From 52ec8abc448771990ce535d6eb3ab70728b0f387 Mon Sep 17 00:00:00 2001
From: Morgan <me@morgan.kr>
Date: Thu, 4 Dec 2025 11:20:38 +0900
Subject: [PATCH] logind: fetch initial button state when device is registered
 late

If buttons that are not initialized from startup due to still
being processed by udev, the initial state is not checked.
---
 src/login/logind-core.c | 56 +++++++++++++++++++++++++----------------
 src/login/logind.c      | 12 +++++++--
 src/login/logind.h      |  2 +-
 3 files changed, 46 insertions(+), 24 deletions(-)

diff --git a/src/login/logind-core.c b/src/login/logind-core.c
index 1d88ec9661..3b62eafe52 100644
--- a/src/login/logind-core.c
+++ b/src/login/logind-core.c
@@ -328,8 +328,8 @@ int manager_process_seat_device(Manager *m, sd_device *d) {
         return 0;
 }
 
-int manager_process_button_device(Manager *m, sd_device *d) {
-        const char *sysname;
+int manager_process_button_device(Manager *m, sd_device *d, Button **ret_button) {
+        const char *sysname, *sn;
         Button *b;
         int r;
 
@@ -340,29 +340,43 @@ int manager_process_button_device(Manager *m, sd_device *d) {
                 return r;
 
         if (device_for_action(d, SD_DEVICE_REMOVE) ||
-            sd_device_has_current_tag(d, "power-switch") <= 0)
+            sd_device_has_current_tag(d, "power-switch") <= 0) {
 
                 button_free(hashmap_get(m->buttons, sysname));
-
-        else {
-                const char *sn;
-
-                r = manager_add_button(m, sysname, &b);
-                if (r < 0)
-                        return r;
-
-                r = device_get_seat(d, &sn);
-                if (r < 0)
-                        return r;
-
-                button_set_seat(b, sn);
-
-                r = button_open(b);
-                if (r < 0) /* event device doesn't have any keys or switches relevant to us? (or any other error
-                            * opening the device?) let's close the button again. */
-                        button_free(b);
+                goto no_match;
         }
 
+        b = hashmap_get(m->buttons, sysname);
+        if (b)
+                goto no_match;
+
+        r = manager_add_button(m, sysname, &b);
+        if (r < 0)
+                return r;
+
+        r = device_get_seat(d, &sn);
+        if (r < 0)
+                return r;
+
+        button_set_seat(b, sn);
+
+        r = button_open(b);
+        if (r < 0) {
+                /* event device doesn't have any keys or switches relevant to us? (or any other error
+                 * opening the device?) let's close the button again. */
+                button_free(b);
+                goto no_match;
+        }
+
+        if (ret_button)
+                *ret_button = b;
+
+        return 1;
+
+no_match:
+        if (ret_button)
+                *ret_button = NULL;
+
         return 0;
 }
 
diff --git a/src/login/logind.c b/src/login/logind.c
index 5cdfc2a00d..62757cabf0 100644
--- a/src/login/logind.c
+++ b/src/login/logind.c
@@ -236,7 +236,7 @@ static int manager_enumerate_buttons(Manager *m) {
         FOREACH_DEVICE(e, d) {
                 if (device_is_processed(d) <= 0)
                         continue;
-                RET_GATHER(r, manager_process_button_device(m, d));
+                RET_GATHER(r, manager_process_button_device(m, d, /* ret_button= */ NULL));
         }
 
         return r;
@@ -739,10 +739,18 @@ static int manager_dispatch_vcsa_udev(sd_device_monitor *monitor, sd_device *dev
 
 static int manager_dispatch_button_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
         Manager *m = ASSERT_PTR(userdata);
+        Button *b;
+        int r;
 
         assert(device);
 
-        manager_process_button_device(m, device);
+        r = manager_process_button_device(m, device, &b);
+        if (r < 0)
+                return 0;
+
+        if (r > 0)
+                (void) button_check_switches(b);
+
         return 0;
 }
 
diff --git a/src/login/logind.h b/src/login/logind.h
index 332a59f6da..4e3c15de52 100644
--- a/src/login/logind.h
+++ b/src/login/logind.h
@@ -153,7 +153,7 @@ int manager_add_user_by_uid(Manager *m, uid_t uid, User **ret_user);
 int manager_add_inhibitor(Manager *m, const char* id, Inhibitor **ret_inhibitor);
 
 int manager_process_seat_device(Manager *m, sd_device *d);
-int manager_process_button_device(Manager *m, sd_device *d);
+int manager_process_button_device(Manager *m, sd_device *d, Button **ret_button);
 
 int manager_spawn_autovt(Manager *m, unsigned vtnr);