From 9e4afcd68cd0c57425c19de2b8d9dca61d459fc4 Mon Sep 17 00:00:00 2001
From: grawis <a0902110331@gmail.com>
Date: Fri, 12 Jun 2026 17:27:35 +0800
Subject: [PATCH] reject format changes while buffers are allocated

---
 device.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/device.c b/device.c
index aa8042a..92cad22 100644
--- a/device.c
+++ b/device.c
@@ -187,6 +187,9 @@ static int vcam_s_fmt_vid_cap(struct file *file,
 
     struct vcam_device *dev = (struct vcam_device *) video_drvdata(file);
 
+    if (vb2_is_busy(&dev->vb_out_vidq))
+        return -EBUSY;
+
     ret = vcam_try_fmt_vid_cap(file, priv, f);
     if (ret < 0)
         return ret;