lkml.org 
[lkml]   [2019]   [Sep]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] SoC: simple-card-utils: set 0Hz to sysclk when shutdown

Hi Katsuhiro

> >> Bad scenario as follows (mclk-fs = 256):
> >> - Initialize sysclk by correct value (Ex. 12.288MHz)
> >> - Codec set constraints of PCM rate by sysclk
> >> 48kHz (1/256), 32kHz (1/384), 24kHz (1/512)
> >> - Play 48kHz sound, it's acceptable
> >> - Sysclk is not changed
> >>
> >> - Play 32kHz sound, it's acceptable
> >> - Set sysclk to 8.192MHz (= fs * mclk-fs = 32k * 256)
> >> - Codec set constraints of PCM rate by sysclk
> >> 32kHz (1/256), 21.33kHz (1/384), 16kHz (1/512)
> >>
> >> - Play 48kHz again, but it's NOT acceptable because constraints
> >> do not allow 48kHz
(snip)
> Ah, sorry for confusing. It's not either. hw_params() of machine
> driver has been called even if constraints don't have a requested
> PCM rate. But it's not expected.
>
> For example, if constraints are 32k, 21.33k, 16k, hw_params() will
> be called with 32k when an user requests to play 48k sounds.

Oh, I see.
Thank you for explaining.

Thank you for your help !!
Best regards
---
Kuninori Morimoto

\
 
 \ /
  Last update: 2019-09-09 05:55    [W:0.030 / U:3.260 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site