rust: add 'firmware' field support to module! macro

This adds 'firmware' field support to module! macro, corresponds to
MODULE_FIRMWARE macro. You can specify the file names of binary
firmware that the kernel module requires. The information is embedded
in the modinfo section of the kernel module. For example, a tool to
build an initramfs uses this information to put the firmware files
into the initramfs image.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240501123548.51769-1-fujita.tomonori@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

1 files changed, 32 insertions, 0 deletions

diff --git a/rust/macros/lib.rs b/rust/macros/lib.rs
index 5214e07367c5..6dcc72aff111 100644
--- a/rust/macros/lib.rs
+++ b/rust/macros/lib.rs
@@ -56,6 +56,36 @@ use proc_macro::TokenStream;
 /// }
 /// ```
 ///
+/// ## Firmware
+///
+/// The following example shows how to declare a kernel module that needs
+/// to load binary firmware files. You need to specify the file names of
+/// the firmware in the `firmware` field. The information is embedded
+/// in the `modinfo` section of the kernel module. For example, a tool to
+/// build an initramfs uses this information to put the firmware files into
+/// the initramfs image.
+///
+/// ```ignore
+/// use kernel::prelude::*;
+///
+/// module!{
+///     type: MyDeviceDriverModule,
+///     name: "my_device_driver_module",
+///     author: "Rust for Linux Contributors",
+///     description: "My device driver requires firmware",
+///     license: "GPL",
+///     firmware: ["my_device_firmware1.bin", "my_device_firmware2.bin"],
+/// }
+///
+/// struct MyDeviceDriverModule;
+///
+/// impl kernel::Module for MyDeviceDriverModule {
+///     fn init() -> Result<Self> {
+///         Ok(Self)
+///     }
+/// }
+/// ```
+///
 /// # Supported argument types
 ///   - `type`: type which implements the [`Module`] trait (required).
 ///   - `name`: ASCII string literal of the name of the kernel module (required).
@@ -63,6 +93,8 @@ use proc_macro::TokenStream;
 ///   - `description`: string literal of the description of the kernel module.
 ///   - `license`: ASCII string literal of the license of the kernel module (required).
 ///   - `alias`: array of ASCII string literals of the alias names of the kernel module.
+///   - `firmware`: array of ASCII string literals of the firmware files of
+/// the kernel module.
 #[proc_macro]
 pub fn module(ts: TokenStream) -> TokenStream {
     module::module(ts)