Add AsRef implem to Api

coldcard/src/lib.rs

@@ -106,6 +106,12 @@ impl Api {
     }
 }
 
+impl AsRef<hidapi::HidApi> for Api {
+    fn as_ref(&self) -> &hidapi::HidApi {
+        &self.0
+    }
+}
+
 /// Specifies various options that a Coldcard can be opened with.
 #[derive(Debug)]
 pub struct Options {
@@ -181,11 +187,13 @@ impl Coldcard {
     /// Coldcard devices. Returns an optional `XpubInfo` in case the device is
     /// already initialized with a secret.
     pub fn open(
-        api: &Api,
+        api: impl AsRef<hidapi::HidApi>,
         sn: impl AsRef<str>,
         opts: Option<Options>,
     ) -> Result<(Self, Option<XpubInfo>), Error> {
-        let mut cc = api.0.open_serial(COINKITE_VID, CKCC_PID, sn.as_ref())?;
+        let mut cc = api
+            .as_ref()
+            .open_serial(COINKITE_VID, CKCC_PID, sn.as_ref())?;
 
         #[cfg(feature = "log")]
         log::info!("opened SN {} with opts: {:?}", sn.as_ref(), opts);