Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753775AbbKXQFk (ORCPT ); Tue, 24 Nov 2015 11:05:40 -0500 Received: from mail-yk0-f182.google.com ([209.85.160.182]:34169 "EHLO mail-yk0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751842AbbKXQFi convert rfc822-to-8bit (ORCPT ); Tue, 24 Nov 2015 11:05:38 -0500 MIME-Version: 1.0 In-Reply-To: References: <1448014157-36526-1-git-send-email-raphael.poggi@avalun.com> <1448014157-36526-5-git-send-email-raphael.poggi@avalun.com> From: =?UTF-8?Q?Rapha=C3=ABl_Poggi?= Date: Tue, 24 Nov 2015 17:04:58 +0100 X-Google-Sender-Auth: eRl34KFX-VwSQyvVmy2cQwUXCRY Message-ID: Subject: Re: [alsa-devel] [PATCH 4/4] sound: codecs: pcm1792a: introduce channel side To: Michael Trimarchi Cc: perex@perex.cz, tiwai@suse.com, "devicetree@vger.kernel.org" , "alsa-devel@alsa-project.org" , LKML Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6979 Lines: 185 Hi, 2015-11-24 9:27 GMT+01:00 Michael Trimarchi : > Hi > > On Tue, Nov 24, 2015 at 9:21 AM, Raphaël Poggi wrote: >> Hi, >> >> 2015-11-21 10:37 GMT+01:00 Michael Trimarchi : >>> Hi >>> >>> On Fri, Nov 20, 2015 at 11:09 AM, Raphael Poggi wrote: >>>> From: Raphael Poggi >>>> >>>> Add possibility to choose the channel side using the device tree, >>>> and also modify it using alsa ctrl. >>>> >>>> Signed-off-by: Raphael Poggi >>>> --- >>>> sound/soc/codecs/pcm1792a.c | 46 +++++++++++++++++++++++++++++++++++++++++++++ >>>> 1 file changed, 46 insertions(+) >>>> >>>> diff --git a/sound/soc/codecs/pcm1792a.c b/sound/soc/codecs/pcm1792a.c >>>> index febaa48..005b679 100644 >>>> --- a/sound/soc/codecs/pcm1792a.c >>>> +++ b/sound/soc/codecs/pcm1792a.c >>>> @@ -65,6 +65,12 @@ static const struct reg_default pcm1792a_reg_defaults[] = { >>>> { PCM1792A_DEVICE_ID, 0x00 }, >>>> }; >>>> >>>> +enum __pcm1792_side { >>>> + STEREO, >>>> + MONORAL_LEFT, >>>> + MONORAL_RIGHT >>>> +}; >>>> + >>>> static bool pcm1792a_accessible_reg(struct device *dev, unsigned int reg) >>>> { >>>> return reg >= 0x10 && reg <= 0x17; >>>> @@ -83,6 +89,7 @@ struct pcm1792a_private { >>>> struct regmap *regmap; >>>> unsigned int format; >>>> unsigned int rate; >>>> + unsigned int side; >>>> }; >>>> >>>> static int pcm1792a_set_dai_fmt(struct snd_soc_dai *codec_dai, >>>> @@ -153,6 +160,13 @@ static int pcm1792a_hw_params(struct snd_pcm_substream *substream, >>>> ret = regmap_update_bits(priv->regmap, PCM1792A_FMT_CONTROL, >>>> PCM1792A_FMT_MASK | PCM1792A_ATLD_ENABLE, val); >>>> >>>> + if (priv->side == MONORAL_LEFT) >>>> + val = PCM1792A_CHANNEL_MONO_LEFT; >>>> + else if (priv->side == MONORAL_RIGHT) >>>> + val = PCM1792A_CHANNEL_MONO_RIGHT; >>>> + >>>> + regmap_update_bits(priv->regmap, PCM1792A_CHANNEL, PCM1792A_CHANNEL_MONO_MASK, val); >>>> + >>>> return ret; >>>> } >>>> >>>> @@ -222,10 +236,31 @@ static struct snd_soc_codec_driver soc_codec_dev_pcm1792a = { >>>> .num_dapm_routes = ARRAY_SIZE(pcm1792a_dapm_routes), >>>> }; >>>> >>>> +static int pcm1792a_of_init(struct spi_device *spi) >>>> +{ >>>> + int ret = 0; >>>> + struct pcm1792a_private *pcm1792a = dev_get_drvdata(&spi->dev); >>>> + const char *name; >>>> + struct device_node *np = spi->dev.of_node; >>>> + >>>> + name = of_get_property(np, "ti,side", NULL); >>>> + if (name) { >>>> + if (!strcmp(name, "left")) >>>> + pcm1792a->side = MONORAL_LEFT; >>>> + else >>>> + pcm1792a->side = MONORAL_RIGHT; >>>> + } >>>> + else >>>> + pcm1792a->side = STEREO; >>>> + >>>> + return ret; >>>> +} >>>> + >>>> static int pcm1792a_spi_probe(struct spi_device *spi) >>>> { >>>> struct pcm1792a_private *pcm1792a; >>>> int ret; >>>> + struct device_node *np = spi->dev.of_node; >>>> >>>> pcm1792a = devm_kzalloc(&spi->dev, sizeof(struct pcm1792a_private), >>>> GFP_KERNEL); >>>> @@ -241,6 +276,17 @@ static int pcm1792a_spi_probe(struct spi_device *spi) >>>> return ret; >>>> } >>>> >>>> + if (np) { >>>> + ret = pcm1792a_of_init(spi); >>>> + if (ret) >>>> + return ret; >>>> + } >>>> + >>>> + if (pcm1792a->side == MONORAL_LEFT) >>>> + regmap_update_bits(pcm1792a->regmap, PCM1792A_CHANNEL, PCM1792A_CHANNEL_MONO_MASK, PCM1792A_CHANNEL_MONO_LEFT); >>>> + else if (pcm1792a->side == MONORAL_RIGHT) >>>> + regmap_update_bits(pcm1792a->regmap, PCM1792A_CHANNEL, PCM1792A_CHANNEL_MONO_MASK, PCM1792A_CHANNEL_MONO_RIGHT); >>>> + >>> >>> Why this is a part of dts and not a part of mixer control? >>> >>> Michael >>> >> >> The "channel side" bindings should be used when the pcm7192a is used >> in monaural mode (which requires two DACs, both DACs operate in a >> balanced mode for one channel of audio input data). >> This is a hardware level design, it will never change at runtime. >> I feel that a device tree binding is more appropriate than a control. >> > > Well I know exactly why is used for, but I don't really know if it's > somenthing that should be > in dts. Do I want to do channel inversion? > > Michael > I am not sure to understand. You mean "What if I want to do channel inversion", right ? If so, we have two differents "problems", one at hardware level design because monaural mode requires two DACs, and an another one at software level "channel inversion". I have always thought that hardware description should be in dts, that's why I implement monaural mode using dts. Honestly, I don't know what is the best solution between "this is a hardware design, it should be in dts and shouldn't change" vs "this should be an alsa controler because we want extra features independent from hardware design" Raphaël >>>> return snd_soc_register_codec(&spi->dev, >>>> &soc_codec_dev_pcm1792a, &pcm1792a_dai, 1); >>>> } >>>> -- >>>> 2.1.0 >>>> >>>> _______________________________________________ >>>> Alsa-devel mailing list >>>> Alsa-devel@alsa-project.org >>>> http://mailman.alsa-project.org/mailman/listinfo/alsa-devel >>> >>> >>> >>> -- >>> | Michael Nazzareno Trimarchi Amarula Solutions BV | >>> | COO - Founder Cruquiuskade 47 | >>> | +31(0)851119172 Amsterdam 1018 AM NL | >>> | [`as] http://www.amarulasolutions.com | >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >>> the body of a message to majordomo@vger.kernel.org >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> Please read the FAQ at http://www.tux.org/lkml/ > > > > -- > | Michael Nazzareno Trimarchi Amarula Solutions BV | > | COO - Founder Cruquiuskade 47 | > | +31(0)851119172 Amsterdam 1018 AM NL | > | [`as] http://www.amarulasolutions.com | > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/