From ed69a7a5eaaf7cd54a156376f833886e7dfa47a9 Mon Sep 17 00:00:00 2001
From: Andreas Neuhaus <git@zargony.com>
Date: Sun, 1 Sep 2024 01:32:07 +0200
Subject: [PATCH] Refactor pn532 process function with timeout

---
 firmware/src/nfc.rs   |  8 +-------
 firmware/src/pn532.rs | 16 +++++++++++++++-
 2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/firmware/src/nfc.rs b/firmware/src/nfc.rs
index 38b50b5..7e175a3 100644
--- a/firmware/src/nfc.rs
+++ b/firmware/src/nfc.rs
@@ -9,9 +9,6 @@ use embedded_hal_async::i2c::I2c;
 use log::{debug, info, warn};
 use pn532::{Error as Pn532Error, I2CInterfaceWithIrq, Pn532, Request, SAMMode};
 
-/// NFC reader default command timeout
-const COMMAND_TIMEOUT: Duration = Duration::from_millis(50);
-
 /// NFC reader read loop timeout
 const READ_TIMEOUT: Duration = Duration::from_millis(100);
 
@@ -66,7 +63,6 @@ impl<I2C: I2c, IRQ: Wait<Error = Infallible>> Nfc<I2C, IRQ> {
                 // SAMConfiguration request (PN532 §7.2.10)
                 &Request::sam_configuration(SAMMode::Normal, true),
                 0,
-                COMMAND_TIMEOUT,
             )
             .await?;
 
@@ -76,7 +72,6 @@ impl<I2C: I2c, IRQ: Wait<Error = Infallible>> Nfc<I2C, IRQ> {
                 // GetFirmwareVersion request (PN532 §7.2.2)
                 &Request::GET_FIRMWARE_VERSION,
                 4,
-                COMMAND_TIMEOUT,
             )
             .await?;
         // GetFirmwareVersion response (PN532 §7.2.2)
@@ -108,7 +103,7 @@ impl<I2C: I2c, IRQ: Wait<Error = Infallible>> Nfc<I2C, IRQ> {
             // Detect any ISO/IEC14443 Type A target in passive mode
             let list_response = match self
                 .driver
-                .process(
+                .process_timeout(
                     // InListPassiveTarget request (PN532 §7.3.5)
                     &Request::INLIST_ONE_ISO_A_TARGET,
                     pn532::BUFFER_SIZE - 9, // max response length
@@ -167,7 +162,6 @@ impl<I2C: I2c, IRQ: Wait<Error = Infallible>> Nfc<I2C, IRQ> {
                     // InRelease request (PN532 §7.3.11)
                     &Request::RELEASE_TAG_1,
                     1,
-                    COMMAND_TIMEOUT,
                 )
                 .await
             {
diff --git a/firmware/src/pn532.rs b/firmware/src/pn532.rs
index 3ec6f2d..d3a95a7 100644
--- a/firmware/src/pn532.rs
+++ b/firmware/src/pn532.rs
@@ -15,6 +15,9 @@ pub const BUFFER_SIZE: usize = 32;
 /// Command ACK timeout
 const ACK_TIMEOUT: Duration = Duration::from_millis(50);
 
+/// Command response timeout
+const RESPONSE_TIMEOUT: Duration = Duration::from_millis(50);
+
 const PREAMBLE: [u8; 3] = [0x00, 0x00, 0xFF];
 const POSTAMBLE: u8 = 0x00;
 const ACK: [u8; 6] = [0x00, 0x00, 0xFF, 0x00, 0xFF, 0x00];
@@ -163,11 +166,22 @@ impl<I: Interface, const N: usize> Pn532<I, N> {
     }
 
     /// Send PN532 request and wait for ack and response.
-    /// Like `pn532::Pn532::process`, but fully asynchronous and with timeout
+    /// Like `pn532::Pn532::process`, but fully asynchronous
     pub async fn process<'a>(
         &mut self,
         request: impl Into<BorrowedRequest<'a>>,
         response_len: usize,
+    ) -> Result<&[u8], Error<I::Error>> {
+        self.process_timeout(request, response_len, RESPONSE_TIMEOUT)
+            .await
+    }
+
+    /// Send PN532 request and wait for ack and response.
+    /// Like `pn532::Pn532::process`, but fully asynchronous and with timeout
+    pub async fn process_timeout<'a>(
+        &mut self,
+        request: impl Into<BorrowedRequest<'a>>,
+        response_len: usize,
         timeout: Duration,
     ) -> Result<&[u8], Error<I::Error>> {
         let request = request.into();