From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752538Ab3EBGSC (ORCPT ); Thu, 2 May 2013 02:18:02 -0400 Received: from devils.ext.ti.com ([198.47.26.153]:36348 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751397Ab3EBGR7 (ORCPT ); Thu, 2 May 2013 02:17:59 -0400 From: "Gupta, Pekon" To: Huang Shijie CC: "computersforpeace@gmail.com" , "linux-mtd@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "dedekind1@gmail.com" , "dwmw2@infradead.org" Subject: RE: [PATCH V4 5/9] mtd: replace the hardcode with the onfi_feature() Thread-Topic: [PATCH V4 5/9] mtd: replace the hardcode with the onfi_feature() Thread-Index: AQHOQmAouYQ3/CJ+jUWG0+OGq/54/JjujdmggAIc74CAALvK8P//g3WAgACHJoA= Date: Thu, 2 May 2013 06:17:27 +0000 Message-ID: <20980858CB6D3A4BAE95CA194937D5E73E9C0A2F@DBDE04.ent.ti.com> References: <1366967337-5534-1-git-send-email-b32955@freescale.com> <1366967337-5534-6-git-send-email-b32955@freescale.com> <20980858CB6D3A4BAE95CA194937D5E73E9BF544@DBDE04.ent.ti.com> <5181CC19.8000904@freescale.com> <20980858CB6D3A4BAE95CA194937D5E73E9C09FC@DBDE04.ent.ti.com> <51820127.5060003@freescale.com> In-Reply-To: <51820127.5060003@freescale.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [172.24.170.142] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id r426I7Fk001881 > 于 2013年05月02日 13:42, Gupta, Pekon 写道: > >>>> - *busw = 0; > >>>> - if (le16_to_cpu(p->features)& 1) > >>>> - *busw = NAND_BUSWIDTH_16; > >>>> + > >>>> + *busw = (onfi_feature(chip)& ONFI_FEATURE_16_BIT_BUS) ? > >>>> + NAND_BUSWIDTH_16 : 0; > >>> Is this really needed ? you have already checked the 'onfi_version' > >> above in > >>> nand_flash_detect_onfi() .. > >>> if (!chip->onfi_version) { > >>> pr_info("%s: unsupported ONFI version: %d\n", > >> __func__, val); > >>> return 0; > >>> } > >>> > >>> > >> I think checking the onfi_version has no relationship with this patch. :) > >> This patch is just replace the hardcode for 16-bit onfi nand check. > >> > > [Pekon]: [Patch 3/9]: add a helper to get the supported features > > I mean, do you really need this helper function ? > > +static inline int onfi_feature(struct nand_chip *chip) > > +{ > > + return chip->onfi_version ? le16_to_cpu(chip- > >onfi_params.features) : 0; > > + } > > > > Following change should have been enough.. > > *busw = (le16_to_cpu(p->features)& ONFI_FEATURE_16_BIT_BUS) ? > > NAND_BUSWIDTH_16 : 0; > yes. for this function, it's enough. > > But we may use the onfi_feature() in other places, such as some drivers. > That's reason why i added this helper. > [Pekon]: onfi_feature() is actually not useful unless someone re-scans the param page again. And once the device is probed following should be used to check if it’s a x16 device. If (chip->options & NAND_BUSWIDTH_16) My view-point was that the code should have less redundancy :-) Anyways, Thanks for your other patch for reading extended_param_page. I too wanted that ecc.codeword and ecc.strength should come from device's parameters. I'll ack them once, I test using my driver. with regards, pekon {.n++%ݶw{.n+{G{ayʇڙ,jfhz_(階ݢj"mG?&~iOzv^m ?I