From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759301AbYELIRQ (ORCPT ); Mon, 12 May 2008 04:17:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756182AbYELIQ7 (ORCPT ); Mon, 12 May 2008 04:16:59 -0400 Received: from smtp117.sbc.mail.sp1.yahoo.com ([69.147.64.90]:44333 "HELO smtp117.sbc.mail.sp1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754906AbYELIQ6 (ORCPT ); Mon, 12 May 2008 04:16:58 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=pacbell.net; h=Received:X-YMail-OSG:X-Yahoo-Newman-Property:From:To:Subject:Date:User-Agent:Cc:References:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-Disposition:Message-Id; b=ZgIDIfyefKJb5bWAj/DWBAx0mvT/GAZMBDe+aED76Vz/DY6RjyviTn18ofO1vkenU3JWRhwpL+GJ7yfTdoI7uNCHTimNRt9S9f7VTUpIPl6HMtAMiyPnLpHsdA++gul93h6hb/OGac/TqQjvZpswDv915yMcs00liXpCdZwK+3o= ; X-YMail-OSG: MpOPLOYVM1mzPskfWfceP.SGX6NXE2C6hp8473V5uf2qziq.bUqOBIHtso5Oz3n8rc4kuF6ALr1DiuSUKecYTnZGdakGt4Y9BjjMkzTjYU4Tq_gqLpsHXmoRYn5K8pSZWcY- X-Yahoo-Newman-Property: ymail-3 From: David Brownell To: Marcin Slusarz Subject: Re: drivers/usb/misc/usbtest.c weirdness Date: Mon, 12 May 2008 01:02:22 -0700 User-Agent: KMail/1.9.6 Cc: LKML , Greg Kroah-Hartman , linux-usb@vger.kernel.org References: <20080511202222.GP19058@joi> In-Reply-To: <20080511202222.GP19058@joi> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200805120102.23320.david-b@pacbell.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sunday 11 May 2008, Marcin Slusarz wrote: > > test_ctrl_queue expects (?) positive and negative errnos. > what is going on here? The sign is just a way to flag something: /* some faults are allowed, not required */ The negative ones are required. Positive codes are optional, in the sense that, depending on how the peripheral happens to be implemented, they won't necessarily be triggered. For example, the test to fetch a device qualifier desriptor must succeed if the device is running at high speed. So that test is marked as negative. But when it's full speed, it could legitimately fail; marked as positive. And so on for other tests. Look at how the codes are *interpreted* to see it work.