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32 results

kunit_kernel.py

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  • pcm_native.c 93.77 KiB
    /*
     *  Digital Audio (PCM) abstract layer
     *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
     *
     *
     *   This program is free software; you can redistribute it and/or modify
     *   it under the terms of the GNU General Public License as published by
     *   the Free Software Foundation; either version 2 of the License, or
     *   (at your option) any later version.
     *
     *   This program is distributed in the hope that it will be useful,
     *   but WITHOUT ANY WARRANTY; without even the implied warranty of
     *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     *   GNU General Public License for more details.
     *
     *   You should have received a copy of the GNU General Public License
     *   along with this program; if not, write to the Free Software
     *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
     *
     */
    
    #include <linux/mm.h>
    #include <linux/file.h>
    #include <linux/slab.h>
    #include <linux/time.h>
    #include <linux/pm_qos_params.h>
    #include <linux/uio.h>
    #include <linux/dma-mapping.h>
    #include <sound/core.h>
    #include <sound/control.h>
    #include <sound/info.h>
    #include <sound/pcm.h>
    #include <sound/pcm_params.h>
    #include <sound/timer.h>
    #include <sound/minors.h>
    #include <asm/io.h>
    #if defined(CONFIG_MIPS) && defined(CONFIG_DMA_NONCOHERENT)
    #include <dma-coherence.h>
    #endif
    
    /*
     *  Compatibility
     */
    
    struct snd_pcm_hw_params_old {
    	unsigned int flags;
    	unsigned int masks[SNDRV_PCM_HW_PARAM_SUBFORMAT -
    			   SNDRV_PCM_HW_PARAM_ACCESS + 1];
    	struct snd_interval intervals[SNDRV_PCM_HW_PARAM_TICK_TIME -
    					SNDRV_PCM_HW_PARAM_SAMPLE_BITS + 1];
    	unsigned int rmask;
    	unsigned int cmask;
    	unsigned int info;
    	unsigned int msbits;
    	unsigned int rate_num;
    	unsigned int rate_den;
    	snd_pcm_uframes_t fifo_size;
    	unsigned char reserved[64];
    };
    
    #ifdef CONFIG_SND_SUPPORT_OLD_API
    #define SNDRV_PCM_IOCTL_HW_REFINE_OLD _IOWR('A', 0x10, struct snd_pcm_hw_params_old)
    #define SNDRV_PCM_IOCTL_HW_PARAMS_OLD _IOWR('A', 0x11, struct snd_pcm_hw_params_old)
    
    static int snd_pcm_hw_refine_old_user(struct snd_pcm_substream *substream,
    				      struct snd_pcm_hw_params_old __user * _oparams);
    static int snd_pcm_hw_params_old_user(struct snd_pcm_substream *substream,
    				      struct snd_pcm_hw_params_old __user * _oparams);
    #endif
    static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream);
    
    /*
     *
     */
    
    DEFINE_RWLOCK(snd_pcm_link_rwlock);
    EXPORT_SYMBOL(snd_pcm_link_rwlock);
    
    static DECLARE_RWSEM(snd_pcm_link_rwsem);
    
    static inline mm_segment_t snd_enter_user(void)
    {
    	mm_segment_t fs = get_fs();
    	set_fs(get_ds());
    	return fs;
    }
    
    static inline void snd_leave_user(mm_segment_t fs)
    {
    	set_fs(fs);
    }
    
    
    
    int snd_pcm_info(struct snd_pcm_substream *substream, struct snd_pcm_info *info)
    {
    	struct snd_pcm_runtime *runtime;
    	struct snd_pcm *pcm = substream->pcm;
    	struct snd_pcm_str *pstr = substream->pstr;
    
    	memset(info, 0, sizeof(*info));
    	info->card = pcm->card->number;
    	info->device = pcm->device;
    	info->stream = substream->stream;
    	info->subdevice = substream->number;
    	strlcpy(info->id, pcm->id, sizeof(info->id));
    	strlcpy(info->name, pcm->name, sizeof(info->name));
    	info->dev_class = pcm->dev_class;
    	info->dev_subclass = pcm->dev_subclass;
    	info->subdevices_count = pstr->substream_count;
    	info->subdevices_avail = pstr->substream_count - pstr->substream_opened;
    	strlcpy(info->subname, substream->name, sizeof(info->subname));
    	runtime = substream->runtime;
    	/* AB: FIXME!!! This is definitely nonsense */
    	if (runtime) {
    		info->sync = runtime->sync;
    		substream->ops->ioctl(substream, SNDRV_PCM_IOCTL1_INFO, info);
    	}
    	return 0;
    }
    
    int snd_pcm_info_user(struct snd_pcm_substream *substream,
    		      struct snd_pcm_info __user * _info)
    {
    	struct snd_pcm_info *info;
    	int err;
    
    	info = kmalloc(sizeof(*info), GFP_KERNEL);
    	if (! info)
    		return -ENOMEM;
    	err = snd_pcm_info(substream, info);
    	if (err >= 0) {
    		if (copy_to_user(_info, info, sizeof(*info)))
    			err = -EFAULT;
    	}
    	kfree(info);
    	return err;
    }
    
    #undef RULES_DEBUG
    
    #ifdef RULES_DEBUG
    #define HW_PARAM(v) [SNDRV_PCM_HW_PARAM_##v] = #v
    static const char * const snd_pcm_hw_param_names[] = {
    	HW_PARAM(ACCESS),
    	HW_PARAM(FORMAT),
    	HW_PARAM(SUBFORMAT),
    	HW_PARAM(SAMPLE_BITS),
    	HW_PARAM(FRAME_BITS),
    	HW_PARAM(CHANNELS),
    	HW_PARAM(RATE),
    	HW_PARAM(PERIOD_TIME),
    	HW_PARAM(PERIOD_SIZE),
    	HW_PARAM(PERIOD_BYTES),
    	HW_PARAM(PERIODS),
    	HW_PARAM(BUFFER_TIME),
    	HW_PARAM(BUFFER_SIZE),
    	HW_PARAM(BUFFER_BYTES),
    	HW_PARAM(TICK_TIME),
    };
    #endif
    
    int snd_pcm_hw_refine(struct snd_pcm_substream *substream, 
    		      struct snd_pcm_hw_params *params)
    {
    	unsigned int k;
    	struct snd_pcm_hardware *hw;
    	struct snd_interval *i = NULL;
    	struct snd_mask *m = NULL;
    	struct snd_pcm_hw_constraints *constrs = &substream->runtime->hw_constraints;
    	unsigned int rstamps[constrs->rules_num];
    	unsigned int vstamps[SNDRV_PCM_HW_PARAM_LAST_INTERVAL + 1];
    	unsigned int stamp = 2;
    	int changed, again;
    
    	params->info = 0;
    	params->fifo_size = 0;
    	if (params->rmask & (1 << SNDRV_PCM_HW_PARAM_SAMPLE_BITS))
    		params->msbits = 0;
    	if (params->rmask & (1 << SNDRV_PCM_HW_PARAM_RATE)) {
    		params->rate_num = 0;
    		params->rate_den = 0;
    	}
    
    	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++) {
    		m = hw_param_mask(params, k);
    		if (snd_mask_empty(m))
    			return -EINVAL;
    		if (!(params->rmask & (1 << k)))
    			continue;
    #ifdef RULES_DEBUG
    		printk(KERN_DEBUG "%s = ", snd_pcm_hw_param_names[k]);
    		printk("%04x%04x%04x%04x -> ", m->bits[3], m->bits[2], m->bits[1], m->bits[0]);
    #endif
    		changed = snd_mask_refine(m, constrs_mask(constrs, k));
    #ifdef RULES_DEBUG
    		printk("%04x%04x%04x%04x\n", m->bits[3], m->bits[2], m->bits[1], m->bits[0]);
    #endif
    		if (changed)
    			params->cmask |= 1 << k;
    		if (changed < 0)
    			return changed;
    	}
    
    	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) {
    		i = hw_param_interval(params, k);
    		if (snd_interval_empty(i))
    			return -EINVAL;
    		if (!(params->rmask & (1 << k)))
    			continue;
    #ifdef RULES_DEBUG
    		printk(KERN_DEBUG "%s = ", snd_pcm_hw_param_names[k]);
    		if (i->empty)
    			printk("empty");
    		else
    			printk("%c%u %u%c", 
    			       i->openmin ? '(' : '[', i->min,
    			       i->max, i->openmax ? ')' : ']');
    		printk(" -> ");
    #endif
    		changed = snd_interval_refine(i, constrs_interval(constrs, k));
    #ifdef RULES_DEBUG
    		if (i->empty)
    			printk("empty\n");
    		else 
    			printk("%c%u %u%c\n", 
    			       i->openmin ? '(' : '[', i->min,
    			       i->max, i->openmax ? ')' : ']');
    #endif
    		if (changed)
    			params->cmask |= 1 << k;
    		if (changed < 0)
    			return changed;
    	}
    
    	for (k = 0; k < constrs->rules_num; k++)
    		rstamps[k] = 0;
    	for (k = 0; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) 
    		vstamps[k] = (params->rmask & (1 << k)) ? 1 : 0;
    	do {
    		again = 0;
    		for (k = 0; k < constrs->rules_num; k++) {
    			struct snd_pcm_hw_rule *r = &constrs->rules[k];
    			unsigned int d;
    			int doit = 0;
    			if (r->cond && !(r->cond & params->flags))
    				continue;
    			for (d = 0; r->deps[d] >= 0; d++) {
    				if (vstamps[r->deps[d]] > rstamps[k]) {
    					doit = 1;
    					break;
    				}
    			}
    			if (!doit)
    				continue;
    #ifdef RULES_DEBUG
    			printk(KERN_DEBUG "Rule %d [%p]: ", k, r->func);
    			if (r->var >= 0) {
    				printk("%s = ", snd_pcm_hw_param_names[r->var]);
    				if (hw_is_mask(r->var)) {
    					m = hw_param_mask(params, r->var);
    					printk("%x", *m->bits);
    				} else {
    					i = hw_param_interval(params, r->var);
    					if (i->empty)
    						printk("empty");
    					else
    						printk("%c%u %u%c", 
    						       i->openmin ? '(' : '[', i->min,
    						       i->max, i->openmax ? ')' : ']');
    				}
    			}
    #endif
    			changed = r->func(params, r);
    #ifdef RULES_DEBUG
    			if (r->var >= 0) {
    				printk(" -> ");
    				if (hw_is_mask(r->var))
    					printk("%x", *m->bits);
    				else {
    					if (i->empty)
    						printk("empty");
    					else
    						printk("%c%u %u%c", 
    						       i->openmin ? '(' : '[', i->min,
    						       i->max, i->openmax ? ')' : ']');
    				}
    			}
    			printk("\n");
    #endif
    			rstamps[k] = stamp;
    			if (changed && r->var >= 0) {
    				params->cmask |= (1 << r->var);
    				vstamps[r->var] = stamp;
    				again = 1;
    			}
    			if (changed < 0)
    				return changed;
    			stamp++;
    		}
    	} while (again);
    	if (!params->msbits) {
    		i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
    		if (snd_interval_single(i))
    			params->msbits = snd_interval_value(i);
    	}
    
    	if (!params->rate_den) {
    		i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
    		if (snd_interval_single(i)) {
    			params->rate_num = snd_interval_value(i);
    			params->rate_den = 1;
    		}
    	}
    
    	hw = &substream->runtime->hw;
    	if (!params->info)
    		params->info = hw->info & ~SNDRV_PCM_INFO_FIFO_IN_FRAMES;
    	if (!params->fifo_size) {
    		m = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
    		i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
    		if (snd_mask_min(m) == snd_mask_max(m) &&
                        snd_interval_min(i) == snd_interval_max(i)) {
    			changed = substream->ops->ioctl(substream,
    					SNDRV_PCM_IOCTL1_FIFO_SIZE, params);
    			if (changed < 0)
    				return changed;
    		}
    	}
    	params->rmask = 0;
    	return 0;
    }
    
    EXPORT_SYMBOL(snd_pcm_hw_refine);
    
    static int snd_pcm_hw_refine_user(struct snd_pcm_substream *substream,
    				  struct snd_pcm_hw_params __user * _params)
    {
    	struct snd_pcm_hw_params *params;
    	int err;
    
    	params = memdup_user(_params, sizeof(*params));
    	if (IS_ERR(params))
    		return PTR_ERR(params);
    
    	err = snd_pcm_hw_refine(substream, params);
    	if (copy_to_user(_params, params, sizeof(*params))) {
    		if (!err)
    			err = -EFAULT;
    	}
    
    	kfree(params);
    	return err;
    }
    
    static int period_to_usecs(struct snd_pcm_runtime *runtime)
    {
    	int usecs;
    
    	if (! runtime->rate)
    		return -1; /* invalid */
    
    	/* take 75% of period time as the deadline */
    	usecs = (750000 / runtime->rate) * runtime->period_size;
    	usecs += ((750000 % runtime->rate) * runtime->period_size) /
    		runtime->rate;
    
    	return usecs;
    }
    
    static int snd_pcm_hw_params(struct snd_pcm_substream *substream,
    			     struct snd_pcm_hw_params *params)
    {
    	struct snd_pcm_runtime *runtime;
    	int err, usecs;
    	unsigned int bits;
    	snd_pcm_uframes_t frames;
    
    	if (PCM_RUNTIME_CHECK(substream))
    		return -ENXIO;
    	runtime = substream->runtime;
    	snd_pcm_stream_lock_irq(substream);
    	switch (runtime->status->state) {
    	case SNDRV_PCM_STATE_OPEN:
    	case SNDRV_PCM_STATE_SETUP:
    	case SNDRV_PCM_STATE_PREPARED:
    		break;
    	default:
    		snd_pcm_stream_unlock_irq(substream);
    		return -EBADFD;
    	}
    	snd_pcm_stream_unlock_irq(substream);
    #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
    	if (!substream->oss.oss)
    #endif
    		if (atomic_read(&substream->mmap_count))
    			return -EBADFD;
    
    	params->rmask = ~0U;
    	err = snd_pcm_hw_refine(substream, params);
    	if (err < 0)
    		goto _error;
    
    	err = snd_pcm_hw_params_choose(substream, params);
    	if (err < 0)
    		goto _error;
    
    	if (substream->ops->hw_params != NULL) {
    		err = substream->ops->hw_params(substream, params);
    		if (err < 0)
    			goto _error;
    	}
    
    	runtime->access = params_access(params);
    	runtime->format = params_format(params);
    	runtime->subformat = params_subformat(params);
    	runtime->channels = params_channels(params);
    	runtime->rate = params_rate(params);
    	runtime->period_size = params_period_size(params);
    	runtime->periods = params_periods(params);
    	runtime->buffer_size = params_buffer_size(params);
    	runtime->info = params->info;
    	runtime->rate_num = params->rate_num;
    	runtime->rate_den = params->rate_den;
    	runtime->no_period_wakeup =
    			(params->info & SNDRV_PCM_INFO_NO_PERIOD_WAKEUP) &&
    			(params->flags & SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP);
    
    	bits = snd_pcm_format_physical_width(runtime->format);
    	runtime->sample_bits = bits;
    	bits *= runtime->channels;
    	runtime->frame_bits = bits;
    	frames = 1;
    	while (bits % 8 != 0) {
    		bits *= 2;
    		frames *= 2;
    	}
    	runtime->byte_align = bits / 8;
    	runtime->min_align = frames;
    
    	/* Default sw params */
    	runtime->tstamp_mode = SNDRV_PCM_TSTAMP_NONE;
    	runtime->period_step = 1;
    	runtime->control->avail_min = runtime->period_size;
    	runtime->start_threshold = 1;
    	runtime->stop_threshold = runtime->buffer_size;
    	runtime->silence_threshold = 0;
    	runtime->silence_size = 0;
    	runtime->boundary = runtime->buffer_size;
    	while (runtime->boundary * 2 <= LONG_MAX - runtime->buffer_size)
    		runtime->boundary *= 2;
    
    	snd_pcm_timer_resolution_change(substream);
    	runtime->status->state = SNDRV_PCM_STATE_SETUP;
    
    	if (pm_qos_request_active(&substream->latency_pm_qos_req))
    		pm_qos_remove_request(&substream->latency_pm_qos_req);
    	if ((usecs = period_to_usecs(runtime)) >= 0)
    		pm_qos_add_request(&substream->latency_pm_qos_req,
    				   PM_QOS_CPU_DMA_LATENCY, usecs);
    	return 0;
     _error:
    	/* hardware might be unusable from this time,
    	   so we force application to retry to set
    	   the correct hardware parameter settings */
    	runtime->status->state = SNDRV_PCM_STATE_OPEN;
    	if (substream->ops->hw_free != NULL)
    		substream->ops->hw_free(substream);
    	return err;
    }
    
    static int snd_pcm_hw_params_user(struct snd_pcm_substream *substream,
    				  struct snd_pcm_hw_params __user * _params)
    {
    	struct snd_pcm_hw_params *params;
    	int err;
    
    	params = memdup_user(_params, sizeof(*params));
    	if (IS_ERR(params))
    		return PTR_ERR(params);
    
    	err = snd_pcm_hw_params(substream, params);
    	if (copy_to_user(_params, params, sizeof(*params))) {
    		if (!err)
    			err = -EFAULT;
    	}
    
    	kfree(params);
    	return err;
    }
    
    static int snd_pcm_hw_free(struct snd_pcm_substream *substream)
    {
    	struct snd_pcm_runtime *runtime;
    	int result = 0;
    
    	if (PCM_RUNTIME_CHECK(substream))
    		return -ENXIO;
    	runtime = substream->runtime;
    	snd_pcm_stream_lock_irq(substream);
    	switch (runtime->status->state) {
    	case SNDRV_PCM_STATE_SETUP:
    	case SNDRV_PCM_STATE_PREPARED:
    		break;
    	default:
    		snd_pcm_stream_unlock_irq(substream);
    		return -EBADFD;
    	}
    	snd_pcm_stream_unlock_irq(substream);
    	if (atomic_read(&substream->mmap_count))
    		return -EBADFD;
    	if (substream->ops->hw_free)
    		result = substream->ops->hw_free(substream);
    	runtime->status->state = SNDRV_PCM_STATE_OPEN;
    	pm_qos_remove_request(&substream->latency_pm_qos_req);
    	return result;
    }
    
    static int snd_pcm_sw_params(struct snd_pcm_substream *substream,
    			     struct snd_pcm_sw_params *params)
    {
    	struct snd_pcm_runtime *runtime;
    	int err;
    
    	if (PCM_RUNTIME_CHECK(substream))
    		return -ENXIO;
    	runtime = substream->runtime;
    	snd_pcm_stream_lock_irq(substream);
    	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
    		snd_pcm_stream_unlock_irq(substream);
    		return -EBADFD;
    	}
    	snd_pcm_stream_unlock_irq(substream);
    
    	if (params->tstamp_mode > SNDRV_PCM_TSTAMP_LAST)
    		return -EINVAL;
    	if (params->avail_min == 0)
    		return -EINVAL;
    	if (params->silence_size >= runtime->boundary) {
    		if (params->silence_threshold != 0)
    			return -EINVAL;
    	} else {
    		if (params->silence_size > params->silence_threshold)
    			return -EINVAL;
    		if (params->silence_threshold > runtime->buffer_size)
    			return -EINVAL;
    	}
    	err = 0;
    	snd_pcm_stream_lock_irq(substream);
    	runtime->tstamp_mode = params->tstamp_mode;
    	runtime->period_step = params->period_step;
    	runtime->control->avail_min = params->avail_min;
    	runtime->start_threshold = params->start_threshold;
    	runtime->stop_threshold = params->stop_threshold;
    	runtime->silence_threshold = params->silence_threshold;
    	runtime->silence_size = params->silence_size;
            params->boundary = runtime->boundary;
    	if (snd_pcm_running(substream)) {
    		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
    		    runtime->silence_size > 0)
    			snd_pcm_playback_silence(substream, ULONG_MAX);
    		err = snd_pcm_update_state(substream, runtime);
    	}
    	snd_pcm_stream_unlock_irq(substream);
    	return err;
    }
    
    static int snd_pcm_sw_params_user(struct snd_pcm_substream *substream,
    				  struct snd_pcm_sw_params __user * _params)
    {
    	struct snd_pcm_sw_params params;
    	int err;
    	if (copy_from_user(&params, _params, sizeof(params)))
    		return -EFAULT;
    	err = snd_pcm_sw_params(substream, &params);
    	if (copy_to_user(_params, &params, sizeof(params)))
    		return -EFAULT;
    	return err;
    }
    
    int snd_pcm_status(struct snd_pcm_substream *substream,
    		   struct snd_pcm_status *status)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    
    	snd_pcm_stream_lock_irq(substream);
    	status->state = runtime->status->state;
    	status->suspended_state = runtime->status->suspended_state;
    	if (status->state == SNDRV_PCM_STATE_OPEN)
    		goto _end;
    	status->trigger_tstamp = runtime->trigger_tstamp;
    	if (snd_pcm_running(substream)) {
    		snd_pcm_update_hw_ptr(substream);
    		if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
    			status->tstamp = runtime->status->tstamp;
    			goto _tstamp_end;
    		}
    	}
    	snd_pcm_gettime(runtime, &status->tstamp);
     _tstamp_end:
    	status->appl_ptr = runtime->control->appl_ptr;
    	status->hw_ptr = runtime->status->hw_ptr;
    	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
    		status->avail = snd_pcm_playback_avail(runtime);
    		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING ||
    		    runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
    			status->delay = runtime->buffer_size - status->avail;
    			status->delay += runtime->delay;
    		} else
    			status->delay = 0;
    	} else {
    		status->avail = snd_pcm_capture_avail(runtime);
    		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
    			status->delay = status->avail + runtime->delay;
    		else
    			status->delay = 0;
    	}
    	status->avail_max = runtime->avail_max;
    	status->overrange = runtime->overrange;
    	runtime->avail_max = 0;
    	runtime->overrange = 0;
     _end:
     	snd_pcm_stream_unlock_irq(substream);
    	return 0;
    }
    
    static int snd_pcm_status_user(struct snd_pcm_substream *substream,
    			       struct snd_pcm_status __user * _status)
    {
    	struct snd_pcm_status status;
    	int res;
    	
    	memset(&status, 0, sizeof(status));
    	res = snd_pcm_status(substream, &status);
    	if (res < 0)
    		return res;
    	if (copy_to_user(_status, &status, sizeof(status)))
    		return -EFAULT;
    	return 0;
    }
    
    static int snd_pcm_channel_info(struct snd_pcm_substream *substream,
    				struct snd_pcm_channel_info * info)
    {
    	struct snd_pcm_runtime *runtime;
    	unsigned int channel;
    	
    	channel = info->channel;
    	runtime = substream->runtime;
    	snd_pcm_stream_lock_irq(substream);
    	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
    		snd_pcm_stream_unlock_irq(substream);
    		return -EBADFD;
    	}
    	snd_pcm_stream_unlock_irq(substream);
    	if (channel >= runtime->channels)
    		return -EINVAL;
    	memset(info, 0, sizeof(*info));
    	info->channel = channel;
    	return substream->ops->ioctl(substream, SNDRV_PCM_IOCTL1_CHANNEL_INFO, info);
    }
    
    static int snd_pcm_channel_info_user(struct snd_pcm_substream *substream,
    				     struct snd_pcm_channel_info __user * _info)
    {
    	struct snd_pcm_channel_info info;
    	int res;
    	
    	if (copy_from_user(&info, _info, sizeof(info)))
    		return -EFAULT;
    	res = snd_pcm_channel_info(substream, &info);
    	if (res < 0)
    		return res;
    	if (copy_to_user(_info, &info, sizeof(info)))
    		return -EFAULT;
    	return 0;
    }
    
    static void snd_pcm_trigger_tstamp(struct snd_pcm_substream *substream)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	if (runtime->trigger_master == NULL)
    		return;
    	if (runtime->trigger_master == substream) {
    		snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
    	} else {
    		snd_pcm_trigger_tstamp(runtime->trigger_master);
    		runtime->trigger_tstamp = runtime->trigger_master->runtime->trigger_tstamp;
    	}
    	runtime->trigger_master = NULL;
    }
    
    struct action_ops {
    	int (*pre_action)(struct snd_pcm_substream *substream, int state);
    	int (*do_action)(struct snd_pcm_substream *substream, int state);
    	void (*undo_action)(struct snd_pcm_substream *substream, int state);
    	void (*post_action)(struct snd_pcm_substream *substream, int state);
    };
    
    /*
     *  this functions is core for handling of linked stream
     *  Note: the stream state might be changed also on failure
     *  Note2: call with calling stream lock + link lock
     */
    static int snd_pcm_action_group(struct action_ops *ops,
    				struct snd_pcm_substream *substream,
    				int state, int do_lock)
    {
    	struct snd_pcm_substream *s = NULL;
    	struct snd_pcm_substream *s1;
    	int res = 0;
    
    	snd_pcm_group_for_each_entry(s, substream) {
    		if (do_lock && s != substream)
    			spin_lock_nested(&s->self_group.lock,
    					 SINGLE_DEPTH_NESTING);
    		res = ops->pre_action(s, state);
    		if (res < 0)
    			goto _unlock;
    	}
    	snd_pcm_group_for_each_entry(s, substream) {
    		res = ops->do_action(s, state);
    		if (res < 0) {
    			if (ops->undo_action) {
    				snd_pcm_group_for_each_entry(s1, substream) {
    					if (s1 == s) /* failed stream */
    						break;
    					ops->undo_action(s1, state);
    				}
    			}
    			s = NULL; /* unlock all */
    			goto _unlock;
    		}
    	}
    	snd_pcm_group_for_each_entry(s, substream) {
    		ops->post_action(s, state);
    	}
     _unlock:
    	if (do_lock) {
    		/* unlock streams */
    		snd_pcm_group_for_each_entry(s1, substream) {
    			if (s1 != substream)
    				spin_unlock(&s1->self_group.lock);
    			if (s1 == s)	/* end */
    				break;
    		}
    	}
    	return res;
    }
    
    /*
     *  Note: call with stream lock
     */
    static int snd_pcm_action_single(struct action_ops *ops,
    				 struct snd_pcm_substream *substream,
    				 int state)
    {
    	int res;
    	
    	res = ops->pre_action(substream, state);
    	if (res < 0)
    		return res;
    	res = ops->do_action(substream, state);
    	if (res == 0)
    		ops->post_action(substream, state);
    	else if (ops->undo_action)
    		ops->undo_action(substream, state);
    	return res;
    }
    
    /*
     *  Note: call with stream lock
     */
    static int snd_pcm_action(struct action_ops *ops,
    			  struct snd_pcm_substream *substream,
    			  int state)
    {
    	int res;
    
    	if (snd_pcm_stream_linked(substream)) {
    		if (!spin_trylock(&substream->group->lock)) {
    			spin_unlock(&substream->self_group.lock);
    			spin_lock(&substream->group->lock);
    			spin_lock(&substream->self_group.lock);
    		}
    		res = snd_pcm_action_group(ops, substream, state, 1);
    		spin_unlock(&substream->group->lock);
    	} else {
    		res = snd_pcm_action_single(ops, substream, state);
    	}
    	return res;
    }
    
    /*
     *  Note: don't use any locks before
     */
    static int snd_pcm_action_lock_irq(struct action_ops *ops,
    				   struct snd_pcm_substream *substream,
    				   int state)
    {
    	int res;
    
    	read_lock_irq(&snd_pcm_link_rwlock);
    	if (snd_pcm_stream_linked(substream)) {
    		spin_lock(&substream->group->lock);
    		spin_lock(&substream->self_group.lock);
    		res = snd_pcm_action_group(ops, substream, state, 1);
    		spin_unlock(&substream->self_group.lock);
    		spin_unlock(&substream->group->lock);
    	} else {
    		spin_lock(&substream->self_group.lock);
    		res = snd_pcm_action_single(ops, substream, state);
    		spin_unlock(&substream->self_group.lock);
    	}
    	read_unlock_irq(&snd_pcm_link_rwlock);
    	return res;
    }
    
    /*
     */
    static int snd_pcm_action_nonatomic(struct action_ops *ops,
    				    struct snd_pcm_substream *substream,
    				    int state)
    {
    	int res;
    
    	down_read(&snd_pcm_link_rwsem);
    	if (snd_pcm_stream_linked(substream))
    		res = snd_pcm_action_group(ops, substream, state, 0);
    	else
    		res = snd_pcm_action_single(ops, substream, state);
    	up_read(&snd_pcm_link_rwsem);
    	return res;
    }
    
    /*
     * start callbacks
     */
    static int snd_pcm_pre_start(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	if (runtime->status->state != SNDRV_PCM_STATE_PREPARED)
    		return -EBADFD;
    	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
    	    !snd_pcm_playback_data(substream))
    		return -EPIPE;
    	runtime->trigger_master = substream;
    	return 0;
    }
    
    static int snd_pcm_do_start(struct snd_pcm_substream *substream, int state)
    {
    	if (substream->runtime->trigger_master != substream)
    		return 0;
    	return substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_START);
    }
    
    static void snd_pcm_undo_start(struct snd_pcm_substream *substream, int state)
    {
    	if (substream->runtime->trigger_master == substream)
    		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
    }
    
    static void snd_pcm_post_start(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	snd_pcm_trigger_tstamp(substream);
    	runtime->hw_ptr_jiffies = jiffies;
    	runtime->hw_ptr_buffer_jiffies = (runtime->buffer_size * HZ) / 
    							    runtime->rate;
    	runtime->status->state = state;
    	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
    	    runtime->silence_size > 0)
    		snd_pcm_playback_silence(substream, ULONG_MAX);
    	if (substream->timer)
    		snd_timer_notify(substream->timer, SNDRV_TIMER_EVENT_MSTART,
    				 &runtime->trigger_tstamp);
    }
    
    static struct action_ops snd_pcm_action_start = {
    	.pre_action = snd_pcm_pre_start,
    	.do_action = snd_pcm_do_start,
    	.undo_action = snd_pcm_undo_start,
    	.post_action = snd_pcm_post_start
    };
    
    /**
     * snd_pcm_start - start all linked streams
     * @substream: the PCM substream instance
     */
    int snd_pcm_start(struct snd_pcm_substream *substream)
    {
    	return snd_pcm_action(&snd_pcm_action_start, substream,
    			      SNDRV_PCM_STATE_RUNNING);
    }
    
    /*
     * stop callbacks
     */
    static int snd_pcm_pre_stop(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
    		return -EBADFD;
    	runtime->trigger_master = substream;
    	return 0;
    }
    
    static int snd_pcm_do_stop(struct snd_pcm_substream *substream, int state)
    {
    	if (substream->runtime->trigger_master == substream &&
    	    snd_pcm_running(substream))
    		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
    	return 0; /* unconditonally stop all substreams */
    }
    
    static void snd_pcm_post_stop(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	if (runtime->status->state != state) {
    		snd_pcm_trigger_tstamp(substream);
    		if (substream->timer)
    			snd_timer_notify(substream->timer, SNDRV_TIMER_EVENT_MSTOP,
    					 &runtime->trigger_tstamp);
    		runtime->status->state = state;
    	}
    	wake_up(&runtime->sleep);
    	wake_up(&runtime->tsleep);
    }
    
    static struct action_ops snd_pcm_action_stop = {
    	.pre_action = snd_pcm_pre_stop,
    	.do_action = snd_pcm_do_stop,
    	.post_action = snd_pcm_post_stop
    };
    
    /**
     * snd_pcm_stop - try to stop all running streams in the substream group
     * @substream: the PCM substream instance
     * @state: PCM state after stopping the stream
     *
     * The state of each stream is then changed to the given state unconditionally.
     */
    int snd_pcm_stop(struct snd_pcm_substream *substream, snd_pcm_state_t state)
    {
    	return snd_pcm_action(&snd_pcm_action_stop, substream, state);
    }
    
    EXPORT_SYMBOL(snd_pcm_stop);
    
    /**
     * snd_pcm_drain_done - stop the DMA only when the given stream is playback
     * @substream: the PCM substream
     *
     * After stopping, the state is changed to SETUP.
     * Unlike snd_pcm_stop(), this affects only the given stream.
     */
    int snd_pcm_drain_done(struct snd_pcm_substream *substream)
    {
    	return snd_pcm_action_single(&snd_pcm_action_stop, substream,
    				     SNDRV_PCM_STATE_SETUP);
    }
    
    /*
     * pause callbacks
     */
    static int snd_pcm_pre_pause(struct snd_pcm_substream *substream, int push)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	if (!(runtime->info & SNDRV_PCM_INFO_PAUSE))
    		return -ENOSYS;
    	if (push) {
    		if (runtime->status->state != SNDRV_PCM_STATE_RUNNING)
    			return -EBADFD;
    	} else if (runtime->status->state != SNDRV_PCM_STATE_PAUSED)
    		return -EBADFD;
    	runtime->trigger_master = substream;
    	return 0;
    }
    
    static int snd_pcm_do_pause(struct snd_pcm_substream *substream, int push)
    {
    	if (substream->runtime->trigger_master != substream)
    		return 0;
    	/* some drivers might use hw_ptr to recover from the pause -
    	   update the hw_ptr now */
    	if (push)
    		snd_pcm_update_hw_ptr(substream);
    	/* The jiffies check in snd_pcm_update_hw_ptr*() is done by
    	 * a delta between the current jiffies, this gives a large enough
    	 * delta, effectively to skip the check once.
    	 */
    	substream->runtime->hw_ptr_jiffies = jiffies - HZ * 1000;
    	return substream->ops->trigger(substream,
    				       push ? SNDRV_PCM_TRIGGER_PAUSE_PUSH :
    					      SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
    }
    
    static void snd_pcm_undo_pause(struct snd_pcm_substream *substream, int push)
    {
    	if (substream->runtime->trigger_master == substream)
    		substream->ops->trigger(substream,
    					push ? SNDRV_PCM_TRIGGER_PAUSE_RELEASE :
    					SNDRV_PCM_TRIGGER_PAUSE_PUSH);
    }
    
    static void snd_pcm_post_pause(struct snd_pcm_substream *substream, int push)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	snd_pcm_trigger_tstamp(substream);
    	if (push) {
    		runtime->status->state = SNDRV_PCM_STATE_PAUSED;
    		if (substream->timer)
    			snd_timer_notify(substream->timer,
    					 SNDRV_TIMER_EVENT_MPAUSE,
    					 &runtime->trigger_tstamp);
    		wake_up(&runtime->sleep);
    		wake_up(&runtime->tsleep);
    	} else {
    		runtime->status->state = SNDRV_PCM_STATE_RUNNING;
    		if (substream->timer)
    			snd_timer_notify(substream->timer,
    					 SNDRV_TIMER_EVENT_MCONTINUE,
    					 &runtime->trigger_tstamp);
    	}
    }
    
    static struct action_ops snd_pcm_action_pause = {
    	.pre_action = snd_pcm_pre_pause,
    	.do_action = snd_pcm_do_pause,
    	.undo_action = snd_pcm_undo_pause,
    	.post_action = snd_pcm_post_pause
    };
    
    /*
     * Push/release the pause for all linked streams.
     */
    static int snd_pcm_pause(struct snd_pcm_substream *substream, int push)
    {
    	return snd_pcm_action(&snd_pcm_action_pause, substream, push);
    }
    
    #ifdef CONFIG_PM
    /* suspend */
    
    static int snd_pcm_pre_suspend(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	if (runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
    		return -EBUSY;
    	runtime->trigger_master = substream;
    	return 0;
    }
    
    static int snd_pcm_do_suspend(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	if (runtime->trigger_master != substream)
    		return 0;
    	if (! snd_pcm_running(substream))
    		return 0;
    	substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_SUSPEND);
    	return 0; /* suspend unconditionally */
    }
    
    static void snd_pcm_post_suspend(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	snd_pcm_trigger_tstamp(substream);
    	if (substream->timer)
    		snd_timer_notify(substream->timer, SNDRV_TIMER_EVENT_MSUSPEND,
    				 &runtime->trigger_tstamp);
    	runtime->status->suspended_state = runtime->status->state;
    	runtime->status->state = SNDRV_PCM_STATE_SUSPENDED;
    	wake_up(&runtime->sleep);
    	wake_up(&runtime->tsleep);
    }
    
    static struct action_ops snd_pcm_action_suspend = {
    	.pre_action = snd_pcm_pre_suspend,
    	.do_action = snd_pcm_do_suspend,
    	.post_action = snd_pcm_post_suspend
    };
    
    /**
     * snd_pcm_suspend - trigger SUSPEND to all linked streams
     * @substream: the PCM substream
     *
     * After this call, all streams are changed to SUSPENDED state.
     */
    int snd_pcm_suspend(struct snd_pcm_substream *substream)
    {
    	int err;
    	unsigned long flags;
    
    	if (! substream)
    		return 0;
    
    	snd_pcm_stream_lock_irqsave(substream, flags);
    	err = snd_pcm_action(&snd_pcm_action_suspend, substream, 0);
    	snd_pcm_stream_unlock_irqrestore(substream, flags);
    	return err;
    }
    
    EXPORT_SYMBOL(snd_pcm_suspend);
    
    /**
     * snd_pcm_suspend_all - trigger SUSPEND to all substreams in the given pcm
     * @pcm: the PCM instance
     *
     * After this call, all streams are changed to SUSPENDED state.
     */
    int snd_pcm_suspend_all(struct snd_pcm *pcm)
    {
    	struct snd_pcm_substream *substream;
    	int stream, err = 0;
    
    	if (! pcm)
    		return 0;
    
    	for (stream = 0; stream < 2; stream++) {
    		for (substream = pcm->streams[stream].substream;
    		     substream; substream = substream->next) {
    			/* FIXME: the open/close code should lock this as well */
    			if (substream->runtime == NULL)
    				continue;
    			err = snd_pcm_suspend(substream);
    			if (err < 0 && err != -EBUSY)
    				return err;
    		}
    	}
    	return 0;
    }
    
    EXPORT_SYMBOL(snd_pcm_suspend_all);
    
    /* resume */
    
    static int snd_pcm_pre_resume(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	if (!(runtime->info & SNDRV_PCM_INFO_RESUME))
    		return -ENOSYS;
    	runtime->trigger_master = substream;
    	return 0;
    }
    
    static int snd_pcm_do_resume(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	if (runtime->trigger_master != substream)
    		return 0;
    	/* DMA not running previously? */
    	if (runtime->status->suspended_state != SNDRV_PCM_STATE_RUNNING &&
    	    (runtime->status->suspended_state != SNDRV_PCM_STATE_DRAINING ||
    	     substream->stream != SNDRV_PCM_STREAM_PLAYBACK))
    		return 0;
    	return substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_RESUME);
    }
    
    static void snd_pcm_undo_resume(struct snd_pcm_substream *substream, int state)
    {
    	if (substream->runtime->trigger_master == substream &&
    	    snd_pcm_running(substream))
    		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_SUSPEND);
    }
    
    static void snd_pcm_post_resume(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	snd_pcm_trigger_tstamp(substream);
    	if (substream->timer)
    		snd_timer_notify(substream->timer, SNDRV_TIMER_EVENT_MRESUME,
    				 &runtime->trigger_tstamp);
    	runtime->status->state = runtime->status->suspended_state;
    }
    
    static struct action_ops snd_pcm_action_resume = {
    	.pre_action = snd_pcm_pre_resume,
    	.do_action = snd_pcm_do_resume,
    	.undo_action = snd_pcm_undo_resume,
    	.post_action = snd_pcm_post_resume
    };
    
    static int snd_pcm_resume(struct snd_pcm_substream *substream)
    {
    	struct snd_card *card = substream->pcm->card;
    	int res;
    
    	snd_power_lock(card);
    	if ((res = snd_power_wait(card, SNDRV_CTL_POWER_D0)) >= 0)
    		res = snd_pcm_action_lock_irq(&snd_pcm_action_resume, substream, 0);
    	snd_power_unlock(card);
    	return res;
    }
    
    #else
    
    static int snd_pcm_resume(struct snd_pcm_substream *substream)
    {
    	return -ENOSYS;
    }
    
    #endif /* CONFIG_PM */
    
    /*
     * xrun ioctl
     *
     * Change the RUNNING stream(s) to XRUN state.
     */
    static int snd_pcm_xrun(struct snd_pcm_substream *substream)
    {
    	struct snd_card *card = substream->pcm->card;
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	int result;
    
    	snd_power_lock(card);
    	if (runtime->status->state == SNDRV_PCM_STATE_SUSPENDED) {
    		result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
    		if (result < 0)
    			goto _unlock;
    	}
    
    	snd_pcm_stream_lock_irq(substream);
    	switch (runtime->status->state) {
    	case SNDRV_PCM_STATE_XRUN:
    		result = 0;	/* already there */
    		break;
    	case SNDRV_PCM_STATE_RUNNING:
    		result = snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
    		break;
    	default:
    		result = -EBADFD;
    	}
    	snd_pcm_stream_unlock_irq(substream);
     _unlock:
    	snd_power_unlock(card);
    	return result;
    }
    
    /*
     * reset ioctl
     */
    static int snd_pcm_pre_reset(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	switch (runtime->status->state) {
    	case SNDRV_PCM_STATE_RUNNING:
    	case SNDRV_PCM_STATE_PREPARED:
    	case SNDRV_PCM_STATE_PAUSED:
    	case SNDRV_PCM_STATE_SUSPENDED:
    		return 0;
    	default:
    		return -EBADFD;
    	}
    }
    
    static int snd_pcm_do_reset(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	int err = substream->ops->ioctl(substream, SNDRV_PCM_IOCTL1_RESET, NULL);
    	if (err < 0)
    		return err;
    	runtime->hw_ptr_base = 0;
    	runtime->hw_ptr_interrupt = runtime->status->hw_ptr -
    		runtime->status->hw_ptr % runtime->period_size;
    	runtime->silence_start = runtime->status->hw_ptr;
    	runtime->silence_filled = 0;
    	return 0;
    }
    
    static void snd_pcm_post_reset(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	runtime->control->appl_ptr = runtime->status->hw_ptr;
    	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
    	    runtime->silence_size > 0)
    		snd_pcm_playback_silence(substream, ULONG_MAX);
    }
    
    static struct action_ops snd_pcm_action_reset = {
    	.pre_action = snd_pcm_pre_reset,
    	.do_action = snd_pcm_do_reset,
    	.post_action = snd_pcm_post_reset
    };
    
    static int snd_pcm_reset(struct snd_pcm_substream *substream)
    {
    	return snd_pcm_action_nonatomic(&snd_pcm_action_reset, substream, 0);
    }
    
    /*
     * prepare ioctl
     */
    /* we use the second argument for updating f_flags */
    static int snd_pcm_pre_prepare(struct snd_pcm_substream *substream,
    			       int f_flags)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	if (runtime->status->state == SNDRV_PCM_STATE_OPEN ||
    	    runtime->status->state == SNDRV_PCM_STATE_DISCONNECTED)
    		return -EBADFD;
    	if (snd_pcm_running(substream))
    		return -EBUSY;
    	substream->f_flags = f_flags;
    	return 0;
    }
    
    static int snd_pcm_do_prepare(struct snd_pcm_substream *substream, int state)
    {
    	int err;
    	err = substream->ops->prepare(substream);
    	if (err < 0)
    		return err;
    	return snd_pcm_do_reset(substream, 0);
    }
    
    static void snd_pcm_post_prepare(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	runtime->control->appl_ptr = runtime->status->hw_ptr;
    	runtime->status->state = SNDRV_PCM_STATE_PREPARED;
    }
    
    static struct action_ops snd_pcm_action_prepare = {
    	.pre_action = snd_pcm_pre_prepare,
    	.do_action = snd_pcm_do_prepare,
    	.post_action = snd_pcm_post_prepare
    };
    
    /**
     * snd_pcm_prepare - prepare the PCM substream to be triggerable
     * @substream: the PCM substream instance
     * @file: file to refer f_flags
     */
    static int snd_pcm_prepare(struct snd_pcm_substream *substream,
    			   struct file *file)
    {
    	int res;
    	struct snd_card *card = substream->pcm->card;
    	int f_flags;
    
    	if (file)
    		f_flags = file->f_flags;
    	else
    		f_flags = substream->f_flags;
    
    	snd_power_lock(card);
    	if ((res = snd_power_wait(card, SNDRV_CTL_POWER_D0)) >= 0)
    		res = snd_pcm_action_nonatomic(&snd_pcm_action_prepare,
    					       substream, f_flags);
    	snd_power_unlock(card);
    	return res;
    }
    
    /*
     * drain ioctl
     */
    
    static int snd_pcm_pre_drain_init(struct snd_pcm_substream *substream, int state)
    {
    	substream->runtime->trigger_master = substream;
    	return 0;
    }
    
    static int snd_pcm_do_drain_init(struct snd_pcm_substream *substream, int state)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
    		switch (runtime->status->state) {
    		case SNDRV_PCM_STATE_PREPARED:
    			/* start playback stream if possible */
    			if (! snd_pcm_playback_empty(substream)) {
    				snd_pcm_do_start(substream, SNDRV_PCM_STATE_DRAINING);
    				snd_pcm_post_start(substream, SNDRV_PCM_STATE_DRAINING);
    			}
    			break;
    		case SNDRV_PCM_STATE_RUNNING:
    			runtime->status->state = SNDRV_PCM_STATE_DRAINING;
    			break;
    		default:
    			break;
    		}
    	} else {
    		/* stop running stream */
    		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING) {
    			int new_state = snd_pcm_capture_avail(runtime) > 0 ?
    				SNDRV_PCM_STATE_DRAINING : SNDRV_PCM_STATE_SETUP;
    			snd_pcm_do_stop(substream, new_state);
    			snd_pcm_post_stop(substream, new_state);
    		}
    	}
    	return 0;
    }
    
    static void snd_pcm_post_drain_init(struct snd_pcm_substream *substream, int state)
    {
    }
    
    static struct action_ops snd_pcm_action_drain_init = {
    	.pre_action = snd_pcm_pre_drain_init,
    	.do_action = snd_pcm_do_drain_init,
    	.post_action = snd_pcm_post_drain_init
    };
    
    static int snd_pcm_drop(struct snd_pcm_substream *substream);
    
    /*
     * Drain the stream(s).
     * When the substream is linked, sync until the draining of all playback streams
     * is finished.
     * After this call, all streams are supposed to be either SETUP or DRAINING
     * (capture only) state.
     */
    static int snd_pcm_drain(struct snd_pcm_substream *substream,
    			 struct file *file)
    {
    	struct snd_card *card;
    	struct snd_pcm_runtime *runtime;
    	struct snd_pcm_substream *s;
    	wait_queue_t wait;
    	int result = 0;
    	int nonblock = 0;
    
    	card = substream->pcm->card;
    	runtime = substream->runtime;
    
    	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
    		return -EBADFD;
    
    	snd_power_lock(card);
    	if (runtime->status->state == SNDRV_PCM_STATE_SUSPENDED) {
    		result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
    		if (result < 0) {
    			snd_power_unlock(card);
    			return result;
    		}
    	}
    
    	if (file) {
    		if (file->f_flags & O_NONBLOCK)
    			nonblock = 1;
    	} else if (substream->f_flags & O_NONBLOCK)
    		nonblock = 1;
    
    	down_read(&snd_pcm_link_rwsem);
    	snd_pcm_stream_lock_irq(substream);
    	/* resume pause */
    	if (runtime->status->state == SNDRV_PCM_STATE_PAUSED)
    		snd_pcm_pause(substream, 0);
    
    	/* pre-start/stop - all running streams are changed to DRAINING state */
    	result = snd_pcm_action(&snd_pcm_action_drain_init, substream, 0);
    	if (result < 0)
    		goto unlock;
    	/* in non-blocking, we don't wait in ioctl but let caller poll */
    	if (nonblock) {
    		result = -EAGAIN;
    		goto unlock;
    	}
    
    	for (;;) {
    		long tout;
    		struct snd_pcm_runtime *to_check;
    		if (signal_pending(current)) {
    			result = -ERESTARTSYS;
    			break;
    		}
    		/* find a substream to drain */
    		to_check = NULL;
    		snd_pcm_group_for_each_entry(s, substream) {
    			if (s->stream != SNDRV_PCM_STREAM_PLAYBACK)
    				continue;
    			runtime = s->runtime;
    			if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
    				to_check = runtime;
    				break;
    			}
    		}
    		if (!to_check)
    			break; /* all drained */
    		init_waitqueue_entry(&wait, current);
    		add_wait_queue(&to_check->sleep, &wait);
    		snd_pcm_stream_unlock_irq(substream);
    		up_read(&snd_pcm_link_rwsem);
    		snd_power_unlock(card);
    		if (runtime->no_period_wakeup)
    			tout = MAX_SCHEDULE_TIMEOUT;
    		else {
    			tout = 10;
    			if (runtime->rate) {
    				long t = runtime->period_size * 2 / runtime->rate;
    				tout = max(t, tout);
    			}
    			tout = msecs_to_jiffies(tout * 1000);
    		}
    		tout = schedule_timeout_interruptible(tout);
    		snd_power_lock(card);
    		down_read(&snd_pcm_link_rwsem);
    		snd_pcm_stream_lock_irq(substream);
    		remove_wait_queue(&to_check->sleep, &wait);
    		if (tout == 0) {
    			if (substream->runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
    				result = -ESTRPIPE;
    			else {
    				snd_printd("playback drain error (DMA or IRQ trouble?)\n");
    				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
    				result = -EIO;
    			}
    			break;
    		}
    	}
    
     unlock:
    	snd_pcm_stream_unlock_irq(substream);
    	up_read(&snd_pcm_link_rwsem);
    	snd_power_unlock(card);
    
    	return result;
    }
    
    /*
     * drop ioctl
     *
     * Immediately put all linked substreams into SETUP state.
     */
    static int snd_pcm_drop(struct snd_pcm_substream *substream)
    {
    	struct snd_pcm_runtime *runtime;
    	struct snd_card *card;
    	int result = 0;
    	
    	if (PCM_RUNTIME_CHECK(substream))
    		return -ENXIO;
    	runtime = substream->runtime;
    	card = substream->pcm->card;
    
    	if (runtime->status->state == SNDRV_PCM_STATE_OPEN ||
    	    runtime->status->state == SNDRV_PCM_STATE_DISCONNECTED ||
    	    runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
    		return -EBADFD;
    
    	snd_pcm_stream_lock_irq(substream);
    	/* resume pause */
    	if (runtime->status->state == SNDRV_PCM_STATE_PAUSED)
    		snd_pcm_pause(substream, 0);
    
    	snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
    	/* runtime->control->appl_ptr = runtime->status->hw_ptr; */
    	snd_pcm_stream_unlock_irq(substream);
    
    	return result;
    }
    
    
    /* WARNING: Don't forget to fput back the file */
    static struct file *snd_pcm_file_fd(int fd)
    {
    	struct file *file;
    	struct inode *inode;
    	unsigned int minor;
    
    	file = fget(fd);
    	if (!file)
    		return NULL;
    	inode = file->f_path.dentry->d_inode;
    	if (!S_ISCHR(inode->i_mode) ||
    	    imajor(inode) != snd_major) {
    		fput(file);
    		return NULL;
    	}
    	minor = iminor(inode);
    	if (!snd_lookup_minor_data(minor, SNDRV_DEVICE_TYPE_PCM_PLAYBACK) &&
    	    !snd_lookup_minor_data(minor, SNDRV_DEVICE_TYPE_PCM_CAPTURE)) {
    		fput(file);
    		return NULL;
    	}
    	return file;
    }
    
    /*
     * PCM link handling
     */
    static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
    {
    	int res = 0;
    	struct file *file;
    	struct snd_pcm_file *pcm_file;
    	struct snd_pcm_substream *substream1;
    
    	file = snd_pcm_file_fd(fd);
    	if (!file)
    		return -EBADFD;
    	pcm_file = file->private_data;
    	substream1 = pcm_file->substream;
    	down_write(&snd_pcm_link_rwsem);
    	write_lock_irq(&snd_pcm_link_rwlock);
    	if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN ||
    	    substream->runtime->status->state != substream1->runtime->status->state) {
    		res = -EBADFD;
    		goto _end;
    	}
    	if (snd_pcm_stream_linked(substream1)) {
    		res = -EALREADY;
    		goto _end;
    	}
    	if (!snd_pcm_stream_linked(substream)) {
    		substream->group = kmalloc(sizeof(struct snd_pcm_group), GFP_ATOMIC);
    		if (substream->group == NULL) {
    			res = -ENOMEM;
    			goto _end;
    		}
    		spin_lock_init(&substream->group->lock);
    		INIT_LIST_HEAD(&substream->group->substreams);
    		list_add_tail(&substream->link_list, &substream->group->substreams);
    		substream->group->count = 1;
    	}
    	list_add_tail(&substream1->link_list, &substream->group->substreams);
    	substream->group->count++;
    	substream1->group = substream->group;
     _end:
    	write_unlock_irq(&snd_pcm_link_rwlock);
    	up_write(&snd_pcm_link_rwsem);
    	fput(file);
    	return res;
    }
    
    static void relink_to_local(struct snd_pcm_substream *substream)
    {
    	substream->group = &substream->self_group;
    	INIT_LIST_HEAD(&substream->self_group.substreams);
    	list_add_tail(&substream->link_list, &substream->self_group.substreams);
    }
    
    static int snd_pcm_unlink(struct snd_pcm_substream *substream)
    {
    	struct snd_pcm_substream *s;
    	int res = 0;
    
    	down_write(&snd_pcm_link_rwsem);
    	write_lock_irq(&snd_pcm_link_rwlock);
    	if (!snd_pcm_stream_linked(substream)) {
    		res = -EALREADY;
    		goto _end;
    	}
    	list_del(&substream->link_list);
    	substream->group->count--;
    	if (substream->group->count == 1) {	/* detach the last stream, too */
    		snd_pcm_group_for_each_entry(s, substream) {
    			relink_to_local(s);
    			break;
    		}
    		kfree(substream->group);
    	}
    	relink_to_local(substream);
           _end:
    	write_unlock_irq(&snd_pcm_link_rwlock);
    	up_write(&snd_pcm_link_rwsem);
    	return res;
    }
    
    /*
     * hw configurator
     */
    static int snd_pcm_hw_rule_mul(struct snd_pcm_hw_params *params,
    			       struct snd_pcm_hw_rule *rule)
    {
    	struct snd_interval t;
    	snd_interval_mul(hw_param_interval_c(params, rule->deps[0]),
    		     hw_param_interval_c(params, rule->deps[1]), &t);
    	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
    }
    
    static int snd_pcm_hw_rule_div(struct snd_pcm_hw_params *params,
    			       struct snd_pcm_hw_rule *rule)
    {
    	struct snd_interval t;
    	snd_interval_div(hw_param_interval_c(params, rule->deps[0]),
    		     hw_param_interval_c(params, rule->deps[1]), &t);
    	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
    }
    
    static int snd_pcm_hw_rule_muldivk(struct snd_pcm_hw_params *params,
    				   struct snd_pcm_hw_rule *rule)
    {
    	struct snd_interval t;
    	snd_interval_muldivk(hw_param_interval_c(params, rule->deps[0]),
    			 hw_param_interval_c(params, rule->deps[1]),
    			 (unsigned long) rule->private, &t);
    	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
    }
    
    static int snd_pcm_hw_rule_mulkdiv(struct snd_pcm_hw_params *params,
    				   struct snd_pcm_hw_rule *rule)
    {
    	struct snd_interval t;
    	snd_interval_mulkdiv(hw_param_interval_c(params, rule->deps[0]),
    			 (unsigned long) rule->private,
    			 hw_param_interval_c(params, rule->deps[1]), &t);
    	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
    }
    
    static int snd_pcm_hw_rule_format(struct snd_pcm_hw_params *params,
    				  struct snd_pcm_hw_rule *rule)
    {
    	unsigned int k;
    	struct snd_interval *i = hw_param_interval(params, rule->deps[0]);
    	struct snd_mask m;
    	struct snd_mask *mask = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
    	snd_mask_any(&m);
    	for (k = 0; k <= SNDRV_PCM_FORMAT_LAST; ++k) {
    		int bits;
    		if (! snd_mask_test(mask, k))
    			continue;
    		bits = snd_pcm_format_physical_width(k);
    		if (bits <= 0)
    			continue; /* ignore invalid formats */
    		if ((unsigned)bits < i->min || (unsigned)bits > i->max)
    			snd_mask_reset(&m, k);
    	}
    	return snd_mask_refine(mask, &m);
    }
    
    static int snd_pcm_hw_rule_sample_bits(struct snd_pcm_hw_params *params,
    				       struct snd_pcm_hw_rule *rule)
    {
    	struct snd_interval t;
    	unsigned int k;
    	t.min = UINT_MAX;
    	t.max = 0;
    	t.openmin = 0;
    	t.openmax = 0;
    	for (k = 0; k <= SNDRV_PCM_FORMAT_LAST; ++k) {
    		int bits;
    		if (! snd_mask_test(hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT), k))
    			continue;
    		bits = snd_pcm_format_physical_width(k);
    		if (bits <= 0)
    			continue; /* ignore invalid formats */
    		if (t.min > (unsigned)bits)
    			t.min = bits;
    		if (t.max < (unsigned)bits)
    			t.max = bits;
    	}
    	t.integer = 1;
    	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
    }
    
    #if SNDRV_PCM_RATE_5512 != 1 << 0 || SNDRV_PCM_RATE_192000 != 1 << 12
    #error "Change this table"
    #endif
    
    static unsigned int rates[] = { 5512, 8000, 11025, 16000, 22050, 32000, 44100,
                                     48000, 64000, 88200, 96000, 176400, 192000 };
    
    const struct snd_pcm_hw_constraint_list snd_pcm_known_rates = {
    	.count = ARRAY_SIZE(rates),
    	.list = rates,
    };
    
    static int snd_pcm_hw_rule_rate(struct snd_pcm_hw_params *params,
    				struct snd_pcm_hw_rule *rule)
    {
    	struct snd_pcm_hardware *hw = rule->private;
    	return snd_interval_list(hw_param_interval(params, rule->var),
    				 snd_pcm_known_rates.count,
    				 snd_pcm_known_rates.list, hw->rates);
    }		
    
    static int snd_pcm_hw_rule_buffer_bytes_max(struct snd_pcm_hw_params *params,
    					    struct snd_pcm_hw_rule *rule)
    {
    	struct snd_interval t;
    	struct snd_pcm_substream *substream = rule->private;
    	t.min = 0;
    	t.max = substream->buffer_bytes_max;
    	t.openmin = 0;
    	t.openmax = 0;
    	t.integer = 1;
    	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
    }		
    
    int snd_pcm_hw_constraints_init(struct snd_pcm_substream *substream)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
    	int k, err;
    
    	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++) {
    		snd_mask_any(constrs_mask(constrs, k));
    	}
    
    	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) {
    		snd_interval_any(constrs_interval(constrs, k));
    	}
    
    	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_CHANNELS));
    	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_BUFFER_SIZE));
    	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_BUFFER_BYTES));
    	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_SAMPLE_BITS));
    	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_FRAME_BITS));
    
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
    				   snd_pcm_hw_rule_format, NULL,
    				   SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, 
    				  snd_pcm_hw_rule_sample_bits, NULL,
    				  SNDRV_PCM_HW_PARAM_FORMAT, 
    				  SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, 
    				  snd_pcm_hw_rule_div, NULL,
    				  SNDRV_PCM_HW_PARAM_FRAME_BITS, SNDRV_PCM_HW_PARAM_CHANNELS, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS, 
    				  snd_pcm_hw_rule_mul, NULL,
    				  SNDRV_PCM_HW_PARAM_SAMPLE_BITS, SNDRV_PCM_HW_PARAM_CHANNELS, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS, 
    				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
    				  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS, 
    				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
    				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS, 
    				  snd_pcm_hw_rule_div, NULL,
    				  SNDRV_PCM_HW_PARAM_FRAME_BITS, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE, 
    				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
    				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_PERIOD_TIME, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE, 
    				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
    				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_BUFFER_TIME, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIODS, 
    				  snd_pcm_hw_rule_div, NULL,
    				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 
    				  snd_pcm_hw_rule_div, NULL,
    				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_PERIODS, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 
    				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
    				  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 
    				  snd_pcm_hw_rule_muldivk, (void*) 1000000,
    				  SNDRV_PCM_HW_PARAM_PERIOD_TIME, SNDRV_PCM_HW_PARAM_RATE, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, 
    				  snd_pcm_hw_rule_mul, NULL,
    				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_PERIODS, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, 
    				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
    				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, 
    				  snd_pcm_hw_rule_muldivk, (void*) 1000000,
    				  SNDRV_PCM_HW_PARAM_BUFFER_TIME, SNDRV_PCM_HW_PARAM_RATE, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 
    				  snd_pcm_hw_rule_muldivk, (void*) 8,
    				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 
    				  snd_pcm_hw_rule_muldivk, (void*) 8,
    				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_TIME, 
    				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
    				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_RATE, -1);
    	if (err < 0)
    		return err;
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_TIME, 
    				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
    				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_RATE, -1);
    	if (err < 0)
    		return err;
    	return 0;
    }
    
    int snd_pcm_hw_constraints_complete(struct snd_pcm_substream *substream)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	struct snd_pcm_hardware *hw = &runtime->hw;
    	int err;
    	unsigned int mask = 0;
    
            if (hw->info & SNDRV_PCM_INFO_INTERLEAVED)
    		mask |= 1 << SNDRV_PCM_ACCESS_RW_INTERLEAVED;
            if (hw->info & SNDRV_PCM_INFO_NONINTERLEAVED)
    		mask |= 1 << SNDRV_PCM_ACCESS_RW_NONINTERLEAVED;
    	if (hw->info & SNDRV_PCM_INFO_MMAP) {
    		if (hw->info & SNDRV_PCM_INFO_INTERLEAVED)
    			mask |= 1 << SNDRV_PCM_ACCESS_MMAP_INTERLEAVED;
    		if (hw->info & SNDRV_PCM_INFO_NONINTERLEAVED)
    			mask |= 1 << SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED;
    		if (hw->info & SNDRV_PCM_INFO_COMPLEX)
    			mask |= 1 << SNDRV_PCM_ACCESS_MMAP_COMPLEX;
    	}
    	err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_ACCESS, mask);
    	if (err < 0)
    		return err;
    
    	err = snd_pcm_hw_constraint_mask64(runtime, SNDRV_PCM_HW_PARAM_FORMAT, hw->formats);
    	if (err < 0)
    		return err;
    
    	err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_SUBFORMAT, 1 << SNDRV_PCM_SUBFORMAT_STD);
    	if (err < 0)
    		return err;
    
    	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_CHANNELS,
    					   hw->channels_min, hw->channels_max);
    	if (err < 0)
    		return err;
    
    	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_RATE,
    					   hw->rate_min, hw->rate_max);
    	if (err < 0)
    		return err;
    
    	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
    					   hw->period_bytes_min, hw->period_bytes_max);
    	if (err < 0)
    		return err;
    
    	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIODS,
    					   hw->periods_min, hw->periods_max);
    	if (err < 0)
    		return err;
    
    	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
    					   hw->period_bytes_min, hw->buffer_bytes_max);
    	if (err < 0)
    		return err;
    
    	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 
    				  snd_pcm_hw_rule_buffer_bytes_max, substream,
    				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, -1);
    	if (err < 0)
    		return err;
    
    	/* FIXME: remove */
    	if (runtime->dma_bytes) {
    		err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 0, runtime->dma_bytes);
    		if (err < 0)
    			return -EINVAL;
    	}
    
    	if (!(hw->rates & (SNDRV_PCM_RATE_KNOT | SNDRV_PCM_RATE_CONTINUOUS))) {
    		err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE, 
    					  snd_pcm_hw_rule_rate, hw,
    					  SNDRV_PCM_HW_PARAM_RATE, -1);
    		if (err < 0)
    			return err;
    	}
    
    	/* FIXME: this belong to lowlevel */
    	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
    
    	return 0;
    }
    
    static void pcm_release_private(struct snd_pcm_substream *substream)
    {
    	snd_pcm_unlink(substream);
    }
    
    void snd_pcm_release_substream(struct snd_pcm_substream *substream)
    {
    	substream->ref_count--;
    	if (substream->ref_count > 0)
    		return;
    
    	snd_pcm_drop(substream);
    	if (substream->hw_opened) {
    		if (substream->ops->hw_free != NULL)
    			substream->ops->hw_free(substream);
    		substream->ops->close(substream);
    		substream->hw_opened = 0;
    	}
    	if (pm_qos_request_active(&substream->latency_pm_qos_req))
    		pm_qos_remove_request(&substream->latency_pm_qos_req);
    	if (substream->pcm_release) {
    		substream->pcm_release(substream);
    		substream->pcm_release = NULL;
    	}
    	snd_pcm_detach_substream(substream);
    }
    
    EXPORT_SYMBOL(snd_pcm_release_substream);
    
    int snd_pcm_open_substream(struct snd_pcm *pcm, int stream,
    			   struct file *file,
    			   struct snd_pcm_substream **rsubstream)
    {
    	struct snd_pcm_substream *substream;
    	int err;
    
    	err = snd_pcm_attach_substream(pcm, stream, file, &substream);
    	if (err < 0)
    		return err;
    	if (substream->ref_count > 1) {
    		*rsubstream = substream;
    		return 0;
    	}
    
    	err = snd_pcm_hw_constraints_init(substream);
    	if (err < 0) {
    		snd_printd("snd_pcm_hw_constraints_init failed\n");
    		goto error;
    	}
    
    	if ((err = substream->ops->open(substream)) < 0)
    		goto error;
    
    	substream->hw_opened = 1;
    
    	err = snd_pcm_hw_constraints_complete(substream);
    	if (err < 0) {
    		snd_printd("snd_pcm_hw_constraints_complete failed\n");
    		goto error;
    	}
    
    	*rsubstream = substream;
    	return 0;
    
     error:
    	snd_pcm_release_substream(substream);
    	return err;
    }
    
    EXPORT_SYMBOL(snd_pcm_open_substream);
    
    static int snd_pcm_open_file(struct file *file,
    			     struct snd_pcm *pcm,
    			     int stream,
    			     struct snd_pcm_file **rpcm_file)
    {
    	struct snd_pcm_file *pcm_file;
    	struct snd_pcm_substream *substream;
    	struct snd_pcm_str *str;
    	int err;
    
    	if (rpcm_file)
    		*rpcm_file = NULL;
    
    	err = snd_pcm_open_substream(pcm, stream, file, &substream);
    	if (err < 0)
    		return err;
    
    	pcm_file = kzalloc(sizeof(*pcm_file), GFP_KERNEL);
    	if (pcm_file == NULL) {
    		snd_pcm_release_substream(substream);
    		return -ENOMEM;
    	}
    	pcm_file->substream = substream;
    	if (substream->ref_count == 1) {
    		str = substream->pstr;
    		substream->file = pcm_file;
    		substream->pcm_release = pcm_release_private;
    	}
    	file->private_data = pcm_file;
    	if (rpcm_file)
    		*rpcm_file = pcm_file;
    	return 0;
    }
    
    static int snd_pcm_playback_open(struct inode *inode, struct file *file)
    {
    	struct snd_pcm *pcm;
    	int err = nonseekable_open(inode, file);
    	if (err < 0)
    		return err;
    	pcm = snd_lookup_minor_data(iminor(inode),
    				    SNDRV_DEVICE_TYPE_PCM_PLAYBACK);
    	return snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK);
    }
    
    static int snd_pcm_capture_open(struct inode *inode, struct file *file)
    {
    	struct snd_pcm *pcm;
    	int err = nonseekable_open(inode, file);
    	if (err < 0)
    		return err;
    	pcm = snd_lookup_minor_data(iminor(inode),
    				    SNDRV_DEVICE_TYPE_PCM_CAPTURE);
    	return snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE);
    }
    
    static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream)
    {
    	int err;
    	struct snd_pcm_file *pcm_file;
    	wait_queue_t wait;
    
    	if (pcm == NULL) {
    		err = -ENODEV;
    		goto __error1;
    	}
    	err = snd_card_file_add(pcm->card, file);
    	if (err < 0)
    		goto __error1;
    	if (!try_module_get(pcm->card->module)) {
    		err = -EFAULT;
    		goto __error2;
    	}
    	init_waitqueue_entry(&wait, current);
    	add_wait_queue(&pcm->open_wait, &wait);
    	mutex_lock(&pcm->open_mutex);
    	while (1) {
    		err = snd_pcm_open_file(file, pcm, stream, &pcm_file);
    		if (err >= 0)
    			break;
    		if (err == -EAGAIN) {
    			if (file->f_flags & O_NONBLOCK) {
    				err = -EBUSY;
    				break;
    			}
    		} else
    			break;
    		set_current_state(TASK_INTERRUPTIBLE);
    		mutex_unlock(&pcm->open_mutex);
    		schedule();
    		mutex_lock(&pcm->open_mutex);
    		if (signal_pending(current)) {
    			err = -ERESTARTSYS;
    			break;
    		}
    	}
    	remove_wait_queue(&pcm->open_wait, &wait);
    	mutex_unlock(&pcm->open_mutex);
    	if (err < 0)
    		goto __error;
    	return err;
    
          __error:
    	module_put(pcm->card->module);
          __error2:
          	snd_card_file_remove(pcm->card, file);
          __error1:
          	return err;
    }
    
    static int snd_pcm_release(struct inode *inode, struct file *file)
    {
    	struct snd_pcm *pcm;
    	struct snd_pcm_substream *substream;
    	struct snd_pcm_file *pcm_file;
    
    	pcm_file = file->private_data;
    	substream = pcm_file->substream;
    	if (snd_BUG_ON(!substream))
    		return -ENXIO;
    	pcm = substream->pcm;
    	mutex_lock(&pcm->open_mutex);
    	snd_pcm_release_substream(substream);
    	kfree(pcm_file);
    	mutex_unlock(&pcm->open_mutex);
    	wake_up(&pcm->open_wait);
    	module_put(pcm->card->module);
    	snd_card_file_remove(pcm->card, file);
    	return 0;
    }
    
    static snd_pcm_sframes_t snd_pcm_playback_rewind(struct snd_pcm_substream *substream,
    						 snd_pcm_uframes_t frames)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	snd_pcm_sframes_t appl_ptr;
    	snd_pcm_sframes_t ret;
    	snd_pcm_sframes_t hw_avail;
    
    	if (frames == 0)
    		return 0;
    
    	snd_pcm_stream_lock_irq(substream);
    	switch (runtime->status->state) {
    	case SNDRV_PCM_STATE_PREPARED:
    		break;
    	case SNDRV_PCM_STATE_DRAINING:
    	case SNDRV_PCM_STATE_RUNNING:
    		if (snd_pcm_update_hw_ptr(substream) >= 0)
    			break;
    		/* Fall through */
    	case SNDRV_PCM_STATE_XRUN:
    		ret = -EPIPE;
    		goto __end;
    	case SNDRV_PCM_STATE_SUSPENDED:
    		ret = -ESTRPIPE;
    		goto __end;
    	default:
    		ret = -EBADFD;
    		goto __end;
    	}
    
    	hw_avail = snd_pcm_playback_hw_avail(runtime);
    	if (hw_avail <= 0) {
    		ret = 0;
    		goto __end;
    	}
    	if (frames > (snd_pcm_uframes_t)hw_avail)
    		frames = hw_avail;
    	appl_ptr = runtime->control->appl_ptr - frames;
    	if (appl_ptr < 0)
    		appl_ptr += runtime->boundary;
    	runtime->control->appl_ptr = appl_ptr;
    	ret = frames;
     __end:
    	snd_pcm_stream_unlock_irq(substream);
    	return ret;
    }
    
    static snd_pcm_sframes_t snd_pcm_capture_rewind(struct snd_pcm_substream *substream,
    						snd_pcm_uframes_t frames)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	snd_pcm_sframes_t appl_ptr;
    	snd_pcm_sframes_t ret;
    	snd_pcm_sframes_t hw_avail;
    
    	if (frames == 0)
    		return 0;
    
    	snd_pcm_stream_lock_irq(substream);
    	switch (runtime->status->state) {
    	case SNDRV_PCM_STATE_PREPARED:
    	case SNDRV_PCM_STATE_DRAINING:
    		break;
    	case SNDRV_PCM_STATE_RUNNING:
    		if (snd_pcm_update_hw_ptr(substream) >= 0)
    			break;
    		/* Fall through */
    	case SNDRV_PCM_STATE_XRUN:
    		ret = -EPIPE;
    		goto __end;
    	case SNDRV_PCM_STATE_SUSPENDED:
    		ret = -ESTRPIPE;
    		goto __end;
    	default:
    		ret = -EBADFD;
    		goto __end;
    	}
    
    	hw_avail = snd_pcm_capture_hw_avail(runtime);
    	if (hw_avail <= 0) {
    		ret = 0;
    		goto __end;
    	}
    	if (frames > (snd_pcm_uframes_t)hw_avail)
    		frames = hw_avail;
    	appl_ptr = runtime->control->appl_ptr - frames;
    	if (appl_ptr < 0)
    		appl_ptr += runtime->boundary;
    	runtime->control->appl_ptr = appl_ptr;
    	ret = frames;
     __end:
    	snd_pcm_stream_unlock_irq(substream);
    	return ret;
    }
    
    static snd_pcm_sframes_t snd_pcm_playback_forward(struct snd_pcm_substream *substream,
    						  snd_pcm_uframes_t frames)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	snd_pcm_sframes_t appl_ptr;
    	snd_pcm_sframes_t ret;
    	snd_pcm_sframes_t avail;
    
    	if (frames == 0)
    		return 0;
    
    	snd_pcm_stream_lock_irq(substream);
    	switch (runtime->status->state) {
    	case SNDRV_PCM_STATE_PREPARED:
    	case SNDRV_PCM_STATE_PAUSED:
    		break;
    	case SNDRV_PCM_STATE_DRAINING:
    	case SNDRV_PCM_STATE_RUNNING:
    		if (snd_pcm_update_hw_ptr(substream) >= 0)
    			break;
    		/* Fall through */
    	case SNDRV_PCM_STATE_XRUN:
    		ret = -EPIPE;
    		goto __end;
    	case SNDRV_PCM_STATE_SUSPENDED:
    		ret = -ESTRPIPE;
    		goto __end;
    	default:
    		ret = -EBADFD;
    		goto __end;
    	}
    
    	avail = snd_pcm_playback_avail(runtime);
    	if (avail <= 0) {
    		ret = 0;
    		goto __end;
    	}
    	if (frames > (snd_pcm_uframes_t)avail)
    		frames = avail;
    	appl_ptr = runtime->control->appl_ptr + frames;
    	if (appl_ptr >= (snd_pcm_sframes_t)runtime->boundary)
    		appl_ptr -= runtime->boundary;
    	runtime->control->appl_ptr = appl_ptr;
    	ret = frames;
     __end:
    	snd_pcm_stream_unlock_irq(substream);
    	return ret;
    }
    
    static snd_pcm_sframes_t snd_pcm_capture_forward(struct snd_pcm_substream *substream,
    						 snd_pcm_uframes_t frames)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	snd_pcm_sframes_t appl_ptr;
    	snd_pcm_sframes_t ret;
    	snd_pcm_sframes_t avail;
    
    	if (frames == 0)
    		return 0;
    
    	snd_pcm_stream_lock_irq(substream);
    	switch (runtime->status->state) {
    	case SNDRV_PCM_STATE_PREPARED:
    	case SNDRV_PCM_STATE_DRAINING:
    	case SNDRV_PCM_STATE_PAUSED:
    		break;
    	case SNDRV_PCM_STATE_RUNNING:
    		if (snd_pcm_update_hw_ptr(substream) >= 0)
    			break;
    		/* Fall through */
    	case SNDRV_PCM_STATE_XRUN:
    		ret = -EPIPE;
    		goto __end;
    	case SNDRV_PCM_STATE_SUSPENDED:
    		ret = -ESTRPIPE;
    		goto __end;
    	default:
    		ret = -EBADFD;
    		goto __end;
    	}
    
    	avail = snd_pcm_capture_avail(runtime);
    	if (avail <= 0) {
    		ret = 0;
    		goto __end;
    	}
    	if (frames > (snd_pcm_uframes_t)avail)
    		frames = avail;
    	appl_ptr = runtime->control->appl_ptr + frames;
    	if (appl_ptr >= (snd_pcm_sframes_t)runtime->boundary)
    		appl_ptr -= runtime->boundary;
    	runtime->control->appl_ptr = appl_ptr;
    	ret = frames;
     __end:
    	snd_pcm_stream_unlock_irq(substream);
    	return ret;
    }
    
    static int snd_pcm_hwsync(struct snd_pcm_substream *substream)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	int err;
    
    	snd_pcm_stream_lock_irq(substream);
    	switch (runtime->status->state) {
    	case SNDRV_PCM_STATE_DRAINING:
    		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
    			goto __badfd;
    	case SNDRV_PCM_STATE_RUNNING:
    		if ((err = snd_pcm_update_hw_ptr(substream)) < 0)
    			break;
    		/* Fall through */
    	case SNDRV_PCM_STATE_PREPARED:
    	case SNDRV_PCM_STATE_SUSPENDED:
    		err = 0;
    		break;
    	case SNDRV_PCM_STATE_XRUN:
    		err = -EPIPE;
    		break;
    	default:
    	      __badfd:
    		err = -EBADFD;
    		break;
    	}
    	snd_pcm_stream_unlock_irq(substream);
    	return err;
    }
    		
    static int snd_pcm_delay(struct snd_pcm_substream *substream,
    			 snd_pcm_sframes_t __user *res)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	int err;
    	snd_pcm_sframes_t n = 0;
    
    	snd_pcm_stream_lock_irq(substream);
    	switch (runtime->status->state) {
    	case SNDRV_PCM_STATE_DRAINING:
    		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
    			goto __badfd;
    	case SNDRV_PCM_STATE_RUNNING:
    		if ((err = snd_pcm_update_hw_ptr(substream)) < 0)
    			break;
    		/* Fall through */
    	case SNDRV_PCM_STATE_PREPARED:
    	case SNDRV_PCM_STATE_SUSPENDED:
    		err = 0;
    		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
    			n = snd_pcm_playback_hw_avail(runtime);
    		else
    			n = snd_pcm_capture_avail(runtime);
    		n += runtime->delay;
    		break;
    	case SNDRV_PCM_STATE_XRUN:
    		err = -EPIPE;
    		break;
    	default:
    	      __badfd:
    		err = -EBADFD;
    		break;
    	}
    	snd_pcm_stream_unlock_irq(substream);
    	if (!err)
    		if (put_user(n, res))
    			err = -EFAULT;
    	return err;
    }
    		
    static int snd_pcm_sync_ptr(struct snd_pcm_substream *substream,
    			    struct snd_pcm_sync_ptr __user *_sync_ptr)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	struct snd_pcm_sync_ptr sync_ptr;
    	volatile struct snd_pcm_mmap_status *status;
    	volatile struct snd_pcm_mmap_control *control;
    	int err;
    
    	memset(&sync_ptr, 0, sizeof(sync_ptr));
    	if (get_user(sync_ptr.flags, (unsigned __user *)&(_sync_ptr->flags)))
    		return -EFAULT;
    	if (copy_from_user(&sync_ptr.c.control, &(_sync_ptr->c.control), sizeof(struct snd_pcm_mmap_control)))
    		return -EFAULT;	
    	status = runtime->status;
    	control = runtime->control;
    	if (sync_ptr.flags & SNDRV_PCM_SYNC_PTR_HWSYNC) {
    		err = snd_pcm_hwsync(substream);
    		if (err < 0)
    			return err;
    	}
    	snd_pcm_stream_lock_irq(substream);
    	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_APPL))
    		control->appl_ptr = sync_ptr.c.control.appl_ptr;
    	else
    		sync_ptr.c.control.appl_ptr = control->appl_ptr;
    	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_AVAIL_MIN))
    		control->avail_min = sync_ptr.c.control.avail_min;
    	else
    		sync_ptr.c.control.avail_min = control->avail_min;
    	sync_ptr.s.status.state = status->state;
    	sync_ptr.s.status.hw_ptr = status->hw_ptr;
    	sync_ptr.s.status.tstamp = status->tstamp;
    	sync_ptr.s.status.suspended_state = status->suspended_state;
    	snd_pcm_stream_unlock_irq(substream);
    	if (copy_to_user(_sync_ptr, &sync_ptr, sizeof(sync_ptr)))
    		return -EFAULT;
    	return 0;
    }
    
    static int snd_pcm_tstamp(struct snd_pcm_substream *substream, int __user *_arg)
    {
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	int arg;
    	
    	if (get_user(arg, _arg))
    		return -EFAULT;
    	if (arg < 0 || arg > SNDRV_PCM_TSTAMP_TYPE_LAST)
    		return -EINVAL;
    	runtime->tstamp_type = SNDRV_PCM_TSTAMP_TYPE_GETTIMEOFDAY;
    	if (arg == SNDRV_PCM_TSTAMP_TYPE_MONOTONIC)
    		runtime->tstamp_type = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC;
    	return 0;
    }
    		
    static int snd_pcm_common_ioctl1(struct file *file,
    				 struct snd_pcm_substream *substream,
    				 unsigned int cmd, void __user *arg)
    {
    	switch (cmd) {
    	case SNDRV_PCM_IOCTL_PVERSION:
    		return put_user(SNDRV_PCM_VERSION, (int __user *)arg) ? -EFAULT : 0;
    	case SNDRV_PCM_IOCTL_INFO:
    		return snd_pcm_info_user(substream, arg);
    	case SNDRV_PCM_IOCTL_TSTAMP:	/* just for compatibility */
    		return 0;
    	case SNDRV_PCM_IOCTL_TTSTAMP:
    		return snd_pcm_tstamp(substream, arg);
    	case SNDRV_PCM_IOCTL_HW_REFINE:
    		return snd_pcm_hw_refine_user(substream, arg);
    	case SNDRV_PCM_IOCTL_HW_PARAMS:
    		return snd_pcm_hw_params_user(substream, arg);
    	case SNDRV_PCM_IOCTL_HW_FREE:
    		return snd_pcm_hw_free(substream);
    	case SNDRV_PCM_IOCTL_SW_PARAMS:
    		return snd_pcm_sw_params_user(substream, arg);
    	case SNDRV_PCM_IOCTL_STATUS:
    		return snd_pcm_status_user(substream, arg);
    	case SNDRV_PCM_IOCTL_CHANNEL_INFO:
    		return snd_pcm_channel_info_user(substream, arg);
    	case SNDRV_PCM_IOCTL_PREPARE:
    		return snd_pcm_prepare(substream, file);
    	case SNDRV_PCM_IOCTL_RESET:
    		return snd_pcm_reset(substream);
    	case SNDRV_PCM_IOCTL_START:
    		return snd_pcm_action_lock_irq(&snd_pcm_action_start, substream, SNDRV_PCM_STATE_RUNNING);
    	case SNDRV_PCM_IOCTL_LINK:
    		return snd_pcm_link(substream, (int)(unsigned long) arg);
    	case SNDRV_PCM_IOCTL_UNLINK:
    		return snd_pcm_unlink(substream);
    	case SNDRV_PCM_IOCTL_RESUME:
    		return snd_pcm_resume(substream);
    	case SNDRV_PCM_IOCTL_XRUN:
    		return snd_pcm_xrun(substream);
    	case SNDRV_PCM_IOCTL_HWSYNC:
    		return snd_pcm_hwsync(substream);
    	case SNDRV_PCM_IOCTL_DELAY:
    		return snd_pcm_delay(substream, arg);
    	case SNDRV_PCM_IOCTL_SYNC_PTR:
    		return snd_pcm_sync_ptr(substream, arg);
    #ifdef CONFIG_SND_SUPPORT_OLD_API
    	case SNDRV_PCM_IOCTL_HW_REFINE_OLD:
    		return snd_pcm_hw_refine_old_user(substream, arg);
    	case SNDRV_PCM_IOCTL_HW_PARAMS_OLD:
    		return snd_pcm_hw_params_old_user(substream, arg);
    #endif
    	case SNDRV_PCM_IOCTL_DRAIN:
    		return snd_pcm_drain(substream, file);
    	case SNDRV_PCM_IOCTL_DROP:
    		return snd_pcm_drop(substream);
    	case SNDRV_PCM_IOCTL_PAUSE:
    	{
    		int res;
    		snd_pcm_stream_lock_irq(substream);
    		res = snd_pcm_pause(substream, (int)(unsigned long)arg);
    		snd_pcm_stream_unlock_irq(substream);
    		return res;
    	}
    	}
    	snd_printd("unknown ioctl = 0x%x\n", cmd);
    	return -ENOTTY;
    }
    
    static int snd_pcm_playback_ioctl1(struct file *file,
    				   struct snd_pcm_substream *substream,
    				   unsigned int cmd, void __user *arg)
    {
    	if (snd_BUG_ON(!substream))
    		return -ENXIO;
    	if (snd_BUG_ON(substream->stream != SNDRV_PCM_STREAM_PLAYBACK))
    		return -EINVAL;
    	switch (cmd) {
    	case SNDRV_PCM_IOCTL_WRITEI_FRAMES:
    	{
    		struct snd_xferi xferi;
    		struct snd_xferi __user *_xferi = arg;
    		struct snd_pcm_runtime *runtime = substream->runtime;
    		snd_pcm_sframes_t result;
    		if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
    			return -EBADFD;
    		if (put_user(0, &_xferi->result))
    			return -EFAULT;
    		if (copy_from_user(&xferi, _xferi, sizeof(xferi)))
    			return -EFAULT;
    		result = snd_pcm_lib_write(substream, xferi.buf, xferi.frames);
    		__put_user(result, &_xferi->result);
    		return result < 0 ? result : 0;
    	}
    	case SNDRV_PCM_IOCTL_WRITEN_FRAMES:
    	{
    		struct snd_xfern xfern;
    		struct snd_xfern __user *_xfern = arg;
    		struct snd_pcm_runtime *runtime = substream->runtime;
    		void __user **bufs;
    		snd_pcm_sframes_t result;
    		if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
    			return -EBADFD;
    		if (runtime->channels > 128)
    			return -EINVAL;
    		if (put_user(0, &_xfern->result))
    			return -EFAULT;
    		if (copy_from_user(&xfern, _xfern, sizeof(xfern)))
    			return -EFAULT;
    
    		bufs = memdup_user(xfern.bufs,
    				   sizeof(void *) * runtime->channels);
    		if (IS_ERR(bufs))
    			return PTR_ERR(bufs);
    		result = snd_pcm_lib_writev(substream, bufs, xfern.frames);
    		kfree(bufs);
    		__put_user(result, &_xfern->result);
    		return result < 0 ? result : 0;
    	}
    	case SNDRV_PCM_IOCTL_REWIND:
    	{
    		snd_pcm_uframes_t frames;
    		snd_pcm_uframes_t __user *_frames = arg;
    		snd_pcm_sframes_t result;
    		if (get_user(frames, _frames))
    			return -EFAULT;
    		if (put_user(0, _frames))
    			return -EFAULT;
    		result = snd_pcm_playback_rewind(substream, frames);
    		__put_user(result, _frames);
    		return result < 0 ? result : 0;
    	}
    	case SNDRV_PCM_IOCTL_FORWARD:
    	{
    		snd_pcm_uframes_t frames;
    		snd_pcm_uframes_t __user *_frames = arg;
    		snd_pcm_sframes_t result;
    		if (get_user(frames, _frames))
    			return -EFAULT;
    		if (put_user(0, _frames))
    			return -EFAULT;
    		result = snd_pcm_playback_forward(substream, frames);
    		__put_user(result, _frames);
    		return result < 0 ? result : 0;
    	}
    	}
    	return snd_pcm_common_ioctl1(file, substream, cmd, arg);
    }
    
    static int snd_pcm_capture_ioctl1(struct file *file,
    				  struct snd_pcm_substream *substream,
    				  unsigned int cmd, void __user *arg)
    {
    	if (snd_BUG_ON(!substream))
    		return -ENXIO;
    	if (snd_BUG_ON(substream->stream != SNDRV_PCM_STREAM_CAPTURE))
    		return -EINVAL;
    	switch (cmd) {
    	case SNDRV_PCM_IOCTL_READI_FRAMES:
    	{
    		struct snd_xferi xferi;
    		struct snd_xferi __user *_xferi = arg;
    		struct snd_pcm_runtime *runtime = substream->runtime;
    		snd_pcm_sframes_t result;
    		if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
    			return -EBADFD;
    		if (put_user(0, &_xferi->result))
    			return -EFAULT;
    		if (copy_from_user(&xferi, _xferi, sizeof(xferi)))
    			return -EFAULT;
    		result = snd_pcm_lib_read(substream, xferi.buf, xferi.frames);
    		__put_user(result, &_xferi->result);
    		return result < 0 ? result : 0;
    	}
    	case SNDRV_PCM_IOCTL_READN_FRAMES:
    	{
    		struct snd_xfern xfern;
    		struct snd_xfern __user *_xfern = arg;
    		struct snd_pcm_runtime *runtime = substream->runtime;
    		void *bufs;
    		snd_pcm_sframes_t result;
    		if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
    			return -EBADFD;
    		if (runtime->channels > 128)
    			return -EINVAL;
    		if (put_user(0, &_xfern->result))
    			return -EFAULT;
    		if (copy_from_user(&xfern, _xfern, sizeof(xfern)))
    			return -EFAULT;
    
    		bufs = memdup_user(xfern.bufs,
    				   sizeof(void *) * runtime->channels);
    		if (IS_ERR(bufs))
    			return PTR_ERR(bufs);
    		result = snd_pcm_lib_readv(substream, bufs, xfern.frames);
    		kfree(bufs);
    		__put_user(result, &_xfern->result);
    		return result < 0 ? result : 0;
    	}
    	case SNDRV_PCM_IOCTL_REWIND:
    	{
    		snd_pcm_uframes_t frames;
    		snd_pcm_uframes_t __user *_frames = arg;
    		snd_pcm_sframes_t result;
    		if (get_user(frames, _frames))
    			return -EFAULT;
    		if (put_user(0, _frames))
    			return -EFAULT;
    		result = snd_pcm_capture_rewind(substream, frames);
    		__put_user(result, _frames);
    		return result < 0 ? result : 0;
    	}
    	case SNDRV_PCM_IOCTL_FORWARD:
    	{
    		snd_pcm_uframes_t frames;
    		snd_pcm_uframes_t __user *_frames = arg;
    		snd_pcm_sframes_t result;
    		if (get_user(frames, _frames))
    			return -EFAULT;
    		if (put_user(0, _frames))
    			return -EFAULT;
    		result = snd_pcm_capture_forward(substream, frames);
    		__put_user(result, _frames);
    		return result < 0 ? result : 0;
    	}
    	}
    	return snd_pcm_common_ioctl1(file, substream, cmd, arg);
    }
    
    static long snd_pcm_playback_ioctl(struct file *file, unsigned int cmd,
    				   unsigned long arg)
    {
    	struct snd_pcm_file *pcm_file;
    
    	pcm_file = file->private_data;
    
    	if (((cmd >> 8) & 0xff) != 'A')
    		return -ENOTTY;
    
    	return snd_pcm_playback_ioctl1(file, pcm_file->substream, cmd,
    				       (void __user *)arg);
    }
    
    static long snd_pcm_capture_ioctl(struct file *file, unsigned int cmd,
    				  unsigned long arg)
    {
    	struct snd_pcm_file *pcm_file;
    
    	pcm_file = file->private_data;
    
    	if (((cmd >> 8) & 0xff) != 'A')
    		return -ENOTTY;
    
    	return snd_pcm_capture_ioctl1(file, pcm_file->substream, cmd,
    				      (void __user *)arg);
    }
    
    int snd_pcm_kernel_ioctl(struct snd_pcm_substream *substream,
    			 unsigned int cmd, void *arg)
    {
    	mm_segment_t fs;
    	int result;
    	
    	fs = snd_enter_user();
    	switch (substream->stream) {
    	case SNDRV_PCM_STREAM_PLAYBACK:
    		result = snd_pcm_playback_ioctl1(NULL, substream, cmd,
    						 (void __user *)arg);
    		break;
    	case SNDRV_PCM_STREAM_CAPTURE:
    		result = snd_pcm_capture_ioctl1(NULL, substream, cmd,
    						(void __user *)arg);
    		break;
    	default:
    		result = -EINVAL;
    		break;
    	}
    	snd_leave_user(fs);
    	return result;
    }
    
    EXPORT_SYMBOL(snd_pcm_kernel_ioctl);
    
    static ssize_t snd_pcm_read(struct file *file, char __user *buf, size_t count,
    			    loff_t * offset)
    {
    	struct snd_pcm_file *pcm_file;
    	struct snd_pcm_substream *substream;
    	struct snd_pcm_runtime *runtime;
    	snd_pcm_sframes_t result;
    
    	pcm_file = file->private_data;
    	substream = pcm_file->substream;
    	if (PCM_RUNTIME_CHECK(substream))
    		return -ENXIO;
    	runtime = substream->runtime;
    	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
    		return -EBADFD;
    	if (!frame_aligned(runtime, count))
    		return -EINVAL;
    	count = bytes_to_frames(runtime, count);
    	result = snd_pcm_lib_read(substream, buf, count);
    	if (result > 0)
    		result = frames_to_bytes(runtime, result);
    	return result;
    }
    
    static ssize_t snd_pcm_write(struct file *file, const char __user *buf,
    			     size_t count, loff_t * offset)
    {
    	struct snd_pcm_file *pcm_file;
    	struct snd_pcm_substream *substream;
    	struct snd_pcm_runtime *runtime;
    	snd_pcm_sframes_t result;
    
    	pcm_file = file->private_data;
    	substream = pcm_file->substream;
    	if (PCM_RUNTIME_CHECK(substream))
    		return -ENXIO;
    	runtime = substream->runtime;
    	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
    		return -EBADFD;
    	if (!frame_aligned(runtime, count))
    		return -EINVAL;
    	count = bytes_to_frames(runtime, count);
    	result = snd_pcm_lib_write(substream, buf, count);
    	if (result > 0)
    		result = frames_to_bytes(runtime, result);
    	return result;
    }
    
    static ssize_t snd_pcm_aio_read(struct kiocb *iocb, const struct iovec *iov,
    			     unsigned long nr_segs, loff_t pos)
    
    {
    	struct snd_pcm_file *pcm_file;
    	struct snd_pcm_substream *substream;
    	struct snd_pcm_runtime *runtime;
    	snd_pcm_sframes_t result;
    	unsigned long i;
    	void __user **bufs;
    	snd_pcm_uframes_t frames;
    
    	pcm_file = iocb->ki_filp->private_data;
    	substream = pcm_file->substream;
    	if (PCM_RUNTIME_CHECK(substream))
    		return -ENXIO;
    	runtime = substream->runtime;
    	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
    		return -EBADFD;
    	if (nr_segs > 1024 || nr_segs != runtime->channels)
    		return -EINVAL;
    	if (!frame_aligned(runtime, iov->iov_len))
    		return -EINVAL;
    	frames = bytes_to_samples(runtime, iov->iov_len);
    	bufs = kmalloc(sizeof(void *) * nr_segs, GFP_KERNEL);
    	if (bufs == NULL)
    		return -ENOMEM;
    	for (i = 0; i < nr_segs; ++i)
    		bufs[i] = iov[i].iov_base;
    	result = snd_pcm_lib_readv(substream, bufs, frames);
    	if (result > 0)
    		result = frames_to_bytes(runtime, result);
    	kfree(bufs);
    	return result;
    }
    
    static ssize_t snd_pcm_aio_write(struct kiocb *iocb, const struct iovec *iov,
    			      unsigned long nr_segs, loff_t pos)
    {
    	struct snd_pcm_file *pcm_file;
    	struct snd_pcm_substream *substream;
    	struct snd_pcm_runtime *runtime;
    	snd_pcm_sframes_t result;
    	unsigned long i;
    	void __user **bufs;
    	snd_pcm_uframes_t frames;
    
    	pcm_file = iocb->ki_filp->private_data;
    	substream = pcm_file->substream;
    	if (PCM_RUNTIME_CHECK(substream))
    		return -ENXIO;
    	runtime = substream->runtime;
    	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
    		return -EBADFD;
    	if (nr_segs > 128 || nr_segs != runtime->channels ||
    	    !frame_aligned(runtime, iov->iov_len))
    		return -EINVAL;
    	frames = bytes_to_samples(runtime, iov->iov_len);
    	bufs = kmalloc(sizeof(void *) * nr_segs, GFP_KERNEL);
    	if (bufs == NULL)
    		return -ENOMEM;
    	for (i = 0; i < nr_segs; ++i)
    		bufs[i] = iov[i].iov_base;
    	result = snd_pcm_lib_writev(substream, bufs, frames);
    	if (result > 0)
    		result = frames_to_bytes(runtime, result);
    	kfree(bufs);
    	return result;
    }
    
    static unsigned int snd_pcm_playback_poll(struct file *file, poll_table * wait)
    {
    	struct snd_pcm_file *pcm_file;
    	struct snd_pcm_substream *substream;
    	struct snd_pcm_runtime *runtime;
            unsigned int mask;
    	snd_pcm_uframes_t avail;
    
    	pcm_file = file->private_data;
    
    	substream = pcm_file->substream;
    	if (PCM_RUNTIME_CHECK(substream))
    		return -ENXIO;
    	runtime = substream->runtime;
    
    	poll_wait(file, &runtime->sleep, wait);
    
    	snd_pcm_stream_lock_irq(substream);
    	avail = snd_pcm_playback_avail(runtime);
    	switch (runtime->status->state) {
    	case SNDRV_PCM_STATE_RUNNING:
    	case SNDRV_PCM_STATE_PREPARED:
    	case SNDRV_PCM_STATE_PAUSED:
    		if (avail >= runtime->control->avail_min) {
    			mask = POLLOUT | POLLWRNORM;
    			break;
    		}
    		/* Fall through */
    	case SNDRV_PCM_STATE_DRAINING:
    		mask = 0;
    		break;
    	default:
    		mask = POLLOUT | POLLWRNORM | POLLERR;
    		break;
    	}
    	snd_pcm_stream_unlock_irq(substream);
    	return mask;
    }
    
    static unsigned int snd_pcm_capture_poll(struct file *file, poll_table * wait)
    {
    	struct snd_pcm_file *pcm_file;
    	struct snd_pcm_substream *substream;
    	struct snd_pcm_runtime *runtime;
            unsigned int mask;
    	snd_pcm_uframes_t avail;
    
    	pcm_file = file->private_data;
    
    	substream = pcm_file->substream;
    	if (PCM_RUNTIME_CHECK(substream))
    		return -ENXIO;
    	runtime = substream->runtime;
    
    	poll_wait(file, &runtime->sleep, wait);
    
    	snd_pcm_stream_lock_irq(substream);
    	avail = snd_pcm_capture_avail(runtime);
    	switch (runtime->status->state) {
    	case SNDRV_PCM_STATE_RUNNING:
    	case SNDRV_PCM_STATE_PREPARED:
    	case SNDRV_PCM_STATE_PAUSED:
    		if (avail >= runtime->control->avail_min) {
    			mask = POLLIN | POLLRDNORM;
    			break;
    		}
    		mask = 0;
    		break;
    	case SNDRV_PCM_STATE_DRAINING:
    		if (avail > 0) {
    			mask = POLLIN | POLLRDNORM;
    			break;
    		}
    		/* Fall through */
    	default:
    		mask = POLLIN | POLLRDNORM | POLLERR;
    		break;
    	}
    	snd_pcm_stream_unlock_irq(substream);
    	return mask;
    }
    
    /*
     * mmap support
     */
    
    /*
     * Only on coherent architectures, we can mmap the status and the control records
     * for effcient data transfer.  On others, we have to use HWSYNC ioctl...
     */
    #if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_ALPHA)
    /*
     * mmap status record
     */
    static int snd_pcm_mmap_status_fault(struct vm_area_struct *area,
    						struct vm_fault *vmf)
    {
    	struct snd_pcm_substream *substream = area->vm_private_data;
    	struct snd_pcm_runtime *runtime;
    	
    	if (substream == NULL)
    		return VM_FAULT_SIGBUS;
    	runtime = substream->runtime;
    	vmf->page = virt_to_page(runtime->status);
    	get_page(vmf->page);
    	return 0;
    }
    
    static const struct vm_operations_struct snd_pcm_vm_ops_status =
    {
    	.fault =	snd_pcm_mmap_status_fault,
    };
    
    static int snd_pcm_mmap_status(struct snd_pcm_substream *substream, struct file *file,
    			       struct vm_area_struct *area)
    {
    	struct snd_pcm_runtime *runtime;
    	long size;
    	if (!(area->vm_flags & VM_READ))
    		return -EINVAL;
    	runtime = substream->runtime;
    	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 int snd_pcm_mmap_control_fault(struct vm_area_struct *area,
    						struct vm_fault *vmf)
    {
    	struct snd_pcm_substream *substream = area->vm_private_data;
    	struct snd_pcm_runtime *runtime;
    	
    	if (substream == NULL)
    		return VM_FAULT_SIGBUS;
    	runtime = substream->runtime;
    	vmf->page = virt_to_page(runtime->control);
    	get_page(vmf->page);
    	return 0;
    }
    
    static const struct vm_operations_struct snd_pcm_vm_ops_control =
    {
    	.fault =	snd_pcm_mmap_control_fault,
    };
    
    static int snd_pcm_mmap_control(struct snd_pcm_substream *substream, struct file *file,
    				struct vm_area_struct *area)
    {
    	struct snd_pcm_runtime *runtime;
    	long size;
    	if (!(area->vm_flags & VM_READ))
    		return -EINVAL;
    	runtime = substream->runtime;
    	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 */
    
    static inline struct page *
    snd_pcm_default_page_ops(struct snd_pcm_substream *substream, unsigned long ofs)
    {
    	void *vaddr = substream->runtime->dma_area + ofs;
    #if defined(CONFIG_MIPS) && defined(CONFIG_DMA_NONCOHERENT)
    	if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV)
    		return virt_to_page(CAC_ADDR(vaddr));
    #endif
    #if defined(CONFIG_PPC32) && defined(CONFIG_NOT_COHERENT_CACHE)
    	if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV) {
    		dma_addr_t addr = substream->runtime->dma_addr + ofs;
    		addr -= get_dma_offset(substream->dma_buffer.dev.dev);
    		/* assume dma_handle set via pfn_to_phys() in
    		 * mm/dma-noncoherent.c
    		 */
    		return pfn_to_page(addr >> PAGE_SHIFT);
    	}
    #endif
    	return virt_to_page(vaddr);
    }
    
    /*
     * fault callback for mmapping a RAM page
     */
    static int snd_pcm_mmap_data_fault(struct vm_area_struct *area,
    						struct vm_fault *vmf)
    {
    	struct snd_pcm_substream *substream = area->vm_private_data;
    	struct snd_pcm_runtime *runtime;
    	unsigned long offset;
    	struct page * page;
    	size_t dma_bytes;
    	
    	if (substream == NULL)
    		return VM_FAULT_SIGBUS;
    	runtime = substream->runtime;
    	offset = vmf->pgoff << PAGE_SHIFT;
    	dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
    	if (offset > dma_bytes - PAGE_SIZE)
    		return VM_FAULT_SIGBUS;
    	if (substream->ops->page)
    		page = substream->ops->page(substream, offset);
    	else
    		page = snd_pcm_default_page_ops(substream, offset);
    	if (!page)
    		return VM_FAULT_SIGBUS;
    	get_page(page);
    	vmf->page = page;
    	return 0;
    }
    
    static const struct vm_operations_struct snd_pcm_vm_ops_data = {
    	.open =		snd_pcm_mmap_data_open,
    	.close =	snd_pcm_mmap_data_close,
    };
    
    static const struct vm_operations_struct snd_pcm_vm_ops_data_fault = {
    	.open =		snd_pcm_mmap_data_open,
    	.close =	snd_pcm_mmap_data_close,
    	.fault =	snd_pcm_mmap_data_fault,
    };
    
    #ifndef ARCH_HAS_DMA_MMAP_COHERENT
    /* This should be defined / handled globally! */
    #ifdef CONFIG_ARM
    #define ARCH_HAS_DMA_MMAP_COHERENT
    #endif
    #endif
    
    /*
     * mmap the DMA buffer on RAM
     */
    static int snd_pcm_default_mmap(struct snd_pcm_substream *substream,
    				struct vm_area_struct *area)
    {
    	area->vm_flags |= VM_RESERVED;
    #ifdef ARCH_HAS_DMA_MMAP_COHERENT
    	if (!substream->ops->page &&
    	    substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV)
    		return dma_mmap_coherent(substream->dma_buffer.dev.dev,
    					 area,
    					 substream->runtime->dma_area,
    					 substream->runtime->dma_addr,
    					 area->vm_end - area->vm_start);
    #elif defined(CONFIG_MIPS) && defined(CONFIG_DMA_NONCOHERENT)
    	if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV &&
    	    !plat_device_is_coherent(substream->dma_buffer.dev.dev))
    		area->vm_page_prot = pgprot_noncached(area->vm_page_prot);
    #endif /* ARCH_HAS_DMA_MMAP_COHERENT */
    	/* mmap with fault handler */
    	area->vm_ops = &snd_pcm_vm_ops_data_fault;
    	return 0;
    }
    
    /*
     * mmap the DMA buffer on I/O memory area
     */
    #if SNDRV_PCM_INFO_MMAP_IOMEM
    int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream,
    			   struct vm_area_struct *area)
    {
    	long size;
    	unsigned long offset;
    
    	area->vm_page_prot = pgprot_noncached(area->vm_page_prot);
    	area->vm_flags |= VM_IO;
    	size = area->vm_end - area->vm_start;
    	offset = area->vm_pgoff << PAGE_SHIFT;
    	if (io_remap_pfn_range(area, area->vm_start,
    				(substream->runtime->dma_addr + offset) >> PAGE_SHIFT,
    				size, area->vm_page_prot))
    		return -EAGAIN;
    	return 0;
    }
    
    EXPORT_SYMBOL(snd_pcm_lib_mmap_iomem);
    #endif /* SNDRV_PCM_INFO_MMAP */
    
    /*
     * mmap DMA buffer
     */
    int snd_pcm_mmap_data(struct snd_pcm_substream *substream, struct file *file,
    		      struct vm_area_struct *area)
    {
    	struct snd_pcm_runtime *runtime;
    	long size;
    	unsigned long offset;
    	size_t dma_bytes;
    	int err;
    
    	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
    		if (!(area->vm_flags & (VM_WRITE|VM_READ)))
    			return -EINVAL;
    	} else {
    		if (!(area->vm_flags & VM_READ))
    			return -EINVAL;
    	}
    	runtime = substream->runtime;
    	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
    		return -EBADFD;
    	if (!(runtime->info & SNDRV_PCM_INFO_MMAP))
    		return -ENXIO;
    	if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
    	    runtime->access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
    		return -EINVAL;
    	size = area->vm_end - area->vm_start;
    	offset = area->vm_pgoff << PAGE_SHIFT;
    	dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
    	if ((size_t)size > dma_bytes)
    		return -EINVAL;
    	if (offset > dma_bytes - size)
    		return -EINVAL;
    
    	area->vm_ops = &snd_pcm_vm_ops_data;
    	area->vm_private_data = substream;
    	if (substream->ops->mmap)
    		err = substream->ops->mmap(substream, area);
    	else
    		err = snd_pcm_default_mmap(substream, area);
    	if (!err)
    		atomic_inc(&substream->mmap_count);
    	return err;
    }
    
    EXPORT_SYMBOL(snd_pcm_mmap_data);
    
    static int snd_pcm_mmap(struct file *file, struct vm_area_struct *area)
    {
    	struct snd_pcm_file * pcm_file;
    	struct snd_pcm_substream *substream;	
    	unsigned long offset;
    	
    	pcm_file = file->private_data;
    	substream = pcm_file->substream;
    	if (PCM_RUNTIME_CHECK(substream))
    		return -ENXIO;
    
    	offset = area->vm_pgoff << PAGE_SHIFT;
    	switch (offset) {
    	case SNDRV_PCM_MMAP_OFFSET_STATUS:
    		if (pcm_file->no_compat_mmap)
    			return -ENXIO;
    		return snd_pcm_mmap_status(substream, file, area);
    	case SNDRV_PCM_MMAP_OFFSET_CONTROL:
    		if (pcm_file->no_compat_mmap)
    			return -ENXIO;
    		return snd_pcm_mmap_control(substream, file, area);
    	default:
    		return snd_pcm_mmap_data(substream, file, area);
    	}
    	return 0;
    }
    
    static int snd_pcm_fasync(int fd, struct file * file, int on)
    {
    	struct snd_pcm_file * pcm_file;
    	struct snd_pcm_substream *substream;
    	struct snd_pcm_runtime *runtime;
    
    	pcm_file = file->private_data;
    	substream = pcm_file->substream;
    	if (PCM_RUNTIME_CHECK(substream))
    		return -ENXIO;
    	runtime = substream->runtime;
    	return fasync_helper(fd, file, on, &runtime->fasync);
    }
    
    /*
     * ioctl32 compat
     */
    #ifdef CONFIG_COMPAT
    #include "pcm_compat.c"
    #else
    #define snd_pcm_ioctl_compat	NULL
    #endif
    
    /*
     *  To be removed helpers to keep binary compatibility
     */
    
    #ifdef CONFIG_SND_SUPPORT_OLD_API
    #define __OLD_TO_NEW_MASK(x) ((x&7)|((x&0x07fffff8)<<5))
    #define __NEW_TO_OLD_MASK(x) ((x&7)|((x&0xffffff00)>>5))
    
    static void snd_pcm_hw_convert_from_old_params(struct snd_pcm_hw_params *params,
    					       struct snd_pcm_hw_params_old *oparams)
    {
    	unsigned int i;
    
    	memset(params, 0, sizeof(*params));
    	params->flags = oparams->flags;
    	for (i = 0; i < ARRAY_SIZE(oparams->masks); i++)
    		params->masks[i].bits[0] = oparams->masks[i];
    	memcpy(params->intervals, oparams->intervals, sizeof(oparams->intervals));
    	params->rmask = __OLD_TO_NEW_MASK(oparams->rmask);
    	params->cmask = __OLD_TO_NEW_MASK(oparams->cmask);
    	params->info = oparams->info;
    	params->msbits = oparams->msbits;
    	params->rate_num = oparams->rate_num;
    	params->rate_den = oparams->rate_den;
    	params->fifo_size = oparams->fifo_size;
    }
    
    static void snd_pcm_hw_convert_to_old_params(struct snd_pcm_hw_params_old *oparams,
    					     struct snd_pcm_hw_params *params)
    {
    	unsigned int i;
    
    	memset(oparams, 0, sizeof(*oparams));
    	oparams->flags = params->flags;
    	for (i = 0; i < ARRAY_SIZE(oparams->masks); i++)
    		oparams->masks[i] = params->masks[i].bits[0];
    	memcpy(oparams->intervals, params->intervals, sizeof(oparams->intervals));
    	oparams->rmask = __NEW_TO_OLD_MASK(params->rmask);
    	oparams->cmask = __NEW_TO_OLD_MASK(params->cmask);
    	oparams->info = params->info;
    	oparams->msbits = params->msbits;
    	oparams->rate_num = params->rate_num;
    	oparams->rate_den = params->rate_den;
    	oparams->fifo_size = params->fifo_size;
    }
    
    static int snd_pcm_hw_refine_old_user(struct snd_pcm_substream *substream,
    				      struct snd_pcm_hw_params_old __user * _oparams)
    {
    	struct snd_pcm_hw_params *params;
    	struct snd_pcm_hw_params_old *oparams = NULL;
    	int err;
    
    	params = kmalloc(sizeof(*params), GFP_KERNEL);
    	if (!params)
    		return -ENOMEM;
    
    	oparams = memdup_user(_oparams, sizeof(*oparams));
    	if (IS_ERR(oparams)) {
    		err = PTR_ERR(oparams);
    		goto out;
    	}
    	snd_pcm_hw_convert_from_old_params(params, oparams);
    	err = snd_pcm_hw_refine(substream, params);
    	snd_pcm_hw_convert_to_old_params(oparams, params);
    	if (copy_to_user(_oparams, oparams, sizeof(*oparams))) {
    		if (!err)
    			err = -EFAULT;
    	}
    
    	kfree(oparams);
    out:
    	kfree(params);
    	return err;
    }
    
    static int snd_pcm_hw_params_old_user(struct snd_pcm_substream *substream,
    				      struct snd_pcm_hw_params_old __user * _oparams)
    {
    	struct snd_pcm_hw_params *params;
    	struct snd_pcm_hw_params_old *oparams = NULL;
    	int err;
    
    	params = kmalloc(sizeof(*params), GFP_KERNEL);
    	if (!params)
    		return -ENOMEM;
    
    	oparams = memdup_user(_oparams, sizeof(*oparams));
    	if (IS_ERR(oparams)) {
    		err = PTR_ERR(oparams);
    		goto out;
    	}
    	snd_pcm_hw_convert_from_old_params(params, oparams);
    	err = snd_pcm_hw_params(substream, params);
    	snd_pcm_hw_convert_to_old_params(oparams, params);
    	if (copy_to_user(_oparams, oparams, sizeof(*oparams))) {
    		if (!err)
    			err = -EFAULT;
    	}
    
    	kfree(oparams);
    out:
    	kfree(params);
    	return err;
    }
    #endif /* CONFIG_SND_SUPPORT_OLD_API */
    
    #ifndef CONFIG_MMU
    static unsigned long snd_pcm_get_unmapped_area(struct file *file,
    					       unsigned long addr,
    					       unsigned long len,
    					       unsigned long pgoff,
    					       unsigned long flags)
    {
    	struct snd_pcm_file *pcm_file = file->private_data;
    	struct snd_pcm_substream *substream = pcm_file->substream;
    	struct snd_pcm_runtime *runtime = substream->runtime;
    	unsigned long offset = pgoff << PAGE_SHIFT;
    
    	switch (offset) {
    	case SNDRV_PCM_MMAP_OFFSET_STATUS:
    		return (unsigned long)runtime->status;
    	case SNDRV_PCM_MMAP_OFFSET_CONTROL:
    		return (unsigned long)runtime->control;
    	default:
    		return (unsigned long)runtime->dma_area + offset;
    	}
    }
    #else
    # define snd_pcm_get_unmapped_area NULL
    #endif
    
    /*
     *  Register section
     */
    
    const struct file_operations snd_pcm_f_ops[2] = {
    	{
    		.owner =		THIS_MODULE,
    		.write =		snd_pcm_write,
    		.aio_write =		snd_pcm_aio_write,
    		.open =			snd_pcm_playback_open,
    		.release =		snd_pcm_release,
    		.llseek =		no_llseek,
    		.poll =			snd_pcm_playback_poll,
    		.unlocked_ioctl =	snd_pcm_playback_ioctl,
    		.compat_ioctl = 	snd_pcm_ioctl_compat,
    		.mmap =			snd_pcm_mmap,
    		.fasync =		snd_pcm_fasync,
    		.get_unmapped_area =	snd_pcm_get_unmapped_area,
    	},
    	{
    		.owner =		THIS_MODULE,
    		.read =			snd_pcm_read,
    		.aio_read =		snd_pcm_aio_read,
    		.open =			snd_pcm_capture_open,
    		.release =		snd_pcm_release,
    		.llseek =		no_llseek,
    		.poll =			snd_pcm_capture_poll,
    		.unlocked_ioctl =	snd_pcm_capture_ioctl,
    		.compat_ioctl = 	snd_pcm_ioctl_compat,
    		.mmap =			snd_pcm_mmap,
    		.fasync =		snd_pcm_fasync,
    		.get_unmapped_area =	snd_pcm_get_unmapped_area,
    	}
    };