[alsa-devel] [PATCH] ASoC: wm8962: Enable SYSCLK provisonally before fetching generated DSPCLK_DIV

Charles Keepax ckeepax at opensource.wolfsonmicro.com
Thu Dec 5 15:14:21 CET 2013

On Wed, Dec 04, 2013 at 05:22:16PM +0800, Nicolin Chen wrote:
> DSPCLK_DIV can be only generated correctly after enabling SYSCLK. But if the
> current bias_level hasn't reached SND_SOC_BIAS_ON, DAPM won't enable SYSCLK,
> which would cause the calculation result from DSPCLK_DIV invalid since bit
> DSPCLK_DIV will be finally turned to its true value after DAPM enables SYSCLK
> while the driver won't calculate it again for the current instance. In this
> circumstance, a playback which needs non-zero DSPCLK_DIV would be distorted
> due to unexpected clock frequency resulted from an invalid DSPCLK_DIV value.
> So this patch provisionally enables the SYSCLK to get a valid DSPCLK_DIV for
> calculation and then disables it afterward.

Acked-by: Charles Keepax <ckeepax at opensource.wolfsonmicro.com>

It feels like there should be a neater way to handle this, but I
can't really see what that might be right now. So I think this
looks fine for now and hopefully I can find some time to look at
it in more detail soon.


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