From 32850bba79cbf5fcb06f8068cfd46919020b19be Mon Sep 17 00:00:00 2001
From: Jacob Rosenthal <jacobrosenthal@gmail.com>
Date: Sat, 23 Oct 2021 15:53:31 -0700
Subject: [PATCH] nrf: saadc dummy pin for vdd sampling

---
 embassy-nrf/src/saadc.rs | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/embassy-nrf/src/saadc.rs b/embassy-nrf/src/saadc.rs
index 215f968a7..efcdfb2b1 100644
--- a/embassy-nrf/src/saadc.rs
+++ b/embassy-nrf/src/saadc.rs
@@ -78,6 +78,29 @@ pub struct ChannelConfig<'d> {
     phantom: PhantomData<&'d ()>,
 }
 
+/// A dummy `Input` pin implementation for SAADC peripheral sampling from the
+/// internal voltage.
+pub struct VddInput;
+
+unsafe impl Unborrow for VddInput {
+    type Target = VddInput;
+    unsafe fn unborrow(self) -> Self::Target {
+        self
+    }
+}
+
+impl sealed::Input for VddInput {
+    #[cfg(not(feature = "nrf9160"))]
+    fn channel(&self) -> InputChannel {
+        InputChannel::VDD
+    }
+    #[cfg(feature = "nrf9160")]
+    fn channel(&self) -> InputChannel {
+        InputChannel::VDDGPIO
+    }
+}
+impl Input for VddInput {}
+
 impl<'d> ChannelConfig<'d> {
     /// Default configuration for single ended channel sampling.
     pub fn single_ended(input: impl Unborrow<Target = impl Input> + 'd) -> Self {