[alsa-devel] [PATCH] ALSA: ASoC: cs4720: use snd_soc_cache_sync()

Daniel Mack zonque at gmail.com
Tue Nov 22 17:04:46 CET 2011

On 11/22/2011 04:53 PM, Mark Brown wrote:
> On Tue, Nov 22, 2011 at 04:44:39PM +0100, Daniel Mack wrote:
>> The code is so simple that I'm starting to suspect
>> i2c_smbus_write_byte_data() is doing something very wrong, but I can't
>> trace it without a hardware I2C analyzer right now. The i2c-regmap
>> low-level implementation uses different access functions under the hood,
>> so maybe that's a regression.
> Could be, though I can't see any changes in the code here.  It might be
> that a change between SMBus and regmap at runtime is upsetting the
> device somehow but given that it's supposed to be coming back from a
> power on reset...

That should affect more codecs then, right?

$ git grep -l i2c_smbus_write sound/

>> We also think that the effect is actually rather new.
> Does reverting to the non-regmap soc-io.c help?

Is there a single commit we can revert on top of 3.2-git to test this?

>>> In any case, the patch is moving to factor code out in favour of core
>>> facilities so it's a good idea anyway.
>> Hmm, we should really care for the root cause, but maybe we can still
>> commit this thing, with a more appropriate commit log?
> I think so.

Ok, I'll repost with a better log then.

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