/*
   *  Digital Audio (PCM) abstract layer

   *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>

   *
   *
   *   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/file.h>
  #include <linux/slab.h>

  #include <linux/smp_lock.h>

  #include <linux/time.h>

  #include <linux/pm_qos_params.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
  ", 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
  ");
  		else 
  			printk("%c%u %u%c
  ", 
  			       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("
  ");
  #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 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;
  
  	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);
  	runtime->status->state = 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 unuseable from this time,
  	   so we force application to retry to set
  	   the correct hardware parameter settings */
  	runtime->status->state = 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);
  	runtime->status->state = 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
  };
  
  /**

   * snd_pcm_start - start all linked streams

   * @substream: the PCM substream instance

   */

  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
  };
  
  /**

   * snd_pcm_stop - try to stop all running streams in the substream group

   * @substream: the PCM substream instance
   * @state: PCM state after stopping the stream

   *

   * The state of each stream is then changed to the given state unconditionally.

   */

  int snd_pcm_stop(struct snd_pcm_substream *substream, int state)

  {
  	return snd_pcm_action(&snd_pcm_action_stop, substream, state);
  }

  EXPORT_SYMBOL(snd_pcm_stop);

  /**

   * snd_pcm_drain_done - stop the DMA only when the given stream is playback

   * @substream: the PCM substream

   *

   * After stopping, the state is changed to SETUP.

   * Unlike snd_pcm_stop(), this affects only the given stream.
   */

  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 betwen 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
  };
  
  /**

   * snd_pcm_suspend - trigger SUSPEND to all linked streams

   * @substream: the PCM substream

   *

   * After this call, all streams are changed to SUSPENDED state.
   */

  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);

  /**

   * snd_pcm_suspend_all - trigger SUSPEND to all substreams in the given pcm

   * @pcm: the PCM instance

   *

   * After this call, all streams are changed to SUSPENDED state.
   */

  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;
  	runtime->status->state = 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
  };
  
  /**

   * snd_pcm_prepare - prepare the PCM substream to be triggerable

   * @substream: the PCM substream instance

   * @file: file to refer f_flags

   */

  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)

  {

  	substream->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;
  		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);

  		set_current_state(TASK_INTERRUPTIBLE);
  		snd_pcm_stream_unlock_irq(substream);

  		up_read(&snd_pcm_link_rwsem);

  		snd_power_unlock(card);
  		tout = schedule_timeout(10 * HZ);
  		snd_power_lock(card);

  		down_read(&snd_pcm_link_rwsem);

  		snd_pcm_stream_lock_irq(substream);

  		remove_wait_queue(&to_check->sleep, &wait);

  		if (tout == 0) {
  			if (substream->runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
  				result = -ESTRPIPE;
  			else {
  				snd_printd("playback drain error (DMA or IRQ trouble?)
  ");
  				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;
  	struct snd_card *card;

  	int result = 0;
  	

  	if (PCM_RUNTIME_CHECK(substream))
  		return -ENXIO;

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

  	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)
  {
  	struct file *file;
  	struct inode *inode;

  	unsigned int minor;

  	file = fget(fd);
  	if (!file)
  		return NULL;

  	inode = file->f_path.dentry->d_inode;

  	if (!S_ISCHR(inode->i_mode) ||
  	    imajor(inode) != snd_major) {
  		fput(file);
  		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(file);
  		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;

  
  	file = snd_pcm_file_fd(fd);
  	if (!file)
  		return -EBADFD;
  	pcm_file = file->private_data;
  	substream1 = pcm_file->substream;
  	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 = kmalloc(sizeof(struct snd_pcm_group), GFP_ATOMIC);

  		if (substream->group == NULL) {
  			res = -ENOMEM;
  			goto _end;
  		}
  		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);
  	fput(file);
  	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
  ");
  		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
  ");
  		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 **rpcm_file)

  {

  	struct snd_pcm_file *pcm_file;
  	struct snd_pcm_substream *substream;
  	struct snd_pcm_str *str;

  	int err;

  	if (rpcm_file)
  		*rpcm_file = NULL;

  	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) {

  		str = substream->pstr;
  		substream->file = pcm_file;
  		substream->pcm_release = pcm_release_private;

  	}

  	file->private_data = pcm_file;

  	if (rpcm_file)
  		*rpcm_file = 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);
  	return snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK);
  }
  
  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);
  	return snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE);
  }
  
  static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream)
  {
  	int err;

  	struct snd_pcm_file *pcm_file;

  	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, &pcm_file);

  		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 (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: