[PATCH] rust: kernel: device: Add of_platform_populate/depopulate

Ayush Singh
2025-04-28T14:22:51Z

Add abstractions for managed of_platform_populate and
of_platform_depopulate.

Signed-off-by: Ayush Singh <ayush@beagleboard.org>
---
Allow calling platform_populate/depopulate from Rust code.

To see how the bindings look in usage, see my working tree [0] for a
connector driver I am working on.

Open Questions
***************

1. Function names

The rust implementations are based on devm_* versions of these
functions, i.e of_platform_depopulate() is called when the device is
unbound. Since in case of Rust, these are methods on the Device struct,
I am not sure if the `devm_` prefix is required.

2. Maybe should be functions instead of methods?

Not sure what the policy is regarding this.

[0]: https://github.com/Ayush1325/linux/commits/b4/beagle-cape/
---
rust/bindings/bindings_helper.h | 1 +
rust/kernel/device.rs | 10 ++++++++++
2 files changed, 11 insertions(+)

diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h
index 8a2add69e5d66d1c2ebed9d2c950380e61c48842..51ec0754960377e5fc6bc0703487bf2086eff0e6 100644
--- a/rust/bindings/bindings_helper.h
+++ b/rust/bindings/bindings_helper.h
@@ -25,6 +25,7 @@
#include <linux/mdio.h>
#include <linux/miscdevice.h>
#include <linux/of_device.h>
+#include <linux/of_platform.h>
#include <linux/pci.h>
#include <linux/phy.h>
#include <linux/pid_namespace.h>
diff --git a/rust/kernel/device.rs b/rust/kernel/device.rs
index 40c1f549b0bae9fd9aa3f41539ccb69896c2560d..7186fe9658ff2a143a43bd6b3500c9a6d6ef9630 100644
--- a/rust/kernel/device.rs
+++ b/rust/kernel/device.rs
@@ -207,6 +207,16 @@ pub fn property_present(&self, name: &CStr) -> bool {
// SAFETY: By the invariant of `CStr`, `name` is null-terminated.
unsafe { bindings::device_property_present(self.as_raw().cast_const(), name.as_char_ptr()) }
}
+
+ /// Populate platform_devices from device tree data
+ pub fn of_platform_populate(&self) -> crate::error::Result<()> {
+ crate::error::to_result(unsafe { bindings::devm_of_platform_populate(self.as_raw()) })
+ }
+
+ /// Remove devices populated from device tree
+ pub fn of_platform_depopulate(&self) {
+ unsafe { bindings::devm_of_platform_depopulate(self.as_raw()) }
+ }
}

// SAFETY: `Device` is a transparent wrapper of a type that doesn't depend on `Device`'s generic

---
base-commit: 33035b665157558254b3c21c3f049fd728e72368
change-id: 20250428-rust-of-populate-b2f961783441

Best regards,
--
Ayush Singh <ayush@beagleboard.org>