alsa-configuration.txt

linux 内核源代码

		Advanced Linux Sound Architecture - Driver
		==========================================
			    Configuration guide


Kernel Configuration
====================

To enable ALSA support you need at least to build the kernel with
primary sound card support (CONFIG_SOUND).  Since ALSA can emulate OSS,
you don't have to choose any of the OSS modules.

Enable "OSS API emulation" (CONFIG_SND_OSSEMUL) and both OSS mixer and
PCM supports if you want to run OSS applications with ALSA.

If you want to support the WaveTable functionality on cards such as
SB Live! then you need to enable "Sequencer support"
(CONFIG_SND_SEQUENCER).

To make ALSA debug messages more verbose, enable the "Verbose printk"
and "Debug" options.  To check for memory leaks, turn on "Debug memory"
too.  "Debug detection" will add checks for the detection of cards.

Please note that all the ALSA ISA drivers support the Linux isapnp API
(if the card supports ISA PnP).  You don't need to configure the cards
using isapnptools.


Creating ALSA devices
=====================

This depends on your distribution, but normally you use the /dev/MAKEDEV
script to create the necessary device nodes.  On some systems you use a
script named 'snddevices'.


Module parameters
=================

The user can load modules with options. If the module supports more than
one card and you have more than one card of the same type then you can
specify multiple values for the option separated by commas.

Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.

  Module snd
  ----------

    The core ALSA module.  It is used by all ALSA card drivers.
    It takes the following options which have global effects.

    major	- major number for sound driver
		- Default: 116
    cards_limit
		- limiting card index for auto-loading (1-8)
		- Default: 1
		- For auto-loading more than one card, specify this
		  option together with snd-card-X aliases.

  
  Module snd-pcm-oss
  ------------------

    The PCM OSS emulation module.
    This module takes options which change the mapping of devices.

    dsp_map	- PCM device number maps assigned to the 1st OSS device.
		- Default: 0
    adsp_map	- PCM device number maps assigned to the 2st OSS device.
		- Default: 1
    nonblock_open
		- Don't block opening busy PCM devices.  Default: 1

    For example, when dsp_map=2, /dev/dsp will be mapped to PCM #2 of
    the card #0.  Similarly, when adsp_map=0, /dev/adsp will be mapped
    to PCM #0 of the card #0.
    For changing the second or later card, specify the option with
    commas, such like "dsp_map=0,1".

    nonblock_open option is used to change the behavior of the PCM
    regarding opening the device.  When this option is non-zero,
    opening a busy OSS PCM device won't be blocked but return
    immediately with EAGAIN (just like O_NONBLOCK flag).
    
  Module snd-rawmidi
  ------------------

    This module takes options which change the mapping of devices.
    similar to those of the snd-pcm-oss module.

    midi_map	- MIDI device number maps assigned to the 1st OSS device.
		- Default: 0
    amidi_map	- MIDI device number maps assigned to the 2st OSS device.
		- Default: 1

  Common parameters for top sound card modules
  --------------------------------------------

    Each of top level sound card module takes the following options.

    index	- index (slot #) of sound card
		- Values: 0 through 31 or negative
		- If nonnegative, assign that index number
                - if negative, interpret as a bitmask of permissible
		  indices; the first free permitted index is assigned
		- Default: -1
    id		- card ID (identifier or name)
		- Can be up to 15 characters long
		- Default: the card type
		- A directory by this name is created under /proc/asound/
		  containing information about the card
		- This ID can be used instead of the index number in
		  identifying the card
    enable  	- enable card
		- Default: enabled, for PCI and ISA PnP cards

  Module snd-adlib
  ----------------

    Module for AdLib FM cards.

    port	- port # for OPL chip

    This module supports multiple cards. It does not support autoprobe, so
    the port must be specified. For actual AdLib FM cards it will be 0x388.
    Note that this card does not have PCM support and no mixer; only FM
    synthesis.

    Make sure you have "sbiload" from the alsa-tools package available and,
    after loading the module, find out the assigned ALSA sequencer port
    number through "sbiload -l". Example output:

      Port     Client name                       Port name
      64:0     OPL2 FM synth                     OPL2 FM Port

    Load the std.sb and drums.sb patches also supplied by sbiload:

      sbiload -p 64:0 std.sb drums.sb

    If you use this driver to drive an OPL3, you can use std.o3 and drums.o3
    instead. To have the card produce sound, use aplaymidi from alsa-utils:

      aplaymidi -p 64:0 foo.mid

  Module snd-ad1816a
  ------------------

    Module for sound cards based on Analog Devices AD1816A/AD1815 ISA chips.

    port	- port # for AD1816A chip (PnP setup)
    mpu_port	- port # for MPU-401 UART (PnP setup)
    fm_port	- port # for OPL3 (PnP setup)
    irq		- IRQ # for AD1816A chip (PnP setup)
    mpu_irq	- IRQ # for MPU-401 UART (PnP setup)
    dma1	- first DMA # for AD1816A chip (PnP setup)
    dma2	- second DMA # for AD1816A chip (PnP setup)
    clockfreq   - Clock frequency for AD1816A chip (default = 0, 33000Hz)
    
    This module supports multiple cards, autoprobe and PnP.
    
  Module snd-ad1848
  -----------------

    Module for sound cards based on AD1848/AD1847/CS4248 ISA chips.

    port	- port # for AD1848 chip
    irq		- IRQ # for AD1848  chip
    dma1	- DMA # for AD1848 chip (0,1,3)
    
    This module supports multiple cards.  It does not support autoprobe
    thus main port must be specified!!! Other ports are optional.
    
    The power-management is supported.

  Module snd-ad1889
  -----------------

    Module for Analog Devices AD1889 chips.

    ac97_quirk  - AC'97 workaround for strange hardware
                  See the description of intel8x0 module for details.

    This module supports multiple cards.

  Module snd-ali5451
  ------------------

    Module for ALi M5451 PCI chip.

    pcm_channels    - Number of hardware channels assigned for PCM
    spdif           - Support SPDIF I/O
    		    - Default: disabled

    This module supports one chip and autoprobe.

    The power-management is supported.

  Module snd-als100
  -----------------

    Module for sound cards based on Avance Logic ALS100/ALS120 ISA chips.

    port	- port # for ALS100 (SB16) chip (PnP setup)
    irq		- IRQ # for ALS100 (SB16) chip (PnP setup)
    dma8	- 8-bit DMA # for ALS100 (SB16) chip (PnP setup)
    dma16	- 16-bit DMA # for ALS100 (SB16) chip (PnP setup)
    mpu_port	- port # for MPU-401 UART (PnP setup)
    mpu_irq	- IRQ # for MPU-401 (PnP setup)
    fm_port	- port # for OPL3 FM (PnP setup)
    
    This module supports multiple cards, autoprobe and PnP.

    The power-management is supported.

  Module snd-als300
  -----------------

    Module for  Avance Logic ALS300 and ALS300+

    This module supports multiple cards.

    The power-management is supported.

  Module snd-als4000
  ------------------

    Module for sound cards based on Avance Logic ALS4000 PCI chip.

    joystick_port - port # for legacy joystick support.
                    0 = disabled (default), 1 = auto-detect
    
    This module supports multiple cards, autoprobe and PnP.

    The power-management is supported.

  Module snd-atiixp
  -----------------

    Module for ATI IXP 150/200/250/400 AC97 controllers.

    ac97_clock		- AC'97 clock (default = 48000)
    ac97_quirk		- AC'97 workaround for strange hardware
			  See "AC97 Quirk Option" section below.
    ac97_codec		- Workaround to specify which AC'97 codec 
			  instead of probing.  If this works for you
			  file a bug with your `lspci -vn` output.
			  -2  -- Force probing.
			  -1  -- Default behavior.
			  0-2 -- Use the specified codec.
    spdif_aclink	- S/PDIF transfer over AC-link (default = 1)

    This module supports one card and autoprobe.

    ATI IXP has two different methods to control SPDIF output.  One is
    over AC-link and another is over the "direct" SPDIF output.  The
    implementation depends on the motherboard, and you'll need to
    choose the correct one via spdif_aclink module option.

    The power-management is supported.

  Module snd-atiixp-modem
  -----------------------

    Module for ATI IXP 150/200/250 AC97 modem controllers.

    This module supports one card and autoprobe.

    Note: The default index value of this module is -2, i.e. the first
          slot is excluded.

    The power-management is supported.

  Module snd-au8810, snd-au8820, snd-au8830
  -----------------------------------------

    Module for Aureal Vortex, Vortex2 and Advantage device.

    pcifix	- Control PCI workarounds
		  0 = Disable all workarounds
		  1 = Force the PCI latency of the Aureal card to 0xff
		  2 = Force the Extend PCI#2 Internal Master for Efficient
		      Handling of Dummy Requests on the VIA KT133 AGP Bridge
		  3 = Force both settings
		  255 = Autodetect what is required (default)

    This module supports all ADB PCM channels, ac97 mixer, SPDIF, hardware
    EQ, mpu401, gameport. A3D and wavetable support are still in development.
    Development and reverse engineering work is being coordinated at
    http://savannah.nongnu.org/projects/openvortex/
    SPDIF output has a copy of the AC97 codec output, unless you use the
    "spdif" pcm device, which allows raw data passthru.
    The hardware EQ hardware and SPDIF is only present in the Vortex2 and 
    Advantage.

    Note: Some ALSA mixer applications don't handle the SPDIF sample rate 
           control correctly. If you have problems regarding this, try
           another ALSA compliant mixer (alsamixer works).

  Module snd-azt2320
  ------------------

    Module for sound cards based on Aztech System AZT2320 ISA chip (PnP only).

    port	- port # for AZT2320 chip (PnP setup)
    wss_port	- port # for WSS (PnP setup)
    mpu_port	- port # for MPU-401 UART (PnP setup)
    fm_port	- FM port # for AZT2320 chip (PnP setup)
    irq		- IRQ # for AZT2320 (WSS) chip (PnP setup)
    mpu_irq	- IRQ # for MPU-401 UART (PnP setup)
    dma1	- 1st DMA # for AZT2320 (WSS) chip (PnP setup)
    dma2	- 2nd DMA # for AZT2320 (WSS) chip (PnP setup)
    
    This module supports multiple cards, PnP and autoprobe.
    
    The power-management is supported.

  Module snd-azt3328
  ------------------

    Module for sound cards based on Aztech AZF3328 PCI chip.

    joystick	- Enable joystick (default off)

    This module supports multiple cards.

  Module snd-bt87x
  ----------------

    Module for video cards based on Bt87x chips.

    digital_rate - Override the default digital rate (Hz)
    load_all	- Load the driver even if the card model isn't known

    This module supports multiple cards.

    Note: The default index value of this module is -2, i.e. the first
          slot is excluded.

  Module snd-ca0106
  -----------------

    Module for Creative Audigy LS and SB Live 24bit

    This module supports multiple cards.


  Module snd-cmi8330
  ------------------

    Module for sound cards based on C-Media CMI8330 ISA chips.

    wssport	- port # for CMI8330 chip (WSS)
    wssirq	- IRQ # for CMI8330 chip (WSS)
    wssdma	- first DMA # for CMI8330 chip (WSS)
    sbport	- port # for CMI8330 chip (SB16)
    sbirq	- IRQ # for CMI8330 chip (SB16)
    sbdma8	- 8bit DMA # for CMI8330 chip (SB16)
    sbdma16	- 16bit DMA # for CMI8330 chip (SB16)

    This module supports multiple cards and autoprobe.

    The power-management is supported.

  Module snd-cmipci
  -----------------

    Module for C-Media CMI8338/8738/8768/8770 PCI sound cards.

    mpu_port    - port address of MIDI interface (8338 only):
		  0x300,0x310,0x320,0x330 = legacy port,
		  0 = disable (default)
    fm_port     - port address of OPL-3 FM synthesizer (8x38 only):
		  0x388 = legacy port,
		  1 = integrated PCI port (default on 8738),
		  0 = disable
    soft_ac3    - Software-conversion of raw SPDIF packets (model 033 only)
                  (default = 1)
    joystick_port - Joystick port address (0 = disable, 1 = auto-detect)

    This module supports autoprobe and multiple cards.
    
    The power-management is supported.

  Module snd-cs4231
  -----------------

    Module for sound cards based on CS4231 ISA chips.

    port	- port # for CS4231 chip