From 0242623384c767b1156b61b67894b4ecf6682b8b Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Thu, 16 Oct 2025 14:55:28 +0200 Subject: rust: driver: let probe() return impl PinInit The driver model defines the lifetime of the private data stored in (and owned by) a bus device to be valid from when the driver is bound to a device (i.e. from successful probe()) until the driver is unbound from the device. This is already taken care of by the Rust implementation of the driver model. However, we still ask drivers to return a Result>> from probe(). Unlike in C, where we do not have the concept of initializers, but rather deal with uninitialized memory, drivers can just return an impl PinInit instead. This contributes to more clarity to the fact that a driver returns it's device private data in probe() and the Rust driver model owns the data, manages the lifetime and - considering the lifetime - provides (safe) accessors for the driver. Hence, let probe() functions return an impl PinInit instead of Result>>. Reviewed-by: Alice Ryhl Acked-by: Viresh Kumar Reviewed-by: Alexandre Courbot Acked-by: Greg Kroah-Hartman Signed-off-by: Danilo Krummrich --- rust/kernel/io/mem.rs | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'rust/kernel/io/mem.rs') diff --git a/rust/kernel/io/mem.rs b/rust/kernel/io/mem.rs index 6f99510bfc3a..59096d579644 100644 --- a/rust/kernel/io/mem.rs +++ b/rust/kernel/io/mem.rs @@ -53,7 +53,7 @@ impl<'a> IoRequest<'a> { /// fn probe( /// pdev: &platform::Device, /// info: Option<&Self::IdInfo>, - /// ) -> Result>> { + /// ) -> impl PinInit { /// let offset = 0; // Some offset. /// /// // If the size is known at compile time, use [`Self::iomap_sized`]. @@ -70,7 +70,7 @@ impl<'a> IoRequest<'a> { /// /// io.write32_relaxed(data, offset); /// - /// # Ok(KBox::new(SampleDriver, GFP_KERNEL)?.into()) + /// # Ok(SampleDriver) /// } /// } /// ``` @@ -111,7 +111,7 @@ impl<'a> IoRequest<'a> { /// fn probe( /// pdev: &platform::Device, /// info: Option<&Self::IdInfo>, - /// ) -> Result>> { + /// ) -> impl PinInit { /// let offset = 0; // Some offset. /// /// // Unlike [`Self::iomap_sized`], here the size of the memory region @@ -128,7 +128,7 @@ impl<'a> IoRequest<'a> { /// /// io.try_write32_relaxed(data, offset)?; /// - /// # Ok(KBox::new(SampleDriver, GFP_KERNEL)?.into()) + /// # Ok(SampleDriver) /// } /// } /// ``` -- cgit From 9d39842f6afcd0438c8353a9764d624eef2d160a Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Tue, 4 Nov 2025 14:32:54 +0100 Subject: rust: io: cleanup imports and use "kernel vertical" style Commit 46f045db5a94 ("rust: Add read_poll_timeout_atomic function") initiated the first import change in the I/O module using the agreed "kernel vertical" import style [1]. For consistency throughout the module, adjust all other imports accordingly. While at it, drop unnecessary imports covered by prelude::*. Link: https://docs.kernel.org/rust/coding-guidelines.html#imports [1] Reviewed-by: Zhi Wang Link: https://patch.msgid.link/20251104133301.59402-1-dakr@kernel.org [ Use prelude::* in io/poll.rs. - Danilo ] Signed-off-by: Danilo Krummrich --- rust/kernel/io/mem.rs | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) (limited to 'rust/kernel/io/mem.rs') diff --git a/rust/kernel/io/mem.rs b/rust/kernel/io/mem.rs index 59096d579644..b03b82cd531b 100644 --- a/rust/kernel/io/mem.rs +++ b/rust/kernel/io/mem.rs @@ -4,16 +4,24 @@ use core::ops::Deref; -use crate::c_str; -use crate::device::Bound; -use crate::device::Device; -use crate::devres::Devres; -use crate::io; -use crate::io::resource::Region; -use crate::io::resource::Resource; -use crate::io::Io; -use crate::io::IoRaw; -use crate::prelude::*; +use crate::{ + c_str, + device::{ + Bound, + Device, // + }, + devres::Devres, + io::{ + self, + resource::{ + Region, + Resource, // + }, + Io, + IoRaw, // + }, + prelude::*, +}; /// An IO request for a specific device and resource. pub struct IoRequest<'a> { -- cgit