From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean Delvare Date: Tue, 07 Oct 2008 20:16:32 +0000 Subject: Re: [lm-sensors] Looking for IT8720 datasheet. Message-Id: <20081007221632.0e5a8679@hyperion.delvare> List-Id: References: <79c9d4530810020825r79de9817g6933f6cab1d414c1@mail.gmail.com> In-Reply-To: <79c9d4530810020825r79de9817g6933f6cab1d414c1@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lm-sensors@vger.kernel.org On Fri, 03 Oct 2008 13:14:31 -0400, Frank Myhr wrote: > Jean-Marc Spaggiari wrote: > > When I force has_fan to 5 fans, I get: > > > > fan1: 3000 RPM (min = 0 RPM) > > fan2: 0 RPM (min = 0 RPM) > > fan3: 5973 RPM (min = 0 RPM) > > fan4: -1 RPM (min = -1 RPM) > > fan5: -1 RPM (min = -1 RPM) > > > > So can I just help him to read to pwm 4 and 5 correctly? > > The -1 values you're reporting for fan4 and fan5 come from > #define FAN16_FROM_REG(val) ((val)=0?-1:(val)=0xffff?0:1350000/((val)*2)) > > In other words, the 8720 reports "0", the above macro converts that to > -1. (I'm not entirely clear why this is done.) That's a legacy from the good ol' times. Old drivers tend to report missing fans, fan failures or impossible register values with a speed of -1. It never made any sense to me and many drivers report this condition as RPM = 0, with an optional fanN_fault file getting value 1 for detected fan failures. We have no clear standard for this yet so in practice every driver is free to report -1 or 0 for uncommon fan conditions. > > Regarding the resistors. should I publish the values? Or it's useless? > > I think it would help at least other users of your board. Perhaps add it > to Documentation/hwmon/it87 ? Best is to write a configuration file for the motherboard in question and publish it on lm-sensors.org/wiki. -- Jean Delvare _______________________________________________ lm-sensors mailing list lm-sensors@lm-sensors.org http://lists.lm-sensors.org/mailman/listinfo/lm-sensors