controller-led

#!/usr/bin/env bash
# controller-led — DualSense LED helper for the controller-manager daemon.
#
#   controller-led lightbar-raw <hidrawN> <r> <g> <b>  # lightbar via raw HID
#   controller-led <ledname> <r> <g> <b>               # lightbar via LED class
#   controller-led player <inputN> <1-4>               # white player-LED pattern
#
# The lightbar is driven with a RAW HID output report (lightbar-raw). Unlike a
# kernel LED-class write, a raw colour report also clears the DualSense firmware
# "light out" latch, so the colour reaches the hardware even after a raw-HID
# consumer (Steam Input) has latched the pad dark — the LED-class write updates
# the sysfs node but leaves such a latched lightbar physically off. The old
# LED-class path (<ledname>) is kept for reference/compat. The white player LEDs
# go through the LED class, which drives them reliably.
#
# Safety: only a *:rgb:indicator / *:white:player-N LED or a /dev/hidrawN node
# that belongs to a Sony (054C) HID device is ever written, so this can't be
# aimed at unrelated LEDs/devices (keyboard, NIC, …). Meant to be invoked
# through a tightly-scoped NOPASSWD sudoers rule.

set -euo pipefail

# HID_ID=BUS:0000VVVV:0000PPPP -> extract the 4-digit vendor; must be Sony.
sony_ok() {
  local ue="$1"
  [[ -r "$ue" ]] || { echo "cannot read $ue" >&2; return 1; }
  local vid
  vid="$(sed -n 's/^HID_ID=[0-9A-Fa-f]*:0*\([0-9A-Fa-f]\{4\}\):.*/\1/p' "$ue" | tr 'a-f' 'A-F')"
  [[ "$vid" == "054C" ]] || { echo "vendor '$vid' not Sony — refused" >&2; return 1; }
}

if [[ "${1:-}" == "player" ]]; then
  prefix="${2:-}"; n="${3:-}"
  [[ "$prefix" =~ ^input[0-9]+$ ]] || { echo "bad prefix '$prefix'" >&2; exit 2; }
  [[ "$n" =~ ^[1-4]$ ]] || { echo "bad player '$n'" >&2; exit 2; }
  base="/sys/class/leds/$prefix:white:player-1"
  [[ -d "$base" ]] || { echo "$base absent, nothing to do"; exit 0; }
  sony_ok "$base/device/uevent" || exit 3
  # PS5-authentic patterns: the lit-LED count equals the player number.
  case "$n" in
    1) pat=(0 0 1 0 0) ;;
    2) pat=(0 1 0 1 0) ;;
    3) pat=(1 0 1 0 1) ;;
    4) pat=(1 1 0 1 1) ;;
  esac
  for i in 1 2 3 4 5; do
    dir="/sys/class/leds/$prefix:white:player-$i"
    [[ -d "$dir" ]] && echo "${pat[$((i - 1))]}" > "$dir/brightness"
  done
  echo "controller-led: $prefix player -> $n"
  exit 0
fi

if [[ "${1:-}" == "lightbar-raw" ]]; then
  node="${2:-}"; r="${3:-}"; g="${4:-}"; b="${5:-}"
  # A plain /dev/hidrawN node (no path traversal, no other class).
  [[ "$node" =~ ^/dev/hidraw[0-9]+$ ]] || { echo "bad hidraw '$node'" >&2; exit 2; }
  # Node already gone (controller disconnected mid-write) — nothing to do.
  [[ -e "$node" ]] || { echo "$node absent, nothing to do"; exit 0; }
  for v in "$r" "$g" "$b"; do
    { [[ "$v" =~ ^[0-9]+$ ]] && (( v <= 255 )); } || { echo "bad channel '$v'" >&2; exit 2; }
  done
  ue="/sys/class/hidraw/$(basename "$node")/device/uevent"
  sony_ok "$ue" || exit 3
  # Bus from HID_ID=BUS:0000VVVV:0000PPPP — 0005 Bluetooth (report 0x31 + CRC),
  # 0003 USB (report 0x02, no CRC): the two wire formats differ.
  bus="$(sed -n 's/^HID_ID=\([0-9A-Fa-f]*\):.*/\1/p' "$ue")"
  if python3 - "$node" "$bus" "$r" "$g" "$b" <<'PY'
import sys, zlib
node = sys.argv[1]
bt = int(sys.argv[2], 16) == 5              # BUS_BLUETOOTH
r, g, b = (int(x) & 0xff for x in sys.argv[3:6])
# DualSense output_report_common. valid_flag1 bit2 = LIGHTBAR_CONTROL sets the
# colour; valid_flag2 bit1 = LIGHTBAR_SETUP_CONTROL_ENABLE with lightbar_setup=0
# ("normal", not LIGHT_OUT=2) re-enables the bar. Both are needed: some DualSense
# firmwares light up on LIGHTBAR_CONTROL alone, others ignore a plain colour
# while latched and only obey it together with the setup flag (field-observed
# across two pads, 2026-07-13). Sending both clears the "light out" latch and
# sets the colour on either firmware.
common = bytearray(47)
common[1]  = 0x04                           # valid_flag1: LIGHTBAR_CONTROL
common[38] = 0x02                           # valid_flag2: LIGHTBAR_SETUP_CONTROL_ENABLE
common[41] = 0x00                           # lightbar_setup: 0 = normal/on
common[44], common[45], common[46] = r, g, b
if bt:                                       # BT: 0x31, seq_tag, tag, CRC32 tail
    rep = bytearray(78)
    rep[0], rep[1], rep[2] = 0x31, 0x00, 0x10
    rep[3:3 + 47] = common
    crc = zlib.crc32(bytes([0xA2]) + bytes(rep[0:74])) & 0xffffffff  # seed 0xA2
    rep[74:78] = crc.to_bytes(4, "little")
else:                                        # USB: 0x02, no CRC
    rep = bytearray(48)
    rep[0] = 0x02
    rep[1:1 + 47] = common
with open(node, "wb") as f:
    f.write(bytes(rep))
PY
  then
    echo "controller-led: lightbar-raw $node -> $r $g $b (bus $bus)"
    exit 0
  fi
  echo "lightbar-raw: write to $node failed" >&2
  exit 1
fi

led="${1:-}"; r="${2:-}"; g="${3:-}"; b="${4:-}"

# Name only (never a path) — refuse anything but a plain rgb-indicator led name.
[[ "$led" =~ ^[A-Za-z0-9_.:-]+:rgb:indicator$ ]] || { echo "bad led '$led'" >&2; exit 2; }

dir="/sys/class/leds/$led"
# Node already gone (e.g. controller disconnected mid-write) — nothing to do.
[[ -d "$dir" ]] || { echo "$dir absent, nothing to do"; exit 0; }

# Channels must be integers 0-255.
for v in "$r" "$g" "$b"; do
  { [[ "$v" =~ ^[0-9]+$ ]] && (( v <= 255 )); } || { echo "bad channel '$v'" >&2; exit 2; }
done

sony_ok "$dir/device/uevent" || exit 3

printf '%s' "$r $g $b" > "$dir/multi_intensity"
echo 255 > "$dir/brightness"
echo "controller-led: $led -> $r $g $b"
exit 0