diff options
| author | Dana Conrad <dconrad@fastmail.com> | 2021-08-09 19:22:52 -0500 |
|---|---|---|
| committer | Solomon Peachy <pizza@shaftnet.org> | 2021-08-12 10:07:49 +0000 |
| commit | 6de6e1459de28bef919b869ee757474c615cb787 (patch) | |
| tree | ecf10a64809863d1cc3626a3b92dec856b937c4e /firmware | |
| parent | 235e41578be60135c8ad682e05440a5b9142ce69 (diff) | |
Eros Q Hosted: Apply DC Bias to PCM Data
Similar to the native port, the hosted port benefits from
adding a -1 dc bias to the PCM data. This prevents almost
all clicking artifacts.
Change-Id: Ic6378716774b6d88df23c476e2ef54d49f33dc72
Diffstat (limited to 'firmware')
| -rw-r--r-- | firmware/export/erosqlinux_codec.h | 2 | ||||
| -rw-r--r-- | firmware/target/hosted/pcm-alsa.c | 9 |
2 files changed, 9 insertions, 2 deletions
diff --git a/firmware/export/erosqlinux_codec.h b/firmware/export/erosqlinux_codec.h index b6ab58fa74..2ed1ae11cf 100644 --- a/firmware/export/erosqlinux_codec.h +++ b/firmware/export/erosqlinux_codec.h @@ -3,6 +3,8 @@ #define AUDIOHW_CAPS (LINEOUT_CAP) +#define PCM_DC_OFFSET_VALUE -1 + AUDIOHW_SETTING(VOLUME, "dB", 0, 2, -74, 0, -40) //#define AUDIOHW_NEEDS_INITIAL_UNMUTE diff --git a/firmware/target/hosted/pcm-alsa.c b/firmware/target/hosted/pcm-alsa.c index 13ebbbcbeb..68002d8158 100644 --- a/firmware/target/hosted/pcm-alsa.c +++ b/firmware/target/hosted/pcm-alsa.c @@ -68,6 +68,11 @@ #warning "MIX_FRAME_SAMPLES <1024 may cause dropouts!" #endif +/* PCM_DC_OFFSET_VALUE is a workaround for eros q hardware quirk */ +#if !defined(PCM_DC_OFFSET_VALUE) +# define PCM_DC_OFFSET_VALUE 0 +#endif + static const snd_pcm_access_t access_ = SND_PCM_ACCESS_RW_INTERLEAVED; /* access mode */ #if defined(HAVE_ALSA_32BIT) static const snd_pcm_format_t format = SND_PCM_FORMAT_S32_LE; /* sample format */ @@ -359,8 +364,8 @@ static bool copy_frames(bool first) sample_t *sample_ptr = &frames[2*(period_size-frames_left)]; for (int i = 0; i < nframes; i++) { - *sample_ptr++ = *pcm_ptr++ * dig_vol_mult_l; - *sample_ptr++ = *pcm_ptr++ * dig_vol_mult_r; + *sample_ptr++ = (*pcm_ptr++ * dig_vol_mult_l) + PCM_DC_OFFSET_VALUE; + *sample_ptr++ = (*pcm_ptr++ * dig_vol_mult_r) + PCM_DC_OFFSET_VALUE; } } else |