Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755350Ab1BVTvq (ORCPT ); Tue, 22 Feb 2011 14:51:46 -0500 Received: from opensource.wolfsonmicro.com ([80.75.67.52]:42188 "EHLO opensource2.wolfsonmicro.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754824Ab1BVTvp (ORCPT ); Tue, 22 Feb 2011 14:51:45 -0500 Date: Tue, 22 Feb 2011 19:51:43 +0000 From: Mark Brown To: john stultz Cc: Marcelo Roberto Jimenez , rtc-linux@googlegroups.com, LKML , Thomas Gleixner , Alessandro Zummo Subject: Re: [rtc-linux] [PATCH 04/10] RTC: Cleanup rtc_class_ops->read_alarm() Message-ID: <20110222195143.GC31611@opensource.wolfsonmicro.com> References: <1298332538-31216-1-git-send-email-john.stultz@linaro.org> <1298332538-31216-5-git-send-email-john.stultz@linaro.org> <20110222023452.GB18299@sirena.org.uk> <1298343333.4222.36.camel@work-vm> <1298362178.4222.57.camel@work-vm> <1298403310.9215.26.camel@work-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1298403310.9215.26.camel@work-vm> X-Cookie: You now have Asian Flu. User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1072 Lines: 24 On Tue, Feb 22, 2011 at 11:35:10AM -0800, john stultz wrote: > Yea. The way I thought about it originally was that you can set an alarm > and that alarm will fire if the machine is on, suspended or even in some > cases off. Then, when the machine is booted (system reset), the state > of the RTC's alarm should not be trusted. > Your description of the AIE/UIE having random values aligns with that > intuition. This seems rather worrying - it sounds like it might mean that the device might come up firing spuriously which doesn't seem terribly clever. > However, if the expectation is that once set, the alarm should persist > across any number of reboots, this makes it a bit more complicated. For an embedded device I'd expect that either nothing about the RTC would persist (including the time) or everything would. -- 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/