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From: Bastien Curutchet <bastien.curutchet@bootlin.com>
To: Liam Girdwood <lgirdwood@gmail.com>,
	Mark Brown <broonie@kernel.org>,
	Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Peter Ujfalusi <peter.ujfalusi@gmail.com>,
	Jaroslav Kysela <perex@perex.cz>,
	Takashi Iwai <tiwai@suse.com>,
	Bastien Curutchet <bastien.curutchet@bootlin.com>
Cc: linux-sound@vger.kernel.org,
	devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	alsa-devel@alsa-project.org,
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
	herve.codina@bootlin.com,
	christophercordahi@nanometrics.ca
Subject: [PATCH v2 10/13] ASoC: ti: davinci-i2s: Link free-run mode to SND_SOC_DAIFMT_[GATED/CONT]
Date: Tue,  2 Apr 2024 09:12:10 +0200
Message-ID: <20240402071213.11671-11-bastien.curutchet@bootlin.com>
In-Reply-To: <20240402071213.11671-1-bastien.curutchet@bootlin.com>
References: <20240402071213.11671-1-bastien.curutchet@bootlin.com>
Precedence: bulk
MIME-Version: 1.0
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McBSP has free-running mode where serial clocks continue to run during
emulation halts. This mode is always enabled by the driver.

Set free-running mode when SND_SOC_DAIFMT_CONT is selected by DAI
format, unset it when SND_SOC_DAIFMT_GATED is selected.

Signed-off-by: Bastien Curutchet <bastien.curutchet@bootlin.com>
---
 sound/soc/ti/davinci-i2s.c | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/sound/soc/ti/davinci-i2s.c b/sound/soc/ti/davinci-i2s.c
index 82a0dfa07cec..7fb41987175b 100644
--- a/sound/soc/ti/davinci-i2s.c
+++ b/sound/soc/ti/davinci-i2s.c
@@ -280,6 +280,7 @@ static int davinci_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai,
 {
 	struct davinci_mcbsp_dev *dev = snd_soc_dai_get_drvdata(cpu_dai);
 	unsigned int pcr;
+	unsigned int spcr;
 	unsigned int srgr;
 	bool inv_fs = false;
 	/* Attention srgr is updated by hw_params! */
@@ -288,6 +289,23 @@ static int davinci_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai,
 		DAVINCI_MCBSP_SRGR_FWID(DEFAULT_BITPERSAMPLE - 1);
 
 	dev->fmt = fmt;
+
+	spcr = davinci_mcbsp_read_reg(dev, DAVINCI_MCBSP_SPCR_REG);
+	switch (fmt & SND_SOC_DAIFMT_CLOCK_MASK) {
+	case SND_SOC_DAIFMT_CONT:
+		spcr |= DAVINCI_MCBSP_SPCR_FREE;
+		dev_dbg(dev->dev, "Free-running mode ON\n");
+		break;
+	case SND_SOC_DAIFMT_GATED:
+		spcr &= ~DAVINCI_MCBSP_SPCR_FREE;
+		dev_dbg(dev->dev, "Free-running mode OFF\n");
+		break;
+	default:
+		dev_err(dev->dev, "Invalid clock gating\n");
+		return -EINVAL;
+	}
+	davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr);
+
 	/* set master/slave audio interface */
 	switch (fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
 	case SND_SOC_DAIFMT_BP_FP:
@@ -452,10 +470,10 @@ static int davinci_i2s_hw_params(struct snd_pcm_substream *substream,
 	/* general line settings */
 	spcr = davinci_mcbsp_read_reg(dev, DAVINCI_MCBSP_SPCR_REG);
 	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
-		spcr |= DAVINCI_MCBSP_SPCR_RINTM(3) | DAVINCI_MCBSP_SPCR_FREE;
+		spcr |= DAVINCI_MCBSP_SPCR_RINTM(3);
 		davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr);
 	} else {
-		spcr |= DAVINCI_MCBSP_SPCR_XINTM(3) | DAVINCI_MCBSP_SPCR_FREE;
+		spcr |= DAVINCI_MCBSP_SPCR_XINTM(3);
 		davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr);
 	}
 
-- 
2.44.0