Alsa library has different version of read and driver interaction functions why?

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I was going through alsa library code, I wanted to know read function that is being used. However I see there are more than one version of read functions.
i.e

.readi = snd_pcm_hw_readi

.readi = snd_pcm_ioplug_readi

.readi = snd_pcm_mmap_readi

.readi = snd_pcm_dshare_readi

.readi = snd_pcm_plugin_readi

I am not sure how does alsa library choose which function to use ?

what params make it choose different API's (like swparams ,hwparams)

asked Nov 11 at 13:20

vishwanath patil

116

Those are from different plugins.
– CL.
Nov 11 at 14:46

alsa.conf is the only file decides what plugins we use ?
– vishwanath patil
Nov 12 at 6:20

You give a device name to snd_pcm_open(), and that name is looked up in the configuration files.
– CL.
Nov 12 at 7:23

one varitation that I saw was "snd_pcm_plugin_fast_ops" that was decided based on hw_params and requested params. in "snd_pcm_plug_insert_plugins" function
– vishwanath patil
Nov 13 at 3:56

add a comment |

up vote
0
down vote

favorite

I was going through alsa library code, I wanted to know read function that is being used. However I see there are more than one version of read functions.
i.e

.readi = snd_pcm_hw_readi

.readi = snd_pcm_ioplug_readi

.readi = snd_pcm_mmap_readi

.readi = snd_pcm_dshare_readi

.readi = snd_pcm_plugin_readi

I am not sure how does alsa library choose which function to use ?

what params make it choose different API's (like swparams ,hwparams)

asked Nov 11 at 13:20

vishwanath patil

116

Those are from different plugins.
– CL.
Nov 11 at 14:46

alsa.conf is the only file decides what plugins we use ?
– vishwanath patil
Nov 12 at 6:20

You give a device name to snd_pcm_open(), and that name is looked up in the configuration files.
– CL.
Nov 12 at 7:23

one varitation that I saw was "snd_pcm_plugin_fast_ops" that was decided based on hw_params and requested params. in "snd_pcm_plug_insert_plugins" function
– vishwanath patil
Nov 13 at 3:56

add a comment |

up vote
0
down vote

favorite

I was going through alsa library code, I wanted to know read function that is being used. However I see there are more than one version of read functions.
i.e

.readi = snd_pcm_hw_readi

.readi = snd_pcm_ioplug_readi

.readi = snd_pcm_mmap_readi

.readi = snd_pcm_dshare_readi

.readi = snd_pcm_plugin_readi

I am not sure how does alsa library choose which function to use ?

what params make it choose different API's (like swparams ,hwparams)

asked Nov 11 at 13:20

vishwanath patil

116

I was going through alsa library code, I wanted to know read function that is being used. However I see there are more than one version of read functions.
i.e

.readi = snd_pcm_hw_readi

.readi = snd_pcm_ioplug_readi

.readi = snd_pcm_mmap_readi

.readi = snd_pcm_dshare_readi

.readi = snd_pcm_plugin_readi

I am not sure how does alsa library choose which function to use ?

what params make it choose different API's (like swparams ,hwparams)

linux-kernel alsa libalsa

asked Nov 11 at 13:20

vishwanath patil

116

asked Nov 11 at 13:20

vishwanath patil

116

asked Nov 11 at 13:20

vishwanath patil

116

asked Nov 11 at 13:20

vishwanath patil

116

asked Nov 11 at 13:20

vishwanath patil

116

Those are from different plugins.
– CL.
Nov 11 at 14:46

alsa.conf is the only file decides what plugins we use ?
– vishwanath patil
Nov 12 at 6:20

You give a device name to snd_pcm_open(), and that name is looked up in the configuration files.
– CL.
Nov 12 at 7:23

one varitation that I saw was "snd_pcm_plugin_fast_ops" that was decided based on hw_params and requested params. in "snd_pcm_plug_insert_plugins" function
– vishwanath patil
Nov 13 at 3:56

add a comment |

Those are from different plugins.
– CL.
Nov 11 at 14:46

alsa.conf is the only file decides what plugins we use ?
– vishwanath patil
Nov 12 at 6:20

You give a device name to snd_pcm_open(), and that name is looked up in the configuration files.
– CL.
Nov 12 at 7:23

one varitation that I saw was "snd_pcm_plugin_fast_ops" that was decided based on hw_params and requested params. in "snd_pcm_plug_insert_plugins" function
– vishwanath patil
Nov 13 at 3:56

Those are from different plugins.
– CL.
Nov 11 at 14:46

alsa.conf is the only file decides what plugins we use ?
– vishwanath patil
Nov 12 at 6:20

You give a device name to snd_pcm_open(), and that name is looked up in the configuration files.
– CL.
Nov 12 at 7:23

one varitation that I saw was "snd_pcm_plugin_fast_ops" that was decided based on hw_params and requested params. in "snd_pcm_plug_insert_plugins" function
– vishwanath patil
Nov 13 at 3:56

add a comment |

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