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authorPeter Ujfalusi <peter.ujfalusi@nokia.com>2010-07-28 15:26:54 +0300
committerLiam Girdwood <lrg@slimlogic.co.uk>2010-07-29 10:21:04 +0100
commitf430a27f05d42d26d3e438aa262a92565170573f (patch)
treef448771488ceeda1aa3488d166d2d9a4302dc2b8
parentb93cc9f19bade9e9ddd41958352168dc0d266f48 (diff)
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: Peter Ujfalusi <peter.ujfalusi@nokia.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
-rw-r--r--include/sound/tlv320dac33-plat.h1
-rw-r--r--sound/soc/codecs/tlv320dac33.c71
2 files changed, 35 insertions, 37 deletions
diff --git a/include/sound/tlv320dac33-plat.h b/include/sound/tlv320dac33-plat.h
index 3f428d53195b..1aa7bdbc208c 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 2fa946ce23a2..ced6fbbc9d91 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;