From mboxrd@z Thu Jan 1 00:00:00 1970 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 01BB12F3E; Sun, 8 Jun 2025 10:48:40 +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=1749379721; cv=none; b=sAciZloOT/8JQAPsgWTSPFeOwb0zKbxRyr2RFu2ifYjWAEPw6lpA5gWBS1uxpIZZUGmEqjtSj/vsRfk/JezFmHVfn9dBs8+OM+DBJEZU2IKfV5JtFJh/ifKeaOYJ6zwkUyT/SSnAOFZ1fi/s83WUtNujPSjRIo9fExim6+Zv1ao= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749379721; c=relaxed/simple; bh=AnI/cidWMnRFA5NIz5etjUog1SNqGjwokm1tz/aotaQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=X1X+G4bYNZllayjs8USFIi07YBoQlPF8QX1omYHP7xNK8psDjIgKKnDmCXN6NSDkA+GIN2mU0cKLpWAP9nvv9SqKHmzG0g1tcSYy2rlwHpFgtZDyjgEi3ZHiA87WdfUTw3alY5c+/odiLnRL+fCQUs6CrbAtWvV/+OSFgK//Vzk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=c+FzWM05; 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="c+FzWM05" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 708B4C4CEEE; Sun, 8 Jun 2025 10:48:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1749379720; bh=AnI/cidWMnRFA5NIz5etjUog1SNqGjwokm1tz/aotaQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=c+FzWM05XYK4BIU51gGGGgEJAWMslEGiEpppSHl69eCMoo0WO2Zr1Rw+nMb88GQyY bag2Cx7wtbzfNraPq9K4PF4C7x4L4Rr0nS/BgJhRzPizjdEx5RxT5OVeLXPEiU6uk3 TmVNVVDVOVHVsaIDmR2BCiPvO1fjdsW1BOK2SCqAmg6JUwKqWrG36SUk+dumsG5NZh ExLjsrUGpNxdjb9+CYx8Pt/9DKGG0fRn3R843CV0B1ZNpF2UzkF7/yWtsjq6diPw6y olNrkOjfYCue1r/p5gq7vxrJkHpOohpnsRPtaFiQpe8KGPUjwLPsoeKG4HcQ4oeOU0 uA/JY0ol5VMZg== Date: Sun, 8 Jun 2025 12:48:33 +0200 From: Danilo Krummrich To: Benno Lossin Cc: Igor Korotin , ojeda@kernel.org, alex.gaynor@gmail.com, rafael@kernel.org, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-acpi@vger.kernel.org, boqun.feng@gmail.com, gary@garyguo.net, bjorn3_gh@protonmail.com, benno.lossin@proton.me, a.hindborg@kernel.org, aliceryhl@google.com, tmgross@umich.edu, lenb@kernel.org, wedsonaf@gmail.com, viresh.kumar@linaro.org, alex.hung@amd.com, dingxiangfei2009@gmail.com, Igor Korotin Subject: Re: [PATCH v3 2/4] rust: driver: Add ACPI id table support to Adapter trait Message-ID: References: <20250606170341.3880941-1-igor.korotin.linux@gmail.com> <20250606170817.3881748-1-igor.korotin.linux@gmail.com> Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Sun, Jun 08, 2025 at 09:54:30AM +0200, Benno Lossin wrote: > On Fri Jun 6, 2025 at 7:08 PM CEST, Igor Korotin wrote: > > @@ -141,6 +141,38 @@ pub trait Adapter { > > /// The type holding driver private data about each device id supported by the driver. > > type IdInfo: 'static; > > > > + /// The [`acpi::IdTable`] of the corresponding driver > > + fn acpi_id_table() -> Option>; > > + > > + /// Returns the driver's private data from the matching entry in the [`acpi::IdTable`], if any. > > + /// > > + /// If this returns `None`, it means there is no match with an entry in the [`acpi::IdTable`]. > > + #[cfg(CONFIG_ACPI)] > > + fn acpi_id_info(dev: &device::Device) -> Option<&'static Self::IdInfo> { > > + let table = Self::acpi_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::acpi_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_ACPI))] > > + #[allow(missing_docs)] > > I think we should change this to one single definition and do > > if cfg!(not(CONFIG_ACPI)) { > return None; > } > /* body from above */ > > In a single function instead. Generally, that's fine, but in this case I'd rather keep it as it is for consistency with the rest of the file. > > + fn acpi_id_info(_dev: &device::Device) -> Option<&'static Self::IdInfo> { > > + None > > + } > > + > > /// The [`of::IdTable`] of the corresponding driver. > > fn of_id_table() -> Option>; > > > > @@ -178,6 +210,11 @@ fn of_id_info(_dev: &device::Device) -> Option<&'static Self::IdInfo> { > > /// 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::acpi_id_info(dev); > > + if id.is_some() { > > + return id; > > + } > > Is a driver only going to have one id_info? Or is there some kind of > precedence? A driver potentially has lots of them, but the device is only matching a single entry in one of the driver's ID tables and hence a single ID info.