[pulseaudio-discuss] [PATCH] alsa-mixer: When setting hw volume, round always up with playback and always down with capture.

[Colin Guthrie]

'Twas brillig, and David Henningsson at 16/05/11 07:23 did gyre and gimble:
> On 2011-05-15 16:45, Tanu Kaskinen wrote:
>> On Sun, 2011-05-15 at 17:43 +0300, Tanu Kaskinen wrote:
>>> This was discussed on the mailing list:
>>>
>>> https://tango.0pointer.de/pipermail/pulseaudio-discuss/2011-May/010091.html
>>>
>>> ---
>>>   src/modules/alsa/alsa-mixer.c |    2 +-
>>>   1 files changed, 1 insertions(+), 1 deletions(-)
>>>
>>> diff --git a/src/modules/alsa/alsa-mixer.c
>>> b/src/modules/alsa/alsa-mixer.c
>>> index f236da0..8375a2f 100644
>>> --- a/src/modules/alsa/alsa-mixer.c
>>> +++ b/src/modules/alsa/alsa-mixer.c
>>> @@ -893,7 +893,7 @@ static int element_set_volume(pa_alsa_element *e,
>>> snd_mixer_t *m, const pa_chann
>>>
>>>           if (e->has_dB) {
>>>               long value = to_alsa_dB(f);
>>> -            int rounding = value>  0 ? -1 : +1;
>>> +            int rounding = e->direction == PA_ALSA_DIRECTION_OUTPUT
>>> ? +1 : -1;
>>>
>>>               if (e->volume_limit>= 0&&  value>  (e->max_dB * 100))
>>>                   value = e->max_dB * 100;
>>
>> David, are you happy with this change, or does this require more
>> discussion?
>>
> 
> I think it's OK. I think your theory is at least as good as mine, so
> let's give it a try. For HDA Intel this does not make much of a
> difference as Playback almost always only goes up to 0 dB whereas
> Recording usually is above 0 dB (although not always).

Cool. I'll have to try this out in my tree with Source Output volumes as
I'm having a brain freeze as to whether or not this is the right way
round for what I observed. If it's not working I'll post back with some
numbers.

> Might be worth adding a comment referring to the discussion behind the
> reasoning though.

Yeah, I think a comment would be wise when this goes in.

I'll take care of it and report back sometime this week.

Col

-- 

Colin Guthrie
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http://colin.guthr.ie/

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