From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756113Ab2HIHvf (ORCPT ); Thu, 9 Aug 2012 03:51:35 -0400 Received: from moutng.kundenserver.de ([212.227.126.187]:57279 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754454Ab2HIHvd (ORCPT ); Thu, 9 Aug 2012 03:51:33 -0400 Date: Thu, 9 Aug 2012 09:51:28 +0200 From: Thierry Reding To: Takashi Iwai Cc: Jaroslav Kysela , David Henningsson , alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] ALSA: hda/realtek - Keep analog bypass muted on ALC892 Message-ID: <20120809075128.GA24808@avionic-0098.mockup.avionic-design.de> References: <1344494839-6942-1-git-send-email-thierry.reding@avionic-design.de> <20120809071848.GB6979@avionic-0098.mockup.avionic-design.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="yrj/dFKFPuw6o+aM" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-Provags-ID: V02:K0:srDzhFuQHq8UbbpgVaa8XnFVyxM95hj/XYu2LlGQgrY D7+CQP+eyNYkw/Y6/C9QczEHC8twlLUSoW9Uk5kXvLimND9bly UssL4AlwyVY02iPGkUR/yHM7KS+exjCYLgtCBa7eIAuf4xRRqk PE67zUYG8C8rKl+FtfSwo9uTS/5YbklwKF7z2olxvOG5I4AseL qS5TMtm1mg+L2HnCPBt0xmy5YzG9+y+vYWkmsRo1i5h0McvJ7J aU1EPKWJ14w7wnTUsCFx/qNxEjIgz+/LdcY8AH4Qwq49NGwNRw Jzova7XW7V2bxr932Ygm0+KG5eRr37ruH+HLyYCkp537ujr66t X+A5C/XXv3h90aUHJhFp9997eZrPl7ZZHAOPEsqmn/K7xXc2/1 z2LQqg8Stx6CUDnxA3ARrEPi0L+k2gr1zQ= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --yrj/dFKFPuw6o+aM Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Aug 09, 2012 at 09:33:43AM +0200, Takashi Iwai wrote: > At Thu, 9 Aug 2012 09:18:48 +0200, > Thierry Reding wrote: > >=20 > > On Thu, Aug 09, 2012 at 09:02:10AM +0200, Takashi Iwai wrote: > > > At Thu, 9 Aug 2012 08:47:19 +0200, > > > Thierry Reding wrote: > > > >=20 > > > > Unmuting the analog bypass causes any input to be directly bypassed= to > > > > the outputs, which is usually not expected by the user. > > > >=20 > > > > Signed-off-by: Thierry Reding > > > > --- > > > > Note that this patch could be generalized to include all codec vari= ants > > > > that have this second channel. As I don't have access to all the da= ta > > > > sheets I'll leave that decision up to somebody with more hardware > > > > available. > > >=20 > > > Hmm, are you really sure that this is exclusive switch between two? > > > All Realtek codecs with this mixer widget mixes two sources up. > > > Otherwise it must not be a "mixer" widget at all but it must be a > > > "selector" widget. > >=20 > > It's not an exclusive switch. But the second input is the analog bypass > > that basically takes the signal directly from the input path and routes > > it to the output. >=20 > Ah so you mean it as the analog loopback path. Yes. > > > And I haven't received a bug report regarding this although ALC892 is > > > no new chip and the auto-parser has been enabled for so long time. > >=20 > > I've seen this happen when feeding a signal into the CD-IN (NID 0x1c), > > which is then directly routed to the output, so I actually hear that > > signal at the output, even if there is no software loopback to capture > > the input and play it back via the DAC. > >=20 > > This is probably not a very common use-case, so maybe nobody else has > > come across it. Looking at the block diagram in the ALC892 datasheet > > (page 5) clearly shows where the input of this second switch comes from. > > I don't think this is intended to be unmuted by default, but only in > > very special cases where you actually want to pass the analog input > > signal directly to the output without going through the ADC and back out > > the DAC. >=20 > Each input has the analog loopback mixer switch (and off as default). > Why it doesn't suffice? I hadn't thought about that. I'll need to recheck if that solves the issue that I was seeing. Thierry --yrj/dFKFPuw6o+aM Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (GNU/Linux) iQIcBAEBAgAGBQJQI2wAAAoJEN0jrNd/PrOhhVgQAJK+zqS2HvMHS0LLuuvSGwOn Pqjktc21vhDMZeufm7kJutnPiqtsWv8cD1b5sXqfZeCzUgXBvDAUnrMuI03jMcGh PbrYLvan9cJdjgYwy3t8keY78rpbYFhXpLioI4p4L7PJh/sFyjU/1amOzD6mmpXJ o6X9UcSDzci+e/3TX/cEwkBecFCNY3oMnzjcYXpz0xNNqPxCWuolq6e4ATyvGSDv 7Cb8f5tMcOfqgFmbLtf9te0jg325Yy8g3X2dVq9LI6EUARXiZh03kMzwDfkFMN9E 9FpC85QPJJTIEu/U18lWcn3NiIqREdUE0gA83q/4Tl/+4RTplIgI43VK4CC0zhN+ S325lFp4JkfQHZUpHiSPwuBcal2od157kx7TdH40uY3mTKIbDpotSdAb+pd6jcn/ tWBS2DwFAE94Ao44RR8VcRZ/U2KedKSn+cNXkoHKWnXdnvfFyAOLz2/0iZf8p7xA v5+YK1M6/ei/kO+5V/eZQG1ThYXtiFpHm8+FK/bnryNUfsDEJYSfzyHgFT8hNtlk nPOeULCn3bcHHqBO3kSAvuWVWi3yFdNAjU4UiZs+7wwFPatwActHKsUwyp9g18lV HmsEhoJwWSmXjrHvXVrQEZ8IvwDKqdVTvMqQXJRw0lA+o6Ca6eB/UXa/yNyrD8Kg RcvxveeOQsChbZb4AY1E =KIGW -----END PGP SIGNATURE----- --yrj/dFKFPuw6o+aM--