From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oliver Hartkopp Subject: Re: [RFC PATCH] can: add tx/rx led trigger support Date: Thu, 12 Apr 2012 08:05:33 +0200 Message-ID: <4F8670AD.1050104@hartkopp.net> References: <1334093965-2692-1-git-send-email-fabio.baltieri@gmail.com> <4F852161.90706@hartkopp.net> <4F85D553.2010303@hartkopp.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mo-p00-ob.rzone.de ([81.169.146.161]:26021 "EHLO mo-p00-ob.rzone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750884Ab2DLGFa (ORCPT ); Thu, 12 Apr 2012 02:05:30 -0400 In-Reply-To: Sender: linux-can-owner@vger.kernel.org List-ID: To: Fabio Baltieri Cc: linux-can@vger.kernel.org On 11.04.2012 21:36, Fabio Baltieri wrote: > On Wed, Apr 11, 2012 at 9:02 PM, Oliver Hartkopp wrote: > I should add a check to skip it entirely if led_off_delay == 0 as a > run-time "optimization" if the feature is not used (triggers does not > provide a use-counter). Yes. That's a good idea. > Do you think it should be disabled by default? The LED triggers? Yes. They should be disabled by default. So far i assume there's a very limited number of hardware having extra LEDs. > >> The second question: >> >> Is the LED "blinking" on traffic or is it just "on" for some time when a CAN >> frame is processed? > > It stays on for some time after each frame. Above a certain > packet-rate (1/led_off_delay) LED appear to be constantly on. You can > tell periodic packets from bursts from it but nothing more. Ok. That's fine. > Quick not-so-off-topic - I have a small userspace deamon on my router > which blinks an LED every 100kB of traffic on the WAN interface, which > is nice because you can almost tell the network load just by looking > at it! Much more useful than the standard activity LED. (sometimes I > think I'm taking this too seriously...) Don't know if traffic counting is a good idea for the first step. If we all find a really needed use-case we might think about it later. Regards, Oliver