For the softvol plugin the TLV data are written wrong, e.g. for the default values of min_dB = -51 dB and max_dB = 0 dB, alsactl generates the following state:
control.1 { iface MIXER name Master value.0 255 value.1 255 comment { access 'read write user' type INTEGER count 2 range '0 - 255' tlv '00000001000000080000000000000014' dbmin 0 dbmax 5100 dbvalue.0 5100 dbvalue.1 5100 } }
As both min_dB and max_dB can be negative numbers, the tlv type must not be unsigned. This fixes the TLV and the correct state is generated:
control.1 { iface MIXER name Master value.0 255 value.1 255 comment { access 'read write user' type INTEGER count 2 range '0 - 255' tlv '0000000100000008ffffec1400000014' dbmin -5100 dbmax 0 dbvalue.0 0 dbvalue.1 0 } }
Also tested for different combinations of min_dB and max_dB other than the default values.
Signed-off-by: Jörg Krause joerg.krause@embedded.rocks --- src/pcm/pcm_softvol.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/src/pcm/pcm_softvol.c b/src/pcm/pcm_softvol.c index 802aa4b..1748667 100644 --- a/src/pcm/pcm_softvol.c +++ b/src/pcm/pcm_softvol.c @@ -655,7 +655,7 @@ static void snd_pcm_softvol_dump(snd_pcm_t *pcm, snd_output_t *out)
static int add_tlv_info(snd_pcm_softvol_t *svol, snd_ctl_elem_info_t *cinfo) { - unsigned int tlv[4]; + int tlv[4]; tlv[0] = SND_CTL_TLVT_DB_SCALE; tlv[1] = 2 * sizeof(int); tlv[2] = svol->min_dB * 100; @@ -768,7 +768,7 @@ static int softvol_load_control(snd_pcm_t *pcm, snd_pcm_softvol_t *svol, } } else if (svol->max_val > 1) { /* check TLV availability */ - unsigned int tlv[4]; + int tlv[4]; err = snd_ctl_elem_tlv_read(svol->ctl, &cinfo->id, tlv, sizeof(tlv)); if (err < 0) add_tlv_info(svol, cinfo);