sound/core/pcm_native.c - kernel/msm-4.19 - Gitiles

 /*
  *  Digital Audio (PCM) abstract layer
  *  Copyright (c) by Jaroslav Kysela <perex@suse.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 <sound/driver.h>
 #include <linux/mm.h>
 #include <linux/smp_lock.h>
 #include <linux/file.h>
 #include <linux/slab.h>
 #include <linux/time.h>
 #include <linux/uio.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>

 /*
  *  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);
 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;

 	snd_assert(substream != NULL, return -ENXIO);
 	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
 char *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("%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("%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("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;
 	if (!params->fifo_size)
 		params->fifo_size = hw->fifo_size;
 	params->rmask = 0;
 	return 0;
 }

 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 = kmalloc(sizeof(*params), GFP_KERNEL);
 	if (!params) {
 		err = -ENOMEM;
 		goto out;
 	}
 	if (copy_from_user(params, _params, sizeof(*params))) {
 		err = -EFAULT;
 		goto out;
 	}
 	err = snd_pcm_hw_refine(substream, params);
 	if (copy_to_user(_params, params, sizeof(*params))) {
 		if (!err)
 			err = -EFAULT;
 	}
 out:
 	kfree(params);
 	return err;
 }

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

 	snd_assert(substream != NULL, return -ENXIO);
 	runtime = substream->runtime;
 	snd_assert(runtime != NULL, return -ENXIO);
 	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(&runtime->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->tick_time = params_tick_time(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->sleep_min = 0;
 	runtime->control->avail_min = runtime->period_size;
 	runtime->xfer_align = 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;
 	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 = kmalloc(sizeof(*params), GFP_KERNEL);
 	if (!params) {
 		err = -ENOMEM;
 		goto out;
 	}
 	if (copy_from_user(params, _params, sizeof(*params))) {
 		err = -EFAULT;
 		goto out;
 	}
 	err = snd_pcm_hw_params(substream, params);
 	if (copy_to_user(_params, params, sizeof(*params))) {
 		if (!err)
 			err = -EFAULT;
 	}
 out:
 	kfree(params);
 	return err;
 }

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

 	snd_assert(substream != NULL, return -ENXIO);
 	runtime = substream->runtime;
 	snd_assert(runtime != NULL, return -ENXIO);
 	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(&runtime->mmap_count))
 		return -EBADFD;
 	if (substream->ops->hw_free)
 		result = substream->ops->hw_free(substream);
 	runtime->status->state = SNDRV_PCM_STATE_OPEN;
 	return result;
 }

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

 	snd_assert(substream != NULL, return -ENXIO);
 	runtime = substream->runtime;
 	snd_assert(runtime != NULL, return -ENXIO);
 	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->xfer_align == 0 ||
 	    params->xfer_align % runtime->min_align != 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;
 	}
 	snd_pcm_stream_lock_irq(substream);
 	runtime->tstamp_mode = params->tstamp_mode;
 	runtime->sleep_min = params->sleep_min;
 	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;
 	runtime->xfer_align = params->xfer_align;
         params->boundary = runtime->boundary;
 	if (snd_pcm_running(substream)) {
 		if (runtime->sleep_min)
 			snd_pcm_tick_prepare(substream);
 		else
 			snd_pcm_tick_set(substream, 0);
 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 		    runtime->silence_size > 0)
 			snd_pcm_playback_silence(substream, ULONG_MAX);
 		wake_up(&runtime->sleep);
 	}
 	snd_pcm_stream_unlock_irq(substream);
 	return 0;
 }

 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_MMAP)
 			status->tstamp = runtime->status->tstamp;
 		else
 			getnstimeofday(&status->tstamp);
 	} else
 		getnstimeofday(&status->tstamp);
 	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;
 		else
 			status->delay = 0;
 	} else {
 		status->avail = snd_pcm_capture_avail(runtime);
 		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
 			status->delay = status->avail;
 		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;
 	struct snd_pcm_runtime *runtime;
 	int res;

 	snd_assert(substream != NULL, return -ENXIO);
 	runtime = substream->runtime;
 	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;

 	snd_assert(substream != NULL, return -ENXIO);
 	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) {
 		getnstimeofday(&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 list_head *pos;
 	struct snd_pcm_substream *s = NULL;
 	struct snd_pcm_substream *s1;
 	int res = 0;

 	snd_pcm_group_for_each(pos, substream) {
 		s = snd_pcm_group_substream_entry(pos);
 		if (do_lock && s != substream)
 			spin_lock(&s->self_group.lock);
 		res = ops->pre_action(s, state);
 		if (res < 0)
 			goto _unlock;
 	}
 	snd_pcm_group_for_each(pos, substream) {
 		s = snd_pcm_group_substream_entry(pos);
 		res = ops->do_action(s, state);
 		if (res < 0) {
 			if (ops->undo_action) {
 				snd_pcm_group_for_each(pos, substream) {
 					s1 = snd_pcm_group_substream_entry(pos);
 					if (s1 == s) /* failed stream */
 						break;
 					ops->undo_action(s1, state);
 				}
 			}
 			s = NULL; /* unlock all */
 			goto _unlock;
 		}
 	}
 	snd_pcm_group_for_each(pos, substream) {
 		s = snd_pcm_group_substream_entry(pos);
 		ops->post_action(s, state);
 	}
  _unlock:
 	if (do_lock) {
 		/* unlock streams */
 		snd_pcm_group_for_each(pos, substream) {
 			s1 = snd_pcm_group_substream_entry(pos);
 			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->status->state = state;
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 	    runtime->silence_size > 0)
 		snd_pcm_playback_silence(substream, ULONG_MAX);
 	if (runtime->sleep_min)
 		snd_pcm_tick_prepare(substream);
 	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
  * @substream: the PCM substream instance
  *
  * Start all linked streams.
  */
 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;
 		snd_pcm_tick_set(substream, 0);
 	}
 	wake_up(&runtime->sleep);
 }

 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
  * @substream: the PCM substream instance
  * @state: PCM state after stopping the stream
  *
  * Try to stop all running streams in the substream group.
  * The state of each stream is changed to the given value after that unconditionally.
  */
 int snd_pcm_stop(struct snd_pcm_substream *substream, int state)
 {
 	return snd_pcm_action(&snd_pcm_action_stop, substream, state);
 }

 /**
  * snd_pcm_drain_done
  * @substream: the PCM substream
  *
  * Stop the DMA only when the given stream is playback.
  * 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;
 	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);
 		snd_pcm_tick_set(substream, 0);
 		wake_up(&runtime->sleep);
 	} else {
 		runtime->status->state = SNDRV_PCM_STATE_RUNNING;
 		if (runtime->sleep_min)
 			snd_pcm_tick_prepare(substream);
 		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;
 	snd_pcm_tick_set(substream, 0);
 	wake_up(&runtime->sleep);
 }

 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
  * @substream: the PCM substream
  *
  * Trigger SUSPEND to all linked streams.
  * 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;
 }

 /**
  * snd_pcm_suspend_all
  * @pcm: the PCM instance
  *
  * Trigger SUSPEND to all substreams in the given pcm.
  * 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;
 }

 /* 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;
 	if (runtime->sleep_min)
 		snd_pcm_tick_prepare(substream);
 }

 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, substream->ffile)) >= 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, substream->ffile);
 		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;
 	// snd_assert(runtime->status->hw_ptr < runtime->buffer_size, );
 	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
  */
 static int snd_pcm_pre_prepare(struct snd_pcm_substream *substream, int state)
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
 		return -EBADFD;
 	if (snd_pcm_running(substream))
 		return -EBUSY;
 	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
  * @substream: the PCM substream instance
  *
  * Prepare the PCM substream to be triggerable.
  */
 int snd_pcm_prepare(struct snd_pcm_substream *substream)
 {
 	int res;
 	struct snd_card *card = substream->pcm->card;

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

 /*
  * drain ioctl
  */

 static int snd_pcm_pre_drain_init(struct snd_pcm_substream *substream, int state)
 {
 	if (substream->ffile->f_flags & O_NONBLOCK)
 		return -EAGAIN;
 	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 state = snd_pcm_capture_avail(runtime) > 0 ?
 				SNDRV_PCM_STATE_DRAINING : SNDRV_PCM_STATE_SETUP;
 			snd_pcm_do_stop(substream, state);
 			snd_pcm_post_stop(substream, 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
 };

 struct drain_rec {
 	struct snd_pcm_substream *substream;
 	wait_queue_t wait;
 	snd_pcm_uframes_t stop_threshold;
 };

 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 snd_card *card;
 	struct snd_pcm_runtime *runtime;
 	struct list_head *pos;
 	int result = 0;
 	int i, num_drecs;
 	struct drain_rec *drec, drec_tmp, *d;

 	snd_assert(substream != NULL, return -ENXIO);
 	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, substream->ffile);
 		if (result < 0) {
 			snd_power_unlock(card);
 			return result;
 		}
 	}

 	/* allocate temporary record for drain sync */
 	down_read(&snd_pcm_link_rwsem);
 	if (snd_pcm_stream_linked(substream)) {
 		drec = kmalloc(substream->group->count * sizeof(*drec), GFP_KERNEL);
 		if (! drec) {
 			up_read(&snd_pcm_link_rwsem);
 			snd_power_unlock(card);
 			return -ENOMEM;
 		}
 	} else
 		drec = &drec_tmp;

 	/* count only playback streams */
 	num_drecs = 0;
 	snd_pcm_group_for_each(pos, substream) {
 		struct snd_pcm_substream *s = snd_pcm_group_substream_entry(pos);
 		runtime = s->runtime;
 		if (s->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 			d = &drec[num_drecs++];
 			d->substream = s;
 			init_waitqueue_entry(&d->wait, current);
 			add_wait_queue(&runtime->sleep, &d->wait);
 			/* stop_threshold fixup to avoid endless loop when
 			 * stop_threshold > buffer_size
 			 */
 			d->stop_threshold = runtime->stop_threshold;
 			if (runtime->stop_threshold > runtime->buffer_size)
 				runtime->stop_threshold = runtime->buffer_size;
 		}
 	}
 	up_read(&snd_pcm_link_rwsem);
 	if (! num_drecs)
 		goto _error;

 	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) {
 		snd_pcm_stream_unlock_irq(substream);
 		goto _error;
 	}

 	for (;;) {
 		long tout;
 		if (signal_pending(current)) {
 			result = -ERESTARTSYS;
 			break;
 		}
 		/* all finished? */
 		for (i = 0; i < num_drecs; i++) {
 			runtime = drec[i].substream->runtime;
 			if (runtime->status->state == SNDRV_PCM_STATE_DRAINING)
 				break;
 		}
 		if (i == num_drecs)
 			break; /* yes, all drained */

 		set_current_state(TASK_INTERRUPTIBLE);
 		snd_pcm_stream_unlock_irq(substream);
 		snd_power_unlock(card);
 		tout = schedule_timeout(10 * HZ);
 		snd_power_lock(card);
 		snd_pcm_stream_lock_irq(substream);
 		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;
 		}
 	}

 	snd_pcm_stream_unlock_irq(substream);

  _error:
 	for (i = 0; i < num_drecs; i++) {
 		d = &drec[i];
 		runtime = d->substream->runtime;
 		remove_wait_queue(&runtime->sleep, &d->wait);
 		runtime->stop_threshold = d->stop_threshold;
 	}

 	if (drec != &drec_tmp)
 		kfree(drec);
 	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;

 	snd_assert(substream != NULL, return -ENXIO);
 	runtime = substream->runtime;
 	card = substream->pcm->card;

 	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, substream->ffile);
 		if (result < 0)
 			goto _unlock;
 	}

 	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);
  _unlock:
 	snd_power_unlock(card);
 	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_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 list_head *pos;
 	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(pos, substream) {
 			relink_to_local(snd_pcm_group_substream_entry(pos));
 			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 };

 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),
 				 ARRAY_SIZE(rates), rates, 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);
 	snd_assert(err >= 0, return -EINVAL);

 	err = snd_pcm_hw_constraint_mask64(runtime, SNDRV_PCM_HW_PARAM_FORMAT, hw->formats);
 	snd_assert(err >= 0, return -EINVAL);

 	err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_SUBFORMAT, 1 << SNDRV_PCM_SUBFORMAT_STD);
 	snd_assert(err >= 0, return -EINVAL);

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

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

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

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

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

 	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);
 		snd_assert(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_minmax(runtime, SNDRV_PCM_HW_PARAM_TICK_TIME,
 				     1000000 / HZ, 1000000 / HZ);
 	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIOD_SIZE);

 	return 0;
 }

 static void snd_pcm_add_file(struct snd_pcm_str *str,
 			     struct snd_pcm_file *pcm_file)
 {
 	pcm_file->next = str->files;
 	str->files = pcm_file;
 }

 static void snd_pcm_remove_file(struct snd_pcm_str *str,
 				struct snd_pcm_file *pcm_file)
 {
 	struct snd_pcm_file * pcm_file1;
 	if (str->files == pcm_file) {
 		str->files = pcm_file->next;
 	} else {
 		pcm_file1 = str->files;
 		while (pcm_file1 && pcm_file1->next != pcm_file)
 			pcm_file1 = pcm_file1->next;
 		if (pcm_file1 != NULL)
 			pcm_file1->next = pcm_file->next;
 	}
 }

 static int snd_pcm_release_file(struct snd_pcm_file * pcm_file)
 {
 	struct snd_pcm_substream *substream;
 	struct snd_pcm_runtime *runtime;
 	struct snd_pcm_str * str;

 	snd_assert(pcm_file != NULL, return -ENXIO);
 	substream = pcm_file->substream;
 	snd_assert(substream != NULL, return -ENXIO);
 	runtime = substream->runtime;
 	str = substream->pstr;
 	snd_pcm_unlink(substream);
 	if (substream->ffile != NULL) {
 		if (substream->ops->hw_free != NULL)
 			substream->ops->hw_free(substream);
 		substream->ops->close(substream);
 		substream->ffile = NULL;
 	}
 	snd_pcm_remove_file(str, pcm_file);
 	snd_pcm_release_substream(substream);
 	kfree(pcm_file);
 	return 0;
 }

 static int snd_pcm_open_file(struct file *file,
 			     struct snd_pcm *pcm,
 			     int stream,
 			     struct snd_pcm_file **rpcm_file)
 {
 	int err = 0;
 	struct snd_pcm_file *pcm_file;
 	struct snd_pcm_substream *substream;
 	struct snd_pcm_str *str;

 	snd_assert(rpcm_file != NULL, return -EINVAL);
 	*rpcm_file = NULL;

 	pcm_file = kzalloc(sizeof(*pcm_file), GFP_KERNEL);
 	if (pcm_file == NULL) {
 		return -ENOMEM;
 	}

 	if ((err = snd_pcm_open_substream(pcm, stream, &substream)) < 0) {
 		kfree(pcm_file);
 		return err;
 	}

 	str = substream->pstr;
 	substream->file = pcm_file;
 	substream->no_mmap_ctrl = 0;

 	pcm_file->substream = substream;

 	snd_pcm_add_file(str, pcm_file);

 	err = snd_pcm_hw_constraints_init(substream);
 	if (err < 0) {
 		snd_printd("snd_pcm_hw_constraints_init failed\n");
 		snd_pcm_release_file(pcm_file);
 		return err;
 	}

 	if ((err = substream->ops->open(substream)) < 0) {
 		snd_pcm_release_file(pcm_file);
 		return err;
 	}
 	substream->ffile = file;

 	err = snd_pcm_hw_constraints_complete(substream);
 	if (err < 0) {
 		snd_printd("snd_pcm_hw_constraints_complete failed\n");
 		snd_pcm_release_file(pcm_file);
 		return err;
 	}

 	file->private_data = pcm_file;
 	*rpcm_file = pcm_file;
 	return 0;
 }

 static int snd_pcm_playback_open(struct inode *inode, struct file *file)
 {
 	struct snd_pcm *pcm;

 	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;

 	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;
 	snd_assert(substream != NULL, return -ENXIO);
 	snd_assert(!atomic_read(&substream->runtime->mmap_count), );
 	pcm = substream->pcm;
 	snd_pcm_drop(substream);
 	fasync_helper(-1, file, 0, &substream->runtime->fasync);
 	mutex_lock(&pcm->open_mutex);
 	snd_pcm_release_file(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;
 	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;
 	else
 		frames -= frames % runtime->xfer_align;
 	appl_ptr = runtime->control->appl_ptr - frames;
 	if (appl_ptr < 0)
 		appl_ptr += runtime->boundary;
 	runtime->control->appl_ptr = appl_ptr;
 	if (runtime->status->state == SNDRV_PCM_STATE_RUNNING &&
 	    runtime->sleep_min)
 		snd_pcm_tick_prepare(substream);
 	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;
 	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;
 	else
 		frames -= frames % runtime->xfer_align;
 	appl_ptr = runtime->control->appl_ptr - frames;
 	if (appl_ptr < 0)
 		appl_ptr += runtime->boundary;
 	runtime->control->appl_ptr = appl_ptr;
 	if (runtime->status->state == SNDRV_PCM_STATE_RUNNING &&
 	    runtime->sleep_min)
 		snd_pcm_tick_prepare(substream);
 	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;
 	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;
 	else
 		frames -= frames % runtime->xfer_align;
 	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;
 	if (runtime->status->state == SNDRV_PCM_STATE_RUNNING &&
 	    runtime->sleep_min)
 		snd_pcm_tick_prepare(substream);
 	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;
 	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;
 	else
 		frames -= frames % runtime->xfer_align;
 	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;
 	if (runtime->status->state == SNDRV_PCM_STATE_RUNNING &&
 	    runtime->sleep_min)
 		snd_pcm_tick_prepare(substream);
 	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);
 		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_playback_ioctl1(struct snd_pcm_substream *substream,
 				   unsigned int cmd, void __user *arg);
 static int snd_pcm_capture_ioctl1(struct snd_pcm_substream *substream,
 				  unsigned int cmd, void __user *arg);

 static int snd_pcm_common_ioctl1(struct snd_pcm_substream *substream,
 				 unsigned int cmd, void __user *arg)
 {
 	snd_assert(substream != NULL, return -ENXIO);

 	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_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);
 	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);
 	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 snd_pcm_substream *substream,
 				   unsigned int cmd, void __user *arg)
 {
 	snd_assert(substream != NULL, return -ENXIO);
 	snd_assert(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 = kmalloc(sizeof(void *) * runtime->channels, GFP_KERNEL);
 		if (bufs == NULL)
 			return -ENOMEM;
 		if (copy_from_user(bufs, xfern.bufs, sizeof(void *) * runtime->channels)) {
 			kfree(bufs);
 			return -EFAULT;
 		}
 		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(substream, cmd, arg);
 }

 static int snd_pcm_capture_ioctl1(struct snd_pcm_substream *substream,
 				  unsigned int cmd, void __user *arg)
 {
 	snd_assert(substream != NULL, return -ENXIO);
 	snd_assert(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 = kmalloc(sizeof(void *) * runtime->channels, GFP_KERNEL);
 		if (bufs == NULL)
 			return -ENOMEM;
 		if (copy_from_user(bufs, xfern.bufs, sizeof(void *) * runtime->channels)) {
 			kfree(bufs);
 			return -EFAULT;
 		}
 		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(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(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(pcm_file->substream, cmd, (void __user *)arg);
 }

 int snd_pcm_kernel_playback_ioctl(struct snd_pcm_substream *substream,
 				  unsigned int cmd, void *arg)
 {
 	mm_segment_t fs;
 	int result;

 	fs = snd_enter_user();
 	result = snd_pcm_playback_ioctl1(substream, cmd, (void __user *)arg);
 	snd_leave_user(fs);
 	return result;
 }

 int snd_pcm_kernel_capture_ioctl(struct snd_pcm_substream *substream,
 				 unsigned int cmd, void *arg)
 {
 	mm_segment_t fs;
 	int result;

 	fs = snd_enter_user();
 	result = snd_pcm_capture_ioctl1(substream, cmd, (void __user *)arg);
 	snd_leave_user(fs);
 	return result;
 }

 int snd_pcm_kernel_ioctl(struct snd_pcm_substream *substream,
 			 unsigned int cmd, void *arg)
 {
 	switch (substream->stream) {
 	case SNDRV_PCM_STREAM_PLAYBACK:
 		return snd_pcm_kernel_playback_ioctl(substream, cmd, arg);
 	case SNDRV_PCM_STREAM_CAPTURE:
 		return snd_pcm_kernel_capture_ioctl(substream, cmd, arg);
 	default:
 		return -EINVAL;
 	}
 }

 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;
 	snd_assert(substream != NULL, 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;
 	snd_assert(substream != NULL, result = -ENXIO; goto end);
 	runtime = substream->runtime;
 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 		result = -EBADFD;
 		goto end;
 	}
 	if (!frame_aligned(runtime, count)) {
 		result = -EINVAL;
 		goto end;
 	}
 	count = bytes_to_frames(runtime, count);
 	result = snd_pcm_lib_write(substream, buf, count);
 	if (result > 0)
 		result = frames_to_bytes(runtime, result);
  end:
 	return result;
 }

 static ssize_t snd_pcm_readv(struct file *file, const struct iovec *_vector,
 			     unsigned long 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;
 	unsigned long i;
 	void __user **bufs;
 	snd_pcm_uframes_t frames;

 	pcm_file = file->private_data;
 	substream = pcm_file->substream;
 	snd_assert(substream != NULL, return -ENXIO);
 	runtime = substream->runtime;
 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
 		return -EBADFD;
 	if (count > 1024 || count != runtime->channels)
 		return -EINVAL;
 	if (!frame_aligned(runtime, _vector->iov_len))
 		return -EINVAL;
 	frames = bytes_to_samples(runtime, _vector->iov_len);
 	bufs = kmalloc(sizeof(void *) * count, GFP_KERNEL);
 	if (bufs == NULL)
 		return -ENOMEM;
 	for (i = 0; i < count; ++i)
 		bufs[i] = _vector[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_writev(struct file *file, const struct iovec *_vector,
 			      unsigned long 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;
 	unsigned long i;
 	void __user **bufs;
 	snd_pcm_uframes_t frames;

 	pcm_file = file->private_data;
 	substream = pcm_file->substream;
 	snd_assert(substream != NULL, result = -ENXIO; goto end);
 	runtime = substream->runtime;
 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 		result = -EBADFD;
 		goto end;
 	}
 	if (count > 128 || count != runtime->channels ||
 	    !frame_aligned(runtime, _vector->iov_len)) {
 		result = -EINVAL;
 		goto end;
 	}
 	frames = bytes_to_samples(runtime, _vector->iov_len);
 	bufs = kmalloc(sizeof(void *) * count, GFP_KERNEL);
 	if (bufs == NULL)
 		return -ENOMEM;
 	for (i = 0; i < count; ++i)
 		bufs[i] = _vector[i].iov_base;
 	result = snd_pcm_lib_writev(substream, bufs, frames);
 	if (result > 0)
 		result = frames_to_bytes(runtime, result);
 	kfree(bufs);
  end:
 	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;
 	snd_assert(substream != NULL, 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;
 	snd_assert(substream != NULL, 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 struct page * snd_pcm_mmap_status_nopage(struct vm_area_struct *area,
 						unsigned long address, int *type)
 {
 	struct snd_pcm_substream *substream = area->vm_private_data;
 	struct snd_pcm_runtime *runtime;
 	struct page * page;

 	if (substream == NULL)
 		return NOPAGE_OOM;
 	runtime = substream->runtime;
 	page = virt_to_page(runtime->status);
 	get_page(page);
 	if (type)
 		*type = VM_FAULT_MINOR;
 	return page;
 }

 static struct vm_operations_struct snd_pcm_vm_ops_status =
 {
 	.nopage =	snd_pcm_mmap_status_nopage,
 };

 static int snd_pcm_mmap_status(struct snd_pcm_substream *substream, struct file *file,
 			       struct vm_area_struct *area)
 {
 	struct snd_pcm_runtime *runtime;
 	long size;
 	if (!(area->vm_flags & VM_READ))
 		return -EINVAL;
 	runtime = substream->runtime;
 	snd_assert(runtime != NULL, return -EAGAIN);
 	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_RESERVED;
 	return 0;
 }

 /*
  * mmap control record
  */
 static struct page * snd_pcm_mmap_control_nopage(struct vm_area_struct *area,
 						 unsigned long address, int *type)
 {
 	struct snd_pcm_substream *substream = area->vm_private_data;
 	struct snd_pcm_runtime *runtime;
 	struct page * page;

 	if (substream == NULL)
 		return NOPAGE_OOM;
 	runtime = substream->runtime;
 	page = virt_to_page(runtime->control);
 	get_page(page);
 	if (type)
 		*type = VM_FAULT_MINOR;
 	return page;
 }

 static struct vm_operations_struct snd_pcm_vm_ops_control =
 {
 	.nopage =	snd_pcm_mmap_control_nopage,
 };

 static int snd_pcm_mmap_control(struct snd_pcm_substream *substream, struct file *file,
 				struct vm_area_struct *area)
 {
 	struct snd_pcm_runtime *runtime;
 	long size;
 	if (!(area->vm_flags & VM_READ))
 		return -EINVAL;
 	runtime = substream->runtime;
 	snd_assert(runtime != NULL, return -EAGAIN);
 	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_RESERVED;
 	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 */

 /*
  * nopage callback for mmapping a RAM page
  */
 static struct page *snd_pcm_mmap_data_nopage(struct vm_area_struct *area,
 					     unsigned long address, int *type)
 {
 	struct snd_pcm_substream *substream = area->vm_private_data;
 	struct snd_pcm_runtime *runtime;
 	unsigned long offset;
 	struct page * page;
 	void *vaddr;
 	size_t dma_bytes;

 	if (substream == NULL)
 		return NOPAGE_OOM;
 	runtime = substream->runtime;
 	offset = area->vm_pgoff << PAGE_SHIFT;
 	offset += address - area->vm_start;
 	snd_assert((offset % PAGE_SIZE) == 0, return NOPAGE_OOM);
 	dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
 	if (offset > dma_bytes - PAGE_SIZE)
 		return NOPAGE_SIGBUS;
 	if (substream->ops->page) {
 		page = substream->ops->page(substream, offset);
 		if (! page)
 			return NOPAGE_OOM;
 	} else {
 		vaddr = runtime->dma_area + offset;
 		page = virt_to_page(vaddr);
 	}
 	get_page(page);
 	if (type)
 		*type = VM_FAULT_MINOR;
 	return page;
 }

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

 /*
  * mmap the DMA buffer on RAM
  */
 static int snd_pcm_default_mmap(struct snd_pcm_substream *substream,
 				struct vm_area_struct *area)
 {
 	area->vm_ops = &snd_pcm_vm_ops_data;
 	area->vm_private_data = substream;
 	area->vm_flags |= VM_RESERVED;
 	atomic_inc(&substream->runtime->mmap_count);
 	return 0;
 }

 /*
  * mmap the DMA buffer on I/O memory area
  */
 #if SNDRV_PCM_INFO_MMAP_IOMEM
 static struct vm_operations_struct snd_pcm_vm_ops_data_mmio =
 {
 	.open =		snd_pcm_mmap_data_open,
 	.close =	snd_pcm_mmap_data_close,
 };

 int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream,
 			   struct vm_area_struct *area)
 {
 	long size;
 	unsigned long offset;

 #ifdef pgprot_noncached
 	area->vm_page_prot = pgprot_noncached(area->vm_page_prot);
 #endif
 	area->vm_ops = &snd_pcm_vm_ops_data_mmio;
 	area->vm_private_data = substream;
 	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;
 	atomic_inc(&substream->runtime->mmap_count);
 	return 0;
 }
 #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;

 	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;
 	snd_assert(runtime != NULL, return -EAGAIN);
 	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;

 	if (substream->ops->mmap)
 		return substream->ops->mmap(substream, area);
 	else
 		return snd_pcm_default_mmap(substream, area);
 }

 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;
 	snd_assert(substream != NULL, return -ENXIO);

 	offset = area->vm_pgoff << PAGE_SHIFT;
 	switch (offset) {
 	case SNDRV_PCM_MMAP_OFFSET_STATUS:
 		if (substream->no_mmap_ctrl)
 			return -ENXIO;
 		return snd_pcm_mmap_status(substream, file, area);
 	case SNDRV_PCM_MMAP_OFFSET_CONTROL:
 		if (substream->no_mmap_ctrl)
 			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;
 	int err;

 	pcm_file = file->private_data;
 	substream = pcm_file->substream;
 	snd_assert(substream != NULL, return -ENXIO);
 	runtime = substream->runtime;

 	err = fasync_helper(fd, file, on, &runtime->fasync);
 	if (err < 0)
 		return err;
 	return 0;
 }

 /*
  * 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) {
 		err = -ENOMEM;
 		goto out;
 	}
 	oparams = kmalloc(sizeof(*oparams), GFP_KERNEL);
 	if (!oparams) {
 		err = -ENOMEM;
 		goto out;
 	}

 	if (copy_from_user(oparams, _oparams, sizeof(*oparams))) {
 		err = -EFAULT;
 		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;
 	}
 out:
 	kfree(params);
 	kfree(oparams);
 	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) {
 		err = -ENOMEM;
 		goto out;
 	}
 	oparams = kmalloc(sizeof(*oparams), GFP_KERNEL);
 	if (!oparams) {
 		err = -ENOMEM;
 		goto out;
 	}
 	if (copy_from_user(oparams, _oparams, sizeof(*oparams))) {
 		err = -EFAULT;
 		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;
 	}
 out:
 	kfree(params);
 	kfree(oparams);
 	return err;
 }
 #endif /* CONFIG_SND_SUPPORT_OLD_API */

 /*
  *  Register section
  */

 struct file_operations snd_pcm_f_ops[2] = {
 	{
 		.owner =		THIS_MODULE,
 		.write =		snd_pcm_write,
 		.writev =		snd_pcm_writev,
 		.open =			snd_pcm_playback_open,
 		.release =		snd_pcm_release,
 		.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,
 	},
 	{
 		.owner =		THIS_MODULE,
 		.read =			snd_pcm_read,
 		.readv =		snd_pcm_readv,
 		.open =			snd_pcm_capture_open,
 		.release =		snd_pcm_release,
 		.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,
 	}
 };