diff --git a/host_applications/linux/apps/gencmd/vcgencmd-completion-test.bats b/host_applications/linux/apps/gencmd/vcgencmd-completion-test.bats
new file mode 100755
index 000000000..9cfa095ef
--- /dev/null
+++ b/host_applications/linux/apps/gencmd/vcgencmd-completion-test.bats
@@ -0,0 +1,199 @@
+#!/usr/bin/env bats
+# Integration tests for vcgencmd command completion.
+# Runs on Raspberry Pi, requires bats-core package.
+
+load /usr/share/bash-completion/bash_completion || true
+load /usr/share/bash-completion/completions/vcgencmd
+
+
+complete_command() {
+  local cmd="$*"
+
+  COMP_LINE="${cmd}"
+  mapfile -t COMP_WORDS < <( compgen -W "${cmd}" )
+
+  # index of current word in $COMP_WORDS array
+  COMP_CWORD=$(( ${#COMP_WORDS[@]} - 1 ))
+  if [[ ${cmd: -1} == " " ]]; then
+    COMP_CWORD=$(( COMP_CWORD + 1 ))
+  fi
+
+  # current pointer position in line
+  COMP_POINT="${#cmd}"
+
+  # name of completion function
+  complete_func=$(complete -p "${COMP_WORDS[0]}" | sed 's/.*-F \([^ ]*\) .*/\1/')
+  [[ -n $complete_func ]]
+
+  # Run completion function. Sets the COMPREPLY array.
+  $complete_func "${COMP_WORDS[0]}" || true
+
+  if [[ $DEBUG_VCGENCMD_TEST ]]; then
+    echo >&3
+    echo "COMP_LINE='${COMP_LINE}'" >&3
+    echo "COMP_WORDS='${COMP_WORDS[*]}'" >&3
+    echo "length COMP_WORDS = ${#COMP_WORDS[@]}" >&3
+    echo "COMP_CWORD=${COMP_CWORD}" >&3
+    echo "COMP_POINT=${COMP_POINT}" >&3
+    echo "COMPREPLY=${COMPREPLY[*]}" >&3
+    echo "length COMPREPLY=${#COMPREPLY[@]}" >&3
+  fi
+}
+
+is_pi4() {
+  grep -qE '^Model.* Raspberry Pi 4' /proc/cpuinfo
+}
+
+@test "vcgencmd - -> -t -h --help" {
+  complete_command "vcgencmd -"
+  [[ "${COMPREPLY[*]}" == "-t -h --help" ]]
+}
+
+@test "--h -> --help" {
+  complete_command "vcgencmd --h"
+  [[ "${COMPREPLY[*]}" == "--help" ]]
+}
+
+@test "--help -> (nothing)" {
+  complete_command "vcgencmd --help "
+  [[ "${#COMPREPLY[@]}" -eq 0 ]]
+}
+
+@test "vcgencmd -xxx -> (nothing)" {
+  complete_command "vcgencmd -xxx "
+  [[ "${#COMPREPLY[@]}" -eq 0 ]]
+}
+
+@test "vcgencmd foobar -> (nothing)" {
+  complete_command "vcgencmd foobar "
+  [[ "${#COMPREPLY[@]}" -eq 0 ]]
+}
+
+@test "vcgencmd -> commands version get_config measure_temp ..." {
+  complete_command "vcgencmd "
+  [[ "${#COMPREPLY[@]}" -gt 60 ]]
+  echo "${COMPREPLY[*]}" | grep -Ewo "(commands|version|get_config|measure_temp)"
+}
+
+@test "vcgencmd -t -> commands version get_config measure_temp ..." {
+  complete_command "vcgencmd -t "
+  [[ "${#COMPREPLY[@]}" -gt 60 ]]
+  echo "${COMPREPLY[*]}" | grep -Ewo "(commands|version|get_config|measure_temp)"
+}
+
+@test "codec_enabled -> FLAC MJPG ..." {
+  complete_command "vcgencmd codec_enabled "
+  echo "${COMPREPLY[*]}" | grep -Ewo "(FLAC|MJPG|H263|PCM|VORB)"
+}
+
+@test "measure_clock -> arm core uart ..." {
+  complete_command "vcgencmd measure_clock "
+  echo "${COMPREPLY[*]}" | grep -Ewo "(arm|core|uart|hdmi)"
+}
+
+@test "measure_volts -> core sdram_[cip]" {
+  complete_command "vcgencmd measure_clock "
+  echo "${COMPREPLY[*]}" | grep -Ewo "(core|sdram_[cip])"
+}
+
+@test "get_mem -> arm gpu" {
+  complete_command "vcgencmd get_mem "
+  echo "${COMPREPLY[*]}" | grep -Ewo "(arm|gpu)"
+}
+
+@test "get_config -> int str arm_freq ..." {
+  complete_command "vcgencmd get_config "
+  [[ "${#COMPREPLY[@]}" -gt 30 ]]
+  echo "${COMPREPLY[*]}" | grep -Ewo "(int|str|device_tree|arm_freq|total_mem|hdmi_cvt:0|enable_tvout)"
+}
+
+@test "get_config hdmi_cvt: -> 0 1" {
+  complete_command "vcgencmd get_config hdmi_cvt:"
+  [[ "${COMPREPLY[*]}" == "0 1" ]]
+}
+
+# Pi 4B has two hdmi pixel freq limits 0 and 1, Pi 2 and 3 just have one
+@test "get_config hdmi_pixel_freq_li -> hdmi_pixel_freq_limit:0" {
+  if is_pi4; then
+    skip "test only valid with 1 hdmi (earlier pi models)"
+  fi
+  complete_command "vcgencmd get_config hdmi_pixel_freq_li"
+  [[ "${COMPREPLY[*]}" == "hdmi_pixel_freq_limit:0" ]]
+}
+
+@test "get_config hdmi_pixel_freq_li -> hdmi_pixel_freq_limit:" {
+  if ! is_pi4; then
+    skip "test requires Pi 4 with 2 hdmi outputs"
+  fi
+  complete_command "vcgencmd get_config hdmi_pixel_freq_li"
+  [[ "${COMPREPLY[*]}" == "hdmi_pixel_freq_limit:0 hdmi_pixel_freq_limit:1" ]]
+}
+
+@test "get_config hdmi_pixel_freq_limit: -> 0 1" {
+  if ! is_pi4; then
+    skip "test requires Pi 4 with 2 hdmi outputs"
+  fi
+  complete_command "vcgencmd get_config hdmi_pixel_freq_limit:"
+  [[ "${COMPREPLY[*]}" == "0 1" ]]
+}
+
+@test "vcos -> version log" {
+  complete_command "vcgencmd vcos "
+  echo "${COMPREPLY[*]}" | grep -Ewo "(version|log)"
+}
+
+@test "display_power -> 0 1 -1" {
+  complete_command "vcgencmd display_power "
+  [[ "${COMPREPLY[*]}" == "0 1 -1" ]]
+}
+
+@test "-t display_power -> 0 1 -1" {
+  complete_command "vcgencmd -t display_power "
+  [[ "${COMPREPLY[*]}" == "0 1 -1" ]]
+}
+
+@test "display_power [0, 1] -> 0 1 2 3 7" {
+  local display_nums="0 1 2 3 7"
+  complete_command "vcgencmd display_power 0 "
+  [[ "${COMPREPLY[*]}" == "$display_nums" ]]
+  complete_command "vcgencmd display_power 1 "
+  [[ "${COMPREPLY[*]}" == "$display_nums" ]]
+}
+
+@test "display_power -1 -> 0 1 2 3 7" {
+  local display_nums="0 1 2 3 7"
+  complete_command "vcgencmd display_power -1 "
+  [[ "${COMPREPLY[*]}" == "$display_nums" ]]
+}
+
+@test "BADARG display_power -1 -> (nothing)" {
+  complete_command "vcgencmd BADARG display_power -1 "
+  echo "${COMPREPLY[*]}"
+  [[ "${COMPREPLY[*]}" == "" ]]
+}
+
+@test "display_power BADARG -1 -> (nothing)" {
+  complete_command "vcgencmd display_power BADARG -1 "
+  echo "${COMPREPLY[*]}"
+  [[ "${COMPREPLY[*]}" == "" ]]
+}
+
+@test "-t display_power -1 -> 0 1 2 3 7" {
+  complete_command "vcgencmd -t display_power -1 "
+  [[ "${COMPREPLY[*]}" == "0 1 2 3 7" ]]
+}
+
+@test "vcos log -> status" {
+  complete_command "vcgencmd vcos log "
+  [[ "${COMPREPLY[*]}" == "status" ]]
+}
+
+@test "-t vcos log -> status" {
+  complete_command "vcgencmd -t vcos log "
+  [[ "${COMPREPLY[*]}" == "status" ]]
+}
+
+@test "vcos 0 -> (nothing)" {
+  complete_command "vcgencmd vcos 0 "
+  [[ "${#COMPREPLY[@]}" -eq 0 ]]
+}
diff --git a/host_applications/linux/apps/gencmd/vcgencmd-completion.bash b/host_applications/linux/apps/gencmd/vcgencmd-completion.bash
new file mode 100644
index 000000000..dd30e296b
--- /dev/null
+++ b/host_applications/linux/apps/gencmd/vcgencmd-completion.bash
@@ -0,0 +1,124 @@
+# vcgencmd(1) completion                                   -*- shell-script -*-
+
+_vcgencmd_commands()
+{
+    local commands fallback re
+    commands="$(/usr/bin/vcgencmd commands 2> /dev/null)"
+    fallback="codec_enabled commands display_power get_camera get_config
+        get_lcd_info get_mem get_throttled measure_temp measure_volts
+        mem_oom version"
+    re='commands="(.*)"'
+
+    if [[ $commands =~ $re ]]; then
+        commands="${BASH_REMATCH[1]}"
+        commands="${commands//,}"
+    else
+        commands="${fallback}"
+    fi
+
+    compgen -W "$commands" -- "$cur"
+}
+
+# This function counts the number of args, excluding options,
+# providing exceptions for option-like arguments.
+# @param $1 chars  Characters out of $COMP_WORDBREAKS which should
+#     NOT be considered word breaks. See __reassemble_comp_words_by_ref.
+# @param $2 non_opt_args arguments that look like options, but aren't
+_vcgencmd_count_args()
+{
+    local i cword words non_opt_args
+    __reassemble_comp_words_by_ref "$1" words cword
+
+    args=1
+    non_opt_args="$2"
+
+    for i in "${words[@]:1:cword-1}"; do
+        if [[ "$i" != -* ]]; then
+            args=$((args+1))
+        else
+            for a in $non_opt_args; do
+              [[ "$i" == "$a" ]] && args=$((args+1))
+            done
+        fi
+    done
+}
+
+_vcgencmd() {
+    local cur prev cword words opts='' args
+    _init_completion -n ':' || return
+    _vcgencmd_count_args ':' '-1'
+
+    if [[ $cword -eq 1 && $cur == -* ]] ; then
+        mapfile -t COMPREPLY < <( compgen -W '-t -h --help' -- "$cur" )
+        return 0
+    fi
+
+    if [[ $args -eq 1 ]]; then
+        case "$prev" in
+            -h|--help)
+                ;;
+            -t|vcgencmd)
+                mapfile -t COMPREPLY < <( _vcgencmd_commands )
+                ;;
+            -*)
+                ;;
+        esac
+        return 0
+    fi
+
+    if [[ $args -eq 2 ]]; then
+        case "$prev" in
+            codec_enabled)
+                opts='AGIF FLAC H263 H264 MJPA MJPB MJPG MPG2 MPG4 MVC0 PCM
+                    THRA VORB VP6 VP8 WMV9 WVC1'
+                ;;
+            measure_clock)
+                opts='arm core h264 isp v3d uart pwm emmc pixel vec hdmi dpi'
+                ;;
+            measure_volts)
+                opts='core sdram_c sdram_i sdram_p'
+                ;;
+            get_mem)
+                opts='arm gpu'
+                ;;
+            get_config)
+                opts='int str'
+                opts+=" $("$1" get_config str | command sed -e 's/=.*$//')"
+                opts+=" $("$1" get_config int | command sed -e 's/=.*$//')"
+                ;;
+            display_power)
+                opts='0 1 -1'
+                ;;
+            vcos)
+                opts='log version'
+                ;;
+        esac
+    fi
+
+    if [[ $args -eq 3 ]]; then
+        case "${words[cword - 2]}" in
+            display_power)
+                case "$prev" in
+                    0|1|-1)
+                        opts='0 1 2 3 7'
+                        ;;
+                esac
+                ;;
+            vcos)
+                case "$prev" in
+                    log)
+                        opts='status'
+                        ;;
+                esac
+                ;;
+        esac
+    fi
+
+    [[ -n $opts ]] && mapfile -t COMPREPLY < <( compgen -W "$opts" -- "$cur" )
+    [[ $prev == "get_config" ]] && __ltrim_colon_completions "$cur"
+
+    return 0
+} &&
+complete -F _vcgencmd vcgencmd
+
+# ex: filetype=sh