Dell XPS 13开发者版Ubuntu 16.04触摸板失灵求助

Hey Carl, let's work through this touchpad issue step by step—great call ruling out hardware with the live USB first! Here are targeted fixes tailored to your Dell XPS setup:

1. Quick Reset of Touchpad Kernel Modules #

Temporary glitches after display changes often clear up with a module reload:

sudo modprobe -r i2c_hid && sudo modprobe i2c_hid

If that doesn’t help, restart the display server to refresh input settings:

sudo systemctl restart lightdm

2. Resolve Xorg Configuration Conflicts #

External monitor setups can generate conflicting touchpad configs. Let’s clean this up:

• Check for existing touchpad config files:

  ls /etc/X11/xorg.conf.d/
  

• If you see files like 70-synaptics.conf or 90-touchpad.conf, back them up and delete them (e.g., sudo mv /etc/X11/xorg.conf.d/70-synaptics.conf ~/touchpad-backup/), then restart your system.
• If no config exists, create a minimal libinput config to enforce touchpad recognition:

  sudo nano /etc/X11/xorg.conf.d/90-libinput.conf
  

  Paste this content:

  Section "InputClass"
      Identifier "Dell XPS Touchpad"
      MatchIsTouchpad "on"
      Driver "libinput"
      Option "Tapping" "on" # Optional: Enable tap-to-click
      Option "NaturalScrolling" "on" # Optional: Enable natural scrolling
  EndSection
  

  Save with Ctrl+O, exit with Ctrl+X, then restart the display server.

3. Tweak Kernel Boot Parameters (Dell XPS-Specific) #

You mentioned trying GRUB configs before—let’s use parameters known to fix Dell touchpad issues:

• Open the GRUB config file:

  sudo nano /etc/default/grub
  

• Modify the GRUB_CMDLINE_LINUX_DEFAULT line to add this parameter:

  GRUB_CMDLINE_LINUX_DEFAULT="quiet splash i2c_hid.polling_mode=1"
  

• Update GRUB and reboot:

  sudo update-grub
  sudo reboot
  

4. Disable Aggressive Touchpad Power Saving #

Ubuntu sometimes enables power saving for the touchpad after display changes. Let’s turn this off:

• Install powertop to inspect power settings:

  sudo apt update && sudo apt install powertop
  

• Run powertop and navigate to the Tunables tab. Look for entries related to your touchpad (e.g., Runtime PM for I2C Adapter i2c-DELL07E6:00). If it shows "Good", toggle it to "Bad" to disable power saving.
• Make this change permanent:

  sudo powertop --auto-tune
  

5. Refresh Touchpad Drivers #

Corrupted driver files could be the root cause. Let’s reinstall them:

sudo apt purge xserver-xorg-input-synaptics xserver-xorg-input-libinput
sudo apt install xserver-xorg-input-libinput
sudo reboot

If none of these steps work, grab debug logs to dig deeper:

dmesg | grep -i touchpad
journalctl -xe | grep -i touchpad

Share those logs and we can troubleshoot further!

内容的提问来源于stack exchange，提问作者Carl