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dkim=none (message not signed) header.d=none;kernel.org; dmarc=none action=none header.from=nxp.com; x-originating-ip: [183.192.235.111] x-ms-publictraffictype: Email x-ms-office365-filtering-ht: Tenant x-ms-office365-filtering-correlation-id: 959003b8-59ff-4c32-64a0-08d8113bde29 x-ms-traffictypediagnostic: VE1PR04MB6525: x-ms-exchange-transport-forked: True x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:8882; x-forefront-prvs: 04359FAD81 x-ms-exchange-senderadcheck: 1 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: m6KHG73sDXZAyWX49AlNpiK8HZSyGhBQDqrcCuQDMSiIzhE+0k/qgZ/OdPH+9m+Izv8MkfXQc4QAn5t55XPvWknFlKTrfEZmfIYr8FnboCZK0Dz/A7WzgyFlf2ldx80sY6eZLkZEdxdqgvFquoWPXUBini176OshB/906MuEEdiz55CJaz4SkSS5qyc7jjHgSvGsr55fS4GufguCJO4MnRXlEcPRpnyAGDb8yy7eUB/d1I5Nzk7/+1Pa84UVn6IGi7MWH6iZGWvMezAihEQxaiU1EzPRredkNZBE2viZyw/KZGm0PAp0igIa4Lahyb4N5VQtv1QGXJxPpmeKK9sWhg== x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:VE1PR04MB6638.eurprd04.prod.outlook.com;PTR:;CAT:NONE;SFTY:;SFS:(4636009)(396003)(376002)(346002)(39860400002)(366004)(136003)(71200400001)(52536014)(6916009)(8676002)(4326008)(86362001)(33656002)(26005)(4744005)(83380400001)(5660300002)(2906002)(54906003)(8936002)(478600001)(316002)(7416002)(66946007)(66476007)(66556008)(64756008)(66446008)(9686003)(6506007)(55016002)(7696005)(53546011)(186003)(76116006);DIR:OUT;SFP:1101; x-ms-exchange-antispam-messagedata: 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 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 959003b8-59ff-4c32-64a0-08d8113bde29 X-MS-Exchange-CrossTenant-originalarrivaltime: 15 Jun 2020 14:53:29.8763 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: nbwsj8K9HOO5+HieE1raLiD/el0lQkCB81b2qhB5ncpYHZzYNdhAk15xoqFenontzxrESE/DlRdeq06D3IAXUw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VE1PR04MB6525 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020/06/15 22:36 Mark Brown wrote:=20 > On Mon, Jun 15, 2020 at 02:18:54PM +0000, Robin Gong wrote: > > Seems not easy to find a suitable error value, how about EBADR which > > sounds like no any available dma_async_tx_descriptor got by calling > dmaengine_prep_slave_sg? >=20 > > #define EBADR 53 /* Invalid request descriptor */ >=20 > We could also pass in a flag that could be set separately to the error co= de to > indicate that nothing had happened to the hardware yet. Do you mean spi-imx.c checking 'ctlr->flags' before return such error code? Or just like below done in spi.c. +fallback_pio: ret =3D ctlr->transfer_one(ctlr, msg->spi, xfer); if (ret < 0) { + if (ret =3D=3D - EBADR && ctlr->cur_msg_map= ped && + (ctlr->flags & SPI_CONTROLLER_FALLBACK))= { + __spi_unmap_msg(ctlr, msg); + ctlr->fallback =3D true; + goto fallback_pio; + } + From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 54A05C433E0 for ; Mon, 15 Jun 2020 14:53:41 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 291BE206D7 for ; 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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2020/06/15 22:36 Mark Brown wrote: > On Mon, Jun 15, 2020 at 02:18:54PM +0000, Robin Gong wrote: > > Seems not easy to find a suitable error value, how about EBADR which > > sounds like no any available dma_async_tx_descriptor got by calling > dmaengine_prep_slave_sg? > > > #define EBADR 53 /* Invalid request descriptor */ > > We could also pass in a flag that could be set separately to the error code to > indicate that nothing had happened to the hardware yet. Do you mean spi-imx.c checking 'ctlr->flags' before return such error code? Or just like below done in spi.c. +fallback_pio: ret = ctlr->transfer_one(ctlr, msg->spi, xfer); if (ret < 0) { + if (ret == - EBADR && ctlr->cur_msg_mapped && + (ctlr->flags & SPI_CONTROLLER_FALLBACK)) { + __spi_unmap_msg(ctlr, msg); + ctlr->fallback = true; + goto fallback_pio; + } + _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel