On 2019-01-26 14:17, Dimitris Papavasiliou wrote: > Some boards, such as the HiFiBerry DAC+ Pro, use a pair of external > oscillators, to generate 44.1 or 48kHz multiples and are forced to > resort to hacks [1] in order to support 24-bit data without ending up > with fractional dividers. This patch allows the machine driver to use > 32-bit frames for 24-bit data to avoid such issues. > > Although the datasheet (p. 15) seems to suggest that only a handful > of ratios are supported, it's not very explicit about it, so we allow > the full range of values supported by the underlying register in the > callback, to avoid needlessly rejecting potentially usable > configurations. > > [1] http://mailman.alsa-project.org/pipermail/alsa-devel/2018-December/143442.html > > Signed-off-by: Dimitris Papavasiliou <dpapavas@xxxxxxxxx> > --- > > Notes: > This is essentially the same patch submitted previously as an RFC[1]. > It has been split in two, in order to separate the set_bclk_ratio > implementation from the clocking calculation fix and some conservative > checking has been added to the argument of the callback. > > [1] http://mailman.alsa-project.org/pipermail/alsa-devel/2019-January/144213.html > > sound/soc/codecs/pcm512x.c | 28 ++++++++++++++++++++++++---- > 1 file changed, 24 insertions(+), 4 deletions(-) > > diff --git a/sound/soc/codecs/pcm512x.c b/sound/soc/codecs/pcm512x.c > index 6cb1653be804..b63d9392bae3 100644 > --- a/sound/soc/codecs/pcm512x.c > +++ b/sound/soc/codecs/pcm512x.c > @@ -55,6 +55,7 @@ struct pcm512x_priv { > unsigned long overclock_dsp; > int mute; > struct mutex mutex; > + unsigned int bclk_ratio; > }; > > /* > @@ -915,10 +916,15 @@ static int pcm512x_set_dividers(struct snd_soc_dai *dai, > int fssp; > int gpio; > > - lrclk_div = snd_soc_params_to_frame_size(params); > - if (lrclk_div == 0) { > - dev_err(dev, "No LRCLK?\n"); > - return -EINVAL; > + if (pcm512x->bclk_ratio > 0) { > + lrclk_div = pcm512x->bclk_ratio; > + } else { > + lrclk_div = snd_soc_params_to_frame_size(params); > + > + if (lrclk_div == 0) { > + dev_err(dev, "No LRCLK?\n"); > + return -EINVAL; > + } > } > > if (!pcm512x->pll_out) { > @@ -1383,6 +1389,19 @@ static int pcm512x_set_fmt(struct snd_soc_dai *dai, unsigned int fmt) > return 0; > } > > +static int pcm512x_set_bclk_ratio(struct snd_soc_dai *dai, unsigned int ratio) > +{ > + struct snd_soc_component *component = dai->component; > + struct pcm512x_priv *pcm512x = snd_soc_component_get_drvdata(component); > + > + if (ratio > 256) > + return -EINVAL; ratio == 0 should also generate -EINVAL. Cheers, Peter > + > + pcm512x->bclk_ratio = ratio; > + > + return 0; > +} > + > static int pcm512x_digital_mute(struct snd_soc_dai *dai, int mute) > { > struct snd_soc_component *component = dai->component; > @@ -1438,6 +1457,7 @@ static const struct snd_soc_dai_ops pcm512x_dai_ops = { > .hw_params = pcm512x_hw_params, > .set_fmt = pcm512x_set_fmt, > .digital_mute = pcm512x_digital_mute, > + .set_bclk_ratio = pcm512x_set_bclk_ratio, > }; > > static struct snd_soc_dai_driver pcm512x_dai = { > _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
