diff options
| author | Amaury Pouly <amaury.pouly@gmail.com> | 2016-08-21 20:31:55 +0100 |
|---|---|---|
| committer | Amaury Pouly <amaury.pouly@gmail.com> | 2016-12-12 13:13:13 +0100 |
| commit | 4d526df7ac7132afe91292f3821ae46853fa9984 (patch) | |
| tree | 628f484814189ddd023f405cfd26bd2c82e7a8c5 /firmware | |
| parent | 69ea311398ed26797aec837f26b18c2e3e50744c (diff) | |
wm8975: document audiohw settings
Change-Id: I0456f85e4ebc821c23e25026fbee3d8cf7526ee7
Diffstat (limited to 'firmware')
| -rw-r--r-- | firmware/drivers/audio/wm8975.c | 2 | ||||
| -rw-r--r-- | firmware/export/wm8975.h | 5 |
2 files changed, 7 insertions, 0 deletions
diff --git a/firmware/drivers/audio/wm8975.c b/firmware/drivers/audio/wm8975.c index 88be2cf5ce..a1af1331f2 100644 --- a/firmware/drivers/audio/wm8975.c +++ b/firmware/drivers/audio/wm8975.c @@ -296,6 +296,8 @@ void audiohw_disable_recording(void) wm8975_write(PWRMGMT1, wm8975_regs[PWRMGMT1]); } +/* volume in 0 .. 63, corresponds to -17.25dB .. 30dB in steps of 0.75dB + * microphone has an extra 20dB boost so 0 .. 63 corresponds to 2.75dB .. 50dB */ void audiohw_set_recvol(int left, int right, int type) { switch (type) diff --git a/firmware/export/wm8975.h b/firmware/export/wm8975.h index cdae7af865..b8ef17910c 100644 --- a/firmware/export/wm8975.h +++ b/firmware/export/wm8975.h @@ -29,8 +29,13 @@ AUDIOHW_SETTING(VOLUME, "dB", 0, 1, -74, 6, -25) AUDIOHW_SETTING(BASS, "dB", 0, 1, -6, 9, 0) AUDIOHW_SETTING(TREBLE, "dB", 0, 1, -6, 9, 0) #ifdef HAVE_RECORDING +/* The input PGAs have a gain range from -17.25dB .. 30dB in steps of 0.75dB + * Values: 0, 1, ..., 63 + * => -17.25, -16.5dB, ..., 30.0dB */ AUDIOHW_SETTING(LEFT_GAIN, "dB", 1, 1, 0, 63, 23, ((val - 23) * 15) / 2) AUDIOHW_SETTING(RIGHT_GAIN, "dB", 1, 1, 0, 63, 23, ((val - 23) * 15) / 2) +/* The microphone has an extra 20dB boost before the input PGA so 0 .. 63 + * corresponds to 2.75dB .. 50dB */ AUDIOHW_SETTING(MIC_GAIN, "dB", 1, 1, 0, 63, 0, ((val - 23) * 15) / 2 + 200) #endif /* HAVE_RECORDING */ |