From 2692c614f8f05929d692b3dbfd3faef1f00fbaf0 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Tue, 10 Feb 2026 14:58:22 +0100 Subject: [PATCH 1/3] device property: Allow secondary lookup in fwnode_get_next_child_node() When device_get_child_node_count() got split to the fwnode and device respective APIs, the fwnode didn't inherit the ability to traverse over the secondary fwnode. Hence any user, that switches from device to fwnode API misses this feature. In particular, this was revealed by the commit 1490cbb9dbfd ("device property: Split fwnode_get_child_node_count()") that effectively broke the GPIO enumeration on Intel Galileo boards. Fix this by moving the secondary lookup from device to fwnode API. Note, in general no device_*() API should go into the depth of the fwnode implementation. Fixes: 114dbb4fa7c4 ("drivers property: When no children in primary, try secondary") Cc: stable@vger.kernel.org Signed-off-by: Andy Shevchenko Reviewed-by: Rafael J. Wysocki (Intel) Reviewed-by: Sakari Ailus Link: https://patch.msgid.link/20260210135822.47335-1-andriy.shevchenko@linux.intel.com Signed-off-by: Danilo Krummrich --- drivers/base/property.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) diff --git a/drivers/base/property.c b/drivers/base/property.c index 6a63860579dd..8d9a34be57fb 100644 --- a/drivers/base/property.c +++ b/drivers/base/property.c @@ -797,7 +797,18 @@ struct fwnode_handle * fwnode_get_next_child_node(const struct fwnode_handle *fwnode, struct fwnode_handle *child) { - return fwnode_call_ptr_op(fwnode, get_next_child_node, child); + struct fwnode_handle *next; + + if (IS_ERR_OR_NULL(fwnode)) + return NULL; + + /* Try to find a child in primary fwnode */ + next = fwnode_call_ptr_op(fwnode, get_next_child_node, child); + if (next) + return next; + + /* When no more children in primary, continue with secondary */ + return fwnode_call_ptr_op(fwnode->secondary, get_next_child_node, child); } EXPORT_SYMBOL_GPL(fwnode_get_next_child_node); @@ -841,19 +852,7 @@ EXPORT_SYMBOL_GPL(fwnode_get_next_available_child_node); struct fwnode_handle *device_get_next_child_node(const struct device *dev, struct fwnode_handle *child) { - const struct fwnode_handle *fwnode = dev_fwnode(dev); - struct fwnode_handle *next; - - if (IS_ERR_OR_NULL(fwnode)) - return NULL; - - /* Try to find a child in primary fwnode */ - next = fwnode_get_next_child_node(fwnode, child); - if (next) - return next; - - /* When no more children in primary, continue with secondary */ - return fwnode_get_next_child_node(fwnode->secondary, child); + return fwnode_get_next_child_node(dev_fwnode(dev), child); } EXPORT_SYMBOL_GPL(device_get_next_child_node); From bfcaf4e8ae9b4f52b97fb04ce03be3a01d41cdd0 Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Mon, 16 Feb 2026 14:14:33 +0100 Subject: [PATCH 2/3] rust: io: macro_export io_define_read!() and io_define_write!() Currently, the define_read!() and define_write!() I/O macros are crate public. The only user outside of the I/O module is PCI (for the configurations space I/O backend). Consequently, when CONFIG_PCI=n this causes a compile time warning [1]. In order to fix this, rename the macros to io_define_read!() and io_define_write!() and use #[macro_export] to export them. This is better than making the crate public visibility conditional, as eventually subsystems will have their own crate. Also, I/O backends are valid to be implemented by drivers as well. For instance, there are devices (such as GPUs) that run firmware which allows to program other devices only accessible through the primary device through indirect I/O. Since the macros are now public, also add the corresponding documentation. Fixes: 121d87b28e1d ("rust: io: separate generic I/O helpers from MMIO implementation") Reported-by: Miguel Ojeda Closes: https://lore.kernel.org/driver-core/CANiq72khOYkt6t5zwMvSiyZvWWHMZuNCMERXu=7K=_5tT-8Pgg@mail.gmail.com/ [1] Reviewed-by: Alice Ryhl Reviewed-by: Daniel Almeida Link: https://patch.msgid.link/20260216131534.65008-1-dakr@kernel.org Signed-off-by: Danilo Krummrich --- rust/kernel/io.rs | 131 ++++++++++++++++++++++++++++-------------- rust/kernel/pci/io.rs | 24 ++++---- 2 files changed, 101 insertions(+), 54 deletions(-) diff --git a/rust/kernel/io.rs b/rust/kernel/io.rs index c1cca7b438c3..e5fba6bf6db0 100644 --- a/rust/kernel/io.rs +++ b/rust/kernel/io.rs @@ -139,9 +139,9 @@ pub struct Mmio(MmioRaw); /// Internal helper macros used to invoke C MMIO read functions. /// -/// This macro is intended to be used by higher-level MMIO access macros (define_read) and provides -/// a unified expansion for infallible vs. fallible read semantics. It emits a direct call into the -/// corresponding C helper and performs the required cast to the Rust return type. +/// This macro is intended to be used by higher-level MMIO access macros (io_define_read) and +/// provides a unified expansion for infallible vs. fallible read semantics. It emits a direct call +/// into the corresponding C helper and performs the required cast to the Rust return type. /// /// # Parameters /// @@ -166,9 +166,9 @@ macro_rules! call_mmio_read { /// Internal helper macros used to invoke C MMIO write functions. /// -/// This macro is intended to be used by higher-level MMIO access macros (define_write) and provides -/// a unified expansion for infallible vs. fallible write semantics. It emits a direct call into the -/// corresponding C helper and performs the required cast to the Rust return type. +/// This macro is intended to be used by higher-level MMIO access macros (io_define_write) and +/// provides a unified expansion for infallible vs. fallible write semantics. It emits a direct call +/// into the corresponding C helper and performs the required cast to the Rust return type. /// /// # Parameters /// @@ -193,7 +193,30 @@ macro_rules! call_mmio_write { }}; } -macro_rules! define_read { +/// Generates an accessor method for reading from an I/O backend. +/// +/// This macro reduces boilerplate by automatically generating either compile-time bounds-checked +/// (infallible) or runtime bounds-checked (fallible) read methods. It abstracts the address +/// calculation and bounds checking, and delegates the actual I/O read operation to a specified +/// helper macro, making it generic over different I/O backends. +/// +/// # Parameters +/// +/// * `infallible` / `fallible` - Determines the bounds-checking strategy. `infallible` relies on +/// `IoKnownSize` for compile-time checks and returns the value directly. `fallible` performs +/// runtime checks against `maxsize()` and returns a `Result`. +/// * `$(#[$attr:meta])*` - Optional attributes to apply to the generated method (e.g., +/// `#[cfg(CONFIG_64BIT)]` or inline directives). +/// * `$vis:vis` - The visibility of the generated method (e.g., `pub`). +/// * `$name:ident` / `$try_name:ident` - The name of the generated method (e.g., `read32`, +/// `try_read8`). +/// * `$call_macro:ident` - The backend-specific helper macro used to emit the actual I/O call +/// (e.g., `call_mmio_read`). +/// * `$c_fn:ident` - The backend-specific C function or identifier to be passed into the +/// `$call_macro`. +/// * `$type_name:ty` - The Rust type of the value being read (e.g., `u8`, `u32`). +#[macro_export] +macro_rules! io_define_read { (infallible, $(#[$attr:meta])* $vis:vis $name:ident, $call_macro:ident($c_fn:ident) -> $type_name:ty) => { /// Read IO data from a given offset known at compile time. @@ -226,9 +249,33 @@ macro_rules! define_read { } }; } -pub(crate) use define_read; +pub use io_define_read; -macro_rules! define_write { +/// Generates an accessor method for writing to an I/O backend. +/// +/// This macro reduces boilerplate by automatically generating either compile-time bounds-checked +/// (infallible) or runtime bounds-checked (fallible) write methods. It abstracts the address +/// calculation and bounds checking, and delegates the actual I/O write operation to a specified +/// helper macro, making it generic over different I/O backends. +/// +/// # Parameters +/// +/// * `infallible` / `fallible` - Determines the bounds-checking strategy. `infallible` relies on +/// `IoKnownSize` for compile-time checks and returns `()`. `fallible` performs runtime checks +/// against `maxsize()` and returns a `Result`. +/// * `$(#[$attr:meta])*` - Optional attributes to apply to the generated method (e.g., +/// `#[cfg(CONFIG_64BIT)]` or inline directives). +/// * `$vis:vis` - The visibility of the generated method (e.g., `pub`). +/// * `$name:ident` / `$try_name:ident` - The name of the generated method (e.g., `write32`, +/// `try_write8`). +/// * `$call_macro:ident` - The backend-specific helper macro used to emit the actual I/O call +/// (e.g., `call_mmio_write`). +/// * `$c_fn:ident` - The backend-specific C function or identifier to be passed into the +/// `$call_macro`. +/// * `$type_name:ty` - The Rust type of the value being written (e.g., `u8`, `u32`). Note the use +/// of `<-` before the type to denote a write operation. +#[macro_export] +macro_rules! io_define_write { (infallible, $(#[$attr:meta])* $vis:vis $name:ident, $call_macro:ident($c_fn:ident) <- $type_name:ty) => { /// Write IO data from a given offset known at compile time. @@ -259,7 +306,7 @@ macro_rules! define_write { } }; } -pub(crate) use define_write; +pub use io_define_write; /// Checks whether an access of type `U` at the given `offset` /// is valid within this region. @@ -509,40 +556,40 @@ impl Io for Mmio { self.0.maxsize() } - define_read!(fallible, try_read8, call_mmio_read(readb) -> u8); - define_read!(fallible, try_read16, call_mmio_read(readw) -> u16); - define_read!(fallible, try_read32, call_mmio_read(readl) -> u32); - define_read!( + io_define_read!(fallible, try_read8, call_mmio_read(readb) -> u8); + io_define_read!(fallible, try_read16, call_mmio_read(readw) -> u16); + io_define_read!(fallible, try_read32, call_mmio_read(readl) -> u32); + io_define_read!( fallible, #[cfg(CONFIG_64BIT)] try_read64, call_mmio_read(readq) -> u64 ); - define_write!(fallible, try_write8, call_mmio_write(writeb) <- u8); - define_write!(fallible, try_write16, call_mmio_write(writew) <- u16); - define_write!(fallible, try_write32, call_mmio_write(writel) <- u32); - define_write!( + io_define_write!(fallible, try_write8, call_mmio_write(writeb) <- u8); + io_define_write!(fallible, try_write16, call_mmio_write(writew) <- u16); + io_define_write!(fallible, try_write32, call_mmio_write(writel) <- u32); + io_define_write!( fallible, #[cfg(CONFIG_64BIT)] try_write64, call_mmio_write(writeq) <- u64 ); - define_read!(infallible, read8, call_mmio_read(readb) -> u8); - define_read!(infallible, read16, call_mmio_read(readw) -> u16); - define_read!(infallible, read32, call_mmio_read(readl) -> u32); - define_read!( + io_define_read!(infallible, read8, call_mmio_read(readb) -> u8); + io_define_read!(infallible, read16, call_mmio_read(readw) -> u16); + io_define_read!(infallible, read32, call_mmio_read(readl) -> u32); + io_define_read!( infallible, #[cfg(CONFIG_64BIT)] read64, call_mmio_read(readq) -> u64 ); - define_write!(infallible, write8, call_mmio_write(writeb) <- u8); - define_write!(infallible, write16, call_mmio_write(writew) <- u16); - define_write!(infallible, write32, call_mmio_write(writel) <- u32); - define_write!( + io_define_write!(infallible, write8, call_mmio_write(writeb) <- u8); + io_define_write!(infallible, write16, call_mmio_write(writew) <- u16); + io_define_write!(infallible, write32, call_mmio_write(writel) <- u32); + io_define_write!( infallible, #[cfg(CONFIG_64BIT)] write64, @@ -566,40 +613,40 @@ impl Mmio { unsafe { &*core::ptr::from_ref(raw).cast() } } - define_read!(infallible, pub read8_relaxed, call_mmio_read(readb_relaxed) -> u8); - define_read!(infallible, pub read16_relaxed, call_mmio_read(readw_relaxed) -> u16); - define_read!(infallible, pub read32_relaxed, call_mmio_read(readl_relaxed) -> u32); - define_read!( + io_define_read!(infallible, pub read8_relaxed, call_mmio_read(readb_relaxed) -> u8); + io_define_read!(infallible, pub read16_relaxed, call_mmio_read(readw_relaxed) -> u16); + io_define_read!(infallible, pub read32_relaxed, call_mmio_read(readl_relaxed) -> u32); + io_define_read!( infallible, #[cfg(CONFIG_64BIT)] pub read64_relaxed, call_mmio_read(readq_relaxed) -> u64 ); - define_read!(fallible, pub try_read8_relaxed, call_mmio_read(readb_relaxed) -> u8); - define_read!(fallible, pub try_read16_relaxed, call_mmio_read(readw_relaxed) -> u16); - define_read!(fallible, pub try_read32_relaxed, call_mmio_read(readl_relaxed) -> u32); - define_read!( + io_define_read!(fallible, pub try_read8_relaxed, call_mmio_read(readb_relaxed) -> u8); + io_define_read!(fallible, pub try_read16_relaxed, call_mmio_read(readw_relaxed) -> u16); + io_define_read!(fallible, pub try_read32_relaxed, call_mmio_read(readl_relaxed) -> u32); + io_define_read!( fallible, #[cfg(CONFIG_64BIT)] pub try_read64_relaxed, call_mmio_read(readq_relaxed) -> u64 ); - define_write!(infallible, pub write8_relaxed, call_mmio_write(writeb_relaxed) <- u8); - define_write!(infallible, pub write16_relaxed, call_mmio_write(writew_relaxed) <- u16); - define_write!(infallible, pub write32_relaxed, call_mmio_write(writel_relaxed) <- u32); - define_write!( + io_define_write!(infallible, pub write8_relaxed, call_mmio_write(writeb_relaxed) <- u8); + io_define_write!(infallible, pub write16_relaxed, call_mmio_write(writew_relaxed) <- u16); + io_define_write!(infallible, pub write32_relaxed, call_mmio_write(writel_relaxed) <- u32); + io_define_write!( infallible, #[cfg(CONFIG_64BIT)] pub write64_relaxed, call_mmio_write(writeq_relaxed) <- u64 ); - define_write!(fallible, pub try_write8_relaxed, call_mmio_write(writeb_relaxed) <- u8); - define_write!(fallible, pub try_write16_relaxed, call_mmio_write(writew_relaxed) <- u16); - define_write!(fallible, pub try_write32_relaxed, call_mmio_write(writel_relaxed) <- u32); - define_write!( + io_define_write!(fallible, pub try_write8_relaxed, call_mmio_write(writeb_relaxed) <- u8); + io_define_write!(fallible, pub try_write16_relaxed, call_mmio_write(writew_relaxed) <- u16); + io_define_write!(fallible, pub try_write32_relaxed, call_mmio_write(writel_relaxed) <- u32); + io_define_write!( fallible, #[cfg(CONFIG_64BIT)] pub try_write64_relaxed, diff --git a/rust/kernel/pci/io.rs b/rust/kernel/pci/io.rs index 6ca4cf75594c..fb6edab2aea7 100644 --- a/rust/kernel/pci/io.rs +++ b/rust/kernel/pci/io.rs @@ -8,8 +8,8 @@ use crate::{ device, devres::Devres, io::{ - define_read, - define_write, + io_define_read, + io_define_write, Io, IoCapable, IoKnownSize, @@ -88,7 +88,7 @@ pub struct ConfigSpace<'a, S: ConfigSpaceKind = Extended> { /// Internal helper macros used to invoke C PCI configuration space read functions. /// /// This macro is intended to be used by higher-level PCI configuration space access macros -/// (define_read) and provides a unified expansion for infallible vs. fallible read semantics. It +/// (io_define_read) and provides a unified expansion for infallible vs. fallible read semantics. It /// emits a direct call into the corresponding C helper and performs the required cast to the Rust /// return type. /// @@ -117,9 +117,9 @@ macro_rules! call_config_read { /// Internal helper macros used to invoke C PCI configuration space write functions. /// /// This macro is intended to be used by higher-level PCI configuration space access macros -/// (define_write) and provides a unified expansion for infallible vs. fallible read semantics. It -/// emits a direct call into the corresponding C helper and performs the required cast to the Rust -/// return type. +/// (io_define_write) and provides a unified expansion for infallible vs. fallible read semantics. +/// It emits a direct call into the corresponding C helper and performs the required cast to the +/// Rust return type. /// /// # Parameters /// @@ -163,13 +163,13 @@ impl<'a, S: ConfigSpaceKind> Io for ConfigSpace<'a, S> { // PCI configuration space does not support fallible operations. // The default implementations from the Io trait are not used. - define_read!(infallible, read8, call_config_read(pci_read_config_byte) -> u8); - define_read!(infallible, read16, call_config_read(pci_read_config_word) -> u16); - define_read!(infallible, read32, call_config_read(pci_read_config_dword) -> u32); + io_define_read!(infallible, read8, call_config_read(pci_read_config_byte) -> u8); + io_define_read!(infallible, read16, call_config_read(pci_read_config_word) -> u16); + io_define_read!(infallible, read32, call_config_read(pci_read_config_dword) -> u32); - define_write!(infallible, write8, call_config_write(pci_write_config_byte) <- u8); - define_write!(infallible, write16, call_config_write(pci_write_config_word) <- u16); - define_write!(infallible, write32, call_config_write(pci_write_config_dword) <- u32); + io_define_write!(infallible, write8, call_config_write(pci_write_config_byte) <- u8); + io_define_write!(infallible, write16, call_config_write(pci_write_config_word) <- u16); + io_define_write!(infallible, write32, call_config_write(pci_write_config_dword) <- u32); } impl<'a, S: ConfigSpaceKind> IoKnownSize for ConfigSpace<'a, S> { From 78437ab3b769f80526416570f60173c89858dd84 Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Fri, 13 Feb 2026 00:58:11 +0100 Subject: [PATCH 3/3] clk: scu/imx8qxp: do not register driver in probe() imx_clk_scu_init() registers the imx_clk_scu_driver while commonly being called from IMX driver's probe() callbacks. However, it neither makes sense to register drivers from probe() callbacks of other drivers, nor does the driver core allow registering drivers with a device lock already being held. The latter was revealed by commit dc23806a7c47 ("driver core: enforce device_lock for driver_match_device()") leading to a deadlock condition described in [1]. Besides that, nothing seems to unregister the imx_clk_scu_driver once the corresponding driver module is unloaded, which leaves the driver-core with a dangling pointer. Also, if there are multiple matching devices for the imx8qxp_clk_driver, imx8qxp_clk_probe() calls imx_clk_scu_init() multiple times. However, any subsequent call after the first one will fail, since the driver-core does not allow to register the same struct platform_driver multiple times. Hence, register the imx_clk_scu_driver from module_init() and unregister it in module_exit(). Note that we first register the imx8qxp_clk_driver and then call imx_clk_scu_module_init() to avoid having to call imx_clk_scu_module_exit() in the unwind path of imx8qxp_clk_init(). Fixes: dc23806a7c47 ("driver core: enforce device_lock for driver_match_device()") Fixes: 220175cd3979 ("clk: imx: scu: fix build break when compiled as modules") Reported-by: Alexander Stein Closes: https://lore.kernel.org/lkml/13955113.uLZWGnKmhe@steina-w/ Tested-by: Alexander Stein # TQMa8x/MBa8x Link: https://lore.kernel.org/lkml/DFU7CEPUSG9A.1KKGVW4HIPMSH@kernel.org/ [1] Acked-by: Abel Vesa Reviewed-by: Daniel Baluta Link: https://patch.msgid.link/20260212235842.85934-1-dakr@kernel.org Signed-off-by: Danilo Krummrich --- drivers/clk/imx/clk-imx8qxp.c | 24 +++++++++++++++++++++++- drivers/clk/imx/clk-scu.c | 12 +++++++++++- drivers/clk/imx/clk-scu.h | 2 ++ 3 files changed, 36 insertions(+), 2 deletions(-) diff --git a/drivers/clk/imx/clk-imx8qxp.c b/drivers/clk/imx/clk-imx8qxp.c index 3ae162625bb1..c781425a005e 100644 --- a/drivers/clk/imx/clk-imx8qxp.c +++ b/drivers/clk/imx/clk-imx8qxp.c @@ -346,7 +346,29 @@ static struct platform_driver imx8qxp_clk_driver = { }, .probe = imx8qxp_clk_probe, }; -module_platform_driver(imx8qxp_clk_driver); + +static int __init imx8qxp_clk_init(void) +{ + int ret; + + ret = platform_driver_register(&imx8qxp_clk_driver); + if (ret) + return ret; + + ret = imx_clk_scu_module_init(); + if (ret) + platform_driver_unregister(&imx8qxp_clk_driver); + + return ret; +} +module_init(imx8qxp_clk_init); + +static void __exit imx8qxp_clk_exit(void) +{ + imx_clk_scu_module_exit(); + platform_driver_unregister(&imx8qxp_clk_driver); +} +module_exit(imx8qxp_clk_exit); MODULE_AUTHOR("Aisheng Dong "); MODULE_DESCRIPTION("NXP i.MX8QXP clock driver"); diff --git a/drivers/clk/imx/clk-scu.c b/drivers/clk/imx/clk-scu.c index 33e637ad3579..a85ec48a798b 100644 --- a/drivers/clk/imx/clk-scu.c +++ b/drivers/clk/imx/clk-scu.c @@ -191,6 +191,16 @@ static bool imx_scu_clk_is_valid(u32 rsrc_id) return p != NULL; } +int __init imx_clk_scu_module_init(void) +{ + return platform_driver_register(&imx_clk_scu_driver); +} + +void __exit imx_clk_scu_module_exit(void) +{ + return platform_driver_unregister(&imx_clk_scu_driver); +} + int imx_clk_scu_init(struct device_node *np, const struct imx_clk_scu_rsrc_table *data) { @@ -215,7 +225,7 @@ int imx_clk_scu_init(struct device_node *np, rsrc_table = data; } - return platform_driver_register(&imx_clk_scu_driver); + return 0; } /* diff --git a/drivers/clk/imx/clk-scu.h b/drivers/clk/imx/clk-scu.h index af7b697f51ca..ca82f2cce897 100644 --- a/drivers/clk/imx/clk-scu.h +++ b/drivers/clk/imx/clk-scu.h @@ -25,6 +25,8 @@ extern const struct imx_clk_scu_rsrc_table imx_clk_scu_rsrc_imx8dxl; extern const struct imx_clk_scu_rsrc_table imx_clk_scu_rsrc_imx8qxp; extern const struct imx_clk_scu_rsrc_table imx_clk_scu_rsrc_imx8qm; +int __init imx_clk_scu_module_init(void); +void __exit imx_clk_scu_module_exit(void); int imx_clk_scu_init(struct device_node *np, const struct imx_clk_scu_rsrc_table *data); struct clk_hw *imx_scu_of_clk_src_get(struct of_phandle_args *clkspec,