Comment 447 for bug 1776563

Maybe it worked with kernel 4.19 with your distribution but touchpad didn't work for me since i only use vanilla kernels without patches.
Ubuntu patches i2c-amd-mp2 support, in older kernel series there was an older version that didn't work for many laptop users that needed to recompile the kernel without that module built in and add the support later, but maybe it works with A315-41 laptops.
In later ubuntu kernels series the i2c-amd-mp2 support is built as a module =m instead so it can stopped from loading, in 4.19 it's still compiled into the kernel =y for both x86_64 and i386 in the kernel config but in 5.0 it's compiled as a module =m for x86_64 but not at all for i386 (source https://kernel.ubuntu.com/~kernel-ppa/mainline).
If that patched support makes your touchpad work good with ubuntu then good for you but not everyone is a ubuntu user.
For vanilla kernels the touchpad support is supposed to land in mainline in kernel 5.2.

It's very easy for people using certain distributions to think that because something works that it's works for everyone, not taking into account the distributions extensive patching and fixes everywhere but also hardware variations.
I use vanilla kernels not patched ones.
I just tried a non patched 4.19 kernel with those options and it did boot, i was also able to get touchpad working with dkms i2c-amd-mp2, so things seems to work with 4.19 as well.
If your distribution use patched kernels you might have had some support with earlier kernels, not because of the linux kernel but rather your distributions patches, so kernel updates might be different with different distributions or if you use a vanilla kernel.

Battery draining, i don't have any drainage battery problems that i am aware of, yesterday i used my laptop for 3 hours on battery, working, looking some youtube, some video from hdd and 25-30minutes of compiling.
I think that the battery uptime is acceptable and i got almost 3h with 4.19 as well but then i didn't compile anything.
I got no idea how long the battery should last but 3h seems ok to me.
How fast do your battery drain?