From mboxrd@z Thu Jan 1 00:00:00 1970 From: marex@denx.de (Marek Vasut) Date: Sat, 1 Feb 2014 23:56:45 +0100 Subject: imx-drm: screen flickering In-Reply-To: <20140130074526.GQ16215@pengutronix.de> References: <201401291553.15040.marex@denx.de> <20140130074526.GQ16215@pengutronix.de> Message-ID: <201402012356.45736.marex@denx.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thursday, January 30, 2014 at 08:45:26 AM, Sascha Hauer wrote: > On Wed, Jan 29, 2014 at 03:53:14PM +0100, Marek Vasut wrote: > > On Wednesday, January 29, 2014 at 12:15:57 PM, Sascha Hauer wrote: > > > Hi Christian, > > > > > > On Tue, Jan 28, 2014 at 09:11:32AM +0100, Christian Gmeiner wrote: > > > > Hi all. > > > > > > > > From time to time it happens that my LVDS display is flickering (look > > > > at scroll bar in the video). > > > > https://drive.google.com/file/d/0B_fznDimUHVubWtvVFlMTkdBbUU/edit?usp > > > > =sha ring > > > > > > > > I really want to find the root cause of it, but I do not know where > > > > to start. I can trigger this > > > > sometimes after xscreensever "blanks" the screen and the screensafer > > > > gets disabled > > > > via user input. > > > > > > > > Any hints? > > > > > > Sorry, no idea. Philipp and me watched the video, but we both haven't > > > seen something like this before. > > > > Isn't it the clock polarity being inverted thing again [1]? > > Could be, at least the result should look similar. I just wonder why it > only happens after a few times doing something. I would expect the clock > is always inverted then. I actually noticed a rather strange behavior when the clock polarity was inverted as well. The flicker was not always there in my case either, but I used parallel LCD . Best regards, Marek Vasut