From patchwork Tue Dec 10 22:46:40 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Danilo Krummrich X-Patchwork-Id: 13902406 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F29571EE7BD; Tue, 10 Dec 2024 22:51:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733871082; cv=none; b=XRApYnUwEKHiLKhbMUi2eJJ+QVp4ixrCpKrarFlt9I+Q14Obk1ztrxj2EjnKTp3DJhIovhPBSoIO3fiM6ewcZg0IhJviOmShQKm/7TXeraGRVYLvy1f7RWK6/B+pkvrrKX5WgtXL3xSGuVNgpwV3Lu045Rb7q1juLA6vdkqyftw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733871082; c=relaxed/simple; bh=G82NOJZHyH6ULzotBAiLVDncCdayd7kGRmb8TyDikAg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MOlNiS4jw9Zsnd3J0QR/M+1BdjPXflgdrkHu1U1LPQpy8MPZNtLwNa86drPbV4n7/hdU3KrT2k+gWmV43QtNMlg9RCT5yY41b0vj1KeBjNqZ8yc0vlReEVJlaLMTbEeflM1G6BuQeO2/5cKuKHg6DJxpIck7So9aO+Xx0Hd4L6M= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=V8pa0ypY; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="V8pa0ypY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C949CC4CEE0; Tue, 10 Dec 2024 22:51:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1733871081; bh=G82NOJZHyH6ULzotBAiLVDncCdayd7kGRmb8TyDikAg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=V8pa0ypYAZiYq0hdyoSrIBQvMVo0ftI6v/8AWlaJjM4UxHUxMJBfc97Zdr1kYnnQx nHmyLRT5lYxPAdoc8JUZDWEfOmDetvYYGrhiA0NB5r8Ihtb8vnkfkpItd/AP3uzagA 0vZVh2A1BhL/iXm+rSD4JO3El9ftZrYx461xuXXeaEIrvuzv2Tj791uU1/qJQ6a/sI vWvFIVcNcxFhUyjllskwcrrKG1kjtu2I/fO03zQHY1HsQR7/7jZKwuyXr9l9Fy9tgB ZuBGkFgSiMtVSkHqR69a3LCNehhClCbWp7/BQoUo2CHS/OZyV6lvc80md6pU0Iihjk iwRs7Lt1NhnnQ== From: Danilo Krummrich To: gregkh@linuxfoundation.org, rafael@kernel.org, bhelgaas@google.com, ojeda@kernel.org, alex.gaynor@gmail.com, boqun.feng@gmail.com, gary@garyguo.net, bjorn3_gh@protonmail.com, benno.lossin@proton.me, tmgross@umich.edu, a.hindborg@samsung.com, aliceryhl@google.com, airlied@gmail.com, fujita.tomonori@gmail.com, lina@asahilina.net, pstanner@redhat.com, ajanulgu@redhat.com, lyude@redhat.com, robh@kernel.org, daniel.almeida@collabora.com, saravanak@google.com, dirk.behme@de.bosch.com, j@jannau.net, fabien.parent@linaro.org, chrisi.schrefl@gmail.com Cc: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, devicetree@vger.kernel.org, Danilo Krummrich Subject: [PATCH v5 13/16] rust: driver: implement `Adapter` Date: Tue, 10 Dec 2024 23:46:40 +0100 Message-ID: <20241210224947.23804-14-dakr@kernel.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241210224947.23804-1-dakr@kernel.org> References: <20241210224947.23804-1-dakr@kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In order to not duplicate code in bus specific implementations (e.g. platform), implement a generic `driver::Adapter` to represent the connection of matched drivers and devices. Bus specific `Adapter` implementations can simply implement this trait to inherit generic functionality, such as matching OF or ACPI device IDs and ID table entries. Suggested-by: Rob Herring (Arm) Signed-off-by: Danilo Krummrich --- rust/kernel/driver.rs | 59 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 58 insertions(+), 1 deletion(-) diff --git a/rust/kernel/driver.rs b/rust/kernel/driver.rs index ab0bb46fe2cc..d169899a5da1 100644 --- a/rust/kernel/driver.rs +++ b/rust/kernel/driver.rs @@ -6,7 +6,9 @@ //! register using the [`Registration`] class. use crate::error::{Error, Result}; -use crate::{init::PinInit, str::CStr, try_pin_init, types::Opaque, ThisModule}; +use crate::{ + device, device_id, init::PinInit, of, str::CStr, try_pin_init, types::Opaque, ThisModule, +}; use core::pin::Pin; use macros::{pin_data, pinned_drop}; @@ -114,3 +116,58 @@ macro_rules! module_driver { } } } + +/// The bus independent adapter to match a drivers and a devices. +/// +/// This trait should be implemented by the bus specific adapter, which represents the connection +/// of a device and a driver. +/// +/// It provides bus independent functions for device / driver interactions. +pub trait Adapter { + /// The type holding driver private data about each device id supported by the driver. + type IdInfo: 'static; + + /// The [`of::IdTable`] of the corresponding driver. + fn of_id_table() -> of::IdTable; + + /// Returns the driver's private data from the matching entry in the [`of::IdTable`], if any. + /// + /// If this returns `None`, it means there is no match with an entry in the [`of::IdTable`]. + #[cfg(CONFIG_OF)] + fn of_id_info(dev: &device::Device) -> Option<&'static Self::IdInfo> { + let table = Self::of_id_table(); + + // SAFETY: + // - `table` has static lifetime, hence it's valid for read, + // - `dev` is guaranteed to be valid while it's alive, and so is `pdev.as_ref().as_raw()`. + let raw_id = unsafe { bindings::of_match_device(table.as_ptr(), dev.as_raw()) }; + + if raw_id.is_null() { + None + } else { + // SAFETY: `DeviceId` is a `#[repr(transparent)` wrapper of `struct of_device_id` and + // does not add additional invariants, so it's safe to transmute. + let id = unsafe { &*raw_id.cast::() }; + + Some(table.info(::index(id))) + } + } + + #[cfg(not(CONFIG_OF))] + fn of_id_info(_dev: &device::Device) -> Option<&'static Self::IdInfo> { + None + } + + /// Returns the driver's private data from the matching entry of any of the ID tables, if any. + /// + /// If this returns `None`, it means that there is no match in any of the ID tables directly + /// associated with a [`device::Device`]. + fn id_info(dev: &device::Device) -> Option<&'static Self::IdInfo> { + let id = Self::of_id_info(dev); + if id.is_some() { + return id; + } + + None + } +}