From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Hilman Subject: Re: context_loss_count error value Date: Wed, 18 May 2011 12:50:58 +0200 Message-ID: <87k4douvsd.fsf@ti.com> References: <1305704452.1834.12.camel@deskari> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from na3sys009aog102.obsmtp.com ([74.125.149.69]:55624 "EHLO na3sys009aog102.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932638Ab1ERKvM (ORCPT ); Wed, 18 May 2011 06:51:12 -0400 Received: by mail-wy0-f169.google.com with SMTP id 19so1141643wyf.28 for ; Wed, 18 May 2011 03:51:11 -0700 (PDT) In-Reply-To: <1305704452.1834.12.camel@deskari> (Tomi Valkeinen's message of "Wed, 18 May 2011 10:40:52 +0300") Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Tomi Valkeinen Cc: linux-omap@vger.kernel.org Tomi Valkeinen writes: > Hi Kevin, > > I was fixing DSS context loss handling which is a bit broken, and while > testing on OMAP3 Overo, with -rc7 and omap2plus_defconfig, I noticed > that get_context_loss_count() seems to always return 0. > > 0 should be returned when an error happens, and as far as I see in > pwrdm_get_context_loss_count(), no error is happening but the DSS > context has just never been lost and the returned count is thus 0. > > Is this correct? And what happens when the count wraps and goes back to > zero, does the function return 0 in that case? Hmm, you're right. zero is actually documented as the error return value (even though it's not really checked.) Since driver's should only every care about the *difference* in value between two calls to context_loss_count(), this might not be a big deal, but a proper fix is probably to have the state counters start at one. Kevin