refactor

src/backlight.rs

@@ -1,23 +1,39 @@
 use esp_hal::gpio::interconnect::PeripheralOutput;
 use esp_hal::gpio::DriveMode;
 use esp_hal::ledc::channel::{self, Channel, ChannelIFace};
-use esp_hal::ledc::timer::TimerIFace;
+use esp_hal::ledc::timer::{self, Timer, TimerIFace};
-use esp_hal::ledc::LowSpeed;
+use esp_hal::ledc::{LSGlobalClkSource, Ledc, LowSpeed};
+use esp_hal::peripherals::LEDC;
+use esp_hal::time::Rate;
+
+/// PWM frequency for the backlight (Hz).
+const BACKLIGHT_FREQ: Rate = Rate::from_khz(5);
 
 /// Maximum duty cycle percentage. The board documentation warns against
 /// running the display above 50% brightness, so `level = 1.0` maps to this.
 const MAX_DUTY_PCT: u8 = 50;
 
-#[derive(Debug)]
+/// Create and configure the LEDC timer used by the backlight.
-pub enum Error {
+///
-    Channel(channel::Error),
+/// Returns the `Ledc` and `Timer` so the caller can build a [`LcdBacklight`]
+/// that borrows the timer.
+pub fn setup_timer(
+    ledc: LEDC<'static>,
+) -> Result<(Ledc<'static>, Timer<'static, LowSpeed>), timer::Error> {
+    let mut ledc = Ledc::new(ledc);
+    ledc.set_global_slow_clock(LSGlobalClkSource::APBClk);
+
+    let mut timer = ledc.timer::<LowSpeed>(timer::Number::Timer0);
+    timer.configure(timer::config::Config {
+        duty: timer::config::Duty::Duty8Bit,
+        clock_source: timer::LSClockSource::APBClk,
+        frequency: BACKLIGHT_FREQ,
+    })?;
+
+    Ok((ledc, timer))
 }
 
-impl From<channel::Error> for Error {
+pub type Error = channel::Error;
-    fn from(e: channel::Error) -> Self {
-        Error::Channel(e)
-    }
-}
 
 /// Backlight PWM driver. The channel holds a reference to the caller-owned
 /// timer, so this type's lifetime is bounded by the timer's lifetime.
@@ -45,6 +61,6 @@ impl<'a> LcdBacklight<'a> {
     /// documentation recommends.
     pub fn set_level(&mut self, level: f32) -> Result<(), Error> {
         let duty_pct = ((level.clamp(0.0, 1.0) * MAX_DUTY_PCT as f32) + 0.5) as u8;
-        self.channel.set_duty(duty_pct).map_err(Error::Channel)
+        self.channel.set_duty(duty_pct)
     }
 }

src/led.rs

@@ -23,20 +23,7 @@ impl RgbLed {
         })
     }
 
-    pub fn set_color(
-        &mut self,
-        r: u8,
-        g: u8,
-        b: u8,
-    ) -> Result<(), esp_hal_smartled::AdapterError> {
-        self.led.write([RGB8 { r, g, b }])
-    }
-
     pub fn set_rgb(&mut self, rgb: RGB8) -> Result<(), esp_hal_smartled::AdapterError> {
         self.led.write([rgb])
     }
-
-    pub fn off(&mut self) -> Result<(), esp_hal_smartled::AdapterError> {
-        self.set_color(0, 0, 0)
-    }
 }

src/main.rs

@@ -6,8 +6,6 @@ mod led;
 
 use esp_backtrace as _;
 use esp_bootloader_esp_idf::esp_app_desc;
-use esp_hal::ledc::timer::{self, TimerIFace};
-use esp_hal::ledc::{LSGlobalClkSource, Ledc, LowSpeed};
 use esp_hal::{init, rmt::Rmt, time::Rate, Config};
 use esp_println::println;
 use smart_leds::hsv::{hsv2rgb, Hsv};
@@ -24,16 +22,8 @@ fn main() -> ! {
         led::RgbLed::new(rmt.channel0, peripherals.GPIO8).expect("Failed to init RGB LED")
     };
 
-    let mut ledc = Ledc::new(peripherals.LEDC);
+    let (_ledc, timer) =
-    ledc.set_global_slow_clock(LSGlobalClkSource::APBClk);
+        backlight::setup_timer(peripherals.LEDC).expect("Failed to init backlight timer");
-    let mut timer = ledc.timer::<LowSpeed>(timer::Number::Timer0);
-    timer
-        .configure(timer::config::Config {
-            duty: timer::config::Duty::Duty8Bit,
-            clock_source: timer::LSClockSource::APBClk,
-            frequency: Rate::from_khz(5),
-        })
-        .expect("Failed to configure backlight timer");
     let mut backlight =
         backlight::LcdBacklight::new(&timer, peripherals.GPIO22).expect("Failed to init backlight");