From patchwork Thu Dec 19 17:04:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Danilo Krummrich X-Patchwork-Id: 13915354 X-Patchwork-Delegate: bhelgaas@google.com 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 1C9941B4221; Thu, 19 Dec 2024 17:06:02 +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=1734627963; cv=none; b=KyaYRujGz1I+FA4h+1O9dfoBsti2Qez3OMno/p+GSknF63JIdWEBtiA+XhwwRhEem+Q+fhY1hKeJ/hv8Fssd8EYdDXUaETLz4ZLWPi0ihCq90rEls7XI58Fj+5EabMFGWpEcYLs6srDLWIwXiXgxjZcHpxEvUDwQ8gdH85LTMNA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734627963; c=relaxed/simple; bh=zdeZqUkhnQ1ZXijSEcZxULhSXuBX39UFyXzYg6i8/YQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZOVWDnb5h+osdIDHJrY+RvGpLE+ddRHhCt7fi7IVqZJ4SjGn8J0Wi5p+hyCodAuPaSGc4NScosbwcqFFu7Us3KBkm5/bWXCkltzgUBEUpKghu8x9d+Tu0j4caLZLBAvYApZT97oC8B0EsA3HI2z5e3ZVYSaUMmSgZACoIYQXy5I= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=UfvIoyuF; 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="UfvIoyuF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 65EB5C4CED6; Thu, 19 Dec 2024 17:05:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1734627962; bh=zdeZqUkhnQ1ZXijSEcZxULhSXuBX39UFyXzYg6i8/YQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UfvIoyuFMS89JQPIFfeBRaP21xM4zEhlhyxMLCJN7Z+zPHzh4tZSZTK5JtwTVaDPJ Hyfx6RgHMCCgxYSuwL0Hb9g7Ahe9MQuItl3lj8hZ6r3fE8kKxRZ5uqB0xjIBByXJRi NFNrguO0Ku71c79MvrcReObrPpEMADa0fmznR+QhxNw9xyhHypj5nzP/N1CZqIMkyp dr6g/OiZ2aj3m2Z+yVr8+SswgRcYAF91+Dvpv2VpF+qz7M2gLT5fF9J8ao7IkPtT5k 7GOjwZMaUPFNHOO+agTUEXPB7xZHxp6fWeCwqI2lYFwSUev15vyZHsV3KDZyoOVDWX avRO8kRH+n/bg== 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, paulmck@kernel.org Cc: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, devicetree@vger.kernel.org, rcu@vger.kernel.org, Danilo Krummrich Subject: [PATCH v7 13/16] rust: driver: implement `Adapter` Date: Thu, 19 Dec 2024 18:04:15 +0100 Message-ID: <20241219170425.12036-14-dakr@kernel.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20241219170425.12036-1-dakr@kernel.org> References: <20241219170425.12036-1-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/bindings/bindings_helper.h | 1 + rust/kernel/driver.rs | 58 ++++++++++++++++++++++++++++++++- 2 files changed, 58 insertions(+), 1 deletion(-) diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h index 6d7a68e2ecb7..8fe70183a392 100644 --- a/rust/bindings/bindings_helper.h +++ b/rust/bindings/bindings_helper.h @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include diff --git a/rust/kernel/driver.rs b/rust/kernel/driver.rs index c1957ee7bb7e..c630e65098ed 100644 --- a/rust/kernel/driver.rs +++ b/rust/kernel/driver.rs @@ -6,7 +6,7 @@ //! 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, init::PinInit, of, str::CStr, try_pin_init, types::Opaque, ThisModule}; use core::pin::Pin; use macros::{pin_data, pinned_drop}; @@ -115,3 +115,59 @@ fn init( } } } + +/// 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() -> Option>; + + /// 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))] + #[allow(missing_docs)] + 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 + } +}