From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx3.redhat.com (mx3.redhat.com [172.16.48.32]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n0FEgcns015998 for ; Thu, 15 Jan 2009 09:42:38 -0500 Received: from dd18532.kasserver.com (dd18532.kasserver.com [85.13.139.13]) by mx3.redhat.com (8.13.8/8.13.8) with ESMTP id n0FEfCDu020352 for ; Thu, 15 Jan 2009 09:41:13 -0500 Received: from tuvok (p4FCA72CF.dip.t-dialin.net [79.202.114.207]) by dd18532.kasserver.com (Postfix) with ESMTP id E5339181C4A84 for ; Thu, 15 Jan 2009 15:41:15 +0100 (CET) Date: Thu, 15 Jan 2009 15:41:11 +0100 From: Carsten Meier To: video4linux-list@redhat.com Message-ID: <20090115154111.36cc25d1@tuvok> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: How to identify USB-video-devices List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: video4linux-list-bounces@redhat.com Errors-To: video4linux-list-bounces@redhat.com List-ID: Hello list, we recently had a discussion on the pvrusb2-list on how to identify a video-device connected via USB from an userspace app. (Or more precisely on how to associate config-data with a particular device). This led to a patch which returned the device's serial-no. in v4l2_capability's bus_info field. This one has been rejected, but I really feel that this is the right way to go. Here's the thread: http://www.isely.net/pipermail/pvrusb2/2009-January/002091.html I think the meaning of the bus_info-field should be modified slightly for USB-devices to reflect its dynamic nature. At least a string that won't change on dis-/reconnect and standby/wake-up-cycles should be returned. If a device has a unique serial-no. it is a perfect candidate for this, if not, some USB-port-info should be returned that won't change if the device is connected to the same port through the same hub. What do you think? (BTW: I'm not a kernel-hacker, I'm writing this from the perspective of an app-developer) Regards, Carsten -- video4linux-list mailing list Unsubscribe mailto:video4linux-list-request@redhat.com?subject=unsubscribe https://www.redhat.com/mailman/listinfo/video4linux-list