From a8f80409b06a39605aadaaf64bdbf71b31d463ca Mon Sep 17 00:00:00 2001
From: Simon Glass <sjg@chromium.org>
Date: Thu, 1 Jun 2023 10:22:36 -0600
Subject: [PATCH] console: Correct truetype spacing error

The putc_xy() method is supposed to return the amount of space used. The
existing implementation erroneously adds the previous sub-pixel position
to the returned value. This spaces out the characters very slightly more
than it should. It is seldom noticeable but it does make accurate
measurement of the text impossible.

Fix this minor but long-standing bug.

Fixes: a29b012037c ("video: Add a console driver that uses TrueType fonts")

Signed-off-by: Simon Glass <sjg@chromium.org>
---
 drivers/video/console_truetype.c | 2 +-
 test/dm/video.c                  | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/video/console_truetype.c b/drivers/video/console_truetype.c
index 63d7557c71..6f3fc82f9b 100644
--- a/drivers/video/console_truetype.c
+++ b/drivers/video/console_truetype.c
@@ -256,7 +256,7 @@ static int console_truetype_putc_xy(struct udevice *dev, uint x, uint y,
 	 */
 	x_shift = xpos - (double)tt_floor(xpos);
 	xpos += advance * met->scale;
-	width_frac = (int)VID_TO_POS(xpos);
+	width_frac = (int)VID_TO_POS(advance * met->scale);
 	if (x + width_frac >= vc_priv->xsize_frac)
 		return -EAGAIN;
 
diff --git a/test/dm/video.c b/test/dm/video.c
index 30778157d9..6d9c55c140 100644
--- a/test/dm/video.c
+++ b/test/dm/video.c
@@ -556,7 +556,7 @@ static int dm_test_video_truetype(struct unit_test_state *uts)
 	ut_assertok(video_get_nologo(uts, &dev));
 	ut_assertok(uclass_get_device(UCLASS_VIDEO_CONSOLE, 0, &con));
 	vidconsole_put_string(con, test_string);
-	ut_asserteq(12237, compress_frame_buffer(uts, dev));
+	ut_asserteq(12187, compress_frame_buffer(uts, dev));
 
 	return 0;
 }
@@ -577,7 +577,7 @@ static int dm_test_video_truetype_scroll(struct unit_test_state *uts)
 	ut_assertok(video_get_nologo(uts, &dev));
 	ut_assertok(uclass_get_device(UCLASS_VIDEO_CONSOLE, 0, &con));
 	vidconsole_put_string(con, test_string);
-	ut_asserteq(35030, compress_frame_buffer(uts, dev));
+	ut_asserteq(34481, compress_frame_buffer(uts, dev));
 
 	return 0;
 }
@@ -598,7 +598,7 @@ static int dm_test_video_truetype_bs(struct unit_test_state *uts)
 	ut_assertok(video_get_nologo(uts, &dev));
 	ut_assertok(uclass_get_device(UCLASS_VIDEO_CONSOLE, 0, &con));
 	vidconsole_put_string(con, test_string);
-	ut_asserteq(29018, compress_frame_buffer(uts, dev));
+	ut_asserteq(29579, compress_frame_buffer(uts, dev));
 
 	return 0;
 }
-- 
2.39.5