From 6d4a49bca86415b88f282d084cfa4045c171e63a Mon Sep 17 00:00:00 2001
From: Daniel Bevenius <daniel.bevenius@gmail.com>
Date: Wed, 11 May 2022 16:23:31 +0200
Subject: [PATCH] Implement Output::is_set_low for embassy-rp

This commit implements a suggestion for the method is_set_low which is
currently a 'todo', by reading last value written to GPIO_OUT.
---
 embassy-rp/src/gpio.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/embassy-rp/src/gpio.rs b/embassy-rp/src/gpio.rs
index 59875903..9cdba8bf 100644
--- a/embassy-rp/src/gpio.rs
+++ b/embassy-rp/src/gpio.rs
@@ -127,8 +127,8 @@ impl<'d, T: Pin> Output<'d, T> {
 
     /// Is the output pin set as low?
     pub fn is_set_low(&self) -> bool {
-        // todo
-        true
+        // Reading from SIO: GPIO_OUT gives the last value written.
+        unsafe { self.pin.sio_out().value().read() == 0 }
     }
 }