diff options
-rw-r--r-- | Documentation/sound/soc/index.rst | 1 | ||||
-rw-r--r-- | Documentation/sound/soc/pops-clicks.rst (renamed from Documentation/sound/alsa/soc/pops_clicks.txt) | 15 |
2 files changed, 10 insertions, 6 deletions
diff --git a/Documentation/sound/soc/index.rst b/Documentation/sound/soc/index.rst index 4ac3585..4dd6799 100644 --- a/Documentation/sound/soc/index.rst +++ b/Documentation/sound/soc/index.rst @@ -13,3 +13,4 @@ The documentation is spilt into the following sections:- dapm platform machine + pops-clicks diff --git a/Documentation/sound/alsa/soc/pops_clicks.txt b/Documentation/sound/soc/pops-clicks.rst index e1e74da..de7eb2a 100644 --- a/Documentation/sound/alsa/soc/pops_clicks.txt +++ b/Documentation/sound/soc/pops-clicks.rst @@ -1,3 +1,4 @@ +===================== Audio Pops and Clicks ===================== @@ -20,10 +21,11 @@ currently, however future audio codec hardware will have better pop and click suppression. Pops can be reduced within playback by powering the audio components in a specific order. This order is different for startup and shutdown and follows some basic rules:- +:: - Startup Order :- DAC --> Mixers --> Output PGA --> Digital Unmute - - Shutdown Order :- Digital Mute --> Output PGA --> Mixers --> DAC + Startup Order :- DAC --> Mixers --> Output PGA --> Digital Unmute + + Shutdown Order :- Digital Mute --> Output PGA --> Mixers --> DAC This assumes that the codec PCM output path from the DAC is via a mixer and then a PGA (programmable gain amplifier) before being output to the speakers. @@ -36,10 +38,11 @@ Capture artifacts are somewhat easier to get rid as we can delay activating the ADC until all the pops have occurred. This follows similar power rules to playback in that components are powered in a sequence depending upon stream startup or shutdown. +:: - Startup Order - Input PGA --> Mixers --> ADC - - Shutdown Order - ADC --> Mixers --> Input PGA + Startup Order - Input PGA --> Mixers --> ADC + + Shutdown Order - ADC --> Mixers --> Input PGA Zipper Noise |