From: Marko Kohtala <marko.kohtala@okoko.fi>
Date: Tue, 18 Jun 2019 07:41:08 +0000 (+0300)
Subject: video: ssd1307fb: Start page range at page_offset
X-Git-Tag: v3.16.79~68
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9bffc2e4f74756168b7f8a5ed67c8b667b34d23f;p=thirdparty%2Fkernel%2Fstable.git

video: ssd1307fb: Start page range at page_offset

commit dd9782834dd9dde3624ff1acea8859f3d3e792d4 upstream.

The page_offset was only applied to the end of the page range. This caused
the display updates to cause a scrolling effect on the display because the
amount of data written to the display did not match the range display
expected.

Fixes: 301bc0675b67 ("video: ssd1307fb: Make use of horizontal addressing mode")
Signed-off-by: Marko Kohtala <marko.kohtala@okoko.fi>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Michal Vokáč <michal.vokac@ysoft.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190618074111.9309-4-marko.kohtala@okoko.fi
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
index 0ea6345cabcac..729dd7cc92756 100644
--- a/drivers/video/fbdev/ssd1307fb.c
+++ b/drivers/video/fbdev/ssd1307fb.c
@@ -426,7 +426,7 @@ static int ssd1307fb_ssd1306_init(struct ssd1307fb_par *par)
 	if (ret < 0)
 		return ret;
 
-	ret = ssd1307fb_write_cmd(par->client, 0x0);
+	ret = ssd1307fb_write_cmd(par->client, par->page_offset);
 	if (ret < 0)
 		return ret;