From 6c8f847ac1356387692f224b48c7a83ac5918b5d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= <marcandre.lureau@redhat.com>
Date: Sun, 27 Sep 2020 18:57:46 +0400
Subject: edid: fix physical display size computation
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Divide the resolution by the DPI, and multiply to mm.

Note the computation done for edid[21/22] is correct (in cm).

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20200927145751.365446-2-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 hw/display/edid-generate.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'hw/display/edid-generate.c')

diff --git a/hw/display/edid-generate.c b/hw/display/edid-generate.c
index e58472fde5..618c74e1df 100644
--- a/hw/display/edid-generate.c
+++ b/hw/display/edid-generate.c
@@ -208,8 +208,8 @@ static void edid_desc_timing(uint8_t *desc,
                              uint32_t dpi)
 {
     /* physical display size */
-    uint32_t xmm = xres * dpi / 254;
-    uint32_t ymm = yres * dpi / 254;
+    uint32_t xmm = xres * 254 / 10 / dpi;
+    uint32_t ymm = yres * 254 / 10 / dpi;
 
     /* pull some realistic looking timings out of thin air */
     uint32_t xfront = xres * 25 / 100;
-- 
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