diff options
| -rw-r--r-- | firmware/drivers/audio/ak4537.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/firmware/drivers/audio/ak4537.c b/firmware/drivers/audio/ak4537.c index 67ce9e3ed9..3a014f7527 100644 --- a/firmware/drivers/audio/ak4537.c +++ b/firmware/drivers/audio/ak4537.c @@ -176,6 +176,12 @@ void audiohw_close(void) /* power down the DAC */ akc_clear(AK4537_PM2, PMDAC); + /* Let the common voltage fall down before powering down headphone amp, + or a pop noise will occur. The fall time depends on the capacitor value + connected with the MUTET pin and is 100k*C up to 250k*C. + For Samsung YH devices (4.7uF) a minimum time of 470ms is needed. */ + udelay(800000); + /* power down the headphone amp */ akc_set(AK4537_SIGSEL2, HPL | HPR); @@ -187,7 +193,6 @@ void audiohw_close(void) /* power down VCOM */ akc_clear(AK4537_PM1, PMVCM); - udelay(100000); akcodec_close(); /* target-specific */ } |