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diff --git a/Documentation/sound/oss/Introduction b/Documentation/sound/oss/Introduction deleted file mode 100644 index 42da2d8fa372..000000000000 --- a/Documentation/sound/oss/Introduction +++ /dev/null @@ -1,459 +0,0 @@ -Introduction Notes on Modular Sound Drivers and Soundcore -Wade Hampton -2/14/2001 - -Purpose: -======== -This document provides some general notes on the modular -sound drivers and their configuration, along with the -support modules sound.o and soundcore.o. - -Note, some of this probably should be added to the Sound-HOWTO! - -Note, soundlow.o was present with 2.2 kernels but is not -required for 2.4.x kernels. References have been removed -to this. - - -Copying: -======== -none - - -History: -======== -0.1.0 11/20/1998 First version, draft -1.0.0 11/1998 Alan Cox changes, incorporation in 2.2.0 - as Documentation/sound/oss/Introduction -1.1.0 6/30/1999 Second version, added notes on making the drivers, - added info on multiple sound cards of similar types,] - added more diagnostics info, added info about esd. - added info on OSS and ALSA. -1.1.1 19991031 Added notes on sound-slot- and sound-service. - (Alan Cox) -1.1.2 20000920 Modified for Kernel 2.4 (Christoph Hellwig) -1.1.3 20010214 Minor notes and corrections (Wade Hampton) - Added examples of sound-slot-0, etc. - - -Modular Sound Drivers: -====================== - -Thanks to the GREAT work by Alan Cox (alan@lxorguk.ukuu.org.uk), - -[And Oleg Drokin, Thomas Sailer, Andrew Veliath and more than a few - others - not to mention Hannu's original code being designed well - enough to cope with that kind of chopping up](Alan) - -the standard Linux kernels support a modular sound driver. From -Alan's comments in linux/drivers/sound/README.FIRST: - - The modular sound driver patches were funded by Red Hat Software - (www.redhat.com). The sound driver here is thus a modified version of - Hannu's code. Please bear that in mind when considering the appropriate - forums for bug reporting. - -The modular sound drivers may be loaded via insmod or modprobe. -To support all the various sound modules, there are two general -support modules that must be loaded first: - - soundcore.o: Top level handler for the sound system, provides - a set of functions for registration of devices - by type. - - sound.o: Common sound functions required by all modules. - -For the specific sound modules (e.g., sb.o for the Soundblaster), -read the documentation on that module to determine what options -are available, for example IRQ, address, DMA. - -Warning, the options for different cards sometime use different names -for the same or a similar feature (dma1= versus dma16=). As a last -resort, inspect the code (search for module_param). - -Notes: - -1. There is a new OpenSource sound driver called ALSA which is - currently under development: http://www.alsa-project.org/ - The ALSA drivers support some newer hardware that may not - be supported by this sound driver and also provide some - additional features. - -2. The commercial OSS driver may be obtained from the site: - http://www.opensound.com. This may be used for cards that - are unsupported by the kernel driver, or may be used - by other operating systems. - -3. The enlightenment sound daemon may be used for playing - multiple sounds at the same time via a single card, eliminating - some of the requirements for multiple sound card systems. For - more information, see: http://www.tux.org/~ricdude/EsounD.html - The "esd" program may be used with the real-player and mpeg - players like mpg123 and x11amp. The newer real-player - and some games even include built-in support for ESD! - - -Building the Modules: -===================== - -This document does not provide full details on building the -kernel, etc. The notes below apply only to making the kernel -sound modules. If this conflicts with the kernel's README, -the README takes precedence. - -1. To make the kernel sound modules, cd to your /usr/src/linux - directory (typically) and type make config, make menuconfig, - or make xconfig (to start the command line, dialog, or x-based - configuration tool). - -2. Select the Sound option and a dialog will be displayed. - -3. Select M (module) for "Sound card support". - -4. Select your sound driver(s) as a module. For ProAudio, Sound - Blaster, etc., select M (module) for OSS sound modules. - [thanks to Marvin Stodolsky <stodolsk@erols.com>]A - -5. Make the kernel (e.g., make bzImage), and install the kernel. - -6. Make the modules and install them (make modules; make modules_install). - -Note, for 2.5.x kernels, make sure you have the newer module-init-tools -installed or modules will not be loaded properly. 2.5.x requires an -updated module-init-tools. - - -Plug and Play (PnP: -=================== - -If the sound card is an ISA PnP card, isapnp may be used -to configure the card. See the file isapnp.txt in the -directory one level up (e.g., /usr/src/linux/Documentation). - -Also the 2.4.x kernels provide PnP capabilities, see the -file NEWS in this directory. - -PCI sound cards are highly recommended, as they are far -easier to configure and from what I have read, they use -less resources and are more CPU efficient. - - -INSMOD: -======= - -If loading via insmod, the common modules must be loaded in the -order below BEFORE loading the other sound modules. The card-specific -modules may then be loaded (most require parameters). For example, -I use the following via a shell script to load my SoundBlaster: - -SB_BASE=0x240 -SB_IRQ=9 -SB_DMA=3 -SB_DMA2=5 -SB_MPU=0x300 -# -echo Starting sound -/sbin/insmod soundcore -/sbin/insmod sound -# -echo Starting sound blaster.... -/sbin/insmod uart401 -/sbin/insmod sb io=$SB_BASE irq=$SB_IRQ dma=$SB_DMA dma16=$SB_DMA2 mpu_io=$SB_MP - -When using sound as a module, I typically put these commands -in a file such as /root/soundon.sh. - - -MODPROBE: -========= - -If loading via modprobe, these common files are automatically loaded when -requested by modprobe. For example, my /etc/modprobe.d/oss.conf contains: - -alias sound sb -options sb io=0x240 irq=9 dma=3 dma16=5 mpu_io=0x300 - -All you need to do to load the module is: - - /sbin/modprobe sb - - -Sound Status: -============= - -The status of sound may be read/checked by: - cat (anyfile).au >/dev/audio - -[WWH: This may not work properly for SoundBlaster PCI 128 cards -such as the es1370/1 (see the es1370/1 files in this directory) -as they do not automatically support uLaw on /dev/audio.] - -The status of the modules and which modules depend on -which other modules may be checked by: - /sbin/lsmod - -/sbin/lsmod should show something like the following: - sb 26280 0 - uart401 5640 0 [sb] - sound 57112 0 [sb uart401] - soundcore 1968 8 [sb sound] - - -Removing Sound: -=============== - -Sound may be removed by using /sbin/rmmod in the reverse order -in which you load the modules. Note, if a program has a sound device -open (e.g., xmixer), that module (and the modules on which it -depends) may not be unloaded. - -For example, I use the following to remove my Soundblaster (rmmod -in the reverse order in which I loaded the modules): - -/sbin/rmmod sb -/sbin/rmmod uart401 -/sbin/rmmod sound -/sbin/rmmod soundcore - -When using sound as a module, I typically put these commands -in a script such as /root/soundoff.sh. - - -Removing Sound for use with OSS: -================================ - -If you get really stuck or have a card that the kernel modules -will not support, you can get a commercial sound driver from -http://www.opensound.com. Before loading the commercial sound -driver, you should do the following: - -1. remove sound modules (detailed above) -2. remove the sound modules from /etc/modprobe.d/*.conf -3. move the sound modules from /lib/modules/<kernel>/misc - (for example, I make a /lib/modules/<kernel>/misc/tmp - directory and copy the sound module files to that - directory). - - -Multiple Sound Cards: -===================== - -The sound drivers will support multiple sound cards and there -are some great applications like multitrack that support them. -Typically, you need two sound cards of different types. Note, this -uses more precious interrupts and DMA channels and sometimes -can be a configuration nightmare. I have heard reports of 3-4 -sound cards (typically I only use 2). You can sometimes use -multiple PCI sound cards of the same type. - -On my machine I have two sound cards (cs4232 and Soundblaster Vibra -16). By loading sound as modules, I can control which is the first -sound device (/dev/dsp, /dev/audio, /dev/mixer) and which is -the second. Normally, the cs4232 (Dell sound on the motherboard) -would be the first sound device, but I prefer the Soundblaster. -All you have to do is to load the one you want as /dev/dsp -first (in my case "sb") and then load the other one -(in my case "cs4232"). - -If you have two cards of the same type that are jumpered -cards or different PnP revisions, you may load the same -module twice. For example, I have a SoundBlaster vibra 16 -and an older SoundBlaster 16 (jumpers). To load the module -twice, you need to do the following: - -1. Copy the sound modules to a new name. For example - sb.o could be copied (or symlinked) to sb1.o for the - second SoundBlaster. - -2. Make a second entry in /etc/modprobe.d/*conf, for example, - sound1 or sb1. This second entry should refer to the - new module names for example sb1, and should include - the I/O, etc. for the second sound card. - -3. Update your soundon.sh script, etc. - -Warning: I have never been able to get two PnP sound cards of the -same type to load at the same time. I have tried this several times -with the Soundblaster Vibra 16 cards. OSS has indicated that this -is a PnP problem.... If anyone has any luck doing this, please -send me an E-MAIL. PCI sound cards should not have this problem.a -Since this was originally release, I have received a couple of -mails from people who have accomplished this! - -NOTE: In Linux 2.4 the Sound Blaster driver (and only this one yet) -supports multiple cards with one module by default. -Read the file 'Soundblaster' in this directory for details. - - -Sound Problems: -=============== - -First RTFM (including the troubleshooting section -in the Sound-HOWTO). - -1) If you are having problems loading the modules (for - example, if you get device conflict errors) try the - following: - - A) If you have Win95 or NT on the same computer, - write down what addresses, IRQ, and DMA channels - those were using for the same hardware. You probably - can use these addresses, IRQs, and DMA channels. - You should really do this BEFORE attempting to get - sound working! - - B) Check (cat) /proc/interrupts, /proc/ioports, - and /proc/dma. Are you trying to use an address, - IRQ or DMA port that another device is using? - - C) Check (cat) /proc/isapnp - - D) Inspect your /var/log/messages file. Often that will - indicate what IRQ or IO port could not be obtained. - - E) Try another port or IRQ. Note this may involve - using the PnP tools to move the sound card to - another location. Sometimes this is the only way - and it is more or less trial and error. - -2) If you get motor-boating (the same sound or part of a - sound clip repeated), you probably have either an IRQ - or DMA conflict. Move the card to another IRQ or DMA - port. This has happened to me when playing long files - when I had an IRQ conflict. - -3. If you get dropouts or pauses when playing high sample - rate files such as using mpg123 or x11amp/xmms, you may - have too slow of a CPU and may have to use the options to - play the files at 1/2 speed. For example, you may use - the -2 or -4 option on mpg123. You may also get this - when trying to play mpeg files stored on a CD-ROM - (my Toshiba T8000 PII/366 sometimes has this problem). - -4. If you get "cannot access device" errors, your /dev/dsp - files, etc. may be set to owner root, mode 600. You - may have to use the command: - chmod 666 /dev/dsp /dev/mixer /dev/audio - -5. If you get "device busy" errors, another program has the - sound device open. For example, if using the Enlightenment - sound daemon "esd", the "esd" program has the sound device. - If using "esd", please RTFM the docs on ESD. For example, - esddsp <program> may be used to play files via a non-esd - aware program. - -6) Ask for help on the sound list or send E-MAIL to the - sound driver author/maintainer. - -7) Turn on debug in drivers/sound/sound_config.h (DEB, DDB, MDB). - -8) If the system reports insufficient DMA memory then you may want to - load sound with the "dmabufs=1" option. Or in /etc/conf.modules add - - preinstall sound dmabufs=1 - - This makes the sound system allocate its buffers and hang onto them. - - You may also set persistent DMA when building a 2.4.x kernel. - - -Configuring Sound: -================== - -There are several ways of configuring your sound: - -1) On the kernel command line (when using the sound driver(s) - compiled in the kernel). Check the driver source and - documentation for details. - -2) On the command line when using insmod or in a bash script - using command line calls to load sound. - -3) In /etc/modprobe.d/*conf when using modprobe. - -4) Via Red Hat's GPL'd /usr/sbin/sndconfig program (text based). - -5) Via the OSS soundconf program (with the commercial version - of the OSS driver. - -6) By just loading the module and let isapnp do everything relevant - for you. This works only with a few drivers yet and - of course - - only with isapnp hardware. - -And I am sure, several other ways. - -Anyone want to write a linuxconf module for configuring sound? - - -Module Loading: -=============== - -When a sound card is first referenced and sound is modular, the sound system -will ask for the sound devices to be loaded. Initially it requests that -the driver for the sound system is loaded. It then will ask for -sound-slot-0, where 0 is the first sound card. (sound-slot-1 the second and -so on). Thus you can do - -alias sound-slot-0 sb - -To load a soundblaster at this point. If the slot loading does not provide -the desired device - for example a soundblaster does not directly provide -a midi synth in all cases then it will request "sound-service-0-n" where n -is - - 0 Mixer - - 2 MIDI - - 3, 4 DSP audio - - -For example, I use the following to load my Soundblaster PCI 128 -(ES 1371) card first, followed by my SoundBlaster Vibra 16 card, -then by my TV card: - -# Load the Soundblaster PCI 128 as /dev/dsp, /dev/dsp1, /dev/mixer -alias sound-slot-0 es1371 - -# Load the Soundblaster Vibra 16 as /dev/dsp2, /dev/mixer1 -alias sound-slot-1 sb -options sb io=0x240 irq=5 dma=1 dma16=5 mpu_io=0x330 - -# Load the BTTV (TV card) as /dev/mixer2 -alias sound-slot-2 bttv -alias sound-service-2-0 tvmixer - -pre-install bttv modprobe tuner ; modprobe tvmixer -pre-install tvmixer modprobe msp3400; modprobe tvaudio -options tuner debug=0 type=8 -options bttv card=0 radio=0 pll=0 - - -For More Information (RTFM): -============================ -1) Information on kernel modules: manual pages for insmod and modprobe. - -2) Information on PnP, RTFM manual pages for isapnp. - -3) Sound-HOWTO and Sound-Playing-HOWTO. - -4) OSS's WWW site at http://www.opensound.com. - -5) All the files in Documentation/sound. - -6) The comments and code in linux/drivers/sound. - -7) The sndconfig and rhsound documentation from Red Hat. - -8) The Linux-sound mailing list: sound-list@redhat.com. - -9) Enlightenment documentation (for info on esd) - http://www.tux.org/~ricdude/EsounD.html. - -10) ALSA home page: http://www.alsa-project.org/ - - -Contact Information: -==================== -Wade Hampton: (whampton@staffnet.com) - |