pkgs/by-name/ed/edido/edido.sh

   1 #!/usr/bin/env bash
   2 set -eEuo pipefail
   3 test -z "${DEBUG:-}" || set -x
   4 set -eEuo pipefail
   5
   6 FIRMWARE_PATH="${EDID_PATH:-"/run/current-system/firmware"}"
   7 mapfile -t edid_paths <<<"${FIRMWARE_PATH//":"/$'\n'}"
   8
   9 err() {
  10   LOGGER="ERROR" log "$@"
  11   return 1
  12 }
  13
  14 log() {
  15   # shellcheck disable=SC2059
  16   printf "[${LOGGER:-"INFO"}] $1\n" "${@:2}" >&2
  17 }
  18
  19 find_path() {
  20   local filePath="$1"
  21   mapfile -t candidates < <(
  22     set -x
  23     find -L "${@:2}" -path "*/${filePath}"
  24   )
  25   if test "${#candidates[@]}" -eq 0; then
  26     log "'%s' path not found" "${filePath}"
  27     return 1
  28   fi
  29   log "'%s' path found at %s" "${filePath}" "${candidates[0]}"
  30   echo -n "${candidates[0]}"
  31 }
  32
  33 wait_for_file() {
  34   local filePath="$1"
  35   until find_path "${filePath}" "${@:2}"; do
  36     backoff "${filePath}"
  37   done
  38 }
  39
  40 backoff() {
  41   local what="$1" sleepFor
  42
  43   backoff_start="${backoff_start:-"5"}"
  44   backoff_current="${backoff_current:-"${backoff_start}"}"
  45   backoff_jitter_multiplier="${backoff_jitter_multiplier:-"0.3"}"
  46   backoff_multiplier="${backoff_multiplier:-1.5}"
  47
  48   sleepFor="$(bc <<<"${backoff_current} + ${RANDOM} % (${backoff_current} * ${backoff_jitter_multiplier})")"
  49
  50   log "still waiting for '%s', retry in %s sec..." "${what}" "${sleepFor}"
  51   sleep "${sleepFor}"
  52   backoff_current="$(bc <<<"scale=2; ${backoff_current} * ${backoff_multiplier}")"
  53
  54 }
  55
  56 force_mode() {
  57   local connPath="$1" newMode="$2" currentMode
  58   currentMode="$(cat "$connPath/force")"
  59   if test "${currentMode}" == "${newMode}"; then
  60     log "video mode is already '%s'" "${currentMode}"
  61     return
  62   fi
  63   log "changing video mode from '%s' to '%s'" "${currentMode}" "${newMode}"
  64   echo "${newMode}" >"$connPath/force"
  65   CHANGED=1
  66 }
  67
  68 force_edid() {
  69   local connPath="$1" edidPath="$2"
  70 }
  71
  72 apply_mode() {
  73   local connPath="$1" mode="$2"
  74   test -n "$mode" || return
  75   log "setting up fb mode..."
  76
  77   # see https://github.com/torvalds/linux/blob/8cd26fd90c1ad7acdcfb9f69ca99d13aa7b24561/drivers/gpu/drm/drm_sysfs.c#L202-L207
  78   # see https://docs.kernel.org/fb/modedb.html
  79   case "${mode}" in
  80   *d) force_mode "$connPath" off ;;
  81   *e) force_mode "$connPath" on ;;
  82   *D) force_mode "$connPath" on-digital ;;
  83   esac
  84 }
  85
  86 apply_edid() {
  87   local connPath="$1" edidFilename="$2" edidPath
  88   test -n "${edidFilename}" || return
  89   log "loading EDID override..."
  90   edidPath="$(find_path "${edidFilename}" "${edid_paths[@]/%/"/"}" -maxdepth 2)"
  91
  92   force_edid "${connPath}" "$edidPath"
  93   cat "$edidPath" >"${connPath}/edid_override"
  94
  95   if cmp "${connPath}/edid_override" "${edidPath}" &>/dev/null; then
  96     log "EDID is already up to date with '%s'" "${edidPath}"
  97   else
  98     log "applying EDID override from ${edidPath}"
  99     cat "$edidPath" >"${connPath}/edid_override"
 100     CHANGED=1
 101   fi
 102 }
 103
 104 load() {
 105   local conn="$1" edidFilename="$2" mode="$3"
 106   export LOGGER="$conn:${edidFilename}:$mode"
 107   CHANGED="${CHANGED:-0}"
 108
 109   log "starting configuration"
 110   local connPath
 111   connPath="$(wait_for_file "$conn" /sys/kernel/debug/dri/ -maxdepth 2 -type d)"
 112   apply_edid "${connPath}" "${edidFilename}"
 113   apply_mode "${connPath}" "$mode"
 114
 115   if test "${CHANGED}" != 0; then
 116     log "changes detected, triggering hotplug"
 117     echo 1 >"${connPath}/trigger_hotplug"
 118   else
 119     log "no changes detected, skipping hotplug trigger"
 120   fi
 121 }
 122
 123 main() {
 124   if [[ $EUID -ne 0 ]]; then
 125     err "must be run as root"
 126   fi
 127
 128   if test "$#" == 0; then
 129     log "loading kernel parameters from /proc/cmdline"
 130     # replace script arguments with kernel parameters
 131     mapfile -t args < <(xargs -n1 </proc/cmdline)
 132   else
 133     log "loading kernel parameters compatible arguments from commandline"
 134     args=("$@")
 135   fi
 136
 137   local -A edids modes connectors
 138   local -a entries
 139   local key value
 140
 141   for arg in "${args[@]}"; do
 142     key="${arg%%=*}"
 143     value=""
 144     test "${key}" == "${arg}" || value="${arg#*=}"
 145
 146     case "${key}" in
 147     video)
 148       # one argument per connector:
 149       #   video=DP-4:e video=DP-1:e
 150       connector="${value%:*}"
 151       mode="${value#*:}"
 152       connectors["${connector}"]=""
 153       modes["$connector"]="$mode"
 154       ;;
 155     drm.edid_firmware)
 156       # single argument for all connectors:
 157       #   drm.edid_firmware=DP-4:edid/one.bin,DP-1:edid/two.bin
 158       mapfile -t entries <<<"${value//","/$'\n'}"
 159       for entry in "${entries[@]}"; do
 160         connector="${entry%:*}"
 161         edidFilename="${entry#*:}"
 162         connectors["${connector}"]=""
 163         edids["${connector}"]="${edidFilename}"
 164       done
 165       ;;
 166     esac
 167   done
 168
 169   for connector in "${!connectors[@]}"; do
 170     # spawn in a subshell to easily adjust and runtime modify global variables
 171     (load "${connector}" "${edids["${connector}"]:-""}" "${modes["${connector}"]:-""}") &
 172   done
 173   wait
 174 }
 175
 176 main "$@"