At Wed, 10 Jul 2013 23:42:18 +0200, Tormen wrote:
On 10/07/13 17:30, Takashi Iwai wrote:
At Tue, 09 Jul 2013 11:53:47 -0700, Adam Williamson wrote:
On 2013-07-08 10:48, Takashi Iwai wrote:
Ah, yes, I'd forgotten about that little wrinkle. I don't pretend to be following the exact details of the planned fix here, but just as a high-level remark, this 'extra mic jack' seems very much like an implementation detail for the noise cancellation which Linux does not do in any case (AFAIK). It wouldn't make sense to me to expose it as a 'normal' mic jack, exactly. It's not like you can plug an actual microphone into this 'mic jack' and use it. How will it be exposed exactly after the patch, tiwai?
Well, Tormen's description sounds like it being a mic for a headset, no?
I did mention though:
(a) the Notebook came with Noise-cancelling headsets, but theyare small in-ear plugs so there is no place for noise-cancelling logic in the plugs ...
No, at least IIRC - the special headphones that come with the system aren't for voice calling or whatever, they're active noise cancelling earphones. http://forum.notebookreview.com/sony/501220-sony-noise-cancelling-ear-phones... is a thread about them, for e.g.
OK, then it's not suitable to handle it as a headset. I expected it being rather a standard TRRS connector.
OK, I looked into that and here are my findings:
People reported about two different models of noise cancelling headphones in the context of Sony VAIO VPCZ Notebooks. Both are 5-conductor jacks.
You can see them both here: http://attachment.imp3.net/forum/month_1103/11030618490735852e6e2772f8.jpg The right side version is better seen here with it's extra "notch" adding the 5th conductor to an otherwise 4.5mm 4-conductor TRRS jack (3 black rings + notch) http://pic.yupoo.com/melly/C8LBXQYf/LBWc6.jpg The left side version is a 3.5 mm 5-conductor TRRS phone connector (4 black rings) http://img03.taobaocdn.com/bao/uploaded/i3/T1xd9qXcNbXXaS84UV_020744.jpg
I do have the LEFT side version (the one with 4 black rings)
Important:
- This TRRS headset jack works just fine when you plug a stereo
headphones (3-conductor version).
- And It seems to also work fine with a 4-conductor version (headphone
- mic smartphone headset) - see about "Mic 1" below.
More details about the wiring (from an alsamixer viewpoint in (debian) kernel 3.9.6):
+++ "Mic 1" refers to the earplug Stereo mic channel. The "Microphone Boost 1" controls nicely this "Mic 1". When capturing from "Mic 1" in alsamixer (with 3.9.6 debian kernel without any new patch):
* plugging a standard 4-conductor TRRS (headset + MONO microphonecombination like common for smartphones these days with 3 black rings) -> the microphone comes through on the right microphone channel Unfortunately I don't have a headset + STEREO microphone combination at hand :/
* plugging the 5-conductor TRRS original noise cancelling headset(model Sony "mdr-nc021") -> the microphone in the /left/ earplug (it says "L" on the plug) comes through on the LEFT microphone channel + the microphone in the /right/ earplug (it says "R" on the plug) comes through on the RIGHT microphone channel
+++ "Mic" refers to the Mic TRRS standard Stereo jack which is beside the headset TRRS jack. The "Microphone Boost" controls nicely the "Mic" capture channel.
+++ "Internal" refers to the built in Stereo Microphone
+++ The "Digital" channel seems to have the exact same effect than the "Capture" channel (controlling the degree of amplification of the currently active capture source) There is certainly a deeper sense in the distinguishing both of them, but I don't get it :)
So this does make all perfect sense to me (especially "Mic 1") and I like the idea to further expose this quite /real/ stereo microphone channel "Mic 1".
Here is a small test recording I did using the (model Sony "mdr-nc021") headset: https://docs.google.com/file/d/0B9I6C680kzS1RFBOdWtaZXNIY00/edit?usp=sharing
(( maybe rename "Mic" to "Mic jack" and "Mic 1" to "Headphone Mic" ))
Thanks for the detailed analysis. So we should keep both inputs. A remaining question is whether to rename the control names, especially "Mic 1".
BTW, did you already test the patch? It's waiting for test feedback. Otherwise the fix can't be queued to upstream.
Takashi