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Date: Mon, 24 Sep 2018 13:04:39 +0300
From: fesse <fesse@mail.ru>
To: freebsd-drivers@freebsd.org
Subject: Meaning of SND_FORMAT macro parameters (used in sound subsystem)
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Good day to everyone,

SND_FORMAT macro is defined in sound.h:

#define SND_FORMAT(f, c, e) (AFMTT_ENCODING(f) | (((c) << AFMT_CHANNEL_SHIFT) & AFMT_CHANNEL_MASK) | (((e) << AFMT_EXTCHANNEL_SHIFT) & AFMT_EXTCHANNEL_MASK)).

Many sound drivers define data format like this: SND_FORMAT(AFMT_S16_LE, 2, 0);

Sound guys, tell me please what means "2" and "0", i.e. "c" and "e" macro arguments. I really in doubt...