Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1767592Ab2KOLfY (ORCPT ); Thu, 15 Nov 2012 06:35:24 -0500 Received: from eu1sys200aog117.obsmtp.com ([207.126.144.143]:60164 "EHLO eu1sys200aog117.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2993197Ab2KOLfX (ORCPT ); Thu, 15 Nov 2012 06:35:23 -0500 Message-ID: <50A4D362.5060402@stericsson.com> Date: Thu, 15 Nov 2012 17:04:58 +0530 From: Rajanikanth HV Organization: st.com User-Agent: Mozilla/5.0 (X11; Linux i686; rv:16.0) Gecko/20121028 Thunderbird/16.0.2 MIME-Version: 1.0 To: Francesco Lavra Cc: Rajanikanth H V , "rob.herring@calxeda.com" , "lee.jones@linaro.org" , "arnd@arndb.de" , "anton.vorontsov@linaro.org" , Linus WALLEIJ , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "linaro-dev@lists.linaro.org" , "patches@linaro.org" , STEricsson_nomadik_linux Subject: Re: [PATCH 1/4] mfd: ab8500: add devicetree support for fuelgauge References: <1351698033-8980-1-git-send-email-rajanikanth.hv@linaro.org> <1351698033-8980-2-git-send-email-rajanikanth.hv@linaro.org> <509291FF.6090500@gmail.com> <509E8694.7080609@gmail.com> In-Reply-To: <509E8694.7080609@gmail.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1680 Lines: 41 On Saturday 10 November 2012 10:23 PM, Francesco Lavra wrote: >>> I don't get the point of declaring the char array and copying the string >>> in it, when you could simply use just the pointer returned by >>> of_get_property(). >> >> I am considering a corner case where in 'battery-type' property is not >> present and battery is connected.In this case i promote battery to >> UNKNOWN from null. > > You could achieve the same result without using the char array, with > this assignment: > > btech = "UNKNOWN"; > >> FYI: Further, btemp driver will identify the connected battery based on >> resistance value and decide to use. >> Ref: ab8500_btemp_id(...) ab8500_btemp.c >> >>> Anyway, if the string property is longer than 8 characters, you are >>> writing past the size of the destination array. >> >> i believe it is safe as power_supply.h comprises defines having battery >> technology type in 4 characters length which is normally the case and >> 7 chars length being "UNKNOWN" seldom referred > > You should be able to handle whatever the device tree contains, and if > it contains unexpected data this is not a good excuse for locking up the > system. agreed, if we were to go by what device tree contains then explicit assignment for battery type as "UNKNOWN" is not required, hence only 2 use case persist as : a) property name with one of the said value be present (as per documentation) b) property name not present -- 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/