Re: [PATCH v3 0/2] clk: bcm2835: PCM clock improvements
From: Stefan Wahren
Date: Thu Jun 01 2017 - 05:38:31 EST
> Phil Elwell <phil@xxxxxxxxxxxxxxx> hat am 1. Juni 2017 um 11:10 geschrieben:
>
>
> The switch to using the upstream bcm2835_cprman clock driver caused a
> few problems for users of PCM (I2S) peripherals. Audio applications
> require accurate, stable clocks, and the cprman driver wasn't
> conservative enough in its choice of clock sources.
>
> These patches restrict the clock sources for the PCM peripheral in two
> ways: the first causes all possible sources except OSC and PLLD_PER
> to be ignored, while the second allows clocks to be specified as
> "low_jitter", causing the effects of fractional divisors to be taken
> into account when comparing potential clocks for accuracy. In practice,
> the combined effect of the two patches is to choose OSC as a source if
> an integer divisor can be used, otherwise PLLD_PER is chosen.
>
> Changes in v3:
> * Elimination of temporary variable from patch 2.
Acked-by: Stefan Wahren <stefan.wahren@xxxxxxxx>
still applies to the complete series