1 // SPDX-License-Identifier: GPL-2.0
3 //! Firmware abstraction
5 //! C header: [`include/linux/firmware.h`](srctree/include/linux/firmware.h)
15     unsafe extern "C" fn(*mut *const bindings::firmware, *const i8, *mut bindings::device) -> i32,
19     fn request() -> Self {  in request()
23     fn request_nowarn() -> Self {  in request_nowarn()
28 /// Abstraction around a C `struct firmware`.
30 /// This is a simple abstraction around the C firmware API. Just like with the C API, firmware can
31 /// be requested. Once requested the abstraction provides direct access to the firmware buffer as
32 /// `&[u8]`. The firmware is released once [`Firmware`] is dropped.
36 /// The pointer is valid, and has ownership over the instance of `struct firmware`.
38 /// The `Firmware`'s backing buffer is not modified.
43 /// # use kernel::{c_str, device::Device, firmware::Firmware};
45 /// # fn no_run() -> Result<(), Error> {
49 /// let fw = Firmware::request(c_str!("path/to/firmware.bin"), &dev)?;
55 pub struct Firmware(NonNull<bindings::firmware>);  struct
57 impl Firmware {  impl
58     fn request_internal(name: &CStr, dev: &Device, func: FwFunc) -> Result<Self> {  in request_internal()
59         let mut fw: *mut bindings::firmware = core::ptr::null_mut();  in request_internal()
60         let pfw: *mut *mut bindings::firmware = &mut fw;  in request_internal()
62         // SAFETY: `pfw` is a valid pointer to a NULL initialized `bindings::firmware` pointer.  in request_internal()
63         // `name` and `dev` are valid as by their type invariants.  in request_internal()
64         let ret = unsafe { func.0(pfw as _, name.as_char_ptr(), dev.as_raw()) };  in request_internal()
69         // SAFETY: `func` not bailing out with a non-zero error code, guarantees that `fw` is a  in request_internal()
70         // valid pointer to `bindings::firmware`.  in request_internal()
71         Ok(Firmware(unsafe { NonNull::new_unchecked(fw) }))  in request_internal()
74     /// Send a firmware request and wait for it. See also `bindings::request_firmware`.
75     pub fn request(name: &CStr, dev: &Device) -> Result<Self> {  in request()
76         Self::request_internal(name, dev, FwFunc::request())  in request()
79     /// Send a request for an optional firmware module. See also
81     pub fn request_nowarn(name: &CStr, dev: &Device) -> Result<Self> {  in request_nowarn()
82         Self::request_internal(name, dev, FwFunc::request_nowarn())  in request_nowarn()
85     fn as_raw(&self) -> *mut bindings::firmware {  in as_raw()  argument
89     /// Returns the size of the requested firmware in bytes.
90     pub fn size(&self) -> usize {  in size()
95     /// Returns the requested firmware as `&[u8]`.
96     pub fn data(&self) -> &[u8] {  in data()
98         // `bindings::firmware` guarantees, if successfully requested, that  in data()
99         // `bindings::firmware::data` has a size of `bindings::firmware::size` bytes.  in data()
104 impl Drop for Firmware {  implementation
111 // SAFETY: `Firmware` only holds a pointer to a C `struct firmware`, which is safe to be used from
113 unsafe impl Send for Firmware {}  implementation
115 // SAFETY: `Firmware` only holds a pointer to a C `struct firmware`, references to which are safe to
117 unsafe impl Sync for Firmware {}  implementation