Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c392bec7 authored by Troy Kisky's avatar Troy Kisky Committed by Mark Brown
Browse files

ASoC: DaVinci: i2s toggle clock to complete reset 



Add toggle_clock function to complete i2s reset earlier.

Signed-off-by: default avatarTroy Kisky <troy.kisky@boundarydevices.com>
Signed-off-by: default avatarMark Brown <broonie@opensource.wolfsonmicro.com>
parent 35cf6358

sound/soc/davinci/davinci-i2s.c

+25 −6
Original line number Diff line number Diff line
@@ -104,6 +104,7 @@ static struct davinci_pcm_dma_params davinci_i2s_pcm_in = { 


struct davinci_mcbsp_dev {

	void __iomem			*base;

	u32				pcr;

	struct clk			*clk;

	struct davinci_pcm_dma_params	*dma_params[2];

};
@@ -119,17 +120,34 @@ static inline u32 davinci_mcbsp_read_reg(struct davinci_mcbsp_dev *dev, int reg) 
	return __raw_readl(dev->base + reg);

}



static void toggle_clock(struct davinci_mcbsp_dev *dev, int playback)

{

	u32 m = playback ? DAVINCI_MCBSP_PCR_CLKXP : DAVINCI_MCBSP_PCR_CLKRP;

	/* The clock needs to toggle to complete reset.

	 * So, fake it by toggling the clk polarity.

	 */

	davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_PCR_REG, dev->pcr ^ m);

	davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_PCR_REG, dev->pcr);

}



static void davinci_mcbsp_start(struct snd_pcm_substream *substream)

{

	struct snd_soc_pcm_runtime *rtd = substream->private_data;

	struct davinci_mcbsp_dev *dev = rtd->dai->cpu_dai->private_data;

	struct snd_soc_device *socdev = rtd->socdev;

	struct snd_soc_platform *platform = socdev->card->platform;

	int playback = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);

	u32 spcr;

	int ret;



	/* Start the sample generator and enable transmitter/receiver */

	u32 mask = playback ? DAVINCI_MCBSP_SPCR_XRST : DAVINCI_MCBSP_SPCR_RRST;

	spcr = davinci_mcbsp_read_reg(dev, DAVINCI_MCBSP_SPCR_REG);

	if (spcr & mask) {

		/* start off disabled */

		davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG,

				spcr & ~mask);

		toggle_clock(dev, playback);

	}

	/* Start the sample generator and enable transmitter/receiver */

	spcr |= DAVINCI_MCBSP_SPCR_GRST;

	davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr);
@@ -155,6 +173,7 @@ static void davinci_mcbsp_start(struct snd_pcm_substream *substream) 
		spcr = davinci_mcbsp_read_reg(dev, DAVINCI_MCBSP_SPCR_REG);

		spcr &= ~DAVINCI_MCBSP_SPCR_XRST;

		davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr);

		toggle_clock(dev, playback);



		/* Restart the DMA */

		if (platform->pcm_ops->trigger) {
@@ -188,15 +207,14 @@ static void davinci_mcbsp_stop(struct snd_pcm_substream *substream) 
	struct snd_soc_pcm_runtime *rtd = substream->private_data;

	struct davinci_mcbsp_dev *dev = rtd->dai->cpu_dai->private_data;

	u32 spcr;

	int playback = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);



	/* Reset transmitter/receiver and sample rate/frame sync generators */

	spcr = davinci_mcbsp_read_reg(dev, DAVINCI_MCBSP_SPCR_REG);

	spcr &= ~(DAVINCI_MCBSP_SPCR_GRST | DAVINCI_MCBSP_SPCR_FRST);

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)

		spcr &= ~DAVINCI_MCBSP_SPCR_XRST;

	else

		spcr &= ~DAVINCI_MCBSP_SPCR_RRST;

	spcr &= playback ? ~DAVINCI_MCBSP_SPCR_XRST : ~DAVINCI_MCBSP_SPCR_RRST;

	davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr);

	toggle_clock(dev, playback);

}



static int davinci_i2s_startup(struct snd_pcm_substream *substream,
@@ -334,6 +352,7 @@ static int davinci_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai, 
		return -EINVAL;

	}

	davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SRGR_REG, srgr);

	dev->pcr = pcr;

	davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_PCR_REG, pcr);

	davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_RCR_REG, rcr);

	davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_XCR_REG, xcr);