From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1753345AbbINGeP (ORCPT <rfc822;w@1wt.eu>);
	Mon, 14 Sep 2015 02:34:15 -0400
Received: from nasmtp01.atmel.com ([192.199.1.245]:14141 "EHLO
	DVREDG01.corp.atmel.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org
	with ESMTP id S1751239AbbINGeN (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Mon, 14 Sep 2015 02:34:13 -0400
Subject: Re: [PATCH 1/2] ASoC: atmel-classd: add the Audio Class D Amplifier
 code
To: Mark Brown <broonie@kernel.org>
References: <1441086101-15303-1-git-send-email-songjun.wu@atmel.com>
 <1441086101-15303-2-git-send-email-songjun.wu@atmel.com>
 <20150903113716.GU12027@sirena.org.uk> <55EC0AF5.8060403@atmel.com>
 <20150907162350.GV5313@sirena.org.uk> <55EEAC01.3080409@atmel.com>
 <20150908122322.GB9751@sirena.org.uk> <55EFA478.1000109@atmel.com>
 <20150909095245.GG9751@sirena.org.uk> <55F0EB68.9070800@atmel.com>
 <20150911103417.GF12027@sirena.org.uk>
CC: <nicolas.ferre@atmel.com>, <lgirdwood@gmail.com>, <perex@perex.cz>,
        <tiwai@suse.com>, <linux-kernel@vger.kernel.org>,
        <alsa-devel@alsa-project.org>, <robh+dt@kernel.org>,
        <pawel.moll@arm.com>, <mark.rutland@arm.com>,
        <ijc+devicetree@hellion.org.uk>, <galak@codeaurora.org>,
        <devicetree@vger.kernel.org>, <linux-arm-kernel@lists.infradead.org>
From: "Wu, Songjun" <songjun.wu@atmel.com>
Organization: ATMEL
Message-ID: <55F66A5A.7010502@atmel.com>
Date: Mon, 14 Sep 2015 14:34:02 +0800
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101
 Thunderbird/38.2.0
MIME-Version: 1.0
In-Reply-To: <20150911103417.GF12027@sirena.org.uk>
Content-Type: text/plain; charset="windows-1252"; format=flowed
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org



On 9/11/2015 18:34, Mark Brown wrote:
> On Thu, Sep 10, 2015 at 10:31:04AM +0800, Wu, Songjun wrote:
>> On 9/9/2015 17:52, Mark Brown wrote:
>
>>> Yes, that's what's going to end up happening but it's not how controls
>>> are expected to behave - applications will expect changing one control
>>> to leave others unaffected so it's better to return an error rather than
>>> change the other control.
>
>> If application change non EQ controls, the others will be unaffected. But
>> the classD IP can only supports one EQ control at once, these three EQ
>> controls point to the same register field, if application set a different EQ
>> control, the error occurs, there will be many errors, it's not very
>> reasonable to application. The best way I think is if application set one EQ
>> control, the other EQ controls will change to 0dB, it's also consistent with
>> fact.
>
> There's no really good solutions here - this is why my initial
> suggestion was to have a single enumerated control.
>
You are right, your suggestion is reasonable, to have a single 
enumerated control. The second version will be made and sent soon.