[alsa-devel] asoc: s3c24xx+uda1380 - some questions

Vasily Khoruzhick anarsoul at gmail.com
Tue Jan 27 14:19:39 CET 2009

I'm trying to develop asoc driver for hp ipaq rx1950 (s3c24xx + uda1380).

1st question: where I can enable/disable uda1380 codec power? I need to 
control codec power for powersave reasons.

I tried to add custom power function call to uda1380_set_bias_level in 
uda1380.c (pointer to power function is stored in codec->private_data), as it 
done for uda134x codec, but after enable-disable-enable cycle (for example, 
after resuming from suspend) driver cannot communicate with codec anymore 
(i2c bus is always busy), only reloading i2c driver helps.

I suspect, power(0) is called in inappropriate moment, when i2c-transfer still 
is not finished.

2nd question: for some reason, driver does not produce any sound during first 
aplay invocation, only second and later aplay invocation driver produces 
sound. What can be the reason of this problem?

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