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# T2 SDE: package/*/xorg-server/hotfix-fbdevHWSetMode.patch
# Copyright (C) 2024 The T2 SDE Project
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Some Linux fb drivers, like sgi-o2 gbe update the mode struct to actually
constraint sync values. Actually inform the user about what changed, and
don't error out for unimportant sync details.

--- xorg-server-21.1.10/hw/xfree86/fbdevhw/fbdevhw.c.orig	2023-12-13 02:31:04.000000000 +0100
+++ xorg-server-21.1.10/hw/xfree86/fbdevhw/fbdevhw.c	2024-01-09 13:32:27.895682324 +0100
@@ -200,22 +200,50 @@
 }
 
 static Bool
-fbdev_modes_equal(struct fb_var_screeninfo *set, struct fb_var_screeninfo *req)
+fbdev_modes_equal(ScrnInfoPtr pScrn, struct fb_var_screeninfo *set, struct fb_var_screeninfo *req)
 {
-    return (set->xres_virtual >= req->xres_virtual &&
-            set->yres_virtual >= req->yres_virtual &&
-            set->bits_per_pixel == req->bits_per_pixel &&
-            set->red.length == req->red.length &&
-            set->green.length == req->green.length &&
-            set->blue.length == req->blue.length &&
-            set->xres == req->xres && set->yres == req->yres &&
-            set->right_margin == req->right_margin &&
-            set->hsync_len == req->hsync_len &&
-            set->left_margin == req->left_margin &&
-            set->lower_margin == req->lower_margin &&
-            set->vsync_len == req->vsync_len &&
-            set->upper_margin == req->upper_margin &&
-            set->sync == req->sync && set->vmode == req->vmode);
+    if (set->xres != req->xres || set->yres != req->yres) {
+	xf86DrvMsg(pScrn->scrnIndex, X_INFO, "fbdev_modes: res not equal\n");
+	return FALSE;
+    }
+
+    if (set->xres_virtual < req->xres_virtual || set->yres_virtual < req->yres_virtual) {
+	xf86DrvMsg(pScrn->scrnIndex, X_INFO, "fbdev_modes: virtual res not equal\n");
+	return FALSE;
+    }
+
+    if (set->sync != req->sync || set->vmode != req->vmode) {
+	xf86DrvMsg(pScrn->scrnIndex, X_INFO, "fbdev_modes: sync or vmode not equal\n");
+	return FALSE;
+    }
+
+    if (set->bits_per_pixel != req->bits_per_pixel) {
+	xf86DrvMsg(pScrn->scrnIndex, X_INFO, "fbdev_modes: bits per pixel not equal\n");
+	return FALSE;
+    }
+
+    if (set->red.length != req->red.length ||
+        set->green.length != req->green.length ||
+        set->blue.length != req->blue.length) {
+	xf86DrvMsg(pScrn->scrnIndex, X_INFO, "fbdev_modes: RGB lengths not equal\n");
+	return FALSE;
+    }
+
+    if (set->hsync_len != req->hsync_len ||
+        set->vsync_len != req->vsync_len) {
+	xf86DrvMsg(pScrn->scrnIndex, X_INFO, "fbdev_modes: sync not equal\n");
+	//return FALSE;
+    }
+
+    if (set->right_margin != req->right_margin ||
+        set->left_margin != req->left_margin ||
+        set->lower_margin != req->lower_margin ||
+        set->upper_margin != req->upper_margin) {
+	xf86DrvMsg(pScrn->scrnIndex, X_INFO, "fbdev_modes: margins not equal\n");
+	//return FALSE;
+    }
+
+    return TRUE;
 }
 
 static void
@@ -526,7 +526,7 @@
         return FALSE;
     }
 
-    if (!fbdev_modes_equal(&set_var, &req_var)) {
+    if (!fbdev_modes_equal(pScrn, &set_var, &req_var)) {
         if (!check)
             xf86DrvMsg(pScrn->scrnIndex, X_ERROR,
                        "FBIOPUT_VSCREENINFO succeeded but modified " "mode\n");