[PATCH 1/2] ASoc: fsl_micfil: explicitly clear software reset bit

From: Shengjiu Wang
Date: Sat May 07 2022 - 08:26:28 EST


SRES is self-cleared bit, but REG_MICFIL_CTRL1 is defined as
non volatile register, it still remain in regmap cache after set,
then every update of REG_MICFIL_CTRL1, software reset happens.
to avoid this, clear it explicitly.

Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
---
sound/soc/fsl/fsl_micfil.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/sound/soc/fsl/fsl_micfil.c b/sound/soc/fsl/fsl_micfil.c
index cd85c8714f97..2149fac0dcc6 100644
--- a/sound/soc/fsl/fsl_micfil.c
+++ b/sound/soc/fsl/fsl_micfil.c
@@ -179,6 +179,17 @@ static int fsl_micfil_reset(struct device *dev)
if (ret)
return ret;

+ /*
+ * SRES is self-cleared bit, but REG_MICFIL_CTRL1 is defined
+ * as non-volatile register, so SRES still remain in regmap
+ * cache after set, that every update of REG_MICFIL_CTRL1,
+ * software reset happens. so clear it explicitly.
+ */
+ ret = regmap_clear_bits(micfil->regmap, REG_MICFIL_CTRL1,
+ MICFIL_CTRL1_SRES);
+ if (ret)
+ return ret;
+
return 0;
}

--
2.17.1