Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758977AbZLGIEs (ORCPT ); Mon, 7 Dec 2009 03:04:48 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757495AbZLGIEq (ORCPT ); Mon, 7 Dec 2009 03:04:46 -0500 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:58255 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752822AbZLGIEp (ORCPT ); Mon, 7 Dec 2009 03:04:45 -0500 Date: Mon, 7 Dec 2009 09:04:46 +0100 From: Pavel Machek To: Wu Zhangjin Cc: Ralf Baechle , akpm@linux-foundation.org, linux-mips@linux-mips.org, linux-kernel@vger.kernel.org, Dmitry Torokhov , "Rafael J . Wysocki" , zhangfx@lemote.com, linux-laptop@vger.kernel.org, Stephen Rothwell Subject: Re: [PATCH v8 5/8] Loongson: YeeLoong: add hardware monitoring driver Message-ID: <20091207080446.GB23088@elf.ucw.cz> References: <20091206084717.GD2766@ucw.cz> <1260147298.3126.2.camel@falcon.domain.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1260147298.3126.2.camel@falcon.domain.org> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 999 Lines: 33 > > What is going on here? I thought the value is already in two's > > complement... Is the above equivalent of > > > > if (value < 0) > > value = -value; > > > > ? If so, why? If not, can you add a comment? > > Right, then, will use this instead: > > static int get_battery_current(void) > { > s16 value; > > value = (ec_read(REG_BAT_CURRENT_HIGH) << 8) | > (ec_read(REG_BAT_CURRENT_LOW)); > > return abs(value); > } That's certainly better. But... why not return signed value? Current flowing from the battery is certainly very different from current flowing into it... Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- 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/