From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758165AbcHYIrU (ORCPT ); Thu, 25 Aug 2016 04:47:20 -0400 Received: from mail-oi0-f67.google.com ([209.85.218.67]:35776 "EHLO mail-oi0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753631AbcHYIrR (ORCPT ); Thu, 25 Aug 2016 04:47:17 -0400 MIME-Version: 1.0 In-Reply-To: References: <20160823220404.9887-1-zajec5@gmail.com> <20160824175345.7033-1-zajec5@gmail.com> From: =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= Date: Thu, 25 Aug 2016 10:32:29 +0200 Message-ID: Subject: Re: [PATCH RFC V3.5] leds: trigger: Introduce an USB port trigger To: Jacek Anaszewski Cc: Richard Purdie , Felipe Balbi , Greg KH , Peter Chen , "linux-usb@vger.kernel.org" , =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= , Jonathan Corbet , Ezequiel Garcia , Stephan Linz , Matthias Brugger , Boris Brezillon , Geert Uytterhoeven , "open list:DOCUMENTATION" , open list , "open list:LED SUBSYSTEM" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id u7P8lOjg003299 On 25 August 2016 at 10:03, Jacek Anaszewski wrote: > On 08/24/2016 07:52 PM, Rafał Miłecki wrote: >> >> From: Rafał Miłecki >> >> This commit adds a new trigger responsible for turning on LED when USB >> device gets connected to the specified USB port. This can can useful for >> various home routers that have USB port(s) and a proper LED telling user >> a device is connected. >> >> The trigger gets its documentation file but basically it just requires >> specifying USB port in a Linux format (e.g. echo 1-1 > new_port). >> >> During work on this trigger there was a plan to add DT bindings for it, >> but there wasn't an agreement on the format yet. This can be worked on >> later, a sysfs interface is needed anyway for platforms not using DT. >> >> Signed-off-by: Rafał Miłecki >> --- >> V2: Trying to add DT support, idea postponed as it will take more time >> to discuss the bindings. >> V3: Fix typos in commit and Documentation (thanks Jacek!) >> Use "ports" sysfs file for adding and removing USB ports (thx Jacek) >> Check if there is USB device connected after adding new USB port >> Fix memory leak or two >> V3.5: Fix e-mail address (thanks Matthias) >> Simplify conditions in usbport_trig_notify (thx Matthias) >> Make "ports" a subdirectory with file per port, to match one value >> per file sysfs rule (thanks Greg) >> As "ports" couldn't be used for adding and removing ports anymore, >> there are now "new_port" and "remove_port". Having them makes this >> API also common with e.g. pci and usb buses. > > > Now writing new_port with "1-1" produces a file named "1-1" in the > ports directory with 000 permissions. I think that what Greg had > on mind by referring to "one value per file" rule was a set of > files representing ports, like "1-1 1-2 2-1", and each file should be > readable/writeable. On the other hand, when I described my idea with "new_port" and "remove_port", Greg replied with "Maybe", so I'm not sure if he really got a design you described in his mind. Greg: could you comment on this sysfs interface, please? :) -- Rafał