;

    offset = area->vm_pgoff << PAGE_SHIFT;
    switch (offset) {
    case SNDRV_PCM_MMAP_OFFSET_STATUS:
        if (pcm_file->no_compat_mmap)
            return -ENXIO;
        return snd_pcm_mmap_status(substream, file, area);
    case SNDRV_PCM_MMAP_OFFSET_CONTROL:
        if (pcm_file->no_compat_mmap)
            return -ENXIO;
        return snd_pcm_mmap_control(substream, file, area);
    default:
        return snd_pcm_mmap_data(substream, file, area);
    }
    return 0;
}

static int snd_pcm_fasync(int fd, struct file * file, int on)
{
    struct snd_pcm_file * pcm_file;
    struct snd_pcm_substream *substream;
    struct snd_pcm_runtime *runtime;

    pcm_file = file->private_data;
    substream = pcm_file->substream;
    if (PCM_RUNTIME_CHECK(substream))
        return -ENXIO;
    runtime = substream->runtime;
    return fasync_helper(fd, file, on, &runtime->fasync);
}

/*
 * ioctl32 compat
 */
#ifdef CONFIG_COMPAT
#include "pcm_compat.c"
#else
#define snd_pcm_ioctl_compat    NULL
#endif

/*
 *  To be removed helpers to keep binary compatibility
 */

#ifdef CONFIG_SND_SUPPORT_OLD_API
#define __OLD_TO_NEW_MASK(x) ((x&7)|((x&0x07fffff8)<<5))
#define __NEW_TO_OLD_MASK(x) ((x&7)|((x&0xffffff00)>>5))

static void snd_pcm_hw_convert_from_old_params(struct snd_pcm_hw_params *params,
                           struct snd_pcm_hw_params_old *oparams)
{
    unsigned int i;

    memset(params, 0, sizeof(*params));
    params->flags = oparams->flags;
    for (i = 0; i < ARRAY_SIZE(oparams->masks); i++)
        params->masks[i].bits[0] = oparams->masks[i];
    memcpy(params->intervals, oparams->intervals, sizeof(oparams->intervals));
    params->rmask = __OLD_TO_NEW_MASK(oparams->rmask);
    params->cmask = __OLD_TO_NEW_MASK(oparams->cmask);
    params->info = oparams->info;
    params->msbits = oparams->msbits;
    params->rate_num = oparams->rate_num;
    params->rate_den = oparams->rate_den;
    params->fifo_size = oparams->fifo_size;
}

static void snd_pcm_hw_convert_to_old_params(struct snd_pcm_hw_params_old *oparams,
                         struct snd_pcm_hw_params *params)
{
    unsigned int i;

    memset(oparams, 0, sizeof(*oparams));
    oparams->flags = params->flags;
    for (i = 0; i < ARRAY_SIZE(oparams->masks); i++)
        oparams->masks[i] = params->masks[i].bits[0];
    memcpy(oparams->intervals, params->intervals, sizeof(oparams->intervals));
    oparams->rmask = __NEW_TO_OLD_MASK(params->rmask);
    oparams->cmask = __NEW_TO_OLD_MASK(params->cmask);
    oparams->info = params->info;
    oparams->msbits = params->msbits;
    oparams->rate_num = params->rate_num;
    oparams->rate_den = params->rate_den;
    oparams->fifo_size = params->fifo_size;
}

static int snd_pcm_hw_refine_old_user(struct snd_pcm_substream *substream,
                      struct snd_pcm_hw_params_old __user * _oparams)
{
    struct snd_pcm_hw_params *params;
    struct snd_pcm_hw_params_old *oparams = NULL;
    int err;

    params = kmalloc(sizeof(*params), GFP_KERNEL);
    if (!params)
        return -ENOMEM;

    oparams = memdup_user(_oparams, sizeof(*oparams));
    if (IS_ERR(oparams)) {
        err = PTR_ERR(oparams);
        goto out;
    }
    snd_pcm_hw_convert_from_old_params(params, oparams);
    err = snd_pcm_hw_refine(substream, params);
    snd_pcm_hw_convert_to_old_params(oparams, params);
    if (copy_to_user(_oparams, oparams, sizeof(*oparams))) {
        if (!err)
            err = -EFAULT;
    }

    kfree(oparams);
out:
    kfree(params);
    return err;
}

static int snd_pcm_hw_params_old_user(struct snd_pcm_substream *substream,
                      struct snd_pcm_hw_params_old __user * _oparams)
{
    struct snd_pcm_hw_params *params;
    struct snd_pcm_hw_params_old *oparams = NULL;
    int err;

    params = kmalloc(sizeof(*params), GFP_KERNEL);
    if (!params)
        return -ENOMEM;

    oparams = memdup_user(_oparams, sizeof(*oparams));
    if (IS_ERR(oparams)) {
        err = PTR_ERR(oparams);
        goto out;
    }
    snd_pcm_hw_convert_from_old_params(params, oparams);
    err = snd_pcm_hw_params(substream, params);
    snd_pcm_hw_convert_to_old_params(oparams, params);
    if (copy_to_user(_oparams, oparams, sizeof(*oparams))) {
        if (!err)
            err = -EFAULT;
    }

    kfree(oparams);
out:
    kfree(params);
    return err;
}
#endif /* CONFIG_SND_SUPPORT_OLD_API */

#ifndef CONFIG_MMU
static unsigned long snd_pcm_get_unmapped_area(struct file *file,
                           unsigned long addr,
                           unsigned long len,
                           unsigned long pgoff,
                           unsigned long flags)
{
    struct snd_pcm_file *pcm_file = file->private_data;
    struct snd_pcm_substream *substream = pcm_file->substream;
    struct snd_pcm_runtime *runtime = substream->runtime;
    unsigned long offset = pgoff << PAGE_SHIFT;

    switch (offset) {
    case SNDRV_PCM_MMAP_OFFSET_STATUS:
        return (unsigned long)runtime->status;
    case SNDRV_PCM_MMAP_OFFSET_CONTROL:
        return (unsigned long)runtime->control;
    default:
        return (unsigned long)runtime->dma_area + offset;
    }
}
#else
# define snd_pcm_get_unmapped_area NULL
#endif

/*
 *  Register section
 */

const struct file_operations snd_pcm_f_ops[2] = {
    {
        .owner =        THIS_MODULE,
        .write =        snd_pcm_write,
        .aio_write =        snd_pcm_aio_write,
        .open =         snd_pcm_playback_open,
        .release =      snd_pcm_release,
        .llseek =       no_llseek,
        .poll =         snd_pcm_playback_poll,
        .unlocked_ioctl =   snd_pcm_playback_ioctl,
        .compat_ioctl =     snd_pcm_ioctl_compat,
        .mmap =         snd_pcm_mmap,
        .fasync =       snd_pcm_fasync,
        .get_unmapped_area =    snd_pcm_get_unmapped_area,
    },
    {
        .owner =        THIS_MODULE,
        .read =         snd_pcm_read,
        .aio_read =     snd_pcm_aio_read,
        .open =         snd_pcm_capture_open,
        .release =      snd_pcm_release,
        .llseek =       no_llseek,
        .poll =         snd_pcm_capture_poll,
        .unlocked_ioctl =   snd_pcm_capture_ioctl,
        .compat_ioctl =     snd_pcm_ioctl_compat,
        .mmap =         snd_pcm_mmap,
        .fasync =       snd_pcm_fasync,
        .get_unmapped_area =    snd_pcm_get_unmapped_area,
    }
};