From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benoit Cousson Subject: Re: [PATCH v4 6/8] ASoC: compress: Add support for DAI multicodec Date: Thu, 03 Jul 2014 13:46:23 +0200 Message-ID: <53B5428F.9050100@baylibre.com> References: <1404200881-32253-1-git-send-email-bcousson@baylibre.com> <1404200881-32253-7-git-send-email-bcousson@baylibre.com> <20140701164134.GH2296@intel.com> <53B400DE.3040205@baylibre.com> <20140703064147.GK2296@intel.com> <53B539E8.1000301@baylibre.com> <53B53C6B.8020707@metafoo.de> <53B540EE.30009@baylibre.com> <53B541F0.1040105@metafoo.de> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Received: from mail-wi0-f171.google.com (mail-wi0-f171.google.com [209.85.212.171]) by alsa0.perex.cz (Postfix) with ESMTP id A6DDB2655ED for ; Thu, 3 Jul 2014 13:46:26 +0200 (CEST) Received: by mail-wi0-f171.google.com with SMTP id n15so11254497wiw.10 for ; Thu, 03 Jul 2014 04:46:26 -0700 (PDT) In-Reply-To: <53B541F0.1040105@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 , Vinod Koul , broonie@kernel.org Cc: misael.lopez@ti.com, lgirdwood@gmail.com, alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org On 03/07/2014 13:43, Lars-Peter Clausen wrote: > On 07/03/2014 01:39 PM, Benoit Cousson wrote: >> On 03/07/2014 13:20, Lars-Peter Clausen wrote: >>> On 07/03/2014 01:09 PM, Benoit Cousson wrote: >>>> On 03/07/2014 08:41, Vinod Koul wrote: >>>>> On Wed, Jul 02, 2014 at 02:53:50PM +0200, Benoit Cousson wrote: >>>>>>>> @@ -622,23 +633,33 @@ int soc_new_compress(struct = >>>>>>>> snd_soc_pcm_runtime >>>>>>>> *rtd, int num) >>>>>>>> { >>>>>>>> struct snd_soc_codec *codec =3D rtd->codec; >>>>>>>> struct snd_soc_platform *platform =3D rtd->platform; >>>>>>>> - struct snd_soc_dai *codec_dai =3D rtd->codec_dai; >>>>>>>> struct snd_soc_dai *cpu_dai =3D rtd->cpu_dai; >>>>>>>> struct snd_compr *compr; >>>>>>>> struct snd_pcm *be_pcm; >>>>>>>> char new_name[64]; >>>>>>>> - int ret =3D 0, direction =3D 0; >>>>>>>> - >>>>>>>> - /* check client and interface hw capabilities */ >>>>>>>> - snprintf(new_name, sizeof(new_name), "%s %s-%d", >>>>>>>> - rtd->dai_link->stream_name, codec_dai->name, num); >>>>>>>> - >>>>>>>> - if (codec_dai->driver->playback.channels_min) >>>>>>>> - direction =3D SND_COMPRESS_PLAYBACK; >>>>>>>> - else if (codec_dai->driver->capture.channels_min) >>>>>>>> - direction =3D SND_COMPRESS_CAPTURE; >>>>>>>> - else >>>>>>>> - return -EINVAL; >>>>>>>> + int i, ret =3D 0, direction =3D -1; >>>>>>>> + >>>>>>>> + for (i =3D 0; i < rtd->num_codecs; i++) { >>>>>>>> + struct snd_soc_dai *codec_dai =3D rtd->codec_dais[i]; >>>>>>>> + /* check client and interface hw capabilities */ >>>>>>>> + snprintf(new_name, sizeof(new_name), "%s %s-%d", >>>>>>>> + rtd->dai_link->stream_name, codec_dai->name, num); >>>>>>>> + >>>>>>>> + if (direction < 0) { >>>>>>>> + if (codec_dai->driver->playback.channels_min) >>>>>>>> + direction =3D SND_COMPRESS_PLAYBACK; >>>>>>>> + else if (codec_dai->driver->capture.channels_min) >>>>>>>> + direction =3D SND_COMPRESS_CAPTURE; >>>>>>> direction wont change with multiple codecs, so this loop makes no >>>>>>> sense >>>>>>> here. >>>>>>> For simplcity perhaps we can use cpu_dai? >>>>>>>> + else >>>>>>>> + return -EINVAL; >>>>>>>> + } else { >>>>>>> when will this get executed? You have initialized direction to -1 >>>>>>> and if >>>>>>> case is >>>>>>> always true. I think compiler will simply remove the below sinppet. >>>>>> >>>>>> direction is set to -1, then the first iteration will set it to the >>>>>> direction of the first codec_dai. The other iteration are just >>>>>> checking that there are all in the same direction and will fail >>>>>> otherwise. >>>>>> >>>>>>>> + if ((codec_dai->driver->playback.channels_min && >>>>>>>> + direction !=3D SND_COMPRESS_PLAYBACK) || >>>>>>>> + (codec_dai->driver->capture.channels_min && >>>>>>>> + direction !=3D SND_COMPRESS_CAPTURE)) >>>>>>> and what exactly are we trying to check here? >>>>>> >>>>>> That every codec_dai are in the same direction. >>>>>> >>>>>> If you think this is pointless since every DAI are always in the >>>>>> same direction, we can just remove it. >>>>> I think that will simplify it. we certainly dont expect different >>>>> direction, >>>>> right? >>>> >>>> Lars, Mark >>>> Any thought on that? Does that sound reasonable to you to use only the >>>> first >>>> codec_dai to figure out the direction? >>>> >>> >>> I guess it is ok. But I'm wondering if the direction shouldn't depend on >>> the CPU dai rather than the CODEC dai? E.g. it is possible to have a >>> CODEC with both playback and capture support in two dai_links, one for >>> capture, one for playback. The check above would create a >>> SND_COMPRESS_PLAYBACK stream in both cases. Even if the CPU dai only >>> supported capture in one of the cases. >> >> OK, I'll use the cpu_dai then. > = > Lets wait for Vinod's feedback on this first. He knows this code best = > and what the intentions are. Sure, but he was the first one to propose using that :-) >>>>>>> direction wont change with multiple codecs, so this loop makes no >>>>>>> sense >>>>>>> here. >>>>>>> For simplcity perhaps we can use cpu_dai? Regards, Benoit -- = Beno=EEt Cousson BayLibre Embedded Linux Technology Lab www.baylibre.com