Started a new example for 1.54 in

examples/embedded_linux_epd4in2/src/main.rs

@@ -61,10 +61,11 @@ impl<'a> InputPin for HackInputPin<'a> {
 fn main() {
 
     // Configure SPI
+    // Settings are taken from 
     let mut spi = Spidev::open("/dev/spidev0.0").expect("spidev directory");
     let options = SpidevOptions::new()
         .bits_per_word(8)
-        .max_speed_hz(1_000_000)
+        .max_speed_hz(4_000_000)
         .mode(spidev::SPI_MODE_0)
         .build();
     spi.configure(&options).expect("spi configuration");