[PATCH v2 15/19] ASoC: tlv320aic31xx: Reset registers during power up

Andrew F. Davis
2017-11-29T21:32:56Z

Add a reset function that toggles the reset line if available or uses
the software reset command otherwise. Use this in power up to ensure the
registers are in a sane state. This is useful when the driver module
is reloaded, or after Kexec, warm-reboots, etc..

Signed-off-by: Andrew F. Davis <afd@ti.com>
---
sound/soc/codecs/tlv320aic31xx.c | 26 ++++++++++++++++++++++----
1 file changed, 22 insertions(+), 4 deletions(-)

diff --git a/sound/soc/codecs/tlv320aic31xx.c b/sound/soc/codecs/tlv320aic31xx.c
index b51c2777e8d1..77ae8f36a943 100644
--- a/sound/soc/codecs/tlv320aic31xx.c
+++ b/sound/soc/codecs/tlv320aic31xx.c
@@ -1031,6 +1031,24 @@ static int aic31xx_set_dai_sysclk(struct snd_soc_dai *codec_dai,
return 0;
}

+static int aic31xx_reset(struct aic31xx_priv *aic31xx)
+{
+ int ret = 0;
+
+ if (aic31xx->gpio_reset) {
+ gpiod_set_value(aic31xx->gpio_reset, 1);
+ ndelay(10); /* At least 10ns */
+ gpiod_set_value(aic31xx->gpio_reset, 0);
+ } else {
+ ret = regmap_write(aic31xx->regmap, AIC31XX_RESET, 1);
+ if (ret < 0)
+ dev_err(aic31xx->dev, "Could not reset device\n");
+ }
+ mdelay(1); /* At least 1ms */
+
+ return ret;
+}
+
static void aic31xx_clk_on(struct snd_soc_codec *codec)
{
struct aic31xx_priv *aic31xx = snd_soc_codec_get_drvdata(codec);
@@ -1074,11 +1092,11 @@ static int aic31xx_power_on(struct snd_soc_codec *codec)
if (ret)
return ret;

- if (aic31xx->gpio_reset) {
- gpiod_set_value(aic31xx->gpio_reset, 0);
- udelay(100);
- }
regcache_cache_only(aic31xx->regmap, false);
+
+ /* Reset device registers for a consistent power-on like state */
+ aic31xx_reset(aic31xx);
+
ret = regcache_sync(aic31xx->regmap);
if (ret) {
dev_err(codec->dev,
--
2.15.0