Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752793AbeADTym (ORCPT + 1 other); Thu, 4 Jan 2018 14:54:42 -0500 Received: from mail-pl0-f68.google.com ([209.85.160.68]:42174 "EHLO mail-pl0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752109AbeADTyk (ORCPT ); Thu, 4 Jan 2018 14:54:40 -0500 X-Google-Smtp-Source: ACJfBov2sXS5ohEmq+D4eHKkKjjc+Eadza0VbBIiEvYhAWfLRPpBqC0DWVswZ+zpZ0EuHQKDxMD2fQ== Date: Thu, 4 Jan 2018 11:54:38 -0800 From: Matthias Kaehlcke To: Liam Girdwood , Mark Brown , Jaroslav Kysela , Takashi Iwai , Rob Herring , Mark Rutland Cc: alsa-devel@alsa-project.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Bhumika Goyal , Arnaud Pouliquen , huang lin , Brian Norris , Dylan Reid Subject: Re: [PATCH] ASoC: codecs: dmic: Use channel map for configs with a single mic Message-ID: <20180104195438.GA200397@google.com> References: <20180104194848.198941-1-mka@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180104194848.198941-1-mka@chromium.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: + Brian & Dylan El Thu, Jan 04, 2018 at 11:48:48AM -0800 Matthias Kaehlcke ha dit: > The DMIC DAI driver specifies a number of 1 to 8 channels for each DAI. > The actual number of mics can currently not be configured in the device > tree or audio glue, but is derived from the min/max channels of the CPU > and codec DAI. A typical CPU DAI has two or more channels, in consequence > a single mic is treated as a stereo/multi channel device, even though > only one channel carries audio data. > > This change adds the option to specify the number of used DMIC channels > in the device tree. If a single channel is used we export a channel map > that marks all unused channels as invalid to indicate userspace that the > capture device is mono. > > Signed-off-by: Matthias Kaehlcke > --- > Documentation/devicetree/bindings/sound/dmic.txt | 2 + > sound/soc/codecs/dmic.c | 72 +++++++++++++++++++++--- > 2 files changed, 65 insertions(+), 9 deletions(-) > > diff --git a/Documentation/devicetree/bindings/sound/dmic.txt b/Documentation/devicetree/bindings/sound/dmic.txt > index 54c8ef6498a8..f7bf65611453 100644 > --- a/Documentation/devicetree/bindings/sound/dmic.txt > +++ b/Documentation/devicetree/bindings/sound/dmic.txt > @@ -7,10 +7,12 @@ Required properties: > > Optional properties: > - dmicen-gpios: GPIO specifier for dmic to control start and stop > + - num-channels: Number of microphones on this DAI > > Example node: > > dmic_codec: dmic@0 { > compatible = "dmic-codec"; > dmicen-gpios = <&gpio4 3 GPIO_ACTIVE_HIGH>; > + num-channels = <1>; > }; > diff --git a/sound/soc/codecs/dmic.c b/sound/soc/codecs/dmic.c > index b88a1ee66f80..c705a25b138e 100644 > --- a/sound/soc/codecs/dmic.c > +++ b/sound/soc/codecs/dmic.c > @@ -29,24 +29,29 @@ > #include > #include > > +struct dmic { > + struct gpio_desc *gpio_en; > + int channels; > +}; > + > static int dmic_daiops_trigger(struct snd_pcm_substream *substream, > int cmd, struct snd_soc_dai *dai) > { > - struct gpio_desc *dmic_en = snd_soc_dai_get_drvdata(dai); > + struct dmic *dmic = snd_soc_dai_get_drvdata(dai); > > - if (!dmic_en) > + if (!dmic || !dmic->gpio_en) > return 0; > > switch (cmd) { > case SNDRV_PCM_TRIGGER_START: > case SNDRV_PCM_TRIGGER_RESUME: > case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: > - gpiod_set_value(dmic_en, 1); > + gpiod_set_value(dmic->gpio_en, 1); > break; > case SNDRV_PCM_TRIGGER_STOP: > case SNDRV_PCM_TRIGGER_SUSPEND: > case SNDRV_PCM_TRIGGER_PAUSE_PUSH: > - gpiod_set_value(dmic_en, 0); > + gpiod_set_value(dmic->gpio_en, 0); > break; > } > > @@ -57,6 +62,42 @@ static const struct snd_soc_dai_ops dmic_dai_ops = { > .trigger = dmic_daiops_trigger, > }; > > +const struct snd_pcm_chmap_elem dmic_chmaps_single[] = { > + { .channels = 1, > + .map = { SNDRV_CHMAP_MONO } }, > + { .channels = 2, > + .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_NA } }, > + { .channels = 4, > + .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_NA, > + SNDRV_CHMAP_NA, SNDRV_CHMAP_NA } }, > + { .channels = 6, > + .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_NA, > + SNDRV_CHMAP_NA, SNDRV_CHMAP_NA, > + SNDRV_CHMAP_NA, SNDRV_CHMAP_NA } }, > + { .channels = 8, > + .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_NA, > + SNDRV_CHMAP_NA, SNDRV_CHMAP_NA, > + SNDRV_CHMAP_NA, SNDRV_CHMAP_NA, > + SNDRV_CHMAP_NA, SNDRV_CHMAP_NA } }, > + { } > +}; > + > +static int dmic_pcm_new(struct snd_soc_pcm_runtime *rtd, > + struct snd_soc_dai *dai) > +{ > + struct dmic *dmic = snd_soc_dai_get_drvdata(dai); > + int err; > + > + if (dmic->channels == 1) { > + err = snd_pcm_add_chmap_ctls(rtd->pcm, SNDRV_PCM_STREAM_CAPTURE, > + dmic_chmaps_single, 8, 0, NULL); > + if (err < 0) > + return err; > + } > + > + return 0; > +} > + > static struct snd_soc_dai_driver dmic_dai = { > .name = "dmic-hifi", > .capture = { > @@ -69,18 +110,31 @@ static struct snd_soc_dai_driver dmic_dai = { > | SNDRV_PCM_FMTBIT_S16_LE, > }, > .ops = &dmic_dai_ops, > + .pcm_new = dmic_pcm_new, > }; > > static int dmic_codec_probe(struct snd_soc_codec *codec) > { > - struct gpio_desc *dmic_en; > + struct dmic *dmic; > + int err; > + u32 pval; > + > + dmic = devm_kzalloc(codec->dev, sizeof(*dmic), GFP_KERNEL); > + if (!dmic) > + return -ENOMEM; > > - dmic_en = devm_gpiod_get_optional(codec->dev, > + dmic->gpio_en = devm_gpiod_get_optional(codec->dev, > "dmicen", GPIOD_OUT_LOW); > - if (IS_ERR(dmic_en)) > - return PTR_ERR(dmic_en); > + if (IS_ERR(dmic->gpio_en)) > + return PTR_ERR(dmic->gpio_en); > + > + err = of_property_read_u32(codec->dev->of_node, "num-channels", &pval); > + if (!err) > + dmic->channels = (int)pval; > + else if (err != -ENOENT) > + return err; > > - snd_soc_codec_set_drvdata(codec, dmic_en); > + snd_soc_codec_set_drvdata(codec, dmic); > > return 0; > }