From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Hsu Subject: Re: [PATCH 1/2 v2] ASoC: nau8825: non-clock jack detection for power saving at standby Date: Fri, 20 May 2016 11:12:39 +0800 Message-ID: <573E80A7.50602@nuvoton.com> References: <1463131037-19220-1-git-send-email-KCHSU0@nuvoton.com> <20160513104841.GA22038@sirena.org.uk> <573926C5.70704@nuvoton.com> <20160518170549.GR8104@sirena.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: Received: from maillog.nuvoton.com (maillog.nuvoton.com [202.39.227.15]) by alsa0.perex.cz (Postfix) with ESMTP id C93B6260647 for ; Fri, 20 May 2016 05:12:43 +0200 (CEST) In-Reply-To: <20160518170549.GR8104@sirena.org.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Mark Brown Cc: AP MS30 Linux ALSA , "anatol.pomozov@gmail.com" , AC30 YHChuang , "lgirdwood@gmail.com" , "benzh@chromium.org" , AC30 CTLin0 , MS40 MHKuo , "yong.zhi@intel.com" List-Id: alsa-devel@alsa-project.org On 5/19/2016 1:05 AM, Mark Brown wrote: > On Mon, May 16, 2016 at 09:47:49AM +0800, John Hsu wrote: > > >> There is another patch is made by this patch. >> [PATCH 2/2] ASoC: nau8825: cross talk suppression measurement function >> > > I'm confused about what's going on here... if you're sending multiple > patches that need to be grouped together you should always send them all > together. If you're not sending a group of patches then you shouldn't > use numbering in the subject line. > > I understand. Thank you very much. >> Besides, please help to review the following patch for the DC offset >> issue. Thank you very much. >> [PATCH] ASoC: nau8825: apply BIQ to reduce recording signal DC offset >> > > This is hard to review since it's quite complex and doing things that > look like they might be using general purpose parts of the chip for > specialist purposes. > We find there is a DC offset issue when recording. For the issue, it needs a HPF in ADC to reduce the offset, but no such hardware circuit. Thus, the driver configures the biquard filter as HPF when headset connected. It is a must setup for the codec. This patch sets the coefficients A1, A2, B0, B1, and B3 in the biquad filter to make the HPF funciton.