Commit f430a27f authored by Peter Ujfalusi's avatar Peter Ujfalusi Committed by Liam Girdwood
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ASoC: tlv320dac33: Revisit the FIFO Mode1 handling 



Replace the hardwired latency definition with platform data
parameter, and simplify the nSample parameter calculation.

Signed-off-by: default avatarPeter Ujfalusi <peter.ujfalusi@nokia.com>
Acked-by: default avatarMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: default avatarLiam Girdwood <lrg@slimlogic.co.uk>
parent b93cc9f1

include/sound/tlv320dac33-plat.h

+1 −0
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 


struct tlv320dac33_platform_data {

	int power_gpio;

	int mode1_latency; /* latency caused by the i2c writes in us */

	int keep_bclk;	/* Keep the BCLK running in FIFO modes */

	u8 burst_bclkdiv;

};

sound/soc/codecs/tlv320dac33.c

+34 −37
Original line number Diff line number Diff line
@@ -49,8 +49,6 @@ 


#define NSAMPLE_MAX		5700



#define LATENCY_TIME_MS		20



#define MODE7_LTHR		10

#define MODE7_UTHR		(DAC33_BUFFER_SIZE_SAMPLES - 10)
@@ -107,6 +105,8 @@ struct tlv320dac33_priv { 
					 * this */

	enum dac33_fifo_modes fifo_mode;/* FIFO mode selection */

	unsigned int nsample;		/* burst read amount from host */

	int mode1_latency;		/* latency caused by the i2c writes in

					 * us */

	u8 burst_bclkdiv;		/* BCLK divider value in burst mode */

	unsigned int burst_rate;	/* Interface speed in Burst modes */
@@ -649,7 +649,7 @@ static inline void dac33_prefill_handler(struct tlv320dac33_priv *dac33) 
	switch (dac33->fifo_mode) {

	case DAC33_FIFO_MODE1:

		dac33_write16(codec, DAC33_NSAMPLE_MSB,

			DAC33_THRREG(dac33->nsample + dac33->alarm_threshold));

			DAC33_THRREG(dac33->nsample));



		/* Take the timestamps */

		spin_lock_irq(&dac33->lock);
@@ -798,6 +798,10 @@ static void dac33_shutdown(struct snd_pcm_substream *substream, 
	struct tlv320dac33_priv *dac33 = snd_soc_codec_get_drvdata(codec);



	dac33->substream = NULL;



	/* Reset the nSample restrictions */

	dac33->nsample_min = 0;

	dac33->nsample_max = NSAMPLE_MAX;

}



static int dac33_hw_params(struct snd_pcm_substream *substream,
@@ -1040,48 +1044,38 @@ static void dac33_calculate_times(struct snd_pcm_substream *substream) 
	struct snd_soc_device *socdev = rtd->socdev;

	struct snd_soc_codec *codec = socdev->card->codec;

	struct tlv320dac33_priv *dac33 = snd_soc_codec_get_drvdata(codec);

	unsigned int period_size = substream->runtime->period_size;

	unsigned int rate = substream->runtime->rate;

	unsigned int nsample_limit;



	/* In bypass mode we don't need to calculate */

	if (!dac33->fifo_mode)

		return;



	/* Number of samples (16bit, stereo) in one period */

	dac33->nsample_min = snd_pcm_lib_period_bytes(substream) / 4;



	/* Number of samples (16bit, stereo) in ALSA buffer */

	dac33->nsample_max = snd_pcm_lib_buffer_bytes(substream) / 4;

	/* Subtract one period from the total */

	dac33->nsample_max -= dac33->nsample_min;



	/* Number of samples for LATENCY_TIME_MS / 2 */

	dac33->alarm_threshold = substream->runtime->rate /

				 (1000 / (LATENCY_TIME_MS / 2));



	/* Find and fix up the lowest nsmaple limit */

	nsample_limit = substream->runtime->rate / (1000 / LATENCY_TIME_MS);



	if (dac33->nsample_min < nsample_limit)

		dac33->nsample_min = nsample_limit;



	if (dac33->nsample < dac33->nsample_min)

		dac33->nsample = dac33->nsample_min;



	switch (dac33->fifo_mode) {

	case DAC33_FIFO_MODE1:

		/* Number of samples under i2c latency */

		dac33->alarm_threshold = US_TO_SAMPLES(rate,

						dac33->mode1_latency);

		/* nSample time shall not be shorter than i2c latency */

		dac33->nsample_min = dac33->alarm_threshold;

		/*

	 * Find and fix up the highest nsmaple limit

	 * In order to not overflow the DAC33 buffer substract the

	 * alarm_threshold value from the size of the DAC33 buffer

		 * nSample should not be bigger than alsa buffer minus

		 * size of one period to avoid overruns

		 */

	nsample_limit = DAC33_BUFFER_SIZE_SAMPLES - dac33->alarm_threshold;



		dac33->nsample_max = substream->runtime->buffer_size -

					period_size;

		nsample_limit = DAC33_BUFFER_SIZE_SAMPLES -

				dac33->alarm_threshold;

		if (dac33->nsample_max > nsample_limit)

			dac33->nsample_max = nsample_limit;



		/* Correct the nSample if it is outside of the ranges */

		if (dac33->nsample < dac33->nsample_min)

			dac33->nsample = dac33->nsample_min;

		if (dac33->nsample > dac33->nsample_max)

			dac33->nsample = dac33->nsample_max;



	switch (dac33->fifo_mode) {

	case DAC33_FIFO_MODE1:

		dac33->mode1_us_burst = SAMPLES_TO_US(dac33->burst_rate,

						      dac33->nsample);

		dac33->t_stamp1 = 0;
@@ -1519,6 +1513,9 @@ static int __devinit dac33_i2c_probe(struct i2c_client *client, 
	/* Pre calculate the burst rate */

	dac33->burst_rate = BURST_BASEFREQ_HZ / dac33->burst_bclkdiv / 32;

	dac33->keep_bclk = pdata->keep_bclk;

	dac33->mode1_latency = pdata->mode1_latency;

	if (!dac33->mode1_latency)

		dac33->mode1_latency = 10000; /* 10ms */

	dac33->irq = client->irq;

	dac33->nsample = NSAMPLE_MAX;

	dac33->nsample_max = NSAMPLE_MAX;