Commit 2924a998 authored by Nicolin Chen's avatar Nicolin Chen Committed by Mark Brown
Browse files

ASoC: fsl_ssi: Add monaural audio support for non-ac97 interface 



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: default avatarNicolin Chen <b42378@freescale.com>
Signed-off-by: default avatarMark Brown <broonie@linaro.org>
parent 3621dbbc

sound/soc/fsl/fsl_ssi.c

+12 −7
Original line number Diff line number Diff line
@@ -143,6 +143,7 @@ struct fsl_ssi_private { 
	bool ssi_on_imx;

	bool imx_ac97;

	bool use_dma;

	u8 i2s_mode;

	struct clk *clk;

	struct snd_dmaengine_dai_dma_data dma_params_tx;

	struct snd_dmaengine_dai_dma_data dma_params_rx;
@@ -354,14 +355,13 @@ static void fsl_ssi_setup_ac97(struct fsl_ssi_private *ssi_private) 
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
@@ -378,7 +378,7 @@ 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 |
@@ -508,6 +508,7 @@ 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);
@@ -537,6 +538,11 @@ 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;

}
@@ -649,14 +655,13 @@ 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,

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