ZV port patch for YMF7152002,2.3.  ver 0.1   1st release1. Abstract  This patch adds the following function to opl3sa2 driver in  alsa-driver-0.5.12a. (YMF715 only)   - enable/disable ZV port2. Test system  I tested this patch on the following system.  Machine:  Toshiba Libretto100     Sound   : YAMAHA   YMF715(OPL3SA2)     Graphics: NeoMagic NM2160     PCIC    : Toshiba  ToPIC97  OS: Linux-2.4.17  ALSA: 0.5.12a3. How to apply this patch  cd alsa-driver-0.5.12a/cards  patch -p0 -s < card-opl3sa2.c.diff  make  make install 4. Utility  - zv-snd (shell script)    Enable ZV port and set its volume to 30%.    If there is a audio stream from ZV port, you can hear it.    (note)       In YMF715, ZV port and internal FM synthesizer(OPL3) are      exclusive.      And the volume of these source are controlled by "FM volume      slider".s.nomura@mba.nifty.ne.jp