From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932439Ab0HDKbr (ORCPT ); Wed, 4 Aug 2010 06:31:47 -0400 Received: from n79.bullet.mail.sp1.yahoo.com ([98.136.44.39]:21988 "HELO n79.bullet.mail.sp1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1756983Ab0HDKbq (ORCPT ); Wed, 4 Aug 2010 06:31:46 -0400 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 450026.80024.bm@omp124.mail.gq1.yahoo.com DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=pacbell.net; h=Message-ID:X-YMail-OSG:Received:X-Mailer:Date:From:Subject:To:Cc:In-Reply-To:MIME-Version:Content-Type; b=yk2eYdCYWN0zJgZ54KEVEZlCnaiEp44v9XNR1XICdW+/3RXgU0Y8pBHfpRlBtqq67sFjyq8XWa//MBXaCvehEZ4Ju6aHKUhT17NpxhE7uYOu/gPKNaCkOvFChSb0GV99sgYH8W1skDrLHVypcCvsJB/ytwuU+CepWUlfiQ+Zgwc=; Message-ID: <350720.60481.qm@web180309.mail.gq1.yahoo.com> X-YMail-OSG: 3FQv.nkVM1k1MvkkUdoXeh3Z4WassdhfVD.JpQg_3U.MCmH fuEDmV8LFR.l47LC7zTGsjg90ubKNnFcuZaZo7_WkjjwqzrOPcsg6LKestVa kV2vJiyPp1xycdGITZgPYWP0954NIhmzZ5bi5FbJVaK3IMoOoRvJ_._wcZ4X eyjugtiP_thlDku2oT4pTnbqetOXGs3cCd2cE.An31KYbCkxD8NE6b6fHZqG rBDmvu.p9X6WuEt8C19AmnDIbZHHRUBOrHBzYGKNsKG1QZSCARyUltBNo_4U FrVCBSxmmu4eI6i3Y5zY0y3j4N8FZn6P14HXzVoIeMNACZj1N.T3a5mZRy2a mysjZgFO1Dp.umxWp_QDdCEqddkb_TVOQ X-Mailer: YahooMailClassic/11.3.2 YahooMailWebService/0.8.105.279950 Date: Wed, 4 Aug 2010 03:31:45 -0700 (PDT) From: David Brownell Subject: RE: [PATCH 1/2] mtdpart: memory accessor interface for MTD layer To: David Woodhouse Cc: "'Kevin Hilman'" , Sudhakar Rajashekhara , "'Bernd Schmidt'" , "'Nicolas Pitre'" , linux-kernel@vger.kernel.org, "'David Howells'" , "'David Brownell'" , linux-mtd@lists.infradead.org, "'Andrew Morton'" In-Reply-To: <1280916725.19499.12.camel@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --- On Wed, 8/4/10, David Woodhouse wrote: > On Wed, 2010-07-07 at 04:08 -0700, > David Brownell wrote: > > > > I think the short answer is that the callout is > > what provides the board drivers enough information > > to make the correct calls. EMPHASIS ON "CORRECT" ... > I don't see how. > > The only information it passes to the callout is the > information it was > already *given* in the partition structure. There can be multiple such structures, each of which describes different data to be extracted from different persistent media contexts. Examples: one context holds one MAC address (and another, a different one) ... another might embed calibration data; another, serial numbers; etc. Pass the wrong context around, you've trashed all the data instead of getting it right. > I'm more inclined to believe Sudhakar's claim that you'll > get an > 'initialization sequence problem', although I'm not sure I > believe it > can't be solved in a better way than this. "Initialization sequence" is a grab-bag category that covers most init issues. Point is to ensure that enough of the right context information is available to initialize correctly. So the right data is extracted and passed on. > > I'm also unhappy that it only works on partitioned devices > -- that seems wrong. Very different issue. Seems easily fixable if needed. Agreed that e.g. EEPROMS won't often be partitioned (unlike flash).