Comment 4 for bug 1824259

This is actually a kernel bug, in Linux. The issue is the absence of platform data for this particular board in the snd_soc_rt5645 module.

The issue can be worked around by creating /etc/modprobe.d/hacksound.conf with the following contents:

# Invert jack detection (1) and use detection mode 2 (2).
options snd_soc_rt5645 quirk=0x21

This takes advantage of the "quirk" option for the module, added in https://github.com/torvalds/linux/commit/4999b0214b05a08b42bbafcb29a0b9c413002d3f, which allows overriding the platform data it usually just has built into it about how audio jacks are hooked up on particular systems.

It looks like this board needs special system info added to sound/soc/codecs/rt5645.c, keyed on DMI data. The platform data would look something like:

static const struct rt5645_platform_data lattepanda_platform_data = {
 .jd_mode = 2,
 .inv_jd1_1 = true
};

Here's the DMI data for the motherboard; it's a bit generic. I can provide other DMI data to match on if needed.

Base Board Information
        Manufacturer: AMI Corporation
        Product Name: Cherry Trail CR
        Version: Default string
        Serial Number: Default string
        Asset Tag: Default string
        Features:
                Board is a hosting board
                Board is replaceable
        Location In Chassis: Default string
        Chassis Handle: 0x0003
        Type: Motherboard
        Contained Object Handles: 0