rust: module: introduce authors key

In the `module!` macro, the `author` field is currently of type `String`.

Since modules can have multiple authors, this limitation prevents
specifying more than one.

Add an `authors` field as `Option<Vec<String>>` to allow creating
modules with multiple authors, and change the documentation and all
current users to use it. Eventually, the single `author` field may
be removed.

[ The `modinfo` key needs to still be `author`; otherwise, tooling
  may not work properly, e.g.:

      $ modinfo --author samples/rust/rust_print.ko
      Rust for Linux Contributors

  I have also kept the original `author` field (undocumented), so
  that we can drop it more easily in a kernel cycle or two.

    - Miguel ]

Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/244
Reviewed-by: Charalampos Mitrodimas <charmitro@posteo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: Guilherme Giacomo Simoes <trintaeoitogc@gmail.com>
Link: https://lore.kernel.org/r/20250309175712.845622-2-trintaeoitogc@gmail.com
[ Fixed `modinfo` key. Kept `author` field. Reworded message
  accordingly. Updated my email. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

drivers/block/rnull.rs

@@ -27,7 +27,7 @@
 module! {
     type: NullBlkModule,
     name: "rnull_mod",
-    author: "Andreas Hindborg",
+    authors: ["Andreas Hindborg"],
     description: "Rust implementation of the C null block driver",
     license: "GPL v2",
 }

drivers/net/phy/ax88796b_rust.rs

@@ -19,7 +19,7 @@
         DeviceId::new_with_driver::<PhyAX88796B>()
     ],
     name: "rust_asix_phy",
-    author: "FUJITA Tomonori <fujita.tomonori@gmail.com>",
+    authors: ["FUJITA Tomonori <fujita.tomonori@gmail.com>"],
     description: "Rust Asix PHYs driver",
     license: "GPL",
 }

drivers/net/phy/qt2025.rs

@@ -26,7 +26,7 @@
         phy::DeviceId::new_with_driver::<PhyQT2025>(),
     ],
     name: "qt2025_phy",
-    author: "FUJITA Tomonori <fujita.tomonori@gmail.com>",
+    authors: ["FUJITA Tomonori <fujita.tomonori@gmail.com>"],
     description: "AMCC QT2025 PHY driver",
     license: "GPL",
     firmware: ["qt2025-2.0.3.3.fw"],

rust/kernel/net/phy.rs

@@ -790,7 +790,7 @@ const fn as_int(&self) -> u32 {
 ///         DeviceId::new_with_driver::<PhySample>()
 ///     ],
 ///     name: "rust_sample_phy",
-///     author: "Rust for Linux Contributors",
+///     authors: ["Rust for Linux Contributors"],
 ///     description: "Rust sample PHYs driver",
 ///     license: "GPL",
 /// }
@@ -819,7 +819,7 @@ const fn as_int(&self) -> u32 {
 /// module! {
 ///     type: Module,
 ///     name: "rust_sample_phy",
-///     author: "Rust for Linux Contributors",
+///     authors: ["Rust for Linux Contributors"],
 ///     description: "Rust sample PHYs driver",
 ///     license: "GPL",
 /// }

rust/kernel/pci.rs

@@ -103,7 +103,7 @@ extern "C" fn remove_callback(pdev: *mut bindings::pci_dev) {
 /// kernel::module_pci_driver! {
 ///     type: MyDriver,
 ///     name: "Module name",
-///     author: "Author name",
+///     authors: ["Author name"],
 ///     description: "Description",
 ///     license: "GPL v2",
 /// }

rust/kernel/platform.rs

@@ -101,7 +101,7 @@ fn of_id_table() -> Option<of::IdTable<Self::IdInfo>> {
 /// kernel::module_platform_driver! {
 ///     type: MyDriver,
 ///     name: "Module name",
-///     author: "Author name",
+///     authors: ["Author name"],
 ///     description: "Description",
 ///     license: "GPL v2",
 /// }

rust/macros/lib.rs

@@ -37,7 +37,7 @@
 /// module!{
 ///     type: MyModule,
 ///     name: "my_kernel_module",
-///     author: "Rust for Linux Contributors",
+///     authors: ["Rust for Linux Contributors"],
 ///     description: "My very own kernel module!",
 ///     license: "GPL",
 ///     alias: ["alternate_module_name"],
@@ -70,7 +70,7 @@
 /// module!{
 ///     type: MyDeviceDriverModule,
 ///     name: "my_device_driver_module",
-///     author: "Rust for Linux Contributors",
+///     authors: ["Rust for Linux Contributors"],
 ///     description: "My device driver requires firmware",
 ///     license: "GPL",
 ///     firmware: ["my_device_firmware1.bin", "my_device_firmware2.bin"],
@@ -89,7 +89,7 @@
 /// # Supported argument types
 ///   - `type`: type which implements the [`Module`] trait (required).
 ///   - `name`: ASCII string literal of the name of the kernel module (required).
-///   - `author`: string literal of the author of the kernel module.
+///   - `authors`: array of ASCII string literals of the authors of the kernel module.
 ///   - `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.

rust/macros/module.rs

@@ -95,6 +95,7 @@ struct ModuleInfo {
     license: String,
     name: String,
     author: Option<String>,
+    authors: Option<Vec<String>>,
     description: Option<String>,
     alias: Option<Vec<String>>,
     firmware: Option<Vec<String>>,
@@ -108,6 +109,7 @@ fn parse(it: &mut token_stream::IntoIter) -> Self {
             "type",
             "name",
             "author",
+            "authors",
             "description",
             "license",
             "alias",
@@ -136,6 +138,7 @@ fn parse(it: &mut token_stream::IntoIter) -> Self {
                 "type" => info.type_ = expect_ident(it),
                 "name" => info.name = expect_string_ascii(it),
                 "author" => info.author = Some(expect_string(it)),
+                "authors" => info.authors = Some(expect_string_array(it)),
                 "description" => info.description = Some(expect_string(it)),
                 "license" => info.license = expect_string_ascii(it),
                 "alias" => info.alias = Some(expect_string_array(it)),
@@ -186,6 +189,11 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
     if let Some(author) = info.author {
         modinfo.emit("author", &author);
     }
+    if let Some(authors) = info.authors {
+        for author in authors {
+            modinfo.emit("author", &author);
+        }
+    }
     if let Some(description) = info.description {
         modinfo.emit("description", &description);
     }

samples/rust/rust_driver_faux.rs

@@ -7,7 +7,7 @@
 module! {
     type: SampleModule,
     name: "rust_faux_driver",
-    author: "Lyude Paul",
+    authors: ["Lyude Paul"],
     description: "Rust faux device sample",
     license: "GPL",
 }

samples/rust/rust_driver_pci.rs

@@ -104,7 +104,7 @@ fn drop(&mut self) {
 kernel::module_pci_driver! {
     type: SampleDriver,
     name: "rust_driver_pci",
-    author: "Danilo Krummrich",
+    authors: ["Danilo Krummrich"],
     description: "Rust PCI driver",
     license: "GPL v2",
 }

samples/rust/rust_driver_platform.rs

@@ -43,7 +43,7 @@ fn drop(&mut self) {
 kernel::module_platform_driver! {
     type: SampleDriver,
     name: "rust_driver_platform",
-    author: "Danilo Krummrich",
+    authors: ["Danilo Krummrich"],
     description: "Rust Platform driver",
     license: "GPL v2",
 }

samples/rust/rust_minimal.rs

@@ -7,7 +7,7 @@
 module! {
     type: RustMinimal,
     name: "rust_minimal",
-    author: "Rust for Linux Contributors",
+    authors: ["Rust for Linux Contributors"],
     description: "Rust minimal sample",
     license: "GPL",
 }

samples/rust/rust_misc_device.rs

@@ -116,7 +116,7 @@
 module! {
     type: RustMiscDeviceModule,
     name: "rust_misc_device",
-    author: "Lee Jones",
+    authors: ["Lee Jones"],
     description: "Rust misc device sample",
     license: "GPL",
 }

samples/rust/rust_print_main.rs

@@ -8,7 +8,7 @@
 module! {
     type: RustPrint,
     name: "rust_print",
-    author: "Rust for Linux Contributors",
+    authors: ["Rust for Linux Contributors"],
     description: "Rust printing macros sample",
     license: "GPL",
 }