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From:   Shengjiu Wang <shengjiu.wang@nxp.com>
To:     nicoleotsuka@gmail.com, Xiubo.Lee@gmail.com, festevam@gmail.com,
        shengjiu.wang@gmail.com, lgirdwood@gmail.com, broonie@kernel.org,
        perex@perex.cz, tiwai@suse.com, alsa-devel@alsa-project.org
Cc:     linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: [PATCH v2] ASoC: fsl_asrc: Add initialization finishing check in runtime resume
Date:   Wed,  7 Sep 2022 11:01:55 +0800
Message-Id: <1662519715-21891-1-git-send-email-shengjiu.wang@nxp.com>
Precedence: bulk

If the initialization is not finished, then filling input data to
the FIFO may fail. So it is better to add initialization finishing
check in the runtime resume for suspend & resume case.

And consider the case of three instances working in parallel,
increase the retry times to 50 for more initialization time.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
---
changes in v2:
- update comments.

 sound/soc/fsl/fsl_asrc.c | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/sound/soc/fsl/fsl_asrc.c b/sound/soc/fsl/fsl_asrc.c
index aa5edf32d988..b394b762025d 100644
--- a/sound/soc/fsl/fsl_asrc.c
+++ b/sound/soc/fsl/fsl_asrc.c
@@ -20,6 +20,7 @@
 
 #define IDEAL_RATIO_DECIMAL_DEPTH 26
 #define DIVIDER_NUM  64
+#define INIT_TRY_NUM 50
 
 #define pair_err(fmt, ...) \
 	dev_err(&asrc->pdev->dev, "Pair %c: " fmt, 'A' + index, ##__VA_ARGS__)
@@ -579,7 +580,7 @@ static void fsl_asrc_start_pair(struct fsl_asrc_pair *pair)
 {
 	struct fsl_asrc *asrc = pair->asrc;
 	enum asrc_pair_index index = pair->index;
-	int reg, retry = 10, i;
+	int reg, retry = INIT_TRY_NUM, i;
 
 	/* Enable the current pair */
 	regmap_update_bits(asrc->regmap, REG_ASRCTR,
@@ -592,6 +593,10 @@ static void fsl_asrc_start_pair(struct fsl_asrc_pair *pair)
 		reg &= ASRCFG_INIRQi_MASK(index);
 	} while (!reg && --retry);
 
+	/* NOTE: Doesn't treat initialization timeout as error */
+	if (!retry)
+		dev_warn(&asrc->pdev->dev, "initialization isn't finished\n");
+
 	/* Make the input fifo to ASRC STALL level */
 	regmap_read(asrc->regmap, REG_ASRCNCR, &reg);
 	for (i = 0; i < pair->channels * 4; i++)
@@ -1257,6 +1262,7 @@ static int fsl_asrc_runtime_resume(struct device *dev)
 {
 	struct fsl_asrc *asrc = dev_get_drvdata(dev);
 	struct fsl_asrc_priv *asrc_priv = asrc->private;
+	int reg, retry = INIT_TRY_NUM;
 	int i, ret;
 	u32 asrctr;
 
@@ -1295,6 +1301,20 @@ static int fsl_asrc_runtime_resume(struct device *dev)
 	regmap_update_bits(asrc->regmap, REG_ASRCTR,
 			   ASRCTR_ASRCEi_ALL_MASK, asrctr);
 
+	/* Wait for status of initialization for every enabled pairs */
+	do {
+		udelay(5);
+		regmap_read(asrc->regmap, REG_ASRCFG, &reg);
+		reg = (reg >> ASRCFG_INIRQi_SHIFT(0)) & 0x7;
+	} while ((reg != ((asrctr >> ASRCTR_ASRCEi_SHIFT(0)) & 0x7)) && --retry);
+
+	/*
+	 * NOTE: Doesn't treat initialization timeout as error
+	 * Some of pair maybe success, then still can continue.
+	 */
+	if (!retry)
+		dev_warn(dev, "initialization isn't finished\n");
+
 	return 0;
 
 disable_asrck_clk:
-- 
2.34.1