Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754417Ab0BVVxT (ORCPT ); Mon, 22 Feb 2010 16:53:19 -0500 Received: from www.tglx.de ([62.245.132.106]:43296 "EHLO www.tglx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753506Ab0BVVxR (ORCPT ); Mon, 22 Feb 2010 16:53:17 -0500 Date: Mon, 22 Feb 2010 22:53:04 +0100 (CET) From: Thomas Gleixner To: Maxim Levitsky cc: David Woodhouse , linux-mtd , linux-kernel , Alex Dubov , joern , stanley.miao@windriver.com, Vitaly Wool Subject: Re: [PATCH 13/15] MTD: add few workarounds to nand system for SmartMedia/xD chips. In-Reply-To: <1266874402.4971.9.camel@maxim-laptop> Message-ID: References: <1266863982-5258-1-git-send-email-maximlevitsky@gmail.com> <1266863982-5258-14-git-send-email-maximlevitsky@gmail.com> <1266874402.4971.9.camel@maxim-laptop> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) 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 Content-Length: 2083 Lines: 58 On Mon, 22 Feb 2010, Maxim Levitsky wrote: > On Mon, 2010-02-22 at 22:25 +0100, Thomas Gleixner wrote: > > On Mon, 22 Feb 2010, Maxim Levitsky wrote: > > > > > * Add an option NAND_SMARTMEDIA that can be set by nand driver > > > If set, it will cause separate ID table to be used, which includes > > > mask rom devices and new xD cards > > > > Why that option ? We can just extend the existing ids table and be > > done. No extra magic needed. > > > > Two reasons. > > First of all several xD chips (I belive the Type M) have exactly same > IDs like normal nand chips. However they don't report capabilities about > pagesize, blocksize, etc. You mean that crap ? + /* xD only */ + {"xD 512MiB 3,3V", 0xDC, 512, 512, 0x4000, XD_TYPEM}, + {"xD 1GiB 3,3V", 0xD3, 512, 1024, 0x4000, XD_TYPEM}, + {"xD 2GiB 3,3V", 0xD5, 512, 2048, 0x4000, XD_TYPEM}, Oh well, that's a perfect example of designed by comittee shit. They abuse the 2k chips IDs and define crappy sizes just to fit the stupid spec. > I am confident that these cards have an internal FTL and controller, and > just 'emulate' that nand interface. Either that or the adapter translates the 512B commands to 2K commands. I bet on the latter. AFAIK are xD cards just as stupid as SmartMedia ones, i.e. bare NAND chips in a flat plastic housing with gold contacts. > Also, my card reports write protect, although, xD cards don't have any > 'switch' to make them protected. Neither have SmartMedia Cards nor bare NAND chips. WP is a pin on the interface which is controlled by the adapter hardware. > Even if there were readonly ROM xD cards (the odds of this are virtually > zero), these won't just expose this in WP bit. Hmm, I wonder whether that horror has the WP bit inverted. Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/