-----Original Message----- From: Mark Brown [mailto:broonie@kernel.org] Sent: Friday, March 14, 2014 4:43 AM To: Takashi Iwai Cc: Lars-Peter Clausen; Bard Liao; Oder Chiou; alsa-devel@alsa-project.org; lgirdwood@gmail.com; Gustaw Lewandowski; Flove Subject: Re: [alsa-devel] [PATCH v5] ASoC: add RT286 CODEC driver
On Thu, Mar 13, 2014 at 09:04:49PM +0100, Takashi Iwai wrote:
Mark Brown wrote:
We don't really *need* the cache, it just makes it easier to do resume and gives a bit of a performance boost.
Well, the caching isn't just a bit. Without caching, you'd have to whip the sound hardware powered up/down at each time querying the current mixer value.
Realistically most hardware can't actually do that - there's a couple of the idle_bias_off devices that have built in LDOs which can but it's relatively unusual to be able to remove enough power to loose register I/O (and in any case you wind up needing to cache the values per control or something in order to do system suspend).
Mark,
What's your suggestion of the I/O part of rt286 codec driver? Can I keep using regmap without using its cache? Or it is better not using regmap in this driver?
Thanks.
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