biolds/tibuta-w100

Tibuta Linux W100 setup notes

Tibuta W100 Linux Setup Notes

This project contains notes about setting up Debian Bookworm on the Tibuta MasterPad W100 tablet (https://www.amazon.com/Tibuta-Masterpad-Computer-1536%C3%972048-Keyboard/dp/B09LS6Y2KT). It is highly recomended to backup the Windows partition, or make a dual boot when installing Linux.

It aims to cover system setup and IceWM lightweight window manager setup. Not yet working:

• Volume buttons
• Display power management bug (sometime after going into power saving mode, the screen won't light back)
• Screen sometime blinking in console mode
• Accelerometers (automatically switch between landscape and portrait modes)
• Suspend on lid close

Feel free to post a pull request to improve this doc or open a discussion. Please put a star if it was useful to you.

Wifi

By default it is not possible to power on the Wifi SoC, there seems to be some problem with the default power management config. Setting pcie_port_pm=off kernel parameter solves it.

1. Open /etc/default/grub in a text editor (with root access rights), and add pcie_port_pm=off to the end of GRUB_CMDLINE_LINUX_DEFAULT variable.
2. Run sudo grub-update to save the new settings.
3. Reboot.

Touchscreen

Using the touchscreen requires rebuilding the kernel to enable custom settings, and update the silead module.

A patched kernel based on the latest Debian kernel can be downloaded from https://gitlab.com/biolds1/tibuta-w100-kernel/-/pipelines?scope=tags&page=1 (click on the Download button, then kernel:archive).

The firmware needs to be copied manually into /lib/firmware/silead/.

export PATH=/sbin:/usr/sbin:$PATH
mkdir /lib/firmware/silead/
cp gsl1680-tibuta-w100.fw /lib/firmware/silead/
dpkg -i linux-image-6.1.76-tibuta_6.1.76-tibuta-1_amd64.deb

Kernel building

Alternatively the kernel can be built manually, as described on gls-firmware Github page.

A patch is required to load the new firmware, updated debian kernel conf and cert, etc.

Another patch is needed to correct the orientation of the camera sensors.

apt-get install build-essential linux-source-6.1 bc kmod cpio flex libncurses5-dev libelf-dev libssl-dev dwarves bison python3
cd /root
tar xaf /usr/src/linux-source-6.1.tar.xz
cd linux-source-6.1
patch -p 1 < 0001-tibuta-touchpad-module.patch
patch -p 1 < 0002-uvc-quirks-to-flip-image.patch
make -j2 deb-pkg

Setup/integration

Using the kernel above the touchscreen does not match the screen matrix, this can adapted using the following scripts (which also handle screen rotation, and resizing), and installing the xinput package:

/usr/local/bin/screen-landscape

#!/usr/bin/bash
xrandr --output eDP-1 --scale 1x1
xrandr -o left
xinput set-prop pointer:silead_ts 'Coordinate Transformation Matrix' 0 -1.17 1.17 1.32 0 -0.32 0 0 1
xrandr --output eDP-1 --scale 0.5x0.5

/usr/local/bin/screen-portrait

#!/usr/bin/bash
xrandr --output eDP-1 --scale 1x1
xrandr -o normal
xinput set-prop pointer:silead_ts 'Coordinate Transformation Matrix' 1.32 0 -0.32 0 1.17 -0.17 0 0 1
xrandr --output eDP-1 --scale 0.5x0.5

/usr/local/bin/screen-switch

#!/usr/bin/bash
if xrandr | grep '^eDP-1 connected primary 1024x768+0+0 left'
then
    /usr/local/bin/screen-portrait
else
    /usr/local/bin/screen-landscape
fi

Note: the matrix coordinates are usable as is but could be improved, please make a PR if you fine-tune them.

HDMI output

The following script will setup HDMI output while keeping the tablet screen in landscape scaled mode, but this breaks the touchscreen scaling done above (I did not bother building the correct xinput commands, since a mouse is required anyway to access the external screen):

/usr/local/bin/screen-hdmi

#!/bin/bash
xrandr --output HDMI-1 --off # Reset the output in case it's in a bad state
xrandr --output eDP-1 --scale 1x1 --auto
xrandr --output HDMI-1 --auto --mode 1920x1080
xrandr --output HDMI-1 --auto --right-of eDP-1
xrandr --output eDP-1 --mode 1536x2048 -o left --scale 0.5x0.5

/usr/local/bin/screen-hdmi-off

#!/bin/bash
xrandr --output HDMI-1 --off

Touchscreen gestures

Touchegg can be installed to handle right-click/scroll with 2 fingers. (seems like it's also required for the touchpad)

On IceWM, touchegg-client needs to be run at startup, in .icewm/startup with /usr/bin/touchegg --client &.

Login screen

LightDM setup for tablet that don't handle screen rotation:

• screen scaling, and landscape mode: lightdm.conf
• conf to have Onboard in the accessibility menu: lightdm-gtk-greeter.conf (to be put in /etc/lightdm)

Backlight

The backlight can be changed through /sys/class/backlight/intel_backlight:

/usr/local/bin/backlight-dec

#!/bin/bash
set -e

PERCENT=10
SYSFS_BL=/sys/class/backlight/intel_backlight
MAX="$(cat $SYSFS_BL/max_brightness)"
CURRENT="$(cat $SYSFS_BL/brightness)"

STEP="$(($MAX * $PERCENT / 100))"
NEW="$(($CURRENT - $STEP))"

if [ "$NEW" -lt 0 ]
then
	NEW=0
fi

echo "$NEW" > $SYSFS_BL/brightness

/usr/local/bin/backlight-inc

#!/bin/bash
set -e

PERCENT=10
SYSFS_BL=/sys/class/backlight/intel_backlight
MAX="$(cat $SYSFS_BL/max_brightness)"
CURRENT="$(cat $SYSFS_BL/brightness)"

STEP="$(($MAX * $PERCENT / 100))"
NEW="$(($CURRENT + $STEP))"

if [ "$NEW" -gt "$MAX" ]
then
	NEW="$MAX"
fi

echo "$NEW" > $SYSFS_BL/brightness

Create a udev rule to make the backlight device modifiable by regular users:

/etc/udev/rules.d/backlight.rules

ACTION=="add", SUBSYSTEM=="backlight", RUN+="/bin/chgrp video $sys$devpath/brightness", RUN+="/bin/chmod g+w $sys$devpath/brightness"

And make sure regular users are part of the video group.

Suspend on power button

Set HandlePowerKey=suspend in /etc/systemd/login.conf

Soundcard

The ES8336 chipset for sound requires at least a 6.0 kernel and installing the firmwares provided by the SOF project, by following the Readme.

When it's installed, run alsamixer, hit F6 and select "sof-essx8336". Unmute all chanels and increase their volume, only one chanel DAC Mono needs to be kept muted to enable stereo sound.

Shortcut keys

Shortcut keys can be setup with xbindkeys:

~/.xbindkeysrc

# Increase backlight
"/usr/local/bin/backlight-inc"
   XF86MonBrightnessUp

# Decrease backlight
"/usr/local/bin/backlight-dec"
   XF86MonBrightnessDown

# Increase volume
"pactl set-sink-volume @DEFAULT_SINK@ +1000"
   XF86AudioRaiseVolume

# Decrease volume
"pactl set-sink-volume @DEFAULT_SINK@ -1000"
   XF86AudioLowerVolume

xbindkeys then needs to be started from ~/.icewm/startup.

Bluetooth

Works out of the box, see https://wiki.debian.org/BluetoothUser.

Debian packages

apt install lightdm icewm xinput xbindkeys chromium pcmanfm onboard tilix pavucontrol firmware-linux-nonfree bluetooth rfkill blueman papirus-icon-theme adwaita-icon-theme

IceWM

A theme with big buttons that can be used on a touchscreen is available there: https://www.antixforum.com/forums/topic/new-theme-for-antix-icewm/

~/.icewm/toolbar:

# This is a default toolbar definition file for IceWM
#
# Place your personal variant in $HOME/.icewm directory.

prog Tilix terminal.png tilix
prog PCManFM /usr/share/icons/Papirus/64x64/apps/fma-config-tool.svg pcmanfm
#prog FTE fte fte
#prog Netscape netscape netscape
#prog    "Vim" vim /usr/bin/gvim -f
prog    "WWW" ! x-www-browser
prog Switch /usr/share/icons/Adwaita/64x64/actions/view-refresh-symbolic.symbolic.png /usr/local/bin/screen-switch

~/.icewm/startup

#!/bin/bash
/usr/bin/onboard &
/usr/bin/touchegg --client &
/usr/bin/blueman-applet
/usr/bin/xbindkeys

Tablet panel

To control the backlight and volume while the keyboard is detached, I have written a small UI tool available there: https://gitlab.com/biolds1/tabletpanel

You can make it launchable when taping on the clock in the taskbar by adding this line in ~/.icewm/preferences:

ClockCommand="/usr/bin/python3 /usr/local/bin/tabletpanel"

Mainline Kernel >= 5.19

Many distributions ship with a kernel that have PCI E820 reservations disabled by default for models that were manufactured in, or after 2023.

When such a kernel is installed, the system fails to boot, and emits the following message quite a few times:

[$TIMESTAMP] mmc0: Reset 0x1 never completed.
[$TIMESTAMP] mmc0: sdhci: ========== SDHCI REGISTER DUMP ==========
[$TIMESTAMP] mmc0: sdhci: Sys addr:  0xffffffff | Version:  0x0000ffff
[$TIMESTAMP] mmc0: sdhci: Blk size:  0x0000ffff | Blk cnt:  0x0000ffff
[$TIMESTAMP] mmc0: sdhci: Argument:  0xffffffff | Trn mode: 0x0000ffff
[$TIMESTAMP] mmc0: sdhci: Present:   0xffffffff | Host ctl: 0x000000ff
[$TIMESTAMP] mmc0: sdhci: Power:     0x000000ff | Blk gap:  0x000000ff
[$TIMESTAMP] mmc0: sdhci: Wake-up:   0x000000ff | Clock:    0x0000ffff
[$TIMESTAMP] mmc0: sdhci: Timeout:   0x000000ff | Int stat: 0xffffffff
[$TIMESTAMP] mmc0: sdhci: Int enab:  0xffffffff | Sig enab: 0xffffffff
[$TIMESTAMP] mmc0: sdhci: ACmd stat: 0x0000ffff | Slot int: 0x0000ffff
[$TIMESTAMP] mmc0: sdhci: Caps:      0xffffffff | Caps_i:   0xffffffff
[$TIMESTAMP] mmc0: sdhci: Cmd:       0x0000ffff | Max curr: 0xffffffff
[$TIMESTAMP] mmc0: sdhci: Resp[0]:   0xffffffff | Resp[1]:  0xffffffff
[$TIMESTAMP] mmc0: sdhci: Resp[2]:   0xffffffff | Resp[3]:  0xffffffff
[$TIMESTAMP] mmc0: sdhci: Host ctl2: 0x0000ffff
[$TIMESTAMP] mmc0: sdhci: ADMA Err:  0xffffffff | ADMA Ptr: 0xffffffffffffffff
[$TIMESTAMP] mmc0: sdhci: ==========================================

When this happens, using pci=use_e820 kernel parameter lets the system boot.

In case there is no working kernel installed in the system, the argument can be applied in an ad-hoc way, in grub:

1. On the grub screen press e to edit the boot command while having the default option selected.
2. Find the line that starts with linux
3. Add pci=use_e820 to the end of the line.
4. Press Ctrl-X to boot.

To apply the parameter permanently, edit the grub settings:

1. Open /etc/default/grub in a text editor (with root access rights), and add pci=use_e820 to the end of GRUB_CMDLINE_LINUX_DEFAULT variable.
2. Run sudo grub-update to save the new settings.
3. Reboot.

Camera

The camera sensors seem to be mounted with a random orientation. The included kernel patch introduces 2 quirks, one to horizontally flip the image, and one to vertically flip it. The known camera IDs are included in the patch, and the orientation should be corrected automatically.

To control the flipping manually, the module can be loaded with setting the quirks manually.

Module param	Effect
quirks=0x40000000	Force vertical flipping
quirks=0x80000000	Force horizontal flipping
quirks=0xc0000000	Force vertical and horizontal flipping
quirks=0x0	Force disable flipping

Note that the rear camera's image is not flipped in all cases.

If you have a tablet with a camera that's not handled by the driver automaticaly, feel free to open an issue (or PR) to add it.