From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757626AbcEDIOx (ORCPT ); Wed, 4 May 2016 04:14:53 -0400 Received: from mailout3.w1.samsung.com ([210.118.77.13]:45940 "EHLO mailout3.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752421AbcEDIOu (ORCPT ); Wed, 4 May 2016 04:14:50 -0400 Date: Wed, 04 May 2016 10:14:46 +0200 From: Krzysztof Opasiak Subject: Re: [PATCH 1/2] usb: configfs: allow UDC binding rule configured as binding to *any* UDC In-reply-to: <1462244665-27681-2-git-send-email-changbin.du@intel.com> To: changbin.du@intel.com, balbi@kernel.org Cc: gregkh@linuxfoundation.org, corbet@lwn.net, linux-usb@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, "Du, Changbin" , Du@vger.kernel.org Message-id: <5729AF76.7080508@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=windows-1252 Content-transfer-encoding: 7bit X-AuditID: cbfec7f5-f792a6d000001302-0a-5729af774caf X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrJLMWRmVeSWpSXmKPExsVy+t/xq7rl6zXDDd7Pk7c41vaE3eLJtXNM FhsvHmeyeHKgndFixYqdjBbNi9ezWSxsW8JicXnXHDaLRctamR04PXbOusvusXjPSyaPTas6 2Tz2z10D5PZNZvX4vEkugC2KyyYlNSezLLVI3y6BK+Pdpy0sBVfYK351PGNqYPzB2sXIySEh YCLRffMcG4QtJnHh3nogm4tDSGApo0Tfr7lMEM5zRonpq2Yxg1QJCyRLTF/fyg5iiwhoS/Te aGSEKGoEKpoAkWAWOMQoMfsw0AoODjYBfYl5u0RBwrwCWhJPtmxiAbFZBFQlrr14xghiiwpE SDyZe5IRokZQ4sfke2A1nAJuEp9WHGUGGcMsoCdx/6IWxHR5ic1r3jJPYBSYhaRjFkLVLCRV CxiZVzGKppYmFxQnpeca6RUn5haX5qXrJefnbmKERMDXHYxLj1kdYhTgYFTi4X3hrRkuxJpY VlyZC/QFB7OSCK/ICqAQb0piZVVqUX58UWlOavEhRmkOFiVx3pm73ocICaQnlqRmp6YWpBbB ZJk4OKUaGK8W/NR1rCqrdXxlWG0fdnCbdMyeaMVtdvrGK2Kt5Ms+8B+7umbdu9z155dq+jVK le06rbGQY0X7FFXzhKL2x57bPnlPfbLvofne/H2v3qrG5N0Q3TjDQ+Ndu/qTaSF5IT9LejPW PHj4xn7Blfcab9cfsHbemurbMr3zgfHO8zqFzQ1PFznc4VViKc5INNRiLipOBAAgrwsQfAIA AA== References: <1462244665-27681-1-git-send-email-changbin.du@intel.com> <1462244665-27681-2-git-send-email-changbin.du@intel.com> User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/03/2016 05:04 AM, changbin.du@intel.com wrote: > From: "Du, Changbin" > > On most platforms, there is only one device controller available. > In this case, we desn't care the UDC's name. So let's ignore the > name by setting 'UDC' to 'any'. Hmm libubsgx allows to do this for a very long time. You simply pass NULL instead of pointer to usbg_udc. It is also possible to do this from command line, just simply: $ echo `ls -1 /sys/class/udc | head -n 1` > UDC So if we can easily do this from user space what's the benefit of adding this special "any" keyword to kernel? > And also we can change UDC name > at any time if it is not binded (no need set to "" first). > Not sure if: $ echo "" > UDC is really a problem. Personally I'm quite used to situation in which I have to turn the light off before turning it on once again;) Cheers, -- Krzysztof Opasiak Samsung R&D Institute Poland Samsung Electronics