Replace the hardwired latency definition with platform data parameter, and simplify the nSample parameter calculation.
Signed-off-by: Peter Ujfalusi peter.ujfalusi@nokia.com --- include/sound/tlv320dac33-plat.h | 1 + sound/soc/codecs/tlv320dac33.c | 71 ++++++++++++++++++-------------------- 2 files changed, 35 insertions(+), 37 deletions(-)
diff --git a/include/sound/tlv320dac33-plat.h b/include/sound/tlv320dac33-plat.h index 3f428d5..1aa7bdb 100644 --- a/include/sound/tlv320dac33-plat.h +++ b/include/sound/tlv320dac33-plat.h @@ -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; }; diff --git a/sound/soc/codecs/tlv320dac33.c b/sound/soc/codecs/tlv320dac33.c index 2fa946c..ced6fbb 100644 --- a/sound/soc/codecs/tlv320dac33.c +++ b/sound/soc/codecs/tlv320dac33.c @@ -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; - - /* - * 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_limit = DAC33_BUFFER_SIZE_SAMPLES - dac33->alarm_threshold; - - if (dac33->nsample_max > nsample_limit) - dac33->nsample_max = nsample_limit; - - if (dac33->nsample > dac33->nsample_max) - dac33->nsample = dac33->nsample_max; - 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; + /* + * nSample should not be bigger than alsa buffer minus + * size of one period to avoid overruns + */ + 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; + 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;