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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: 78c1ec6c-a227-4087-3571-08d8113708f7 x-ms-traffictypediagnostic: VE1PR04MB6415: x-ms-exchange-transport-forked: True x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:7219; x-forefront-prvs: 04359FAD81 x-ms-exchange-senderadcheck: 1 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: nvTow8U+q7wxBWkMifneUgsotU9ai3gzHeTDsflteZC343sFITeQdbYOa2XWOoHmBLyWghbaSlg1ZfFImikO+9EYkvxz6Wh3e2hJFzsxwe1GAHSh1l4Rf3xPRjj0DTXbq+duH6RvGZaG6mBaHDLURJIGj8aL1dWioSyiiXYKp9Sy9srj30oY5wORjEeFFRlv9Z0B8BbP/2Lhiz2Dkjj78PlaO5IAia6EeW6FzoQgCYTK9OmoCGoLuH/kZjhtagBDxXh38vbfOO4wpRLZJQez8vndOWXdiPblw3vuipvPQgwPSrQUI555KLr9NRH+6+/i 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)(136003)(39860400002)(396003)(366004)(346002)(376002)(54906003)(83380400001)(71200400001)(8936002)(5660300002)(52536014)(186003)(8676002)(26005)(4744005)(316002)(7696005)(478600001)(53546011)(76116006)(66476007)(66556008)(6916009)(64756008)(66446008)(33656002)(6506007)(66946007)(2906002)(86362001)(7416002)(9686003)(4326008)(55016002);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: 78c1ec6c-a227-4087-3571-08d8113708f7 X-MS-Exchange-CrossTenant-originalarrivaltime: 15 Jun 2020 14:18:54.3138 (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: uAzgrywaEFfmYboIEKPk3AJosen31bKXzQtNY3lKjuGd9bZ3EBDNWuJhyv90SyhxLKE9l1c47ALPK0OqBmK67w== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VE1PR04MB6415 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020/06/15 21:39 Mark Brown wrote: > On Mon, Jun 15, 2020 at 01:35:01PM +0000, Robin Gong wrote: > > Then how about choosing specific error code for such dma not ready > > case where nothing went out on the bus neither? >=20 > Yes, that's what I suggested. 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 dmaengi= ne_prep_slave_sg?=20 #define EBADR 53 /* Invalid request descriptor */