From 11277833ce8018ddd18925d2f85037bf02dcba63 Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Mon, 10 Nov 2014 12:32:16 +0200 Subject: [PATCH] ASoC: davinci-mcasp: Place constraint on number of channels In IIS (I2S, TDM, etc) mode the maximum number of allowed channels for either direction can be: number of serializers for the direction * tdm_slots. This constraint applicable for the first stream, while consequent stream should not have more channels then the first stream. Signed-off-by: Peter Ujfalusi Signed-off-by: Mark Brown --- sound/soc/davinci/davinci-mcasp.c | 60 +++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c index 10c264738a0b..10ae75e19d99 100644 --- a/sound/soc/davinci/davinci-mcasp.c +++ b/sound/soc/davinci/davinci-mcasp.c @@ -90,6 +90,9 @@ struct davinci_mcasp { bool dat_port; + /* Used for comstraint setting on the second stream */ + u32 channels; + #ifdef CONFIG_PM_SLEEP struct davinci_mcasp_context context; #endif @@ -811,6 +814,9 @@ static int davinci_mcasp_hw_params(struct snd_pcm_substream *substream, davinci_config_channel_size(mcasp, word_length); + if (mcasp->op_mode == DAVINCI_MCASP_IIS_MODE) + mcasp->channels = channels; + return 0; } @@ -839,7 +845,61 @@ static int davinci_mcasp_trigger(struct snd_pcm_substream *substream, return ret; } +static int davinci_mcasp_startup(struct snd_pcm_substream *substream, + struct snd_soc_dai *cpu_dai) +{ + struct davinci_mcasp *mcasp = snd_soc_dai_get_drvdata(cpu_dai); + u32 max_channels = 0; + int i, dir; + + if (mcasp->op_mode == DAVINCI_MCASP_DIT_MODE) + return 0; + + /* + * Limit the maximum allowed channels for the first stream: + * number of serializers for the direction * tdm slots per serializer + */ + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + dir = TX_MODE; + else + dir = RX_MODE; + + for (i = 0; i < mcasp->num_serializer; i++) { + if (mcasp->serial_dir[i] == dir) + max_channels++; + } + max_channels *= mcasp->tdm_slots; + /* + * If the already active stream has less channels than the calculated + * limnit based on the seirializers * tdm_slots, we need to use that as + * a constraint for the second stream. + * Otherwise (first stream or less allowed channels) we use the + * calculated constraint. + */ + if (mcasp->channels && mcasp->channels < max_channels) + max_channels = mcasp->channels; + + snd_pcm_hw_constraint_minmax(substream->runtime, + SNDRV_PCM_HW_PARAM_CHANNELS, + 2, max_channels); + return 0; +} + +static void davinci_mcasp_shutdown(struct snd_pcm_substream *substream, + struct snd_soc_dai *cpu_dai) +{ + struct davinci_mcasp *mcasp = snd_soc_dai_get_drvdata(cpu_dai); + + if (mcasp->op_mode == DAVINCI_MCASP_DIT_MODE) + return; + + if (!cpu_dai->active) + mcasp->channels = 0; +} + static const struct snd_soc_dai_ops davinci_mcasp_dai_ops = { + .startup = davinci_mcasp_startup, + .shutdown = davinci_mcasp_shutdown, .trigger = davinci_mcasp_trigger, .hw_params = davinci_mcasp_hw_params, .set_fmt = davinci_mcasp_set_dai_fmt, -- 2.34.1