From 0ce918c9e070bf4fd17af0d76096ad184815bd79 Mon Sep 17 00:00:00 2001 From: "Andrew F. Davis" Date: Thu, 7 Dec 2017 09:38:56 -0600 Subject: [PATCH] ASoC: tlv320aic31xx: Reset registers during power up 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 Signed-off-by: Mark Brown --- 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 655c99d..858cb8b 100644 --- a/sound/soc/codecs/tlv320aic31xx.c +++ b/sound/soc/codecs/tlv320aic31xx.c @@ -1055,6 +1055,22 @@ static int aic31xx_regulator_event(struct notifier_block *nb, 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); + } + 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); @@ -1098,11 +1114,13 @@ 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 */ + ret = aic31xx_reset(aic31xx); + if (ret < 0) + dev_err(aic31xx->dev, "Could not reset device: %d\n", ret); + ret = regcache_sync(aic31xx->regmap); if (ret) { dev_err(codec->dev, -- 2.7.4