Struct OptionalClk

pub struct OptionalClk(/* private fields */);

A reference-counted optional clock.

A lightweight wrapper around an optional Clk. An OptionalClk represents a Clk that a driver can function without but may improve performance or enable additional features when available.

Invariants

An OptionalClk instance encapsulates a Clk with either a valid struct clk or NULL pointer.

Instances of this type are reference-counted. Calling OptionalClk::get ensures that the allocation remains valid for the lifetime of the OptionalClk.

Examples

The following example demonstrates how to obtain and configure an optional clock for a device. The code functions correctly whether or not the clock is available.

use kernel::c_str;
use kernel::clk::{OptionalClk, Hertz};
use kernel::device::Device;
use kernel::error::Result;

fn configure_clk(dev: &Device) -> Result {
    let clk = OptionalClk::get(dev, Some(c_str!("apb_clk")))?;

    clk.prepare_enable()?;

    let expected_rate = Hertz::from_ghz(1);

    if clk.rate() != expected_rate {
        clk.set_rate(expected_rate)?;
    }

    clk.disable_unprepare();
    Ok(())
}

Implementations

impl OptionalClk

pub fn get(dev: &Device, name: Option<&CStr>) -> Result<Self>

Gets OptionalClk corresponding to a Device and a connection id.

Equivalent to the kernel’s clk_get_optional API.

Methods from Deref<Target = Clk>

pub fn as_raw(&self) -> *mut clk

Obtain the raw [struct clk] pointer.

pub fn enable(&self) -> Result

Enable the clock.

Equivalent to the kernel’s clk_enable API.

pub fn disable(&self)

Disable the clock.

Equivalent to the kernel’s clk_disable API.

pub fn prepare(&self) -> Result

Prepare the clock.

Equivalent to the kernel’s clk_prepare API.

pub fn unprepare(&self)

Unprepare the clock.

Equivalent to the kernel’s clk_unprepare API.

pub fn prepare_enable(&self) -> Result

Prepare and enable the clock.

Equivalent to calling Clk::prepare followed by Clk::enable.

pub fn disable_unprepare(&self)

Disable and unprepare the clock.

Equivalent to calling Clk::disable followed by Clk::unprepare.

pub fn rate(&self) -> Hertz

Get clock’s rate.

Equivalent to the kernel’s clk_get_rate API.

pub fn set_rate(&self, rate: Hertz) -> Result

Set clock’s rate.

Equivalent to the kernel’s clk_set_rate API.

Trait Implementations

impl Deref for OptionalClk

type Target = Clk

The resulting type after dereferencing.

fn deref(&self) -> &Clk

Dereferences the value.