/*
 *  Digital Audio (PCM) abstract layer / OSS compatible
 *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
 *
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#if 0
#define PLUGIN_DEBUG
#endif
#if 0
#define OSS_DEBUG
#endif

#include <sound/driver.h>
#include <linux/init.h>
#include <linux/smp_lock.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/vmalloc.h>
#include <linux/moduleparam.h>
#include <sound/core.h>
#include <sound/minors.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include "pcm_plugin.h"
#include <sound/info.h>
#include <linux/soundcard.h>
#include <sound/initval.h>

#define OSS_ALSAEMULVER         _SIOR ('M', 249, int)

static int dsp_map[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = 0};
static int adsp_map[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = 1};
static int nonblock_open = 1;

MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>, Abramo Bagnara <abramo@alsa-project.org>");
MODULE_DESCRIPTION("PCM OSS emulation for ALSA.");
MODULE_LICENSE("GPL");
module_param_array(dsp_map, int, NULL, 0444);
MODULE_PARM_DESC(dsp_map, "PCM device number assigned to 1st OSS device.");
module_param_array(adsp_map, int, NULL, 0444);
MODULE_PARM_DESC(adsp_map, "PCM device number assigned to 2nd OSS device.");
module_param(nonblock_open, bool, 0644);
MODULE_PARM_DESC(nonblock_open, "Don't block opening busy PCM devices.");
MODULE_ALIAS_SNDRV_MINOR(SNDRV_MINOR_OSS_PCM);
MODULE_ALIAS_SNDRV_MINOR(SNDRV_MINOR_OSS_PCM1);

extern int snd_mixer_oss_ioctl_card(snd_card_t *card, unsigned int cmd, unsigned long arg);
static int snd_pcm_oss_get_rate(snd_pcm_oss_file_t *pcm_oss_file);
static int snd_pcm_oss_get_channels(snd_pcm_oss_file_t *pcm_oss_file);
static int snd_pcm_oss_get_format(snd_pcm_oss_file_t *pcm_oss_file);

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);
}

static int snd_pcm_oss_plugin_clear(snd_pcm_substream_t *substream)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        snd_pcm_plugin_t *plugin, *next;
        
        plugin = runtime->oss.plugin_first;
        while (plugin) {
                next = plugin->next;
                snd_pcm_plugin_free(plugin);
                plugin = next;
        }
        runtime->oss.plugin_first = runtime->oss.plugin_last = NULL;
        return 0;
}

static int snd_pcm_plugin_insert(snd_pcm_plugin_t *plugin)
{
        snd_pcm_runtime_t *runtime = plugin->plug->runtime;
        plugin->next = runtime->oss.plugin_first;
        plugin->prev = NULL;
        if (runtime->oss.plugin_first) {
                runtime->oss.plugin_first->prev = plugin;
                runtime->oss.plugin_first = plugin;
        } else {
                runtime->oss.plugin_last =
                runtime->oss.plugin_first = plugin;
        }
        return 0;
}

int snd_pcm_plugin_append(snd_pcm_plugin_t *plugin)
{
        snd_pcm_runtime_t *runtime = plugin->plug->runtime;
        plugin->next = NULL;
        plugin->prev = runtime->oss.plugin_last;
        if (runtime->oss.plugin_last) {
                runtime->oss.plugin_last->next = plugin;
                runtime->oss.plugin_last = plugin;
        } else {
                runtime->oss.plugin_last =
                runtime->oss.plugin_first = plugin;
        }
        return 0;
}

static long snd_pcm_oss_bytes(snd_pcm_substream_t *substream, long frames)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        snd_pcm_uframes_t buffer_size = snd_pcm_lib_buffer_bytes(substream);
        frames = frames_to_bytes(runtime, frames);
        if (buffer_size == runtime->oss.buffer_bytes)
                return frames;
        return (runtime->oss.buffer_bytes * frames) / buffer_size;
}

static long snd_pcm_alsa_frames(snd_pcm_substream_t *substream, long bytes)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        snd_pcm_uframes_t buffer_size = snd_pcm_lib_buffer_bytes(substream);
        if (buffer_size == runtime->oss.buffer_bytes)
                return bytes_to_frames(runtime, bytes);
        return bytes_to_frames(runtime, (buffer_size * bytes) / runtime->oss.buffer_bytes);
}

static int snd_pcm_oss_format_from(int format)
{
        switch (format) {
        case AFMT_MU_LAW:       return SNDRV_PCM_FORMAT_MU_LAW;
        case AFMT_A_LAW:        return SNDRV_PCM_FORMAT_A_LAW;
        case AFMT_IMA_ADPCM:    return SNDRV_PCM_FORMAT_IMA_ADPCM;
        case AFMT_U8:           return SNDRV_PCM_FORMAT_U8;
        case AFMT_S16_LE:       return SNDRV_PCM_FORMAT_S16_LE;
        case AFMT_S16_BE:       return SNDRV_PCM_FORMAT_S16_BE;
        case AFMT_S8:           return SNDRV_PCM_FORMAT_S8;
        case AFMT_U16_LE:       return SNDRV_PCM_FORMAT_U16_LE;
        case AFMT_U16_BE:       return SNDRV_PCM_FORMAT_U16_BE;
        case AFMT_MPEG:         return SNDRV_PCM_FORMAT_MPEG;
        default:                return SNDRV_PCM_FORMAT_U8;
        }
}

static int snd_pcm_oss_format_to(int format)
{
        switch (format) {
        case SNDRV_PCM_FORMAT_MU_LAW:   return AFMT_MU_LAW;
        case SNDRV_PCM_FORMAT_A_LAW:    return AFMT_A_LAW;
        case SNDRV_PCM_FORMAT_IMA_ADPCM:        return AFMT_IMA_ADPCM;
        case SNDRV_PCM_FORMAT_U8:               return AFMT_U8;
        case SNDRV_PCM_FORMAT_S16_LE:   return AFMT_S16_LE;
        case SNDRV_PCM_FORMAT_S16_BE:   return AFMT_S16_BE;
        case SNDRV_PCM_FORMAT_S8:               return AFMT_S8;
        case SNDRV_PCM_FORMAT_U16_LE:   return AFMT_U16_LE;
        case SNDRV_PCM_FORMAT_U16_BE:   return AFMT_U16_BE;
        case SNDRV_PCM_FORMAT_MPEG:             return AFMT_MPEG;
        default:                        return -EINVAL;
        }
}

static int snd_pcm_oss_period_size(snd_pcm_substream_t *substream, 
                                   snd_pcm_hw_params_t *oss_params,
                                   snd_pcm_hw_params_t *slave_params)
{
        size_t s;
        size_t oss_buffer_size, oss_period_size, oss_periods;
        size_t min_period_size, max_period_size;
        snd_pcm_runtime_t *runtime = substream->runtime;
        size_t oss_frame_size;

        oss_frame_size = snd_pcm_format_physical_width(params_format(oss_params)) *
                         params_channels(oss_params) / 8;

        oss_buffer_size = snd_pcm_plug_client_size(substream,
                                                   snd_pcm_hw_param_value_max(slave_params, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, NULL)) * oss_frame_size;
        oss_buffer_size = 1 << ld2(oss_buffer_size);
        if (atomic_read(&runtime->mmap_count)) {
                if (oss_buffer_size > runtime->oss.mmap_bytes)
                        oss_buffer_size = runtime->oss.mmap_bytes;
        }

        if (substream->oss.setup &&
            substream->oss.setup->period_size > 16)
                oss_period_size = substream->oss.setup->period_size;
        else if (runtime->oss.fragshift) {
                oss_period_size = 1 << runtime->oss.fragshift;
                if (oss_period_size > oss_buffer_size / 2)
                        oss_period_size = oss_buffer_size / 2;
        } else {
                int sd;
                size_t bytes_per_sec = params_rate(oss_params) * snd_pcm_format_physical_width(params_format(oss_params)) * params_channels(oss_params) / 8;

                oss_period_size = oss_buffer_size;
                do {
                        oss_period_size /= 2;
                } while (oss_period_size > bytes_per_sec);
                if (runtime->oss.subdivision == 0) {
                        sd = 4;
                        if (oss_period_size / sd > 4096)
                                sd *= 2;
                        if (oss_period_size / sd < 4096)
                                sd = 1;
                } else
                        sd = runtime->oss.subdivision;
                oss_period_size /= sd;
                if (oss_period_size < 16)
                        oss_period_size = 16;
        }

        min_period_size = snd_pcm_plug_client_size(substream,
                                                   snd_pcm_hw_param_value_min(slave_params, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, NULL));
        min_period_size *= oss_frame_size;
        min_period_size = 1 << (ld2(min_period_size - 1) + 1);
        if (oss_period_size < min_period_size)
                oss_period_size = min_period_size;

        max_period_size = snd_pcm_plug_client_size(substream,
                                                   snd_pcm_hw_param_value_max(slave_params, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, NULL));
        max_period_size *= oss_frame_size;
        max_period_size = 1 << ld2(max_period_size);
        if (oss_period_size > max_period_size)
                oss_period_size = max_period_size;

        oss_periods = oss_buffer_size / oss_period_size;

        if (substream->oss.setup) {
                if (substream->oss.setup->periods > 1)
                        oss_periods = substream->oss.setup->periods;
        }

        s = snd_pcm_hw_param_value_max(slave_params, SNDRV_PCM_HW_PARAM_PERIODS, NULL);
        if (runtime->oss.maxfrags && s > runtime->oss.maxfrags)
                s = runtime->oss.maxfrags;
        if (oss_periods > s)
                oss_periods = s;

        s = snd_pcm_hw_param_value_min(slave_params, SNDRV_PCM_HW_PARAM_PERIODS, NULL);
        if (s < 2)
                s = 2;
        if (oss_periods < s)
                oss_periods = s;

        while (oss_period_size * oss_periods > oss_buffer_size)
                oss_period_size /= 2;

        snd_assert(oss_period_size >= 16, return -EINVAL);
        runtime->oss.period_bytes = oss_period_size;
        runtime->oss.period_frames = 1;
        runtime->oss.periods = oss_periods;
        return 0;
}

static int choose_rate(snd_pcm_substream_t *substream,
                       snd_pcm_hw_params_t *params, unsigned int best_rate)
{
        snd_interval_t *it;
        snd_pcm_hw_params_t *save;
        unsigned int rate, prev;

        save = kmalloc(sizeof(*save), GFP_KERNEL);
        if (save == NULL)
                return -ENOMEM;
        *save = *params;
        it = hw_param_interval(save, SNDRV_PCM_HW_PARAM_RATE);

        /* try multiples of the best rate */
        rate = best_rate;
        for (;;) {
                if (it->max < rate || (it->max == rate && it->openmax))
                        break;
                if (it->min < rate || (it->min == rate && !it->openmin)) {
                        int ret;
                        ret = snd_pcm_hw_param_set(substream, params,
                                                   SNDRV_PCM_HW_PARAM_RATE,
                                                   rate, 0);
                        if (ret == (int)rate) {
                                kfree(save);
                                return rate;
                        }
                        *params = *save;
                }
                prev = rate;
                rate += best_rate;
                if (rate <= prev)
                        break;
        }

        /* not found, use the nearest rate */
        kfree(save);
        return snd_pcm_hw_param_near(substream, params, SNDRV_PCM_HW_PARAM_RATE, best_rate, NULL);
}

static int snd_pcm_oss_change_params(snd_pcm_substream_t *substream)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        snd_pcm_hw_params_t *params, *sparams;
        snd_pcm_sw_params_t *sw_params;
        ssize_t oss_buffer_size, oss_period_size;
        size_t oss_frame_size;
        int err;
        int direct;
        int format, sformat, n;
        snd_mask_t sformat_mask;
        snd_mask_t mask;

        sw_params = kmalloc(sizeof(*sw_params), GFP_KERNEL);
        params = kmalloc(sizeof(*params), GFP_KERNEL);
        sparams = kmalloc(sizeof(*sparams), GFP_KERNEL);
        if (!sw_params || !params || !sparams) {
                snd_printd("No memory\n");
                err = -ENOMEM;
                goto failure;
        }

        if (atomic_read(&runtime->mmap_count)) {
                direct = 1;
        } else {
                snd_pcm_oss_setup_t *setup = substream->oss.setup;
                direct = (setup != NULL && setup->direct);
        }

        _snd_pcm_hw_params_any(sparams);
        _snd_pcm_hw_param_setinteger(sparams, SNDRV_PCM_HW_PARAM_PERIODS);
        _snd_pcm_hw_param_min(sparams, SNDRV_PCM_HW_PARAM_PERIODS, 2, 0);
        snd_mask_none(&mask);
        if (atomic_read(&runtime->mmap_count))
                snd_mask_set(&mask, SNDRV_PCM_ACCESS_MMAP_INTERLEAVED);
        else {
                snd_mask_set(&mask, SNDRV_PCM_ACCESS_RW_INTERLEAVED);
                if (!direct)
                        snd_mask_set(&mask, SNDRV_PCM_ACCESS_RW_NONINTERLEAVED);
        }
        err = snd_pcm_hw_param_mask(substream, sparams, SNDRV_PCM_HW_PARAM_ACCESS, &mask);
        if (err < 0) {
                snd_printd("No usable accesses\n");
                err = -EINVAL;
                goto failure;
        }
        choose_rate(substream, sparams, runtime->oss.rate);
        snd_pcm_hw_param_near(substream, sparams, SNDRV_PCM_HW_PARAM_CHANNELS, runtime->oss.channels, NULL);

        format = snd_pcm_oss_format_from(runtime->oss.format);

        sformat_mask = *hw_param_mask(sparams, SNDRV_PCM_HW_PARAM_FORMAT);
        if (direct)
                sformat = format;
        else
                sformat = snd_pcm_plug_slave_format(format, &sformat_mask);

        if (sformat < 0 || !snd_mask_test(&sformat_mask, sformat)) {
                for (sformat = 0; sformat <= SNDRV_PCM_FORMAT_LAST; sformat++) {
                        if (snd_mask_test(&sformat_mask, sformat) &&
                            snd_pcm_oss_format_to(sformat) >= 0)
                                break;
                }
                if (sformat > SNDRV_PCM_FORMAT_LAST) {
                        snd_printd("Cannot find a format!!!\n");
                        err = -EINVAL;
                        goto failure;
                }
        }
        err = _snd_pcm_hw_param_set(sparams, SNDRV_PCM_HW_PARAM_FORMAT, sformat, 0);
        snd_assert(err >= 0, goto failure);

        if (direct) {
                memcpy(params, sparams, sizeof(*params));
        } else {
                _snd_pcm_hw_params_any(params);
                _snd_pcm_hw_param_set(params, SNDRV_PCM_HW_PARAM_ACCESS,
                                      SNDRV_PCM_ACCESS_RW_INTERLEAVED, 0);
                _snd_pcm_hw_param_set(params, SNDRV_PCM_HW_PARAM_FORMAT,
                                      snd_pcm_oss_format_from(runtime->oss.format), 0);
                _snd_pcm_hw_param_set(params, SNDRV_PCM_HW_PARAM_CHANNELS,
                                      runtime->oss.channels, 0);
                _snd_pcm_hw_param_set(params, SNDRV_PCM_HW_PARAM_RATE,
                                      runtime->oss.rate, 0);
                pdprintf("client: access = %i, format = %i, channels = %i, rate = %i\n",
                         params_access(params), params_format(params),
                         params_channels(params), params_rate(params));
        }
        pdprintf("slave: access = %i, format = %i, channels = %i, rate = %i\n",
                 params_access(sparams), params_format(sparams),
                 params_channels(sparams), params_rate(sparams));

        oss_frame_size = snd_pcm_format_physical_width(params_format(params)) *
                         params_channels(params) / 8;

        snd_pcm_oss_plugin_clear(substream);
        if (!direct) {
                /* add necessary plugins */
                snd_pcm_oss_plugin_clear(substream);
                if ((err = snd_pcm_plug_format_plugins(substream,
                                                       params, 
                                                       sparams)) < 0) {
                        snd_printd("snd_pcm_plug_format_plugins failed: %i\n", err);
                        snd_pcm_oss_plugin_clear(substream);
                        goto failure;
                }
                if (runtime->oss.plugin_first) {
                        snd_pcm_plugin_t *plugin;
                        if ((err = snd_pcm_plugin_build_io(substream, sparams, &plugin)) < 0) {
                                snd_printd("snd_pcm_plugin_build_io failed: %i\n", err);
                                snd_pcm_oss_plugin_clear(substream);
                                goto failure;
                        }
                        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
                                err = snd_pcm_plugin_append(plugin);
                        } else {
                                err = snd_pcm_plugin_insert(plugin);
                        }
                        if (err < 0) {
                                snd_pcm_oss_plugin_clear(substream);
                                goto failure;
                        }
                }
        }

        err = snd_pcm_oss_period_size(substream, params, sparams);
        if (err < 0)
                goto failure;

        n = snd_pcm_plug_slave_size(substream, runtime->oss.period_bytes / oss_frame_size);
        err = snd_pcm_hw_param_near(substream, sparams, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, n, NULL);
        snd_assert(err >= 0, goto failure);

        err = snd_pcm_hw_param_near(substream, sparams, SNDRV_PCM_HW_PARAM_PERIODS,
                                     runtime->oss.periods, NULL);
        snd_assert(err >= 0, goto failure);

        snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_DROP, NULL);

        if ((err = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_HW_PARAMS, sparams)) < 0) {
                snd_printd("HW_PARAMS failed: %i\n", err);
                goto failure;
        }

        memset(sw_params, 0, sizeof(*sw_params));
        if (runtime->oss.trigger) {
                sw_params->start_threshold = 1;
        } else {
                sw_params->start_threshold = runtime->boundary;
        }
        if (atomic_read(&runtime->mmap_count) || substream->stream == SNDRV_PCM_STREAM_CAPTURE)
                sw_params->stop_threshold = runtime->boundary;
        else
                sw_params->stop_threshold = runtime->buffer_size;
        sw_params->tstamp_mode = SNDRV_PCM_TSTAMP_NONE;
        sw_params->period_step = 1;
        sw_params->sleep_min = 0;
        sw_params->avail_min = 1;
        sw_params->xfer_align = 1;
        if (atomic_read(&runtime->mmap_count) ||
            (substream->oss.setup && substream->oss.setup->nosilence)) {
                sw_params->silence_threshold = 0;
                sw_params->silence_size = 0;
        } else {
                snd_pcm_uframes_t frames;
                frames = runtime->period_size + 16;
                if (frames > runtime->buffer_size)
                        frames = runtime->buffer_size;
                sw_params->silence_threshold = frames;
                sw_params->silence_size = frames;
        }

        if ((err = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_SW_PARAMS, sw_params)) < 0) {
                snd_printd("SW_PARAMS failed: %i\n", err);
                goto failure;
        }

        runtime->oss.periods = params_periods(sparams);
        oss_period_size = snd_pcm_plug_client_size(substream, params_period_size(sparams));
        snd_assert(oss_period_size >= 0, err = -EINVAL; goto failure);
        if (runtime->oss.plugin_first) {
                err = snd_pcm_plug_alloc(substream, oss_period_size);
                if (err < 0)
                        goto failure;
        }
        oss_period_size *= oss_frame_size;

        oss_buffer_size = oss_period_size * runtime->oss.periods;
        snd_assert(oss_buffer_size >= 0, err = -EINVAL; goto failure);

        runtime->oss.period_bytes = oss_period_size;
        runtime->oss.buffer_bytes = oss_buffer_size;

        pdprintf("oss: period bytes = %i, buffer bytes = %i\n",
                 runtime->oss.period_bytes,
                 runtime->oss.buffer_bytes);
        pdprintf("slave: period_size = %i, buffer_size = %i\n",
                 params_period_size(sparams),
                 params_buffer_size(sparams));

        runtime->oss.format = snd_pcm_oss_format_to(params_format(params));
        runtime->oss.channels = params_channels(params);
        runtime->oss.rate = params_rate(params);

        runtime->oss.params = 0;
        runtime->oss.prepare = 1;
        vfree(runtime->oss.buffer);
        runtime->oss.buffer = vmalloc(runtime->oss.period_bytes);
        runtime->oss.buffer_used = 0;
        if (runtime->dma_area)
                snd_pcm_format_set_silence(runtime->format, runtime->dma_area, bytes_to_samples(runtime, runtime->dma_bytes));

        runtime->oss.period_frames = snd_pcm_alsa_frames(substream, oss_period_size);

        err = 0;
failure:
        kfree(sw_params);
        kfree(params);
        kfree(sparams);
        return err;
}

static int snd_pcm_oss_get_active_substream(snd_pcm_oss_file_t *pcm_oss_file, snd_pcm_substream_t **r_substream)
{
        int idx, err;
        snd_pcm_substream_t *asubstream = NULL, *substream;

        for (idx = 0; idx < 2; idx++) {
                substream = pcm_oss_file->streams[idx];
                if (substream == NULL)
                        continue;
                if (asubstream == NULL)
                        asubstream = substream;
                if (substream->runtime->oss.params) {
                        err = snd_pcm_oss_change_params(substream);
                        if (err < 0)
                                return err;
                }
        }
        snd_assert(asubstream != NULL, return -EIO);
        if (r_substream)
                *r_substream = asubstream;
        return 0;
}

static int snd_pcm_oss_prepare(snd_pcm_substream_t *substream)
{
        int err;
        snd_pcm_runtime_t *runtime = substream->runtime;

        err = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_PREPARE, NULL);
        if (err < 0) {
                snd_printd("snd_pcm_oss_prepare: SNDRV_PCM_IOCTL_PREPARE failed\n");
                return err;
        }
        runtime->oss.prepare = 0;
        runtime->oss.prev_hw_ptr_interrupt = 0;
        runtime->oss.period_ptr = 0;
        runtime->oss.buffer_used = 0;

        return 0;
}

static int snd_pcm_oss_make_ready(snd_pcm_substream_t *substream)
{
        snd_pcm_runtime_t *runtime;
        int err;

        if (substream == NULL)
                return 0;
        runtime = substream->runtime;
        if (runtime->oss.params) {
                err = snd_pcm_oss_change_params(substream);
                if (err < 0)
                        return err;
        }
        if (runtime->oss.prepare) {
                err = snd_pcm_oss_prepare(substream);
                if (err < 0)
                        return err;
        }
        return 0;
}

static int snd_pcm_oss_capture_position_fixup(snd_pcm_substream_t *substream, snd_pcm_sframes_t *delay)
{
        snd_pcm_runtime_t *runtime;
        snd_pcm_uframes_t frames;
        int err = 0;

        while (1) {
                err = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_DELAY, delay);
                if (err < 0)
                        break;
                runtime = substream->runtime;
                if (*delay <= (snd_pcm_sframes_t)runtime->buffer_size)
                        break;
                /* in case of overrun, skip whole periods like OSS/Linux driver does */
                /* until avail(delay) <= buffer_size */
                frames = (*delay - runtime->buffer_size) + runtime->period_size - 1;
                frames /= runtime->period_size;
                frames *= runtime->period_size;
                err = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_FORWARD, &frames);
                if (err < 0)
                        break;
        }
        return err;
}

snd_pcm_sframes_t snd_pcm_oss_write3(snd_pcm_substream_t *substream, const char *ptr, snd_pcm_uframes_t frames, int in_kernel)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        int ret;
        while (1) {
                if (runtime->status->state == SNDRV_PCM_STATE_XRUN ||
                    runtime->status->state == SNDRV_PCM_STATE_SUSPENDED) {
#ifdef OSS_DEBUG
                        if (runtime->status->state == SNDRV_PCM_STATE_XRUN)
                                printk("pcm_oss: write: recovering from XRUN\n");
                        else
                                printk("pcm_oss: write: recovering from SUSPEND\n");
#endif
                        ret = snd_pcm_oss_prepare(substream);
                        if (ret < 0)
                                break;
                }
                if (in_kernel) {
                        mm_segment_t fs;
                        fs = snd_enter_user();
                        ret = snd_pcm_lib_write(substream, ptr, frames);
                        snd_leave_user(fs);
                } else {
                        ret = snd_pcm_lib_write(substream, ptr, frames);
                }
                if (ret != -EPIPE && ret != -ESTRPIPE)
                        break;
                /* test, if we can't store new data, because the stream */
                /* has not been started */
                if (runtime->status->state == SNDRV_PCM_STATE_PREPARED)
                        return -EAGAIN;
        }
        return ret;
}

snd_pcm_sframes_t snd_pcm_oss_read3(snd_pcm_substream_t *substream, char *ptr, snd_pcm_uframes_t frames, int in_kernel)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        snd_pcm_sframes_t delay;
        int ret;
        while (1) {
                if (runtime->status->state == SNDRV_PCM_STATE_XRUN ||
                    runtime->status->state == SNDRV_PCM_STATE_SUSPENDED) {
#ifdef OSS_DEBUG
                        if (runtime->status->state == SNDRV_PCM_STATE_XRUN)
                                printk("pcm_oss: read: recovering from XRUN\n");
                        else
                                printk("pcm_oss: read: recovering from SUSPEND\n");
#endif
                        ret = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_DRAIN, NULL);
                        if (ret < 0)
                                break;
                } else if (runtime->status->state == SNDRV_PCM_STATE_SETUP) {
                        ret = snd_pcm_oss_prepare(substream);
                        if (ret < 0)
                                break;
                }
                ret = snd_pcm_oss_capture_position_fixup(substream, &delay);
                if (ret < 0)
                        break;
                if (in_kernel) {
                        mm_segment_t fs;
                        fs = snd_enter_user();
                        ret = snd_pcm_lib_read(substream, ptr, frames);
                        snd_leave_user(fs);
                } else {
                        ret = snd_pcm_lib_read(substream, ptr, frames);
                }
                if (ret == -EPIPE) {
                        if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
                                ret = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_DROP, NULL);
                                if (ret < 0)
                                        break;
                        }
                        continue;
                }
                if (ret != -ESTRPIPE)
                        break;
        }
        return ret;
}

snd_pcm_sframes_t snd_pcm_oss_writev3(snd_pcm_substream_t *substream, void **bufs, snd_pcm_uframes_t frames, int in_kernel)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        int ret;
        while (1) {
                if (runtime->status->state == SNDRV_PCM_STATE_XRUN ||
                    runtime->status->state == SNDRV_PCM_STATE_SUSPENDED) {
#ifdef OSS_DEBUG
                        if (runtime->status->state == SNDRV_PCM_STATE_XRUN)
                                printk("pcm_oss: writev: recovering from XRUN\n");
                        else
                                printk("pcm_oss: writev: recovering from SUSPEND\n");
#endif
                        ret = snd_pcm_oss_prepare(substream);
                        if (ret < 0)
                                break;
                }
                if (in_kernel) {
                        mm_segment_t fs;
                        fs = snd_enter_user();
                        ret = snd_pcm_lib_writev(substream, bufs, frames);
                        snd_leave_user(fs);
                } else {
                        ret = snd_pcm_lib_writev(substream, bufs, frames);
                }
                if (ret != -EPIPE && ret != -ESTRPIPE)
                        break;

                /* test, if we can't store new data, because the stream */
                /* has not been started */
                if (runtime->status->state == SNDRV_PCM_STATE_PREPARED)
                        return -EAGAIN;
        }
        return ret;
}
        
snd_pcm_sframes_t snd_pcm_oss_readv3(snd_pcm_substream_t *substream, void **bufs, snd_pcm_uframes_t frames, int in_kernel)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        int ret;
        while (1) {
                if (runtime->status->state == SNDRV_PCM_STATE_XRUN ||
                    runtime->status->state == SNDRV_PCM_STATE_SUSPENDED) {
#ifdef OSS_DEBUG
                        if (runtime->status->state == SNDRV_PCM_STATE_XRUN)
                                printk("pcm_oss: readv: recovering from XRUN\n");
                        else
                                printk("pcm_oss: readv: recovering from SUSPEND\n");
#endif
                        ret = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_DRAIN, NULL);
                        if (ret < 0)
                                break;
                } else if (runtime->status->state == SNDRV_PCM_STATE_SETUP) {
                        ret = snd_pcm_oss_prepare(substream);
                        if (ret < 0)
                                break;
                }
                if (in_kernel) {
                        mm_segment_t fs;
                        fs = snd_enter_user();
                        ret = snd_pcm_lib_readv(substream, bufs, frames);
                        snd_leave_user(fs);
                } else {
                        ret = snd_pcm_lib_readv(substream, bufs, frames);
                }
                if (ret != -EPIPE && ret != -ESTRPIPE)
                        break;
        }
        return ret;
}

static ssize_t snd_pcm_oss_write2(snd_pcm_substream_t *substream, const char *buf, size_t bytes, int in_kernel)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        snd_pcm_sframes_t frames, frames1;
        if (runtime->oss.plugin_first) {
                snd_pcm_plugin_channel_t *channels;
                size_t oss_frame_bytes = (runtime->oss.plugin_first->src_width * runtime->oss.plugin_first->src_format.channels) / 8;
                if (!in_kernel) {
                        if (copy_from_user(runtime->oss.buffer, buf, bytes))
                                return -EFAULT;
                        buf = runtime->oss.buffer;
                }
                frames = bytes / oss_frame_bytes;
                frames1 = snd_pcm_plug_client_channels_buf(substream, (char *)buf, frames, &channels);
                if (frames1 < 0)
                        return frames1;
                frames1 = snd_pcm_plug_write_transfer(substream, channels, frames1);
                if (frames1 <= 0)
                        return frames1;
                bytes = frames1 * oss_frame_bytes;
        } else {
                frames = bytes_to_frames(runtime, bytes);
                frames1 = snd_pcm_oss_write3(substream, buf, frames, in_kernel);
                if (frames1 <= 0)
                        return frames1;
                bytes = frames_to_bytes(runtime, frames1);
        }
        return bytes;
}

static ssize_t snd_pcm_oss_write1(snd_pcm_substream_t *substream, const char __user *buf, size_t bytes)
{
        size_t xfer = 0;
        ssize_t tmp;
        snd_pcm_runtime_t *runtime = substream->runtime;

        if (atomic_read(&runtime->mmap_count))
                return -ENXIO;

        if ((tmp = snd_pcm_oss_make_ready(substream)) < 0)
                return tmp;
        while (bytes > 0) {
                if (bytes < runtime->oss.period_bytes || runtime->oss.buffer_used > 0) {
                        tmp = bytes;
                        if (tmp + runtime->oss.buffer_used > runtime->oss.period_bytes)
                                tmp = runtime->oss.period_bytes - runtime->oss.buffer_used;
                        if (tmp > 0) {
                                if (copy_from_user(runtime->oss.buffer + runtime->oss.buffer_used, buf, tmp))
                                        return xfer > 0 ? (snd_pcm_sframes_t)xfer : -EFAULT;
                        }
                        runtime->oss.buffer_used += tmp;
                        buf += tmp;
                        bytes -= tmp;
                        xfer += tmp;
                        if ((substream->oss.setup != NULL && substream->oss.setup->partialfrag) ||
                            runtime->oss.buffer_used == runtime->oss.period_bytes) {
                                tmp = snd_pcm_oss_write2(substream, runtime->oss.buffer + runtime->oss.period_ptr, 
                                                         runtime->oss.buffer_used - runtime->oss.period_ptr, 1);
                                if (tmp <= 0)
                                        return xfer > 0 ? (snd_pcm_sframes_t)xfer : tmp;
                                runtime->oss.bytes += tmp;
                                runtime->oss.period_ptr += tmp;
                                runtime->oss.period_ptr %= runtime->oss.period_bytes;
                                if (runtime->oss.period_ptr == 0 ||
                                    runtime->oss.period_ptr == runtime->oss.buffer_used)
                                        runtime->oss.buffer_used = 0;
                                else if ((substream->ffile->f_flags & O_NONBLOCK) != 0)
                                        return xfer > 0 ? xfer : -EAGAIN;
                        }
                } else {
                        tmp = snd_pcm_oss_write2(substream, (char *)buf, runtime->oss.period_bytes, 0);
                        if (tmp <= 0)
                                return xfer > 0 ? (snd_pcm_sframes_t)xfer : tmp;
                        runtime->oss.bytes += tmp;
                        buf += tmp;
                        bytes -= tmp;
                        xfer += tmp;
                        if ((substream->ffile->f_flags & O_NONBLOCK) != 0 &&
                            tmp != runtime->oss.period_bytes)
                                break;
                }
        }
        return xfer;
}

static ssize_t snd_pcm_oss_read2(snd_pcm_substream_t *substream, char *buf, size_t bytes, int in_kernel)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        snd_pcm_sframes_t frames, frames1;
        char *final_dst = buf;
        if (runtime->oss.plugin_first) {
                snd_pcm_plugin_channel_t *channels;
                size_t oss_frame_bytes = (runtime->oss.plugin_last->dst_width * runtime->oss.plugin_last->dst_format.channels) / 8;
                if (!in_kernel)
                        buf = runtime->oss.buffer;
                frames = bytes / oss_frame_bytes;
                frames1 = snd_pcm_plug_client_channels_buf(substream, buf, frames, &channels);
                if (frames1 < 0)
                        return frames1;
                frames1 = snd_pcm_plug_read_transfer(substream, channels, frames1);
                if (frames1 <= 0)
                        return frames1;
                bytes = frames1 * oss_frame_bytes;
                if (!in_kernel && copy_to_user(final_dst, buf, bytes))
                        return -EFAULT;
        } else {
                frames = bytes_to_frames(runtime, bytes);
                frames1 = snd_pcm_oss_read3(substream, buf, frames, in_kernel);
                if (frames1 <= 0)
                        return frames1;
                bytes = frames_to_bytes(runtime, frames1);
        }
        return bytes;
}

static ssize_t snd_pcm_oss_read1(snd_pcm_substream_t *substream, char __user *buf, size_t bytes)
{
        size_t xfer = 0;
        ssize_t tmp;
        snd_pcm_runtime_t *runtime = substream->runtime;

        if (atomic_read(&runtime->mmap_count))
                return -ENXIO;

        if ((tmp = snd_pcm_oss_make_ready(substream)) < 0)
                return tmp;
        while (bytes > 0) {
                if (bytes < runtime->oss.period_bytes || runtime->oss.buffer_used > 0) {
                        if (runtime->oss.buffer_used == 0) {
                                tmp = snd_pcm_oss_read2(substream, runtime->oss.buffer, runtime->oss.period_bytes, 1);
                                if (tmp <= 0)
                                        return xfer > 0 ? (snd_pcm_sframes_t)xfer : tmp;
                                runtime->oss.bytes += tmp;
                                runtime->oss.period_ptr = tmp;
                                runtime->oss.buffer_used = tmp;
                        }
                        tmp = bytes;
                        if ((size_t) tmp > runtime->oss.buffer_used)
                                tmp = runtime->oss.buffer_used;
                        if (copy_to_user(buf, runtime->oss.buffer + (runtime->oss.period_ptr - runtime->oss.buffer_used), tmp))
                                return xfer > 0 ? (snd_pcm_sframes_t)xfer : -EFAULT;
                        buf += tmp;
                        bytes -= tmp;
                        xfer += tmp;
                        runtime->oss.buffer_used -= tmp;
                } else {
                        tmp = snd_pcm_oss_read2(substream, (char *)buf, runtime->oss.period_bytes, 0);
                        if (tmp <= 0)
                                return xfer > 0 ? (snd_pcm_sframes_t)xfer : tmp;
                        runtime->oss.bytes += tmp;
                        buf += tmp;
                        bytes -= tmp;
                        xfer += tmp;
                }
        }
        return xfer;
}

static int snd_pcm_oss_reset(snd_pcm_oss_file_t *pcm_oss_file)
{
        snd_pcm_substream_t *substream;

        substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
        if (substream != NULL) {
                snd_pcm_kernel_playback_ioctl(substream, SNDRV_PCM_IOCTL_DROP, NULL);
                substream->runtime->oss.prepare = 1;
        }
        substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_CAPTURE];
        if (substream != NULL) {
                snd_pcm_kernel_capture_ioctl(substream, SNDRV_PCM_IOCTL_DROP, NULL);
                substream->runtime->oss.prepare = 1;
        }
        return 0;
}

static int snd_pcm_oss_post(snd_pcm_oss_file_t *pcm_oss_file)
{
        snd_pcm_substream_t *substream;
        int err;

        substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
        if (substream != NULL) {
                if ((err = snd_pcm_oss_make_ready(substream)) < 0)
                        return err;
                snd_pcm_kernel_playback_ioctl(substream, SNDRV_PCM_IOCTL_START, NULL);
        }
        /* note: all errors from the start action are ignored */
        /* OSS apps do not know, how to handle them */
        return 0;
}

static int snd_pcm_oss_sync1(snd_pcm_substream_t *substream, size_t size)
{
        snd_pcm_runtime_t *runtime;
        ssize_t result = 0;
        long res;
        wait_queue_t wait;

        runtime = substream->runtime;
        init_waitqueue_entry(&wait, current);
        add_wait_queue(&runtime->sleep, &wait);
#ifdef OSS_DEBUG
        printk("sync1: size = %li\n", size);
#endif
        while (1) {
                result = snd_pcm_oss_write2(substream, runtime->oss.buffer, size, 1);
                if (result > 0) {
                        runtime->oss.buffer_used = 0;
                        result = 0;
                        break;
                }
                if (result != 0 && result != -EAGAIN)
                        break;
                result = 0;
                set_current_state(TASK_INTERRUPTIBLE);
                snd_pcm_stream_lock_irq(substream);
                res = runtime->status->state;
                snd_pcm_stream_unlock_irq(substream);
                if (res != SNDRV_PCM_STATE_RUNNING) {
                        set_current_state(TASK_RUNNING);
                        break;
                }
                res = schedule_timeout(10 * HZ);
                if (signal_pending(current)) {
                        result = -ERESTARTSYS;
                        break;
                }
                if (res == 0) {
                        snd_printk(KERN_ERR "OSS sync error - DMA timeout\n");

                        result = -EIO;
                        break;
                }
        }
        remove_wait_queue(&runtime->sleep, &wait);
        return result;
}

static int snd_pcm_oss_sync(snd_pcm_oss_file_t *pcm_oss_file)
{
        int err = 0;
        unsigned int saved_f_flags;
        snd_pcm_substream_t *substream;
        snd_pcm_runtime_t *runtime;
        snd_pcm_format_t format;
        unsigned long width;
        size_t size;

        substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
        if (substream != NULL) {
                runtime = substream->runtime;
                if (atomic_read(&runtime->mmap_count))
                        goto __direct;
                if ((err = snd_pcm_oss_make_ready(substream)) < 0)
                        return err;
                format = snd_pcm_oss_format_from(runtime->oss.format);
                width = snd_pcm_format_physical_width(format);
                if (runtime->oss.buffer_used > 0) {
#ifdef OSS_DEBUG
                        printk("sync: buffer_used\n");
#endif
                        size = (8 * (runtime->oss.period_bytes - runtime->oss.buffer_used) + 7) / width;
                        snd_pcm_format_set_silence(format,
                                                   runtime->oss.buffer + runtime->oss.buffer_used,
                                                   size);
                        err = snd_pcm_oss_sync1(substream, runtime->oss.period_bytes);
                        if (err < 0)
                                return err;
                } else if (runtime->oss.period_ptr > 0) {
#ifdef OSS_DEBUG
                        printk("sync: period_ptr\n");
#endif
                        size = runtime->oss.period_bytes - runtime->oss.period_ptr;
                        snd_pcm_format_set_silence(format,
                                                   runtime->oss.buffer,
                                                   size * 8 / width);
                        err = snd_pcm_oss_sync1(substream, size);
                        if (err < 0)
                                return err;
                }
                /*
                 * The ALSA's period might be a bit large than OSS one.
                 * Fill the remain portion of ALSA period with zeros.
                 */
                size = runtime->control->appl_ptr % runtime->period_size;
                if (size > 0) {
                        size = runtime->period_size - size;
                        if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED) {
                                size = (runtime->frame_bits * size) / 8;
                                while (size > 0) {
                                        size_t size1 = size < runtime->oss.period_bytes ? size : runtime->oss.period_bytes;
                                        size -= size1;
                                        size1 *= 8;
                                        size1 /= runtime->sample_bits;
                                        snd_pcm_format_set_silence(runtime->format,
                                                                   runtime->oss.buffer,
                                                                   size1);
                                        snd_pcm_lib_write(substream, runtime->oss.buffer, size1);
                                }
                        } else if (runtime->access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED) {
                                void __user *buffers[runtime->channels];
                                memset(buffers, 0, runtime->channels * sizeof(void *));
                                snd_pcm_lib_writev(substream, buffers, size);
                        }
                }
                /*
                 * finish sync: drain the buffer
                 */
              __direct:
                saved_f_flags = substream->ffile->f_flags;
                substream->ffile->f_flags &= ~O_NONBLOCK;
                err = snd_pcm_kernel_playback_ioctl(substream, SNDRV_PCM_IOCTL_DRAIN, NULL);
                substream->ffile->f_flags = saved_f_flags;
                if (err < 0)
                        return err;
                runtime->oss.prepare = 1;
        }

        substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_CAPTURE];
        if (substream != NULL) {
                if ((err = snd_pcm_oss_make_ready(substream)) < 0)
                        return err;
                runtime = substream->runtime;
                err = snd_pcm_kernel_capture_ioctl(substream, SNDRV_PCM_IOCTL_DROP, NULL);
                if (err < 0)
                        return err;
                runtime->oss.buffer_used = 0;
                runtime->oss.prepare = 1;
        }
        return 0;
}

static int snd_pcm_oss_set_rate(snd_pcm_oss_file_t *pcm_oss_file, int rate)
{
        int idx;

        for (idx = 1; idx >= 0; --idx) {
                snd_pcm_substream_t *substream = pcm_oss_file->streams[idx];
                snd_pcm_runtime_t *runtime;
                if (substream == NULL)
                        continue;
                runtime = substream->runtime;
                if (rate < 1000)
                        rate = 1000;
                else if (rate > 192000)
                        rate = 192000;
                if (runtime->oss.rate != rate) {
                        runtime->oss.params = 1;
                        runtime->oss.rate = rate;
                }
        }
        return snd_pcm_oss_get_rate(pcm_oss_file);
}

static int snd_pcm_oss_get_rate(snd_pcm_oss_file_t *pcm_oss_file)
{
        snd_pcm_substream_t *substream;
        int err;
        
        if ((err = snd_pcm_oss_get_active_substream(pcm_oss_file, &substream)) < 0)
                return err;
        return substream->runtime->oss.rate;
}

static int snd_pcm_oss_set_channels(snd_pcm_oss_file_t *pcm_oss_file, unsigned int channels)
{
        int idx;
        if (channels < 1)
                channels = 1;
        if (channels > 128)
                return -EINVAL;
        for (idx = 1; idx >= 0; --idx) {
                snd_pcm_substream_t *substream = pcm_oss_file->streams[idx];
                snd_pcm_runtime_t *runtime;
                if (substream == NULL)
                        continue;
                runtime = substream->runtime;
                if (runtime->oss.channels != channels) {
                        runtime->oss.params = 1;
                        runtime->oss.channels = channels;
                }
        }
        return snd_pcm_oss_get_channels(pcm_oss_file);
}

static int snd_pcm_oss_get_channels(snd_pcm_oss_file_t *pcm_oss_file)
{
        snd_pcm_substream_t *substream;
        int err;
        
        if ((err = snd_pcm_oss_get_active_substream(pcm_oss_file, &substream)) < 0)
                return err;
        return substream->runtime->oss.channels;
}

static int snd_pcm_oss_get_block_size(snd_pcm_oss_file_t *pcm_oss_file)
{
        snd_pcm_substream_t *substream;
        int err;
        
        if ((err = snd_pcm_oss_get_active_substream(pcm_oss_file, &substream)) < 0)
                return err;
        return substream->runtime->oss.period_bytes;
}

static int snd_pcm_oss_get_formats(snd_pcm_oss_file_t *pcm_oss_file)
{
        snd_pcm_substream_t *substream;
        int err;
        int direct;
        snd_pcm_hw_params_t *params;
        unsigned int formats = 0;
        snd_mask_t format_mask;
        int fmt;

        if ((err = snd_pcm_oss_get_active_substream(pcm_oss_file, &substream)) < 0)
                return err;
        if (atomic_read(&substream->runtime->mmap_count)) {
                direct = 1;
        } else {
                snd_pcm_oss_setup_t *setup = substream->oss.setup;
                direct = (setup != NULL && setup->direct);
        }
        if (!direct)
                return AFMT_MU_LAW | AFMT_U8 |
                       AFMT_S16_LE | AFMT_S16_BE |
                       AFMT_S8 | AFMT_U16_LE |
                       AFMT_U16_BE;
        params = kmalloc(sizeof(*params), GFP_KERNEL);
        if (!params)
                return -ENOMEM;
        _snd_pcm_hw_params_any(params);
        err = snd_pcm_hw_refine(substream, params);
        format_mask = *hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT); 
        kfree(params);
        snd_assert(err >= 0, return err);
        for (fmt = 0; fmt < 32; ++fmt) {
                if (snd_mask_test(&format_mask, fmt)) {
                        int f = snd_pcm_oss_format_to(fmt);
                        if (f >= 0)
                                formats |= f;
                }
        }
        return formats;
}

static int snd_pcm_oss_set_format(snd_pcm_oss_file_t *pcm_oss_file, int format)
{
        int formats, idx;
        
        if (format != AFMT_QUERY) {
                formats = snd_pcm_oss_get_formats(pcm_oss_file);
                if (!(formats & format))
                        format = AFMT_U8;
                for (idx = 1; idx >= 0; --idx) {
                        snd_pcm_substream_t *substream = pcm_oss_file->streams[idx];
                        snd_pcm_runtime_t *runtime;
                        if (substream == NULL)
                                continue;
                        runtime = substream->runtime;
                        if (runtime->oss.format != format) {
                                runtime->oss.params = 1;
                                runtime->oss.format = format;
                        }
                }
        }
        return snd_pcm_oss_get_format(pcm_oss_file);
}

static int snd_pcm_oss_get_format(snd_pcm_oss_file_t *pcm_oss_file)
{
        snd_pcm_substream_t *substream;
        int err;
        
        if ((err = snd_pcm_oss_get_active_substream(pcm_oss_file, &substream)) < 0)
                return err;
        return substream->runtime->oss.format;
}

static int snd_pcm_oss_set_subdivide1(snd_pcm_substream_t *substream, int subdivide)
{
        snd_pcm_runtime_t *runtime;

        if (substream == NULL)
                return 0;
        runtime = substream->runtime;
        if (subdivide == 0) {
                subdivide = runtime->oss.subdivision;
                if (subdivide == 0)
                        subdivide = 1;
                return subdivide;
        }
        if (runtime->oss.subdivision || runtime->oss.fragshift)
                return -EINVAL;
        if (subdivide != 1 && subdivide != 2 && subdivide != 4 &&
            subdivide != 8 && subdivide != 16)
                return -EINVAL;
        runtime->oss.subdivision = subdivide;
        runtime->oss.params = 1;
        return subdivide;
}

static int snd_pcm_oss_set_subdivide(snd_pcm_oss_file_t *pcm_oss_file, int subdivide)
{
        int err = -EINVAL, idx;

        for (idx = 1; idx >= 0; --idx) {
                snd_pcm_substream_t *substream = pcm_oss_file->streams[idx];
                if (substream == NULL)
                        continue;
                if ((err = snd_pcm_oss_set_subdivide1(substream, subdivide)) < 0)
                        return err;
        }
        return err;
}

static int snd_pcm_oss_set_fragment1(snd_pcm_substream_t *substream, unsigned int val)
{
        snd_pcm_runtime_t *runtime;

        if (substream == NULL)
                return 0;
        runtime = substream->runtime;
        if (runtime->oss.subdivision || runtime->oss.fragshift)
                return -EINVAL;
        runtime->oss.fragshift = val & 0xffff;
        runtime->oss.maxfrags = (val >> 16) & 0xffff;
        if (runtime->oss.fragshift < 4)         /* < 16 */
                runtime->oss.fragshift = 4;
        if (runtime->oss.maxfrags < 2)
                runtime->oss.maxfrags = 2;
        runtime->oss.params = 1;
        return 0;
}

static int snd_pcm_oss_set_fragment(snd_pcm_oss_file_t *pcm_oss_file, unsigned int val)
{
        int err = -EINVAL, idx;

        for (idx = 1; idx >= 0; --idx) {
                snd_pcm_substream_t *substream = pcm_oss_file->streams[idx];
                if (substream == NULL)
                        continue;
                if ((err = snd_pcm_oss_set_fragment1(substream, val)) < 0)
                        return err;
        }
        return err;
}

static int snd_pcm_oss_nonblock(struct file * file)
{
        file->f_flags |= O_NONBLOCK;
        return 0;
}

static int snd_pcm_oss_get_caps1(snd_pcm_substream_t *substream, int res)
{

        if (substream == NULL) {
                res &= ~DSP_CAP_DUPLEX;
                return res;
        }
#ifdef DSP_CAP_MULTI
        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                if (substream->pstr->substream_count > 1)
                        res |= DSP_CAP_MULTI;
#endif
        /* DSP_CAP_REALTIME is set all times: */
        /* all ALSA drivers can return actual pointer in ring buffer */
#if defined(DSP_CAP_REALTIME) && 0
        {
                snd_pcm_runtime_t *runtime = substream->runtime;
                if (runtime->info & (SNDRV_PCM_INFO_BLOCK_TRANSFER|SNDRV_PCM_INFO_BATCH))
                        res &= ~DSP_CAP_REALTIME;
        }
#endif
        return res;
}

static int snd_pcm_oss_get_caps(snd_pcm_oss_file_t *pcm_oss_file)
{
        int result, idx;
        
        result = DSP_CAP_TRIGGER | DSP_CAP_MMAP | DSP_CAP_DUPLEX | DSP_CAP_REALTIME;
        for (idx = 0; idx < 2; idx++) {
                snd_pcm_substream_t *substream = pcm_oss_file->streams[idx];
                result = snd_pcm_oss_get_caps1(substream, result);
        }
        result |= 0x0001;       /* revision - same as SB AWE 64 */
        return result;
}

static void snd_pcm_oss_simulate_fill(snd_pcm_substream_t *substream, snd_pcm_uframes_t hw_ptr)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        snd_pcm_uframes_t appl_ptr;
        appl_ptr = hw_ptr + runtime->buffer_size;
        appl_ptr %= runtime->boundary;
        runtime->control->appl_ptr = appl_ptr;
}

static int snd_pcm_oss_set_trigger(snd_pcm_oss_file_t *pcm_oss_file, int trigger)
{
        snd_pcm_runtime_t *runtime;
        snd_pcm_substream_t *psubstream = NULL, *csubstream = NULL;
        int err, cmd;

#ifdef OSS_DEBUG
        printk("pcm_oss: trigger = 0x%x\n", trigger);
#endif
        
        psubstream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
        csubstream = pcm_oss_file->streams[SNDRV_PCM_STREAM_CAPTURE];

        if (psubstream) {
                if ((err = snd_pcm_oss_make_ready(psubstream)) < 0)
                        return err;
        }
        if (csubstream) {
                if ((err = snd_pcm_oss_make_ready(csubstream)) < 0)
                        return err;
        }
        if (psubstream) {
                runtime = psubstream->runtime;
                if (trigger & PCM_ENABLE_OUTPUT) {
                        if (runtime->oss.trigger)
                                goto _skip1;
                        if (atomic_read(&psubstream->runtime->mmap_count))
                                snd_pcm_oss_simulate_fill(psubstream, runtime->hw_ptr_interrupt);
                        runtime->oss.trigger = 1;
                        runtime->start_threshold = 1;
                        cmd = SNDRV_PCM_IOCTL_START;
                } else {
                        if (!runtime->oss.trigger)
                                goto _skip1;
                        runtime->oss.trigger = 0;
                        runtime->start_threshold = runtime->boundary;
                        cmd = SNDRV_PCM_IOCTL_DROP;
                        runtime->oss.prepare = 1;
                }
                err = snd_pcm_kernel_playback_ioctl(psubstream, cmd, NULL);
                if (err < 0)
                        return err;
        }
 _skip1:
        if (csubstream) {
                runtime = csubstream->runtime;
                if (trigger & PCM_ENABLE_INPUT) {
                        if (runtime->oss.trigger)
                                goto _skip2;
                        runtime->oss.trigger = 1;
                        runtime->start_threshold = 1;
                        cmd = SNDRV_PCM_IOCTL_START;
                } else {
                        if (!runtime->oss.trigger)
                                goto _skip2;
                        runtime->oss.trigger = 0;
                        runtime->start_threshold = runtime->boundary;
                        cmd = SNDRV_PCM_IOCTL_DROP;
                        runtime->oss.prepare = 1;
                }
                err = snd_pcm_kernel_capture_ioctl(csubstream, cmd, NULL);
                if (err < 0)
                        return err;
        }
 _skip2:
        return 0;
}

static int snd_pcm_oss_get_trigger(snd_pcm_oss_file_t *pcm_oss_file)
{
        snd_pcm_substream_t *psubstream = NULL, *csubstream = NULL;
        int result = 0;

        psubstream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
        csubstream = pcm_oss_file->streams[SNDRV_PCM_STREAM_CAPTURE];
        if (psubstream && psubstream->runtime && psubstream->runtime->oss.trigger)
                result |= PCM_ENABLE_OUTPUT;
        if (csubstream && csubstream->runtime && csubstream->runtime->oss.trigger)
                result |= PCM_ENABLE_INPUT;
        return result;
}

static int snd_pcm_oss_get_odelay(snd_pcm_oss_file_t *pcm_oss_file)
{
        snd_pcm_substream_t *substream;
        snd_pcm_runtime_t *runtime;
        snd_pcm_sframes_t delay;
        int err;

        substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
        if (substream == NULL)
                return -EINVAL;
        if ((err = snd_pcm_oss_make_ready(substream)) < 0)
                return err;
        runtime = substream->runtime;
        if (runtime->oss.params || runtime->oss.prepare)
                return 0;
        err = snd_pcm_kernel_playback_ioctl(substream, SNDRV_PCM_IOCTL_DELAY, &delay);
        if (err == -EPIPE)
                delay = 0;      /* hack for broken OSS applications */
        else if (err < 0)
                return err;
        return snd_pcm_oss_bytes(substream, delay);
}

static int snd_pcm_oss_get_ptr(snd_pcm_oss_file_t *pcm_oss_file, int stream, struct count_info __user * _info)
{       
        snd_pcm_substream_t *substream;
        snd_pcm_runtime_t *runtime;
        snd_pcm_sframes_t delay;
        int fixup;
        struct count_info info;
        int err;

        if (_info == NULL)
                return -EFAULT;
        substream = pcm_oss_file->streams[stream];
        if (substream == NULL)
                return -EINVAL;
        if ((err = snd_pcm_oss_make_ready(substream)) < 0)
                return err;
        runtime = substream->runtime;
        if (runtime->oss.params || runtime->oss.prepare) {
                memset(&info, 0, sizeof(info));
                if (copy_to_user(_info, &info, sizeof(info)))
                        return -EFAULT;
                return 0;
        }
        if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
                err = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_DELAY, &delay);
                if (err == -EPIPE || err == -ESTRPIPE || (! err && delay < 0)) {
                        err = 0;
                        delay = 0;
                        fixup = 0;
                } else {
                        fixup = runtime->oss.buffer_used;
                }
        } else {
                err = snd_pcm_oss_capture_position_fixup(substream, &delay);
                fixup = -runtime->oss.buffer_used;
        }
        if (err < 0)
                return err;
        info.ptr = snd_pcm_oss_bytes(substream, runtime->status->hw_ptr % runtime->buffer_size);
        if (atomic_read(&runtime->mmap_count)) {
                snd_pcm_sframes_t n;
                n = (delay = runtime->hw_ptr_interrupt) - runtime->oss.prev_hw_ptr_interrupt;
                if (n < 0)
                        n += runtime->boundary;
                info.blocks = n / runtime->period_size;
                runtime->oss.prev_hw_ptr_interrupt = delay;
                if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                        snd_pcm_oss_simulate_fill(substream, delay);
                info.bytes = snd_pcm_oss_bytes(substream, runtime->status->hw_ptr) & INT_MAX;
        } else {
                delay = snd_pcm_oss_bytes(substream, delay) + fixup;
                info.blocks = delay / runtime->oss.period_bytes;
                if (stream == SNDRV_PCM_STREAM_PLAYBACK)
                        info.bytes = (runtime->oss.bytes - delay) & INT_MAX;
                else
                        info.bytes = (runtime->oss.bytes + delay) & INT_MAX;
        }
        if (copy_to_user(_info, &info, sizeof(info)))
                return -EFAULT;
        return 0;
}

static int snd_pcm_oss_get_space(snd_pcm_oss_file_t *pcm_oss_file, int stream, struct audio_buf_info __user *_info)
{
        snd_pcm_substream_t *substream;
        snd_pcm_runtime_t *runtime;
        snd_pcm_sframes_t avail;
        int fixup;
        struct audio_buf_info info;
        int err;

        if (_info == NULL)
                return -EFAULT;
        substream = pcm_oss_file->streams[stream];
        if (substream == NULL)
                return -EINVAL;
        runtime = substream->runtime;

        if (runtime->oss.params &&
            (err = snd_pcm_oss_change_params(substream)) < 0)
                return err;

        info.fragsize = runtime->oss.period_bytes;
        info.fragstotal = runtime->periods;
        if (runtime->oss.prepare) {
                if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
                        info.bytes = runtime->oss.period_bytes * runtime->oss.periods;
                        info.fragments = runtime->oss.periods;
                } else {
                        info.bytes = 0;
                        info.fragments = 0;
                }
        } else {
                if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
                        err = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_DELAY, &avail);
                        if (err == -EPIPE || err == -ESTRPIPE || (! err && avail < 0)) {
                                avail = runtime->buffer_size;
                                err = 0;
                                fixup = 0;
                        } else {
                                avail = runtime->buffer_size - avail;
                                fixup = -runtime->oss.buffer_used;
                        }
                } else {
                        err = snd_pcm_oss_capture_position_fixup(substream, &avail);
                        fixup = runtime->oss.buffer_used;
                }
                if (err < 0)
                        return err;
                info.bytes = snd_pcm_oss_bytes(substream, avail) + fixup;
                info.fragments = info.bytes / runtime->oss.period_bytes;
        }

#ifdef OSS_DEBUG
        printk("pcm_oss: space: bytes = %i, fragments = %i, fragstotal = %i, fragsize = %i\n", info.bytes, info.fragments, info.fragstotal, info.fragsize);
#endif
        if (copy_to_user(_info, &info, sizeof(info)))
                return -EFAULT;
        return 0;
}

static int snd_pcm_oss_get_mapbuf(snd_pcm_oss_file_t *pcm_oss_file, int stream, struct buffmem_desc __user * _info)
{
        // it won't be probably implemented
        // snd_printd("TODO: snd_pcm_oss_get_mapbuf\n");
        return -EINVAL;
}

static snd_pcm_oss_setup_t *snd_pcm_oss_look_for_setup(snd_pcm_t *pcm, int stream, const char *task_name)
{
        const char *ptr, *ptrl;
        snd_pcm_oss_setup_t *setup;

        down(&pcm->streams[stream].oss.setup_mutex);
        for (setup = pcm->streams[stream].oss.setup_list; setup; setup = setup->next) {
                if (!strcmp(setup->task_name, task_name)) {
                        up(&pcm->streams[stream].oss.setup_mutex);
                        return setup;
                }
        }
        ptr = ptrl = task_name;
        while (*ptr) {
                if (*ptr == '/')
                        ptrl = ptr + 1;
                ptr++;
        }
        if (ptrl == task_name) {
                goto __not_found;
                return NULL;
        }
        for (setup = pcm->streams[stream].oss.setup_list; setup; setup = setup->next) {
                if (!strcmp(setup->task_name, ptrl)) {
                        up(&pcm->streams[stream].oss.setup_mutex);
                        return setup;
                }
        }
      __not_found:
        up(&pcm->streams[stream].oss.setup_mutex);
        return NULL;
}

static void snd_pcm_oss_init_substream(snd_pcm_substream_t *substream,
                                       snd_pcm_oss_setup_t *setup,
                                       int minor)
{
        snd_pcm_runtime_t *runtime;

        substream->oss.oss = 1;
        substream->oss.setup = setup;
        runtime = substream->runtime;
        runtime->oss.params = 1;
        runtime->oss.trigger = 1;
        runtime->oss.rate = 8000;
        switch (SNDRV_MINOR_OSS_DEVICE(minor)) {
        case SNDRV_MINOR_OSS_PCM_8:
                runtime->oss.format = AFMT_U8;
                break;
        case SNDRV_MINOR_OSS_PCM_16:
                runtime->oss.format = AFMT_S16_LE;
                break;
        default:
                runtime->oss.format = AFMT_MU_LAW;
        }
        runtime->oss.channels = 1;
        runtime->oss.fragshift = 0;
        runtime->oss.maxfrags = 0;
        runtime->oss.subdivision = 0;
}

static void snd_pcm_oss_release_substream(snd_pcm_substream_t *substream)
{
        snd_pcm_runtime_t *runtime;
        runtime = substream->runtime;
        vfree(runtime->oss.buffer);
        snd_pcm_oss_plugin_clear(substream);
        substream->oss.file = NULL;
        substream->oss.oss = 0;
}

static int snd_pcm_oss_release_file(snd_pcm_oss_file_t *pcm_oss_file)
{
        int cidx;
        snd_assert(pcm_oss_file != NULL, return -ENXIO);
        for (cidx = 0; cidx < 2; ++cidx) {
                snd_pcm_substream_t *substream = pcm_oss_file->streams[cidx];
                snd_pcm_runtime_t *runtime;
                if (substream == NULL)
                        continue;
                runtime = substream->runtime;
                
                snd_pcm_stream_lock_irq(substream);
                if (snd_pcm_running(substream))
                        snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
                snd_pcm_stream_unlock_irq(substream);
                if (substream->open_flag) {
                        if (substream->ops->hw_free != NULL)
                                substream->ops->hw_free(substream);
                        substream->ops->close(substream);
                        substream->open_flag = 0;
                }
                substream->ffile = NULL;
                snd_pcm_oss_release_substream(substream);
                snd_pcm_release_substream(substream);
        }
        kfree(pcm_oss_file);
        return 0;
}

static int snd_pcm_oss_open_file(struct file *file,
                                 snd_pcm_t *pcm,
                                 snd_pcm_oss_file_t **rpcm_oss_file,
                                 int minor,
                                 snd_pcm_oss_setup_t *psetup,
                                 snd_pcm_oss_setup_t *csetup)
{
        int err = 0;
        snd_pcm_oss_file_t *pcm_oss_file;
        snd_pcm_substream_t *psubstream = NULL, *csubstream = NULL;
        unsigned int f_mode = file->f_mode;

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

        pcm_oss_file = kcalloc(1, sizeof(*pcm_oss_file), GFP_KERNEL);
        if (pcm_oss_file == NULL)
                return -ENOMEM;

        if ((f_mode & (FMODE_WRITE|FMODE_READ)) == (FMODE_WRITE|FMODE_READ) &&
            (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX))
                f_mode = FMODE_WRITE;
        if ((f_mode & FMODE_WRITE) && !(psetup && psetup->disable)) {
                if ((err = snd_pcm_open_substream(pcm, SNDRV_PCM_STREAM_PLAYBACK,
                                               &psubstream)) < 0) {
                        snd_pcm_oss_release_file(pcm_oss_file);
                        return err;
                }
                pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK] = psubstream;
        }
        if ((f_mode & FMODE_READ) && !(csetup && csetup->disable)) {
                if ((err = snd_pcm_open_substream(pcm, SNDRV_PCM_STREAM_CAPTURE, 
                                               &csubstream)) < 0) {
                        if (!(f_mode & FMODE_WRITE) || err != -ENODEV) {
                                snd_pcm_oss_release_file(pcm_oss_file);
                                return err;
                        } else {
                                csubstream = NULL;
                        }
                }
                pcm_oss_file->streams[SNDRV_PCM_STREAM_CAPTURE] = csubstream;
        }
        
        if (psubstream == NULL && csubstream == NULL) {
                snd_pcm_oss_release_file(pcm_oss_file);
                return -EINVAL;
        }
        if (psubstream != NULL) {
                psubstream->oss.file = pcm_oss_file;
                err = snd_pcm_hw_constraints_init(psubstream);
                if (err < 0) {
                        snd_printd("snd_pcm_hw_constraint_init failed\n");
                        snd_pcm_oss_release_file(pcm_oss_file);
                        return err;
                }
                if ((err = psubstream->ops->open(psubstream)) < 0) {
                        snd_pcm_oss_release_file(pcm_oss_file);
                        return err;
                }
                psubstream->open_flag = 1;
                err = snd_pcm_hw_constraints_complete(psubstream);
                if (err < 0) {
                        snd_printd("snd_pcm_hw_constraint_complete failed\n");
                        snd_pcm_oss_release_file(pcm_oss_file);
                        return err;
                }
                psubstream->ffile = file;
                snd_pcm_oss_init_substream(psubstream, psetup, minor);
        }
        if (csubstream != NULL) {
                csubstream->oss.file = pcm_oss_file;
                err = snd_pcm_hw_constraints_init(csubstream);
                if (err < 0) {
                        snd_printd("snd_pcm_hw_constraint_init failed\n");
                        snd_pcm_oss_release_file(pcm_oss_file);
                        return err;
                }
                if ((err = csubstream->ops->open(csubstream)) < 0) {
                        snd_pcm_oss_release_file(pcm_oss_file);
                        return err;
                }
                csubstream->open_flag = 1;
                err = snd_pcm_hw_constraints_complete(csubstream);
                if (err < 0) {
                        snd_printd("snd_pcm_hw_constraint_complete failed\n");
                        snd_pcm_oss_release_file(pcm_oss_file);
                        return err;
                }
                csubstream->ffile = file;
                snd_pcm_oss_init_substream(csubstream, csetup, minor);
        }

        file->private_data = pcm_oss_file;
        *rpcm_oss_file = pcm_oss_file;
        return 0;
}


static int snd_pcm_oss_open(struct inode *inode, struct file *file)
{
        int minor = iminor(inode);
        int cardnum = SNDRV_MINOR_OSS_CARD(minor);
        int device;
        int err;
        char task_name[32];
        snd_pcm_t *pcm;
        snd_pcm_oss_file_t *pcm_oss_file;
        snd_pcm_oss_setup_t *psetup = NULL, *csetup = NULL;
        int nonblock;
        wait_queue_t wait;

        snd_assert(cardnum >= 0 && cardnum < SNDRV_CARDS, return -ENXIO);
        device = SNDRV_MINOR_OSS_DEVICE(minor) == SNDRV_MINOR_OSS_PCM1 ?
                adsp_map[cardnum] : dsp_map[cardnum];

        pcm = snd_pcm_devices[(cardnum * SNDRV_PCM_DEVICES) + device];
        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;
        }
        if (snd_task_name(current, task_name, sizeof(task_name)) < 0) {
                err = -EFAULT;
                goto __error;
        }
        if (file->f_mode & FMODE_WRITE)
                psetup = snd_pcm_oss_look_for_setup(pcm, SNDRV_PCM_STREAM_PLAYBACK, task_name);
        if (file->f_mode & FMODE_READ)
                csetup = snd_pcm_oss_look_for_setup(pcm, SNDRV_PCM_STREAM_CAPTURE, task_name);

        nonblock = !!(file->f_flags & O_NONBLOCK);
        if (psetup && !psetup->disable) {
                if (psetup->nonblock)
                        nonblock = 1;
                else if (psetup->block)
                        nonblock = 0;
        } else if (csetup && !csetup->disable) {
                if (csetup->nonblock)
                        nonblock = 1;
                else if (csetup->block)
                        nonblock = 0;
        }
        if (!nonblock)
                nonblock = nonblock_open;

        init_waitqueue_entry(&wait, current);
        add_wait_queue(&pcm->open_wait, &wait);
        down(&pcm->open_mutex);
        while (1) {
                err = snd_pcm_oss_open_file(file, pcm, &pcm_oss_file,
                                            minor, psetup, csetup);
                if (err >= 0)
                        break;
                if (err == -EAGAIN) {
                        if (nonblock) {
                                err = -EBUSY;
                                break;
                        }
                } else
                        break;
                set_current_state(TASK_INTERRUPTIBLE);
                up(&pcm->open_mutex);
                schedule();
                down(&pcm->open_mutex);
                if (signal_pending(current)) {
                        err = -ERESTARTSYS;
                        break;
                }
        }
        remove_wait_queue(&pcm->open_wait, &wait);
        up(&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_oss_release(struct inode *inode, struct file *file)
{
        snd_pcm_t *pcm;
        snd_pcm_substream_t *substream;
        snd_pcm_oss_file_t *pcm_oss_file;

        pcm_oss_file = file->private_data;
        substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
        if (substream == NULL)
                substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_CAPTURE];
        snd_assert(substream != NULL, return -ENXIO);
        pcm = substream->pcm;
        snd_pcm_oss_sync(pcm_oss_file);
        down(&pcm->open_mutex);
        snd_pcm_oss_release_file(pcm_oss_file);
        up(&pcm->open_mutex);
        wake_up(&pcm->open_wait);
        module_put(pcm->card->module);
        snd_card_file_remove(pcm->card, file);
        return 0;
}

static inline int _snd_pcm_oss_ioctl(struct inode *inode, struct file *file,
                                     unsigned int cmd, unsigned long arg)
{
        snd_pcm_oss_file_t *pcm_oss_file;
        int __user *p = (int __user *)arg;
        int res;

        pcm_oss_file = file->private_data;
        if (cmd == OSS_GETVERSION)
                return put_user(SNDRV_OSS_VERSION, p);
        if (cmd == OSS_ALSAEMULVER)
                return put_user(1, p);
#if defined(CONFIG_SND_MIXER_OSS) || (defined(MODULE) && defined(CONFIG_SND_MIXER_OSS_MODULE))
        if (((cmd >> 8) & 0xff) == 'M') {       /* mixer ioctl - for OSS compatibility */
                snd_pcm_substream_t *substream;
                int idx;
                for (idx = 0; idx < 2; ++idx) {
                        substream = pcm_oss_file->streams[idx];
                        if (substream != NULL)
                                break;
                }
                snd_assert(substream != NULL, return -ENXIO);
                return snd_mixer_oss_ioctl_card(substream->pcm->card, cmd, arg);
        }
#endif
        if (((cmd >> 8) & 0xff) != 'P')
                return -EINVAL;
#ifdef OSS_DEBUG
        printk("pcm_oss: ioctl = 0x%x\n", cmd);
#endif
        switch (cmd) {
        case SNDCTL_DSP_RESET:
                return snd_pcm_oss_reset(pcm_oss_file);
        case SNDCTL_DSP_SYNC:
                return snd_pcm_oss_sync(pcm_oss_file);
        case SNDCTL_DSP_SPEED:
                if (get_user(res, p))
                        return -EFAULT;
                if ((res = snd_pcm_oss_set_rate(pcm_oss_file, res))<0)
                        return res;
                return put_user(res, p);
        case SOUND_PCM_READ_RATE:
                res = snd_pcm_oss_get_rate(pcm_oss_file);
                if (res < 0)
                        return res;
                return put_user(res, p);
        case SNDCTL_DSP_STEREO:
                if (get_user(res, p))
                        return -EFAULT;
                res = res > 0 ? 2 : 1;
                if ((res = snd_pcm_oss_set_channels(pcm_oss_file, res)) < 0)
                        return res;
                return put_user(--res, p);
        case SNDCTL_DSP_GETBLKSIZE:
                res = snd_pcm_oss_get_block_size(pcm_oss_file);
                if (res < 0)
                        return res;
                return put_user(res, p);
        case SNDCTL_DSP_SETFMT:
                if (get_user(res, p))
                        return -EFAULT;
                res = snd_pcm_oss_set_format(pcm_oss_file, res);
                if (res < 0)
                        return res;
                return put_user(res, p);
        case SOUND_PCM_READ_BITS:
                res = snd_pcm_oss_get_format(pcm_oss_file);
                if (res < 0)
                        return res;
                return put_user(res, p);
        case SNDCTL_DSP_CHANNELS:
                if (get_user(res, p))
                        return -EFAULT;
                res = snd_pcm_oss_set_channels(pcm_oss_file, res);
                if (res < 0)
                        return res;
                return put_user(res, p);
        case SOUND_PCM_READ_CHANNELS:
                res = snd_pcm_oss_get_channels(pcm_oss_file);
                if (res < 0)
                        return res;
                return put_user(res, p);
        case SOUND_PCM_WRITE_FILTER:
        case SOUND_PCM_READ_FILTER:
                return -EIO;

        case SNDCTL_DSP_POST:
                return snd_pcm_oss_post(pcm_oss_file);
        case SNDCTL_DSP_SUBDIVIDE:
                if (get_user(res, p))
                        return -EFAULT;
                res = snd_pcm_oss_set_subdivide(pcm_oss_file, res);
                if (res < 0)
                        return res;
                return put_user(res, p);
        case SNDCTL_DSP_SETFRAGMENT:
                if (get_user(res, p))
                        return -EFAULT;
                return snd_pcm_oss_set_fragment(pcm_oss_file, res);
        case SNDCTL_DSP_GETFMTS:
                res = snd_pcm_oss_get_formats(pcm_oss_file);
                if (res < 0)
                        return res;
                return put_user(res, p);
        case SNDCTL_DSP_GETOSPACE:
        case SNDCTL_DSP_GETISPACE:
                return snd_pcm_oss_get_space(pcm_oss_file,
                        cmd == SNDCTL_DSP_GETISPACE ?
                                SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK,
                        (struct audio_buf_info __user *) arg);
        case SNDCTL_DSP_NONBLOCK:
                return snd_pcm_oss_nonblock(file);
        case SNDCTL_DSP_GETCAPS:
                res = snd_pcm_oss_get_caps(pcm_oss_file);
                if (res < 0)
                        return res;
                return put_user(res, p);
        case SNDCTL_DSP_GETTRIGGER:
                res = snd_pcm_oss_get_trigger(pcm_oss_file);
                if (res < 0)
                        return res;
                return put_user(res, p);
        case SNDCTL_DSP_SETTRIGGER:
                if (get_user(res, p))
                        return -EFAULT;
                return snd_pcm_oss_set_trigger(pcm_oss_file, res);
        case SNDCTL_DSP_GETIPTR:
        case SNDCTL_DSP_GETOPTR:
                return snd_pcm_oss_get_ptr(pcm_oss_file,
                        cmd == SNDCTL_DSP_GETIPTR ?
                                SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK,
                        (struct count_info __user *) arg);
        case SNDCTL_DSP_MAPINBUF:
        case SNDCTL_DSP_MAPOUTBUF:
                return snd_pcm_oss_get_mapbuf(pcm_oss_file,
                        cmd == SNDCTL_DSP_MAPINBUF ?
                                SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK,
                        (struct buffmem_desc __user *) arg);
        case SNDCTL_DSP_SETSYNCRO:
                /* stop DMA now.. */
                return 0;
        case SNDCTL_DSP_SETDUPLEX:
                if (snd_pcm_oss_get_caps(pcm_oss_file) & DSP_CAP_DUPLEX)
                        return 0;
                return -EIO;
        case SNDCTL_DSP_GETODELAY:
                res = snd_pcm_oss_get_odelay(pcm_oss_file);
                if (res < 0) {
                        /* it's for sure, some broken apps don't check for error codes */
                        put_user(0, p);
                        return res;
                }
                return put_user(res, p);
        case SNDCTL_DSP_PROFILE:
                return 0;       /* silently ignore */
        default:
                snd_printd("pcm_oss: unknown command = 0x%x\n", cmd);
        }
        return -EINVAL;
}

/* FIXME: need to unlock BKL to allow preemption */
static int snd_pcm_oss_ioctl(struct inode *inode, struct file *file,
                             unsigned int cmd, unsigned long arg)
{
        int err;
        unlock_kernel();
        err = _snd_pcm_oss_ioctl(inode, file, cmd, arg);
        lock_kernel();
        return err;
}

static ssize_t snd_pcm_oss_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
{
        snd_pcm_oss_file_t *pcm_oss_file;
        snd_pcm_substream_t *substream;

        pcm_oss_file = file->private_data;
        substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_CAPTURE];
        if (substream == NULL)
                return -ENXIO;
#ifndef OSS_DEBUG
        return snd_pcm_oss_read1(substream, buf, count);
#else
        {
                ssize_t res = snd_pcm_oss_read1(substream, buf, count);
                printk("pcm_oss: read %li bytes (returned %li bytes)\n", (long)count, (long)res);
                return res;
        }
#endif
}

static ssize_t snd_pcm_oss_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
{
        snd_pcm_oss_file_t *pcm_oss_file;
        snd_pcm_substream_t *substream;
        long result;

        pcm_oss_file = file->private_data;
        substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
        if (substream == NULL)
                return -ENXIO;
        up(&file->f_dentry->d_inode->i_sem);
        result = snd_pcm_oss_write1(substream, buf, count);
        down(&file->f_dentry->d_inode->i_sem);
#ifdef OSS_DEBUG
        printk("pcm_oss: write %li bytes (wrote %li bytes)\n", (long)count, (long)result);
#endif
        return result;
}

static int snd_pcm_oss_playback_ready(snd_pcm_substream_t *substream)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        if (atomic_read(&runtime->mmap_count))
                return runtime->oss.prev_hw_ptr_interrupt != runtime->hw_ptr_interrupt;
        else
                return snd_pcm_playback_avail(runtime) >= runtime->oss.period_frames;
}

static int snd_pcm_oss_capture_ready(snd_pcm_substream_t *substream)
{
        snd_pcm_runtime_t *runtime = substream->runtime;
        if (atomic_read(&runtime->mmap_count))
                return runtime->oss.prev_hw_ptr_interrupt != runtime->hw_ptr_interrupt;
        else
                return snd_pcm_capture_avail(runtime) >= runtime->oss.period_frames;
}

static unsigned int snd_pcm_oss_poll(struct file *file, poll_table * wait)
{
        snd_pcm_oss_file_t *pcm_oss_file;
        unsigned int mask;
        snd_pcm_substream_t *psubstream = NULL, *csubstream = NULL;
        
        pcm_oss_file = file->private_data;

        psubstream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
        csubstream = pcm_oss_file->streams[SNDRV_PCM_STREAM_CAPTURE];

        mask = 0;
        if (psubstream != NULL) {
                snd_pcm_runtime_t *runtime = psubstream->runtime;
                poll_wait(file, &runtime->sleep, wait);
                snd_pcm_stream_lock_irq(psubstream);
                if (runtime->status->state != SNDRV_PCM_STATE_DRAINING &&
                    (runtime->status->state != SNDRV_PCM_STATE_RUNNING ||
                     snd_pcm_oss_playback_ready(psubstream)))
                        mask |= POLLOUT | POLLWRNORM;
                snd_pcm_stream_unlock_irq(psubstream);
        }
        if (csubstream != NULL) {
                snd_pcm_runtime_t *runtime = csubstream->runtime;
                enum sndrv_pcm_state ostate;
                poll_wait(file, &runtime->sleep, wait);
                snd_pcm_stream_lock_irq(csubstream);
                if ((ostate = runtime->status->state) != SNDRV_PCM_STATE_RUNNING ||
                    snd_pcm_oss_capture_ready(csubstream))
                        mask |= POLLIN | POLLRDNORM;
                snd_pcm_stream_unlock_irq(csubstream);
                if (ostate != SNDRV_PCM_STATE_RUNNING && runtime->oss.trigger) {
                        snd_pcm_oss_file_t ofile;
                        memset(&ofile, 0, sizeof(ofile));
                        ofile.streams[SNDRV_PCM_STREAM_CAPTURE] = pcm_oss_file->streams[SNDRV_PCM_STREAM_CAPTURE];
                        runtime->oss.trigger = 0;
                        snd_pcm_oss_set_trigger(&ofile, PCM_ENABLE_INPUT);
                }
        }

        return mask;
}

static int snd_pcm_oss_mmap(struct file *file, struct vm_area_struct *area)
{
        snd_pcm_oss_file_t *pcm_oss_file;
        snd_pcm_substream_t *substream = NULL;
        snd_pcm_runtime_t *runtime;
        int err;

#ifdef OSS_DEBUG
        printk("pcm_oss: mmap begin\n");
#endif
        pcm_oss_file = file->private_data;
        switch ((area->vm_flags & (VM_READ | VM_WRITE))) {
        case VM_READ | VM_WRITE:
                substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
                if (substream)
                        break;
                /* Fall through */
        case VM_READ:
                substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_CAPTURE];
                break;
        case VM_WRITE:
                substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
                break;
        default:
                return -EINVAL;
        }
        /* set VM_READ access as well to fix memset() routines that do
           reads before writes (to improve performance) */
        area->vm_flags |= VM_READ;
        if (substream == NULL)
                return -ENXIO;
        runtime = substream->runtime;
        if (!(runtime->info & SNDRV_PCM_INFO_MMAP_VALID))
                return -EIO;
        if (runtime->info & SNDRV_PCM_INFO_INTERLEAVED)
                runtime->access = SNDRV_PCM_ACCESS_MMAP_INTERLEAVED;
        else
                return -EIO;
        
        if (runtime->oss.params) {
                if ((err = snd_pcm_oss_change_params(substream)) < 0)
                        return err;
        }
        if (runtime->oss.plugin_first != NULL)
                return -EIO;

        if (area->vm_pgoff != 0)
                return -EINVAL;

        err = snd_pcm_mmap_data(substream, file, area);
        if (err < 0)
                return err;
        runtime->oss.mmap_bytes = area->vm_end - area->vm_start;
        runtime->silence_threshold = 0;
        runtime->silence_size = 0;
#ifdef OSS_DEBUG
        printk("pcm_oss: mmap ok, bytes = 0x%x\n", runtime->oss.mmap_bytes);
#endif
        /* In mmap mode we never stop */
        runtime->stop_threshold = runtime->boundary;

        return 0;
}

/*
 *  /proc interface
 */

static void snd_pcm_oss_proc_read(snd_info_entry_t *entry,
                                  snd_info_buffer_t * buffer)
{
        snd_pcm_str_t *pstr = (snd_pcm_str_t *)entry->private_data;
        snd_pcm_oss_setup_t *setup = pstr->oss.setup_list;
        down(&pstr->oss.setup_mutex);
        while (setup) {
                snd_iprintf(buffer, "%s %u %u%s%s%s%s%s%s\n",
                            setup->task_name,
                            setup->periods,
                            setup->period_size,
                            setup->disable ? " disable" : "",
                            setup->direct ? " direct" : "",
                            setup->block ? " block" : "",
                            setup->nonblock ? " non-block" : "",
                            setup->partialfrag ? " partial-frag" : "",
                            setup->nosilence ? " no-silence" : "");
                setup = setup->next;
        }
        up(&pstr->oss.setup_mutex);
}

static void snd_pcm_oss_proc_free_setup_list(snd_pcm_str_t * pstr)
{
        unsigned int idx;
        snd_pcm_substream_t *substream;
        snd_pcm_oss_setup_t *setup, *setupn;

        for (idx = 0, substream = pstr->substream;
             idx < pstr->substream_count; idx++, substream = substream->next)
                substream->oss.setup = NULL;
        for (setup = pstr->oss.setup_list, pstr->oss.setup_list = NULL;
             setup; setup = setupn) {
                setupn = setup->next;
                kfree(setup->task_name);
                kfree(setup);
        }
        pstr->oss.setup_list = NULL;
}

static void snd_pcm_oss_proc_write(snd_info_entry_t *entry,
                                   snd_info_buffer_t * buffer)
{
        snd_pcm_str_t *pstr = (snd_pcm_str_t *)entry->private_data;
        char line[256], str[32], task_name[32], *ptr;
        int idx1;
        snd_pcm_oss_setup_t *setup, *setup1, template;

        while (!snd_info_get_line(buffer, line, sizeof(line))) {
                down(&pstr->oss.setup_mutex);
                memset(&template, 0, sizeof(template));
                ptr = snd_info_get_str(task_name, line, sizeof(task_name));
                if (!strcmp(task_name, "clear") || !strcmp(task_name, "erase")) {
                        snd_pcm_oss_proc_free_setup_list(pstr);
                        up(&pstr->oss.setup_mutex);
                        continue;
                }
                for (setup = pstr->oss.setup_list; setup; setup = setup->next) {
                        if (!strcmp(setup->task_name, task_name)) {
                                template = *setup;
                                break;
                        }
                }
                ptr = snd_info_get_str(str, ptr, sizeof(str));
                template.periods = simple_strtoul(str, NULL, 10);
                ptr = snd_info_get_str(str, ptr, sizeof(str));
                template.period_size = simple_strtoul(str, NULL, 10);
                for (idx1 = 31; idx1 >= 0; idx1--)
                        if (template.period_size & (1 << idx1))
                                break;
                for (idx1--; idx1 >= 0; idx1--)
                        template.period_size &= ~(1 << idx1);
                do {
                        ptr = snd_info_get_str(str, ptr, sizeof(str));
                        if (!strcmp(str, "disable")) {
                                template.disable = 1;
                        } else if (!strcmp(str, "direct")) {
                                template.direct = 1;
                        } else if (!strcmp(str, "block")) {
                                template.block = 1;
                        } else if (!strcmp(str, "non-block")) {
                                template.nonblock = 1;
                        } else if (!strcmp(str, "partial-frag")) {
                                template.partialfrag = 1;
                        } else if (!strcmp(str, "no-silence")) {
                                template.nosilence = 1;
                        }
                } while (*str);
                if (setup == NULL) {
                        setup = (snd_pcm_oss_setup_t *) kmalloc(sizeof(snd_pcm_oss_setup_t), GFP_KERNEL);
                        if (setup) {
                                if (pstr->oss.setup_list == NULL) {
                                        pstr->oss.setup_list = setup;
                                } else {
                                        for (setup1 = pstr->oss.setup_list; setup1->next; setup1 = setup1->next);
                                        setup1->next = setup;
                                }
                                template.task_name = snd_kmalloc_strdup(task_name, GFP_KERNEL);
                        } else {
                                buffer->error = -ENOMEM;
                        }
                }
                if (setup)
                        *setup = template;
                up(&pstr->oss.setup_mutex);
        }
}

static void snd_pcm_oss_proc_init(snd_pcm_t *pcm)
{
        int stream;
        for (stream = 0; stream < 2; ++stream) {
                snd_info_entry_t *entry;
                snd_pcm_str_t *pstr = &pcm->streams[stream];
                if (pstr->substream_count == 0)
                        continue;
                if ((entry = snd_info_create_card_entry(pcm->card, "oss", pstr->proc_root)) != NULL) {
                        entry->content = SNDRV_INFO_CONTENT_TEXT;
                        entry->mode = S_IFREG | S_IRUGO | S_IWUSR;
                        entry->c.text.read_size = 8192;
                        entry->c.text.read = snd_pcm_oss_proc_read;
                        entry->c.text.write_size = 8192;
                        entry->c.text.write = snd_pcm_oss_proc_write;
                        entry->private_data = pstr;
                        if (snd_info_register(entry) < 0) {
                                snd_info_free_entry(entry);
                                entry = NULL;
                        }
                }
                pstr->oss.proc_entry = entry;
        }
}

static void snd_pcm_oss_proc_done(snd_pcm_t *pcm)
{
        int stream;
        for (stream = 0; stream < 2; ++stream) {
                snd_pcm_str_t *pstr = &pcm->streams[stream];
                if (pstr->oss.proc_entry) {
                        snd_info_unregister(pstr->oss.proc_entry);
                        pstr->oss.proc_entry = NULL;
                        snd_pcm_oss_proc_free_setup_list(pstr);
                }
        }
}

/*
 *  ENTRY functions
 */

static struct file_operations snd_pcm_oss_f_reg =
{
        .owner =        THIS_MODULE,
        .read =         snd_pcm_oss_read,
        .write =        snd_pcm_oss_write,
        .open =         snd_pcm_oss_open,
        .release =      snd_pcm_oss_release,
        .poll =         snd_pcm_oss_poll,
        .ioctl =        snd_pcm_oss_ioctl,
        .mmap =         snd_pcm_oss_mmap,
};

static snd_minor_t snd_pcm_oss_reg =
{
        .comment =      "digital audio",
        .f_ops =        &snd_pcm_oss_f_reg,
};

static void register_oss_dsp(snd_pcm_t *pcm, int index)
{
        char name[128];
        sprintf(name, "dsp%i%i", pcm->card->number, pcm->device);
        if (snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_PCM,
                                    pcm->card, index, &snd_pcm_oss_reg,
                                    name) < 0) {
                snd_printk("unable to register OSS PCM device %i:%i\n", pcm->card->number, pcm->device);
        }
}

static int snd_pcm_oss_register_minor(snd_pcm_t * pcm)
{
        pcm->oss.reg = 0;
        if (dsp_map[pcm->card->number] == (int)pcm->device) {
                char name[128];
                int duplex;
                register_oss_dsp(pcm, 0);
                duplex = (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count > 0 && 
                              pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count && 
                              !(pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX));
                sprintf(name, "%s%s", pcm->name, duplex ? " (DUPLEX)" : "");
#ifdef SNDRV_OSS_INFO_DEV_AUDIO
                snd_oss_info_register(SNDRV_OSS_INFO_DEV_AUDIO,
                                      pcm->card->number,
                                      name);
#endif
                pcm->oss.reg++;
                pcm->oss.reg_mask |= 1;
        }
        if (adsp_map[pcm->card->number] == (int)pcm->device) {
                register_oss_dsp(pcm, 1);
                pcm->oss.reg++;
                pcm->oss.reg_mask |= 2;
        }

        if (pcm->oss.reg)
                snd_pcm_oss_proc_init(pcm);

        return 0;
}

static int snd_pcm_oss_disconnect_minor(snd_pcm_t * pcm)
{
        if (pcm->oss.reg) {
                if (pcm->oss.reg_mask & 1) {
                        pcm->oss.reg_mask &= ~1;
                        snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_PCM,
                                                  pcm->card, 0);
                }
                if (pcm->oss.reg_mask & 2) {
                        pcm->oss.reg_mask &= ~2;
                        snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_PCM,
                                                  pcm->card, 1);
                }
        }
        return 0;
}

static int snd_pcm_oss_unregister_minor(snd_pcm_t * pcm)
{
        snd_pcm_oss_disconnect_minor(pcm);
        if (pcm->oss.reg) {
                if (dsp_map[pcm->card->number] == (int)pcm->device) {
#ifdef SNDRV_OSS_INFO_DEV_AUDIO
                        snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_AUDIO, pcm->card->number);
#endif
                }
                pcm->oss.reg = 0;
                snd_pcm_oss_proc_done(pcm);
        }
        return 0;
}

static snd_pcm_notify_t snd_pcm_oss_notify =
{
        .n_register =   snd_pcm_oss_register_minor,
        .n_disconnect = snd_pcm_oss_disconnect_minor,
        .n_unregister = snd_pcm_oss_unregister_minor,
};

static int __init alsa_pcm_oss_init(void)
{
        int i;
        int err;

        /* check device map table */
        for (i = 0; i < SNDRV_CARDS; i++) {
                if (dsp_map[i] < 0 || dsp_map[i] >= SNDRV_PCM_DEVICES) {
                        snd_printk("invalid dsp_map[%d] = %d\n", i, dsp_map[i]);
                        dsp_map[i] = 0;
                }
                if (adsp_map[i] < 0 || adsp_map[i] >= SNDRV_PCM_DEVICES) {
                        snd_printk("invalid adsp_map[%d] = %d\n", i, adsp_map[i]);
                        adsp_map[i] = 1;
                }
        }
        if ((err = snd_pcm_notify(&snd_pcm_oss_notify, 0)) < 0)
                return err;
        return 0;
}

static void __exit alsa_pcm_oss_exit(void)
{
        snd_pcm_notify(&snd_pcm_oss_notify, 1);
}

module_init(alsa_pcm_oss_init)
module_exit(alsa_pcm_oss_exit)