From cf89b15573007d17917d1278dac4242d60a4dcef Mon Sep 17 00:00:00 2001
From: Brad Stein <Brad.Stein@gmail.com>
Date: Tue, 12 May 2026 14:31:23 -0300
Subject: [PATCH] audio: improve tethys uac recovery hints

---
 .../run_tethys_downstream_audio_sanity.sh     | 25 +++++++++++++++----
 ...tethys_downstream_audio_manual_contract.rs |  6 ++++-
 2 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/scripts/manual/run_tethys_downstream_audio_sanity.sh b/scripts/manual/run_tethys_downstream_audio_sanity.sh
index f41419d..8eca0d6 100755
--- a/scripts/manual/run_tethys_downstream_audio_sanity.sh
+++ b/scripts/manual/run_tethys_downstream_audio_sanity.sh
@@ -25,14 +25,28 @@ run_pactl() { timeout "${PULSE_TIMEOUT}s" pactl "$@"; }
 run_wpctl() { timeout "${PULSE_TIMEOUT}s" wpctl "$@"; }
 
 print_rebind_hint() {
-  local card iface driver
-  card=$(aplay -l 2>/dev/null | awk '/Lesavka|Composite|UAC2|USB Audio/ {if (match($0, /card [0-9]+/)) {print substr($0, RSTART + 5, RLENGTH - 5); exit}}' || true)
+  local card iface driver device_root audio_ifaces
+  card=$({
+    aplay -l 2>/dev/null | awk '/Lesavka|Composite|UAC2|USB Audio/ {if (match($0, /card [0-9]+/)) {print substr($0, RSTART + 5, RLENGTH - 5); exit}}'
+    awk '/Lesavka|Composite|UAC2|USB Device 0x1d6b:0x104|1d6b:0x104/ {print $1; exit}' /proc/asound/cards 2>/dev/null
+  } | awk 'NF {print; exit}' || true)
   if [[ -n ${card:-} && -e /sys/class/sound/card${card}/device ]]; then
     iface=$(basename "$(readlink -f "/sys/class/sound/card${card}/device")")
     driver=$(basename "$(readlink -f "/sys/class/sound/card${card}/device/driver" 2>/dev/null || true)")
-    if [[ -n $iface && -n $driver ]]; then
-      echo "Tethys root-level soft rebind, if the user audio graph is wedged:" >&2
-      echo "  sudo sh -c 'echo -n \"$iface\" > /sys/bus/usb/drivers/$driver/unbind; sleep 2; echo -n \"$iface\" > /sys/bus/usb/drivers/$driver/bind'" >&2
+    device_root=${iface%:*}
+    if [[ -n $iface && -n $driver && -n $device_root ]]; then
+      audio_ifaces=$(for candidate in "/sys/bus/usb/devices/${device_root}":*; do
+        [[ -e $candidate/bInterfaceClass && -e $candidate/bInterfaceSubClass ]] || continue
+        [[ $(cat "$candidate/bInterfaceClass" 2>/dev/null) == "01" ]] || continue
+        case "$(cat "$candidate/bInterfaceSubClass" 2>/dev/null)" in
+          01|02) basename "$candidate" ;;
+        esac
+      done | sort -V | xargs echo)
+      [[ -n $audio_ifaces ]] || audio_ifaces=$iface
+      echo "Tethys root-level audio-interface rebind, if the UAC graph is wedged:" >&2
+      echo "  sudo sh -c 'for i in $audio_ifaces; do echo -n \"\$i\" > /sys/bus/usb/drivers/$driver/unbind 2>/dev/null || true; done; sleep 2; for i in $audio_ifaces; do echo -n \"\$i\" > /sys/bus/usb/drivers/$driver/bind 2>/dev/null || true; done'" >&2
+      echo "Tethys full composite re-enumeration, if audio interfaces bind but ALSA creates no PCM:" >&2
+      echo "  sudo sh -c 'echo 0 > /sys/bus/usb/devices/$device_root/authorized; sleep 3; echo 1 > /sys/bus/usb/devices/$device_root/authorized'" >&2
     fi
   fi
 }
@@ -52,6 +66,7 @@ sink_line=$(run_pactl list short sinks | awk '/alsa_output\.usb-Lesavka|Lesavka|
 if [[ -z ${sink_line:-} ]]; then
   fail "no Lesavka USB speaker sink is visible to PipeWire/Pulse"
   run_pactl list short sinks >&2 || true
+  print_rebind_hint
   exit 1
 fi
 sink_name=$(awk '{print $2}' <<<"$sink_line")
diff --git a/tests/manual/audio/tethys_downstream_audio_manual_contract.rs b/tests/manual/audio/tethys_downstream_audio_manual_contract.rs
index ddb8f20..09a9bb1 100644
--- a/tests/manual/audio/tethys_downstream_audio_manual_contract.rs
+++ b/tests/manual/audio/tethys_downstream_audio_manual_contract.rs
@@ -36,7 +36,11 @@ fn tethys_audio_probe_keeps_repair_explicit_and_non_sudo_by_default() {
         "LESAVKA_TETHYS_AUDIO_REPAIR:-0",
         "LESAVKA_TETHYS_AUDIO_RESTART:-0",
         "restart Tethys user audio or replug/rebind",
-        "Tethys root-level soft rebind, if the user audio graph is wedged",
+        "Tethys root-level audio-interface rebind, if the UAC graph is wedged",
+        "bInterfaceSubClass",
+        "/proc/asound/cards",
+        "print_rebind_hint",
+        "Tethys full composite re-enumeration, if audio interfaces bind but ALSA creates no PCM",
     ] {
         assert!(
             SCRIPT.contains(expected),