The normal mode of SSI allows it to send/receive data to/from the first
slot of each period. So we can use this normal mode to trick I2S signal
by puting/getting data to/from the first slot only (the left channel)
so as to support monaural audio playback and recording.
Signed-off-by: Nicolin Chen <b42...@freescale.com>
---
Changelog
v2:
* Moved i2s_mode to ssi_private so that we can save and retore it as needed
* And dropped the horrible static thing.
sound/soc/fsl/fsl_ssi.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)
diff --git a/sound/soc/fsl/fsl_ssi.c b/sound/soc/fsl/fsl_ssi.c
index f43be6d..cba5c4d 100644
--- a/sound/soc/fsl/fsl_ssi.c
+++ b/sound/soc/fsl/fsl_ssi.c
@@ -144,6 +144,7 @@ struct fsl_ssi_private {
bool imx_ac97;
bool use_dma;
bool use_dual_fifo;
+ u8 i2s_mode;
struct clk *clk;
struct snd_dmaengine_dai_dma_data dma_params_tx;
struct snd_dmaengine_dai_dma_data dma_params_rx;
@@ -325,14 +326,13 @@ static irqreturn_t fsl_ssi_isr(int irq, void *dev_id)
static int fsl_ssi_setup(struct fsl_ssi_private *ssi_private)
{
struct ccsr_ssi __iomem *ssi = ssi_private->ssi;
- u8 i2s_mode;
u8 wm;
int synchronous = ssi_private->cpu_dai_drv.symmetric_rates;
if (ssi_private->imx_ac97)
- i2s_mode = CCSR_SSI_SCR_I2S_MODE_NORMAL | CCSR_SSI_SCR_NET;
+ ssi_private->i2s_mode = CCSR_SSI_SCR_I2S_MODE_NORMAL |
CCSR_SSI_SCR_NET;
else
- i2s_mode = CCSR_SSI_SCR_I2S_MODE_SLAVE;
+ ssi_private->i2s_mode = CCSR_SSI_SCR_I2S_MODE_SLAVE;
/*
* Section 16.5 of the MPC8610 reference manual says that the SSI needs
@@ -349,7 +349,7 @@ static int fsl_ssi_setup(struct fsl_ssi_private
*ssi_private)
write_ssi_mask(&ssi->scr,
CCSR_SSI_SCR_I2S_MODE_MASK | CCSR_SSI_SCR_SYN,
CCSR_SSI_SCR_TFR_CLK_DIS |
- i2s_mode |
+ ssi_private->i2s_mode |
(synchronous ? CCSR_SSI_SCR_SYN : 0));
write_ssi(CCSR_SSI_STCR_TXBIT0 | CCSR_SSI_STCR_TFEN0 |
@@ -517,6 +517,7 @@ static int fsl_ssi_hw_params(struct snd_pcm_substream
*substream,
{
struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(cpu_dai);
struct ccsr_ssi __iomem *ssi = ssi_private->ssi;
+ unsigned int channels = params_channels(hw_params);
unsigned int sample_size =
snd_pcm_format_width(params_format(hw_params));
u32 wl = CCSR_SSI_SxCCR_WL(sample_size);
@@ -546,6 +547,11 @@ static int fsl_ssi_hw_params(struct snd_pcm_substream
*substream,
else
write_ssi_mask(&ssi->srccr, CCSR_SSI_SxCCR_WL_MASK, wl);
+ if (!ssi_private->imx_ac97)
+ write_ssi_mask(&ssi->scr,
+ CCSR_SSI_SCR_NET | CCSR_SSI_SCR_I2S_MODE_MASK,
+ channels == 1 ? 0 : ssi_private->i2s_mode);
+
return 0;
}
@@ -658,14 +664,13 @@ static const struct snd_soc_dai_ops fsl_ssi_dai_ops = {
static struct snd_soc_dai_driver fsl_ssi_dai_template = {
.probe = fsl_ssi_dai_probe,
.playback = {
- /* The SSI does not support monaural audio. */
- .channels_min = 2,
+ .channels_min = 1,
.channels_max = 2,
.rates = FSLSSI_I2S_RATES,
.formats = FSLSSI_I2S_FORMATS,
},
.capture = {
- .channels_min = 2,
+ .channels_min = 1,
.channels_max = 2,
.rates = FSLSSI_I2S_RATES,
.formats = FSLSSI_I2S_FORMATS,
--
1.8.4
--
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