From 7012b2dac71988f61b520b33c70c63be372b5994 Mon Sep 17 00:00:00 2001 From: James Courtier-Dutton Date: Fri, 28 Jul 2006 22:27:56 +0100 Subject: [ALSA] snd-emu10k1: Add a comment explaining the conversion function for dB gain. Signed-off-by: James Courtier-Dutton Signed-off-by: Jaroslav Kysela --- sound/pci/emu10k1/emufx.c | 1 + 1 file changed, 1 insertion(+) (limited to 'sound/pci/emu10k1') diff --git a/sound/pci/emu10k1/emufx.c b/sound/pci/emu10k1/emufx.c index 00fc904..13cd6ce 100644 --- a/sound/pci/emu10k1/emufx.c +++ b/sound/pci/emu10k1/emufx.c @@ -267,6 +267,7 @@ static const u32 treble_table[41][5] = { { 0x37c4448b, 0xa45ef51d, 0x262f3267, 0x081e36dc, 0xfd8f5d14 } }; +/* dB gain = (float) 20 * log10( float(db_table_value) / 0x8000000 ) */ static const u32 db_table[101] = { 0x00000000, 0x01571f82, 0x01674b41, 0x01783a1b, 0x0189f540, 0x019c8651, 0x01aff763, 0x01c45306, 0x01d9a446, 0x01eff6b8, -- cgit v1.1