From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout02.posteo.de (mout02.posteo.de [185.67.36.66]) (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 BD04A305E26 for ; Sat, 15 Nov 2025 17:26:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.67.36.66 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763227570; cv=none; b=hpLVHq/+Mdf5cPV4c+oYT9QpfCsAH/KE96xMs2FDJtavRKjn+JN6Qfq9CoFiKL7I7RHuepQtLtv4kKtI/CpuzOH+gJSfskS8kQ8RdVwHKpQMhpfXKOGM6K4ZaxZ0/mTSlzq8jomyMv5xyeQZ2x45z9ttj2n4qn/KUU+mXbdhewM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763227570; c=relaxed/simple; bh=Uohd819v/S6bIx68JfE/asm+yhU2CxYdcSIDKKM7zLI=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=J2RWtsmf383yOmEu6nMzBGhzP0nmxNUqJOO7d9sxE0xx29syVOcG9JcpOEhE7LivPf7IwUA6FbfMzNZ9bAABV/SFxaUOgJ88jY3lpphdO8wtBh9qRvOsSgnC7yezDmDk5VIdBkqhqPIf7r4/F3F4QayjtANWyrIpWuOAmi7dqmU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=posteo.de; spf=pass smtp.mailfrom=posteo.de; dkim=pass (2048-bit key) header.d=posteo.de header.i=@posteo.de header.b=B+PDPrAq; arc=none smtp.client-ip=185.67.36.66 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=posteo.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=posteo.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=posteo.de header.i=@posteo.de header.b="B+PDPrAq" Received: from submission (posteo.de [185.67.36.169]) by mout02.posteo.de (Postfix) with ESMTPS id 356BB240109 for ; Sat, 15 Nov 2025 18:26:07 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=posteo.de; s=2017; t=1763227567; bh=zqKg1rOa6hGcURHxMPuTQZ+rpn6vivHG4MhrXG7HuXU=; h=From:Date:Subject:MIME-Version:Content-Type: Content-Transfer-Encoding:Message-Id:To:Cc:Autocrypt:OpenPGP:From; b=B+PDPrAqbcnfmqLEN/DD+XLbWiPXCem9loYJoD6Tk0EM4bJTi5gPPBqtKrP6ZQSXi SsLoiM7e7hBXbLHnA+4sPBU6VZEbYqaS/JPXjD8I8ZE30H44zs7HXHhnDYZ3v/4Bvu QsRG6Uda5xGzHzfROFmLRnPuKAeuEG63riYhQC0zBNiprJvrLnhaWMZjR+2eVs42CS vxLxQLFljdDUJZUCKl2cQieHRIsSxJQZGivllXX5l2jE8xpDQeg2lrJ7cSDlon1Bzs u82eD2Xnj3Cj7t1bShQTDSY0l/sj/BekQehL38ToSIm5CAuuv4p78GYlbNIVftkuIN RcCQRf4CsRvBg== Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 4d81BN28Lnz9rxP; Sat, 15 Nov 2025 18:26:04 +0100 (CET) From: Markus Probst Date: Sat, 15 Nov 2025 17:26:06 +0000 Subject: [PATCH v8 4/4] rust: leds: add multicolor classdev abstractions 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="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20251115-rust_leds-v8-4-d9a41f355538@posteo.de> References: <20251115-rust_leds-v8-0-d9a41f355538@posteo.de> In-Reply-To: <20251115-rust_leds-v8-0-d9a41f355538@posteo.de> To: Lee Jones , Pavel Machek , Greg Kroah-Hartman , Dave Ertman , Ira Weiny , Leon Romanovsky , Miguel Ojeda , Alex Gaynor , Boqun Feng , Gary Guo , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross , Danilo Krummrich , "Rafael J. Wysocki" , Bjorn Helgaas , =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= Cc: rust-for-linux@vger.kernel.org, linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Markus Probst X-Developer-Signature: v=1; a=openpgp-sha256; l=9531; i=markus.probst@posteo.de; h=from:subject:message-id; bh=Uohd819v/S6bIx68JfE/asm+yhU2CxYdcSIDKKM7zLI=; b=owEBbQKS/ZANAwAIATR2H/jnrUPSAcsmYgBpGLeiXjdtIOhoUbd0+4XTbYeQmUy/cSXUFP6HL EifxJFwJ1aJAjMEAAEIAB0WIQSCdBjE9KxY53IwxHM0dh/4561D0gUCaRi3ogAKCRA0dh/4561D 0g22D/0Vake9v7h9gKLTz7I+t7b8STaVgeJKrkel5YlOEdbVt44QckXzVbEyKnRaxOYz7Hy2Tk8 Uunl0WR/lQQ6a0lXKH3osHu/zeTM6YZRJ0oTuWmKR/tZyrZG+BYJakZySvpodRTDvmo4vgerXK5 7cSxfHFMwfR1+nZWP/MdNlNJedSjFBJqYJbkgPKLSGtCglVRaMNqj5/XuQv23cRxqwIxy9YdpKT JUJ2iuxlDZjgPTMp44B0ey3tt6OEyqb+0XnFKzGtjo1npOYGFpVdQedRvR6o6mv5ptNOo2uGEqk 3v2yzcgOf2Csj+yUSnzx+7pABS/6oDa7le4+MZDpIxvxkxJJQb4RROPV5xCMNIjFZjlqUNEs5Kn XL8b1cZxQwZwxFbOCMjWfgsDgz/eELR4ip3AoGlX4LaZPRC5lwWYwCgGQKeT4AccoQYFyGzbkJF cD/rrgb1rvtjeYswFj85JfK5xHofLFU38EcIbISWRHTjskFjLHyOdL66CoDscRmZlZg9w6+rAvg EDPfTi9/ZRjm+ifWyiolsy30llgp8xCu4zbi+RWZ1vzZ/tnXqKa++/dgwcbe597nsNa4A0ybT84 Todz0B+gRSzsD7PRF63Q+jqB99JCGXeyTWBwODJ5eKOxUOAXnNnEAm0HvbkLZ+haGb0ZM7j7GHs 3DPgdRhe5/jX0Kw== X-Developer-Key: i=markus.probst@posteo.de; a=openpgp; fpr=827418C4F4AC58E77230C47334761FF8E7AD43D2 Autocrypt: addr=markus.probst@posteo.de; prefer-encrypt=mutual; keydata=xsFNBGiDvXgBEADAXUceKafpl46S35UmDh2wRvvx+UfZbcTjeQOlSwKP7YVJ4JOZrVs93qReNLkO WguIqPBxR9blQ4nyYrqSCV+MMw/3ifyXIm6Pw2YRUDg+WTEOjTixRCoWDgUj1nOsvJ9tVAm76Ww+ /pAnepVRafMID0rqEfD9oGv1YrfpeFJhyE2zUw3SyyNLIKWD6QeLRhKQRbSnsXhGLFBXCqt9k5JA RhgQof9zvztcCVlT5KVvuyfC4H+HzeGmu9201BVyihJwKdcKPq+n/aY5FUVxNTgtI9f8wIbmfAja oT1pjXSp+dszakA98fhONM98pOq723o/1ZGMZukyXFfsDGtA3BB79HoopHKujLGWAGskzClwTjRQ xBqxh/U/lL1pc+0xPWikTNCmtziCOvv0KA0arDOMQlyFvImzX6oGVgE4ksKQYbMZ3Ikw6L1Rv1J+ FvN0aNwOKgL2ztBRYscUGcQvA0Zo1fGCAn/BLEJvQYShWKeKqjyncVGoXFsz2AcuFKe1pwETSsN6 OZncjy32e4ktgs07cWBfx0v62b8md36jau+B6RVnnodaA8++oXl3FRwiEW8XfXWIjy4umIv93tb8 8ekYsfOfWkTSewZYXGoqe4RtK80ulMHb/dh2FZQIFyRdN4HOmB4FYO5sEYFr9YjHLmDkrUgNodJC XCeMe4BO4iaxUQARAQABzRdtYXJrdXMucHJvYnN0QHBvc3Rlby5kZcLBkQQTAQgAOxYhBIJ0GMT0 rFjncjDEczR2H/jnrUPSBQJog714AhsDBQsJCAcCAiICBhUKCQgLAgQWAgMBAh4HAheAAAoJEDR2 H/jnrUPSgdkQAISaTk2D345ehXEkn5z2yUEjaVjHIE7ziqRaOgn/QanCgeTUinIv6L6QXUFvvIfH 1OLPwQ1hfvEg9NnNLyFezWSy6jvoVBTIPqicD/r3FkithnQ1IDkdSjrarPMxJkvuh3l7XZHo49GV HQ8i5zh5w4YISrcEtE99lJisvni2Jqx7we5tey9voQFDyM8jxlSWv3pmoUTCtBkX/eKHJXosgsuS B4TGDCVPOjla/emI5c9MhMG7O4WEEmoSdPbmraPw66YZD6uLyhV4DPHbiDWRzXWnClHSyjB9rky9 lausFxogvu4l9H+KDsXIadNDWdLdu1/enS/wDd9zh5S78rY2jeXaG4mnf4seEKamZ7KQ6FIHrcyP ezdDzssPQcTQcGRMQzCn6wP3tlGk7rsfmyHMlFqdRoNNv+ZER/OkmZFPW655zRfbMi0vtrqK2Awm 9ggobb1oktfd9PPNXMUY+DNVlgR2G7jLnenSoQausLUm0pHoNE8TWFv851Y6SOYnvn488sP1Tki5 F3rKwclawQFHUXTCQw+QSh9ay8xgnNZfH+u9NY7w3gPoeKBOAFcBc2BtzcgekeWS8qgEmm2/oNFV G0ivPQbRx8FjRKbuF7g3YhgNZZ0ac8FneuUtJ2PkSIFTZhaAiC0utvxk0ndmWFiW4acEkMZGrLaM L2zWNjrqwsD2zsFNBGiDvXgBEADCXQy1n7wjRxG12DOVADawjghKcG+5LtEf31WftHKLFbp/HArj BhkT6mj+CCI1ClqY+FYU5CK/s0ScMfLxRGLZ0Ktzawb78vOgBVFT3yB1yWBTewsAXdqNqRooaUNo 8cG/NNJLjhccH/7PO/FWX5qftOVUJ/AIsAhKQJ18Tc8Ik73v427EDxuKb9mTAnYQFA3Ev3hAiVbO 6Rv39amVOfJ8sqwiSUGidj2Fctg2aB5JbeMln0KCUbTD1LhEFepeKypfofAXQbGwaCjAhmkWy/q3 IT1mUrPxOngbxdRoOx1tGUC0HCMUW1sFaJgQPMmDcR0JGPOpgsKnitsSnN7ShcCr1buel7vLnUMD +TAZ5opdoF6HjAvAnBQaijtK6minkrM0seNXnCg0KkV8xhMNa6zCs1rq4GgjNLJue2EmuyHooHA4 7JMoLVHcxVeuNTp6K2+XRx0Pk4e2Lj8IVy9yEYyrywEOC5XRW37KJjsiOAsumi1rkvM7QREWgUDe Xs0+RpxI3QrrANh71fLMRo7LKRF3Gvw13NVCCC9ea20P4PwhgWKStkwO2NO+YJsAoS1QycMi/vKu 0EHhknYXamaSV50oZzHKmX56vEeJHTcngrM8R1SwJCYopCx9gkz90bTVYlitJa5hloWTYeMD7FNj Y6jfVSzgM/K4gMgUNDW/PPGeMwARAQABwsF2BBgBCAAgFiEEgnQYxPSsWOdyMMRzNHYf+OetQ9IF AmiDvXgCGwwACgkQNHYf+OetQ9LHDBAAhk+ab8+WrbS/b1/gYW3q1KDiXU719nCtfkUVXKidW5Ec Idlr5HGt8ilLoxSWT2Zi368iHCXS0WenGgPwlv8ifvB7TOZiiTDZROZkXjEBmU4nYjJ7GymawpWv oQwjMsPuq6ysbzWtOZ7eILx7cI0FjQeJ/Q2baRJub0uAZNwBOxCkAS6lpk5Fntd2u8CWmDQo4SYp xeuQ+pwkp0yEP30RhN2BO2DXiBEGSZSYh+ioGbCHQPIV3iVj0h6lcCPOqopZqyeCfigeacBI0nvN jHWz/spzF3+4OS+3RJvoHtAQmProxyGib8iVsTxgZO3UUi4TSODeEt0i0kHSPY4sCciOyXfAyYoD DFqhRjOEwBBxhr+scU4C1T2AflozvDwq3VSONjrKJUkhd8+WsdXxMdPFgBQuiKKwUy11mz6KQfcR wmDehF3UaUoxa+YIhWPbKmycxuX/D8SvnqavzAeAL1OcRbEI/HsoroVlEFbBRNBZLJUlnTPs8ZcU 4+8rq5YX1GUrJL3jf6SAfSgO7UdkEET3PdcKFYtS+ruV1Cp5V0q4kCfI5jk25iiz8grM2wOzVSsc l1mEkhiEPH87HP0whhb544iioSnumd3HJKL7dzhRegsMizatupp8D65A2JziW0WKopa1iw9fti3A aBeNN4ijKZchBXHPgVx+YtWRHfcm4l8= OpenPGP: url=https://posteo.de/keys/markus.probst@posteo.de.asc; preference=encrypt Implement the abstractions needed for multicolor led class devices, including: * `led::MultiColor` - the led mode implementation * `MultiColorSubLed` - a safe wrapper arround `mc_subled` * `led::Device::new_multicolor()` - the function to register a multicolor led class device * `led::Device::subleds()` - the function to access the brightness and intensity of the individual sub leds Signed-off-by: Markus Probst --- rust/bindings/bindings_helper.h | 1 + rust/kernel/led.rs | 7 +- rust/kernel/led/multicolor.rs | 195 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 202 insertions(+), 1 deletion(-) diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h index 2e43c66635a2..ba8605eeecce 100644 --- a/rust/bindings/bindings_helper.h +++ b/rust/bindings/bindings_helper.h @@ -61,6 +61,7 @@ #include #include #include +#include #include #include #include diff --git a/rust/kernel/led.rs b/rust/kernel/led.rs index c55f9852d378..4add9d15a5e0 100644 --- a/rust/kernel/led.rs +++ b/rust/kernel/led.rs @@ -44,8 +44,12 @@ }, // }; +#[cfg(CONFIG_LEDS_CLASS_MULTICOLOR)] +mod multicolor; mod normal; +#[cfg(CONFIG_LEDS_CLASS_MULTICOLOR)] +pub use multicolor::{MultiColor, MultiColorSubLed}; pub use normal::Normal; /// The led class device representation. @@ -288,7 +292,8 @@ fn try_from(value: u32) -> core::result::Result { /// /// Each led mode has its own led class device type with different capabilities. /// -/// See [`Normal`]. +#[cfg_attr(CONFIG_LEDS_CLASS_MULTICOLOR, doc = "See [`Normal`] and [`MultiColor`].")] +#[cfg_attr(not(CONFIG_LEDS_CLASS_MULTICOLOR), doc = "See [`Normal`] and `MultiColor`.")] pub trait Mode: private::Mode {} impl Mode for T {} diff --git a/rust/kernel/led/multicolor.rs b/rust/kernel/led/multicolor.rs new file mode 100644 index 000000000000..3afefaef6498 --- /dev/null +++ b/rust/kernel/led/multicolor.rs @@ -0,0 +1,195 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Led mode for the `struct led_classdev_mc`. +//! +//! C header: [`include/linux/led-class-multicolor.h`](srctree/include/linux/led-class-multicolor.h) + +use crate::{ + alloc::KVec, + error::code::EINVAL, + prelude::*, // +}; + +use super::*; + +/// The led mode for the `struct led_classdev_mc`. Leds with this mode can have multiple colors. +pub enum MultiColor {} + +/// The multicolor sub led info representation. +/// +/// This structure represents the Rust abstraction for a C `struct mc_subled`. +#[repr(C)] +#[derive(Copy, Clone, Debug)] +pub struct MultiColorSubLed { + /// the color of the sub led + pub color: Color, + /// the brightness of the sub led. + /// + /// The value will be automatically calculated. + /// See `MultiColor::pre_brightness_set`. + pub brightness: u32, + /// the intensity of the sub led. + pub intensity: u32, + /// arbitrary data for the driver to store. + pub channel: u32, + _p: PhantomData<()>, // Only allow creation with `MultiColorSubLed::new`. +} + +// We directly pass a reference to the `subled_info` field in `led_classdev_mc` to the driver via +// `Device::subleds()`. +// We need safeguards to ensure `MultiColorSubLed` and `mc_subled` stay identical. +const _: () = { + use core::mem::offset_of; + + const fn assert_same_type(_: &T, _: &T) {} + + let rust_zeroed = MultiColorSubLed { + color: Color::White, + brightness: 0, + intensity: 0, + channel: 0, + _p: PhantomData, + }; + let c_zeroed = bindings::mc_subled { + color_index: 0, + brightness: 0, + intensity: 0, + channel: 0, + }; + + assert!(offset_of!(MultiColorSubLed, color) == offset_of!(bindings::mc_subled, color_index)); + assert_same_type(&0u32, &c_zeroed.color_index); + + assert!( + offset_of!(MultiColorSubLed, brightness) == offset_of!(bindings::mc_subled, brightness) + ); + assert_same_type(&rust_zeroed.brightness, &c_zeroed.brightness); + + assert!(offset_of!(MultiColorSubLed, intensity) == offset_of!(bindings::mc_subled, intensity)); + assert_same_type(&rust_zeroed.intensity, &c_zeroed.intensity); + + assert!(offset_of!(MultiColorSubLed, channel) == offset_of!(bindings::mc_subled, channel)); + assert_same_type(&rust_zeroed.channel, &c_zeroed.channel); + + assert!(size_of::() == size_of::()); +}; + +impl MultiColorSubLed { + /// Create a new multicolor sub led info. + pub fn new(color: Color) -> Self { + Self { + color, + brightness: 0, + intensity: 0, + channel: 0, + _p: PhantomData, + } + } + + /// Set arbitrary data for the driver. + pub fn channel(mut self, channel: u32) -> Self { + self.channel = channel; + self + } + + /// Set the initial intensity of the subled. + pub fn initial_intensity(mut self, intensity: u32) -> Self { + self.intensity = intensity; + self + } +} + +impl private::Mode for MultiColor { + type Type = bindings::led_classdev_mc; + const REGISTER: RegisterFunc = bindings::led_classdev_multicolor_register_ext; + const UNREGISTER: UnregisterFunc = bindings::led_classdev_multicolor_unregister; + + unsafe fn device<'a>(raw: *mut Self::Type) -> &'a device::Device { + // SAFETY: + // - The function's contract guarantees that `raw` is a valid pointer to `led_classdev`. + unsafe { device::Device::from_raw((*raw).led_cdev.dev) } + } + + unsafe fn from_classdev(led_cdev: *mut bindings::led_classdev) -> *mut Self::Type { + // SAFETY: The function's contract guarantees that `led_cdev` is a valid pointer to + // `led_classdev` embedded within a `Self::Type`. + unsafe { container_of!(led_cdev, bindings::led_classdev_mc, led_cdev) } + } + + unsafe fn pre_brightness_set(raw: *mut Self::Type, brightness: u32) { + // SAFETY: The function's contract guarantees that `raw` is a valid pointer to + // `led_classdev_mc`. + unsafe { bindings::led_mc_calc_color_components(raw, brightness) }; + } + + fn release(led_cdev: &mut Self::Type) { + // SAFETY: `subled_info` is guaranteed to be a valid array pointer to `mc_subled` with the + // length and capacity of `led_cdev.num_colors`. See `led::Device::new_multicolor`. + let _subleds_vec = unsafe { + KVec::from_raw_parts( + led_cdev.subled_info, + led_cdev.num_colors as usize, + led_cdev.num_colors as usize, + ) + }; + } +} + +impl> Device { + /// Registers a new multicolor led classdev. + /// + /// The [`Device`] will be unregistered on drop. + pub fn new_multicolor<'a>( + parent: &'a T::Bus, + init_data: InitData<'a>, + ops: T, + subleds: &'a [MultiColorSubLed], + ) -> impl PinInit, Error> + 'a { + assert!(subleds.len() <= u32::MAX as usize); + Self::__new(parent, init_data, ops, |led_cdev| { + let mut subleds_vec = KVec::new(); + subleds_vec.extend_from_slice(subleds, GFP_KERNEL)?; + let (subled_info, num_colors, capacity) = subleds_vec.into_raw_parts(); + debug_assert_eq!(num_colors, capacity); + + let mut used = 0; + if subleds.iter().any(|subled| { + let bit = 1 << (subled.color as u32); + if (used & bit) != 0 { + true + } else { + used |= bit; + false + } + }) { + dev_err!(parent.as_ref(), "duplicate color in multicolor led\n"); + return Err(EINVAL); + } + + Ok(bindings::led_classdev_mc { + led_cdev, + // CAST: We checked above that the length of subleds fits into a u32. + num_colors: num_colors as u32, + // CAST: The safeguards in the const block ensure that `MultiColorSubLed` has an + // identical layout to `mc_subled`. + subled_info: subled_info.cast::(), + }) + }) + } + + /// Returns the subleds passed to [`Device::new_multicolor`]. + pub fn subleds(&self) -> &[MultiColorSubLed] { + // SAFETY: The existence of `self` guarantees that `self.classdev.get()` is a pointer to a + // valid `led_classdev_mc`. + let raw = unsafe { &*self.classdev.get() }; + // SAFETY: `raw.subled_info` is a valid pointer to `mc_subled[num_colors]`. + // CAST: The safeguards in the const block ensure that `MultiColorSubLed` has an identical + // layout to `mc_subled`. + unsafe { + core::slice::from_raw_parts( + raw.subled_info.cast::(), + raw.num_colors as usize, + ) + } + } +} -- 2.51.0