disable GPS when USB is plugged in

src/main.rs

@@ -32,7 +32,7 @@ mod app {
         packet::Packet,
         whisker::{Gps, Route},
     };
-    use stm32f4xx_hal as hal;
+    use stm32f4xx_hal::{self as hal};
     use systick_monotonic::{ExtU64, Systick};
     use usb_device::prelude::*;
 
@@ -65,6 +65,7 @@ mod app {
         gps_serial: Serial<USART2>,
         flash: LockedFlash,
         buf: &'static mut [u8; MAX_PACKET_LEN],
+        gps_enable: gpio::Pin<'C', 8, gpio::Output<gpio::OpenDrain>>,
     }
 
     #[shared]
@@ -226,6 +227,7 @@ mod app {
                 gps_serial,
                 flash,
                 buf,
+                gps_enable,
             },
             init::Monotonics(Systick::new(ctx.core.SYST, H_CLK)),
         )
@@ -316,7 +318,7 @@ mod app {
         }
     }
 
-    #[task(priority = 2, local = [green, usb_detect], shared = [red, status])]
+    #[task(priority = 2, local = [green, usb_detect, gps_enable], shared = [red, status])]
     fn led_handler(mut ctx: led_handler::Context) {
         led_handler::spawn_after(LED_BLINK_RATE.millis()).unwrap();
 
@@ -327,6 +329,7 @@ mod app {
             status.lock(|s| *s = Status::Programming(false));
 
             ctx.shared.red.lock(|red| red.set_low());
+            ctx.local.gps_enable.set_high();
         }
 
         status.lock(|s| match s {