patch-2.1.94 linux/Documentation/sound/Opti

• Lines: 217
• Date: Wed Apr 8 15:34:23 1998
• Orig file: v2.1.93/linux/Documentation/sound/Opti
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.93/linux/Documentation/sound/Opti linux/Documentation/sound/Opti
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+Support for the OPTi 82C931 chip
+--------------------------------
+Note: parts of this README file apply also to other
+cards that use the mad16 driver.
+
+Some items in this README file are based on features
+added to the sound driver after Linux-2.1.91 was out.
+By the time of writing this I do not know which official
+kernel release will include these features.
+Please do not report inconsistencies on older Linux
+kernels.
+
+The OPTi 82C931 is supported in its non PnP mode.
+Usually you do not need to set jumpers etc... The sound driver
+will check the card status and if it is required it will
+force the card into a mode in which it can be programmed.
+
+If you have another OS installed on your computer it is recommended
+that Linux and the other OS use the same resources.
+
+Also, it is recommended that resources specified in /etc/conf.modules
+and resources specified in /etc/isapnp.conf agree.
+
+Compiling the sound driver
+--------------------------
+I highly recommend that you build a modularized sound driver.
+This document does not cover sound-driver which is built in
+the kernel.
+
+Sound card support should be enabled as a module (chose m).
+Answer 'm' for  these items:
+  Generic OPL2/OPL3 FM synthesizer support			(CONFIG_ADLIB)
+  Microsoft Sound System support				(CONFIG_MSS)
+  Support for OPTi MAD16 and/or Mozart based cards	 	(CONFIG_MAD16)
+  FM synthesizer (YM3812/OPL-3) support				(CONFIG_YM3812)
+
+The configuration menu may ask for addresses, irq lines or dma
+channels. If the card is used as a module the module loading
+options will override these values.
+
+For the OPTi 931 you can answer 'n' to:
+  Support MIDI in older MAD16 based cards (requires SB)		(CONFIG_MAD16_OLDCARD)
+If you do need MIDI support in a Mozart or C928 based card you
+need to answer 'm' to the above question. In that case you will
+also need to answer 'm' to:
+  '100% Sound Blaster compatibles (SB16/32/64, ESS, Jazz16) support' (CONFIG_SB)
+
+Go on and compile your kernel and modules. Install the modules. Run depmod -a.
+
+Using isapnptools
+-----------------
+In most systems with a PnP bios you do not need to use isapnp. The
+initialization provided by the bios is sufficient for the driver
+to pick up the card and continue initialization.
+
+If that fails, or if you have other PnP cards, you need to use isapnp
+to initialize the card.
+This was tested with isapnptools-1.11 but I recommend that you use
+isapnptools-1.13 (or newer). Run pnpdump to dump the information
+about your PnP cards. Then edit the resulting file and select
+the options of your choice. This file is normally installed as
+/etc/isapnp.conf.
+
+The driver had one limitation WRT io port resources.
+IO3 base should be 0x0E0C. Isapnp allows other io ports but this
+address is hard-coded into the driver.
+
+Using kmod and autoloading the sound driver
+-------------------------------------------
+Comment: as of linux-2.1.90 kmod is replacing kerneld.
+The config file '/etc/conf.modules' is used as before.
+
+This is the sound part of my /etc/conf.modules file.
+Following that I will explain each line.
+
+alias mixer0 mad16
+alias audio0 mad16
+alias midi0  mad16
+alias synth0 opl3
+options sb mad16=1
+options mad16 irq=10 dma=0 dma16=1 io=0x530 joystick=1 cdtype=0
+options opl3 io=0x388
+post-install mad16 /sbin/ad1848_mixer_reroute 14 8 15 3 16 6
+
+Explain:
+
+alias mixer0 mad16
+alias audio0 mad16
+alias midi0  mad16
+alias synth0 opl3
+
+When any sound device is opened the kernel requests auto-loading
+of char-major-14. There is a built-in alias that translates this
+request to loading the main sound module. The main sound module
+contains only common code which is needed by all the sound drivers,
+and the driver for /dev/sndstat.
+
+The sound module in it's turn will request loading of a sub-driver
+for mixer, audio, midi or synthesizer device. The first 3 are
+supported by the mad16 driver. The synth device is supported
+by the opl3 driver.
+
+There is currently no way to autoload the sound device driver
+if more than one card is installed.
+
+options sb mad16=1
+
+This is left for historical reason. If you enable the
+config option 'Support MIDI in older MAD16 based cards (requires SB)'
+or if you use an older mad16 driver it will force loading of the
+SoundBlaster driver. This option tells the SB driver not to look
+for a SB card but to wait for the mad16 driver.
+
+options mad16 irq=10 dma=0 dma16=1 io=0x530 joystick=1 cdtype=0
+options opl3 io=0x388
+
+post-install mad16 /sbin/ad1848_mixer_reroute 14 8 15 3 16 6
+
+This sets resources and options for the mad16 and opl3 drivers.
+I use 2 dma channels (only one is required) to enable full duplex.
+joystick=1 enables the joystick port. cdtype=0 disables the cd port.
+You can also set mpu_io and mpu_irq in the mad16 options for the
+uart401 driver.
+
+This tells modprobe to run /sbin/ad1848_mixer_reroute after
+mad16 is successfully loaded and initialized. The source
+for ad1848_mixer_reroute is appended to the end of this readme
+file. It is impossible for the sound driver to know the actual
+connections to the mixer. The 3 inputs intended for cd, synth
+and line-in are mapped to the generic inputs line1, line2 and
+line3. This program reroutes these mixer channels to their
+right names (note the right mapping depends on the actual sound
+card that you use).
+The numeric parameters mean:
+ 14=line1 8=cd    - reroute line1 to the CD input.
+ 15=line2 3=synth - reroute line2 to the synthesizer input.
+ 16=line3 6=line  - reroute line3 to the line input.
+For reference on other input names look at the file
+/usr/include/linux/soundcard.h.
+
+Using a joystick
+-----------------
+You must enable a joystick in the mad16 options. (also
+in /etc/isapnp.conf if you use it).
+Tested with regular analog joysticks.
+
+A CDROM drive connected to the sound card
+-----------------------------------------
+The 82C931 chip has support only for secondary ATAPI cdrom.
+(cdtype=8). Loading the mad16 driver resets the C931 chip
+and if a cdrom was already mounted it may cause a complete
+system hang. Do not use the sound card if you have an alternative.
+If you do use the sound card it is important that you load
+the mad16 driver (use "modprobe mad16" to prevent auto-unloading)
+before the cdrom is accessed the first time.
+
+Using the sound driver built-in the kernel may help here. but...
+Most new systems have a PnP bios and also two IDE controllers.
+The IDE controller on the sound card may be needed only on older
+systems (which have only one IDE controller) but these systems
+also do not have a PnP bios - requiring isapnptoosl and a modularized
+driver.
+
+Known problems
+--------------
+1. See the section on "A CDROM drive connected to the sound card".
+
+2. On my system the codec cannot capture companded sound samples.
+   (eg., recording from /dev/audio). When any companded capture is
+   requested I get a stereo-16 bit samples instead. Playback of
+   companded samples work well. Apparently this problem is not common
+   to all C931 based cards. I do not know how to identify cards that
+   have this problem.
+
+Source for ad1848_mixer_reroute.c
+---------------------------------
+#include <stdio.h>
+#include <fcntl.h>
+#include <linux/soundcard.h>
+
+static char *mixer_names[SOUND_MIXER_NRDEVICES] =
+	SOUND_DEVICE_LABELS;
+
+int
+main(int argc, char **argv) {
+	int val, from, to;
+	int i, fd;
+
+	fd = open("/dev/mixer", O_RDWR);
+	if(fd < 0) {
+		perror("/dev/mixer");
+		return 1;
+	}
+
+	for(i = 2; i < argc; i += 2) {
+		from = atoi(argv[i-1]);
+		to = atoi(argv[i]);
+
+		if(to == SOUND_MIXER_NONE)
+			fprintf(stderr, "%s: turning off mixer %s\n",
+				argv[0], mixer_names[to]);
+		else
+			fprintf(stderr, "%s: rerouting mixer %s to %s\n",
+				argv[0], mixer_names[from], mixer_names[to]);
+
+		val = from << 8 | to;
+
+		if(ioctl(fd, SOUND_MIXER_PRIVATE2, &val)) {
+			perror("AD1848 mixer reroute");
+			return 1;
+		}
+	}
+
+	return 0;
+}
+