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This is saying that the machine driver should disable jack detection over suspend and restart it during resume. The machine driver should suspend before the rest of the card which should mean that the CODEC gets powered off then. The core can't tell if jack detection is supposed to work over suspend, it is a standard wake event on systems like phones, but it sounds like on this system the power gets removed from the device so that can't work.

Sorry, I don't understand what you are trying to say here. My intention is to find a way to have sound working when suspending/resuming with jack inserted by not fudging the jack in the machine driver but fixing it in the CODEC.

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I don't understand why that would be expected to help? The main effect of keeping the bias on all the time would be to consume more power.

I don't fully understand the whole bias thing (I did try hard to understand it from the code), but in this specific instance it helps for suspending the CODEC. If idle_bias_on is true then idle_bias_off will be false, that would mean that during suspend (with jack inserted) in snd_soc_suspend() in switch (snd_soc_dapm_get_bias_level(dapm)) the flow goes in case SND_SOC_BIAS_STANDBY and since dapm->idle_bias_off is false it doesn't break from the case but falls through to SND_SOC_BIAS_OFF case which in turn calls the CODEC component's suspend callback.

The reason the sound stops working with jack inserted is that the CODEC suspend callback never gets called. It only gets called when the jack is not inserted.

Hi Postevca, I just reproduced the bug on my side. You are right that when jack inserted, the codec driver will never enter SND_SOC_BIAS_OFF or suspend or resume. This makes sense because the codec needs micbias power to detect button. Problem is that ALSA or dapm thought the codec power is on during suspend, but the system power is turned off and the registers are reset. The system power is controlled by EC and neither dapm or codec driver can do anything about it. The system power is just turned off.

Disabling the jack detection before suspend is ok because the system stops working during suspend anyway. Maybe a detailed comment is needed to explain why?