[3.5.y.z,extended,stable] Patch "video: mxsfb: fix crash when unblanking the display" has been added to staging queue

Message ID 1358288484-31066-1-git-send-email-herton.krzesinski@canonical.com
State New
Headers show

Commit Message

Herton Ronaldo Krzesinski Jan. 15, 2013, 10:21 p.m.
This is a note to let you know that I have just added a patch titled

    video: mxsfb: fix crash when unblanking the display

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:


If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see



From 12b012e4bbf85cfce419a2f9ede93b9db7ebf41e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lothar=20Wa=C3=9Fmann?= <LW@KARO-electronics.de>
Date: Thu, 22 Nov 2012 13:49:14 +0100
Subject: [PATCH] video: mxsfb: fix crash when unblanking the display
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

commit 6c1ecba8d84841277d68140ef485335d5be28485 upstream.

The VDCTRL4 register does not provide the MXS SET/CLR/TOGGLE feature.
The write in mxsfb_disable_controller() sets the data_cnt for the LCD
DMA to 0 which obviously means the max. count for the LCD DMA and
leads to overwriting arbitrary memory when the display is unblanked.

Signed-off-by: Lothar WaƟmann <LW@KARO-electronics.de>
Acked-by: Juergen Beisert <jbe@pengutronix.de>
Tested-by: Lauri Hintsala <lauri.hintsala@bluegiga.net>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
 drivers/video/mxsfb.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)



diff --git a/drivers/video/mxsfb.c b/drivers/video/mxsfb.c
index abbe691..fc2c4381 100644
--- a/drivers/video/mxsfb.c
+++ b/drivers/video/mxsfb.c
@@ -367,7 +367,8 @@  static void mxsfb_disable_controller(struct fb_info *fb_info)

-	writel(VDCTRL4_SYNC_SIGNALS_ON, host->base + LCDC_VDCTRL4 + REG_CLR);
+	reg = readl(host->base + LCDC_VDCTRL4);
+	writel(reg & ~VDCTRL4_SYNC_SIGNALS_ON, host->base + LCDC_VDCTRL4);