Fix little-rascal touchpad support and update AMD GPU config

- Add ITE8353 touchpad support with I2C HID modules
- Configure libinput for proper touchpad functionality
- Add udev rules for touchpad device permissions
- Simplify AMD GPU config to use open source drivers only
- Remove ROCm and 32-bit support for cleaner configuration
- Add diagnostic script for touchpad troubleshooting

scripts/diagnose-trackpad.sh

@@ -0,0 +1,85 @@
+#!/usr/bin/env bash
+# Trackpad Diagnostic Script for Little-Rascal
+# This script helps diagnose trackpad issues on NixOS
+
+echo "=== Little-Rascal Trackpad Diagnostics ==="
+echo "Date: $(date)"
+echo
+
+echo "1. Checking for input devices..."
+if command -v libinput >/dev/null 2>&1; then
+    echo "   ✓ libinput is available"
+    echo "   Input devices detected by libinput:"
+    sudo libinput list-devices | grep -E "(Device:|Capabilities:)" | head -20
+else
+    echo "   ✗ libinput not found - this could be the problem!"
+fi
+echo
+
+echo "2. Checking systemd services..."
+if systemctl is-active --quiet systemd-logind; then
+    echo "   ✓ systemd-logind is running"
+else
+    echo "   ✗ systemd-logind is not running"
+fi
+echo
+
+echo "3. Checking for trackpad hardware..."
+if ls /dev/input/mouse* >/dev/null 2>&1; then
+    echo "   ✓ Mouse devices found:"
+    ls -la /dev/input/mouse*
+else
+    echo "   ⚠ No mouse devices found in /dev/input/"
+fi
+
+if ls /dev/input/event* >/dev/null 2>&1; then
+    echo "   ✓ Event devices found:"
+    ls -la /dev/input/event* | wc -l
+    echo "     Total event devices: $(ls /dev/input/event* | wc -l)"
+else
+    echo "   ✗ No event devices found"
+fi
+echo
+
+echo "4. Checking kernel modules..."
+modules=("i2c_hid" "hid_multitouch" "psmouse")
+for module in "${modules[@]}"; do
+    if lsmod | grep -q "$module"; then
+        echo "   ✓ $module module is loaded"
+    else
+        echo "   ⚠ $module module not loaded (may not be needed)"
+    fi
+done
+echo
+
+echo "5. Checking for specific laptop touchpad info..."
+if command -v dmesg >/dev/null 2>&1; then
+    echo "   Recent touchpad-related kernel messages:"
+    dmesg | grep -i -E "(touchpad|synaptics|elan|input)" | tail -5
+fi
+echo
+
+echo "6. User permissions..."
+echo "   Current user: $(whoami)"
+echo "   User groups: $(groups)"
+if groups | grep -q input; then
+    echo "   ✓ User is in 'input' group"
+else
+    echo "   ⚠ User not in 'input' group (usually not required on NixOS)"
+fi
+echo
+
+echo "=== Recommendations ==="
+echo "If trackpad still doesn't work after enabling libinput:"
+echo "1. Reboot the system to ensure all changes take effect"
+echo "2. Try: sudo libinput debug-events (to see if events are being detected)"
+echo "3. Check dmesg for hardware detection issues"
+echo "4. Consider adding specific kernel modules if hardware isn't detected"
+echo
+
+echo "=== Configuration Status ==="
+if grep -q "services.libinput.enable.*true" /etc/nixos/configuration.nix 2>/dev/null; then
+    echo "   ✓ libinput appears to be enabled in configuration"
+else
+    echo "   ⚠ libinput may not be enabled - check your NixOS configuration"
+fi