#!/bin/sh
# recover-output-after-resume -- clear a post-resume eDP page-flip stall.
#
# Symptom (see journalctl --user --since -5m | grep 'Atomic commit failed'):
#   [wlr] backend/drm/atomic.c:82 connector eDP-1: Atomic commit failed:
#         Device or resource busy
#   [sway] desktop/output.c:307 Page-flip failed on output eDP-1
# ...repeatedly for tens of minutes after a resume.
#
# HISTORY: this was originally a workaround for the old ThinkPad's
# /etc/modprobe.d/i915.conf, which forced PSR2 and the deepest display C-states
# (options i915 enable_guc=3 enable_psr=2 enable_dc=4 enable_rc6=1 -- both of
# which taint the kernel). With PSR2 forced on, the flip pending across suspend
# never completed, so every later commit returned EBUSY, and DPMS "power on"
# alone did not clear it -- only a full modeset did.
#
# STATUS: that file is gone. This machine is a Framework Laptop 13 Pro whose
# iGPU is driven by `xe` (Panther Lake has no i915 support at all), so the
# original cause cannot recur. The modeset below is therefore CONDITIONAL and
# only fires when the stall is actually present in the journal.
#
# Why conditional: an unconditional disable/enable plus `shikanectl reload`
# after every resume is exactly the sequence that re-triggers the shikane
# 1.1.1 VariantInProgress deadlock (see shikane-watchdog.sh). No point paying
# that risk on resumes that are already healthy.
#
# Lid-aware on purpose: a blind `output eDP-1 enable` raced shikane's
# "External Display" profile (which keeps eDP-1 off) and caused
# "Atomic commit failed: Device or resource busy" churn in clamshell mode.
# See the note in clamshell-mode.sh.

set -u

LID_STATE="${LID_STATE:-/proc/acpi/button/lid/LID/state}"
OUTPUT="${OUTPUT:-eDP-1}"

# Always undo the idle DPMS-off first (this is what after_sleep_cmd used to do).
swaymsg "output * power on" 2>/dev/null

# Only escalate to a modeset if the page-flip stall is actually being reported.
# sway runs inside the user session, so its stderr is in the user journal.
if command -v journalctl >/dev/null 2>&1; then
    if ! journalctl --user --since '-3 min' --no-pager 2>/dev/null \
        | grep -qE 'Atomic commit failed|Page-flip failed on output'; then
        exit 0        # healthy resume -> do not disturb shikane
    fi
fi

# The modeset below is lid-gated only.
[ -r "$LID_STATE" ] || exit 0
grep -q 'open' "$LID_STATE" || exit 0   # lid closed -> leave layout to shikane

# Give the driver a moment to finish re-training the link before we modeset.
sleep 1
swaymsg "output $OUTPUT disable" 2>/dev/null
sleep 1
swaymsg "output $OUTPUT enable"  2>/dev/null
# Re-assert the shikane profile (mode/scale/position) on top of the modeset.
command -v shikanectl >/dev/null 2>&1 && shikanectl reload 2>/dev/null
exit 0