Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933199Ab2JDNxs (ORCPT ); Thu, 4 Oct 2012 09:53:48 -0400 Received: from mail-ob0-f174.google.com ([209.85.214.174]:42759 "EHLO mail-ob0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933108Ab2JDNxr (ORCPT ); Thu, 4 Oct 2012 09:53:47 -0400 MIME-Version: 1.0 In-Reply-To: <506D3704.4060102@ti.com> References: <1349246100-7477-1-git-send-email-prabhakar.lad@ti.com> <506C158D.4000906@ti.com> <506D3704.4060102@ti.com> From: Prabhakar Lad Date: Thu, 4 Oct 2012 19:23:26 +0530 Message-ID: Subject: Re: [PATCH] ARM: davinci: dm644x: fix out range signal for ED To: Sekhar Nori Cc: DLOS , Manjunath Hadli , VGER , LAK , "Lad, Prabhakar" Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1919 Lines: 50 Sekhar On Thu, Oct 4, 2012 at 12:43 PM, Sekhar Nori wrote: > On 10/4/2012 10:22 AM, Prabhakar Lad wrote: >> Hi Sekhar, >> >> On Wed, Oct 3, 2012 at 4:08 PM, Sekhar Nori wrote: >>> On 10/3/2012 12:05 PM, Prabhakar wrote: >>>> From: Lad, Prabhakar >>>> >>>> while testing display on dm644x, for ED out-range signals >>>> was observed. This patch fixes appropriate clock setting >>>> for ED. >>> >>> Can you please clarify what you mean by "out range signal"? Are there >>> any user visible artifacts on the display? What was the clock being >>> provided earlier and what is the value after this patch? >>> >>> Also, is the issue severe enough that this patch should be applied to >>> stable tree as well? >>> >> Ideally a clock of 54Mhz is required for enhanced definition to >> work, which it was actually set to but while testing I noticed >> out-of-range signal. The out-of-range signal is often caused >> when the field rate is above the rate that the television will handle. >> When this is the case the TV or monitor displays "Out-Of-Range Signal". >> >> Reducing the clock fixed it. now the clock is set to 27Mhz. > > So, is the requirement for ED 54MHz or lower? Still trying to explain > myself how 27MHz is working where a 54MHz is required. I guess there is > also a lower limit on what the frequency should be? > Ideally its 54Mhz, but I see in the datasheet for AD7342/3 [1] it can also work at 27Mhz too. Regards, --Prabhakar [1] http://www.analog.com/static/imported-files/data_sheets/ADV7342_7343.pdf > Sorry I am not familiar will all the video concepts, hence the questions. > > Thanks, > Sekhar -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/