Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932158Ab3CMKyH (ORCPT ); Wed, 13 Mar 2013 06:54:07 -0400 Received: from mga09.intel.com ([134.134.136.24]:32753 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754027Ab3CMKyF (ORCPT ); Wed, 13 Mar 2013 06:54:05 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,834,1355126400"; d="scan'208";a="300864097" Message-ID: <1363172096.11441.11.camel@sauron.fi.intel.com> Subject: Re: [PATCH V4 1/3] mtd: add new fields to nand_flash_dev{} From: Artem Bityutskiy Reply-To: artem.bityutskiy@linux.intel.com To: Huang Shijie Cc: dwmw2@infradead.org, computersforpeace@gmail.com, linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org Date: Wed, 13 Mar 2013 12:54:56 +0200 In-Reply-To: <1362653364-29993-2-git-send-email-b32955@freescale.com> References: <1362653364-29993-1-git-send-email-b32955@freescale.com> <1362653364-29993-2-git-send-email-b32955@freescale.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.6.3 (3.6.3-2.fc18) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1296 Lines: 37 On Thu, 2013-03-07 at 18:49 +0800, Huang Shijie wrote: > diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h > index 591eeeb..f0a9d93 100644 > --- a/include/linux/mtd/nand.h > +++ b/include/linux/mtd/nand.h > @@ -578,6 +578,8 @@ struct nand_chip { > * @erasesize: eraseblock size in bytes (determined from the extended ID if 0) > * @chipsize: total chip size in MiB > * @options: stores various chip bit options > + * @id_len: The valid length of the @id. > + * @oobsize: OOB size > */ > struct nand_flash_dev { > char *name; > @@ -592,6 +594,8 @@ struct nand_flash_dev { > unsigned long chipsize; > unsigned long erasesize; > unsigned long options; > + unsigned long id_len; > + unsigned long oobsize; > }; Why are these of type 'long', which is 64 bits in 64-bit architectures, which seems to be unnecessarily big. Wouldn't 'unsigned int' be enough? Also, can we avoid having the 'id_len' field? Can the end of the sequence of ID's be marked with a '0' or '0xFF' marker instead? -- Best Regards, Artem Bityutskiy -- 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/