Re: handling voice calls in ALSA soc (on Droid 4)

From: Pavel Machek
Date: Tue Jun 12 2018 - 08:18:08 EST


Sebastian, would you have pointer to original Motorola sources you
used for inspiration?

> > With setup like that, how does userland tell kernel that the baseband
> > <-> microphone/speaker connection should be activated?
> Audio routing should be done as normal, and ideally the driver for the
> modem will be able to figure out if there's an active call or not. If
> userspace has to enable the input and output manually then you can set
> up SOC_DAPM_PIN_SWITCH()es as normal.

Modem talks AT commands, so the driver is in userspace for now.

I tried SOC_DAPM_PIN_SWITCH(), but it results in alsamixer oopsing, I
guess I'm doing something wrong.

Message from syslogd@devuan at Jun 12 13:51:31 ...
kernel:[ 743.678588] BUG: spinlock bad magic on CPU#1,

Message from syslogd@devuan at Jun 12 13:51:31 ...
kernel:[ 743.684417] lock: 0xede423a0, .magic: eee2a6a4, .owner:
<none>/-1, .owner_cpu: -287136604

I'm trying to understand how it is supposed to work, but has TODO's at
critical places. If there's better source of information, let me know.

Best regards,
(cesky, pictures)

Attachment: signature.asc
Description: Digital signature