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This ensures they are emitted in .data.rel.ro rather than .data.rel, which should make a nice difference when using prelink. Signed-off-by: Diego E. 'Flameeyes' Pettenò <flameeyes@gmail.com>
813 lines
23 KiB
C
813 lines
23 KiB
C
/**
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* \file pcm/pcm_extplug.c
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* \ingroup Plugin_SDK
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* \brief External Filter Plugin SDK
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* \author Takashi Iwai <tiwai@suse.de>
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* \date 2005
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*/
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/*
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* PCM - External Filter Plugin SDK
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* Copyright (c) 2005 by Takashi Iwai <tiwai@suse.de>
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*
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*
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* This library is free software; you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License as
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* published by the Free Software Foundation; either version 2.1 of
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* the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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*/
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#include "pcm_local.h"
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#include "pcm_plugin.h"
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#include "pcm_extplug.h"
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#include "pcm_ext_parm.h"
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#ifndef PIC
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/* entry for static linking */
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const char *_snd_module_pcm_extplug = "";
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#endif
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#ifndef DOC_HIDDEN
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typedef struct snd_pcm_extplug_priv {
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snd_pcm_plugin_t plug;
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snd_pcm_extplug_t *data;
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struct snd_ext_parm params[SND_PCM_EXTPLUG_HW_PARAMS];
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struct snd_ext_parm sparams[SND_PCM_EXTPLUG_HW_PARAMS];
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} extplug_priv_t;
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static const int hw_params_type[SND_PCM_EXTPLUG_HW_PARAMS] = {
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[SND_PCM_EXTPLUG_HW_FORMAT] = SND_PCM_HW_PARAM_FORMAT,
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[SND_PCM_EXTPLUG_HW_CHANNELS] = SND_PCM_HW_PARAM_CHANNELS
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};
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#define is_mask_type(i) (hw_params_type[i] < SND_PCM_HW_PARAM_FIRST_INTERVAL)
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static const unsigned int excl_parbits[SND_PCM_EXTPLUG_HW_PARAMS] = {
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[SND_PCM_EXTPLUG_HW_FORMAT] = (SND_PCM_HW_PARBIT_FORMAT|
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SND_PCM_HW_PARBIT_SUBFORMAT |
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SND_PCM_HW_PARBIT_SAMPLE_BITS),
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[SND_PCM_EXTPLUG_HW_CHANNELS] = (SND_PCM_HW_PARBIT_CHANNELS|
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SND_PCM_HW_PARBIT_FRAME_BITS),
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};
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/*
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* set min/max values for the given parameter
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*/
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int snd_ext_parm_set_minmax(struct snd_ext_parm *parm, unsigned int min, unsigned int max)
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{
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parm->num_list = 0;
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free(parm->list);
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parm->list = NULL;
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parm->min = min;
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parm->max = max;
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parm->active = 1;
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return 0;
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}
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/*
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* set the list of available values for the given parameter
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*/
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static int val_compar(const void *ap, const void *bp)
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{
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return *(const unsigned int *)ap - *(const unsigned int *)bp;
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}
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int snd_ext_parm_set_list(struct snd_ext_parm *parm, unsigned int num_list, const unsigned int *list)
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{
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unsigned int *new_list;
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new_list = malloc(sizeof(*new_list) * num_list);
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if (new_list == NULL)
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return -ENOMEM;
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memcpy(new_list, list, sizeof(*new_list) * num_list);
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qsort(new_list, num_list, sizeof(*new_list), val_compar);
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free(parm->list);
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parm->num_list = num_list;
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parm->list = new_list;
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parm->active = 1;
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return 0;
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}
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void snd_ext_parm_clear(struct snd_ext_parm *parm)
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{
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free(parm->list);
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memset(parm, 0, sizeof(*parm));
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}
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/*
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* limit the interval to the given list
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*/
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int snd_interval_list(snd_interval_t *ival, int num_list, unsigned int *list)
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{
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int imin, imax;
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int changed = 0;
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if (snd_interval_empty(ival))
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return -ENOENT;
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for (imin = 0; imin < num_list; imin++) {
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if (ival->min == list[imin] && ! ival->openmin)
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break;
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if (ival->min <= list[imin]) {
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ival->min = list[imin];
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ival->openmin = 0;
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changed = 1;
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break;
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}
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}
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if (imin >= num_list)
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return -EINVAL;
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for (imax = num_list - 1; imax >= imin; imax--) {
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if (ival->max == list[imax] && ! ival->openmax)
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break;
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if (ival->max >= list[imax]) {
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ival->max = list[imax];
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ival->openmax = 0;
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changed = 1;
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break;
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}
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}
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if (imax < imin)
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return -EINVAL;
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return changed;
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}
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/*
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* refine the interval parameter
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*/
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int snd_ext_parm_interval_refine(snd_interval_t *ival, struct snd_ext_parm *parm, int type)
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{
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parm += type;
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if (! parm->active)
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return 0;
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ival->integer |= parm->integer;
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if (parm->num_list) {
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return snd_interval_list(ival, parm->num_list, parm->list);
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} else if (parm->min || parm->max) {
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snd_interval_t t;
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memset(&t, 0, sizeof(t));
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snd_interval_set_minmax(&t, parm->min, parm->max);
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t.integer = ival->integer;
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return snd_interval_refine(ival, &t);
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}
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return 0;
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}
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/*
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* refine the mask parameter
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*/
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int snd_ext_parm_mask_refine(snd_mask_t *mask, struct snd_ext_parm *parm, int type)
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{
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snd_mask_t bits;
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unsigned int i;
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parm += type;
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memset(&bits, 0, sizeof(bits));
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for (i = 0; i < parm->num_list; i++)
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bits.bits[parm->list[i] / 32] |= 1U << (parm->list[i] % 32);
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return snd_mask_refine(mask, &bits);
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}
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/*
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* hw_refine callback
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*/
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static int extplug_hw_refine(snd_pcm_hw_params_t *hw_params,
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struct snd_ext_parm *parm)
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{
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int i, err, change = 0;
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for (i = 0; i < SND_PCM_EXTPLUG_HW_PARAMS; i++) {
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int type = hw_params_type[i];
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if (is_mask_type(i))
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err = snd_ext_parm_mask_refine(hw_param_mask(hw_params, type),
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parm, i);
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else
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err = snd_ext_parm_interval_refine(hw_param_interval(hw_params, type),
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parm, i);
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if (err < 0)
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return err;
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change |= err;
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}
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return change;
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}
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static int snd_pcm_extplug_hw_refine_cprepare(snd_pcm_t *pcm,
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snd_pcm_hw_params_t *params)
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{
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extplug_priv_t *ext = pcm->private_data;
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int err;
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snd_pcm_access_mask_t access_mask = { SND_PCM_ACCBIT_SHM };
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err = _snd_pcm_hw_param_set_mask(params, SND_PCM_HW_PARAM_ACCESS,
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&access_mask);
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if (err < 0)
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return err;
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err = extplug_hw_refine(params, ext->params);
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if (err < 0)
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return err;
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params->info &= ~(SND_PCM_INFO_MMAP | SND_PCM_INFO_MMAP_VALID);
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return 0;
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}
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static int snd_pcm_extplug_hw_refine_sprepare(snd_pcm_t *pcm,
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snd_pcm_hw_params_t *sparams)
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{
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extplug_priv_t *ext = pcm->private_data;
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snd_pcm_access_mask_t saccess_mask = { SND_PCM_ACCBIT_MMAP };
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_snd_pcm_hw_params_any(sparams);
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_snd_pcm_hw_param_set_mask(sparams, SND_PCM_HW_PARAM_ACCESS,
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&saccess_mask);
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extplug_hw_refine(sparams, ext->sparams);
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return 0;
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}
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static unsigned int get_links(struct snd_ext_parm *params)
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{
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int i;
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unsigned int links = (SND_PCM_HW_PARBIT_FORMAT |
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SND_PCM_HW_PARBIT_SUBFORMAT |
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SND_PCM_HW_PARBIT_SAMPLE_BITS |
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SND_PCM_HW_PARBIT_CHANNELS |
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SND_PCM_HW_PARBIT_FRAME_BITS |
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SND_PCM_HW_PARBIT_RATE |
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SND_PCM_HW_PARBIT_PERIODS |
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SND_PCM_HW_PARBIT_PERIOD_SIZE |
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SND_PCM_HW_PARBIT_PERIOD_TIME |
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SND_PCM_HW_PARBIT_BUFFER_SIZE |
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SND_PCM_HW_PARBIT_BUFFER_TIME |
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SND_PCM_HW_PARBIT_TICK_TIME);
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for (i = 0; i < SND_PCM_EXTPLUG_HW_PARAMS; i++) {
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if (params[i].active)
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links &= ~excl_parbits[i];
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}
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return links;
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}
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static int snd_pcm_extplug_hw_refine_schange(snd_pcm_t *pcm,
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snd_pcm_hw_params_t *params,
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snd_pcm_hw_params_t *sparams)
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{
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extplug_priv_t *ext = pcm->private_data;
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unsigned int links = get_links(ext->sparams);
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return _snd_pcm_hw_params_refine(sparams, links, params);
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}
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static int snd_pcm_extplug_hw_refine_cchange(snd_pcm_t *pcm,
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snd_pcm_hw_params_t *params,
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snd_pcm_hw_params_t *sparams)
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{
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extplug_priv_t *ext = pcm->private_data;
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unsigned int links = get_links(ext->params);
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return _snd_pcm_hw_params_refine(params, links, sparams);
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}
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static int snd_pcm_extplug_hw_refine(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
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{
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int err = snd_pcm_hw_refine_slave(pcm, params,
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snd_pcm_extplug_hw_refine_cprepare,
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snd_pcm_extplug_hw_refine_cchange,
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snd_pcm_extplug_hw_refine_sprepare,
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snd_pcm_extplug_hw_refine_schange,
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snd_pcm_generic_hw_refine);
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return err;
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}
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/*
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* hw_params callback
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*/
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static int snd_pcm_extplug_hw_params(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
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{
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extplug_priv_t *ext = pcm->private_data;
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snd_pcm_t *slave = ext->plug.gen.slave;
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int err = snd_pcm_hw_params_slave(pcm, params,
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snd_pcm_extplug_hw_refine_cchange,
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snd_pcm_extplug_hw_refine_sprepare,
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snd_pcm_extplug_hw_refine_schange,
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snd_pcm_generic_hw_params);
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if (err < 0)
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return err;
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ext->data->slave_format = slave->format;
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ext->data->slave_subformat = slave->subformat;
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ext->data->slave_channels = slave->channels;
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ext->data->rate = slave->rate;
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INTERNAL(snd_pcm_hw_params_get_format)(params, &ext->data->format);
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INTERNAL(snd_pcm_hw_params_get_subformat)(params, &ext->data->subformat);
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INTERNAL(snd_pcm_hw_params_get_channels)(params, &ext->data->channels);
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if (ext->data->callback->hw_params) {
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err = ext->data->callback->hw_params(ext->data, params);
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if (err < 0)
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return err;
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}
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return 0;
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}
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/*
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* hw_free callback
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*/
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static int snd_pcm_extplug_hw_free(snd_pcm_t *pcm)
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{
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extplug_priv_t *ext = pcm->private_data;
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snd_pcm_hw_free(ext->plug.gen.slave);
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if (ext->data->callback->hw_free)
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return ext->data->callback->hw_free(ext->data);
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return 0;
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}
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/*
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* write_areas skeleton - call transfer callback
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*/
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static snd_pcm_uframes_t
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snd_pcm_extplug_write_areas(snd_pcm_t *pcm,
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const snd_pcm_channel_area_t *areas,
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snd_pcm_uframes_t offset,
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snd_pcm_uframes_t size,
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const snd_pcm_channel_area_t *slave_areas,
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snd_pcm_uframes_t slave_offset,
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snd_pcm_uframes_t *slave_sizep)
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{
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extplug_priv_t *ext = pcm->private_data;
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if (size > *slave_sizep)
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size = *slave_sizep;
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size = ext->data->callback->transfer(ext->data, slave_areas, slave_offset,
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areas, offset, size);
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*slave_sizep = size;
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return size;
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}
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/*
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* read_areas skeleton - call transfer callback
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*/
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static snd_pcm_uframes_t
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snd_pcm_extplug_read_areas(snd_pcm_t *pcm,
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const snd_pcm_channel_area_t *areas,
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snd_pcm_uframes_t offset,
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snd_pcm_uframes_t size,
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const snd_pcm_channel_area_t *slave_areas,
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snd_pcm_uframes_t slave_offset,
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snd_pcm_uframes_t *slave_sizep)
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{
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extplug_priv_t *ext = pcm->private_data;
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if (size > *slave_sizep)
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size = *slave_sizep;
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size = ext->data->callback->transfer(ext->data, areas, offset,
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slave_areas, slave_offset, size);
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*slave_sizep = size;
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return size;
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}
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/*
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* call init callback
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*/
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static int snd_pcm_extplug_init(snd_pcm_t *pcm)
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{
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extplug_priv_t *ext = pcm->private_data;
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return ext->data->callback->init(ext->data);
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}
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/*
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* dump setup
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*/
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static void snd_pcm_extplug_dump(snd_pcm_t *pcm, snd_output_t *out)
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{
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extplug_priv_t *ext = pcm->private_data;
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if (ext->data->callback->dump)
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ext->data->callback->dump(ext->data, out);
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else {
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if (ext->data->name)
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snd_output_printf(out, "%s\n", ext->data->name);
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else
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snd_output_printf(out, "External PCM Plugin\n");
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if (pcm->setup) {
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snd_output_printf(out, "Its setup is:\n");
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snd_pcm_dump_setup(pcm, out);
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}
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}
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snd_output_printf(out, "Slave: ");
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snd_pcm_dump(ext->plug.gen.slave, out);
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}
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static void clear_ext_params(extplug_priv_t *ext)
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{
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int i;
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for (i = 0; i < SND_PCM_EXTPLUG_HW_PARAMS; i++) {
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snd_ext_parm_clear(&ext->params[i]);
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snd_ext_parm_clear(&ext->sparams[i]);
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}
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}
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static int snd_pcm_extplug_close(snd_pcm_t *pcm)
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{
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extplug_priv_t *ext = pcm->private_data;
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snd_pcm_close(ext->plug.gen.slave);
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clear_ext_params(ext);
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if (ext->data->callback->close)
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ext->data->callback->close(ext->data);
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free(ext);
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return 0;
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}
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static const snd_pcm_ops_t snd_pcm_extplug_ops = {
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.close = snd_pcm_extplug_close,
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.info = snd_pcm_generic_info,
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.hw_refine = snd_pcm_extplug_hw_refine,
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.hw_params = snd_pcm_extplug_hw_params,
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.hw_free = snd_pcm_extplug_hw_free,
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.sw_params = snd_pcm_generic_sw_params,
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.channel_info = snd_pcm_generic_channel_info,
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.dump = snd_pcm_extplug_dump,
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.nonblock = snd_pcm_generic_nonblock,
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.async = snd_pcm_generic_async,
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.mmap = snd_pcm_generic_mmap,
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.munmap = snd_pcm_generic_munmap,
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};
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#endif /* !DOC_HIDDEN */
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/*
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* Exported functions
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*/
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/*! \page pcm_external_plugins PCM External Plugin SDK
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\section pcm_externals External Plugins
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The external plugins are implemented in a shared object file located
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at /usr/lib/alsa-lib (the exact location depends on the build option
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and asoundrc configuration). It has to be the file like
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libasound_module_pcm_MYPLUGIN.so, where MYPLUGIN corresponds to your
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own plugin name.
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The entry point of the plugin is defined via
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#SND_PCM_PLUGIN_DEFINE_FUNC() macro. This macro defines the function
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with a proper name to be referred from alsa-lib. The function takes
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the following 6 arguments:
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\code
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int (snd_pcm_t **pcmp, const char *name, snd_config_t *root,
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snd_config_t *conf, snd_pcm_stream_t stream, int mode)
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\endcode
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The first argument, pcmp, is the pointer to store the resultant PCM
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handle. The arguments name, root, stream and mode are the parameters
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to be passed to the plugin constructor. The conf is the configuration
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tree for the plugin. The arguments above are defined in the macro
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itself, so don't use variables with the same names to shadow
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parameters.
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After parsing the configuration parameters in the given conf tree,
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usually you will call the external plugin API function,
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#snd_pcm_extplug_create() or #snd_pcm_ioplug_create(), depending
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|
on the plugin type. The PCM handle must be filled *pcmp in return.
|
|
Then this function must return either a value 0 when succeeded, or a
|
|
negative value as the error code.
|
|
|
|
Finally, add #SND_PCM_PLUGIN_SYMBOL() with the name of your
|
|
plugin as the argument at the end. This defines the proper versioned
|
|
symbol as the reference.
|
|
|
|
The typical code would look like below:
|
|
\code
|
|
struct myplug_info {
|
|
snd_pcm_extplug_t ext;
|
|
int my_own_data;
|
|
...
|
|
};
|
|
|
|
SND_PCM_PLUGIN_DEFINE_FUNC(myplug)
|
|
{
|
|
snd_config_iterator_t i, next;
|
|
snd_config_t *slave = NULL;
|
|
struct myplug_info *myplug;
|
|
int err;
|
|
|
|
snd_config_for_each(i, next, conf) {
|
|
snd_config_t *n = snd_config_iterator_entry(i);
|
|
const char *id;
|
|
if (snd_config_get_id(n, &id) < 0)
|
|
continue;
|
|
if (strcmp(id, "comment") == 0 || strcmp(id, "type") == 0)
|
|
continue;
|
|
if (strcmp(id, "slave") == 0) {
|
|
slave = n;
|
|
continue;
|
|
}
|
|
if (strcmp(id, "my_own_parameter") == 0) {
|
|
....
|
|
continue;
|
|
}
|
|
SNDERR("Unknown field %s", id);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (! slave) {
|
|
SNDERR("No slave defined for myplug");
|
|
return -EINVAL;
|
|
}
|
|
|
|
myplug = calloc(1, sizeof(*myplug));
|
|
if (myplug == NULL)
|
|
return -ENOMEM;
|
|
|
|
myplug->ext.version = SND_PCM_EXTPLUG_VERSION;
|
|
myplug->ext.name = "My Own Plugin";
|
|
myplug->ext.callback = &my_own_callback;
|
|
myplug->ext.private_data = myplug;
|
|
....
|
|
|
|
err = snd_pcm_extplug_create(&myplug->ext, name, root, conf, stream, mode);
|
|
if (err < 0) {
|
|
myplug_free(myplug);
|
|
return err;
|
|
}
|
|
|
|
*pcmp = myplug->ext.pcm;
|
|
return 0;
|
|
}
|
|
|
|
SND_PCM_PLUGIN_SYMBOL(myplug);
|
|
\endcode
|
|
|
|
Read the codes in alsa-plugins package for the real examples.
|
|
|
|
|
|
\section pcm_extplug External Plugin: Filter-Type Plugin
|
|
|
|
The filter-type plugin is a plugin to convert the PCM signals from the input
|
|
and feeds to the output. Thus, this plugin always needs a slave PCM as its output.
|
|
|
|
The plugin can modify the format and the channels of the input/output PCM.
|
|
It can <i>not</i> modify the sample rate (because of simplicity reason).
|
|
|
|
The following fields have to be filled in extplug record before calling
|
|
#snd_pcm_extplug_create() : version, name, callback.
|
|
Otherfields are optional and should be initialized with zero.
|
|
|
|
The constant #SND_PCM_EXTPLUG_VERSION must be passed to the version
|
|
field for the version check in alsa-lib. A non-NULL ASCII string
|
|
has to be passed to the name field. The callback field contains the
|
|
table of callback functions for this plugin (defined as
|
|
#snd_pcm_extplug_callback_t).
|
|
|
|
The driver can set an arbitrary value (pointer) to private_data
|
|
field to refer its own data in the callbacks.
|
|
|
|
The rest fields are filled by #snd_pcm_extplug_create(). The pcm field
|
|
is the resultant PCM handle. The others are the current status of the
|
|
PCM.
|
|
|
|
The callback functions in #snd_pcm_extplug_callback_t define the real
|
|
behavior of the driver.
|
|
At least, transfer callback must be given. This callback is called
|
|
at each time certain size of data block is transfered to the slave
|
|
PCM. Other callbacks are optional.
|
|
|
|
The close callback is called when the PCM is closed. If the plugin
|
|
allocates private resources, this is the place to release them
|
|
again. The hw_params and hw_free callbacks are called at
|
|
#snd_pcm_hw_params() and #snd_pcm_hw_free() API calls,
|
|
respectively. The last, dump callback, is called for printing the
|
|
information of the given plugin.
|
|
|
|
The init callback is called when the PCM is at prepare state or any
|
|
initialization is issued. Use this callback to reset the PCM instance
|
|
to a sane initial state.
|
|
|
|
The hw_params constraints can be defined via either
|
|
#snd_pcm_extplug_set_param_minmax() and #snd_pcm_extplug_set_param_list()
|
|
functions after calling #snd_pcm_extplug_create().
|
|
The former defines the minimal and maximal acceptable values for the
|
|
given hw_params parameter (SND_PCM_EXTPLUG_HW_XXX).
|
|
This function can't be used for the format parameter. The latter
|
|
function specifies the available parameter values as the list.
|
|
As mentioned above, the rate can't be changed. Only changeable
|
|
parameters are sample format and channels.
|
|
|
|
To define the constraints of the slave PCM configuration, use
|
|
either #snd_pcm_extplug_set_slave_param_minmax() and
|
|
#snd_pcm_extplug_set_slave_param_list(). The arguments are as same
|
|
as former functions.
|
|
|
|
To clear the parameter constraints, call #snd_pcm_extplug_params_reset()
|
|
function.
|
|
|
|
*/
|
|
|
|
/**
|
|
* \brief Create an extplug instance
|
|
* \param extplug the extplug handle
|
|
* \param name name of the PCM
|
|
* \param root configuration tree root
|
|
* \param slave_conf slave configuration root
|
|
* \param stream stream direction
|
|
* \param mode PCM open mode
|
|
* \return 0 if successful, or a negative error code
|
|
*
|
|
* Creates the extplug instance based on the given handle.
|
|
* The slave_conf argument is mandatory, and usually taken from the config tree of the
|
|
* PCM plugin as "slave" config value.
|
|
* name, root, stream and mode arguments are the values used for opening the PCM.
|
|
*
|
|
* The callback is the mandatory field of extplug handle. At least, start, stop and
|
|
* pointer callbacks must be set before calling this function.
|
|
*/
|
|
int snd_pcm_extplug_create(snd_pcm_extplug_t *extplug, const char *name,
|
|
snd_config_t *root, snd_config_t *slave_conf,
|
|
snd_pcm_stream_t stream, int mode)
|
|
{
|
|
extplug_priv_t *ext;
|
|
int err;
|
|
snd_pcm_t *spcm, *pcm;
|
|
snd_config_t *sconf;
|
|
|
|
assert(root);
|
|
assert(extplug && extplug->callback);
|
|
assert(extplug->callback->transfer);
|
|
assert(slave_conf);
|
|
|
|
if (extplug->version != SND_PCM_EXTPLUG_VERSION) {
|
|
SNDERR("extplug: Plugin version mismatch\n");
|
|
return -ENXIO;
|
|
}
|
|
|
|
err = snd_pcm_slave_conf(root, slave_conf, &sconf, 0);
|
|
if (err < 0)
|
|
return err;
|
|
err = snd_pcm_open_slave(&spcm, root, sconf, stream, mode, NULL);
|
|
snd_config_delete(sconf);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
ext = calloc(1, sizeof(*ext));
|
|
if (! ext)
|
|
return -ENOMEM;
|
|
|
|
ext->data = extplug;
|
|
extplug->stream = stream;
|
|
|
|
snd_pcm_plugin_init(&ext->plug);
|
|
ext->plug.read = snd_pcm_extplug_read_areas;
|
|
ext->plug.write = snd_pcm_extplug_write_areas;
|
|
ext->plug.undo_read = snd_pcm_plugin_undo_read_generic;
|
|
ext->plug.undo_write = snd_pcm_plugin_undo_write_generic;
|
|
ext->plug.gen.slave = spcm;
|
|
ext->plug.gen.close_slave = 1;
|
|
if (extplug->callback->init)
|
|
ext->plug.init = snd_pcm_extplug_init;
|
|
|
|
err = snd_pcm_new(&pcm, SND_PCM_TYPE_EXTPLUG, name, stream, mode);
|
|
if (err < 0) {
|
|
free(ext);
|
|
return err;
|
|
}
|
|
|
|
extplug->pcm = pcm;
|
|
pcm->ops = &snd_pcm_extplug_ops;
|
|
pcm->fast_ops = &snd_pcm_plugin_fast_ops;
|
|
pcm->private_data = ext;
|
|
pcm->poll_fd = spcm->poll_fd;
|
|
pcm->poll_events = spcm->poll_events;
|
|
snd_pcm_set_hw_ptr(pcm, &ext->plug.hw_ptr, -1, 0);
|
|
snd_pcm_set_appl_ptr(pcm, &ext->plug.appl_ptr, -1, 0);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* \brief Delete the extplug instance
|
|
* \param extplug the extplug handle to delete
|
|
* \return 0 if successful, or a negative error code
|
|
*
|
|
* The destructor of extplug instance.
|
|
* Closes the PCM and deletes the associated resources.
|
|
*/
|
|
int snd_pcm_extplug_delete(snd_pcm_extplug_t *extplug)
|
|
{
|
|
return snd_pcm_close(extplug->pcm);
|
|
}
|
|
|
|
|
|
/**
|
|
* \brief Reset extplug parameters
|
|
* \param extplug the extplug handle
|
|
*
|
|
* Resets the all parameters for the given extplug handle.
|
|
*/
|
|
void snd_pcm_extplug_params_reset(snd_pcm_extplug_t *extplug)
|
|
{
|
|
extplug_priv_t *ext = extplug->pcm->private_data;
|
|
clear_ext_params(ext);
|
|
}
|
|
|
|
/**
|
|
* \brief Set slave parameter as the list
|
|
* \param extplug the extplug handle
|
|
* \param type parameter type
|
|
* \param num_list number of available values
|
|
* \param list the list of available values
|
|
* \return 0 if successful, or a negative error code
|
|
*
|
|
* Sets the slave parameter as the list.
|
|
* The available values of the given parameter type of the slave PCM is restricted
|
|
* to the ones of the given list.
|
|
*/
|
|
int snd_pcm_extplug_set_slave_param_list(snd_pcm_extplug_t *extplug, int type, unsigned int num_list, const unsigned int *list)
|
|
{
|
|
extplug_priv_t *ext = extplug->pcm->private_data;
|
|
if (type < 0 && type >= SND_PCM_EXTPLUG_HW_PARAMS) {
|
|
SNDERR("EXTPLUG: invalid parameter type %d", type);
|
|
return -EINVAL;
|
|
}
|
|
return snd_ext_parm_set_list(&ext->sparams[type], num_list, list);
|
|
}
|
|
|
|
/**
|
|
* \brief Set slave parameter as the min/max values
|
|
* \param extplug the extplug handle
|
|
* \param type parameter type
|
|
* \param min the minimum value
|
|
* \param max the maximum value
|
|
* \return 0 if successful, or a negative error code
|
|
*
|
|
* Sets the slave parameter as the min/max values.
|
|
* The available values of the given parameter type of the slave PCM is restricted
|
|
* between the given minimum and maximum values.
|
|
*/
|
|
int snd_pcm_extplug_set_slave_param_minmax(snd_pcm_extplug_t *extplug, int type, unsigned int min, unsigned int max)
|
|
{
|
|
extplug_priv_t *ext = extplug->pcm->private_data;
|
|
if (type < 0 && type >= SND_PCM_EXTPLUG_HW_PARAMS) {
|
|
SNDERR("EXTPLUG: invalid parameter type %d", type);
|
|
return -EINVAL;
|
|
}
|
|
if (is_mask_type(type)) {
|
|
SNDERR("EXTPLUG: invalid parameter type %d", type);
|
|
return -EINVAL;
|
|
}
|
|
return snd_ext_parm_set_minmax(&ext->sparams[type], min, max);
|
|
}
|
|
|
|
/**
|
|
* \brief Set master parameter as the list
|
|
* \param extplug the extplug handle
|
|
* \param type parameter type
|
|
* \param num_list number of available values
|
|
* \param list the list of available values
|
|
* \return 0 if successful, or a negative error code
|
|
*
|
|
* Sets the master parameter as the list.
|
|
* The available values of the given parameter type of this PCM (as input) is restricted
|
|
* to the ones of the given list.
|
|
*/
|
|
int snd_pcm_extplug_set_param_list(snd_pcm_extplug_t *extplug, int type, unsigned int num_list, const unsigned int *list)
|
|
{
|
|
extplug_priv_t *ext = extplug->pcm->private_data;
|
|
if (type < 0 && type >= SND_PCM_EXTPLUG_HW_PARAMS) {
|
|
SNDERR("EXTPLUG: invalid parameter type %d", type);
|
|
return -EINVAL;
|
|
}
|
|
return snd_ext_parm_set_list(&ext->params[type], num_list, list);
|
|
}
|
|
|
|
/**
|
|
* \brief Set master parameter as the min/max values
|
|
* \param extplug the extplug handle
|
|
* \param type parameter type
|
|
* \param min the minimum value
|
|
* \param max the maximum value
|
|
* \return 0 if successful, or a negative error code
|
|
*
|
|
* Sets the master parameter as the min/max values.
|
|
* The available values of the given parameter type of this PCM (as input) is restricted
|
|
* between the given minimum and maximum values.
|
|
*/
|
|
int snd_pcm_extplug_set_param_minmax(snd_pcm_extplug_t *extplug, int type, unsigned int min, unsigned int max)
|
|
{
|
|
extplug_priv_t *ext = extplug->pcm->private_data;
|
|
if (type < 0 && type >= SND_PCM_EXTPLUG_HW_PARAMS) {
|
|
SNDERR("EXTPLUG: invalid parameter type %d", type);
|
|
return -EINVAL;
|
|
}
|
|
if (is_mask_type(type)) {
|
|
SNDERR("EXTPLUG: invalid parameter type %d", type);
|
|
return -EINVAL;
|
|
}
|
|
return snd_ext_parm_set_minmax(&ext->params[type], min, max);
|
|
}
|
|
|