8bitdo pro 2 hall joysticks calibration issue

8bitdo pro 2 gamepad with hall effect joysticks has an issue that after pressing the left stick it extends (recalibrates) it's value range beyond the range in the unpressed state, so (in my case) ultimate UP (forward) direction does not register as 100%, so e.g. running mode in games becomes unreachable with the extreme stick position (until you push it). There's an undocumented firmware recalibration mode: https://www.reddit.com/r/8bitdo/comments/1dtkoqx/sticks_are_not_aligned_anyway_to_calibrate_this/

  From 8bitdo support about the Pro 2: 
  
  L1+R1+SELECT Hold 10sec start calibration
  
  Rotate both joysticks 3turns *Simultaneously clockwise
  
  Fully press both triggers 3times Press all combination keys again to complete the calibration
  
  Turn-off the controller then turn on again
 

Fedora drivers

Install rpm-fusion package. Install mesa...freeworld drivers.

Transcoding with intel quicksync (qsv) h264 -> hevc

Convert on hardware from h264 to h264 full hd, also compress audio to AAC to make a common .mp4 file.

#!/bin/env bash
# usage: enc.sh <source_file> <quality, e.g. 25, 1..51>
# https://trac.ffmpeg.org/wiki/Hardware/QuickSync
# accepts h264 and transcodes on hardware, tested.
ffmpeg -hwaccel qsv -c:v h264_qsv -i "$1" -init_hw_device qsv:hw -vf 'scale_qsv=1920:1080' -c:a aac -b:a 192K -c:v h264_qsv -global_quality:v $2 -preset:v 1 -profile:v 77 "$1-h264-aac-qsv-1080p-$2.mp4"

Convert to hevc/h265:

#!/bin/env bash
# usage: enc.sh <source_file> <quality, e.g. 25, 1..51>
# https://trac.ffmpeg.org/wiki/Hardware/QuickSync
# accepts h264 and transcodes on hardware, tested.
ffmpeg -hwaccel qsv -c:v h264_qsv -i "$1" -c:v hevc_qsv -global_quality:v $2 -preset:v 1 -profile:v 1 -c:a libopus -b:a 96K "$1-hevc-qsv-$2.mkv"

Encode to VP9 (in software):

#!/bin/env bash
# usage: enc.sh <source_file> <quality, e.g. 30, 0..63>
# https://trac.ffmpeg.org/wiki/Encode/VP9
ffmpeg -i "$1" -c:a libopus -b:a 96K -c:v libvpx-vp9 -b:v 0 -crf $2 -pass 1 -an -f null /dev/null
ffmpeg -i "$1" -c:a libopus -b:a 96K -c:v libvpx-vp9 -b:v 0 -crf $2 -pass 2 "`basename $1`_vp9tp_$2.webm"

Kensington Expert Mouse Linux config

#!/bin/bash
# 

LEFT_HANDED=""

show_help() {
  echo "Usage: [--left]"
  echo "--left = use lefthanded config"
  exit 1
}

parse_args() {
while [[ $# -gt 0 ]]; do
  case $1 in
    --left)
      LEFT_HANDED="yes"
      shift
      ;;
    *)
      show_help
      ;;
  esac
done
}

parse_args $@

MOUSE_NAME="Kensington Expert Mouse"
CHECK=$(xinput | grep "$MOUSE_NAME")

set -e

echo "check=$CHECK"

if [[ -z "$CHECK" ]]; then
    echo "Cannot find the device: $MOUSE_NAME"
    exit 1
fi

TRACKBALL_ID=$(xinput | grep "$MOUSE_NAME" | sed 's/^.*id=\([0-9]*\)[ \t].*$/\1/')

LEFT_TOP=2
LEFT_BOTTOM=1
RIGHT_TOP=8
RIGHT_BOTTOM=3
SCROLL_CLOCKWISE=5
SCROLL_COUNTERCW=4

# LB, LT, RB, SCCW, SCW, 6, 7, RT

MOUSE_LEFT=1
MOUSE_MIDDLE=2
MOUSE_RIGHT=3

# ---

# make scrolling with the ball smooth
SCROLLING_PIXEL_DISTANCE=50

# X clients receive events with logical button numbers, where 1, 2, 3 are usually interpreted as left, middle, right and logical buttons 4, 5, 6, 7 are usually interpreted as scroll up, down, left, right. The fourth and fifth physical buttons on a device will thus send logical buttons 8 and 9. The ButtonMapping option adjusts the logical button mapping, it does not affect how a physical button is mapped to a logical button.

if [[ -n $LEFT_HANDED ]]; then
    echo "using lefthanded config"
    SCROLLING_BUTTON=$RIGHT_TOP
    # LB, LT, RB, SCCW, SCW, 6, 7, RT
    BUTTON_MAP="$MOUSE_MIDDLE $MOUSE_RIGHT $MOUSE_LEFT 4 5 6 7 8"
else
    # right hand settings
    SCROLLING_BUTTON=$LEFT_TOP
    # LB, LT, RB, SCCW, SCW, 6, 7, RT
    BUTTON_MAP="$MOUSE_LEFT 8 $MOUSE_MIDDLE 4 5 6 7 $MOUSE_RIGHT"
fi

# -------
xinput set-prop $TRACKBALL_ID "libinput Scrolling Pixel Distance" $SCROLLING_PIXEL_DISTANCE
xinput set-prop $TRACKBALL_ID "libinput Button Scrolling Button" $SCROLLING_BUTTON
xinput set-prop $TRACKBALL_ID "libinput Scroll Method Enabled" 0, 0, 1
xinput set-button-map $TRACKBALL_ID 1 2 3 4 5 6 7 8 9
echo $BUTTON_MAP
xinput set-button-map $TRACKBALL_ID $BUTTON_MAP

BIOS update from Linux for Lenovo Thinkbook 13s g2 itl

You need to download intel ME driver, BIOS and ME firmware update installers: https://pcsupport.lenovo.com/lt/en/products/laptops-and-netbooks/thinkbook-series/thinkbook-13s-g2-itl 

Download windows 10 iso: https://www.microsoft.com/en-us/software-download/windows10ISO

Then you need wine to run those installers in Wine, select "Extract only". Then the installers and firmware apps need to be overlaid on the winpe.iso, which is made from the win10 iso as described there:

https://wiki.archlinux.org/title/Windows_PE

Then you mount winpe.iso and copy all the files to the FAT32 root partition on the USB flash. Copy EFI folder from the original Win10 iso.

After booting to USB flash drive (ENTER, F12) you go to firmware update directory and run respective ...Flash/install.bat

Then you need to enter BIOS Setup (ENTER, F1), and "Load Optimized Defaults".

After that you can update ME firmware the same way, booting from the USB, "...Flash/MEUpdate.bat"

High dpi displays better solution for laptops for Linux

 Instead of modifying each font size, it turned that adjusting only font scaling is enough.

In KDE it's "Fonts - System settings" -> "Force font DPI: 144" for 13 inch fullhd screen. Although in this way some apps may scale icons as well, e.g. LibreOffice. But still it's better than display scaling setting, which brakes some apps like Steam and games.

Raku programming language

Source "star" bundle takes forever to compile and ends with errors. Better to install only rakudo + zef bundle from here:

 https://rakudo.org/downloads

Slower than Python, REPL consumes 130MB ram.