From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jyri Sarha Subject: Re: [PATCH RFC 2/3] ASoC: hdmi-codec: add support for bclk_ratio Date: Mon, 25 Feb 2019 15:45:44 +0200 Message-ID: <520b346f-a874-790d-61ec-fb4ac67ad046@ti.com> References: <20190222212619.ghxly3eb6dx7p2ut@shell.armlinux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from fllv0015.ext.ti.com (fllv0015.ext.ti.com [198.47.19.141]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id E3086F89644 for ; Mon, 25 Feb 2019 14:45:50 +0100 (CET) In-Reply-To: Content-Language: en-GB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" To: Russell King , Sven Van Asbroeck , Mark Brown , Peter Ujfalusi Cc: Liam Girdwood , alsa-devel@alsa-project.org, Takashi Iwai List-Id: alsa-devel@alsa-project.org On 22/02/2019 23:27, Russell King wrote: > Some HDMI codecs need to know the relationship between the I2S bit clock > and the I2S word clock in order to correctly generate the CTS value for > audio clock recovery on the sink. > > Add support for this, but there are currently no callers of > snd_soc_dai_set_bclk_ratio(), we provide a default implementation that > uses the sample width to derive the ratio from the 8-bit aligned > sample size. This reflects the derivation that is in TDA998x, which > we are going to convert to use this new support. > > Signed-off-by: Russell King > --- > include/sound/hdmi-codec.h | 1 + > sound/soc/codecs/hdmi-codec.c | 45 +++++++++++++++++++++++++++++++++++++++++-- > 2 files changed, 44 insertions(+), 2 deletions(-) > > diff --git a/include/sound/hdmi-codec.h b/include/sound/hdmi-codec.h > index 9483c55f871b..0fca69880dc3 100644 > --- a/include/sound/hdmi-codec.h > +++ b/include/sound/hdmi-codec.h > @@ -42,6 +42,7 @@ struct hdmi_codec_daifmt { > unsigned int frame_clk_inv:1; > unsigned int bit_clk_master:1; > unsigned int frame_clk_master:1; > + unsigned int bclk_ratio; > }; > > /* > diff --git a/sound/soc/codecs/hdmi-codec.c b/sound/soc/codecs/hdmi-codec.c > index e5b6769b9797..d71a7e5a2231 100644 > --- a/sound/soc/codecs/hdmi-codec.c > +++ b/sound/soc/codecs/hdmi-codec.c > @@ -470,6 +470,7 @@ static int hdmi_codec_hw_params(struct snd_pcm_substream *substream, > struct snd_soc_dai *dai) > { > struct hdmi_codec_priv *hcp = snd_soc_dai_get_drvdata(dai); > + struct hdmi_codec_daifmt fmt; > struct hdmi_codec_params hp = { > .iec = { > .status = { 0 }, > @@ -520,8 +521,43 @@ static int hdmi_codec_hw_params(struct snd_pcm_substream *substream, > hp.sample_rate = params_rate(params); > hp.channels = params_channels(params); > > + fmt = hcp->daifmt[dai->id]; > + > + /* > + * If the .set_bclk_ratio() has not been called, default it > + * using the sample width for compatibility for TDA998x. > + * Rather than changing this, drivers should arrange to make > + * an appropriate call to snd_soc_dai_set_bclk_ratio(). > + */ > + if (fmt.bclk_ratio == 0) { > + switch (hp.sample_width) { > + case 16: > + fmt.bclk_ratio = 32; > + break; > + case 18: > + case 20: > + case 24: > + fmt.bclk_ratio = 48; > + break; AFAIK, this is not the usual choice for 18- or 20-bit samples. Usually, the bclk_ratio is set to the exact frame length required by the sample width without any padding. That is at least the case with tlv320aic3x-driver and 20-bit sample width. > + default: > + fmt.bclk_ratio = 64; > + break; > + } > + } > + > return hcp->hcd.ops->hw_params(dai->dev->parent, hcp->hcd.data, > - &hcp->daifmt[dai->id], &hp); > + &fmt, &hp); > +} > + > +static int hdmi_codec_set_bclk_ratio(struct snd_soc_dai *dai, > + unsigned int ratio) > +{ > + struct hdmi_codec_priv *hcp = snd_soc_dai_get_drvdata(dai); > + > + /* FIXME: some validation here would be good? */ > + hcp->daifmt[dai->id].bclk_ratio = ratio; > + > + return 0; > } > > static int hdmi_codec_set_fmt(struct snd_soc_dai *dai, > @@ -593,7 +629,11 @@ static int hdmi_codec_set_fmt(struct snd_soc_dai *dai, > } > } > > - hcp->daifmt[dai->id] = cf; > + hcp->daifmt[dai->id].fmt = cf.fmt; > + hcp->daifmt[dai->id].bit_clk_inv = cf.bit_clk_inv; > + hcp->daifmt[dai->id].frame_clk_inv = cf.frame_clk_inv; > + hcp->daifmt[dai->id].bit_clk_master = cf.bit_clk_master; > + hcp->daifmt[dai->id].frame_clk_master = cf.frame_clk_master; > > return ret; > } > @@ -615,6 +655,7 @@ static const struct snd_soc_dai_ops hdmi_dai_ops = { > .startup = hdmi_codec_startup, > .shutdown = hdmi_codec_shutdown, > .hw_params = hdmi_codec_hw_params, > + .set_bclk_ratio = hdmi_codec_set_bclk_ratio, > .set_fmt = hdmi_codec_set_fmt, > .digital_mute = hdmi_codec_digital_mute, > }; > -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki