From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9B5EBC07E85 for ; Sun, 9 Dec 2018 22:08:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6A29F20661 for ; Sun, 9 Dec 2018 22:08:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6A29F20661 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728033AbeLIWIK (ORCPT ); Sun, 9 Dec 2018 17:08:10 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:37288 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726948AbeLIWID (ORCPT ); Sun, 9 Dec 2018 17:08:03 -0500 Received: from pub.yeoldevic.com ([81.174.156.145] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gW73N-0002ir-VC; Sun, 09 Dec 2018 21:55:58 +0000 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gW72a-0003Gq-5r; Sun, 09 Dec 2018 21:55:08 +0000 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Bartlomiej Zolnierkiewicz" , "Mikulas Patocka" Date: Sun, 09 Dec 2018 21:50:33 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 059/328] udlfb: fix display corruption of the last line In-Reply-To: X-SA-Exim-Connect-IP: 81.174.156.145 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.62-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Mikulas Patocka commit 4e705e17ce3409a1f492cfd5dadcf6a4f6075842 upstream. The displaylink hardware has such a peculiarity that it doesn't render a command until next command is received. This produces occasional corruption, such as when setting 22x11 font on the console, only the first line of the cursor will be blinking if the cursor is located at some specific columns. When we end up with a repeating pixel, the driver has a bug that it leaves one uninitialized byte after the command (and this byte is enough to flush the command and render it - thus it fixes the screen corruption), however whe we end up with a non-repeating pixel, there is no byte appended and this results in temporary screen corruption. This patch fixes the screen corruption by always appending a byte 0xAF at the end of URB. It also removes the uninitialized byte. Signed-off-by: Mikulas Patocka Signed-off-by: Bartlomiej Zolnierkiewicz [bwh: Backported to 3.16: - Pointers to struct dlfb_data are named "dev" rather than "dlfb" - s/BPP/bpp/ Signed-off-by: Ben Hutchings --- drivers/video/fbdev/udlfb.c | 30 ++++++++++++++++++++---------- 1 file changed, 20 insertions(+), 10 deletions(-) --- a/drivers/video/fbdev/udlfb.c +++ b/drivers/video/fbdev/udlfb.c @@ -29,6 +29,7 @@ #include #include #include +#include #include