From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jose Abreu Subject: Re: [PATCH 2/5 v4] drm/i2c/adv7511: Add audio support Date: Mon, 11 Apr 2016 12:32:41 +0100 Message-ID: <570B8B59.7000900@synopsys.com> References: <5707D249.5040707@metafoo.de> <5707D88A.3010400@synopsys.com> <57091999.4010906@metafoo.de> <570B6DF2.1080008@synopsys.com> <570B6F7B.2020906@metafoo.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from smtprelay.synopsys.com (us01smtprelay-2.synopsys.com [198.182.47.9]) by alsa0.perex.cz (Postfix) with ESMTP id 71A4226055E for ; Mon, 11 Apr 2016 13:32:55 +0200 (CEST) In-Reply-To: <570B6F7B.2020906@metafoo.de> 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: Lars-Peter Clausen , Jose Abreu , linux-snps-arc@lists.infradead.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, alsa-devel@alsa-project.org Cc: architt@codeaurora.org, airlied@linux.ie, Vineet.Gupta1@synopsys.com, Alexey.Brodkin@synopsys.com, CARLOS.PALMINHA@synopsys.com, lgirdwood@gmail.com, broonie@kernel.org, tiwai@suse.com List-Id: alsa-devel@alsa-project.org Hi Lars, On 11-04-2016 10:33, Lars-Peter Clausen wrote: > On 04/11/2016 11:27 AM, Jose Abreu wrote: >> Hi Lars, >> >> >> On 09-04-2016 16:02, Lars-Peter Clausen wrote: >>> On 04/08/2016 06:12 PM, Jose Abreu wrote: >>> [...] >>>>> [...] >>>>>> +- adi,enable-audio: If set the ADV7511 driver will register a codec interface >>>>>> + into ALSA SoC. >>>>> This is not a description of the hardware. >>>> Is this okay: "adi,enable-audio: Set this boolean parameter if ADV7511 >>>> transmitter routes audio signals" ? >>> I don't think we need this property. There is no problem with registering >>> the audio part unconditionally. As long as there is no connection we wont >>> create a sound card that is exposed to userspace. >>> >> This change was suggested by Laurent Pinchart and was introduced in v3. Quoting >> Laurent: >> "The idea is that enabling support for ADV7511 audio in the kernel isn't coupled >> with whether the system includes audio support. It would be confusing, and would >> also waste resources, to create a Linux sound device when no sound channel is >> routed on the board." > I wouldn't care too much about this at this point, the extra amount of > resources required for registering the CODEC (but not the sound card) is > just a few bytes (sizeof(struct snd_soc_codec)). > > Nevertheless what we should do is describe the hardware and from this > information infer whether there is a audio connection or not and if there is > none we might skip registering the CODEC. In my opinion this hardware > description should be modeled using of-graph, having a connection between > the SoC side and the adv7511 SPDIF or I2S port. > You mean something like this: sound_playback: sound_playback { compatible = "simple-audio-card"; [...] simple-audio-card,format = "i2s"; [...] } adv7511@xx { compatible = "adi,adv7511"; [...] ports { [...] /* Audio Output */ port@x { reg = ; endpoint { remote-endpoint = <&sound_playback>; } } } } ? Best regards, Jose Miguel Abreu