From mboxrd@z Thu Jan 1 00:00:00 1970 From: Liam Girdwood Subject: Re: ASOC: For SND_SOC_DAIFMT_IB_IF what is invert baseed on? Date: Mon, 27 Oct 2008 13:47:27 +0000 Message-ID: <1225115247.28382.129.camel@dell-desktop.example.com> References: <4e090d470810250931k5e44a4cck3ad0186a2c47ec03@mail.gmail.com> <1225037126.28382.85.camel@dell-desktop.example.com> <4e090d470810262000t3d93538i3a71f5e5d042dd2f@mail.gmail.com> <1225104379.28382.104.camel@dell-desktop.example.com> <4e090d470810270624l5587d382o78330f737d709b8a@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from slimlogic.co.uk (slimlogic.co.uk [89.16.172.20]) by alsa0.perex.cz (Postfix) with ESMTP id 684F01037FA for ; Mon, 27 Oct 2008 14:47:28 +0100 (CET) In-Reply-To: <4e090d470810270624l5587d382o78330f737d709b8a@mail.gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: Richard Zhao Cc: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org On Mon, 2008-10-27 at 21:24 +0800, Richard Zhao wrote: > > Not quite, the clock is simply inverted compared to it's normal level. > > > > Well, what's the normal level? i2s LRCLK 's normal level is low for > frame start, but pcm's normal level is high for frame start. > > Different chips may have different meaning of "invert", because > "normal level" is not well defined. normal == standard. I2S spec is here :- http://www.nxp.com/acrobat_download/various/I2SBUS.pdf and is well defined. > SND_SOC_DAIFMT_NB_NF is a common > macro, so it cannot depend on any chip. So, could you please explain > in details what normal level and invert level of LRCLK/BCLK are in > i2s, pcm, left/right justified? > The wm8750 datasheet shows all this in diagrams :- http://www.wolfsonmicro.com/uploads/documents/WM8750.pdf It might be easier if you would send in your code so we can see what you are trying to accomplish. Liam