From 3427788c40617e0e5e36a083d7efe3358d4cd291 Mon Sep 17 00:00:00 2001
From: liang zhou <liang.zhou@gehealthcare.com>
Date: Fri, 15 May 2026 13:51:59 +0800
Subject: [PATCH] libweston: add API to find weston output by head serial

Add new API weston_compositor_find_output_by_head_serial for touch
binding.

Signed-off-by: liang zhou <liang.zhou@gehealthcare.com>
---
 include/libweston/libweston.h |  4 ++++
 libweston/compositor.c        | 26 ++++++++++++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/include/libweston/libweston.h b/include/libweston/libweston.h
index d97bd8399..f65460fd1 100644
--- a/include/libweston/libweston.h
+++ b/include/libweston/libweston.h
@@ -2936,6 +2936,10 @@ weston_compositor_get_touch_devices(struct weston_compositor *compositor);
 void
 weston_touch_device_list_release(struct weston_touch_device_list *list);
 
+struct weston_output *
+weston_compositor_find_output_by_head_serial(struct weston_compositor *compositor,
+					      const char *serial);
+
 #ifdef  __cplusplus
 }
 #endif
diff --git a/libweston/compositor.c b/libweston/compositor.c
index 76a4f4ed4..78e920661 100644
--- a/libweston/compositor.c
+++ b/libweston/compositor.c
@@ -11324,3 +11324,29 @@ weston_touch_device_list_release(struct weston_touch_device_list *list)
 	list->len = 0;
 	list->array = NULL;
 }
+
+/**
+ * Find an output by its head serial number
+ * \param compositor Weston compositor object
+ * \param serial Serial number of the head
+ * \return Output; NULL if not found
+ *
+ * \ingroup compositor
+ */
+WL_EXPORT struct weston_output *
+weston_compositor_find_output_by_head_serial(struct weston_compositor *compositor,
+					      const char *serial)
+{
+	struct weston_output *output;
+	struct weston_head *head;
+
+	/* Check active outputs */
+	wl_list_for_each(output, &compositor->output_list, link) {
+		wl_list_for_each(head, &output->head_list, output_link) {
+			if (head->serial_number && strcmp(head->serial_number, serial) == 0)
+				return output;
+		}
+	}
+
+	return NULL;
+}