diff options
Diffstat (limited to 'firmware/drivers/audio/wm8978.c')
-rw-r--r-- | firmware/drivers/audio/wm8978.c | 21 |
1 files changed, 9 insertions, 12 deletions
diff --git a/firmware/drivers/audio/wm8978.c b/firmware/drivers/audio/wm8978.c index 3a86ef204e..69ae608e5d 100644 --- a/firmware/drivers/audio/wm8978.c +++ b/firmware/drivers/audio/wm8978.c | |||
@@ -155,20 +155,17 @@ static void wmc_write_masked(unsigned int reg, unsigned int bits, | |||
155 | * (000000...111111) */ | 155 | * (000000...111111) */ |
156 | static int vol_tenthdb2hw(int db) | 156 | static int vol_tenthdb2hw(int db) |
157 | { | 157 | { |
158 | /* -90dB to +6dB 1dB steps (96 levels) 7bits */ | 158 | /* att DAC AMP result |
159 | /* 1100000 == +6dB (0x60,96) */ | 159 | +6dB 0 +6 96 |
160 | /* 1101010 == 0dB (0x5a,90) */ | 160 | 0dB 0 0 90 |
161 | /* 1000001 == -57dB (0x21,33,DAC) */ | 161 | -57dB 0 -57 33 |
162 | /* 0000001 == -89dB (0x01,01) */ | 162 | -58dB -1 -57 32 |
163 | /* 0000000 == -90dB (0x00,00,Mute) */ | 163 | -89dB -32 -57 1 |
164 | if (db < VOLUME_MIN) | 164 | -90dB -oo -oo 0 */ |
165 | { | 165 | if (db <= -900) |
166 | return 0x0; | 166 | return 0x0; |
167 | } | ||
168 | else | 167 | else |
169 | { | 168 | return db / 10 - -90; |
170 | return (db - VOLUME_MIN) / 10; | ||
171 | } | ||
172 | } | 169 | } |
173 | 170 | ||
174 | void audiohw_preinit(void) | 171 | void audiohw_preinit(void) |