* aout_alsa.c : Alsa functions library
*****************************************************************************
* Copyright (C) 2000 VideoLAN
+ * $Id: aout_alsa.c,v 1.16 2001/05/30 17:03:11 sam Exp $
*
- * Authors:
- * Henri Fallon <henri@videolan.org>
+ * Authors: Henri Fallon <henri@videolan.org> - Original Author
+ * Jeffrey Baker <jwbaker@acm.org> - Port to ALSA 1.0 API
*
* 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
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
*****************************************************************************/
+#define MODULE_NAME alsa
+#include "modules_inner.h"
+
/*****************************************************************************
* Preamble
*****************************************************************************/
#include <stdlib.h> /* calloc(), malloc(), free() */
#include <sys/asoundlib.h>
-#include <linux/asound.h>
#include "config.h"
#include "common.h" /* boolean_t, byte_t */
#include "threads.h"
#include "mtime.h"
-#include "plugins.h"
+#include "tests.h"
#include "audio_output.h" /* aout_thread_t */
#include "intf_msg.h" /* intf_DbgMsg(), intf_ErrMsg() */
#include "main.h"
-
-
+#include "modules.h"
+#include "modules_export.h"
typedef struct alsa_device_s
{
typedef struct aout_sys_s
{
- snd_pcm_t * p_alsa_handle;
- alsa_device_t s_alsa_device;
- alsa_card_t s_alsa_card;
- snd_pcm_channel_params_t s_alsa_channel_params;
- snd_pcm_format_t s_alsa_format;
+ snd_pcm_t * p_alsa_handle;
+ unsigned long buffer_time;
+ unsigned long period_time;
+ unsigned long chunk_size;
+ unsigned long buffer_size;
+ unsigned long rate;
+ unsigned int bytes_per_sample;
+ unsigned int samples_per_frame;
+ unsigned int bytes_per_frame;
} aout_sys_t;
-
/*****************************************************************************
- * aout_AlsaOpen : creates a handle and opens an alsa device
+ * aout_Probe: probes the audio device and return a score
+ *****************************************************************************
+ * This function tries to open the dps and returns a score to the plugin
+ * manager so that it can make its choice.
*****************************************************************************/
+static int aout_Probe( probedata_t *p_data )
+{
+ int i_open_return, i_close_return;
+ aout_sys_t local_sys;
+
+ /* Open device */
+ i_open_return = snd_pcm_open( &(local_sys.p_alsa_handle), "plug:0,0",
+ SND_PCM_STREAM_PLAYBACK, 0 );
+ if( i_open_return )
+ {
+ intf_ErrMsg( "Aout_alsa: error opening alsa device in aout_probe(%d)"
+ " : %s", i_open_return, snd_strerror( i_open_return ) );
+ intf_WarnMsg( 1, "Aout_alsa : module scored 0" );
+ return ( 0 );
+ }
-int aout_AlsaOpen( aout_thread_t *p_aout )
+ /* Close it */
+ i_close_return = snd_pcm_close( local_sys.p_alsa_handle );
+
+ if( i_close_return )
+ {
+ intf_ErrMsg( "Aout_alsa: error closing alsa device in aout_probe(%d)"
+ " : %s", i_close_return, snd_strerror( i_close_return ) );
+ intf_WarnMsg( 1, "Aout_alsa : module scored 0" );
+ return( 0 );
+ }
+
+ if( TestMethod( AOUT_METHOD_VAR, "alsa" ) )
+ {
+ intf_WarnMsg( 1, "Aout_alsa : module scored 999" );
+ return( 999 );
+ }
+
+ /* And return score */
+ return( 100 );
+}
+
+/*****************************************************************************
+ * aout_Open : creates a handle and opens an alsa device
+ *****************************************************************************
+ * This function opens an alsa device, through the alsa API
+ *****************************************************************************/
+static int aout_Open( aout_thread_t *p_aout )
{
int i_open_returns;
p_aout->p_sys = malloc( sizeof( aout_sys_t ) );
if( p_aout->p_sys == NULL )
{
- intf_ErrMsg("Alsa Plugin : Could not allocate memory\n");
- intf_ErrMsg("error: %s\n", strerror(ENOMEM) );
+ intf_ErrMsg( "Aout_alsa : Could not allocate memory : %s",
+ strerror(ENOMEM) );
return( 1 );
}
- /* Initialize */
- p_aout->p_sys->s_alsa_device.i_num = 0;
- p_aout->p_sys->s_alsa_card.i_num = 0;
- /* FIXME : why not other format ? */
- p_aout->i_format = AOUT_FMT_S16_LE;
- /* FIXME : why always 2 channels ?*/
- p_aout->i_channels = 2;
- p_aout->l_rate = main_GetIntVariable( AOUT_RATE_VAR, AOUT_RATE_DEFAULT );
-
+ p_aout->i_format = AOUT_FORMAT_DEFAULT;
+ p_aout->i_channels = 1 + main_GetIntVariable( AOUT_STEREO_VAR,
+ AOUT_STEREO_DEFAULT );
+ p_aout->l_rate = main_GetIntVariable( AOUT_RATE_VAR,
+ AOUT_RATE_DEFAULT );
+
/* Open device */
- if ( ( i_open_returns = snd_pcm_open( &(p_aout->p_sys->p_alsa_handle),
- p_aout->p_sys->s_alsa_card.i_num,
- p_aout->p_sys->s_alsa_device.i_num,
- SND_PCM_OPEN_PLAYBACK ) ) )
+ if( ( i_open_returns = snd_pcm_open(&(p_aout->p_sys->p_alsa_handle),
+ "plug:0,0",
+ SND_PCM_STREAM_PLAYBACK, 0) ) )
{
- intf_ErrMsg ( "Could not open alsa device; exit = %i\n",
- i_open_returns );
- intf_ErrMsg ( "This means : %s\n\n",snd_strerror(i_open_returns) );
- return ( 1 );
+ intf_ErrMsg( "Could not open alsa device; exit = %i",
+ i_open_returns );
+ intf_ErrMsg( "This means : %s", snd_strerror(i_open_returns) );
+ return( -1 );
}
- intf_DbgMsg("Alsa plugin : Alsa device successfully opened\n");
- return ( 0 );
+ intf_DbgMsg( "Aout_alsa : Alsa device successfully opened" );
+ return( 0 );
}
/*****************************************************************************
- * aout_AlsaSetFormat : sets the alsa output format
+ * aout_SetFormat : sets the alsa output format
+ *****************************************************************************
+ * This function prepares the device, sets the rate, format, the mode
+ * ( "play as soon as you have data" ), and buffer information.
*****************************************************************************/
-
-int aout_AlsaSetFormat ( aout_thread_t *p_aout )
+static int aout_SetFormat( aout_thread_t *p_aout )
{
- int i_set_param_returns;
- int i_prepare_playback_returns;
- int i_playback_go_returns;
-
- /* Fill with zeros */
- memset(&p_aout->p_sys->s_alsa_channel_params,0,
- sizeof(p_aout->p_sys->s_alsa_channel_params));
+ int i_rv;
+ int i_format;
- /* Fill the s_alsa_channel_params structure */
-
- /* Tranfer mode and direction*/
- p_aout->p_sys->s_alsa_channel_params.channel = SND_PCM_CHANNEL_PLAYBACK ;
- p_aout->p_sys->s_alsa_channel_params.mode = SND_PCM_MODE_STREAM;
-
- /* Format and rate */
- p_aout->p_sys->s_alsa_channel_params.format.interleave = 1;
- if ( p_aout->i_format == AOUT_FMT_S16_LE )
- p_aout->p_sys->s_alsa_channel_params.format.format =
- SND_PCM_SFMT_S16_LE;
- else
- p_aout->p_sys->s_alsa_channel_params.format.format =
- SND_PCM_SFMT_S16_BE;
- p_aout->p_sys->s_alsa_channel_params.format.rate = p_aout->l_rate;
- p_aout->p_sys->s_alsa_channel_params.format.voices = p_aout->i_channels ;
+ snd_pcm_hw_params_t *p_hw;
+ snd_pcm_sw_params_t *p_sw;
- /* When to start playing and when to stop */
- p_aout->p_sys->s_alsa_channel_params.start_mode = SND_PCM_START_DATA;
- p_aout->p_sys->s_alsa_channel_params.stop_mode = SND_PCM_STOP_STOP;
-
- /* Buffer information . I have chosen the stream mode here
- * instead of the block mode. I don't know whether i'm wrong
- * but it seemed more logical */
- /* TODO : find the best value to put here. Probably depending
- * on many parameters */
- p_aout->p_sys->s_alsa_channel_params.buf.stream.queue_size = 131072;
+ snd_pcm_hw_params_alloca(&p_hw);
+ snd_pcm_sw_params_alloca(&p_sw);
+
+ switch (p_aout->i_format) {
+ case AOUT_FMT_S16_LE:
+ i_format = SND_PCM_FORMAT_S16_LE;
+ p_aout->p_sys->bytes_per_sample = 2;
+ break;
+
+ default:
+ i_format = SND_PCM_FORMAT_S16_BE;
+ p_aout->p_sys->bytes_per_sample = 2;
+ break;
+ }
+
+ p_aout->p_sys->samples_per_frame = p_aout->i_channels;
+ p_aout->p_sys->bytes_per_frame = p_aout->p_sys->samples_per_frame *
+ p_aout->p_sys->bytes_per_sample;
+
+ i_rv = snd_pcm_hw_params_any( p_aout->p_sys->p_alsa_handle, p_hw );
+ if( i_rv < 0 )
+ {
+ intf_ErrMsg( "Aout_alsa: Unable to retrieve initial parameters." );
+ return( -1 );
+ }
- p_aout->p_sys->s_alsa_channel_params.buf.stream.fill = SND_PCM_FILL_NONE ;
- p_aout->p_sys->s_alsa_channel_params.buf.stream.max_fill = 0 ;
-
- /* Now we pass this to the driver */
- i_set_param_returns = snd_pcm_channel_params (
- p_aout->p_sys->p_alsa_handle,
- &(p_aout->p_sys->s_alsa_channel_params) );
+ i_rv = snd_pcm_hw_params_set_access( p_aout->p_sys->p_alsa_handle, p_hw,
+ SND_PCM_ACCESS_RW_INTERLEAVED );
+ if( i_rv < 0 )
+ {
+ intf_ErrMsg( "Aout_alsa: Unable to set interleaved stream format." );
+ return( -1 );
+ }
- if ( i_set_param_returns )
+ i_rv = snd_pcm_hw_params_set_format( p_aout->p_sys->p_alsa_handle,
+ p_hw, i_format );
+ if( i_rv < 0 )
{
- intf_ErrMsg ( "ALSA_PLUGIN : Unable to set parameters; exit = %i\n",
- i_set_param_returns );
- intf_ErrMsg( "This means : %s\n\n",
- snd_strerror( i_set_param_returns ) );
- return ( 1 );
+ intf_ErrMsg( "Aout_alsa: Unable to set stream sample size and word"
+ " order." );
+ return( -1 );
}
- /* we shall now prepare the channel */
- i_prepare_playback_returns =
- snd_pcm_playback_prepare ( p_aout->p_sys->p_alsa_handle );
-
- if ( i_prepare_playback_returns )
+ i_rv = snd_pcm_hw_params_set_channels( p_aout->p_sys->p_alsa_handle, p_hw,
+ p_aout->i_channels );
+ if( i_rv < 0 )
{
- intf_ErrMsg ( "ALSA_PLUGIN : Unable to prepare channel : exit = %i\n",
- i_prepare_playback_returns );
- intf_ErrMsg( "This means : %s\n\n",
- snd_strerror( i_set_param_returns ) );
-
- return ( 1 );
+ intf_ErrMsg( "Aout_alsa: Unable to set number of output channels." );
+ return( -1 );
}
- /* then we may go */
- i_playback_go_returns =
- snd_pcm_playback_go ( p_aout->p_sys->p_alsa_handle );
- if ( i_playback_go_returns )
+ i_rv = snd_pcm_hw_params_set_rate_near( p_aout->p_sys->p_alsa_handle, p_hw,
+ p_aout->l_rate, 0 );
+ if( i_rv < 0 )
{
- intf_ErrMsg ( "ALSA_PLUGIN : Unable to prepare channel (bis) :
- exit = %i\n", i_playback_go_returns );
- intf_ErrMsg( "This means : %s\n\n",
- snd_strerror( i_set_param_returns ) );
- return ( 1 );
+ intf_ErrMsg( "Aout_alsa: Unable to set sample rate." );
+ return( -1 );
}
- return ( 0 );
-}
+ else
+ p_aout->p_sys->rate = i_rv;
+
+ i_rv = snd_pcm_hw_params_set_buffer_time_near( p_aout->p_sys->p_alsa_handle,
+ p_hw, AOUT_BUFFER_DURATION,
+ 0 );
+ if( i_rv < 0 )
+ {
+ intf_ErrMsg( "Aout_alsa: Unable to set buffer time." );
+ return( -1 );
+ }
+ else
+ p_aout->p_sys->buffer_time = i_rv;
+
+ i_rv = snd_pcm_hw_params_set_period_time_near( p_aout->p_sys->p_alsa_handle,
+ p_hw, p_aout->p_sys->buffer_time / p_aout->p_sys->bytes_per_frame, 0 );
+ if( i_rv < 0 )
+ {
+ intf_ErrMsg( "Aout_alsa: Unable to set period time." );
+ return( -1 );
+ }
+ else
+ p_aout->p_sys->period_time = i_rv;
+
+ i_rv = snd_pcm_hw_params(p_aout->p_sys->p_alsa_handle, p_hw);
+ if (i_rv < 0)
+ {
+ intf_ErrMsg( "Aout_alsa: Unable to set hardware configuration." );
+ return( -1 );
+ }
+
+ p_aout->p_sys->chunk_size = snd_pcm_hw_params_get_period_size( p_hw, 0 );
+ p_aout->p_sys->buffer_size = snd_pcm_hw_params_get_buffer_size( p_hw );
+
+ snd_pcm_sw_params_current( p_aout->p_sys->p_alsa_handle, p_sw );
+ i_rv = snd_pcm_sw_params_set_sleep_min( p_aout->p_sys->p_alsa_handle, p_sw,
+ 0 );
+
+ i_rv = snd_pcm_sw_params_set_avail_min( p_aout->p_sys->p_alsa_handle, p_sw,
+ p_aout->p_sys->chunk_size );
+
+ /* Worked with the CVS version but not with 0.9beta3
+ i_rv = snd_pcm_sw_params_set_start_threshold( p_aout->p_sys->p_alsa_handle,
+ p_sw, p_aout->p_sys->buffer_size );
+
+ i_rv = snd_pcm_sw_params_set_stop_threshold( p_aout->p_sys->p_alsa_handle,
+ p_sw, p_aout->p_sys->buffer_size);
+ */
+ i_rv = snd_pcm_sw_params( p_aout->p_sys->p_alsa_handle, p_sw );
+ if( i_rv < 0 )
+ {
+ intf_ErrMsg( "Aout_alsa: Unable to set software configuration." );
+ return( -1 );
+ }
-/*****************************************************************************
- * aout_AlsaReset: resets the dsp
- *****************************************************************************/
-int aout_AlsaReset ( aout_thread_t *p_aout )
-{
- /* TODO : put something in here, such as close and open again
- * or check status, drain, flush, .... */
- return ( 0 );
-}
-/*****************************************************************************
- * aout_AlsaSetChannels: sets mono, stereo and other modes
- *****************************************************************************/
-int aout_AlsaSetChannels ( aout_thread_t *p_aout )
-{
- /* TODO : normally, nothing
- * everything should be done in the AlsaSetFormat, as far a I understand
- * the alsa documentation
- */
- return ( 0 );
+ return( 0 );
}
/*****************************************************************************
- * aout_AlsaSetRate: sets the audio output rate
+ * static void aout_HandleXrun : reprepare the output
*****************************************************************************
- * As in the previous function, the rate is supposed to be set in the
- * AlsaSetFormat function
+ * When buffer gets empty, the driver goes in "Xrun" state, where it needs
+ * to be reprepared before playing again
*****************************************************************************/
-int aout_AlsaSetRate ( aout_thread_t *p_aout )
+static void aout_HandleXrun(aout_thread_t *p_aout)
{
- return ( 0 );
+ int i_rv;
+
+ intf_ErrMsg( "Aout_alsa: resetting output after buffer underrun." );
+
+ i_rv = snd_pcm_reset( p_aout->p_sys->p_alsa_handle );
+ i_rv = snd_pcm_prepare( p_aout->p_sys->p_alsa_handle );
+ if( i_rv < 0 )
+ intf_ErrMsg( "Aout_alsa: Unable to recover from buffer underrun: %s",
+ snd_strerror( i_rv ) );
}
+
/*****************************************************************************
- * aout_AlsaGetBufInfo: buffer status query
+ * aout_BufInfo: buffer status query
+ *****************************************************************************
+ * This function returns the number of used byte in the queue.
+ * It also deals with errors : indeed if the device comes to run out
+ * of data to play, it switches to the "underrun" status. It has to
+ * be flushed and re-prepared
*****************************************************************************/
-long aout_AlsaGetBufInfo ( aout_thread_t *p_aout, long l_buffer_limit )
+static long aout_GetBufInfo( aout_thread_t *p_aout, long l_buffer_limit )
{
- snd_pcm_channel_status_t alsa_channel_status;
+ snd_pcm_status_t *p_status;
int i_alsa_get_status_returns;
- memset (&alsa_channel_status, 0, sizeof(alsa_channel_status));
-
- i_alsa_get_status_returns = snd_pcm_channel_status (
- p_aout->p_sys->p_alsa_handle, &alsa_channel_status );
+ snd_pcm_status_alloca( &p_status );
- if ( i_alsa_get_status_returns )
+ i_alsa_get_status_returns = snd_pcm_status( p_aout->p_sys->p_alsa_handle,
+ p_status );
+
+ if( i_alsa_get_status_returns )
{
- intf_ErrMsg ( "Error getting alsa buffer info; exit=%i\n",
- i_alsa_get_status_returns );
- intf_ErrMsg ( "This means : %s \n\n",
- snd_strerror ( i_alsa_get_status_returns ) );
- return ( 1 );
+ intf_ErrMsg ( "Aout_alsa: Error getting alsa buffer info (%d) : %s",
+ i_alsa_get_status_returns,
+ snd_strerror ( i_alsa_get_status_returns ) );
+ return ( -1 );
}
- switch (alsa_channel_status.status)
+ switch( snd_pcm_status_get_state( p_status ) )
{
- case SND_PCM_STATUS_NOTREADY : intf_ErrMsg("Status NOT READY \n \n");
- break;
- case SND_PCM_STATUS_UNDERRUN : {
- int i_prepare_returns;
- intf_ErrMsg(
- "Status UNDERRUN ... reseting queue \n \n");
- i_prepare_returns =
- snd_pcm_playback_prepare(
- p_aout->p_sys->p_alsa_handle );
- if ( i_prepare_returns )
- {
- intf_ErrMsg(
- "Error : could not flush : %i\n",
- i_prepare_returns);
- intf_ErrMsg(
- "This means : %s\n",
- snd_strerror(i_prepare_returns));
- }
- break;
- }
+ case SND_PCM_STATE_XRUN :
+ aout_HandleXrun( p_aout );
+ break;
+
+ case SND_PCM_STATE_OPEN:
+ case SND_PCM_STATE_PREPARED:
+ case SND_PCM_STATE_RUNNING:
+ break;
+
+ default:
+ intf_ErrMsg( "Aout_alsa: Encountered unhandled condition %i!",
+ snd_pcm_status_get_state( p_status ) );
+ break;
}
- return ( alsa_channel_status.count );
+
+ return( snd_pcm_status_get_avail(p_status) *
+ p_aout->p_sys->bytes_per_frame );
}
/*****************************************************************************
- * aout_AlsaPlaySamples
+ * aout_Play : plays a sample
+ *****************************************************************************
+ * Plays a sample using the snd_pcm_writei function from the alsa API
*****************************************************************************/
-void aout_AlsaPlaySamples ( aout_thread_t *p_aout, byte_t *buffer, int i_size )
+static void aout_Play( aout_thread_t *p_aout, byte_t *buffer, int i_size )
{
- int i_write_returns;
-
- i_write_returns = (int) snd_pcm_write (
- p_aout->p_sys->p_alsa_handle, (void *)buffer, (size_t) i_size );
-
- if ( i_write_returns <= 0 )
- {
- intf_ErrMsg ( "Error writing blocks; exit=%i\n", i_write_returns );
- intf_ErrMsg ( "This means : %s\n", snd_strerror( i_write_returns ) );
+ snd_pcm_uframes_t tot_frames;
+ snd_pcm_uframes_t frames_left;
+ snd_pcm_uframes_t rv;
+
+ tot_frames = i_size / p_aout->p_sys->bytes_per_frame;
+ frames_left = tot_frames;
+
+ while( frames_left > 0 )
+ {
+ rv = snd_pcm_writei( p_aout->p_sys->p_alsa_handle, buffer +
+ (tot_frames - frames_left) *
+ p_aout->p_sys->bytes_per_frame, frames_left );
+
+ if( (signed int) rv < 0 )
+ {
+ intf_ErrMsg( "Aout_alsa: error writing to output: %s",
+ snd_strerror( rv ) );
+ return;
+ }
+
+ frames_left -= rv;
}
}
/*****************************************************************************
- * aout_AlsaClose : close the Alsa device
+ * aout_Close : close the Alsa device
*****************************************************************************/
-void aout_AlsaClose ( aout_thread_t *p_aout )
+static void aout_Close( aout_thread_t *p_aout )
{
int i_close_returns;
- i_close_returns = snd_pcm_close ( p_aout->p_sys->p_alsa_handle );
+ i_close_returns = snd_pcm_close( p_aout->p_sys->p_alsa_handle );
- if ( i_close_returns )
+ if( i_close_returns )
{
- intf_ErrMsg( "Error closing alsa device; exit=%i\n",i_close_returns );
- intf_ErrMsg( "This means : %s\n\n",snd_strerror( i_close_returns ) );
+ intf_ErrMsg( "Aout_alsa: error closing alsa device (%d): %s",
+ i_close_returns, snd_strerror( i_close_returns ) );
}
- free(p_aout->p_sys);
+
+ free( p_aout->p_sys );
- intf_DbgMsg( "Alsa plugin : Alsa device closed\n");
+ intf_DbgMsg( "Aout_alsa : Alsa device closed" );
+}
+
+/*****************************************************************************
+ * Functions exported as capabilities. They are declared as static so that
+ * we don't pollute the namespace too much.
+ *****************************************************************************/
+void _M( aout_getfunctions )( function_list_t * p_function_list )
+{
+ p_function_list->pf_probe = aout_Probe;
+ p_function_list->functions.aout.pf_open = aout_Open;
+ p_function_list->functions.aout.pf_setformat = aout_SetFormat;
+ p_function_list->functions.aout.pf_getbufinfo = aout_GetBufInfo;
+ p_function_list->functions.aout.pf_play = aout_Play;
+ p_function_list->functions.aout.pf_close = aout_Close;
}