feat: HDMI-CEC with Valve's cecd, on any PC

Opt-in menu item: cecd, cec-audio-control and inputattach-cec-units from
Valve's holo repository (SHA-256 checked). Works with any /dev/cec*.

CHANGELOG.md

@@ -5,6 +5,17 @@ All notable changes, per version and per commit. Versions follow
 `steamify.sh`. Versions before 0.7.0 were numbered afterwards,
 one per merged pull request.
 
+## 1.1.0 - 2026-09-25
+
+- **feat: HDMI-CEC** (experimental, never ticked by default, on every PC)
+  - Valve's `cecd`, `cec-audio-control` and `inputattach-cec-units` from its
+    SteamOS repository (SHA-256 checked): use Steam with the TV remote, and
+    the TV turns on and off with the PC. On a Steam Machine, steamos-manager
+    configures it from Steam's settings.
+  - Works with any `/dev/cec*` (GPU or USB adapter); the menu lists them.
+  - The README no longer says Steam Machine support alone gives HDMI-CEC:
+    `cecd` wasn't installed, so it didn't.
+
 ## 1.0.0 - 2026-09-25
 
 - **feat: Pin the kernel to 7.1.6-1 on a Steam Machine**

README.md

@@ -27,13 +27,17 @@ Steam Machine.
    ([details](TECHNICAL.md#single-user-mode-sddm-no-locking)).
 5. **Steamify shortcut** - an icon on the desktop and in the launcher that
    opens the newest Steamify, so you don't need the install command again.
+6. **HDMI-CEC** (experimental, off by default) - use Steam with your TV's
+   remote, and the TV turns on and off with the PC. Needs a GPU with CEC (like
+   the Steam Machine) or a USB CEC adapter
+   ([details](TECHNICAL.md#hdmi-cec)).
 
 ## Steam Machine
 
 On a Valve Steam Machine the menu has two more items:
 
 - **Steam Machine support** - the front **LED bar** works, Steam's
-  **hardware settings** (fan, TV control over HDMI-CEC) work, and the power
+  **hardware settings** (fan, performance) work, and the power
   button puts it to sleep like a console.
   - **Pin the kernel to 7.1.6-1** - on by default: with newer CachyOS kernels
     the Steam Machine reboots instead of shutting down. Untick it once CachyOS

TECHNICAL.md

@@ -154,8 +154,9 @@ The **Steam Machine support** component, only shown on Fremont hardware
 - console-like power button: it puts the machine to sleep, and it never
   suspends by itself on mains power (the launcher's Shut Down still shuts down);
 - installs and enables `steamos-manager`, the service Steam in gaming mode
-  uses for hardware settings (fan, HDMI-CEC, performance); it recognises the
-  Steam Machine from its DMI data.
+  uses for hardware settings (fan, performance, and the HDMI-CEC settings
+  when [HDMI-CEC](#hdmi-cec) is on); it recognises the Steam Machine from its
+  DMI data.
 
 Turning it off removes all of that again (the AUR helper is kept).
 
@@ -168,6 +169,35 @@ or upgraded. A newly added kernel doesn't come with its headers, so
 `ensure-kernel-headers.service` checks at every boot and installs any
 missing `-headers` package, which makes DKMS build the driver for it.
 
+## HDMI-CEC
+
+The **HDMI-CEC** item (on every PC, never ticked by default) installs
+Valve's CEC stack from its SteamOS `holo` repository, the newest `holo-X.Y`
+on `steamdeck-packages.steamos.cloud`, each package checked against the
+SHA-256 in Valve's package index:
+
+- `cecd`, Valve's CEC daemon (a user service started with the desktop and
+  gaming mode): TV remote keys become normal key presses (arrows, Enter,
+  Back), and it turns the TV on and off with the PC;
+- `cec-audio-control`: volume of the TV or receiver;
+- `inputattach-cec-units` (with `linuxconsole` from CachyOS for
+  `inputattach`): attaches USB CEC adapters (Pulse-Eight, RainShadow).
+
+It works with any `/dev/cec*`: a GPU that has CEC on its HDMI port (the
+Steam Machine; the CachyOS kernel has DisplayPort CEC built in) or a USB
+adapter. The menu lists the CEC devices found. Also turn on CEC on the TV
+(Sony: BRAVIA Sync, Samsung: Anynet+, LG: SimpLink). On a Steam Machine
+`steamos-manager` writes cecd's settings from Steam's (wake the TV, put it to
+sleep), in `~/.config/cecd/config.d/`.
+
+It's experimental: on SteamOS itself CEC can wake the Steam Machine right
+after it goes to sleep (Samsung TVs,
+[SteamOS#2626](https://github.com/ValveSoftware/SteamOS/issues/2626)) and
+upset CEC for the TV's other devices
+([SteamOS#2817](https://github.com/ValveSoftware/SteamOS/issues/2817)).
+Turning it off removes the packages again (`linuxconsole` only if the
+wizard installed it).
+
 ## Kernel pin (Steam Machine)
 
 With CachyOS kernels newer than 7.1.6 a Steam Machine reboots instead of
@@ -256,6 +286,7 @@ immediately, which can turn into a loop - see
 | `lib/single-user.sh` | Single user mode: no lock screen, user switching or log out |
 | `lib/wizard-shortcut.sh` | Steamify shortcut: desktop icon and launcher entry that run the newest release |
 | `lib/bios.sh` | Update BIOS (Steam Machine, opt-in): current/newest version, double confirmation, fwupd |
+| `lib/cec.sh` | HDMI-CEC: Valve's `cecd` and friends from its `holo` repository |
 | `lib/steam-machine.sh` | Steam Machine support: LED driver, LED access, steamos-manager; kernel pin |
 | `.github/tools/bundle.sh` | Builds the single-file version (`dist/steamify.sh`) |
 | `.github/workflows/bundle.yml` | Builds and checks it on every push; publishes it on `main` |

TROUBLESHOOTING.md

@@ -32,6 +32,24 @@ cat /var/lib/dkms/leds-valve-dkms/0.1/build/make.log
 journalctl --user -b | grep -i led
 ```
 
+## The TV remote does nothing (HDMI-CEC)
+
+- Turn on CEC in the TV's settings (Sony: BRAVIA Sync, Samsung: Anynet+, LG:
+  SimpLink) and, if it has one, allow the PC to control it.
+- Check that the PC has a CEC device, and that `cecd` runs:
+
+```bash
+ls /dev/cec*
+systemctl --user status cecd
+journalctl --user -u cecd -b
+cec-ctl -d /dev/cec0 -S        # the devices on the TV's CEC bus (v4l-utils)
+```
+
+No `/dev/cec*`: your GPU's HDMI port has no CEC; a USB CEC adapter
+(e.g. Pulse-Eight) works. The Steam Machine wakes up again right after going
+to sleep, or other devices lose CEC? That happens on SteamOS too; turn
+HDMI-CEC off in the wizard.
+
 ## The Steam Machine still reboots when I shut it down
 
 Check that the pinned kernel is installed and running:

lib/cec.sh

@@ -0,0 +1,88 @@
+#!/bin/bash
+# "HDMI-CEC" menu item, on any PC: Valve's CEC daemon (cecd), TV/receiver
+# volume control (cec-audio-control) and the units that attach USB CEC
+# adapters (Pulse-Eight, RainShadow) with inputattach. They're only in
+# Valve's SteamOS (holo) repository, not in CachyOS or the AUR. Works with
+# any /dev/cec*: a GPU with CEC (e.g. the Steam Machine) or a USB adapter.
+# On a Steam Machine, steamos-manager configures cecd from Steam's settings.
+# Sourced by steamify.sh; not meant to be run on its own.
+
+CEC_PKGS=(cecd cec-audio-control inputattach-cec-units)
+
+cec_status() { pacman -Q "${CEC_PKGS[@]}" >/dev/null 2>&1; }
+
+fetch_holo_pkg() {
+    # fetch_holo_pkg <dir> <package>: download the newest <package> from
+    # Valve's newest holo repository into <dir> and print its path. The
+    # SHA-256 comes from Valve's package index and is verified.
+    local dir="$1" name="$2" repo desc file_name sha256
+    repo="$(curl -fsL "$VALVE_MIRROR/" | grep -oE 'holo-[0-9]+\.[0-9]+/' | tr -d / | sort -V | tail -n 1)"
+    if [[ ! -f "$dir/holo.db" ]]; then
+        [[ -n "$repo" ]] && curl -fsL "$VALVE_MIRROR/$repo/os/x86_64/$repo.db" -o "$dir/holo.db" ||
+            { err "Couldn't read Valve's SteamOS package index ($VALVE_MIRROR)."; return 1; }
+    fi
+    desc="$(tar -tf "$dir/holo.db" 2>/dev/null | grep -E "^$name-[0-9][^/]*/desc$" | head -n 1)"
+    [[ -n "$desc" ]] || { err "No $name in Valve's $repo repository."; return 1; }
+    file_name="$(tar -xOf "$dir/holo.db" "$desc" | awk '/^%FILENAME%$/ { getline; print }')"
+    sha256="$(tar -xOf "$dir/holo.db" "$desc" | awk '/^%SHA256SUM%$/ { getline; print }')"
+    info "Downloading $file_name ($repo)..." >&2
+    curl -fsL "$VALVE_MIRROR/$repo/os/x86_64/$file_name" -o "$dir/$file_name" ||
+        { err "Downloading $file_name failed."; return 1; }
+    echo "$sha256  $dir/$file_name" | sha256sum -c --quiet - >&2 ||
+        { err "Checksum mismatch for $file_name; not using it."; return 1; }
+    echo "$dir/$file_name"
+}
+
+cec_enable() {
+    local tmp p f files=()
+    # inputattach, needed by inputattach-cec-units.
+    if ! pacman -Q linuxconsole >/dev/null 2>&1; then
+        sudo pacman -S --needed --noconfirm linuxconsole || { err "Installing linuxconsole failed."; return 1; }
+        state_set cec installed_linuxconsole 1
+    fi
+    tmp="$(mktemp -d)"
+    for p in "${CEC_PKGS[@]}"; do
+        f="$(fetch_holo_pkg "$tmp" "$p")" || { rm -rf "$tmp"; return 1; }
+        files+=("$f")
+    done
+    info "Installing Valve's CEC daemon..."
+    if ! sudo pacman -U --needed --noconfirm "${files[@]}"; then
+        rm -rf "$tmp"
+        err "Installing ${CEC_PKGS[*]} failed."
+        return 1
+    fi
+    rm -rf "$tmp"
+    # Its udev rule gives the user /dev/cec*; cecd starts with the graphical
+    # session, after steamos-manager wrote its config from Steam's settings.
+    sudo udevadm control --reload
+    sudo udevadm trigger --subsystem-match=cec --action=add
+    systemctl --user daemon-reload
+    systemctl --user enable steamos-manager-configure-cecd.service 2>/dev/null
+    if compgen -G "/dev/cec*" >/dev/null; then
+        systemctl --user restart cecd.service 2>/dev/null
+        ok "HDMI-CEC on ($(cd /dev && echo cec*)). Turn on CEC on your TV too (e.g. Sony: BRAVIA Sync, Samsung: Anynet+, LG: SimpLink)."
+    else
+        warn "No CEC device (/dev/cec*) found: your GPU may not support CEC. A USB CEC adapter"
+        warn "(e.g. Pulse-Eight) works too. Check again after a restart with: ls /dev/cec*"
+    fi
+}
+
+cec_disable() {
+    info "Removing HDMI-CEC..."
+    systemctl --user disable --now cecd.service cec-audio-control.socket cec-audio-control.service 2>/dev/null
+    systemctl --user disable steamos-manager-configure-cecd.service 2>/dev/null
+    sudo pacman -Rns --noconfirm "${CEC_PKGS[@]}" 2>/dev/null
+    if [[ -n "$(state_get cec installed_linuxconsole)" ]]; then
+        sudo pacman -Rns --noconfirm linuxconsole 2>/dev/null
+        state_clear cec
+    fi
+    sudo udevadm control --reload
+    ok "HDMI-CEC removed."
+}
+
+cec_overview() {
+    # For the menu's kernel overview.
+    local dev="none"
+    compgen -G "/dev/cec*" >/dev/null && dev="$(cd /dev && echo cec*)"
+    echo "CEC devices: $dev  cecd: $(systemctl --user is-active cecd 2>/dev/null)"
+}

lib/menu.sh

@@ -5,15 +5,16 @@
 
 # Menu order. Components are turned on in this order and off in reverse;
 # gaming must come first (single user builds on it).
-COMPONENTS=(gaming boot theme glyphs single launcher machine kpin bios)
+COMPONENTS=(gaming boot theme glyphs single launcher cec machine kpin bios)
 # One-off actions rather than on/off components: never preselected, never
 # re-applied, not listed as on or off.
 ACTIONS=(bios)
 # Sub-options, shown indented under their parent and only while it's ticked.
 declare -A PARENT=([boot]=gaming [kpin]=machine)
 # Never preselected on a first run: booting into the desktop is a choice,
-# gamescope is the default.
-NO_PRESELECT=(boot)
+# gamescope is the default; HDMI-CEC is opt-in (it can wake the machine or
+# upset other devices on the TV, even on SteamOS).
+NO_PRESELECT=(boot cec)
 
 declare -A LABEL=(
     [gaming]="SteamOS conversion: boot into gaming mode, Steam on the desktop"
@@ -22,6 +23,7 @@ declare -A LABEL=(
     [glyphs]="Install Steam Deck/Machine icons: Deck button icons in gaming mode"
     [single]="Single user mode: no password, lock screen or log out (SDDM)"
     [launcher]="Steamify shortcut: desktop icon to run this again"
+    [cec]="HDMI-CEC: use Steam with the TV remote, TV on/off with the PC (experimental)"
     [machine]="Steam Machine support: LED bar driver, hardware settings in Steam"
     [kpin]="Pin the kernel to $PINNED_KERNEL_VER (fixes rebooting after shutdown)"
     [bios]="Update BIOS"

lib/steam-machine.sh

@@ -344,6 +344,7 @@ kernel_overview() {
         fi
         echo -e "  ${running}${line}"
     done
+    cec_status && { echo; echo -e "    $(cec_overview)"; }
     if [[ "$leds" == true ]]; then
         local loaded="$miss" nodes
         lsmod | grep -q '^leds_valve' && loaded="$mark"

steamify.sh

@@ -15,11 +15,11 @@
 set -uo pipefail
 
 # Release version, see CHANGELOG.md.
-VERSION=1.0.0
+VERSION=1.1.0
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 
-for lib in common state packages login-manager single-user steam-desktop steam-machine boot-session vapor-theme steamos-extras bios desktop-shortcut wizard-shortcut menu; do
+for lib in common state packages login-manager single-user steam-desktop steam-machine cec boot-session vapor-theme steamos-extras bios desktop-shortcut wizard-shortcut menu; do
     # shellcheck source=/dev/null
     source "$SCRIPT_DIR/lib/$lib.sh"
 done