Unverified Commit 1e112c35 authored by Peter Ujfalusi's avatar Peter Ujfalusi Committed by Mark Brown
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ASoC: ti: davinci-mcasp: Correct slot_width posed constraint 



The slot_width is a property for the bus while the constraint for
SNDRV_PCM_HW_PARAM_SAMPLE_BITS is for the in memory format.

Applying slot_width constraint to sample_bits works most of the time, but
it will blacklist valid formats in some cases.

With slot_width 24 we can support S24_3LE and S24_LE formats as they both
look the same on the bus, but a a 24 constraint on sample_bits would not
allow S24_LE as it is stored in 32bits in memory.

Implement a simple hw_rule function to allow all formats which require less
or equal number of bits on the bus as slot_width (if configured).

Signed-off-by: default avatarPeter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20190726064244.3762-2-peter.ujfalusi@ti.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 789e162a

sound/soc/ti/davinci-mcasp.c

+34 −9
Original line number Diff line number Diff line
@@ -1257,6 +1257,28 @@ static int davinci_mcasp_trigger(struct snd_pcm_substream *substream, 
	return ret;

}



static int davinci_mcasp_hw_rule_slot_width(struct snd_pcm_hw_params *params,

					    struct snd_pcm_hw_rule *rule)

{

	struct davinci_mcasp_ruledata *rd = rule->private;

	struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);

	struct snd_mask nfmt;

	int i, slot_width;



	snd_mask_none(&nfmt);

	slot_width = rd->mcasp->slot_width;



	for (i = 0; i <= SNDRV_PCM_FORMAT_LAST; i++) {

		if (snd_mask_test(fmt, i)) {

			if (snd_pcm_format_width(i) <= slot_width) {

				snd_mask_set(&nfmt, i);

			}

		}

	}



	return snd_mask_refine(fmt, &nfmt);

}



static const unsigned int davinci_mcasp_dai_rates[] = {

	8000, 11025, 16000, 22050, 32000, 44100, 48000, 64000,

	88200, 96000, 176400, 192000,
@@ -1378,7 +1400,7 @@ static int davinci_mcasp_startup(struct snd_pcm_substream *substream, 
	struct davinci_mcasp_ruledata *ruledata =

					&mcasp->ruledata[substream->stream];

	u32 max_channels = 0;

	int i, dir;

	int i, dir, ret;

	int tdm_slots = mcasp->tdm_slots;



	/* Do not allow more then one stream per direction */
@@ -1407,6 +1429,7 @@ static int davinci_mcasp_startup(struct snd_pcm_substream *substream, 
			max_channels++;

	}

	ruledata->serializers = max_channels;

	ruledata->mcasp = mcasp;

	max_channels *= tdm_slots;

	/*

	 * If the already active stream has less channels than the calculated
@@ -1432,20 +1455,22 @@ static int davinci_mcasp_startup(struct snd_pcm_substream *substream, 
				   0, SNDRV_PCM_HW_PARAM_CHANNELS,

				   &mcasp->chconstr[substream->stream]);



	if (mcasp->slot_width)

		snd_pcm_hw_constraint_minmax(substream->runtime,

					     SNDRV_PCM_HW_PARAM_SAMPLE_BITS,

					     8, mcasp->slot_width);

	if (mcasp->slot_width) {

		/* Only allow formats require <= slot_width bits on the bus */

		ret = snd_pcm_hw_rule_add(substream->runtime, 0,

					  SNDRV_PCM_HW_PARAM_FORMAT,

					  davinci_mcasp_hw_rule_slot_width,

					  ruledata,

					  SNDRV_PCM_HW_PARAM_FORMAT, -1);

		if (ret)

			return ret;

	}



	/*

	 * If we rely on implicit BCLK divider setting we should

	 * set constraints based on what we can provide.

	 */

	if (mcasp->bclk_master && mcasp->bclk_div == 0 && mcasp->sysclk_freq) {

		int ret;



		ruledata->mcasp = mcasp;



		ret = snd_pcm_hw_rule_add(substream->runtime, 0,

					  SNDRV_PCM_HW_PARAM_RATE,

					  davinci_mcasp_hw_rule_rate,

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