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ASoC: Fix non-networked I2S mode for PXA SSP
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Two issues are fixed here:

 - I2S transmits the left frame with the clock low but I don't seem to
   get LRCLK out without SFRMDLY being set so invert SFRMP and set a
   delay.
 - I2S has a clock cycle prior to the first data byte in each channel
   so we need to delay the data by one cycle.

Tested-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
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Mark Brown committed Mar 14, 2009
1 parent 72d7466 commit 0ce36c5
Showing 1 changed file with 14 additions and 5 deletions.
19 changes: 14 additions & 5 deletions sound/soc/pxa/pxa-ssp.c
Original file line number Diff line number Diff line change
@@ -1,4 +1,3 @@
#define DEBUG
/*
* pxa-ssp.c -- ALSA Soc Audio Layer
*
Expand Down Expand Up @@ -561,14 +560,15 @@ static int pxa_ssp_set_dai_fmt(struct snd_soc_dai *cpu_dai,
sscr0 |= SSCR0_PSP;
sscr1 |= SSCR1_RWOT | SSCR1_TRAIL;

/* See hw_params() */
switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
case SND_SOC_DAIFMT_NB_NF:
sspsp |= SSPSP_SFRMP;
break;
case SND_SOC_DAIFMT_NB_IF:
sspsp |= SSPSP_SFRMP;
break;
case SND_SOC_DAIFMT_IB_IF:
sspsp |= SSPSP_SFRMP | SSPSP_SCMODE(3);
sspsp |= SSPSP_SCMODE(3);
break;
default:
return -EINVAL;
Expand Down Expand Up @@ -691,8 +691,17 @@ static int pxa_ssp_hw_params(struct snd_pcm_substream *substream,
#else
return -EINVAL;
#endif
} else
sspsp |= SSPSP_SFRMWDTH(width);
} else {
/* The frame width is the width the LRCLK is
* asserted for; the delay is expressed in
* half cycle units. We need the extra cycle
* because the data starts clocking out one BCLK
* after LRCLK changes polarity.
*/
sspsp |= SSPSP_SFRMWDTH(width + 1);
sspsp |= SSPSP_SFRMDLY((width + 1) * 2);
sspsp |= SSPSP_DMYSTRT(1);
}

ssp_write_reg(ssp, SSPSP, sspsp);
break;
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