'Twas brillig, and Raymond Yau at 04/10/10 12:09 did gyre and gimble: > 2010/10/1 Clemens Ladisch <clemens@xxxxxxxxxx> > >> Takashi Iwai wrote: >>> Mark Brown wrote: >>>> On Thu, Sep 30, 2010 at 04:09:56PM +0100, Colin Guthrie wrote: >>>>> *shouldn't* use them, but at present it does and they *are* active >> and >>>>> used, so it's not an issue for me), the problem is rather one of >> setting >>>>> Master (not PCM) to 0% aka -46.5dB causes some kind of auto-mute that >>>>> cuts off all sound. It shouldn't do that. >>>> >>>> Is this perhaps just an error in the TLV information - should it be >>>> flagging that the minimim gain is mute but isn't? >>> >>> There is no clear (or consistent) definition in HD-audio codec, I guess. >> >> The HDA spec is quite clear that muting is done only with the mute bit. >> >>> Some chips do mute at 0 and some not. >> >> Those that do are violating the specification. >> >> But we have to support them anyway. >> Colin, please tell us the IDs of your codec so that we can add a TLV >> workaround to the driver. >> >> >> Regards, >> Clemens >> >> > Actually, the softvol plugin behave as the same way as Colin describe since > when the resolution is 2 , the softvol become a mute switch > > http://git.alsa-project.org/?p=alsa-lib.git;a=commit;h=f78af4ab0412052aabb74c9122a8d8f3ab6d45e6 > > So the question is why -51dB is selected as min_dB > > Is this value enough for S16_LE or S32_LE for hda-intel ? > > http://git.alsa-project.org/?p=alsa-kernel.git;a=commitdiff;h=eacbb9dba6b4c982a0217ea2c7d15db88d4fda37;hp=d91b424d6d7bda0773b6b6b606d48d089c4f5115 > > As those DACs support -120dB to 0dB , but the driver can actually limit the > dB range to -60dB to 0dB . so the minimum volume -60dB is definitly not mute > in this case > > why -60dB is selected ? Just for clarity, the 0 -> -51dB range is for the PCM control (i.e. softvol) only. The Master control gives me -46.5dB in addtiion to that giving a total of -97.5dB. This still isn't as high as the -120dB you are mentioning, but it's a lot closer. Of course I am lucky in that my Master apparently works fine but for those souls without any Master control, I presume the full range should be offered by the PCM softvol? Col -- Colin Guthrie gmane(at)colin.guthr.ie http://colin.guthr.ie/ Day Job: Tribalogic Limited [http://www.tribalogic.net/] Open Source: Mageia Contributor [http://www.mageia.org/] PulseAudio Hacker [http://www.pulseaudio.org/] Trac Hacker [http://trac.edgewall.org/] _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
