From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_HIGH autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0EEE8C433F5 for ; Tue, 4 Sep 2018 13:55:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 576032082B for ; Tue, 4 Sep 2018 13:55:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="C0jQ4Ceb" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 576032082B Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=ti.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727337AbeIDSUe (ORCPT ); Tue, 4 Sep 2018 14:20:34 -0400 Received: from lelv0143.ext.ti.com ([198.47.23.248]:55450 "EHLO lelv0143.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726281AbeIDSUe (ORCPT ); Tue, 4 Sep 2018 14:20:34 -0400 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by lelv0143.ext.ti.com (8.15.2/8.15.2) with ESMTP id w84Dt7p9014396; Tue, 4 Sep 2018 08:55:07 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1536069307; bh=7OyTJEpEZdpEP2aw1bvM99B06xIBi/L5ma8brHxd0Z8=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=C0jQ4CebbFBKJxwXjqQNg+GrusEMjSHuzFO8YDhxl+1gBOqud6vcQ0WWA8ZSPTXkI yf1ITJT7y9+Yh2cayIcT4Ka2uWTAzu3ds7HVkm/a9JEbPEpGYuJojyveFlvjRXGp6u nL4blqRgTBpgMLOUarBe6TsvLwYlCrTgHZc8A/uc= Received: from DLEE101.ent.ti.com (dlee101.ent.ti.com [157.170.170.31]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id w84Dt70F030069; Tue, 4 Sep 2018 08:55:07 -0500 Received: from DLEE108.ent.ti.com (157.170.170.38) by DLEE101.ent.ti.com (157.170.170.31) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1466.3; Tue, 4 Sep 2018 08:55:07 -0500 Received: from dlep33.itg.ti.com (157.170.170.75) by DLEE108.ent.ti.com (157.170.170.38) with Microsoft SMTP Server (version=TLS1_0, cipher=TLS_RSA_WITH_AES_256_CBC_SHA) id 15.1.1466.3 via Frontend Transport; Tue, 4 Sep 2018 08:55:07 -0500 Received: from [172.22.184.106] (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep33.itg.ti.com (8.14.3/8.13.8) with ESMTP id w84Dt6p7001372; Tue, 4 Sep 2018 08:55:07 -0500 Subject: Re: [PATCH] ASoC: tlv320aic31xx: Add MICBIAS off setting To: Mark Brown CC: Liam Girdwood , Rob Herring , Mark Rutland , , , References: <20180831180507.28867-1-afd@ti.com> <20180903112656.GF10302@sirena.org.uk> From: "Andrew F. Davis" Message-ID: <701a066c-33e1-4476-7403-fdb9a3c366d8@ti.com> Date: Tue, 4 Sep 2018 08:55:06 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20180903112656.GF10302@sirena.org.uk> Content-Type: text/plain; charset="windows-1252" Content-Language: en-US Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/03/2018 06:26 AM, Mark Brown wrote: > On Fri, Aug 31, 2018 at 01:05:07PM -0500, Andrew F. Davis wrote: >> Leaving microphone bias off is a valid setting and even used in the DT >> binding document example. Add this setting here and document the same. >> Although it may not make much sense to enable a microphone here without >> any bias, it is a valid setting that can be chosen by DT and may be >> needed for some boards. > > If we really want to pay attention to something setting this up we'd > need to completely remove the widget - what the code is doing at the > minute is setting the voltage that the bias will go to when enabled, > there's still a widget for turning it on and off. There's some chance > that this will break existing boards. > Turning on bias is controlled separately, automatically in user-space in many cases, not based on the board. The DT needs to have a way to state that 0v is the needed bias on this board, without this you can not set 0v bias and 2v is chosen by default (which is IMHO should be 0v but that would change existing behavior so I won't touch that).