From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Jackson Subject: Re: [PATCH v3 2/5] ASoC: dwc: Iterate over all channels Date: Mon, 22 Dec 2014 14:08:44 +0000 Message-ID: <549825EC.80505@arm.com> References: <67cea1f0a74c333ec2048c7796cda37302d45e95.1418826016.git.Andrew.Jackson@arm.com> <20141222135301.GQ17800@sirena.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from cam-smtp0.cambridge.arm.com (fw-tnat.cambridge.arm.com [217.140.96.140]) by alsa0.perex.cz (Postfix) with ESMTP id E3B43260583 for ; Mon, 22 Dec 2014 15:08:45 +0100 (CET) In-Reply-To: <20141222135301.GQ17800@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: "alsa-devel@alsa-project.org" , Lars-Peter Clausen , Arnd Bergmann , Takashi Iwai , "linux-kernel@vger.kernel.org" , Liviu Dudau , Liam Girdwood , Rajeev Kumar , "linux-arm-kernel@lists.infradead.org" List-Id: alsa-devel@alsa-project.org On 12/22/14 13:53, Mark Brown wrote: > On Fri, Dec 19, 2014 at 04:18:06PM +0000, Andrew Jackson wrote: > >> The Designware core can be configured with up to four stereo channels. >> Each stereo channel is individually configured so, when the driver's >> hw_params call is made, each requested stereo channel has to be >> programmed. > > This is quite unclear to someone who doesn't know the hardware, is this > a bug fix or a new feature? It looks like it's a fix... > It is a fix. In the Designware core, each stereo channel is configured individually. So, when hw_params is called to configure N channels, N/2 stereo channels need to be configured in the core. The existing code doesn't do this and will only configure the highest numbered channel. Andrew