Specifications

each option is for. Select the appropriate options to the best of your knowledge.

After configuring the options you should compile and install the new kernel as per the Kernel HOWTO.

4.4. Creating the Device Files

For proper operation, device file entries must be created for the sound devices. These are normally created for

you during installation of your Linux system. A quick check can be made using the command listed below. If

the output is as shown (the date stamp will vary) then the device files are almost certainly okay.

% ls −l /dev/dsp

crw−rw−rw− 1 root root 14, 3 Apr 25 1995 /dev/dsp

Note that having the right device files there doesn't guarantee anything on its own. The kernel driver must

also be loaded or compiled in before the devices will work (more on that later).

In rare cases, if you believe the device files are wrong, you can recreate them. Most Linux distributions have

a /dev/MAKEDEV script which can be used for this purpose.

Note that if you are using the devfs filesystem support in the 2.4 kernels, the sound device files are actually

found in /dev/sound, but there will be symbolic links to the older devices, such as /dev/dsp.

4.5. Booting Linux and Testing the Installation

You should now be ready to boot the new kernel and test the sound drivers. Follow your usual procedure for

installing and rebooting the new kernel (keep the old kernel around in case of problems, of course).

If you are using loadable kernel modules for sound, you will need to load them using the modprobe

command for the appropriate drivers, e.g. run the command modprobe sb for a SoundBlaster card.

After booting, or loading the kernel modules, check for a message such as the following using the

dmesg command:

sb: Creative SB AWE64 PnP detected

sb: ISAPnP reports 'Creative SB AWE64 PnP' at i/o 0x220, irq 5, dma 1, 5

SB 4.16 detected OK (220)

sb: 1 Soundblaster PnP card(s) found.

Crystal 4280/46xx + AC97 Audio, version 1.22.32, 10:28:40 Apr 28 2001

cs46xx: Card found at 0xf4100000 and 0xf4000000, IRQ 11

cs46xx: Thinkpad 600X/A20/T20 (1014:0153) at 0xf4100000/0xf4000000, IRQ 11

ac97_codec: AC97 Audio codec, id: 0x4352:0x5914 (Cirrus Logic CS4297A rev B)

The message should indicate that a sound card was found and match your sound card type and jumper

settings (if any). The driver may also display some error messages and warnings if you have incorrectly

configured the driver or chosen the wrong one.

The Linux Sound HOWTO

4.4. Creating the Device Files 11