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Sat, 17 Jan 2026 00:27:03 -0800 Date: Sat, 17 Jan 2026 10:27:01 +0200 From: Zhi Wang To: Danilo Krummrich CC: Gary Guo , Alice Ryhl , , , , , , , , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v9 2/5] rust: io: factor common I/O helpers into Io trait Message-ID: <20260117102701.3aecf2ce@inno-notebook> In-Reply-To: References: <20260115212657.399231-1-zhiw@nvidia.com> <20260115212657.399231-3-zhiw@nvidia.com> X-Mailer: Claws Mail 4.2.0 (GTK 3.24.41; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-NV-OnPremToCloud: ExternallySecured X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PEPF000066EB:EE_|BL1PR12MB5969:EE_ X-MS-Office365-Filtering-Correlation-Id: 196e3e5f-cad6-4784-3639-08de55a23d5c X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|82310400026|376014|7416014|36860700013|7053199007; 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X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 Jan 2026 08:27:23.4697 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 196e3e5f-cad6-4784-3639-08de55a23d5c X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.160];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: CO1PEPF000066EB.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5969 On Fri, 16 Jan 2026 16:27:27 +0100 "Danilo Krummrich" wrote: > (Cc: Markus) > > On Fri Jan 16, 2026 at 4:23 PM CET, Gary Guo wrote: > > I wonder if we can keep all methods on `Io` trait. And then have > > marker trait to represent capability on performing Io access. > > > > Something like: > > > > trait IoCapable {} > > > > trait Io { > > fn read8(&self, offset: usize) -> u8 where Self: IoCapable; > > fn read16(&self, offset: usize) -> u16 where Self: > > IoCapable; fn read32(&self, offset: usize) -> u32 where Self: > > IoCapable; fn read64(&self, offset: usize) -> u64 where Self: > > IoCapable; } > > > > Then you have a single (non-marker) trait and not a hierachy of > > them. > > I think that is a great idea. I think it will also help with > supporting I/O backends based on regmap. Agreed. The IoCapable marker trait approach is much cleaner and solves the hierarchy complexity Alice pointed out. I'll pick this up for v10. Thanks! Z.