From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752876AbbEFFlR (ORCPT ); Wed, 6 May 2015 01:41:17 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:51059 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751200AbbEFFlP (ORCPT ); Wed, 6 May 2015 01:41:15 -0400 Date: Tue, 5 May 2015 22:41:13 -0700 From: Kenneth Westfield To: Srinivas Kandagatla Cc: Patrick Lai , Mark Brown , Rob Herring , Pawel Moll , Ian Campbell , Kumar Gala , Banajit Goswami , Liam Girdwood , Jaroslav Kysela , Takashi Iwai , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, alsa-devel@alsa-project.org, linux-arm-msm@vger.kernel.org Subject: Re: [alsa-devel] [RFC PATCH 14/14] ASoC: qcom: document apq8016 machine driver bindings Message-ID: <20150506054113.GB5639@kwestfie-linux.qualcomm.com> Mail-Followup-To: Srinivas Kandagatla , Patrick Lai , Mark Brown , Rob Herring , Pawel Moll , Ian Campbell , Kumar Gala , Banajit Goswami , Liam Girdwood , Jaroslav Kysela , Takashi Iwai , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, alsa-devel@alsa-project.org, linux-arm-msm@vger.kernel.org References: <1430414148-10869-1-git-send-email-srinivas.kandagatla@linaro.org> <1430414306-11469-1-git-send-email-srinivas.kandagatla@linaro.org> <20150503000307.GG27804@kwestfie-linux.qualcomm.com> <55486E6D.9010402@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <55486E6D.9010402@linaro.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 05, 2015 at 12:17:01AM -0700, Srinivas Kandagatla wrote: > On 03/05/15 01:03, Kenneth Westfield wrote: > >On Thu, Apr 30, 2015 at 06:18:26PM +0100, Srinivas Kandagatla wrote: > >>This patch adds bindings for apq8016 machine driver. > >>On APQ8016 4 MI2S can be configured to different sinks like internal > >>codec/external codec, this connection is controlled via 2 iomux > >>registers. > >> > >>+sound: sound { > >>+ compatible = "qcom,apq8016-sndcard"; > >>+ reg = <0x07702000 0x4>, <0x07702004 0x4>; > >>+ reg-names = "mic-iomux", "spkr-iomux"; > >>+ qcom,model = "DB410c"; > >>+ > >>+ /* I2S - Internal codec */ > >>+ internal-dai-link@0 { > >>+ cpu { /* PRIMARY */ > >>+ sound-dai = <&lpass MI2S_PRIMARY>; > >>+ }; > >>+ codec { > >>+ sound-dai = <&wcd_codec 0>; > >>+ }; > >>+ }; > >>+ > >>+ /* External Primary or External Secondary -ADV7533 HDMI */ > >>+ external-dai-link@0 { > >>+ external; > >>+ cpu { /* QUAT */ > >>+ sound-dai = <&lpass MI2S_QUATERNARY>; > >>+ }; > >>+ codec { > >>+ sound-dai = <&adv_bridge 0>; > >>+ }; > >>+ }; > >>+}; > > > >OK, although I will need to double-check this with the spec, it seems > >(from the patches) that there are 4 I2S ports, 2 of which are being > >used. Usually, multi-channel audio is sent to the primary dai (which > >is MI2S), which then gets sent to the other ports by HW. If that holds > >true for this SOC, then the external cpu dai should be labelled I2S, > >not MI2S. If not, then both should be labelled as I2S (and the DAI > >channel constraints should be reduced to 1-2). > > > I have got very limited access to documentation, which obviously > does not have any info related to channel capabilities. I was > thinking that all the playback ports support multi-channel. I might > be wrong though. After checking the specs, the four playback DAIs are, in fact, multi-channel. Therefore, MI2S_ is the correct prefix for them. > > >Looking at patch 12, the internal DAI is labelled Headset and the > >external DAI is labelled HDMI. > This naming is very specific to the SBC board. > > I will check the spec to see if the QUAT > >I2S port can handle multi-channel. > External HDMI bridge on the other side only supports 2-channels, but > if you can re-check on the channel capabilities would be good. Ah, ok. Then no need to worry about multi-channel playback. Just need to ensure the codec drivers constrain the channels to mono/stereo. -- Kenneth Westfield Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project